WorldWideScience

Sample records for apportionment

  1. Source apportionment of indoor air pollution

    Science.gov (United States)

    Sexton, Ken; Hayward, Steven B.

    An understanding of the relative contributions from important pollutant sources to human exposures is necessary for the design and implementation of effective control strategies. In the past, societal efforts to control air pollution have focused almost exclusively on the outdoor (ambient) environment. As a result, substantial amounts of time and money have been spent to limit airborne discharges from mobile and stationary sources. Yet it is now recognized that exposures to elevated pollutant concentrations often occur as a result of indoor, rather than outdoor, emissions. While the major indoor sources have been identified, their relative impacts on indoor air quality have not been well defined. Application of existing source apportionment models to nonindustrial indoor environments is only just beginning. It is possible that these models might be used to distinguish between indoor and outdoor emissions, as well as to distinguish among indoor sources themselves. However, before the feasibility and suitability of source-apportionment methods for indoor applications can be assessed adequately, it is necessary to take account of model assumptions and associated data requirements. This paper examines the issue of indoor source apportionment and reviews the need for emission characterization studies to support such source-apportionment efforts.

  2. 26 CFR 1.904-6 - Allocation and apportionment of taxes.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 9 2010-04-01 2010-04-01 false Allocation and apportionment of taxes. 1.904-6... apportionment of taxes. (a) Allocation and apportionment of taxes to a separate category or categories of income... for the direct allocation or apportionment of expenses, losses, or other deductions to a...

  3. 42 CFR 413.50 - Apportionment of allowable costs.

    Science.gov (United States)

    2010-10-01

    ... MEDICARE PROGRAM PRINCIPLES OF REASONABLE COST REIMBURSEMENT; PAYMENT FOR END-STAGE RENAL DISEASE SERVICES; OPTIONAL PROSPECTIVELY DETERMINED PAYMENT RATES FOR SKILLED NURSING FACILITIES Apportionment § 413.50 Apportionment of allowable costs. (a) Consistent with prevailing practice in which third-party organizations...

  4. 77 FR 2225 - Allocation and Apportionment of Interest Expense

    Science.gov (United States)

    2012-01-17

    .... Affiliated Groups The interest expense of each member of an affiliated group is allocated and apportioned as... income that is taken into account for purposes of applying the affiliated group interest apportionment... be treated as a member of an affiliated group for interest allocation and apportionment purposes...

  5. Divisor-Based Biproportional Apportionment in Electoral Systems

    DEFF Research Database (Denmark)

    Maier, Sebastian; Zachariassen, Petur; Zachariasen, Martin

    2010-01-01

    in an electoral system context. By performing experiments on real-life benchmark instances (election data with multimember districts), we evaluate the general quality of divisor-based apportionments with respect to, e.g., deviation from quota, reversal orderings, and occurrences of ties. For example......- and column-sum requirements are fulfilled. In a divisor-based method for biproportional apportionment, the problem is solved by computing appropriate row and column divisors, and by rounding the quotients. We present a comprehensive experimental evaluation of divisor-based biproportional apportionment...

  6. 26 CFR 1.863-3 - Allocation and apportionment of income from certain sales of inventory.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 9 2010-04-01 2010-04-01 false Allocation and apportionment of income from... within Or Without the United States § 1.863-3 Allocation and apportionment of income from certain sales...) Allocation or apportionment for Possession Production Sales—(i) Methods for determining the source of...

  7. 42 CFR 417.566 - Other methods of allocation and apportionment.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Other methods of allocation and apportionment. 417..., AND HEALTH CARE PREPAYMENT PLANS Medicare Payment: Cost Basis § 417.566 Other methods of allocation and apportionment. (a) Justification. A method of apportionment or allocation of costs, other than...

  8. Source apportionment in oil spill remediation.

    Science.gov (United States)

    Muñoz, Jorge; Mudge, Stephen M; Loyola-Sepulveda, Rodrigo; Muñoz, Gonzalo; Bravo-Linares, Claudio

    2012-05-01

    A pipe rupture during unloading led to a spillage of 350-700 tonnes of Caño Limon, a light sweet crude oil, into San Vicente Bay in 2007. Initial clean-up methods removed the majority of the oil from the sandy beaches although some oil remained on the rocky shores. It was necessary for the responsible party to clean the spilled oil even though at this location there were already crude oil hydrocarbons from previous industrial activity. A biosolvent based on vegetable oil derivatives was used to solubilise the remaining oil and a statistical approach to source apportionment was used to determine the efficacy of the cleaning. Sediment and contaminated rock samples were taken prior to cleaning and again at the same locations two days after application of the biosolvent. The oil was extracted using a modified USEPA Method 3550B. The alkanes were quantified together with oil biomarkers on a GC-MS. The contribution that Caño Limon made to the total oil hydrocarbons was calculated from a Partial Least Squares (PLS) analysis using Caño Limon crude oil as the source. By the time the biosolvent was applied, there had already been some attenuation of the oil with all alkanes

  9. Source apportionment in oil spill remediation.

    Science.gov (United States)

    Muñoz, Jorge; Mudge, Stephen M; Loyola-Sepulveda, Rodrigo; Muñoz, Gonzalo; Bravo-Linares, Claudio

    2012-05-01

    A pipe rupture during unloading led to a spillage of 350-700 tonnes of Caño Limon, a light sweet crude oil, into San Vicente Bay in 2007. Initial clean-up methods removed the majority of the oil from the sandy beaches although some oil remained on the rocky shores. It was necessary for the responsible party to clean the spilled oil even though at this location there were already crude oil hydrocarbons from previous industrial activity. A biosolvent based on vegetable oil derivatives was used to solubilise the remaining oil and a statistical approach to source apportionment was used to determine the efficacy of the cleaning. Sediment and contaminated rock samples were taken prior to cleaning and again at the same locations two days after application of the biosolvent. The oil was extracted using a modified USEPA Method 3550B. The alkanes were quantified together with oil biomarkers on a GC-MS. The contribution that Caño Limon made to the total oil hydrocarbons was calculated from a Partial Least Squares (PLS) analysis using Caño Limon crude oil as the source. By the time the biosolvent was applied, there had already been some attenuation of the oil with all alkanes oil in this case and the contribution that Caño Limon made to the total oil ranged from 0% to 74%. The total hydrocarbon concentrations were lower after cleaning indicating an efficacy of 90% although the reduction in Caño Limon oil was smaller. This was sufficient to make further remediation unnecessary.

  10. 33 CFR 277.8 - Procedures for apportionment of costs.

    Science.gov (United States)

    2010-07-01

    ... and insulation in the machinery house. (xi) Operator's house furnishings, air-conditioners, water..., DEPARTMENT OF DEFENSE WATER RESOURCES POLICIES AND AUTHORITIES: NAVIGATION POLICY: COST APPORTIONMENT OF... present worth computation is that established by the Water Resources Council, current at the time of...

  11. Tax competition with formula apportionment: the interaction between tax base and sharing mechanism

    OpenAIRE

    Kolmar, Martin; Wagener, Andreas

    2007-01-01

    The EU Commission is advocating a common consolidated tax base for the corporate income tax, accompanied by a revenue sharing mechanism based on formula apportionment. We analyse tax competition in such a regime, focussing on the interaction between the definition of the tax base and the apportionment method. Tax competition leads to suboptimally low tax rates if and only if the investment elasticity of the tax base is lower than the investment elasticity of the apportionment factor. For any ...

  12. Risk Apportionment for Railway System using Constraint Programming

    OpenAIRE

    RAFRAFI,M; El-Koursi, Em

    2008-01-01

    The apportionment of railway safety targets is a key issue to develop a common safety management in the European railway system. In this paper, we develop a generic approach based on the functional railway architecture, to analyse the safety of railway systems for a unified European network and to comply with the Common Safety Targets (CSTs) required by the European railway safety directive. We suggest to use constraint programming with the functional railway architecture, developed by the AE...

  13. Source Apportionment of Fine Particles in Xinzhen, Beijing

    Institute of Scientific and Technical Information of China (English)

    JIN; Xiang-chun; ZHANG; Gui-ying; XIAO; Cai-jin; WANG; Ping-sheng; WANG; Xing-hua; HUA; Long; YAO; Yong-gang; YUAN; Guo-jun; NI; Bang-fa

    2013-01-01

    As the capital city of China,Beijing often suffers from hazy weather recently.In order to improve air quality,it is of great importance to perform source apportionment and source trajectory.A total of 140airborne particulate matter samples were collected at Xinzhen from May,2007 to July,2013 and their chemical compositions were analyzed by Particle Induced X-ray Emission(PIXE)and Energy Disperse-X

  14. 7 CFR 1412.49 - Apportionment of long and medium grain rice.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Apportionment of long and medium grain rice. 1412.49... and Peanuts 2008 through 2012 § 1412.49 Apportionment of long and medium grain rice. (a) Rice base... rice base acres in paragraph (a) of this section into two categories: (i) Long grain rice, and...

  15. 42 CFR 417.564 - Apportionment and allocation of administrative and general costs.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Apportionment and allocation of administrative and... Apportionment and allocation of administrative and general costs. (a) Costs not directly associated with... administrative and general costs that are not included in paragraph (a) of this section. (2) The allocation...

  16. 26 CFR 1.863-2 - Allocation and apportionment of taxable income.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 9 2010-04-01 2010-04-01 false Allocation and apportionment of taxable income... States § 1.863-2 Allocation and apportionment of taxable income. (a) Determination of taxable income... (as contained in 26 CFR part 1 revised as of April 1, 1996)....

  17. Source apportionment of airborne particulates through receptor modeling: Indian scenario

    Science.gov (United States)

    Banerjee, Tirthankar; Murari, Vishnu; Kumar, Manish; Raju, M. P.

    2015-10-01

    Airborne particulate chemistry mostly governed by associated sources and apportionment of specific sources is extremely essential to delineate explicit control strategies. The present submission initially deals with the publications (1980s-2010s) of Indian origin which report regional heterogeneities of particulate concentrations with reference to associated species. Such meta-analyses clearly indicate the presence of reservoir of both primary and secondary aerosols in different geographical regions. Further, identification of specific signatory molecules for individual source category was also evaluated in terms of their scientific merit and repeatability. Source signatures mostly resemble international profile while, in selected cases lack appropriateness. In India, source apportionment (SA) of airborne particulates was initiated way back in 1985 through factor analysis, however, principal component analysis (PCA) shares a major proportion of applications (34%) followed by enrichment factor (EF, 27%), chemical mass balance (CMB, 15%) and positive matrix factorization (PMF, 9%). Mainstream SA analyses identify earth crust and road dust resuspensions (traced by Al, Ca, Fe, Na and Mg) as a principal source (6-73%) followed by vehicular emissions (traced by Fe, Cu, Pb, Cr, Ni, Mn, Ba and Zn; 5-65%), industrial emissions (traced by Co, Cr, Zn, V, Ni, Mn, Cd; 0-60%), fuel combustion (traced by K, NH4+, SO4-, As, Te, S, Mn; 4-42%), marine aerosols (traced by Na, Mg, K; 0-15%) and biomass/refuse burning (traced by Cd, V, K, Cr, As, TC, Na, K, NH4+, NO3-, OC; 1-42%). In most of the cases, temporal variations of individual source contribution for a specific geographic region exhibit radical heterogeneity possibly due to unscientific orientation of individual tracers for specific source and well exaggerated by methodological weakness, inappropriate sample size, implications of secondary aerosols and inadequate emission inventories. Conclusively, a number of challenging

  18. Indoor source apportionment in urban communities near industrial sites

    Science.gov (United States)

    Tunno, Brett J.; Dalton, Rebecca; Cambal, Leah; Holguin, Fernando; Lioy, Paul; Clougherty, Jane E.

    2016-08-01

    Because fine particulate matter (PM2.5) differs in chemical composition, source apportionment is frequently used for identification of relative contributions of multiple sources to outdoor concentrations. Indoor air pollution and source apportionment is often overlooked, though people in northern climates may spend up to 90% of their time inside. We selected 21 homes for a 1-week indoor sampling session during summer (July to September 2011), repeated in winter (January to March 2012). Elemental analysis was performed using inductively-coupled plasma mass spectrometry (ICP-MS), and factor analysis was used to determine constituent grouping. Multivariate modeling was run on factor scores to corroborate interpretations of source factors based on a literature review. For each season, a 5-factor solution explained 86-88% of variability in constituent concentrations. Indoor sources (i.e. cooking, smoking) explained greater variability than did outdoor sources in these industrial communities. A smoking factor was identified in each season, predicted by number of cigarettes smoked. Cooking factors were also identified in each season, explained by frequency of stove cooking and stovetop frying. Significant contributions from outdoor sources including coal and motor vehicles were also identified. Higher coal and secondary-related elemental concentrations were detected during summer than winter. Our findings suggest that source contributions to indoor concentrations can be identified and should be examined in relation to health effects.

  19. Enterococcus and Escherichia coli fecal source apportionment with microbial source tracking genetic markers - is it feasible?

    Science.gov (United States)

    Fecal pollution is measured in surface waters using culture-based measurements of enterococci and Escherichia coli bacteria. Source apportionment of these two fecal indicator bacteria is an urgent need for prioritizing remediation efforts and quantifying health risks associated...

  20. Critical review of black carbon and elemental carbon source apportionment in Europe and the United States

    Science.gov (United States)

    Briggs, Nicole L.; Long, Christopher M.

    2016-11-01

    An increasing number of air pollution source apportionment studies in Europe and the United States have focused on the black carbon (BC) fraction of ambient particulate matter (PM) given its linkage with adverse public health and climate impacts. We conducted a critical review of European and US BC source apportionment studies published since 2003. Since elemental carbon (EC) has been used as a surrogate measure of BC, we also considered source apportionment studies of EC measurements. This review extends the knowledge presented in previous ambient PM source apportionment reviews because we focus on BC and EC and critically examine the differences between source apportionment results for different methods and source categories. We identified about 50 BC and EC source apportionment studies that have been conducted in either Europe or the US since 2003, finding a striking difference in the commonly used source apportionment methods between the two regions and variations in the assigned source categories. Using three dominant methodologies (radiocarbon, aethalometer, and macro-tracer methods) that only allow for BC to be broadly apportioned into either fossil fuel combustion or biomass burning source categories, European studies generally support fossil fuel combustion as the dominant ambient BC source, but also show significant biomass burning contributions, in particular in wintertime at non-urban locations. Among US studies where prevailing methods such as chemical mass balance (CMB) and positive matrix factorization (PMF) models have allowed for estimation of more refined source contributions, there are fewer findings showing the significance of biomass burning and variable findings on the relative proportion of BC attributed to diesel versus gasoline emissions. Overall, the available BC source apportionment studies provide useful information demonstrating the significance of both fossil fuel combustion and biomass burning BC emission sources in Europe and the US

  1. Block Tensor Decomposition for Source Apportionment of Air Pollution

    CERN Document Server

    Hopke, Philip K; Li, Na; Navasca, Carmeliza

    2011-01-01

    The ambient particulate chemical composition data with three particle diameter sizes (2.5mmapportionment analysis calls for a novel multiway factor analysis. We apply the regularized block tensor decomposition to the collected air sample data. In particular, we use the Block Term Decomposition (BTD) in rank-(L;L;1) form to identify nine pollution sources (Fe+Zn, Sulfur with Dust, Road Dust, two types of Metal Works, Road Salt, Local Sulfate, and Homogeneous and Cloud Sulfate).

  2. Source apportionment of carbonaceous aerosol in southern Sweden

    Directory of Open Access Journals (Sweden)

    J. Genberg

    2011-05-01

    Full Text Available A one-year study was performed at the Vavihill background station in southern Sweden to estimate the anthropogenic contribution to the carbonaceous aerosol. Weekly samples of the particulate matter PM10 were collected on quartz filters, and the amounts of organic carbon, elemental carbon, radiocarbon (14C and levoglucosan were measured. This approach enabled source apportionment of the total carbon in the PM10 fraction using the concentration ratios of the sources. The sources considered in this study were emissions from the combustion of fossil fuels and biomass, as well as biogenic sources. During the summer, the carbonaceous aerosol mass was dominated by compounds of biogenic origin (82 %, which are associated with biogenic primary and secondary organic aerosols. During the winter months, biomass combustion (38 % and fossil fuel combustion (33 % were the main contributors to the carbonaceous aerosol. Elemental carbon concentrations in winter were about twice as large as during summer, and can be attributed to biomass combustion, probably from domestic wood burning. The contribution of fossil fuels to elemental carbon was stable throughout the year, although the fossil contribution to organic carbon increased during the winter. Thus, the organic aerosol originated mainly from natural sources during the summer and from anthropogenic sources during the winter. The result of this source apportionment was compared with results from the EMEP model. The model and measurements were generally consistent for total atmospheric organic carbon, however, the contribution of the sources varied substantially. E.g. the biomass burning contributions of OC were underestimated by the model by a factor of 8.2 compared to the measurements.

  3. Aerosol composition and source apportionment in Santiago de Chile

    Energy Technology Data Exchange (ETDEWEB)

    Artaxo, Paulo E-mail: artaxo@if.usp.br; Oyola, Pedro; Martinez, Roberto

    1999-04-02

    Santiago de Chile, Sao Paulo and Mexico City are Latin American urban areas that suffer from heavy air pollution. In order to study air pollution in Santiago area, an aerosol source apportionment study was designed to measure ambient aerosol composition and size distribution for two downtown sampling sites in Santiago. The aerosol monitoring stations were operated in Gotuzo and Las Condes during July and August 1996. The study employed stacked filter units (SFU) for aerosol sampling, collecting fine mode aerosol (dp<2 {mu}m) and coarse mode aerosol (2apportionment was performed using Absolute Principal Factor Analysis (APFA). Very high aerosol concentrations were observed (up to 400 {mu}g/m{sup 3} PM{sub 10}). The main aerosol particle sources in Santiago are resuspended soil dust and traffic emissions. Coarse particles account for 63% of PM{sub 10} aerosol in Gotuzo and 53% in Las Condes. A major part of this component is resuspended soil dust. In the fine fraction, resuspended soil dust accounts for 15% of fine mass, and the aerosols associated with transportation activities account for a high 64% of the fine particle mass. Sulfate particle is an important component of the aerosol in Santiago, mainly originating from gas-to-particle conversion from SO{sub 2}. In the Gotuzo site, sulfates are the highest aerosol component, accounting for 64.5% of fine mass. Direct traffic emissions are generally mixed with resuspended soil dust. It is difficult to separate the two components, because the soil dust in downtown Santiago is contaminated with Pb, Br, Cl, and other heavy metals that are also tracers for traffic emissions. Residual oil combustion is observed

  4. Nitrate source apportionment in a subtropical watershed using Bayesian model

    International Nuclear Information System (INIS)

    Nitrate (NO3−) pollution in aquatic system is a worldwide problem. The temporal distribution pattern and sources of nitrate are of great concern for water quality. The nitrogen (N) cycling processes in a subtropical watershed located in Changxing County, Zhejiang Province, China were greatly influenced by the temporal variations of precipitation and temperature during the study period (September 2011 to July 2012). The highest NO3− concentration in water was in May (wet season, mean ± SD = 17.45 ± 9.50 mg L−1) and the lowest concentration occurred in December (dry season, mean ± SD = 10.54 ± 6.28 mg L−1). Nevertheless, no water sample in the study area exceeds the WHO drinking water limit of 50 mg L−1 NO3−. Four sources of NO3− (atmospheric deposition, AD; soil N, SN; synthetic fertilizer, SF; manure and sewage, M and S) were identified using both hydrochemical characteristics [Cl−, NO3−, HCO3−, SO42−, Ca2+, K+, Mg2+, Na+, dissolved oxygen (DO)] and dual isotope approach (δ15N–NO3− and δ18O–NO3−). Both chemical and isotopic characteristics indicated that denitrification was not the main N cycling process in the study area. Using a Bayesian model (stable isotope analysis in R, SIAR), the contribution of each source was apportioned. Source apportionment results showed that source contributions differed significantly between the dry and wet season, AD and M and S contributed more in December than in May. In contrast, SN and SF contributed more NO3− to water in May than that in December. M and S and SF were the major contributors in December and May, respectively. Moreover, the shortcomings and uncertainties of SIAR were discussed to provide implications for future works. With the assessment of temporal variation and sources of NO3−, better agricultural management practices and sewage disposal programs can be implemented to sustain water quality in subtropical watersheds. - Highlights: • Nitrate concentration in water displayed

  5. Photochemical grid model implementation of VOC, NOx, and O3 source apportionment

    Directory of Open Access Journals (Sweden)

    R. H. F. Kwok

    2014-09-01

    Full Text Available For the purposes of developing optimal emissions control strategies, efficient approaches are needed to identify the major sources or groups of sources that contribute to elevated ozone (O3 concentrations. Source based apportionment techniques implemented in photochemical grid models track sources through the physical and chemical processes important to the formation and transport of air pollutants. Photochemical model source apportionment has been used to estimate impacts of specific sources, groups of sources (sectors, sources in specific geographic areas, and stratospheric and lateral boundary inflow on O3. The implementation and application of a source apportionment technique for O3 and its precursors, nitrogen oxides (NOx and volatile organic compounds (VOC, for the Community Multiscale Air Quality (CMAQ model are described here. The Integrated Source Apportionment Method (ISAM O3 approach is a hybrid of source apportionment and source sensitivity in that O3 production is attributed to precursor sources based on O3 formation regime (e.g., for a NOx-sensitive regime, O3 is apportioned to participating NOx emissions. This implementation is illustrated by tracking multiple emissions source sectors and lateral boundary inflow. NOx, VOC, and O3 attribution to tracked sectors in the application are consistent with spatial and temporal patterns of precursor emissions. The O3 ISAM implementation is further evaluated through comparisons of apportioned ambient concentrations and deposition amounts with those derived from brute force zero-out scenarios, with correlation coefficients ranging between 0.58 and 0.99 depending on specific combination of target species and tracked precursor emissions. Low correlation coefficients occur for chemical regimes that have strong non-linearity in O3 sensitivity, which demonstrates different functionalities between source apportionment and zero-out approaches, depending on whether sources of interest are either to

  6. Dose apportionment criteria and disposal rate limits for near surface radioactive waste disposal facilities

    International Nuclear Information System (INIS)

    The dose apportionment for near surface disposal facilities (NSDFs) in India is regulated as 0.05 mSv/y uniformly for all the sites. However, the nuclear power capacity at different sites is different and the generation of low and intermediate level waste (LILW) at these sites depends on the nuclear power capacity. Therefore, the dose apportionment for the NSDFs should be site-specific and there is a need to review the adequacy of the existing dose apportionment. In this paper, an environmental exposure assessment model is used to estimate the spatial and temporal profile of the effective dose rates to members of the public due to the disposal facility through groundwater drinking pathway. The model considers continuous disposal of radioactive waste into the facility for 50 years and leaching of the radionuclides from the waste form into the groundwater flowing in the unconfined aquifer below. Uncertainty analysis of five parameters such as the distribution coefficient, fractional release rate, groundwater velocity, longitudinal dispersivity and thickness of the aquifer is also carried out using the stochastic response surface method to derive a safety factor. The dose apportionment and discharge rate limits for the NSDFs at Trombay, Rawatbhata, Narora, and Kaiga are estimated as an example. It is concluded from the study that the dose apportionment for the NSDFs satisfy the regulation of 0.05 mSv/y for these sites. It is to be noted that the LILW from nuclear power plants (NPPs) and fuel-reprocessing plants (FRPs) under operation are only considered for this review. This study underlines the importance of site-specificity of the dose apportionment for the NSDFs and reiterates the need for its periodic review whenever changes in the inventory of LILW are expected. (author)

  7. Source Apportionment of Particulate Matter Sampled in Cape Verde

    Science.gov (United States)

    Marta Almeida, Susana; Almeida-Silva, Marina; Pio, Casimiro; Nunes, Teresa; Cardoso, João; Cerqueira, Mário; Reis, Miguel; Chaves, Paula Cristina; Taborda, Ana

    2013-04-01

    Due to its geographical position, Cape Verde is highly affected by the transport of dust from the Sahara desert. Consequently, very high concentrations of particles are registered in this archipelago, being essential to elucidate the role that Saharan dust may play in the degradation of Cape Verde air quality, human health, wellbeing, visibility, tourism and economy. The objective of this study was to identify the main sources and origins of particles sampled in Cape Verde. PM10 was sampled during 2011 and chemical characterization of particles was performed by Neutron Activation Analysis and Particle Induced X-ray Emission for elemental measurements, by Ion Chromatography for the determination of water soluble ions and by a Thermal-optical system for the measurement of carbonaceous aerosol. Source apportionment was performed by integrating Positive Matrix Factorization and Backward Trajectory Analysis. Results showed that in average 68% of the PM10 mass in Cape Verde had a natural origin, being 48% associated with the soil and 20% associated with the sea. During the transport of dust from the Sahara desert the contribution of mineral aerosol increased significantly (69% during periods affected by trajectories provided from Sahara desert versus 13% during periods affected by local sources).

  8. Receptor models for source apportionment of remote aerosols in Brazil

    International Nuclear Information System (INIS)

    The PIXE (particle induced X-ray emission), and PESA (proton elastic scattering analysis) method were used in conjunction with receptor models for source apportionment of remote aerosols in Brazil. The PIXE used in the determination of concentration for elements with Z >- 11, has a detection limit of about 1 ng/m3. The concentrations of carbon, nitrogen and oxygen in the fine fraction of Amazon Basin aerosols was measured by PESA. We sampled in Jureia (SP), Fernando de Noronha, Arembepe (BA), Firminopolis (GO), Itaberai (GO) and Amazon Basin. For collecting the airbone particles we used cascade impactors, stacked filter units, and streaker samplers. Three receptor models were used: chemical mass balance, stepwise multiple regression analysis and principal factor analysis. The elemental and gravimetric concentrations were explained by the models within the experimental errors. Three sources of aerosol were quantitatively distinguished: marine aerosol, soil dust and aerosols related to forests. The emission of aerosols by vegetation is very clear for all the sampling sites. In Amazon Basin and Jureia it is the major source, responsible for 60 to 80% of airborne concentrations. (Author)

  9. Heat Flux Apportionment to Heterogeneous Surfaces Using Flux Footprint Analysis

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Heat flux data collected from the Baiyangdian Heterogeneous Field Experiment were analyzed using the footprint method. High resolution (25 m) Landsat-5 satellite imaging was used to determine the land cover as one of four surface types: farmland, lake, wetland, or village. Data from two observation sites in September 2005 were used. One site (Wangjiazhai) was characterized by highly heterogeneous surfaces in the central area of the Baiyangdian: lake/wetland. The other site (Xiongxian) was on land with more uniform surface cover. An improved Eulerian analytical flux footprint model was used to determine "source areas" of the heat fluxes measured at towers located at each site from surrounding landscapes of mixed surface types.In relative terms results show that wetland and lake areas generally contributed most to the observed heat flux at Wangjiazhai, while farmland contributed most at Xiongxian. Given the areal distribution of surface type contributions, calculations were made to obtain the magnitudes of the heat flux from lake, wetland and farmland to the total observed flux and apportioned contributions of each surface type to the sensible and latent heat fluxes. Results show that on average the sensible heat flux from wetland and farmland were comparable over the diurnal cycle, while the latent heat flux from farmland was somewhat larger by about 30-50 W m-2 during daytime. The latent and sensible fluxes from the lake source in daytime were about 50 W m-2 and 100 W m-2 less, respectively, than from wetland and farmland. The results are judged reasonable and serve to demonstrate the potential for flux apportionment over heterogeneous surfaces.

  10. Receptor Model Source Apportionment of Nonmethane Hydrocarbons in Mexico City

    Directory of Open Access Journals (Sweden)

    V. Mugica

    2002-01-01

    Full Text Available With the purpose of estimating the source contributions of nonmethane hydrocarbons (NMHC to the atmosphere at three different sites in the Mexico City Metropolitan Area, 92 ambient air samples were measured from February 23 to March 22 of 1997. Light- and heavy-duty vehicular profiles were determined to differentiate the NMHC contribution of diesel and gasoline to the atmosphere. Food cooking source profiles were also determined for chemical mass balance receptor model application. Initial source contribution estimates were carried out to determine the adequate combination of source profiles and fitting species. Ambient samples of NMHC were apportioned to motor vehicle exhaust, gasoline vapor, handling and distribution of liquefied petroleum gas (LP gas, asphalt operations, painting operations, landfills, and food cooking. Both gasoline and diesel motor vehicle exhaust were the major NMHC contributors for all sites and times, with a percentage of up to 75%. The average motor vehicle exhaust contributions increased during the day. In contrast, LP gas contribution was higher during the morning than in the afternoon. Apportionment for the most abundant individual NMHC showed that the vehicular source is the major contributor to acetylene, ethylene, pentanes, n-hexane, toluene, and xylenes, while handling and distribution of LP gas was the major source contributor to propane and butanes. Comparison between CMB estimates of NMHC and the emission inventory showed a good agreement for vehicles, handling and distribution of LP gas, and painting operations; nevertheless, emissions from diesel exhaust and asphalt operations showed differences, and the results suggest that these emissions could be underestimated.

  11. Source Apportionment of Atmospheric Mercury Using Positive Matrix Factorization

    Science.gov (United States)

    Richards, L. M.; Perry, K. D.; Abbott, M. L.

    2008-12-01

    A growing problem in the western United States is the widespread contamination of remote lakes by the atmospheric transport and deposition of mercury. Because methylmercury is known to bioaccumulate within the food chain, even small amounts of mercury introduced into an aquatic ecosystem can result in fish that are unsuitable for human consumption. The problem is complex because many natural and anthropogenic sources of mercury exist within the western United States (e.g., coal combustion, cement production, wildfires, mining activities, and emissions from naturally enriched soils and geothermal areas). Mercury can also be transported intercontinental distances (e.g., Asian coal combustion) under appropriate meteorological conditions. Thus, any mercury source apportionment study must be able to distinguish between these disparate source types. In this study, we measured gaseous elemental mercury (GEM), reactive gaseous mercury (RGM), and particulate mercury (HgP) with a Tekran system near Salmon Falls Creek Reservoir in south-central Idaho. These measurements were made during a series of one-month-long, intensive operation periods (IOPs) in the winter, spring, and summer of 2008. In each IOP, we also made coincident size- and time-resolved aerosol elemental composition measurements using an 8-stage rotating drum impactor and synchrotron X-ray fluorescence (SXRF) analysis. The SXRF analysis provided aerosol elemental concentration measurements with 3-hour time resolution. The Positive Matrix Factorization (PMF) receptor model was applied to the high-resolution, aerosol elemental composition data from each IOP to determine the temporal variability of the contributing source types based on the calculated source profiles. A multiple linear regression (MLR) technique was then used to apportion the measured mercury concentrations to the source types identified by the PMF analysis.

  12. Source apportionment of toxic chemical pollutants at Trombay region

    International Nuclear Information System (INIS)

    the concentration data. Factor analysis, a form of receptor modeling technique was used for source apportionment of different fractions of atmospheric aerosols. This study will provide information feedback on the actual effects of anthropogenic activities on the local environment. (author)

  13. 14 CFR 1214.105 - Apportionment and/or assignment of services.

    Science.gov (United States)

    2010-01-01

    ... and/or assignment of Shuttle services may take place outside the payload. (b) Integration of... assistance in such integration will be provided as an optional service. (c) Customers intending to apportion... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Apportionment and/or assignment of...

  14. 7 CFR Appendix to Part 227 - Apportionment of Funds for Nutrition Education and Training

    Science.gov (United States)

    2010-01-01

    ... NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS NUTRITION EDUCATION AND TRAINING... Pursuant to sections 19(j) of the Child Nutrition Act of 1966, as amended (42 U.S.C. 1788), funds available... 7 Agriculture 4 2010-01-01 2010-01-01 false Apportionment of Funds for Nutrition Education...

  15. Synthesizing Scientific Progress: Outcomes from US EPA’s Carbonaceous Aerosols and Source Apportionment STAR Grants

    Science.gov (United States)

    ABSTRACTA number of studies in the past decade have transformed the way we think about atmospheric aerosols. The advances include, but are not limited to, source apportionment of organics using aerosol mass spectrometer data, the volatility basis set approach, quantifying isopre...

  16. 77 FR 1785 - FTA Fiscal Year 2012 Apportionments, Allocations, and Program Information

    Science.gov (United States)

    2012-01-11

    ... more notices apportioning funds appropriated by law. In some cases, if less than a full year of funds... announcing partial apportionment for programs funded with Fiscal Year (FY) 2012 contract authority because the current authorization of FTA's programs provides contract authority for the period October 1,...

  17. Spallation Neutron Source Availability Top-Down Apportionment Using Characteristic Factors and Expert Opinion

    International Nuclear Information System (INIS)

    Apportionment is the assignment of top-level requirements to lower tier elements of the overall facility. A method for apportioning overall facility availability requirements among systems and subsystems is presented. Characteristics that influence equipment reliability and maintainability are discussed. Experts, using engineering judgment, scored each characteristic for each system whose availability design goal is to be established. The Analytic Hierarchy Process (AHP) method is used to produce a set of weighted rankings for each characteristic for each alternative system. A mathematical model is derived which incorporates these weighting factors. The method imposes higher availability requirements on those systems in which an incremental increase in availability is easier to achieve, and lower availability requirements where greater availability is more difficult and costly. An example is given of applying this top-down apportionment methodology to the Spallation Neutron Source (SNS) facility

  18. Problems in the fingerprints based polycyclic aromatic hydrocarbons source apportionment analysis and a practical solution.

    Science.gov (United States)

    Zou, Yonghong; Wang, Lixia; Christensen, Erik R

    2015-10-01

    This work intended to explain the challenges of the fingerprints based source apportionment method for polycyclic aromatic hydrocarbons (PAH) in the aquatic environment, and to illustrate a practical and robust solution. The PAH data detected in the sediment cores from the Illinois River provide the basis of this study. Principal component analysis (PCA) separates PAH compounds into two groups reflecting their possible airborne transport patterns; but it is not able to suggest specific sources. Not all positive matrix factorization (PMF) determined sources are distinguishable due to the variability of source fingerprints. However, they constitute useful suggestions for inputs for a Bayesian chemical mass balance (CMB) analysis. The Bayesian CMB analysis takes into account the measurement errors as well as the variations of source fingerprints, and provides a credible source apportionment. Major PAH sources for Illinois River sediments are traffic (35%), coke oven (24%), coal combustion (18%), and wood combustion (14%). PMID:26208321

  19. Overview of the Lombardy Region (I) Source Apportionment Study

    Science.gov (United States)

    Larsen, B. R.

    2009-04-01

    The Lombardia Region (RL) is situated in the central part of the Po Plain (I) where the mesoscale climatological conditions are determined to a high degree by the orographical characteristics of this area. Encirclement from three sides (North, West and South) by the mountain chains contributes greatly to the climatological peculiarities that are related from the physical point of view to the dynamic of the air mass in this region. The adverse anemological regime and the persistence of atmospheric stability result in low wind speeds, inversion of the temperature, and shallow inversion layers. Due to these particular geographical and the meteorological conditions associated with a high population density (9 million inhabitants) and the connected anthropogenic activities, RL is one of Europe's most polluted regions with regard to PM and photochemical smog. The 24 hours EU air quality limit for PM10 of 50 ug/m3 is exceeded up to 180 days per year and the yearly limit of 40 ug/m3 is in breach for most urban/urban background areas. In order to efficiently plan abatement strategies, quantitative information is required on the pollution sources and available emission inventories need to be compared with source apportionment results derived by receptor modeling of the chemical composition of PM10 in ambient air and in source emissions. The European Commission Joint Research Centre (JRC) has embarked on a major integrated project in RL (2006-2010) in collaboration with the air quality authorities (ARPA) to support the design of appropriate air quality and emission reduction strategies in this area. The present paper presents the first results of this project, carried out during typical winter episodes in 2007 at ten measurement stations distributed over the entire RL. The source contributions to PM10 and the associated air toxics (benzo[a]pyrene, Pb, Ni, Cd and As) have been quantified by Chemical Mass Balance and Positive Matrix Factorization based upon the chemical

  20. Effects of the Formula for Common Consolidated Corporate Tax Base Apportionment

    Directory of Open Access Journals (Sweden)

    Gheorghe MATEI

    2010-10-01

    Full Text Available For solving the existing difficulties in corporate income taxation, the European Commission proposed the introduction of measures for coordination, solution contested by some Member States but supported by most professionals and many organizations representing the interests of European employers. Disputes in connection with the introduction of the “Common Consolidated Corporate Tax Base” system are determined by the uncertainty regarding its effects. In this context, we intend to present and analyze some effects of applying the EU formula apportionment.

  1. Formulary Apportionment in the U.S. International Income Tax System: Putting Lipstick on a Pig?

    OpenAIRE

    Shay, Stephen E.; Fleming, J. Clifton, Jr.; Peroni, Robert J.

    2015-01-01

    Perhaps surprisingly, this Article has shown that the debate over formulary apportionment is little more than an alternative path to the larger debate over worldwide taxation versus territorial taxation. The present U.S. international income tax regime for U.S. MNEs is an implicit, overly-generous, and incoherent quasi-territorial system that relies on residence rules, source rules, and the arm’s-length approach to apportion international business profits between domestic income that is curre...

  2. Study on the Current Situation and Source Apportionment of PM2.5Pollution in China

    Institute of Scientific and Technical Information of China (English)

    Nianliang; CHENG; Shangyin; GAO; Yunting; LI; Bingfen; CHENG; Kuikui; YUAN

    2015-01-01

    In this paper,using concentration data of PM2. 5in 2013 in China and referring to a lot of literature,we preliminary studied the pollution of fine particulate matter and summarized PM2. 5source apportionment in the key cities in China. Our results showed that PM2. 5showed significant spatial and temporal distribution; high surface concentrations of PM2. 5concentrated mainly in the North China Plain,the Sichuan Basin,Yangtze River Delta and other regions; the average annual concentration of PM2. 5was about 80μg / m3 in North China Plain; Seasonal changes in the concentration of PM2. 5was winter > spring > autumn > summer; fired sources,industrial sources,vehicle exhaust were the major sources of PM2. 5; motor vehicle exhaust mostly contributed 10%- 30% to PM2. 5. This review provides a fundamental understanding of PM2. 5source apportionment and serves as an important reference for future source apportionment studies to be widely conducted in China.

  3. Primary and secondary organic aerosol origin by combined gas-particle phase source apportionment

    Directory of Open Access Journals (Sweden)

    M. Crippa

    2013-08-01

    Full Text Available Secondary organic aerosol (SOA, a prominent fraction of particulate organic mass (OA, remains poorly constrained. Its formation involves several unknown precursors, formation and evolution pathways and multiple natural and anthropogenic sources. Here a combined gas-particle phase source apportionment is applied to wintertime and summertime data collected in the megacity of Paris in order to investigate SOA origin during both seasons. This was possible by combining the information provided by an aerosol mass spectrometer (AMS and a proton transfer reaction mass spectrometer (PTR-MS. A better constrained apportionment of primary OA (POA sources is also achieved using this methodology, making use of gas-phase tracers. These tracers made possible the discrimination between biogenic and continental/anthropogenic sources of SOA. We found that continental SOA was dominant during both seasons (24–50% of total OA, while contributions from photochemistry-driven SOA (9% of total OA and marine emissions (13% of total OA were also observed during summertime. A semi-volatile nighttime component was also identified (up to 18% of total OA during wintertime. This approach was successfully applied here and implemented in a new source apportionment toolkit.

  4. 50 CFR Table 35 to Part 679 - Apportionment of Crab PSC and Halibut PSC Between the Amendment 80 and BSAI Trawl Limited Access...

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Apportionment of Crab PSC and Halibut PSC... 35 to Part 679—Apportionment of Crab PSC and Halibut PSC Between the Amendment 80 and BSAI Trawl Limited Access Sectors Fishery Year Halibut PSC limit in the BSAI Zone 1 Red king crab PSC limit . . ....

  5. Short analysis of the increase of the EEG apportionment 2013; Kurzanalyse des Anstiegs der EEG-Umlage 2013

    Energy Technology Data Exchange (ETDEWEB)

    Loreck, Charlotte; Matthes, Felix C.; Hermann, Hauke; Jung, Frederieke; Emele, Lukas

    2012-10-15

    At 15th October, 2012 the transmission system operators had published the EEG apportionment (EEG - Energy Economy Law). For the year 2013. This apportionment amounts 5,277 ct/kWh for non-privileged consumers in comparison to 3,59 ct/kWh for the year 2012. The ongoing enhancement of the renewable energies increases the EEG apportionment by an amount of 0.74 ct/kWh. With 0.26 ct/kWh the photovoltaics has the largest proportion in comparison to photovoltaics. The power generation from biomass as well as from wind energy at onshore sites contribute with 0.21 ct/kWh to the EEG apportionment. The greatest item of 0.48 ct/kWh is the debit balancing of the EEG account. The liquidity reserve for the year 2013 will be enhanced to 10% of the budget deficit. The expansion of the privileged status of the power consumption increases the EEG apportionment by 0.12 ct/kWh.

  6. Microbial water pollution: a screening tool for initial catchment-scale assessment and source apportionment.

    Science.gov (United States)

    Kay, D; Anthony, S; Crowther, J; Chambers, B J; Nicholson, F A; Chadwick, D; Stapleton, C M; Wyer, M D

    2010-11-01

    The European Union Water Framework Directive requires that Management Plans are developed for individual River Basin Districts. From the point of view of faecal indicator organisms (FIOs), there is a critical need for screening tools that can provide a rapid assessment of the likely FIO concentrations and fluxes within catchments under base- and high-flow conditions, and of the balance ('source apportionment') between agriculture- and sewage-derived sources. Accordingly, the present paper reports on: (1) the development of preliminary generic models, using water quality and land cover data from previous UK catchment studies for assessing FIO concentrations, fluxes and source apportionment within catchments during the summer bathing season; (2) the calibration of national land use data, against data previously used in the models; and (3) provisional FIO concentration and source-apportionment assessments for England and Wales. The models clearly highlighted the crucial importance of high-flow conditions for the flux of FIOs within catchments. At high flow, improved grassland (and associated livestock) was the key FIO source; FIO loadings derived from catchments with high proportions of improved grassland were shown to be as high as from urbanized catchments; and in many rural catchments, especially in NW and SW England and Wales, which are important areas of lowland livestock (especially dairy) farming, ≥ 40% of FIOs was assessed to be derived from agricultural sources. In contrast, under base-flow conditions, when there was little or no runoff from agricultural land, urban (i.e. sewerage-related) sources were assessed to dominate, and even in rural areas the majority of FIOs were attributed to urban sources. The results of the study demonstrate the potential of this type of approach, particularly in light of climate change and the likelihood of more high-flow events, in underpinning informed policy development and prioritization of investment. PMID:19717181

  7. Temporal trend and source apportionment of water pollution in different functional zones of Qiantang River, China.

    Science.gov (United States)

    Su, Shiliang; Li, Dan; Zhang, Qi; Xiao, Rui; Huang, Fang; Wu, Jiaping

    2011-02-01

    The increasingly serious river water pollution in developing countries poses great threat to environmental health and human welfare. The assignment of river function to specific uses, known as zoning, is a useful tool to reveal variations of water environmental adaptability to human impact. Therefore, characterizing the temporal trend and identifying responsible pollution sources in different functional zones could greatly improve our knowledge about human impacts on the river water environment. The aim of this study is to obtain a deeper understanding of temporal trends and sources of water pollution in different functional zones with a case study of the Qiantang River, China. Measurement data were obtained and pretreated for 13 variables from 41 monitoring sites in four categories of functional zones during the period 1996-2004. An exploratory approach, which combines smoothing and non-parametric statistical tests, was applied to characterize trends of four significant parameters (permanganate index, ammonia nitrogen, total cadmium and fluoride) accounting for differences among different functional zones identified by discriminant analysis. Aided by GIS, yearly pollution index (PI) for each monitoring site was further mapped to compare the within-group variations in temporal dynamics for different functional zones. Rotated principal component analysis and receptor model (absolute principle component score-multiple linear regression, APCS-MLR) revealed that potential pollution sources and their corresponding contributions varied among the four functional zones. Variations of APCS values for each site of one functional zone as well as their annual average values highlighted the uncertainties associated with cross space-time effects in source apportionment. All these results reinforce the notion that the concept of zoning should be taken seriously in water pollution control. Being applicable to other rivers, the framework of management-oriented source apportionment

  8. Testing the niche apportionment hypothesis with parasite communities: is random assortment always the rule?

    Science.gov (United States)

    Muñoz, G; Mouillot, D; Poulin, R

    2006-05-01

    Niche apportionment models have only been applied once to parasite communities. Only the random assortment model (RA), which indicates that species abundances are independent from each other and that interspecific competition is unimportant, provided a good fit to 3 out of 6 parasite communities investigated. The generality of this result needs to be validated, however. In this study we apply 5 niche apportionment models to the parasite communities of 14 fish species from the Great Barrier Reef. We determined which model fitted the data when using either numerical abundance or biomass as an estimate of parasite abundance, and whether the fit of niche apportionment models depends on how the parasite community is defined (e.g. ecto, endoparasites or all parasites considered together). The RA model provided a good fit for the whole community of parasites in 7 fish species when using biovolume (as a surrogate of biomass) as a measure of species abundance. The RA model also fitted observed data when ecto- and endoparasites were considered separately, using abundance or biovolume, but less frequently. Variation in fish sizes among species was not associated with the probability of a model fitting the data. Total numerical abundance and biovolume of parasites were not related across host species, suggesting that they capture different aspects of abundance. Biovolume is not only a better measurement to use with niche-orientated models, it should also be the preferred descriptor to analyse parasite community structure in other contexts. Most of the biological assumptions behind the RA model, i.e. randomness in apportioning niche space, lack of interspecific competition, independence of abundance among different species, and species with variable niches in changeable environments, are in accordance with some previous findings on parasite communities. Thus, parasite communities may generally be unsaturated with species, with empty niches, and interspecific interactions may

  9. Application of a source apportionment model in consideration of volatile organic compounds in an urban stream

    Science.gov (United States)

    Asher, W.E.; Luo, W.; Campo, K.W.; Bender, D.A.; Robinson, K.W.; Zogorski, J.S.; Pankow, J.F.

    2007-01-01

    Position-dependent concentrations of trichloroethylene and methyl-tert-butyl ether are considered for a 2.81-km section of the Aberjona River in Massachusetts, USA. This river flows through Woburn and Winchester (Massachusetts, USA), an area that is highly urbanized, has a long history of industrial activities dating to the early 1800s, and has gained national attention because of contamination from chlorinated solvent compounds in Woburn wells G and H. The river study section is in Winchester and begins approximately five stream kilometers downstream from the Woburn wells superfund site. Approximately 300 toxic release sites are documented in the watershed upstream from the terminus of the study section. The inflow to the river study section is considered one source of contamination. Other sources are the atmosphere, a tributary flow, and groundwater flows entering the river; the latter are categorized according to stream zone (1, 2, 3, etc.). Loss processes considered include outflows to groundwater and water-to-atmosphere transfer of volatile compounds. For both trichloroethylene and methyl-rerf-butyl ether, degradation is neglected over the timescale of interest. Source apportionment fractions with assigned values ??inflow, ??1, ??2, ??3, etc. are tracked by a source apportionment model. The strengths of the groundwater and tributary sources serve as fitting parameters when minimizing a reduced least squares statistic between water concentrations measured during a synoptic study in July 2001 versus predictions from the model. The model fits provide strong evidence of substantial unknown groundwater sources of trichloroethylene and methyl-tert-butyl ether amounting to tens of grams per day of trichloroethylene and methyl-tert-butyl ether in the river along the study section. Modeling in a source apportionment manner can be useful to water quality managers allocating limited resources for remediation and source control. ?? 2007 SETAC.

  10. Trends in PM2.5 emissions, concentrations and apportionments in Detroit and Chicago

    Science.gov (United States)

    Milando, Chad; Huang, Lei; Batterman, Stuart

    2016-03-01

    PM2.5 concentrations throughout much of the U.S. have decreased over the last 15 years, but emissions and concentration trends can vary by location and source type. Such trends should be understood to inform air quality management and policies. This work examines trends in emissions, concentrations and source apportionments in two large Midwest U.S. cities, Detroit, Michigan, and Chicago, Illinois. Annual and seasonal trends were investigated using National Emission Inventory (NEI) data for 2002 to 2011, speciated ambient PM2.5 data from 2001 to 2014, apportionments from positive matrix factorization (PMF) receptor modeling, and quantile regression. Over the study period, county-wide data suggest emissions from point sources decreased (Detroit) or held constant (Chicago), while emissions from on-road mobile sources were constant (Detroit) or increased (Chicago), however changes in methodology limit the interpretation of inventory trends. Ambient concentration data also suggest source and apportionment trends, e.g., annual median concentrations of PM2.5 in the two cities declined by 3.2-3.6%/yr (faster than national trends), and sulfate concentrations (due to coal-fired facilities and other point source emissions) declined even faster; in contrast, organic and elemental carbon (tracers of gasoline and diesel vehicle exhaust) declined more slowly or held constant. The PMF models identified nine sources in Detroit and eight in Chicago, the most important being secondary sulfate, secondary nitrate and vehicle emissions. A minor crustal dust source, metals sources, and a biomass source also were present in both cities. These apportionments showed that the median relative contributions from secondary sulfate sources decreased by 4.2-5.5% per year in Detroit and Chicago, while contributions from metals sources, biomass sources, and vehicles increased from 1.3 to 9.2% per year. This first application of quantile regression to trend analyses of speciated PM2.5 data reveals

  11. The key indicators of transboundary water apportionment based on international laws and cases

    Institute of Scientific and Technical Information of China (English)

    FENG Yan; HE Daming; LI Yungang

    2013-01-01

    Transboundary water,more competitive utilization and uncertain availability under the globalization trend,the issue of its apportionment which directly impacts national benefits of each riparian state is becoming one of the important topics in the world.Water is scarce in China,the most important upstream state in Asia,and this task has to be thought over in the coming future.Based on “International Freshwater Treaties Database” (1820-2007) by Oregon State University,and publications and reports on transboundary water utilization and management since 1999,28 indicators of water apportionment adopted in 49 international treaties and cases in 1864-2002 are divided into 6 types,the spatial and temporal characteristics of the adopted indicators are analyzed in order to find the key indicator(s) of transboundary water apportionment.The major results include:the major adopted indicators,have significant differences among 5 regions/continents,the indicators at rank first and second place in the developed region (North America and Europe) according to the adopted times are “keeping minimum water flow” and “mean annual runoff”,but in the developing region (Asia,Africa and South America),the ranking order of the above two indicators is reversed; the major adopted indicators in the watersheds with insufficient water are “mean annual runoff”and “keeping minimum water flow”,the ones in the watersheds with sufficient water are “keeping minimum water flow” and “maximum water intake”; the international treaties signed from the first phase to the fourth phase,the developing process shows a progress of “fewer-increasing a lot-decreasing rapidly-equation basically”,the regional distribution of the treaties shifts mainly from the developed region to the developing one,especially to Asia and Africa; the major adopted indicators shifts from “keeping minimum water flow” and “mean annual runoff” in 1864-1945,to “keeping minimum water flow” and

  12. Radon source apportionment in the home, dosimetry and risk modeling. Final report, 1993--1997

    Energy Technology Data Exchange (ETDEWEB)

    Harley, N.H.

    1998-08-04

    This research covered the following 3 topics in 4 years: (1) the source apportionment of {sup 222}Rn in the home; (2) the internal bronchial dosimetry of inhaled {sup 222}Rn decay products; and (3) the lung cancer risk from inhalation of the short lived decay products of {sup 222}Rn. A 4th year of support was appended to this grant with a switch in research effort to determine a method for long term measurement of the particle size distribution of the short lived decay products in homes.

  13. Source Contributions to Wintertime Elemental and Organic Carbon in the Western Arctic Based on Radiocarbon and Tracer Apportionment.

    Science.gov (United States)

    Barrett, T E; Robinson, E M; Usenko, S; Sheesley, R J

    2015-10-01

    To quantify the contributions of fossil and biomass sources to the wintertime Arctic aerosol burden source apportionment is reported for elemental (EC) and organic carbon (OC) fractions of six PM10 samples collected during a wintertime (2012-2013) campaign in Barrow, AK. Radiocarbon apportionment of EC indicates that fossil sources contribute an average of 68 ± 9% (0.01-0.07 μg m(-3)) in midwinter decreasing to 49 ± 6% (0.02 μg m(-3)) in late winter. The mean contribution of fossil sources to OC for the campaign was stable at 38 ± 8% (0.04-0.32 μg m(-3)). Samples were also analyzed for organic tracers, including levoglucosan, for use in a chemical mass balance (CMB) source apportionment model. The CMB model was able to apportion 24-53% and 99% of the OC and EC burdens, respectively, during the campaign, with fossil OC contributions ranging from 25 to 74% (0.02-0.09 μg m(-3)) and fossil EC contributions ranging from 73 to 94% (0.03-0.07 μg m(-3)). Back trajectories identified two major wintertime source regions to Barrow: the Russian and North American Arctic. Atmospheric lifetimes of levoglucosan, ranging from 50 to 320 h, revealed variability in wintertime atmospheric processing of this biomass burning tracer. This study allows for unambiguous apportionment of EC to fossil fuel and biomass combustion sources and intercomparison with CMB modeling. PMID:26325404

  14. A novel approach for apportionment between primary and secondary sources of airborne nitrated polycyclic aromatic hydrocarbons (NPAHs)

    Science.gov (United States)

    Lin, Yan; Qiu, Xinghua; Ma, Yiqiu; Wang, Junxia; Wu, Yusheng; Zeng, Limin; Hu, Min; Zhu, Tong; Zhu, Yifang

    2016-08-01

    Nitrated polycyclic aromatic hydrocarbons (NPAHs) are strong environmental mutagens and carcinogens originating from both primary emissions and secondary reactions in the atmosphere. The sources and the toxicity of different NPAH species could vary greatly; therefore a specie-specific source apportionment is essential to evaluate their health risks and to formulate controlling regulations. However, few studies have reported source apportionment of NPAHs species to date. In this study, we developed an easy-to-perform method for the apportionment of primary versus secondary sources of airborne NPAHs based on the relationship between NPAHs and NO2. After log-transformation of both NPAHs and NO2 concentrations, a slope of β between these two variables was obtained by the linear regression. When β is significantly smaller than 1, it indicates primary emissions while β significantly greater than 1 suggests secondary formation. We have validated this method with data previously collected in Beijing. A good correlation, with R value of 0.57, was observed between results produced by this new method and by Positive Matrix Factorization (PMF). The correlation could be further improved (R = 0.71) if the gas/particle partition of NPAHs is taken into consideration. This developed method enables the source apportionment for individual NPAHs species and could be used to validate the results of other receptor models.

  15. SOURCE APPORTIONMENT OF PM 2.5 AND CARBON IN SEATTLE USING CHEMICAL MASS BALANCE AND POSITIVE MATRIX FACTORIZATION

    Science.gov (United States)

    Three years of PM2.5 speciated data were collected and chemically analyzed using the IMPROVE protocol at the Beacon Hill site in Seattle. The data were analyzed by the Chemical Mass Balance Version 8 (CMB8) and Positive Matrix Factorization (PMF) source apportionment models. T...

  16. Source Apportionment of Sulfate and Nitrate over the Pearl River Delta Region in China

    Directory of Open Access Journals (Sweden)

    Xingcheng Lu

    2016-07-01

    Full Text Available In this work, the Weather Research Forecast (WRF–Sparse Matrix Operator Kernel Emission (SMOKE–Comprehensive Air Quality Model with Extensions (CAMx modeling system with particulate source apportionment technology (PSAT module was used to study and analyze the source apportionment of sulfate and nitrate particulate matter in the Pearl River Delta region (PRD. The results show that superregional transport was an important contributor for both sulfates and nitrates in all 10 cities in this region in both February (winter and August (summer. Especially in February, the average super-regional contribution of sulfate and nitrate reached up to 80% and 56% respectively. For the local and regional source category, power plant emissions (coal-fired and oil-fired and industry emissions were important for sulfate formation in this region. Industry emissions and mobile emissions are important for nitrate formation in this region. In August, the sum of these two sources contributed around over 60% of local and regional nitrate. The contributions from power plant emissions and marine emissions became important in August due to the southerly prevailing wind direction. Area sources and biogenic emissions were negligible for sulfate and nitrate formation in this region. Our results reveal that cross-province cooperation is necessary for control of sulfates and nitrates in this region.

  17. Source Apportionment of PM2.5 in Delhi, India Using PMF Model.

    Science.gov (United States)

    Sharma, S K; Mandal, T K; Jain, Srishti; Saraswati; Sharma, A; Saxena, Mohit

    2016-08-01

    Chemical characterization of PM2.5 [organic carbon, elemental carbon, water soluble inorganic ionic components, and major and trace elements] was carried out for a source apportionment study of PM2.5 at an urban site of Delhi, India from January, 2013, to December, 2014. The annual average mass concentration of PM2.5 was 122 ± 94.1 µg m(-3). Strong seasonal variation was observed in PM2.5 mass concentration and its chemical composition with maxima during winter and minima during monsoon. A receptor model, positive matrix factorization (PMF) was applied for source apportionment of PM2.5 mass concentration. The PMF model resolved the major sources of PM2.5 as secondary aerosols (21.3 %), followed by soil dust (20.5 %), vehicle emissions (19.7 %), biomass burning (14.3 %), fossil fuel combustion (13.7 %), industrial emissions (6.2 %) and sea salt (4.3 %). PMID:27209541

  18. An integrated approach to assess heavy metal source apportionment in peri-urban agricultural soils.

    Science.gov (United States)

    Huang, Ying; Li, Tingqiang; Wu, Chengxian; He, Zhenli; Japenga, Jan; Deng, Meihua; Yang, Xiaoe

    2015-12-15

    Three techniques (Isotope Ratio Analysis, GIS mapping, and Multivariate Statistical Analysis) were integrated to assess heavy metal pollution and source apportionment in peri-urban agricultural soils. The soils in the study area were moderately polluted with cadmium (Cd) and mercury (Hg), lightly polluted with lead (Pb), and chromium (Cr). GIS Mapping suggested Cd pollution originates from point sources, whereas Hg, Pb, Cr could be traced back to both point and non-point sources. Principal component analysis (PCA) indicated aluminum (Al), manganese (Mn), nickel (Ni) were mainly inherited from natural sources, while Hg, Pb, and Cd were associated with two different kinds of anthropogenic sources. Cluster analysis (CA) further identified fertilizers, waste water, industrial solid wastes, road dust, and atmospheric deposition as potential sources. Based on isotope ratio analysis (IRA) organic fertilizers and road dusts accounted for 74-100% and 0-24% of the total Hg input, while road dusts and solid wastes contributed for 0-80% and 19-100% of the Pb input. This study provides a reliable approach for heavy metal source apportionment in this particular peri-urban area, with a clear potential for future application in other regions. PMID:26257294

  19. Source Apportionment of Heavy Metals in Soils Using Multivariate Statistics and Geostatistics

    Institute of Scientific and Technical Information of China (English)

    QU Ming-Kai; LI Wei-Dong; ZHANG Chuan-Rong; WANG Shan-Qin; YANG Yong; HE Li-Yuan

    2013-01-01

    The main objectives of this study were to introduce an integrated method for effectively identifying soil heavy metal pollution sources and apportioning their contributions,and apply it to a case study.The method combines the principal component analysis/absolute principal component scores (PCA/APCS) receptor model and geostatistics.The case study was conducted in an area of 31 km2 in the urban-rural transition zone of Wuhan,a metropolis of central China.124 topsoil samples were collected for measuring the concentrations of eight heavy metal elements (Mn,Cu,Zn,Pb,Cd,Cr,Ni and Co).PCA results revealed that three major factors were responsible for soil heavy metal pollution,which were initially identified as "steel production","agronomic input" and "coal consumption".The APCS technique,combined with multiple linear regression analysis,was then applied for source apportionment.Steel production appeared to be the main source for Ni,Co,Cd,Zn and Mn,agronomic input for Cu,and coal consumption for Pb and Cr.Geostatistical interpolation using ordinary kriging was finally used to map the spatial distributions of the contributions of pollution sources and further confirm the result interpretations.The introduced method appears to be an effective tool in soil pollution source apportionment and identification,and might provide valuable reference information for pollution control and environmental management.

  20. Quantitative back-trajectory apportionment of sources of particulate sulfate at Big Bend National Park, TX

    Science.gov (United States)

    Gebhart, Kristi A.; Schichtel, Bret A.; Barna, Michael G.; Malm, William C.

    As part of the Big Bend Regional Aerosol and Visibility Observational (BRAVO) study, a quantitative back-trajectory-based receptor model, Trajectory Mass Balance (TrMB) was used to estimate source apportionment of particulate sulfur measured at Big Bend National Park, Texas, during July-October 1999. The model was exercised using a number of sets of trajectories generated by three different trajectory models, with three different sets of input gridded meteorology, and tracked for 5, 7, and 10 days back in time. The performance of the TrMB model with the different trajectory inputs was first evaluated against perfluorocarbon tracers and synthetically generated sulfate concentrations from a regional air quality model, both of which had known attributions. These tests were used to determine which trajectories were adequate for the TrMB modeling of measured sulfate concentrations, illustrated the magnitude of the daily uncertainties as compared to the uncertainties in the mean attributions, and demonstrated the value of a robust evaluation process. Depending on trajectories, mean sulfate source apportionment results were 39-50% from Mexico, 7-26% from the eastern US, 12-45% from Texas, and 3-25% from the western US. These ranges were inclusive of the best BRAVO attribution estimates for Mexico, Texas, and the western US, but TrMB underestimated the eastern US contribution as compared to the BRAVO best estimates.

  1. An integrated PM2.5 source apportionment study: Positive Matrix Factorisation vs. the chemical transport model CAMx

    Science.gov (United States)

    Bove, M. C.; Brotto, P.; Cassola, F.; Cuccia, E.; Massabò, D.; Mazzino, A.; Piazzalunga, A.; Prati, P.

    2014-09-01

    Receptor and Chemical Transport Models are commonly used tools in source apportionment studies, even if different expertise is required. We describe an experiment using both approaches to apportion the PM2.5 (i.e., particulate matter with aerodynamic diameters below 2.5 μm) sources in the city of Genoa (Italy). A sampling campaign was carried out to collect PM2.5 samples daily for approximately six month during 2011 in three sites. The subsequent compositional analyses included the speciation of elements, major ions and both organic and elemental carbon; these data produced a large database for receptor modelling through Positive Matrix Factorisation (PMF). In the same period, a meteorological and air quality modelling system was implemented based on the mesoscale numerical weather prediction model WRF and the chemical transport model CAMx to obtain meteorological and pollutant concentrations up to a resolution of 1.1 km. The source apportionment was evaluated by CAMx over the same period that was used for the monitoring campaign using the Particulate Source Apportionment Technology tool. Even if the source categorisations were changed (i.e., groups of time-correlated compounds in PMF vs. activity categories in CAMx), the PM2.5 source apportionment by PMF and CAMx produced comparable results. The different information provided by the two approaches (e.g., real-world factor profile by PMF and apportionment of a secondary aerosol by CAMx) was used jointly to elucidate the composition and origin of PM2.5 and to develop a more general methodology. When studying the primary and secondary components of PM, the main anthropogenic sources in the area were road transportation, energy production/industry and maritime emissions, accounting for 40%-50%, 20%-30% and 10%-15%, of PM2.5, respectively.

  2. The Analysis of PM2.5 Source Apportionment Technique's Competitiveness in China

    Science.gov (United States)

    Qian, K.; Deng, L.; An, Y. B.; Liu, S. Y.; Hao, H. Z.

    Nowadays, people has paid more attention to PM2.5 in various countries of the world. PM2.5 is a kind of particulate matter whose diameter less than 2.5μm, with great damage to environment and public's health. The origin of source apportionment technique is studies of atmospheric particulate matter, it uses two mathematical models, one of them is diffusion model which study the source of pollution, and another one called receptor model which study the pollution of area. In my study, I will analyze the competitiveness of similar technology in various countries by using microscope to analyze shape characteristic, Enrichment Factor Method (EF), Factor Analyze Method (FA), EPA-CMB8.2 Model, combining with the consequence of Improved-source-analysis Technology and Orthogonal matrix decomposition Model.

  3. Source apportionment for urban PM10 and PM2.5 in the Beijing area

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wei; GUO JingHua; SUN YeLe; YUAN Hui; ZHUANG GuoShun; ZHUANG YaHui; HAO ZhengPing

    2007-01-01

    Airborne particulate matter (PM2.5 and PM10) samples were collected at the Beijing Normal University sampling site in the urban area of Beijing, China in dry and wet seasons during 2001―2004. Concentrations of 23 elements and 14 ions in particulate samples were determined by ICP-AES and IC, respectively. Source apportionment results derived from both Positive Matrix Factorization (PMF) and Chemical Mass Balance (CMB) models indicate that the major contributors of PM2.5 and PM10 in Beijing are: soil dust, fossil fuel combustion, vehicle exhausts, secondary particulate, biomass burning and some industrial sources. We have identified both regional common sources, such as vehicular emissions, particulate of secondary origin and biomass burning, as well as country-specific problems, such as sand storms and soil dust that should be addressed for effective air quality control.

  4. Contamination characteristics and source apportionment of trace metals in soils around Miyun Reservoir.

    Science.gov (United States)

    Chen, Haiyang; Teng, Yanguo; Chen, Ruihui; Li, Jiao; Wang, Jinsheng

    2016-08-01

    Due to their toxicity and bioaccumulation, trace metals in soils can result in a wide range of toxic effects on animals, plants, microbes, and even humans. Recognizing the contamination characteristics of soil metals and especially apportioning their potential sources are the necessary preconditions for pollution prevention and control. Over the past decades, several receptor models have been developed for source apportionment. Among them, positive matrix factorization (PMF) has gained popularity and was recommended by the US Environmental Protection Agency as a general modeling tool. In this study, an extended chemometrics model, multivariate curve resolution-alternating least squares based on maximum likelihood principal component analysis (MCR-ALS/MLPCA), was proposed for source apportionment of soil metals and applied to identify the potential sources of trace metals in soils around Miyun Reservoir. Similar to PMF, the MCR-ALS/MLPCA model can incorporate measurement error information and non-negativity constraints in its calculation procedures. Model validation with synthetic dataset suggested that the MCR-ALS/MLPCA could extract acceptable recovered source profiles even considering relatively larger error levels. When applying to identify the sources of trace metals in soils around Miyun Reservoir, the MCR-ALS/MLPCA model obtained the highly similar profiles with PMF. On the other hand, the assessment results of contamination status showed that the soils around reservoir were polluted by trace metals in slightly moderate degree but potentially posed acceptable risks to the public. Mining activities, fertilizers and agrochemicals, and atmospheric deposition were identified as the potential anthropogenic sources with contributions of 24.8, 14.6, and 13.3 %, respectively. In order to protect the drinking water source of Beijing, special attention should be paid to the metal inputs to soils from mining and agricultural activities. PMID:27107989

  5. Quantification and radiocarbon source apportionment of black carbon in atmospheric aerosols using the CTO-375 method

    Science.gov (United States)

    Zencak, Zdenek; Elmquist, Marie; Gustafsson, Örjan

    To make progress towards linking the atmosphere and biogeosphere parts of the black carbon (BC) cycle, a chemothermal oxidation method (CTO-375), commonly applied for isolating BC from complex geomatrices such as soils, sediments and aquatic particles, was applied to investigate the BC also in atmospheric particles. Concentrations and 14C-based source apportionment of CTO-375 based BC was established for a reference aerosol (NIST RM-8785) and for wintertime aerosols collected in Stockholm and in a Swedish background area. The results were compared with thermal-optical (OC/EC) measurements. For NIST RM-8785, a good agreement was found between the BC CTO-375 concentration and the reported elemental carbon (EC) concentration measured by the "Speciation Trends Network—National Institute of Occupational Safety and Health" method (EC NIOSH) with BC CTO-375 of 0.054±0.002 g g -1 and EC NIOSH of 0.067±0.008 g g -1. In contrast, there was an average factor of ca. 20 difference between BC CTO-375 and EC NIOSH for the ambient Scandinavian wintertime aerosols, presumably reflecting a combination of BC CTO-375 isolating only the recalcitrant soot-BC portion of the BC continuum and the EC NIOSH metric inadvertently including some intrinsically non-pyrogenic organic matter. Isolation of BC CTO-375 with subsequent off-line radiocarbon analysis yielded fraction modern values (fM) for total organic carbon (TOC) of 0.93 (aerosols from a Swedish background area), and 0.58 (aerosols collected in Stockholm); whereas the fM for BC CTO-375 isolates were 1.08 (aerosols from a Swedish background area), and 0.87 (aerosols collected in Stockholm). This radiocarbon-based source apportionment suggests that contribution from biomass combustion to cold-season atmospheric BC CTO-375 in Stockholm was 70% and in the background area 88%.

  6. Isotope source apportionment of carbonaceous aerosol as a function of particle size and thermal refractiveness

    Science.gov (United States)

    Masalaite, Agne; Holzinger, Rupert; Remeikis, Vidmantas; Röckmann, Thomas; Dusek, Ulrike

    2016-04-01

    The stable carbon isotopes can be used to get information about sources and processing of carbonaceous aerosol. We will present results from source apportionment of carbonaceous aerosol as a function of particle size thermal refractiveness. Separate source apportionment for particles smaller than 200 nm and for different carbon volatility classes are rarely reported and give new insights into aerosol sources in the urban environment. Stable carbon isotope ratios were measured for the organic carbon (OC) fraction and total carbon (TC) of MOUDI impactor samples that were collected on a coastal site (Lithuania) during the winter 2012 and in the city of Vilnius (Lithuania) during the winter of 2009. The 11 impactor stages spanned a size range from 0.056 to 18 μm, but only the 6 stages in the submicron range were analysed. The δ13C values of bulk total carbon (δ13CTC) were determined with an elemental analyser (Flash EA 1112) coupled with an isotope ratio mass spectrometer (Thermo Finnigan Delta Plus Advantage) (EA - IRMS). Meanwhile δ13COC was measured using thermal-desorption isotope ratio mass spectrometry (IRMS) system. This allows a rough separation of the more volatile OC fraction (desorbed in the oven of IRMS up to 250 0C) from the more refractory fraction (desorbed up to 400 0C). In this study we investigated the composition of organic aerosol desorbed from filter samples at different temperatures using the thermal-desorption proton-transfer-reaction mass spectrometry (TD-PTR-MS) technique. During winter-time in Lithuania we expect photochemistry and biogenic emissions to be of minor importance. The main sources of aerosol carbon should be fossil fuel and biomass combustion. In both sites, the coastal and the urban site, δ13C measurements give a clear indication that the source contributions differ for small and large particles. Small particles grants Nr. 820.01.001, and 834.08.002).

  7. An inter-comparison of PM10 source apportionment using PCA and PMF receptor models in three European sites.

    Science.gov (United States)

    Cesari, Daniela; Amato, F; Pandolfi, M; Alastuey, A; Querol, X; Contini, D

    2016-08-01

    Source apportionment of aerosol is an important approach to investigate aerosol formation and transformation processes as well as to assess appropriate mitigation strategies and to investigate causes of non-compliance with air quality standards (Directive 2008/50/CE). Receptor models (RMs) based on chemical composition of aerosol measured at specific sites are a useful, and widely used, tool to perform source apportionment. However, an analysis of available studies in the scientific literature reveals heterogeneities in the approaches used, in terms of "working variables" such as the number of samples in the dataset and the number of chemical species used as well as in the modeling tools used. In this work, an inter-comparison of PM10 source apportionment results obtained at three European measurement sites is presented, using two receptor models: principal component analysis coupled with multi-linear regression analysis (PCA-MLRA) and positive matrix factorization (PMF). The inter-comparison focuses on source identification, quantification of source contribution to PM10, robustness of the results, and how these are influenced by the number of chemical species available in the datasets. Results show very similar component/factor profiles identified by PCA and PMF, with some discrepancies in the number of factors. The PMF model appears to be more suitable to separate secondary sulfate and secondary nitrate with respect to PCA at least in the datasets analyzed. Further, some difficulties have been observed with PCA in separating industrial and heavy oil combustion contributions. Commonly at all sites, the crustal contributions found with PCA were larger than those found with PMF, and the secondary inorganic aerosol contributions found by PCA were lower than those found by PMF. Site-dependent differences were also observed for traffic and marine contributions. The inter-comparison of source apportionment performed on complete datasets (using the full range of

  8. Source apportionment of size-segregated atmospheric particles based on the major water-soluble components in Lecce (Italy)

    Energy Technology Data Exchange (ETDEWEB)

    Contini, D., E-mail: d.contini@isac.cnr.it [Istituto di Scienze dell' Atmosfera e del Clima, ISAC-CNR, Lecce (Italy); Cesari, D. [Istituto di Scienze dell' Atmosfera e del Clima, ISAC-CNR, Lecce (Italy); Genga, A.; Siciliano, M. [Dipartimento di Scienze e Tecnologie Biologiche e Ambientali, Università del Salento, Lecce (Italy); Ielpo, P. [Istituto di Scienze dell' Atmosfera e del Clima, ISAC-CNR, Lecce (Italy); Istituto di Ricerca Sulle Acque, IRSA-CNR, Bari (Italy); Guascito, M.R. [Dipartimento di Scienze e Tecnologie Biologiche e Ambientali, Università del Salento, Lecce (Italy); Conte, M. [Istituto di Scienze dell' Atmosfera e del Clima, ISAC-CNR, Lecce (Italy)

    2014-02-01

    Atmospheric aerosols have potential effects on human health, on the radiation balance, on climate, and on visibility. The understanding of these effects requires detailed knowledge of aerosol composition and size distributions and of how the different sources contribute to particles of different sizes. In this work, aerosol samples were collected using a 10-stage Micro-Orifice Uniform Deposit Impactor (MOUDI). Measurements were taken between February and October 2011 in an urban background site near Lecce (Apulia region, southeast of Italy). Samples were analysed to evaluate the concentrations of water-soluble ions (SO{sub 4}{sup 2−}, NO{sub 3}{sup −}, NH{sub 4}{sup +}, Cl{sup −}, Na{sup +}, K{sup +}, Mg{sup 2+} and Ca{sup 2+}) and of water-soluble organic and inorganic carbon. The aerosols were characterised by two modes, an accumulation mode having a mass median diameter (MMD) of 0.35 ± 0.02 μm, representing 51 ± 4% of the aerosols and a coarse mode (MMD = 4.5 ± 0.4 μm), representing 49 ± 4% of the aerosols. The data were used to estimate the losses in the impactor by comparison with a low-volume sampler. The average loss in the MOUDI-collected aerosol was 19 ± 2%, and the largest loss was observed for NO{sub 3}{sup −} (35 ± 10%). Significant losses were observed for Ca{sup 2+} (16 ± 5%), SO{sub 4}{sup 2−} (19 ± 5%) and K{sup +} (10 ± 4%), whereas the losses for Na{sup +} and Mg{sup 2+} were negligible. Size-segregated source apportionment was performed using Positive Matrix Factorization (PMF), which was applied separately to the coarse (size interval 1–18 μm) and accumulation (size interval 0.056–1 μm) modes. The PMF model was able to reasonably reconstruct the concentration in each size-range. The uncertainties in the source apportionment due to impactor losses were evaluated. In the accumulation mode, it was not possible to distinguish the traffic contribution from other combustion sources. In the coarse mode, it was not possible to

  9. Source apportionment of the summer time carbonaceous aerosol at Nordic rural background sites

    Directory of Open Access Journals (Sweden)

    K. E. Yttri

    2011-12-01

    Full Text Available In the present study, natural and anthropogenic sources of particulate organic carbon (OCp and elemental carbon (EC have been quantified based on weekly filter samples of PM10 (particles with aerodynamic diameter <10 μm collected at four Nordic rural background sites [Birkenes (Norway, Hyytiälä (Finland, Vavihill (Sweden, Lille Valby, (Denmark] during late summer (5 August–2 September 2009. Levels of source specific tracers, i.e. cellulose, levoglucosan, mannitol and the 14C/12C ratio of total carbon (TC, have been used as input for source apportionment of the carbonaceous aerosol, whereas Latin Hypercube Sampling (LHS was used to statistically treat the multitude of possible combinations resulting from this approach. The carbonaceous aerosol (here: TCp; i.e. particulate TC was totally dominated by natural sources (69–86%, with biogenic secondary organic aerosol (BSOA being the single most important source (48–57%. Interestingly, primary biological aerosol particles (PBAP were the second most important source (20–32%. The anthropogenic contribution was mainly attributed to fossil fuel sources (OCff and ECff (10–24%, whereas no more than 3–7% was explained by combustion of biomass (OCbb and ECbb in this late summer campaign i.e. emissions from residential wood burning and/or wild/agricultural fires. Fossil fuel sources totally dominated the ambient EC loading, which accounted for 4–12% of TCp, whereas <1.5% of EC was attributed to combustion of biomass. The carbonaceous aerosol source apportionment showed only minor variation between the four selected sites. However, Hyytiälä and Birkenes showed greater resemblance to each other, as did Lille Valby and Vavihill, the two latter being somewhat more influenced by anthropogenic sources. Ambient levels of organosulphates and nitrooxy-organosulphates in the Nordic rural

  10. Source apportionment of the summer time carbonaceous aerosol at Nordic rural background sites

    Directory of Open Access Journals (Sweden)

    K. E. Yttri

    2011-06-01

    Full Text Available In the present study, natural and anthropogenic sources of particulate organic carbon (OCp and elemental carbon (EC have been quantified based on weekly filter samples of PM10 collected at four Nordic rural background sites (Birkenes (Norway, Hyytiälä (Finland Vavihill (Sweden, Lille Valby (Denmark during late summer (5 August–2 September 2009. Levels of source specific tracers, i.e. cellulose, levoglucosan, mannitol and the 14C/12C ratio of total carbon (TC, have been used as input for source apportionment of the carbonaceous aerosol, whereas Latin Hypercube Sampling (LHS was used to statistically treat the multitude of possible combinations resulting from this approach.

    The carbonaceous aerosol (here: TCp; i.e. particulate TC was totally dominated by natural sources (69–86 %, with biogenic secondary organic aerosol (BSOA being the single most important source (48–57 %. Interestingly, primary biological aerosol particles (PBAP were the second most important source (20–32 %. The anthropogenic contribution was mainly attributed to fossil fuel sources (OCff and ECff (10–24 %, whereas no more than 3–7 % was explained by combustion of biomass (OCbb and ECbb in this late summer campaign i.e. emissions from residential wood burning and/or wild/agricultural fires. Fossil fuel sources totally dominated the ambient EC loading, accounting for 4–12 % of TCp, whereas <1.5 % was attributed to combustion of biomass. The carbonaceous aerosol source apportionment showed only minor variation between the four selected sites. However, Hyytiälä and Birkenes showed greater resemblance to each other, as did Lille Valby and Vavihill, the two latter being somewhat more influenced by anthropogenic sources.

    Ambient levels of organosulphates and nitrooxy-organosulphates in the Nordic rural background environment are reported for

  11. A factor analysis-multiple regression model for source apportionment of suspended particulate matter

    Science.gov (United States)

    Okamoto, Shin'ichi; Hayashi, Masayuki; Nakajima, Masaomi; Kainuma, Yasutaka; Shiozawa, Kiyoshige

    A factor analysis-multiple regression (FA-MR) model has been used for a source apportionment study in the Tokyo metropolitan area. By a varimax rotated factor analysis, five source types could be identified: refuse incineration, soil and automobile, secondary particles, sea salt and steel mill. Quantitative estimations using the FA-MR model corresponded to the calculated contributing concentrations determined by using a weighted least-squares CMB model. However, the source type of refuse incineration identified by the FA-MR model was similar to that of biomass burning, rather than that produced by an incineration plant. The estimated contributions of sea salt and steel mill by the FA-MR model contained those of other sources, which have the same temporal variation of contributing concentrations. This symptom was caused by a multicollinearity problem. Although this result shows the limitation of the multivariate receptor model, it gives useful information concerning source types and their distribution by comparing with the results of the CMB model. In the Tokyo metropolitan area, the contributions from soil (including road dust), automobile, secondary particles and refuse incineration (biomass burning) were larger than industrial contributions: fuel oil combustion and steel mill. However, since vanadium is highly correlated with SO 42- and other secondary particle related elements, a major portion of secondary particles is considered to be related to fuel oil combustion.

  12. Characterization and source apportionment of particulate matter Indonesia, during a recent peat fire episode.

    Science.gov (United States)

    See, Siao Wei; Balasubramanian, Rajasekhar; Rianawati, Elisabeth; Karthikeyan, Sathrugnan; Streets, David G

    2007-05-15

    An intensive field study was conducted in Sumatra, Indonesia, during a peat fire episode to investigate the physical and chemical characteristics of particulate emissions in peat smoke and to provide necessary data for source-receptor analyses. Ambient air sampling was carried out at three different sites located at varying distances from the peatfires to determine changes in mass and number concentrations of PM2.5 and its chemical composition (carbonaceous and nitrogenous materials, polycyclic aromatic hydrocarbons, water-soluble inorganic and organic ions, and total and water-soluble metals). The three sites represent a rural site directly affected by the local peat combustion, a semirural site, and an urban site situated downwind of the peat fires. The mass concentration of PM2.5 and the number concentration of airborne particles were as high as 1600 microg/m3 and 1.7 x 10(5) cm(-3), respectively, in the vicinity of peat fires. The major components of PM2.5 in peat smoke haze were carbonaceous particles, particularly organic carbon, NO3-, and SO4(2-), while the less abundant constituents included ions such as NH4+, NO2-, Na+, K+, organic acids, and metals such as Al, Fe, and Ti. Source apportionment by chemical mass balance receptor modeling indicates that peat smoke can travel long distances and significantly affect the air quality at locations downwind.

  13. Overview of receptor-based source apportionment studies for speciated atmospheric mercury

    Directory of Open Access Journals (Sweden)

    I. Cheng

    2015-02-01

    Full Text Available Receptor-based source apportionment studies of speciated atmospheric mercury are not only concerned with source contributions, but also the influence of transport, transformation, and deposition processes on speciated atmospheric mercury concentrations at receptor locations. Previous studies applied multivariate receptor models including Principal Components Analysis and Positive Matrix Factorization, and back trajectory receptor models including Potential Source Contribution Function, Gridded Frequency Distributions, and Concentration-back trajectory models. Anthropogenic combustion sources, crustal/soil dust, and chemical and physical processes, such as gaseous elemental mercury (GEM oxidation reactions, boundary layer mixing, and GEM flux from surfaces, were inferred from the multivariate studies, which were predominantly conducted at receptor sites in Canada and the US. Back trajectory receptor models revealed potential impacts of large industrial areas such as the Ohio River Valley in the US and throughout China, metal smelters, mercury evasion from the ocean and Great Lakes, and free troposphere transport on receptor measurements. Input data and model parameters specific to atmospheric mercury receptor models are summarized and model strengths and weaknesses are also discussed. One area of improvement that applies to all receptor models is the greater focus on evaluating the accuracy of receptor models at identifying potential speciated atmospheric mercury sources, source locations, and chemical and physical processes in the atmosphere.

  14. Characterization and source apportionment of water pollution in Jinjiang River, China.

    Science.gov (United States)

    Chen, Haiyang; Teng, Yanguo; Yue, Weifeng; Song, Liuting

    2013-11-01

    Characterizing water quality and identifying potential pollution sources could greatly improve our knowledge about human impacts on the river ecosystem. In this study, fuzzy comprehensive assessment (FCA), pollution index (PI), principal component analysis (PCA), and absolute principal component score-multiple linear regression (APCS-MLR) were combined to obtain a deeper understanding of temporal-spatial characterization and sources of water pollution with a case study of the Jinjiang River, China. Measurement data were obtained with 17 water quality variables from 20 sampling sites in the December 2010 (withered water period) and June 2011 (high flow period). FCA and PI were used to comprehensively estimate the water quality variables and compare temporal-spatial variations, respectively. Rotated PCA and receptor model (APCS-MLR) revealed potential pollution sources and their corresponding contributions. Application results showed that comprehensive application of various multivariate methods were effective for water quality assessment and management. In the withered water period, most sampling sites were assessed as low or moderate pollution with characteristics pollutants of permanganate index and total nitrogen (TN), whereas 90% sites were classified as high pollution in the high flow period with higher TN and total phosphorus. Agricultural non-point sources, industrial wastewater discharge, and domestic sewage were identified as major pollution sources. Apportionment results revealed that most variables were complicatedly influenced by industrial wastewater discharge and agricultural activities in withered water period and primarily dominated by agricultural runoff in high flow period. PMID:23737126

  15. Spatial and temporal changes in apportionments by using sediment fingerprinting in a Spanish Pyrenean river catchment.

    Science.gov (United States)

    Palazón, Leticia; Latorre, Borja; Gaspar, Leticia; Navas, Ana

    2016-04-01

    The Barasona reservoir has suffered from siltation since its construction, with the loss of over one third of its storage volume in around 30 years (period 1972-1996). Information on sediment contribution and transport dynamics from the contributing catchment to the reservoir is needed to develop management plans for maintaining reservoir sustainability. Large variability in sediment delivery was found in previous studies in the Barasona catchment (1509 km2, Central Spanish Pyrenees) and the major sediment sources identified included badlands developed in the middle part of the catchment and the agricultural fields in its lower part. In this study the soils in the southern part of the catchment are main source of sediments (> 50%) for the southern tributaries. Differences in source apportionments between the two time-spanning reservoir samples reveal that agricultural fields contributed more in the 90s. Study fine sediment characteristics and their contributions in river catchments provide unique and diverse information to address catchment management problems, improving the spatial and temporal knowledge of land use sediment source contributions along the catchment to the reservoir infill.

  16. Error apportionment for atmospheric chemistry-transport models - a new approach to model evaluation

    Science.gov (United States)

    Solazzo, Efisio; Galmarini, Stefano

    2016-05-01

    In this study, methods are proposed to diagnose the causes of errors in air quality (AQ) modelling systems. We investigate the deviation between modelled and observed time series of surface ozone through a revised formulation for breaking down the mean square error (MSE) into bias, variance and the minimum achievable MSE (mMSE). The bias measures the accuracy and implies the existence of systematic errors and poor representation of data complexity, the variance measures the precision and provides an estimate of the variability of the modelling results in relation to the observed data, and the mMSE reflects unsystematic errors and provides a measure of the associativity between the modelled and the observed fields through the correlation coefficient. Each of the error components is analysed independently and apportioned to resolved processes based on the corresponding timescale (long scale, synoptic, diurnal, and intra-day) and as a function of model complexity.The apportionment of the error is applied to the AQMEII (Air Quality Model Evaluation International Initiative) group of models, which embrace the majority of regional AQ modelling systems currently used in Europe and North America.The proposed technique has proven to be a compact estimator of the operational metrics commonly used for model evaluation (bias, variance, and correlation coefficient), and has the further benefit of apportioning the error to the originating timescale, thus allowing for a clearer diagnosis of the processes that caused the error.

  17. Measurement and apportionment of radon source terms for modeling indoor environments

    Energy Technology Data Exchange (ETDEWEB)

    Harley, N.H.

    1992-01-01

    During the present 2 1/2 year contract period, we have made significant Progress in modeling the source apportionment of indoor [sup 222]Rn and in [sup 222]Rn decay product dosimetry. Two additional areas were worked on which we believe are useful for the DOE Radon research Program. One involved an analysis of the research house data, grouping the hourly house [sup 222]Rn measurements into 2 day, 7 day and 90 day intervals to simulate the response of passive monitors. Another area requiring some attention resulted in a publication of 3 years of our indoor/outdoor measurements in a high-rise apartment. Little interest has been evinced in apartment measurements yet 20% of the US population lives in multiple-family dwellings, not in contact with the ground. These data together with a summary of all other published data on apartments showed that apartments have only about 50% greater [sup 222]Rn concentration than the measured outdoor [sup 222]Rn. Apartment dwellers generally represent a low risk group regarding [sup 222]Rn exposure. The following sections describe the main projects in some detail.

  18. Measurement and apportionment of radon source terms for modeling indoor environments

    International Nuclear Information System (INIS)

    During the present 2 1/2 year contract period, we have made significant Progress in modeling the source apportionment of indoor 222Rn and in 222Rn decay product dosimetry. Two additional areas were worked on which we believe are useful for the DOE Radon research Program. One involved an analysis of the research house data, grouping the hourly house 222Rn measurements into 2 day, 7 day and 90 day intervals to simulate the response of passive monitors. Another area requiring some attention resulted in a publication of 3 years of our indoor/outdoor measurements in a high-rise apartment. Little interest has been evinced in apartment measurements yet 20% of the US population lives in multiple-family dwellings, not in contact with the ground. These data together with a summary of all other published data on apartments showed that apartments have only about 50% greater 222Rn concentration than the measured outdoor 222Rn. Apartment dwellers generally represent a low risk group regarding 222Rn exposure. The following sections describe the main projects in some detail

  19. Source apportionment of fluorine pollution in regional shallow groundwater at You'xi County southeast China.

    Science.gov (United States)

    Lü, Jian; Qiu, Haiyuan; Lin, Huangbin; Yuan, Yuan; Chen, Zhi; Zhao, Rurong

    2016-09-01

    Source apportionment of fluorine pollution in the regional shallow groundwater at You'xi County, southeast China, has been analyzed by means of monitoring F(-) ion change characteristics in this area. Meanwhile, pollution sources and influencing factors of the shallow groundwater have been uncovered by studying the correlation between F(-) and other related ions such as Na(+), Ca(2+), Cl(-), NO3(-), HCO3(-), as well as (K(+) + Na(+))/Ca(2+) ratio (R) and pH effect. The results show that F(-) ions in shallow groundwater at the study area come mainly from the dissolution of fluorinated minerals in a form of fluorite (CaF2), the so-called water-rock interaction, and there is a higher possibility for the occurrence of fluorine water where the ratio of (K(+) + Na(+))/Ca(2+) exceeds a value of 2.1. Moreover, the release and migration of F(-) ions have been favored by the alkaline environment in this study area. PMID:27239970

  20. Levels and source apportionment of volatile organic compounds in southwestern area of Mexico City

    Energy Technology Data Exchange (ETDEWEB)

    Rodolfo Sosa, E. [Centro de Ciencias de la Atmosfera, Universidad Nacional Autonoma de Mexico, Circuito Exterior, Ciudad Universitaria, C.P. 04510, D.F. (Mexico); Humberto Bravo, A. [Centro de Ciencias de la Atmosfera, Universidad Nacional Autonoma de Mexico, Circuito Exterior, Ciudad Universitaria, C.P. 04510, D.F. (Mexico)], E-mail: hbravo@servidor.unam.mx; Violeta Mugica, A. [Universidad Autonoma Metropolitana, Azcapotzalco, D.F. (Mexico); Pablo Sanchez, A. [Centro de Ciencias de la Atmosfera, Universidad Nacional Autonoma de Mexico, Circuito Exterior, Ciudad Universitaria, C.P. 04510, D.F. (Mexico); Emma Bueno, L. [Centro Nacional de Investigacion y Capacitacion Ambiental, Instituto Nacional de Ecologia (Mexico); Krupa, Sagar [Department of Plant Pathology, University of Minnesota, St. Paul, MN 55108 (United States)

    2009-03-15

    Thirteen volatile organic compounds (VOCs) were quantified at three sites in southwestern Mexico City from July 2000 to February 2001. High concentrations of different VOCs were found at a Gasoline refueling station (GS), a Condominium area (CA), and at University Center for Atmospheric Sciences (CAS). The most abundant VOCs at CA and CAS were propane, n-butane, toluene, acetylene and pentane. In comparison, at GS the most abundant were toluene, pentane, propane, n-butane, and acetylene. Benzene, a known carcinogenic compound had average levels of 28, 35 and 250 ppbC at CAS, CA, and GS respectively. The main contributing sources of the measured VOCs at CA and CAS were the handling and management of LP (Liquid Propane) gas, vehicle exhaust, asphalt works, and use of solvents. At GS almost all of the VOCs came from vehicle exhaust and fuel evaporation, although components of LP gas were also present. Based on the overall results possible abatement strategies are discussed. - Volatile organic compounds were quantified in order to perform their source apportionment in southwestern area of Mexico City.

  1. Source apportionment of carbonaceous aerosol in Sao Paulo using 13C and 14C measurements

    Science.gov (United States)

    Oyama, Beatriz; Andrade, Maria de Fatima; Holzinger, Rupert; Röckmann, Thomas; Meijer, Harro A. J.; Dusek, Ulrike

    2016-04-01

    The Metropolitan Area of Sao Paulo is affected by high aerosol concentrations, which contain a large fraction of organic material. Up to date, not much is known about the composition and origin of the organic aerosol in this city. We present the first source apportionment of the carbonaceous aerosol fraction in Sao Paulo, using stable (13C) and radioactive carbon isotopes (14C). 14C provides a clear-cut distinction between fossil sources, which contain no 14C, and contemporary sources such as biofuels, biomass burning, or biogenic sources, which contain a typical contemporary 14C/12C ratio. 13C can be used to distinguish C3 plants, such as maize and sugarcane, from C4 plants. This can help to identify a possible impact of sugarcane field burning in the rural areas of Sao Paulo State on the aerosol carbon in the city. In the first part of the study, we compare two tunnel studies: Tunnel 1 is frequented only by light duty vehicles, which run mainly on mixtures of gasoline with ethanol (gasohol, 25% ethanol and 85% gasoline) or hydrated ethanol (5% water and 95% ethanol). Tunnel 2 contains a significant fraction of heavy-duty diesel vehicles, and therefore the fraction of biofuels in the average fleet is lower. Comparison of 14C in organic and elemental carbon (OC and EC) shows that in both tunnels there is no significant contribution of biofuels to EC. Combusting ethanol-gasoline fuels in a vehicle engine does apparently not result in significant EC formation from ethanol. Biofuels contribute around 45% to OC in Tunnel 1 an only 20% in Tunnel 2, reflecting a strong impact of diesel vehicles in Tunnel 2. In the second part of the study we conduct a source apportionment of ambient aerosol carbon collected in a field study during winter (July-August) 2012. Ambient EC has two main sources, vehicular emissions and biomass burning. We estimate a contribution of vehicular sources to EC of roughly 90% during weekdays and 80% during weekends, using the 14C values measured in

  2. Paradigm for Distributive & Procedural Justice in Equitable Apportionment of Transboundary Ganges Waters Under Changing Climate & Landuse

    Science.gov (United States)

    Tyagi, H.; Gosain, A. K.; Khosa, R.; Anand, J.

    2015-12-01

    Rivers have no regard for human demarcated boundaries. Besides, ever increasing demand-supply gap & vested riparian interests, fuel transboundary water conflicts. For resolving such disputes, appropriation doctrines advocating equity & fairness have received endorsement in the Helsinki Rules-1966 & UN Convention-1997. Thus, current study proposes the principle of equitable apportionment for sharing Ganges waters as it balances the interests & deservedness of all stakeholders, namely, India & its 11 states, Bangladesh, Nepal, & China. The study endeavors to derive a reasonable share of each co-basin state by operationalizing the vague concepts of fairness & equity through an objective & quantitative framework encompassing proportionality & egalitarianism for distributive & procedural justice. Equal weightage factors reflecting hydrology, geography & water use potential are chosen for fair share computation, wherein each contender ranks these factors to maximize his entitlement. If cumulative claims exceed the water availability, each claimant puts forth next ranked factor & this process continues till the claims match availability. Due to inter-annual variability in few factors, scenarios for Rabi & Kharif seasons are considered apart from cases for maximum, upper quartile, median, lower quartile & minimum. Possibility of spatial homogeneity & heterogeneity in factors is also recognized. Sometimes lack of technical information hinders transboundary dispute resolution via legal mechanisms. Hence, the study also attempts to bridge this gap between law & technology through GIS-based SWAT hydrologic model by estimating the Ganges water yield, & consequent share of each riparian for range of flows incorporating e-flows as well, under present & future climate & landuse scenarios. 82% of India's territory lies within interstate rivers, & therefore this research is very pertinent as it can facilitate the decision makers in effective interstate water conflict resolution.

  3. Source apportionment of organic aerosol across Houston, TX during DISCOVER-AQ

    Science.gov (United States)

    Yoon, S.; Clark, A. E.; Ortiz, S. M.; Usenko, S.; Sheesley, R. J.

    2015-12-01

    As part of the ground-based sampling efforts during DISCOVER-AQ's Houston month-long campaign in September 2013, atmospheric particulate matter (PM) samples were collected at four sites: Moody Tower (urban), Manvel Croix (southern suburb), Conroe (northern suburb), and La Porte (urban industrial). The Houston metropolitan area, especially the Houston Ship Channel, is a densely industrialized urban city with large concentrations of petroleum refining, petrochemical manufacturing, and heavy traffic during peak hours. Due to these and other emission sources, the area is heavily impacted by ambient PM. This study will be looking at fine PM (diameter less than 2.5µm, PM2.5) from all four sites. PM2.5fraction is relevant for understanding fate and transport of organic contaminants and is widely known to negatively impact human health. Chemical analysis including radiocarbon (14C) and organic tracer measurements (polycyclic aromatic hydrocarbons, alkanes, hopanes, steranes, and levoglucosan) were used for source apportionment. The 14C measurements constrained CMB results to estimate both primary and secondary contributions to total organic carbon (TOC). Results indicate that Moody Tower had consistent primary motor vehicle exhaust contribution (18-27%) and a fossil secondary organic aerosol (SOA) contribution from 5-33% depending on atmospheric conditions. Conroe had a lower contribution of motor vehicle exhaust (5-10%) and similarly variable fraction of fossil SOA (4-25%). Manvel Croix had an interim motor vehicle contribution (9-15%) with a variable fossil SOA (5-30%). For contemporary OC, there was minimal contribution of wood smoke during examined weeks (0-9%) but larger contributor of biogenic SOA ranging from 40-75% at Moody Tower, 56-81% at Manvel Croix and 60-79% at Conroe. Overall, the motor vehicle contribution was consistent at each site during the analysis week, biogenic SOA was consistently high, while fossil SOA showed the most variability.

  4. Successful application of lead isotopes in source apportionment, legal proceedings, remediation and monitoring

    International Nuclear Information System (INIS)

    In late 2006, the seaside community in Esperance Western Australia was alerted to thousands of native bird species dying. The source of the lead (Pb) was determined by Pb isotopes to derive from the handling of Pb carbonate concentrate through the Port, which began in July 2005. Concern was expressed for the impact of this on the community. Our objectives were to employ Pb isotope ratios to evaluate the source of Pb in environmental samples for use in legal proceedings, and for use in remediation and monitoring. Isotope measurements were undertaken of bird livers, plants, drinking water, soil, harbour sediments, air, bulk ceiling dust, gutter sludge, surface swabs and blood. The unique lead isotopic signature of the contaminating Pb carbonate enabled diagnostic apportionment of lead in samples. Apart from some soil and water samples, the proportion of contaminating Pb was >95% in the environmental samples. Lead isotopes were critical in resolving legal proceedings, are being used in the remediation of premises, were used in monitoring of workers involved in the decontamination of the storage facility, and monitoring transport of the concentrate through another port facility. Air samples show the continued presence of contaminant Pb, more than one year after shipping of concentrate ceased, probably arising from dust resuspension. Brief details of the comprehensive testing and cleanup of the Esperance community are provided along with the role of the Community. Lead isotopic analyses can provide significant benefits to regulatory agencies, interested parties, and the community where the signature is able to be characterised with a high degree of certainty. - Highlights: ▶ Lead carbonate concentrate. ▶ Successful use of Pb isotopes in identifying sources of Pb arising from transport and shipping. ▶ Use of Pb isotopes in legal proceedings and their use in cleanup of residences. ▶ Use of Pb isotopes in cleanup of a residual 9000 tonnes of Pb carbonate and in

  5. Source apportionment of atmospheric particulate carbon in Las Vegas, Nevada,USA

    Institute of Scientific and Technical Information of China (English)

    Mark C.Green; Judith C.Chow; M.-C.Oliver Chang; L.-W.Antony Chen; Hampden D.Kuhns; Vicken R.Etyemezian; John G.Watson

    2013-01-01

    A study was conducted to quantify wintertime contributions of source types to carbonaceous PM2.5 at four urban sites in the Las Vegas Valley,one of the most rapidly growing urban areas in the southwestern United States.Twenty-four hour average ambient samples were collected for mass,ions,elements,organic carbon (OC),elemental carbon (EC),and trace organic markers analysis.Additional measurements were made to determine diurnal patterns in light-absorbing black carbon (BC) as a marker for combustion sources.Carbonaceous PM sources of on-road gasoline vehicles,on-road diesel vehicles,and off-road diesel engines were characterized with their chemical profiles,as well as fuel-based emission factors,using an In-Plume Sampling System.The Effective Variance Chemical Mass Balance (EV-CMB) source apportionment model was applied to the ambient samples collected,using source profiles developed in this study as well as profiles from other relevant studies.Four main sources contributed to PM2.5 carbon within the Las Vegas Valley:(1) paved road dust,(2) on-road gasoline vehicles,(3) residential wood combustion,and (4) on-road diesel vehicles.CMB estimated that on-road mixed fleet gasoline vehicles are the largest source for OC and EC at all the sites.The contribution of paved road dust to both OC and EC was 5-10% at the four sites.On-road diesel vehicles contribute 22% of the OC and 34% of the EC at a site near the city center,which is located immediately downwind of a major freeway.Residential wood combustion is a more important source than on-road diesel vehicles for two residential neighborhood sites.These results are consistent with our conceptual model,and the research methodology may be applied to studying other urban areas.

  6. Source apportionment of PM2.5 carbonaceous aerosol in Baghdad, Iraq

    Science.gov (United States)

    Hamad, Samera Hussein; Schauer, James Jay; Heo, Jongbae; Kadhim, Ahmed K. H.

    2015-04-01

    Baghdad is the second largest city in the Middle East and suffers from severe air quality degradation due to the high levels of the atmospheric particulate matter (PM). Limited information exists regarding the sources of PM in Baghdad, and the lack of information on sources inhibits the development of control strategies to reduce air pollution. To better understand the nature of fine particulate matter (PM2.5) in Baghdad and the Middle East, a one year sampling campaign to collect PM2.5 was conducted from September 2012 through September 2013, missing August 2013 samples due to the security situation. 24-hour integrated samples collected on a 1-in-6 day schedule were analyzed for the major components, and monthly average samples were analyzed by gas chromatography mass spectrometry (GCMS) methods to measure particle-phase organic molecular markers. The results of organic molecular markers were used in a chemical mass balance (CMB) model to quantify the sources of PM2.5 organic carbon (OC) and PM2.5 mass. Primary sources accounted for 44% of the measured PM2.5, and secondary sources were estimated to make up 28% of the measured PM2.5. Picene, a tracer of coal combustion detected in Baghdad where there is no evidence for coal combustion, can be attributed to burning crude oil and other low quality fuels in Baghdad. Source apportionment results showed that the dominant sources of the carbonaceous aerosols in Baghdad are gasoline (37 ± 6%) and diesel engines (17 ± 3%) which can be attributed to the extensive use of gasoline and diesel powered generators in Baghdad. Wood burning and residual oil combustion contributed to 5 ± 0.4 and 1 ± 0.2% respectively of OC. The unresolved sources contributed to 42 ± 19% of the OC which represented the secondary organic aerosol (SOA) and the unidentified sources.

  7. Aerosol source apportionment from 1-year measurements at the CESAR tower in Cabauw, the Netherlands

    Science.gov (United States)

    Schlag, Patrick; Kiendler-Scharr, Astrid; Blom, Marcus Johannes; Canonaco, Francesco; Sebastiaan Henzing, Jeroen; Moerman, Marcel; Prévôt, André Stephan Henry; Holzinger, Rupert

    2016-07-01

    Intensive measurements of submicron aerosol particles and their chemical composition were performed with an Aerosol Chemical Speciation Monitor (ACSM) at the Cabauw Experimental Site for Atmospheric Research (CESAR) in Cabauw, the Netherlands, sampling at 5 m height above ground. The campaign lasted nearly 1 year from July 2012 to June 2013 as part of the EU-FP7-ACTRIS project (Q-ACSM Network). Including equivalent black carbon an average particulate mass concentration of 9.50 µg m-3 was obtained during the whole campaign with dominant contributions from ammonium nitrate (45 %), organic aerosol (OA, 29 %), and ammonium sulfate (19 %). There were 12 exceedances of the World Health Organization (WHO) PM2.5 daily mean limit (25 µg m-3) observed at this rural site using PM1 instrumentation only. Ammonium nitrate and OA represented the largest contributors to total particulate matter during periods of exceedance. Source apportionment of OA was performed season-wise by positive matrix factorization (PMF) using the multilinear engine 2 (ME-2) controlled via the source finder (SoFi). Primary organic aerosols were attributed mainly to traffic (8-16 % contribution to total OA, averaged season-wise) and biomass burning (0-23 %). Secondary organic aerosols (SOAs, 61-84 %) dominated the organic fraction during the whole campaign, particularly on days with high mass loadings. A SOA factor which is attributed to humic-like substances (HULIS) was identified as a highly oxidized background aerosol in Cabauw. This shows the importance of atmospheric aging processes for aerosol concentration at this rural site. Due to the large secondary fraction, the reduction of particulate mass at this rural site is challenging on a local scale.

  8. Biomass burning in the Amazon region: Aerosol source apportionment and associated health risk assessment

    Science.gov (United States)

    de Oliveira Alves, Nilmara; Brito, Joel; Caumo, Sofia; Arana, Andrea; de Souza Hacon, Sandra; Artaxo, Paulo; Hillamo, Risto; Teinilä, Kimmo; Batistuzzo de Medeiros, Silvia Regina; de Castro Vasconcellos, Pérola

    2015-11-01

    The Brazilian Amazon represents about 40% of the world's remaining tropical rainforest. However, human activities have become important drivers of disturbance in that region. The majority of forest fire hotspots in the Amazon arc due to deforestation are impacting the health of the local population of over 10 million inhabitants. In this study we characterize western Amazonia biomass burning emissions through the quantification of 14 Polycyclic Aromatic Hydrocarbons (PAHs), Organic Carbon, Elemental Carbon and unique tracers of biomass burning such as levoglucosan. From the PAHs dataset a toxic equivalence factor is calculated estimating the carcinogenic and mutagenic potential of biomass burning emissions during the studied period. Peak concentration of PM10 during the dry seasons was observed to reach 60 μg m-3 on the 24 h average. Conversely, PM10 was relatively constant throughout the wet season indicating an overall stable balance between aerosol sources and sinks within the filter sampling resolution. Similar behavior is identified for OC and EC components. Levoglucosan was found in significant concentrations (up to 4 μg m-3) during the dry season. Correspondingly, the estimated lung cancer risk calculated during the dry seasons largely exceeded the WHO health-based guideline. A source apportionment study was carried out through the use of Absolute Principal Factor Analysis (APFA), identifying a three-factor solution. The biomass burning factor is found to be the dominating aerosol source, having 75.4% of PM10 loading. The second factor depicts an important contribution of several PAHs without a single source class and therefore was considered as mixed sources factor, contributing to 6.3% of PM10. The third factor was mainly associated with fossil fuel combustion emissions, contributing to 18.4% of PM10. This work enhances the knowledge of aerosol sources and its impact on climate variability and local population, on a site representative of the

  9. Application of hierarchical Bayesian unmixing models in river sediment source apportionment

    Science.gov (United States)

    Blake, Will; Smith, Hugh; Navas, Ana; Bodé, Samuel; Goddard, Rupert; Zou Kuzyk, Zou; Lennard, Amy; Lobb, David; Owens, Phil; Palazon, Leticia; Petticrew, Ellen; Gaspar, Leticia; Stock, Brian; Boeckx, Pacsal; Semmens, Brice

    2016-04-01

    Fingerprinting and unmixing concepts are used widely across environmental disciplines for forensic evaluation of pollutant sources. In aquatic and marine systems, this includes tracking the source of organic and inorganic pollutants in water and linking problem sediment to soil erosion and land use sources. It is, however, the particular complexity of ecological systems that has driven creation of the most sophisticated mixing models, primarily to (i) evaluate diet composition in complex ecological food webs, (ii) inform population structure and (iii) explore animal movement. In the context of the new hierarchical Bayesian unmixing model, MIXSIAR, developed to characterise intra-population niche variation in ecological systems, we evaluate the linkage between ecological 'prey' and 'consumer' concepts and river basin sediment 'source' and sediment 'mixtures' to exemplify the value of ecological modelling tools to river basin science. Recent studies have outlined advantages presented by Bayesian unmixing approaches in handling complex source and mixture datasets while dealing appropriately with uncertainty in parameter probability distributions. MixSIAR is unique in that it allows individual fixed and random effects associated with mixture hierarchy, i.e. factors that might exert an influence on model outcome for mixture groups, to be explored within the source-receptor framework. This offers new and powerful ways of interpreting river basin apportionment data. In this contribution, key components of the model are evaluated in the context of common experimental designs for sediment fingerprinting studies namely simple, nested and distributed catchment sampling programmes. Illustrative examples using geochemical and compound specific stable isotope datasets are presented and used to discuss best practice with specific attention to (1) the tracer selection process, (2) incorporation of fixed effects relating to sample timeframe and sediment type in the modelling

  10. Source apportionment of surface ozone in the Yangtze River Delta, China in the summer of 2013

    Science.gov (United States)

    Li, L.; An, J. Y.; Shi, Y. Y.; Zhou, M.; Yan, R. S.; Huang, C.; Wang, H. L.; Lou, S. R.; Wang, Q.; Lu, Q.; Wu, J.

    2016-11-01

    We applied ozone source apportionment technology (OSAT) with tagged tracers coupled within the Comprehensive Air Quality Model with Extensions (CAMx) to study the region and source category contribution to surface ozone in the Yangtze River Delta area in summer of 2013. Results indicate that the daytime ozone concentrations in the YRD region are influenced by emissions both locally, regionally and super-regionally. At urban Shanghai, Hangzhou and Suzhou receptors, the ozone formation is mainly VOC-limited, precursor emissions form Zhejiang province dominate their O3 concentrations. At the junction area among two provinces and Shanghai city, the ozone is usually influenced by all the three areas. The daily max O3 at the Dianshan Lake in July are contributed by Zhejiang (48.5%), Jiangsu (11.7%), Anhui (11.6%) and Shanghai (7.4%), long-range transport constitutes around 20.9%. At Chongming site, the BVOC emissions rate is higher than urban region. Regional contribution results show that Shanghai constitutes 15.6%, Jiangsu contributes 16.2% and Zhejiang accounts for 25.5% of the daily max O3. The analysis of the source category contribution to high ozone in the Yangtze River Delta region indicates that the most significant anthropogenic emission source sectors contributing to O3 pollution include industry, vehicle exhaust, although the effects vary with source sector and selected pollution episodes. Emissions of NOx and VOCs emitted from the fuel combustion of industrial boilers and kilns, together with VOCs emissions from industrial process contribute a lot to the high concentrations in urban Hangzhou, Suzhou and Shanghai. The contribution from regional elevated power plants cannot be neglected, especially to Dianshan Lake. Fugitive emissions of volatile pollution sources also have certain contribution to regional O3. These results indicate that the regional collaboration is of most importance to reduce ambient ozone pollution, particularly during high ozone episodes.

  11. Source apportionment of elevated wintertime PAHs by compound-specific radiocarbon analysis

    Science.gov (United States)

    Sheesley, R. J.; Kruså, M.; Krecl, P.; Johansson, C.; Gustafsson, Ã.-.

    2008-12-01

    Natural abundance radiocarbon analysis facilitates distinct source apportionment between contemporary biomass/biofuel (14C "alive") versus fossil fuel (14C "dead") combustion. Here, the first compound-specific radiocarbon analysis (CSRA) of atmospheric polycylic aromatic hydrocarbons (PAHs) was demonstrated for a set of samples collected in Lycksele, Sweden a small town with frequent episodes of severe atmospheric pollution in the winter. Renewed interest in residential wood combustion means than this type of seasonal pollution is of increasing concern in many areas. Five individual/paired PAH isolates from three pooled fortnight-long filter collections were analyzed by CSRA: phenanthrene, fluoranthene, pyrene, benzo[b+k]fluoranthene and indeno[cd]pyrene plus benzo[ghi]perylene; phenanthrene was the only compound also analyzed in the gas phase. The measured Δ14C for PAHs spanned from -138.3‰ to 58.0‰. A simple isotopic mass balance model was applied to estimate the fraction biomass (fbiomass) contribution that was constrained to a range of 71% for indeno[cd]pyrene+benzo[ghi]perylene to 87% for the gas phase phenanthrene and particulate fluoranthene, respectively. Indeno[cd]pyrene plus benzo[ghi]perylene, known to be enhanced in gasoline-powered motor vehicle exhaust compared to diesel exhaust, had the lowest contribution of biomass combustion of the measured PAHs by 9%. The total organic carbon (TOC, defined as carbon remaining after removal of inorganic carbon) fbiomass was estimated to be 77%, which falls within the range for PAHs. This CSRA data of atmospheric PAHs demonstrate the non-uniformity of biomass combustion contribution to different PAHs even in a location with limited local emission sources and illustrates that regulatory efforts would not evenly reduce all PAHs.

  12. A Regional Assessment of Marine Vessel PM2.5 Impacts in the U.S. Pacific Northwest Using a Receptor Based Source Apportionment Method

    Science.gov (United States)

    This work reports the results of a regional receptor-based source apportionment analysis using the Positive Matrix Factorization (PMF) model on chemically speciated PM2.5 data from 36 urban and rural monitoring sites within the U.S. Pacific Northwest. The approach taken is to mo...

  13. The Apportionment of Liability for Damages between Employer and Union in Section 301 Actions Involving a Union's Breach of Its Duty of Fair Representation.

    Science.gov (United States)

    Linsey, James L.

    1979-01-01

    Examines the meaning and application of the Supreme Court's ruling in "Vaca v Sipes" concerning the apportionment of liability between union and employers in duty of fair representation cases. Available from the Managing Editor, Mercer Law Review, Mercer University, 1400 Coleman Avenue, Macon, Georgia 31207; single lead article issue $3.50.…

  14. Source apportionment of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) in ambient air of an industrial region in Turkey

    Science.gov (United States)

    Aydin, Yagmur Meltem; Kara, Melik; Dumanoglu, Yetkin; Odabasi, Mustafa; Elbir, Tolga

    2014-11-01

    Source apportionment is generally applied to a time series of data collected at a single site. However, in a complex airshed containing several different sources, it may be helpful to collect samples from multiple sites to ensure that some of them have low contributions from specific sources, thus the boundaries can be properly defined. Ambient air polycyclic aromatic hydrocarbon (PAH) and polychlorinated biphenyls (PCB) samples (n = 160) were collected at 40 sites during four seasons (summer, fall, winter, and spring) between July 2009 and April 2010 in the heavily industrialized Aliaga region in Turkey to investigate their spatial, seasonal variations and to identify possible PAH and PCB sources. The newest version of EPA PMF (V5.0) having the capability of handling multiple site data was used for source apportionment. Five PAH sources were identified as biomass and coal combustion, iron-steel production, unburned crude oil and petroleum products, and diesel and gasoline exhaust emissions with contributions of 40, 27, 27, 3, and 3%, respectively. The sources of PCBs were identified as iron-steel production (consisting of steel-making and ship breaking activities), coal and wood combustion, and evaporative emissions from technical PCB mixtures with contributions of 57, 31, and 12%, respectively.

  15. Source apportionment profile of the fine air particulate pollution in a sampling site in Quezon City (Philippines)

    International Nuclear Information System (INIS)

    Air particulate matter (PM10) was monitored and collected at a sampling site in Quezon City, Philippines since 1998 for the purpose of source identification and source apportionment. For such to be achieved, parameters like particulate mass, black carbon, and elemental concentration and identification must be determined. These were attained by using gravimetry, reflectometr, and particle-induced x-ray emissions (PIXE) spectrometry and x-ray fluorescence spectrometry (XRF), respectively. Source apportionment was attained with the use of Positive Matrix Factorization 2 (PMF2). This resulted to the identification of six air pollution sources. These are vehicular emissions (49%), smoke (14%), secondary S (22%), fine soil (8%) and industry (7%). Data also showed PM10 compliance to the Philippines 1-year guideline value of 60μg m-3 but in excedance of the WHO 1-year guideline value of 20μg m-3. Furthermore, PM2.5 levels are in exceedance of the WHO 1-year guideline value of 15μg m-3 and the WHO 1-year guideline value of 10μg m-3. Also worth noting, particulate lead (Pb) levels of the fine fractions observed to follow a decreasing pattern that coincides well with the introduction of unleaded-gasoline in 1998, and the eventual phase-out of the leaded-gasoline in 2001.(author)

  16. Multimedia fate and source apportionment of polycyclic aromatic hydrocarbons in a coking industry city in Northern China

    International Nuclear Information System (INIS)

    A steady state Level III fate model was established and applied to quantify source–receptor relationship in a coking industry city in Northern China. The local emission inventory of PAHs, as the model input, was acquired based on energy consumption and emission factors. The model estimations were validated by measured data and indicated remarkable variations in the paired isomeric ratios. When a rectification factor, based on the receptor-to-source ratio, was calculated by the fate model, the quantitatively verified molecular diagnostic ratios provided reasonable results of local PAH emission sources. Due to the local ban and measures on small scale coking activities implemented from the beginning of 2004, the model calculations indicated that the local emission amount of PAHs in 2009 decreased considerably compared to that in 2003. -- Highlights: •A steady-state fate model could well elucidate the multimedia fate of PAHs. •A rectification factor for correcting the paired isomeric ratio was calculated. •The corrected isomeric ratios were successfully applied to source apportionment. -- Based on multimedia model correction, the specific isomeric ratios could provide reasonable apportionments for the local PAHs emission sources

  17. Sediment PAH source apportionment in the Liaohe River using the ME2 approach: A comparison to the PMF model.

    Science.gov (United States)

    Xu, Jian; Peng, Xing; Guo, Chang-Sheng; Xu, Jiao; Lin, Hai-Xia; Shi, Guo-Liang; Lv, Jia-Pei; Zhang, Yuan; Feng, Yin-Chang; Tysklind, Mats

    2016-05-15

    Environmental contaminant source apportionment is essential for pollution management and control. This study analysed surface sediment samples for 16 priority polycyclic aromatic hydrocarbons (PAHs). PAH sources were identified by two receptor models, which included positive matrix factorization (PMF) and multilinear engine 2 (ME2). Three PAH sources in the Liaohe River sediments were identified by PMF, including traffic, coke oven and coal combustion. The ME2 model apportioned one additional source. The two models yielded excellent correlation coefficients between the measured and predicted PAH concentrations. Traffic emission was the primary PAH source associated with the Liaohe River sediments, with estimated PMF contributions of 58% in May and 63% in September. Coke oven (19%-25%) and coal combustion (13%-18%) were the other two major PAH sources. For ME2, gasoline and diesel were separated: accounted for 14% in May and 16% in September; and 53% in May and 48% in September. This study marks the first application of the ME2 model to study sediment contaminant source apportionment. The methodology can potentially be applied to other aquatic environment contaminants. PMID:26925728

  18. GIS-based source identification and apportionment of diffuse water pollution: perfluorinated compound pollution in the Tokyo Bay basin.

    Science.gov (United States)

    Zushi, Yasuyuki; Masunaga, Shigeki

    2011-11-01

    To efficiently reduce perfluorinated compound (PFC) pollution, it is important to have an understanding of PFC sources and their contribution to the pollution. In this study, source identification of diffuse water pollution by PFCs was conducted using a GIS-based approach. Major components of the source identification were collection of the monitoring data and preparation of the corresponding geographic information that was extracted from a constructed GIS database. The spatially distributed pollution factors were then explored by multiple linear regression analysis, after which they were visually expressed using GIS. Among the 35 PFC homologues measured in a survey of the Tokyo Bay basin, 18 homologues were analyzed. Pollution by perfluorooctane sulfonate (PFOS) was explained well by the percentage of arterial traffic area in the basin, and the 84% variance of the measured PFOS concentration was explained by two geographic variables, arterial traffic area and population. Source apportionment between point and nonpoint sources was conducted based on the results of the analysis. The contribution of PFOS from nonpoint sources was comparable to that from point sources in several major rivers flowing into Tokyo Bay. Source identification and apportionment using the GIS-based approach was shown to be effective, especially for ubiquitous types of pollution, such as PFC pollution. PMID:21885084

  19. Source apportionment of particulate matter in a South Asian Mega City: A case study of Karachi

    Science.gov (United States)

    Shahid, imran

    2016-04-01

    PM2.5 and PM10-2.5. In order to make air quality better and risk free in South Asian cities a comprehensive and integrated regional effort is required that include continuous air quality monitoring, source apportionment and implementation of regional air quality policies.

  20. Fine particulate matter in the tropical environment: monsoonal effects, source apportionment, and health risk assessment

    Science.gov (United States)

    Khan, M. F.; Latif, M. T.; Saw, W. H.; Amil, N.; Nadzir, M. S. M.; Sahani, M.; Tahir, N. M.; Chung, J. X.

    2016-01-01

    The health implications of PM2.5 in the tropical region of Southeast Asia (SEA) are significant as PM2.5 can pose serious health concerns. PM2.5 concentration and sources here are strongly influenced by changes in the monsoon regime from the south-west quadrant to the north-east quadrant in the region. In this work, PM2.5 samples were collected at a semi-urban area using a high-volume air sampler at different seasons on 24 h basis. Analysis of trace elements and water-soluble ions was performed using inductively coupled plasma mass spectroscopy (ICP-MS) and ion chromatography (IC), respectively. Apportionment analysis of PM2.5 was carried out using the United States Environmental Protection Agency (US EPA) positive matrix factorization (PMF) 5.0 and a mass closure model. We quantitatively characterized the health risks posed to human populations through the inhalation of selected heavy metals in PM2.5. 48 % of the samples collected exceeded the World Health Organization (WHO) 24 h PM2.5 guideline but only 19 % of the samples exceeded 24 h US EPA National Ambient Air Quality Standard (NAAQS). The PM2.5 concentration was slightly higher during the north-east monsoon compared to south-west monsoon. The main trace metals identified were As, Pb, Cd, Ni, Mn, V, and Cr while the main ions were SO42-, NO3-, NH4+, and Na. The mass closure model identified four major sources of PM2.5 that account for 55 % of total mass balance. The four sources are mineral matter (MIN) (35 %), secondary inorganic aerosol (SIA) (11 %), sea salt (SS) (7 %), and trace elements (TE) (2 %). PMF 5.0 elucidated five potential sources: motor vehicle emissions coupled with biomass burning (31 %) were the most dominant, followed by marine/sulfate aerosol (20 %), coal burning (19 %), nitrate aerosol (17 %), and mineral/road dust (13 %). The hazard quotient (HQ) for four selected metals (Pb, As, Cd, and Ni) in PM2.5 mass was highest in PM2.5 mass from the coal burning source and least in PM2.5 mass

  1. Seasonal variability and source apportionment of volatile organic compounds (VOCs) in the Paris megacity (France)

    Science.gov (United States)

    Baudic, Alexia; Gros, Valérie; Sauvage, Stéphane; Locoge, Nadine; Sanchez, Olivier; Sarda-Estève, Roland; Kalogridis, Cerise; Petit, Jean-Eudes; Bonnaire, Nicolas; Baisnée, Dominique; Favez, Olivier; Albinet, Alexandre; Sciare, Jean; Bonsang, Bernard

    2016-09-01

    Within the framework of air quality studies at the megacity scale, highly time-resolved volatile organic compound (C2-C8) measurements were performed in downtown Paris (urban background sites) from January to November 2010. This unique dataset included non-methane hydrocarbons (NMHCs) and aromatic/oxygenated species (OVOCs) measured by a GC-FID (gas chromatograph with a flame ionization detector) and a PTR-MS (proton transfer reaction - mass spectrometer), respectively. This study presents the seasonal variability of atmospheric VOCs being monitored in the French megacity and their various associated emission sources. Clear seasonal and diurnal patterns differed from one VOC to another as the result of their different origins and the influence of environmental parameters (solar radiation, temperature). Source apportionment (SA) was comprehensively conducted using a multivariate mathematical receptor modeling. The United States Environmental Protection Agency's positive matrix factorization tool (US EPA, PMF) was used to apportion and quantify ambient VOC concentrations into six different sources. The modeled source profiles were identified from near-field observations (measurements from three distinct emission sources: inside a highway tunnel, at a fireplace and from a domestic gas flue, hence with a specific focus on road traffic, wood-burning activities and natural gas emissions) and hydrocarbon profiles reported in the literature. The reconstructed VOC sources were cross validated using independent tracers such as inorganic gases (NO, NO2, CO), black carbon (BC) and meteorological data (temperature). The largest contributors to the predicted VOC concentrations were traffic-related activities (including motor vehicle exhaust, 15 % of the total mass on the annual average, and evaporative sources, 10 %), with the remaining emissions from natural gas and background (23 %), solvent use (20 %), wood-burning (18 %) and a biogenic source (15 %). An important finding of

  2. Concentration levels and source apportionment of ultrafine particles in road microenvironments

    Science.gov (United States)

    Argyropoulos, G.; Samara, C.; Voutsa, D.; Kouras, A.; Manoli, E.; Voliotis, A.; Tsakis, A.; Chasapidis, L.; Konstandopoulos, A.; Eleftheriadis, K.

    2016-03-01

    A mobile laboratory unit (MOBILAB) with on-board instrumentation (Scanning Mobility Particle Sizer, SMPS; Ambient NOx analyzer) was used to measure size-resolved particle number concentrations (PNCs) of quasi-ultrafine particles (UFPs, 9-372 nm), along with NOx, in road microenvironments. On-road measurements were carried out in and around a large Greek urban agglomeration, the Thessaloniki Metropolitan Area (TMA). Two 2-week measurement campaigns were conducted during the warm period of 2011 and the cold period of 2012. During each sampling campaign, MOBILAB was driven through a 5-day inner-city route and a second 5-day external route covering in total a wide range of districts (urban, urban background, industrial and residential), and road types (major and minor urban roads, freeways, arterial and interurban roads). All routes were conducted during working days, in morning and in afternoon hours under real-world traffic conditions. Spatial classification of MOBILAB measurements involved the assignment of measurement points to location bins defined by the aspect ratio of adjacent urban street canyons (USCs). Source apportionment was further carried out, by applying Positive Matrix Factorization (PMF) to particle size distribution data. Apportioned PMF factors were interpreted, by employing a two-step methodology, which involved (a) statistical association of PMF factor contributions with 12 h air-mass back-trajectories ending at the TMA during MOBILAB measurements, and (b) Multiple Linear Regression (MLR) using PMF factor contributions as the dependent variables, while relative humidity, solar radiation flux, and vehicle speed were used as the independent variables. The applied data analysis showed that low-speed cruise and high-load engine operation modes are the two dominant sources of UFPs in most of the road microenvironments in the TMA, with significant contributions from background photochemical processes during the warm period, explaining the reversed

  3. Seasonal effect and source apportionment of polycyclic aromatic hydrocarbons in PM2.5

    Science.gov (United States)

    Khan, Md Firoz; Latif, Mohd Talib; Lim, Chee Hou; Amil, Norhaniza; Jaafar, Shoffian Amin; Dominick, Doreena; Mohd Nadzir, Mohd Shahrul; Sahani, Mazrura; Tahir, Norhayati Mohd

    2015-04-01

    This study aims to investigate distribution and sources of 16 polycyclic aromatic hydrocarbons (PAHs) bound to fine particulate matter (PM2.5) captured in a semi-urban area in Malaysia during different seasons, and to assess their health risks. PM2.5 samples were collected using a high volume air sampler on quartz filter paper at a flow rate of 1 m3 min-1 for 24 h. PAHs on the filter paper were extracted with dichloromethane (DCM) using an ultrasonic centrifuge solid-phase extraction method and measured by gas chromatography-mass spectroscopy. The results showed that the range of PAHs concentrations in the study period was between 0.21 and 12.08 ng m-3. The concentrations of PAHs were higher during the south-west monsoon (0.21-12.08 ng m-3) compared to the north-east monsoon (0.68-3.80 ng m-3). The high molecular weight (HMW) PAHs (≥5 ring) are significantly prominent (>70%) compared to the low molecular weight (LMW) PAHs (≤4 ring) in PM2.5. The Spearman correlation indicates that the LMW and HMW PAHs correlate strongly among themselves. The diagnostic ratios (DRs) of I[c]P/I[c]P + BgP and B[a]P/B[g]P suggest that the HMW PAHs originated from fuel combustion sources. The source apportionment analysis of PAHs was resolved using DRs-positive matrix factorization (PMF)-multiple linear regression (MLR). The main sources identified were (a) gasoline combustion (65%), (b) diesel and heavy oil combustion (19%) and (c) natural gas and coal burning (15%). The health risk evaluation, by means of the lifetime lung cancer risk (LLCR), showed no potential carcinogenic risk from the airborne BaPeq (which represents total PAHs at the present study area in Malaysia). The seasonal LLCR showed that the carcinogenic risk of total PAHs were two fold higher during south-westerly monsoon compared to north-easterly monsoon.

  4. Overview of receptor-based source apportionment studies for speciated atmospheric mercury

    Science.gov (United States)

    Cheng, I.; Xu, X.; Zhang, L.

    2015-07-01

    Receptor-based source apportionment studies of speciated atmospheric mercury are not only concerned with source contributions but also with the influence of transport, transformation, and deposition processes on speciated atmospheric mercury concentrations at receptor locations. Previous studies applied multivariate receptor models including principal components analysis and positive matrix factorization, and back trajectory receptor models including potential source contribution function, gridded frequency distributions, and concentration-back trajectory models. Combustion sources (e.g., coal combustion, biomass burning, and vehicular, industrial and waste incineration emissions), crustal/soil dust, and chemical and physical processes, such as gaseous elemental mercury (GEM) oxidation reactions, boundary layer mixing, and GEM flux from surfaces were inferred from the multivariate studies, which were predominantly conducted at receptor sites in Canada and the US. Back trajectory receptor models revealed potential impacts of large industrial areas such as the Ohio River valley in the US and throughout China, metal smelters, mercury evasion from the ocean and the Great Lakes, and free troposphere transport on receptor measurements. Input data and model parameters specific to atmospheric mercury receptor models are summarized and model strengths and weaknesses are also discussed. Multivariate models are suitable for receptor locations with intensive air monitoring because they require long-term collocated and simultaneous measurements of speciated atmospheric Hg and ancillary pollutants. The multivariate models provide more insight about the types of Hg emission sources and Hg processes that could affect speciated atmospheric Hg at a receptor location, whereas back trajectory receptor models are mainly ideal for identifying potential regional Hg source locations impacting elevated Hg concentrations. Interpretation of the multivariate model output to sources can be

  5. Triple-Isotope-Based Source Apportionment of Methane in Waters of the Outer Laptev Sea

    Science.gov (United States)

    Steinbach, J.; Holmstrand, H.; Shcherbakova, K.; Kosmach, D.; Sapart, C. J.; Panova, E.; Bruchert, V.; Semiletov, I. P.; Shakhova, N. E.; Gustafsson, O.

    2015-12-01

    The East Siberian Arctic Shelf (ESAS) hosts large methane (CH4) deposits in the form of gas hydrates, gas pockets within subsea permafrost and in deeper reservoirs. For over a decade, annual expeditions have documented methane releases into the water column in large parts of this region. However, there is still insufficient knowledge of which pools are releasing the methane - one important piece of information required for a deeper understanding of the system and towards predicting future releases. A powerful tool for quantifying the relative contribution of releases from different sources is multi-dimensional isotope analysis of CH4 in the water column. Using the full triple isotope characterization (δ13C-CH4, δD-CH4, Δ14C-CH4) allows deconvolution of CH4 sources between thermogenic and biogenic origins and of different reservoir ages.During the SWERUS-C3 expedition in summer 2014 we investigated the distribution of dissolved methane and its isotope signatures in the water column along the outer ESAS and its adjacent slope and ridges. Over 1500 samples for CH4 concentration from high-resolution vertical profiles (up to 12 depths) were analyzed onboard; 900 samples were taken for stable isotopes analysis; and a total of 80 larger water samples were taken at selected locations for Δ14C-CH4 analysis. CH4 was extracted from these samples onboard using custom-built CH4-stripping systems and stored in absorbent traps for further processing and radiocarbon analysis onshore. One focus was to probe CH4 sources in seep areas, identified by a combination of geophysical features in the sediment, observation of bubbles in the water column and measured CH4 profiles. Here we present triple isotope data from inside and outside seep areas of the outer Laptev Sea and source-apportionment for this region. Dissolved methane concentration there reached up to 1400nM. Stable isotopes results in near bottom waters are rather enriched: Initial results show -142 to -133‰ vs SMOW for

  6. Aerosols characterisation and pollution source apportionment in Aboesi Airshed: impact assessment

    International Nuclear Information System (INIS)

    Atmospheric aerosols in the PM10- 2.5 (N = 155) and PM2.5 (N = 155) fractions have been sampled and characterised at Aboesi, in the Shama District of Ghana (about 10 meters above mean sea level) for 12 months during dry and rainy seasons. The samples have been analyzed by Energy Dispersive Polarised X-ray Fluorescence (EDPXRF). Particle Induced X-ray Emission (PIXE), and Particle Induced Gamma Emission (PIGE) in order to quantify their elemental constituents. Average annual concentrations of 88.4 µgm-3 (range: 6.8 - 590.1 µgm-3 ) and 25 µgm-3 (range: 1.3 - 128.7 µgm-3 ) were recorded for PM10 and PM2.5 respectively. These values were found to be above the European Union (EU) and World Health Organisation (WHO) maximum allowable limits. The enrichment factors (EF) computed from elemental composition of the aerosols showed that major elements (Na to Fe) were more enriched in the PM10 fraction than they were in the PM2.5 than fraction, while trace-elements (V to Pb) were more enriched than PM2.5 than in PM10. Positive Matrix Factorisation (PMF) source apportionment allowed us to identify, quantify, and characterize the following aerosol classes: sea salt (17%), soil dust (44%), industrial emissions (3%). Oil Combustion (15%), and biomass burning (21%) for the PM10 - 2.5, fraction. The same five factors were also apportioned in the PM2.5 fraction: sea spray (10%), oil combustion (41%), industrial emission (16%). biomass burning (31%), and soil dust (2%). Sources of anthropogenic pollution (oil combustion, biomass burning, and industrial emission) were the main contributors to the line PM2.5 fraction. while sources of natural origin (sea spray, and soil dust) contributed mainly to the coarse (PM10 - 2.5) fraction. The source profiles revealed the influence of long range aerosol transport and also an episode of the 'Saharan dust' impact during the harmattan season. Particulate matter has been linked to air pollution as an important component of pollutants

  7. Organic composition and source apportionment of fine aerosol at Monterrey, Mexico, based on organic markers

    Science.gov (United States)

    Mancilla, Y.; Mendoza, A.; Fraser, M. P.; Herckes, P.

    2016-01-01

    attribution results obtained using the CMB (chemical mass balance) model indicate that emissions from motor vehicle exhausts are the most important, accounting for the 64 % of the PM2.5, followed by meat-cooking operations with 31 % The vegetative detritus and biomass burning had the smallest contribution (2.2 % of the PM2.5). To our knowledge, this is only the second study to explore the organic composition and source apportionment of fine organic aerosol based on molecular markers in Mexico and the first for the MMA. Particularly molecular marker were quantified by solvent extraction with dichloromethane, derivatization, and gas chromatography with mass spectrometry (GC/MS).

  8. Characterization and source apportionment of polycyclic aromatic hydrocarbons (PAHs) in Sediments from the Bohai Sea, China

    Science.gov (United States)

    Liu, Jihua; Hu, Ningjing; Shi, Xuefa

    2015-04-01

    Characterization and source apportionment of polycyclic aromatic hydrocarbons (PAHs) in Sediments from the Bohai Sea, China Liu Jihua, Hu Ningjing, Shi Xuefa First Institute of Oceanography, State Oceanic Administration, Qingdao 266061, China Polycyclic aromatic hydrocarbons (PAHs) are a class of ubiquitous organic contaminants in the environment. Indeed, 16 PAH compounds have been listed as priority pollutants by the United States Environmental Protection Agency and the European Union because of their potential toxicity to humans and ecosystems. As POPs are released or escape into the environment, their global accumulation in marine sediments generates a complex balance between inputs and outputs. Furthermore, PAHs in coastal sediments can serve as effective tracers of materials transport from land-to-sea (Fang et al., 2009). Hence, investigations of PAHs in sediments can provide useful information for further understanding of environmental processes and material transport. In this study, sixteen polycyclic aromatic hydrocarbons (PAHs) were extracted from a total of 112 surface sediment samples collected across the entire territory of the Bohai Sea. The detectable concentrations of PAHs ranged from 97.2 to 300.7 ng/g across all samples, indicating low contamination levels of PAHs compared with reported values for other coastal sediments in China and developed countries. The highest concentrations were found within three belts in the vicinity of Luan River Estuary-Qinhuangdao Harbor, the Cao River Estuary-Bohai Sea Center, and north of the Yellow River Estuary. The distribution patterns of PAHs and source identification implied that PAH contamination in the Bohai Sea mainly originates from offshore oil exploration, sewage discharge from rivers and shipping activities. Further Principal components analysis (PCA)/multivariate linear regression (MLR) analysis suggested that the contributions of spilled oil products (petrogenic), coal combustion and traffic

  9. Advanced source apportionment of size-resolved trace elements at multiple sites in London during winter

    Science.gov (United States)

    Visser, S.; Slowik, J. G.; Furger, M.; Zotter, P.; Bukowiecki, N.; Canonaco, F.; Flechsig, U.; Appel, K.; Green, D. C.; Tremper, A. H.; Young, D. E.; Williams, P. I.; Allan, J. D.; Coe, H.; Williams, L. R.; Mohr, C.; Xu, L.; Ng, N. L.; Nemitz, E.; Barlow, J. F.; Halios, C. H.; Fleming, Z. L.; Baltensperger, U.; Prévôt, A. S. H.

    2015-10-01

    Trace element measurements in PM10-2.5, PM2.5-1.0 and PM1.0-0.3 aerosol were performed with 2 h time resolution at kerbside, urban background and rural sites during the ClearfLo winter 2012 campaign in London. The environment-dependent variability of emissions was characterized using the Multilinear Engine implementation of the positive matrix factorization model, conducted on data sets comprising all three sites but segregated by size. Combining the sites enabled separation of sources with high temporal covariance but significant spatial variability. Separation of sizes improved source resolution by preventing sources occurring in only a single size fraction from having too small a contribution for the model to resolve. Anchor profiles were retrieved internally by analysing data subsets, and these profiles were used in the analyses of the complete data sets of all sites for enhanced source apportionment. A total of nine different factors were resolved (notable elements in brackets): in PM10-2.5, brake wear (Cu, Zr, Sb, Ba), other traffic-related (Fe), resuspended dust (Si, Ca), sea/road salt (Cl), aged sea salt (Na, Mg) and industrial (Cr, Ni); in PM2.5-1.0, brake wear, other traffic-related, resuspended dust, sea/road salt, aged sea salt and S-rich (S); and in PM1.0-0.3, traffic-related (Fe, Cu, Zr, Sb, Ba), resuspended dust, sea/road salt, aged sea salt, reacted Cl (Cl), S-rich and solid fuel (K, Pb). Human activities enhance the kerb-to-rural concentration gradients of coarse aged sea salt, typically considered to have a natural source, by 1.7-2.2. These site-dependent concentration differences reflect the effect of local resuspension processes in London. The anthropogenically influenced factors traffic (brake wear and other traffic-related processes), dust and sea/road salt provide further kerb-to-rural concentration enhancements by direct source emissions by a factor of 3.5-12.7. The traffic and dust factors are mainly emitted in PM10-2.5 and show strong

  10. Source apportionment of ambient aerosol applying PMF on AMS mobile and stationary data

    Science.gov (United States)

    Mohr, C.; Weimer, S.; Richter, R.; Decarlo, P. F.; Chirico, R.; Heringa, M. F.; Prévôt, A. S. H.; Baltensperger, U.

    2009-04-01

    Ambient aerosols are divided into the categories "primary" and "secondary", referring to particles directly emitted into the air, or formed out of precursor species such as volatile organic compounds, respectively. Main sources for primary urban aerosol and precursor species are traffic emissions, but also wood burning for domestic heating purposes especially in winter time (Alfarra et al., 2007). The quantification of various types of aerosol components is important for source identification which in turn is the basis of all mitigation activities. Positive Matrix Factorization (PMF) is a statistical based source apportionment tool that uses constrained, weighted least squares estimation to determine source profiles and strengths. PMF has been applied recently for the first time on highly time resolved organic mass spectra (Lanz et al., 2007) measured by an Aerodyne aerosol mass spectrometer (AMS) (Canagaratna et al., 2007). For the data presented here, two AMS were deployed together with additional instrumentation in the metropolitan area of Zurich in winter 2007/2008. The high-resolution time-of-flight AMS was stationed at an urban background site in the center, 30 meters from and shielded against direct traffic emissions. The quadrupole-based AMS was deployed in a mobile van allowing for on-road submicron aerosol composition measurements, and investigations into the spatial variability of aerosol concentration and composition. Results indicate that traffic emissions are the main contributor to submicron aerosol concentrations measured on-road. Hydrocarbon-like organic aerosol (HOA), a marker for traffic emissions (Lanz et al. 2007), dominates the primary aerosol mass, together with black carbon (BC). BC was monitored with the MAAP (multi angle absorption photometer). Another significant contributor to primary organic aerosol mass in downtown Zurich is domestic wood burning for heating purposes. Traffic and wood burning emissions make up roughly 50% of the total

  11. Chemical characterization and source apportionment of PM2.5 in Beijing: seasonal perspective

    Directory of Open Access Journals (Sweden)

    R. Zhang

    2013-07-01

    systematic study that comprehensively explores the chemical characterizations and source apportionments of PM2.5 aerosol speciation in Beijing by applying multiple approaches based on a completely seasonal perspective.

  12. Chemical characterization and source apportionment of PM2.5 in Beijing: seasonal perspective

    Directory of Open Access Journals (Sweden)

    R. Zhang

    2013-04-01

    the first systematical study that comprehensively explores the chemical characterizations and source apportionments of PM2.5 aerosol speciation in Beijing by applying multiple approaches based on a completely seasonal perspective.

  13. Chemical characterization and source apportionment of PM2.5 in Beijing: seasonal perspective

    Science.gov (United States)

    Zhang, R.; Jing, J.; Tao, J.; Hsu, S.-C.; Wang, G.; Cao, J.; Lee, C. S. L.; Zhu, L.; Chen, Z.; Zhao, Y.; Shen, Z.

    2013-07-01

    that comprehensively explores the chemical characterizations and source apportionments of PM2.5 aerosol speciation in Beijing by applying multiple approaches based on a completely seasonal perspective.

  14. On the isolation of OC and EC and the optimal strategy of radiocarbon-based source apportionment of carbonaceous aerosols

    Directory of Open Access Journals (Sweden)

    Y. L. Zhang

    2012-07-01

    Full Text Available Radiocarbon (14C measurements of elemental carbon (EC and organic carbon (OC separately (as opposed to only total carbon, TC allow an unambiguous quantification of their non-fossil and fossil sources and represent an improvement in carbonaceous aerosol source apportionment. Isolation of OC and EC for accurate 14C determination requires complete removal of interfering fractions with maximum recovery. To evaluate the extent of positive and negative artefacts during OC and EC separation, we performed sample preparation with a commercial Thermo-Optical OC/EC Analyser (TOA by monitoring the optical properties of the sample during the thermal treatments. Extensive attention has been devoted to the set-up of TOA conditions, in particular, heating program and choice of carrier gas. Based on different types of carbonaceous aerosols samples, an optimised TOA protocol (Swiss_4S with four steps is developed to minimise the charring of OC, the premature combustion of EC and thus artefacts of 14C-based source apportionment of EC. For the isolation of EC for 14C analysis, the water-extraction treatment on the filter prior to any thermal treatment is an essential prerequisite for subsequent radiocarbon; otherwise the non-fossil contribution may be overestimated due to the positive bias from charring. The Swiss_4S protocol involves the following consecutive four steps (S1, S2, S3 and S4: (1 S1 in pure oxygen (O2 at 375 °C for separation of OC for untreated filters, and water-insoluble organic carbon (WINSOC for water-extracted filters; (2 S2 in O2 at 475 °C, followed by (3 S3 in helium (He at 650 °C, aiming at complete OC removal before EC isolation and leading to better consistency with thermal-optical protocols like EUSAAR_2, compared to pure oxygen methods; and (4 S4 in O2 at 760 °C for recovery of the remaining EC.

    WINSOC was found to have a significantly higher fossil

  15. On the isolation of OC and EC and the optimal strategy of radiocarbon-based source apportionment of carbonaceous aerosols

    Directory of Open Access Journals (Sweden)

    Y. L. Zhang

    2012-11-01

    Full Text Available Radiocarbon (14C measurements of elemental carbon (EC and organic carbon (OC separately (as opposed to only total carbon, TC allow an unambiguous quantification of their non-fossil and fossil sources and represent an improvement in carbonaceous aerosol source apportionment. Isolation of OC and EC for accurate 14C determination requires complete removal of interfering fractions with maximum recovery. The optimal strategy for 14C-based source apportionment of carbonaceous aerosols should follow an approach to subdivide TC into different carbonaceous aerosol fractions for individual 14C analyses, as these fractions may differ in their origins. To evaluate the extent of positive and negative artefacts during OC and EC separation, we performed sample preparation with a commercial Thermo-Optical OC/EC Analyser (TOA by monitoring the optical properties of the sample during the thermal treatments. Extensive attention has been devoted to the set-up of TOA conditions, in particular, heating program and choice of carrier gas. Based on different types of carbonaceous aerosols samples, an optimised TOA protocol (Swiss_4S with four steps is developed to minimise the charring of OC, the premature combustion of EC and thus artefacts of 14C-based source apportionment of EC. For the isolation of EC for 14C analysis, the water-extraction treatment on the filter prior to any thermal treatment is an essential prerequisite for subsequent radiocarbon measurements; otherwise the non-fossil contribution may be overestimated due to the positive bias from charring. The Swiss_4S protocol involves the following consecutive four steps (S1, S2, S3 and S4: (1 S1 in pure oxygen (O2 at 375 °C for separation of OC for untreated filters and water-insoluble organic carbon (WINSOC for water-extracted filters; (2 S2 in O2 at 475 °C followed by (3 S3 in helium (He at 650 °C, aiming at complete

  16. On the isolation of OC and EC and the optimal strategy of radiocarbon-based source apportionment of carbonaceous aerosols

    Science.gov (United States)

    Zhang, Y. L.; Perron, N.; Ciobanu, V. G.; Zotter, P.; Minguillón, M. C.; Wacker, L.; Prévôt, A. S. H.; Baltensperger, U.; Szidat, S.

    2012-11-01

    Radiocarbon (14C) measurements of elemental carbon (EC) and organic carbon (OC) separately (as opposed to only total carbon, TC) allow an unambiguous quantification of their non-fossil and fossil sources and represent an improvement in carbonaceous aerosol source apportionment. Isolation of OC and EC for accurate 14C determination requires complete removal of interfering fractions with maximum recovery. The optimal strategy for 14C-based source apportionment of carbonaceous aerosols should follow an approach to subdivide TC into different carbonaceous aerosol fractions for individual 14C analyses, as these fractions may differ in their origins. To evaluate the extent of positive and negative artefacts during OC and EC separation, we performed sample preparation with a commercial Thermo-Optical OC/EC Analyser (TOA) by monitoring the optical properties of the sample during the thermal treatments. Extensive attention has been devoted to the set-up of TOA conditions, in particular, heating program and choice of carrier gas. Based on different types of carbonaceous aerosols samples, an optimised TOA protocol (Swiss_4S) with four steps is developed to minimise the charring of OC, the premature combustion of EC and thus artefacts of 14C-based source apportionment of EC. For the isolation of EC for 14C analysis, the water-extraction treatment on the filter prior to any thermal treatment is an essential prerequisite for subsequent radiocarbon measurements; otherwise the non-fossil contribution may be overestimated due to the positive bias from charring. The Swiss_4S protocol involves the following consecutive four steps (S1, S2, S3 and S4): (1) S1 in pure oxygen (O2) at 375 °C for separation of OC for untreated filters and water-insoluble organic carbon (WINSOC) for water-extracted filters; (2) S2 in O2 at 475 °C followed by (3) S3 in helium (He) at 650 °C, aiming at complete OC removal before EC isolation and leading to better consistency with thermal-optical protocols

  17. Source apportionment of particles at Station Nord, North East Greenland during 2008–2010 using COPREM and PMF analysis

    Directory of Open Access Journals (Sweden)

    A. Massling

    2012-09-01

    Full Text Available In order to develop strategies for controlling and reducing Arctic air pollution, there is a need to understand the basic mechanisms for determining the fate of air pollution in the Arctic. Sources of atmospheric particles at Station Nord (81°36' N, 16°40' W in North East Greenland were evaluated for a two-year period from March 2008 to February 2010. Source apportionment using Positive Matrix Factorization (PMF and COnstrained Physical Receptor Model (COPREM was based on measurements of black carbon, elements (Al, Si, S, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, As, Se, Br, Rb, Sr, Zr, Pb and inorganic ions (SO2, SO42−, Na+, NH4+, NO3−, Cl−. In general, source apportionment results by PMF and COPREM showed good agreement. Five sources adequately explained the measurements, which included a Marine and a Soil source of natural origin and three additional anthropogenic sources, which were all influenced by metal industries. One anthropogenic source was dominated by Zn of which air mass back trajectories using the Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT model suggested a Canadian Arctic origin, despite certain influences from southern and eastern origins. Another anthropogenic source was characterised by high concentrations of Pb and As, which has been historically referred to as a Combustion source at Station Nord. The impacts of large-scale industry in Siberia, Russia were evident through high Cu concentrations in both the Combustion source and an additional Cu/Ni source. Br correlated well with the anthropogenic species S and Pb though the elements are unlikely to have a common origin. More likely, sulphuric acid aerosols serve as transport containers for Br species of marine or local origin. Of particular relevance to climate, sources of black carbon were identified to be mainly anthropogenic and most probably of Siberian origin (80–98%.

  18. Source Apportionment of Elemental Carbon Across the San Francisco Bay Area Using Combined Radiocarbon and Chemical Mass Balances

    Science.gov (United States)

    Yoon, S.; Fairley, D.; Sheesley, R. J.

    2014-12-01

    The San Francisco Bay Area is impacted by ambient particulate matter (PM) from a variety of sources including motor vehicles, biomass burning, off-road vehicles, industry, and meat cooking. Ambient PM, especially fine PM (diameter less than 2.5μm, PM2.5), is known to negatively impact health. Elemental Carbon (EC) is one of the major constituents of PM2.5. It not only negatively affects health but is also a powerful short-lived climate forcer. The State of California and Bay Area Air Quality Management District (BAAQMD) have made efforts in regulating contribution of EC from diesel trucks and wood burning, respectively. These and other efforts have assisted in significantly reducing the annual average PM2.5 concentrations approximately 30% since 2005 and 70% since 1990. Despite these improvements, to better determine the relative contribution of contemporary vs. fossil carbon, radiocarbon source apportionment of EC was conducted on PM2.5 collected in the Bay Area. Measurements of the abundance of 14C in the EC fractions are used to quantify the relative contributions of fossil carbon (fossil fuel combustion, including motor vehicle exhaust) and contemporary carbon (biomass combustion and meat cooking). This comprehensive study included seven sites in the Bay Area and 12 months of sampling starting November 2011 through October 2012. The samples were composited to represent winter (November-February) and non-winter (March-October). In addition to radiocarbon analysis, Chemical Mass Balance (CMB) analysis using bulk PM2.5 composition and selected trace gases was used to understand the split among gasoline, natural gas, and diesel exhaust. Preliminary apportionment of the seven sites shows roughly equal contributions of fossil fuel and biomass burning/cooking for both winter and non-winter samples. There is evidence that the diesel contribution to EC, in particular, has decreased substantially over the last decade.

  19. Studying organic aerosols during bonfire night in Manchester: ME-2 source apportionment

    Science.gov (United States)

    Reyes Villegas, Ernesto; Allan, James

    2016-04-01

    conditions: 5°C in 2014; 12°C in 2013. For NH4NO3, a range of 1.5-2.9 for the ratio of concentrations NO+/NO+2 (m/z ratio of 30:46) has previously been reported (Fry et al. 2009) while the ratio for organic nitrate is much higher, with values of 10-15 (Hao et al. 2014). In this study, a ratio of 9.5 was observed on bonfire night and a ratio of 3.5 was observed during episodes without bonfire/fireworks emissions. This study shows OA source apportionment on bonfire night where significant SFOA emissions are present, suggesting that high concentrations are not only attributed to bonfires/fireworks emissions but also to meteorological conditions. Organic nitrate was identified during bonfire night suggesting a nighttime chemistry with anthropogenic oxidants. This analysis may provide vital information to strengthen legislation as well as to support health studies in order to improve air quality in the UK. Canonaco, F. et al. Atmos Meas Tech. 6, 3649-3661, 2013. Fry, J. et al. Atmos. Chem. Phys. 9, 1431-1449, 2009. Hao, L. Atmos. Chem. Phys., 14, 13483-13495, 2014. Zhao, S. et al. Atmospheric Pollution Research. 5, 335-343, 2014.

  20. AIRUSE-LIFE+: a harmonized PM speciation and source apportionment in five southern European cities

    Science.gov (United States)

    Amato, Fulvio; Alastuey, Andrés; Karanasiou, Angeliki; Lucarelli, Franco; Nava, Silvia; Calzolai, Giulia; Severi, Mirko; Becagli, Silvia; Gianelle, Vorne L.; Colombi, Cristina; Alves, Celia; Custódio, Danilo; Nunes, Teresa; Cerqueira, Mario; Pio, Casimiro; Eleftheriadis, Konstantinos; Diapouli, Evangelia; Reche, Cristina; Cruz Minguillón, María; Manousakas, Manousos-Ioannis; Maggos, Thomas; Vratolis, Stergios; Harrison, Roy M.; Querol, Xavier

    2016-03-01

    The AIRUSE-LIFE+ project aims at characterizing similarities and heterogeneities in particulate matter (PM) sources and contributions in urban areas from southern Europe. Once the main PMx sources are identified, AIRUSE aims at developing and testing the efficiency of specific and non-specific measures to improve urban air quality. This article reports the results of the source apportionment of PM10 and PM2.5 conducted at three urban background sites (Barcelona, Florence and Milan, BCN-UB, FI-UB and MLN-UB), one suburban background site (Athens, ATH-SUB) and one traffic site (Porto, POR-TR). After collecting 1047 PM10 and 1116 PM2.5 24 h samples during 12 months (from January 2013 on) simultaneously at the five cities, these were analysed for the contents of OC, EC, anions, cations, major and trace elements and levoglucosan. The USEPA PMF5 receptor model was applied to these data sets in a harmonized way for each city. The sum of vehicle exhaust (VEX) and non-exhaust (NEX) contributes between 3.9 and 10.8 µg m-3 (16-32 %) to PM10 and 2.3 and 9.4 µg m-3 (15-36 %) to PM2.5, although a fraction of secondary nitrate is also traffic-related but could not be estimated. Important contributions arise from secondary particles (nitrate, sulfate and organics) in PM2.5 (37-82 %) but also in PM10 (40-71 %), mostly at background sites, revealing the importance of abating gaseous precursors in designing air quality plans. Biomass burning (BB) contributions vary widely, from 14-24 % of PM10 in POR-TR, MLN-UB and FI-UB, 7 % in ATH-SUB, to < 2 % in BCN-UB. In PM2.5, BB is the second most important source in MLN-UB (21 %) and in POR-TR (18 %), the third one in FI-UB (21 %) and ATH-SUB (11 %), but is again negligible (< 2 %) in BCN-UB. This large variability among cities is mostly due to the degree of penetration of biomass for residential heating. In Barcelona natural gas is very well supplied across the city and is used as fuel in 96 % of homes, while in other cities, PM levels

  1. Bioavailability of Polycyclic Aromatic Hydrocarbons and their Potential Application in Eco-risk Assessment and Source Apportionment in Urban River Sediment

    Science.gov (United States)

    Yang, Xunan; Yu, Liuqian; Chen, Zefang; Xu, Meiying

    2016-03-01

    Traditional risk assessment and source apportionment of sediments based on bulk polycyclic aromatic hydrocarbons (PAHs) can introduce biases due to unknown aging effects in various sediments. We used a mild solvent (hydroxypropyl-β-cyclodextrin) to extract the bioavailable fraction of PAHs (a-PAHs) from sediment samples collected in Pearl River, southern China. We investigated the potential application of this technique for ecological risk assessments and source apportionment. We found that the distribution of PAHs was associated with human activities and that the a-PAHs accounted for a wide range (4.7%-21.2%) of total-PAHs (t-PAHs), and high risk sites were associated with lower t-PAHs but higher a-PAHs. The correlation between a-PAHs and the sediment toxicity assessed using tubificid worms (r = -0.654, P = 0.021) was greater than that from t-PAH-based risk assessment (r = -0.230, P = 0.472). Moreover, the insignificant correlation between a-PAH content and mPEC-Q of low molecular weight PAHs implied the potiential bias of t-PAH-based risk assessment. The source apportionment from mild extracted fractions was consistent across different indicators and was in accordance with typical pollution sources. Our results suggested that mild extraction-based approaches reduce the potential error from aging effects because the mild extracted PAHs provide a more direct indicator of bioavailability and fresher fractions in sediments.

  2. Variations in source apportionments of nutrient load among seasons and hydrological years in a semi-arid watershed: GWLF model results.

    Science.gov (United States)

    Du, Xinzhong; Li, Xuyong; Zhang, Wangshou; Wang, Huiliang

    2014-05-01

    Quantifying source apportionments of nutrient load and their variations among seasons and hydrological years can provide useful information for watershed nutrient load reduction programs. There are large seasonal and inter-annual variations in nutrient loads and their sources in semi-arid watersheds that have a monsoon climate. The Generalized Watershed Loading Function model was used to simulate monthly nutrient loads from 2004 to 2011 in the Liu River watershed, Northern China. Model results were used to investigate nutrient load contributions from different sources, temporal variations of source apportionments and the differences in the behavior of total nitrogen (TN) and total phosphorus (TP). Examination of source apportionments for different seasons showed that point sources were the main source of TN and TP in the non-flood season, whereas contributions from diffuse sources, such as rural runoff, soil erosion, and urban areas, were much higher in the flood season. Furthermore, results for three typical hydrological years showed that the contribution ratios of nutrient loads from point sources increased as streamflow decreased, while contribution ratios from rural runoff and urban area increased as streamflow increased. Further, there were significant differences between TN and TP sources on different time scales. Our findings suggest that priority actions and management measures should be changed for different time periods and hydrological conditions, and that different strategies should be used to reduce loads of nitrogen and phosphorus effectively.

  3. Size-resolved source apportionment of carbonaceous particulate matter in urban and rural sites in central California

    Science.gov (United States)

    Ham, Walter A.; Kleeman, Michael J.

    2011-08-01

    Very little is currently known about the relationship between exposure to different sources of ambient ultrafine particles (PM 0.1) and human health effects. If human health effects are enhanced by PM 0.1's ability to cross cell membranes, then more information is needed describing the sources of ultrafine particles that are deposited in the human respiratory system. The current study presents results for the source apportionment of airborne particulate matter in six size fractions smaller than 1.8 μm particle diameter including ultrafine particles (PM 0.1) in one of the most polluted air basins in the United States. Size-resolved source apportionment results are presented at an urban site and rural site in central California's heavily polluted San Joaquin Valley during the winter and summer months using a molecular marker chemical mass balance (MM-CMB) method. Respiratory deposition calculations for the size-resolved source apportionment results are carried out with the Multiple Path Particle Dosimetry Model ( MPPD v 2.0), including calculations for ultrafine (PM 0.1) source deposition. Diesel engines accounted for the majority of PM 0.1 and PM 1.8 EC at both the urban and rural sampling locations during both summer and winter seasons. Meat cooking accounted for 33-67% and diesel engines accounted for 15-21% of the PM 0.1 OC at Fresno. Meat cooking accounted for 22-26% of the PM 0.1 OC at the rural Westside location, while diesel engines accounted for 8-9%. Wood burning contributions to PM 0.1 OC increased to as much as 12% of PM 0.1 OC during the wintertime. The modest contribution of wood smoke reflects the success of emissions control programs over the past decade. In contrast to PM 0.1, PM 1.8 OC had a higher fraction of unidentified source contributions (68-85%) suggesting that this material is composed of secondary organic aerosol (SOA) or primary organic aerosol (POA) that has been processed by atmospheric chemical reactions. Meat cooking was the largest

  4. Development of PM2.5 source impact spatial fields using a hybrid source apportionment air quality model

    Directory of Open Access Journals (Sweden)

    C. E. Ivey

    2015-01-01

    Full Text Available An integral part of air quality management is knowledge of the impact of pollutant sources on ambient concentrations of particulate matter (PM. There is also a growing desire to directly use source impact estimates in health studies; however, source impacts cannot be directly measured. Several limitations are inherent in most source apportionment methods, which has led to the development of a novel hybrid approach that is used to estimate source impacts by combining the capabilities of receptor modeling (RM and chemical transport modeling (CTM. The hybrid CTM-RM method calculates adjustment factors to refine the CTM-estimated impact of sources at monitoring sites using pollutant species observations and the results of CTM sensitivity analyses, though it does not directly generate spatial source impact fields. The CTM used here is the Community Multi-Scale Air Quality (CMAQ model, and the RM approach is based on the Chemical Mass Balance model. This work presents a method that utilizes kriging to spatially interpolate source-specific impact adjustment factors to generate revised CTM source impact fields from the CTM-RM method results, and is applied to January 2004 over the continental United States. The kriging step is evaluated using data withholding and by comparing results to data from alternative networks. Directly applied and spatially interpolated hybrid adjustment factors at withheld monitors had a correlation coefficient of 0.89, a linear regression slope of 0.83 ± 0.02, and an intercept of 0.14 ± 0.02. Refined source contributions reflect current knowledge of PM emissions (e.g., significant differences in biomass burning impact fields. Concentrations of 19 species and total PM2.5 mass were reconstructed for withheld monitors using directly applied and spatially interpolated hybrid adjustment factors. The mean concentrations of total PM2.5 for withheld monitors were 11.7 (± 8.3, 16.3 (± 11, 8.59 (± 4.7, and 9.20 (± 5.7 μg m−3

  5. Source apportionment of PM2.5 in top polluted cities in Hebei, China using the CMAQ model

    Science.gov (United States)

    Wang, Litao; Wei, Zhe; Wei, Wei; Fu, Joshua S.; Meng, Chenchen; Ma, Simeng

    2015-12-01

    Hebei has been recognized as one of the most polluted provinces in China, characterized by extremely high concentrations of fine particulate matter (PM2.5) in many of its cities, especially those located in the southern area of the province and highly potentially northward transported to Beijing. Source apportionment of PM2.5 is the basis and prerequisite of an effective control strategy. In this study, the Mesoscale Modeling System Generation 5 (MM5) and the Models-3/Community Multiscale Air Quality (CMAQ) modeling system are applied to East Asia and North China at 36- and 12-km horizontal grid resolutions, and the source apportionment of PM2.5 in the three top polluted cities in Hebei, i.e., Shijiazhuang, Xingtai, and Handan, is performed using the Brute-Force method. It is concluded that the regional source contributions to PM2.5 are 27.9% in Shijiazhuang, 46.6% in Xingtai, and 40.4% in Handan. The major local contributors are industrial, domestic and agricultural sources in all the three cities with the contributions of 39.8%, 15.8%, and 10.6% in Shijiazhuang, 30.5%, 13.6%, and 6.9% in Xingtai, 35.9%, 13.5%, and 6.2% in Handan, respectively. As to the secondary aerosols of sulfate (SO42-), nitrate (NO3-), and ammonium (NH4+) in PM2.5, which are important chemical species in PM2.5 (about 30-40% in PM2.5) and cannot be further apportioned by receptor models, the regional source contributions to the total concentrations of SO42-, NO3-, and NH4+ are 40.9%, 62.0%, and 59.1% in Shijiazhuang, Xingtai, and Handan, respectively. The local industrial, domestic and agricultural contributions to those are 23.7%, 6.6%, and 29.8% in total in Shijiazhuang, 17.5%, 5.0%, and 17.7% in Xingtai, and 20.6%, 4.8%, and 17.8% in Handan, respectively. The regional joint controls of air pollution are more important in Xingtai and Handan than in Shijiazhuang, and the emission controls of agricultural sources need to be further considered in the future policy.

  6. Source apportionment of particles at Station Nord, North East Greenland during 2008–2010 using COPREM and PMF analysis

    Directory of Open Access Journals (Sweden)

    Q. T. Nguyen

    2013-01-01

    Full Text Available In order to develop strategies for controlling and reducing Arctic air pollution, there is a need to understand the basic mechanisms for determining the fate of air pollution in the Arctic. Sources of atmospheric particles at Station Nord (81° 36' N, 16° 40' W in North East Greenland were evaluated for a two-year period from March 2008 to February 2010. Source apportionment using Positive Matrix Factorization (PMF and COnstrained Physical REceptor Model (COPREM was based on measurements of black carbon, elements (Al, Si, S, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, As, Se, Br, Rb, Sr, Zr, Pb and inorganic ions (SO2, SO42−, Na+, NH4+, NO3, Cl2−. In general, source apportionment results by PMF and COPREM showed good agreement. Five sources adequately explained the measurements, which included a Marine and a Soil source of natural origin and three additional anthropogenic sources, which were all influenced by metal industries. One anthropogenic source was dominated by Zn of which air mass back trajectories using the Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT model suggested a Canadian Arctic origin, despite certain influences from Southern and Eastern origins. Another anthropogenic source was characterised by high concentrations of Pb and As, which has been historically referred to as a Combustion source at Station Nord. The impacts of large-scale industry in Siberia, Russia were evident through high Cu concentrations in both the Combustion source and an additional Cu/Ni source.

    Br correlated well with the anthropogenic species S and Pb though the elements are unlikely to have a common origin. More likely, sulphuric acid aerosols serve as transport containers for Br species of marine origin. Of particular relevance to climate, sources of black carbon were identified to be

  7. Online coupling of pure O2 thermo-optical methods - 14C AMS for source apportionment of carbonaceous aerosols

    Science.gov (United States)

    Agrios, Konstantinos; Salazar, Gary; Zhang, Yan-Lin; Uglietti, Chiara; Battaglia, Michael; Luginbühl, Marc; Ciobanu, Viorela Gabriela; Vonwiller, Matthias; Szidat, Sönke

    2015-10-01

    This paper reports on novel separation methods developed for the direct determination of 14C in organic carbon (OC) and elemental carbon (EC), two sub-fractions of total carbon (TC) of atmospheric air particulate matter. Until recently, separation of OC and EC has been performed off-line by manual and time-consuming techniques that relied on the collection of massive CO2 fractions. We present here two on-line hyphenated techniques between a Sunset OC/EC analyzer and a MICADAS (MIni radioCArbon DAting System) accelerator mass spectrometer (AMS) equipped with a gas ion source. The first implementation facilitates the direct measurement in the low sample size range (<10 μg C) with high throughput on a routine basis, while the second explores the potential for a continuous-flow real-time CO2 gas feed into the ion source. The performance achieved with reference materials and real atmospheric samples will be discussed to draw conclusions on the improvement offered in the field of 14C aerosol source apportionment.

  8. The source apportionment of polycyclic aromatic hydrocarbons (PAHs) in the topsoil in Xiaodian sewage irrigation area, North of China.

    Science.gov (United States)

    Li, Jia-Le; Wang, Yan-Xin; Zhang, Cai-Xiang; Dong, Yi-Hui; Du, Bin; Liao, Xiao-Ping

    2014-12-01

    31 topsoil samples were collected by grid method in Xiaodian sewage irrigation area, Taiyuan City, North of China. The concentrations of 16 kinds of polycyclic aromatic hydrocarbons (PAHs) were determined by gas chromatograph coupled with mass spectrum. Generally speaking, the distribution order of PAHs in the area is: those with five and six rings > those with four rings > those with two and three rings. Source apportionment shows a significant zonation of the source of PAHs: the civil coal pollution occurred in the north part, the local and far factory pollution happened in the middle area and the mixed pollution sources from coal and wood combustion, automotive emission, presented in the south area. The distribution of PAHs has a definite relationship with the sewage water flow and soil adsorption. The related coefficient between PAHs and physicochemical property showed there was a negative correlation between pH, silt, clay and PAHs while there was a positive correlation between total organic carbon, sand and PAHs. PMID:25139034

  9. Measurement and apportionment of radon source terms for modeling indoor environments. Final progress report, March 1990--August 1992

    Energy Technology Data Exchange (ETDEWEB)

    Harley, N.H.

    1992-12-31

    During the present 2 1/2 year contract period, we have made significant Progress in modeling the source apportionment of indoor {sup 222}Rn and in {sup 222}Rn decay product dosimetry. Two additional areas were worked on which we believe are useful for the DOE Radon research Program. One involved an analysis of the research house data, grouping the hourly house {sup 222}Rn measurements into 2 day, 7 day and 90 day intervals to simulate the response of passive monitors. Another area requiring some attention resulted in a publication of 3 years of our indoor/outdoor measurements in a high-rise apartment. Little interest has been evinced in apartment measurements yet 20% of the US population lives in multiple-family dwellings, not in contact with the ground. These data together with a summary of all other published data on apartments showed that apartments have only about 50% greater {sup 222}Rn concentration than the measured outdoor {sup 222}Rn. Apartment dwellers generally represent a low risk group regarding {sup 222}Rn exposure. The following sections describe the main projects in some detail.

  10. Evaluation and Source Apportionment of Heavy Metals (HMs in Sewage Sludge of Municipal Wastewater Treatment Plants (WWTPs in Shanxi, China

    Directory of Open Access Journals (Sweden)

    Baoling Duan

    2015-12-01

    Full Text Available Heavy metals (HMs in sewage sludge have become the crucial limiting factors for land use application. Samples were collected and analyzed from 32 waste water treatment plants (WWTPs in the Shanxi Province, China. HM levels in sewage sludge were assessed. The multivariate statistical method principal component analysis (PCA was applied to identify the sources of HMs in sewage sludge. HM pollution classes by geochemical accumulation index Igeo and correlation analyses between HMs were also conducted. HMs were arranged in the following decreasing order of mean concentration: Zn > Cu > Cr > Pb > As > Hg > Cd; the maximum concentrations of all HMs were within the limit of maximum content permitted by Chinese discharge standard. Igeo classes of HMs pollution in order from most polluted to least were: Cu and Hg pollution were the highest; Cd and Cr pollution were moderate; Zn, As and Pb pollution were the least. Sources of HM contamination in sewage sludge were identified as three components. The primary contaminant source accounting for 35.7% of the total variance was identified as smelting industry, coking plant and traffic sources; the second source accounting for 29.0% of the total variance was distinguished as household and water supply pollution; the smallest of the three sources accounting for 16.2% of the total variance was defined as special industries such as leather tanning, textile manufacturing and chemical processing industries. Source apportionment of HMs in sewage sludge can control HM contamination through suggesting improvements in government policies and industrial processes.

  11. Evaluation and Source Apportionment of Heavy Metals (HMs) in Sewage Sludge of Municipal Wastewater Treatment Plants (WWTPs) in Shanxi, China.

    Science.gov (United States)

    Duan, Baoling; Liu, Fenwu; Zhang, Wuping; Zheng, Haixia; Zhang, Qiang; Li, Xiaomei; Bu, Yushan

    2015-12-01

    Heavy metals (HMs) in sewage sludge have become the crucial limiting factors for land use application. Samples were collected and analyzed from 32 waste water treatment plants (WWTPs) in the Shanxi Province, China. HM levels in sewage sludge were assessed. The multivariate statistical method principal component analysis (PCA) was applied to identify the sources of HMs in sewage sludge. HM pollution classes by geochemical accumulation index I(geo) and correlation analyses between HMs were also conducted. HMs were arranged in the following decreasing order of mean concentration: Zn > Cu > Cr > Pb > As > Hg > Cd; the maximum concentrations of all HMs were within the limit of maximum content permitted by Chinese discharge standard. I(geo) classes of HMs pollution in order from most polluted to least were: Cu and Hg pollution were the highest; Cd and Cr pollution were moderate; Zn, As and Pb pollution were the least. Sources of HM contamination in sewage sludge were identified as three components. The primary contaminant source accounting for 35.7% of the total variance was identified as smelting industry, coking plant and traffic sources; the second source accounting for 29.0% of the total variance was distinguished as household and water supply pollution; the smallest of the three sources accounting for 16.2% of the total variance was defined as special industries such as leather tanning, textile manufacturing and chemical processing industries. Source apportionment of HMs in sewage sludge can control HM contamination through suggesting improvements in government policies and industrial processes. PMID:26690464

  12. Critical review and meta-analysis of ambient particulate matter source apportionment using receptor models in Europe

    Science.gov (United States)

    Belis, C. A.; Karagulian, F.; Larsen, B. R.; Hopke, P. K.

    2013-04-01

    A review was conducted of the published literature on source apportionment of ambient particulate matter (PM) in Europe using receptor models (RMs). Consistent records were identified for source contribution estimates of PM mass concentrations for 272 records and of organic carbon (OC) in PM for 60 records. Over the period 2000-2012, a shift was observed in the use of RMs from principal component analysis, enrichment factors, and classical factor analysis to Positive Matrix Factorization while Chemical Mass Balance is still topical. Following a meta-analysis of the published results, six major source categories for PM were defined that comprise almost all individual sources apportioned in Europe: atmospheric formation of secondary inorganic aerosol (SIA), traffic, re-suspension of crustal/mineral dust, biomass burning, (industrial) point sources, and sea/road salt. For the OC fraction, the three main source categories were: atmospheric formation of secondary organic aerosol, biomass burning, and fossil fuel combustion. The geographical and seasonal variations of these sources are mapped and discussed. A special analysis of PM concentrations that exceed the current European air quality limits indicated SIA and traffic as the most important source categories to target for abatement throughout the year together with biomass burning during the cold season.

  13. Integrated Application of Multivariate Statistical Methods to Source Apportionment of Watercourses in the Liao River Basin, Northeast China

    Science.gov (United States)

    Chen, Jiabo; Li, Fayun; Fan, Zhiping; Wang, Yanjie

    2016-01-01

    Source apportionment of river water pollution is critical in water resource management and aquatic conservation. Comprehensive application of various GIS-based multivariate statistical methods was performed to analyze datasets (2009–2011) on water quality in the Liao River system (China). Cluster analysis (CA) classified the 12 months of the year into three groups (May–October, February–April and November–January) and the 66 sampling sites into three groups (groups A, B and C) based on similarities in water quality characteristics. Discriminant analysis (DA) determined that temperature, dissolved oxygen (DO), pH, chemical oxygen demand (CODMn), 5-day biochemical oxygen demand (BOD5), NH4+–N, total phosphorus (TP) and volatile phenols were significant variables affecting temporal variations, with 81.2% correct assignments. Principal component analysis (PCA) and positive matrix factorization (PMF) identified eight potential pollution factors for each part of the data structure, explaining more than 61% of the total variance. Oxygen-consuming organics from cropland and woodland runoff were the main latent pollution factor for group A. For group B, the main pollutants were oxygen-consuming organics, oil, nutrients and fecal matter. For group C, the evaluated pollutants primarily included oxygen-consuming organics, oil and toxic organics. PMID:27775679

  14. Evaluation and Source Apportionment of Heavy Metals (HMs) in Sewage Sludge of Municipal Wastewater Treatment Plants (WWTPs) in Shanxi, China

    Science.gov (United States)

    Duan, Baoling; Liu, Fenwu; Zhang, Wuping; Zheng, Haixia; Zhang, Qiang; Li, Xiaomei; Bu, Yushan

    2015-01-01

    Heavy metals (HMs) in sewage sludge have become the crucial limiting factors for land use application. Samples were collected and analyzed from 32 waste water treatment plants (WWTPs) in the Shanxi Province, China. HM levels in sewage sludge were assessed. The multivariate statistical method principal component analysis (PCA) was applied to identify the sources of HMs in sewage sludge. HM pollution classes by geochemical accumulation index Igeo and correlation analyses between HMs were also conducted. HMs were arranged in the following decreasing order of mean concentration: Zn > Cu > Cr > Pb > As > Hg > Cd; the maximum concentrations of all HMs were within the limit of maximum content permitted by Chinese discharge standard. Igeo classes of HMs pollution in order from most polluted to least were: Cu and Hg pollution were the highest; Cd and Cr pollution were moderate; Zn, As and Pb pollution were the least. Sources of HM contamination in sewage sludge were identified as three components. The primary contaminant source accounting for 35.7% of the total variance was identified as smelting industry, coking plant and traffic sources; the second source accounting for 29.0% of the total variance was distinguished as household and water supply pollution; the smallest of the three sources accounting for 16.2% of the total variance was defined as special industries such as leather tanning, textile manufacturing and chemical processing industries. Source apportionment of HMs in sewage sludge can control HM contamination through suggesting improvements in government policies and industrial processes. PMID:26690464

  15. Source and risk apportionment of selected VOCs and PM2.5 species using partially constrained receptor models with multiple time resolution data

    International Nuclear Information System (INIS)

    This study was conducted to identify and quantify the sources of selected volatile organic compounds (VOCs) and fine particulate matter (PM2.5) by using a partially constrained source apportionment model suitable for multiple time resolution data. Hourly VOC, 12-h and 24-h PM2.5 speciation data were collected during three seasons in 2013. Eight factors were retrieved from the Positive Matrix Factorization solutions and adding source profile constraints enhanced the interpretability of source profiles. Results showed that the evaporative emission factor was the largest contributor (25%) to VOC mass concentration, while the largest contributor to PM2.5 mass concentration was soil dust/regional transport related factor (26%). In terms of risk prioritization, traffic/industry related factor was the major cause for benzene, ethylbenzene, Cr, and polycyclic aromatic hydrocarbons (29–69%) while petrochemical related factor contributed most to the Ni risk (36%). This indicated that a larger contributor to mass concentration may not correspond to a higher risk. - Highlights: • We applied a partially constrained receptor model to multiple time resolution data. • Hourly VOC, 12-h and 24-h PM2.5 speciation data were combined in the model. • Adding constraints to the model enhanced the interpretability of source profiles. • We applied a risk apportionment approach to obtain the source-specific risk values. • A larger contributor to mass concentration may not correspond to a higher risk. - Combining a constrained receptor model and a risk apportionment approach could provide valuable information to design effective control strategies

  16. Source apportionment of PM2.5 at a regional background site in North China using PMF linked with radiocarbon analysis: insight into the contribution of biomass burning

    Science.gov (United States)

    Zong, Zheng; Wang, Xiaoping; Tian, Chongguo; Chen, Yingjun; Qu, Lin; Ji, Ling; Zhi, Guorui; Li, Jun; Zhang, Gan

    2016-09-01

    Source apportionment of fine particles (PM2.5) at a background site in North China in the winter of 2014 was done using statistical analysis, radiocarbon (14C) measurement and positive matrix factorization (PMF) modeling. Results showed that the concentration of PM2.5 was 77.6 ± 59.3 µg m-3, of which sulfate (SO42-) concentration was the highest, followed by nitrate (NO3-), organic carbon (OC), elemental carbon (EC) and ammonium (NH4+). As demonstrated by backward trajectory, more than half of the air masses during the sampling period were from the Beijing-Tianjin-Hebei (BTH) region, followed by Mongolia and the Shandong Peninsula. Cluster analysis of chemical species suggested an obvious signal of biomass burning in the PM2.5 from the Shandong Peninsula, while the PM2.5 from the BTH region showed a vehicle emission pattern. This finding was further confirmed by the 14C measurement of OC and EC in two merged samples. The 14C result indicated that biogenic and biomass burning emission contributed 59 ± 4 and 52 ± 2 % to OC and EC concentrations, respectively, when air masses originated from the Shandong Peninsula, while the contributions fell to 46 ± 4 and 38 ± 1 %, respectively, when the prevailing wind changed and came from the BTH region. The minimum deviation between source apportionment results from PMF and 14C measurement was adopted as the optimal choice of the model exercises. Here, two minor overestimates with the same range (3 %) implied that the PMF result provided a reasonable source apportionment of the regional PM2.5 in this study. Based on the PMF modeling, eight sources were identified; of these, coal combustion, biomass burning and vehicle emission were the main contributors of PM2.5, accounting for 29.6, 19.3 and 15.9 %, respectively. Compared with overall source apportionment, the contributions of vehicle emission, mineral dust, coal combustion and biomass burning increased when air masses came from the BTH region, Mongolia and the Shandong

  17. Source apportionment of elevated BaP concentrations in PM10 aerosols in an alpine valley in Austria

    Science.gov (United States)

    Bauer, Heidi; Puxbaum, Hans; Jankowski, Nicole; Sampaio Cordeiro Wagner, Lylian

    2010-05-01

    INTRODUCTION: In a village situated at 1215 m a.s.l. in a natural preserve in an Austrian alpine valley elevated BaP concentrations have been measured in the last years. A highly frequented highway leading from Italy to Germany passes near the village. Monthly means of particulate BaP concentrations show a clear seasonal trend with values below 1 ng/m³ during the warmer months and with concentrations up to 9 ng/m³ in the cold season. Annual averages in the years 2000 - 2005 ranged between 1.4 and 2.8 ng/m³ - much higher than the EU target value of 1 ng/m³. We used a macrotracer model developed at the Vienna University of Technology to determine the contributions of the sources for BaP emissions, which were mainly space heating with wood and traffic from the highway. EXPERIMENTAL: The macrotracer concept is a nine component model to derive source contribution and explains 80-100% of PM10 aerosols in Austria. The amount of traffic exhaust is derived by using EC as tracer, whereas EC produced by wood burning is subtracted, the amount of wood smoke is derived by the anhydro-sugar levoglucosan and the ratio between the anhydro-sugars levoglucosan and mannosan. For the source apportionment of BaP the applied factors reflect on the one hand the composition of the automotive fleet in Austria and on the other hand the composition of the fire wood in the region. Filter samples collected with a high volume sampler in winter were analyzed for PM10 aerosol mass, total, organic, elemental and carbonate carbon, HULIS, anhydro-sugars, polyols and ions (major ions and organic acids) and PAHs. In the same way emission samples taken at a motor test stand and at a test stand for wood combustion were analyzed (Schmidl et al. 2008). The saccharides were determined using high pH anion exchange and pulsed amperometry (HPAE-PAD). Details of the analytical method are given in Iinuma et al., 2009. Elemental and organic carbon were determined with a thermal-optical instrument (Sunset lab

  18. Chemical speciation and source apportionment of Non-Methane Volatile Organic Compounds (NMVOCs) in a Middle Eastern country

    Science.gov (United States)

    Salameh, Therese; Sauvage, Stéphane; Afif, Charbel; Borbon, Agnès; Locoge, Nadine

    2014-05-01

    NMVOCs, emitted from various sources, are of particular interest since they contribute to the formation of tropospheric ozone, PAN and secondary organic aerosols resulting in negative impacts on human health, climate and on the environment. To identify abatement measures, a profound knowledge of emission sources and their composition is a prerequisite. Air pollution in the Middle East region remains difficult to assess and understand because of a lack of ground-based measurements and the limited information on NMVOC chemical speciation and source apportionment. Based on a large database of NMVOC observations obtained in Beirut, the capital of Lebanon (a developing country in the Middle East region, located in Western Asia on the eastern shore of the Mediterranean Sea), the overall objective of this work is to apportion the sources of NMVOCs encountered in Lebanon. First, source profiles were determined with field measurements close to the main potential emitters namely the road transport, gasoline vapour, power generation and solvent uses. The results obtained are compared to other studies held in other regions and are used to assess the emission inventory developed for Lebanon. Secondly, two intensive field campaigns were held in a receptor site in Beirut during summer 2011 and winter 2012 in order to obtain a large time resolved dataset. The PMF analysis of this dataset was applied to apportion anthropogenic sources in this area. In both seasons, combustion (road transport and power generation) and gasoline evaporation, especially in winter, were the main sources contributing to the NMVOCs in Beirut. The results will support model implementation especially by completing the emission inventory established for the year 2010 by Waked et al. 2012 according to the EEA/EMEP guidelines because of the lack of Lebanon-specific emission factor.

  19. Characterization of PM2.5 in Guangzhou, China: uses of organic markers for supporting source apportionment.

    Science.gov (United States)

    Wang, Jingzhi; Ho, Steven Sai Hang; Ma, Shexia; Cao, Junji; Dai, Wenting; Liu, Suixin; Shen, Zhenxing; Huang, Rujin; Wang, Gehui; Han, Yongming

    2016-04-15

    Organic carbon (OC), elemental carbon (EC), and non-polar organic compounds including n-alkanes (n-C14-n-C40), polycyclic aromatic hydrocarbons (PAHs), phthalate esters (PAEs) and hopanes were quantified in fine particulate (PM2.5), which were collected in urban area of Guangzhou, China in winter and summer in 2012/2013. The pollutants levels were well comparable with the data obtained in previous studies in Pearl River Delta (PRD) region but much lower than most northern Chinese megacities. The contribution of EC to PM2.5 and OC/EC ratio suggest that the pollution sources were relatively consistent in GZ between the two seasons. Benzo[a]pyrene (BaP) was the most abundant PAHs, which were 4.9 and 1.0ng/m(3) on average, accounting for 10.7% and 9.1% to the total quantified PAHs in winter and summer, respectively. The total concentrations of PAEs ranged from 289.1 to 2435ng/m(3) and from 102.4 to 1437ng/m(3), respectively, in winter and summer. Di-n-butyl phthalate (DBP) was the most dominant PAEs. The ambient levels of PAEs could be partly attributed to the widespread uses of the household products, municipal garbage compressing, sewage, and external painting material on the building. Source apportionment for OC with chemical mass balance (CMB) model demonstrated coal combustion, vehicle emission, cooking, and secondary organic compounds (SOC) formation were the four major pollution sources. Both of the indices of n-alkanes and diagnostic PAHs ratios support that anthropogenic sources such as vehicle emission and coal combustion were the significant pollution sources with some extents from epicuticular waxes by terrestrial plants. The ratio of hopanes to EC proved the influences from vehicle emission, and displayed a certain degree of the air aging in the Guangzhou ambient air. PMID:26851882

  20. Characterization and source apportionment of health risks from ambient PM10 in Hong Kong over 2000-2011

    Science.gov (United States)

    Li, Zhiyuan; Yuan, Zibing; Li, Ying; Lau, Alexis K. H.; Louie, Peter K. K.

    2015-12-01

    Atmospheric particulate matter (PM) pollution is a major public health concern in Hong Kong. In this study, the spatiotemporal variations of health risks from ambient PM10 from seven air quality monitoring stations between 2000 and 2011 were analyzed. Positive matrix factorization (PMF) was adopted to identify major source categories of ambient PM10 and quantify their contributions. Afterwards, a point-estimated risk model was used to identify the inhalation cancer and non-cancer risks of PM10 sources. The long-term trends of the health risks from classified local and non-local sources were explored. Furthermore, the reason for the increase of health risks during high PM10 days was discussed. Results show that vehicle exhaust source was the dominant inhalation cancer risk (ICR) contributor (72%), whereas trace metals and vehicle exhaust sources contributed approximately 27% and 21% of PM10 inhalation non-cancer risk (INCR), respectively. The identified local sources accounted for approximately 80% of the ICR in Hong Kong, while contribution percentages of the non-local and local sources for INCR are comparable. The clear increase of ICR at high PM days was mainly attributed to the increase of contributions from coal combustion/biomass burning and secondary sulfate, while the increase of INCR at high PM days was attributed to the increase of contributions from the sources coal combustion/biomass burning, secondary nitrate, and trace metals. This study highlights the importance of health risk-based source apportionment in air quality management with protecting human health as the ultimate target.

  1. Back-trajectory-based source apportionment of airborne sulfur and nitrogen concentrations at Rocky Mountain National Park, Colorado, USA

    Science.gov (United States)

    Gebhart, Kristi A.; Schichtel, Bret A.; Malm, William C.; Barna, Michael G.; Rodriguez, Marco A.; Collett, Jeffrey L., Jr.

    2011-01-01

    The Rocky Mountain Atmospheric Nitrogen and Sulfur Study (RoMANS), conducted during the spring and summer of 2006, was designed to assess the sources of nitrogen and sulfur species that contribute to wet and dry deposition and visibility impairment at Rocky Mountain National Park (RMNP), Colorado. Several source apportionment methods were utilized for RoMANS, including the Trajectory Mass Balance (TrMB) Model, a receptor-based method in which the hourly measured concentrations are the dependent variables and the residence times of back trajectories in several source regions are the independent variables. The regression coefficients are estimates of the mean emissions, dispersion, chemical transformation, and deposition between the source areas and the receptors. For RoMANS, a new ensemble technique was employed in which input parameters were varied to explore the range, variability, and model sensitivity of source attribution results and statistical measures of model fit over thousands of trials for each set of concentration measurements. Results showed that carefully chosen source regions dramatically improved the ability of TrMB to reproduce temporal patterns in the measured concentrations, and source attribution results were also very sensitive to source region choices. Conversely, attributions were relatively insensitive to trajectory start height, trajectory length, minimum endpoints per source area, and maximum endpoint height, as long as the trajectories were long enough to reach contributing source areas and were not overly restricted in height or horizontal location. Source attribution results estimated that more than half the ammonia and 30-45% of sulfur dioxide and other nitrogen-containing species at the RoMANS core site were from sources within the state of Colorado. Approximately a quarter to a third of the sulfate was from within Colorado.

  2. Lanthanum and lanthanides in atmospheric fine particles and their apportionment to refinery and petrochemical operations in Houston, TX

    Science.gov (United States)

    Kulkarni, Pranav; Chellam, Shankararaman; Fraser, Matthew P.

    A study was conducted in Houston, TX focusing on rare earth elements (REEs) in atmospheric fine particles and their sources. PM 2.5 samples were collected from an ambient air quality monitoring site (HRM3) located in the proximity of a large number of oil refineries and petrochemical industries to estimate the potential contributions of emissions from fluidized-bed catalytic cracking operations to ambient fine particulate matter. The elemental composition of ambient PM 2.5, several commercially available zeolite catalysts, and local soil was measured after microwave assisted acid digestion using inductively coupled plasma—mass spectrometry. Source identification and apportionment was performed by principal component factor analysis (PCFA) in combination with multiple linear regression. REE relative abundance sequence, ratios of La to light REEs (Ce, Pr, Nd, and Sm), and enrichment factor analysis indicated that refining and petrochemical cat cracking operations were predominantly responsible for REE enrichment in ambient fine particles. PCFA yielded five physically meaningful PM 2.5 sources: cat cracking operations, a source predominantly comprised of crustal material, industrial high temperature operations, oil combustion, and sea spray. These five sources accounted for 82% of the total mass of atmospheric fine particles (less carbon and sulfate). Factor analysis confirmed that emissions from cat cracking operations primarily contributed to REE enrichment in PM 2.5 even though they comprised only 2.0% of the apportioned mass. Results from this study demonstrate the need to characterize catalysts employed in the vicinity of the sampling stations to accurately determine local sources of atmospheric REEs.

  3. Radiocarbon-based source apportionment of elemental carbon aerosols at two South Asian receptor observatories over a full annual cycle

    International Nuclear Information System (INIS)

    Black carbon (BC) aerosols impact climate and air quality. Since BC from fossil versus biomass combustion have different optical properties and different abilities to penetrate the lungs, it is important to better understand their relative contributions in strongly affected regions such as South Asia. This study reports the first year-round 14C-based source apportionment of elemental carbon (EC), the mass-based correspondent to BC, using as regional receptor sites the international Maldives Climate Observatory in Hanimaadhoo (MCOH) and the mountaintop observatory of the Indian Institute of Tropical Meteorology in Sinhagad, India (SINH). For the highly-polluted winter season (December–March), the fractional contribution to EC from biomass burning (fbio) was 53 ± 5% (n = 6) at MCOH and 56 ± 3% at SINH (n = 5). The fbio for the non-winter remainder was 53 ± 11% (n = 6) at MCOH and 48 ± 8% (n = 7) at SINH. This observation-based constraint on near-equal contributions from biomass burning and fossil fuel combustion at both sites compare with predictions from eight technology-based emission inventory (EI) models for India of (fbio)EI spanning 55–88%, suggesting that most current EI for Indian BC systematically under predict the relative contribution of fossil fuel combustion. A continued iterative testing of bottom-up EI with top-down observational source constraints has the potential to lead to reduced uncertainties regarding EC sources and emissions to the benefit of both models of climate and air quality as well as guide efficient policies to mitigate emissions. (letter)

  4. Submicron aerosol source apportionment of wintertime pollution in Paris, France by Double Positive Matrix Factorization (PMF2 using Aerosol Chemical Speciation Monitor (ACSM and multi-wavelength Aethalometer

    Directory of Open Access Journals (Sweden)

    J.-E. Petit

    2014-06-01

    Full Text Available Online non-refractory submicron Aerosol Mass Spectrometer (AMS measurements in urban areas have successfully allowed the apportionment of specific sources and/or physical and chemical properties of the organic fraction. However, in order to be fully representative of PM pollution, a comprehensive source apportionment analysis is needed by taking into account all major components of submicron aerosols, creating strengthened bonds between the organic components and pollution sources. We present here a novel two-step methodology to perform such an analysis, by taking advantage of high time resolution of monitoring instruments: the Aerosol Chemical Speciation Monitor (ACSM and the multi-wavelength absorption measurements (Aethalometer AE31 in Paris, France. As a first step, organic aerosols (OA were deconvoluted to hydrocarbon-like OA (HOA, Biomass Burning OA (BBOA and Oxygenated OA (OOA with Positive Matrix Factorization, and black carbon was deconvolved into its wood burning and fossil fuel combustion fractions. A second PMF analysis was then carried out with organic factors, BC fractions and inorganic species (nitrate, sulfate, ammonium, chloride, leading to a~four-factor solution allowing real-time characterization of the major sources of PM1. Outputs of this PMF2 include two dominant combustion sources (wood burning and traffic as well as semi-volatile and low-volatile secondary aerosols. While HOA is found to be emitted by both wood burning and traffic, the latter sources occurred to significantly contribute also to OOA.

  5. Source apportionment of PM10 and PM2.5 near a large mining zone in Northern Chile

    Science.gov (United States)

    Jorquera, H.

    2008-12-01

    Chile's economic growth is mainly driven by intensive mining activities; currently Chile produces ~ 40% of copper worldwide. Most of those activities are located in northern Chile, in a desert region where strong regional winds contribute with soil erosion as well. The city of Calama (22.4°S, 68.9°W) is about 17 km south of Chuquicamata, one of the largest open pit copper mines in the world, both located on the west edge of the Andes; Calama is at 2,400 m asl and it is 215 km east of the Pacific Ocean. The mining complex releases ~ 21 kton/y of PM10 and ~ 78 kton/y of SO2 from a copper smelter. The levels of ambient PM10 have steadily increased at Calama in the last 5 years, so there is concern about the impacts from copper industry in the city´s inhabitants, most of who work in mining or related economic activities. A campaign was conducted at Calama between October and December 2007, sampling ambient PM10 and PM2.5 at several sites across the city. Filters were analyzed at the Desert Research Institute, Reno, NV for elemental composition by XRF and for elemental and organic carbon using thermal analysis. The application of positive matrix factorization (PMF) model identified four sources contributing to ambient PM2.5: secondary sulfates (49%), traffic emissions (37%), dust street (9%) and copper smelter emissions (5%). In the coarse fraction, four sources were identified: dust street (45%), wind erosion (34%), mineral processing (14%) and copper smelter emissions (7%). No natural background was found for PM2.5. For ambient PM10 the source apportionment obtained is: mining activities (33%), street dust (34%), wind erosion (22%) and traffic emissions (12%). With a current PM10 annual average of 58 μg/m3 and further mining activities projected in the area, there is a big challenge to improve air quality in the populated area close to the mining operations.

  6. Development and evaluation of a daily temporal interpolation model for fine particulate matter species concentrations and source apportionment

    Science.gov (United States)

    Redman, Jeremiah D.; Holmes, Heather A.; Balachandran, Sivaraman; Maier, Marissa L.; Zhai, Xinxin; Ivey, Cesunica; Digby, Kyle; Mulholland, James A.; Russell, Armistead G.

    2016-09-01

    The impacts of emissions sources on air quality in St. Louis, Missouri are assessed for use in acute health effects studies. However, like many locations in the United States, the speciated particulate matter (PM) measurements from regulatory monitoring networks in St. Louis are only available every third day. The power of studies investigating acute health effects of air pollution is reduced when using one-in-three day source impacts compared to daily source impacts. This paper presents a temporal interpolation model to estimate daily speciated PM2.5 mass concentrations and source impact estimates using one-in-three day measurements. The model is used to interpolate 1-in-3 day source impact estimates and to interpolate the 1-in-3 day PM species concentrations prior to source apportionment (SA). Both approaches are compared and evaluated using two years (June 2001-May 2003) of daily data from the St. Louis Midwest Supersite (STL-SS). Data withholding is used to simulate a 1-in-3 day data set from the daily data to evaluate interpolated estimates. After evaluation using the STL-SS data, the model is used to estimate daily source impacts at another site approximately seven kilometers (7 km) northwest of the STL-SS (Blair); results between the sites are compared. For interpolated species concentrations, the model performs better for secondary species (sulfate, nitrate, ammonium, and organic carbon) than for primary species (metals and elemental carbon), likely due to the greater spatial autocorrelation of secondary species. Pearson correlation (R) values for sulfate, nitrate, ammonium, elemental carbon, and organic carbon ranged from 0.61 (elemental carbon, EC2) to 0.97 (sulfate). For trace metals, the R values ranged from 0.31 (Ba) to 0.81 (K). The interpolated source impact estimates also indicated a stronger correlation for secondary sources. Correlations of the secondary source impact estimates based on measurement data and interpolation data ranged from 0.68 to 0

  7. Chemical characteristics and source apportionment of PM2.5 during the harvest season in eastern China's agricultural regions

    Science.gov (United States)

    Li, Jianfeng; Song, Yu; Mao, Yi; Mao, Zhichun; Wu, Yusheng; Li, Mengmeng; Huang, Xin; He, Qichao; Hu, Min

    2014-08-01

    To determine the contribution of the open burning of wheat straw residues to local PM2.5 during the harvest season of June 2013, PM2.5 was sampled in an agricultural region in eastern China. The sampling site was approximately 1 km from the nearest wheat field. Chemical compositions were analyzed, and source apportionment was undertaken using the positive matrix factorization model. The average PM2.5 concentration was 110.7 μg/m3, containing 36.4 μg/m3 organics, 7.3 μg/m3 EC, 6.0 μg/m3 potassium (K) and 4.9 μg/m3 chloride ion (Cl-). The sampling period was divided into three phases: the pre-local-burning phase (Phase 1), the local-burning phase (Phase 2) and the post-local-burning phase (Phase 3). In Phase 2, the concentrations of PM2.5 and the organics, EC, K and Cl- in PM2.5 were 163.6 μg/m3, 59.0 μg/m3, 12.2 μg/m3, 11.0 μg/m3 and 10.8 μg/m3, respectively, which were all remarkably higher than in both Phase 1 and Phase 3. Eight sources of PM2.5 were determined, including two types of wheat residue burning sources, which showed a significant difference in Cl- content. The atmospheric relative humidity (RH) and the aging process of PM2.5 might be the causes: only fresh particulate emissions from wheat residue burning could feature high-concentration Cl- under high RH conditions. In Phase 2, wheat residue burning contributed 51.3% of PM2.5, 75.8% of OC, 74.5% of EC, 90.1% of K and 104.1% of Cl-. These percentages were lower in Phases 1 and 3 than in Phase 2. Wheat residue burning caused such severe air pollution that it's necessary to prohibit the open burning of crop residues in order to protect public health and the environment.

  8. Source apportionment of indoor, outdoor and personal PM2.5 exposure of pregnant women in Barcelona, Spain

    Science.gov (United States)

    Minguillón, M. C.; Schembari, A.; Triguero-Mas, M.; de Nazelle, A.; Dadvand, P.; Figueras, F.; Salvado, J. A.; Grimalt, J. O.; Nieuwenhuijsen, M.; Querol, X.

    2012-11-01

    Exposure to air pollution has been shown to adversely affect foetal development in the case of pregnant women. The present study aims to investigate the PM composition and sources influencing personal exposure of pregnant women in Barcelona. To this end, indoor, outdoor and personal exposure measurements were carried out for a selection of 54 pregnant women between November 2008 and November 2009. PM2.5 samples were collected during two consecutive days and then analysed for black smoke (BS), major and trace elements, and polycyclic aromatic hydrocarbons (PAHs) concentrations. Personal information such as commuting patterns and cosmetics use was also collected. PM2.5 concentrations were higher for personal samples than for indoor and outdoor environments. Indoor, outdoor and personal BS and sulphate concentrations were strongly correlated, although some specific indoor and outdoor sulphate sources may exist. Average trace elements concentrations were similar indoor, outdoor and for personal exposure, but the correlations were moderate for most of them. Most of the PAHs concentrations showed strong correlations indoor-outdoor. A source apportionment analysis of the PM composition data by means of a Positive Matrix Factorization (PMF) resulted in the identification of six sources for the outdoor and indoor environments: secondary sulphate, fueloil + sea salt (characterized by V, Ni, Na and Mg), mineral, cigarette (characterized by K, Ce, Cd, benzo(k)fluoranthene and benzo(ghi)perylene), road traffic (characterized by BS and low weight PAHs), and industrial (characterized by Pb, Sn, Cu, Mn and Fe). For personal exposure two specific sources were found: cosmetics (characterized by abundance of Ca, Li, Ti and Sr and the absence of Al) and train/subway (characterized by Fe, Mn, Cu and Ba). The contribution of the sources varied widely among women, especially for cigarette (from zero to up to 4 μg m-3), train/subway (up to more than 6 μg m-3) and cosmetics (up to more

  9. An inter-comparison of PM2.5 at urban and urban background sites: Chemical characterization and source apportionment

    Science.gov (United States)

    Cesari, D.; Donateo, A.; Conte, M.; Merico, E.; Giangreco, A.; Giangreco, F.; Contini, D.

    2016-06-01

    A measurement campaign was performed between 04/03/2013 and 17/07/2013 for simultaneous collection of PM2.5 samples in two nearby sites in southeastern Italy: an urban site and an urban background site. PM2.5 at the two sites were similar; however, the chemical composition and the contributions of the main sources were significantly different. The coefficients of divergence (CODs) showed spatial heterogeneity of EC (higher at the urban site because of traffic emissions) and of all metals. Major ions (NH4+, Na+, and SO42 -) and OC had low CODs, suggesting a homogeneous distribution of sea spray, secondary sulfate, and secondary organic matter (SOM = 1.6*OCsec, where OCsec is the secondary OC). The strong correlations between Na+ and Cl-, and the low Cl-/Na+ ratios, suggested the presence of aged sea spray with chloride depletion (about 79% of Cl-) and formation of sodium nitrate at both sites. In both sites, the non-sea-salt sulfate was about 97% of sulfate, and the strong correlation between SO42 - and NH4+ indicated that ammonium was present as ammonium sulfate. However, during advection of Saharan Dust, calcium sulfate was present rather than ammonium sulfate. The source apportionment was performed using the Positive Matrix Factorization comparing outputs of model EPA PMF 3.0 and 5.0 version. Six aerosol sources were identified at both sites: traffic, biomass burning, crustal-resuspended dust, secondary nitrate, marine aerosol, and secondary sulfate. The PMF3.0 model was not completely able, in these sites, to separate marine contribution from secondary nitrate and secondary sulfate from OC, underestimating the marine contribution and overestimating the secondary sulfate with respect to stoichiometric calculations. The application of specific constraints on PMF5.0 provided cleaner profiles, improving the comparison with stoichiometric calculations. The seasonal trends revealed larger biomass burning contributions during the cold period at both sites due to

  10. ACTRIS ACSM intercomparison – Part 2: Intercomparison of ME-2 organic source apportionment results from 15 individual, co-located aerosol mass spectrometers

    Directory of Open Access Journals (Sweden)

    R. Fröhlich

    2015-06-01

    Full Text Available Chemically resolved atmospheric aerosol data sets from the largest intercomparison of the Aerodyne aerosol chemical speciation monitors (ACSMs performed to date were collected at the French atmospheric supersite SIRTA. In total 13 quadrupole ACSMs (Q-ACSM from the European ACTRIS ACSM network, one time-of-flight ACSM (ToF-ACSM, and one high-resolution ToF aerosol mass spectrometer (AMS were operated in parallel for about 3 weeks in November and December~2013. Part 1 of this study reports on the accuracy and precision of the instruments for all the measured species. In this work we report on the intercomparison of organic components and the results from factor analysis source apportionment by positive matrix factorisation (PMF utilising the multilinear engine 2 (ME-2. Except for the organic contribution of mass-to-charge ratio m/z 44 to the total organics (f44, which varied by factors between 0.6 and 1.3 compared to the mean, the peaks in the organic mass spectra were similar among instruments. The m/z 44 differences in the spectra resulted in a variable f44 in the source profiles extracted by ME-2, but had only a minor influence on the extracted mass contributions of the sources. The presented source apportionment yielded four factors for all 15 instruments: hydrocarbon-like organic aerosol (HOA, cooking-related organic aerosol (COA, biomass burning-related organic aerosol (BBOA and secondary oxygenated organic aerosol (OOA. ME-2 boundary conditions (profile constraints were optimised individually by means of correlation to external data in order to achieve equivalent / comparable solutions for all ACSM instruments and the results are discussed together with the investigation of the influence of alternative anchors (reference profiles. A comparison of the ME-2 source apportionment output of all 15 instruments resulted in relative standard deviations (SD from the mean between 13.7 and 22.7 % of the source's average mass contribution depending on

  11. ACTRIS ACSM intercomparison – Part 2: Intercomparison of ME-2 organic source apportionment results from 15 individual, co-located aerosol mass spectrometers

    Directory of Open Access Journals (Sweden)

    R. Fröhlich

    2015-02-01

    Full Text Available Chemically resolved atmospheric aerosol data sets from the largest intercomparison of the Aerodyne aerosol chemical speciation monitors (ACSM performed to date were collected at the French atmospheric supersite SIRTA. In total 13 quadrupole ACSMs (Q-ACSM from the European ACTRIS ACSM network, one time-of-flight ACSM (ToF-ACSM, and one high-resolution ToF aerosol mass spectrometer (AMS were operated in parallel for about three weeks in November and December 2013. Part 1 of this study reports on the accuracy and precision of the instruments for all the measured species. In this work we report on the intercomparison of organic components and the results from factor analysis source apportionment by positive matrix factorisation (PMF utilising the multilinear engine 2 (ME-2. Except for the organic contribution of m/z 44 to the total organics (f44, which varied by factors between 0.6 and 1.3 compared to the mean, the peaks in the organic mass spectra were similar among instruments. The m/z 44 differences in the spectra resulted in a variable f44 in the source profiles extracted by ME-2, but had only a minor influence on the extracted mass contributions of the sources. The presented source apportionment yielded four factors for all 15 instruments: hydrocarbon-like organic aerosol (HOA, cooking-related organic aerosol (COA, biomass burning-related organic aerosol (BBOA and secondary oxygenated organic aerosol (OOA. Individual application and optimisation of the ME-2 boundary conditions (profile constraints are discussed together with the investigation of the influence of alternative anchors (reference profiles. A comparison of the ME-2 source apportionment output of all 15 instruments resulted in relative SD from the mean between 13.7 and 22.7% of the source's average mass contribution depending on the factors (HOA: 14.3 ± 2.2%, COA: 15.0 ± 3.4%, OOA: 41.5 ± 5.7%, BBOA: 29.3 ± 5.0%. Factors which tend to be subject to minor factor mixing (in this

  12. APORT: a program for the area-based apportionment of county variables to cells of a polar grid. [Airborne pollutant transport models

    Energy Technology Data Exchange (ETDEWEB)

    Fields, D.E.; Little, C.A.

    1978-11-01

    The APORT computer code was developed to apportion variables tabulated for polygon-structured civil districts onto cells of a polar grid. The apportionment is based on fractional overlap between the polygon and the grid cells. Centering the origin of the polar system at a pollutant source site yields results that are very useful for assessing and interpreting the effects of airborne pollutant dissemination. The APOPLT graphics code, which uses the same data set as APORT, provides a convenient visual display of the polygon structure and the extent of the polar grid. The APORT/APOPLT methodology was verified by application to county summaries of cattle population for counties surrounding the Oyster Creek, New Jersey, nuclear power plant. These numerical results, which were obtained using approximately 2-min computer time on an IBM System 360/91 computer, compare favorably to results of manual computations in both speed and accuracy.

  13. Levels and source apportionment of children's lead exposure: could urinary lead be used to identify the levels and sources of children's lead pollution?

    Science.gov (United States)

    Cao, Suzhen; Duan, Xiaoli; Zhao, Xiuge; Wang, Beibei; Ma, Jin; Fan, Delong; Sun, Chengye; He, Bin; Wei, Fusheng; Jiang, Guibin

    2015-04-01

    As a highly toxic heavy metal, the pollution and exposure risks of lead are of widespread concern for human health. However, the collection of blood samples for use as an indicator of lead pollution is not always feasible in most cohort or longitudinal studies, especially those involving children health. To evaluate the potential use of urinary lead as an indicator of exposure levels and source apportionment, accompanying with environmental media samples, lead concentrations and isotopic measurements (expressed as (207)Pb/(206)Pb, (208)Pb/(206)Pb and (204)Pb/(206)Pb) were investigated and compared between blood and urine from children living in the vicinities of a typical coking plant and lead-acid battery factory. The results showed urinary lead might not be a preferable proxy for estimating blood lead levels. Fortunately, urinary lead isotopic measurements could be used as an alternative for identifying the sources of children's lead exposure, which coincided well with the blood lead isotope ratio analysis. PMID:25617855

  14. Hybrid averaging offers high-flow contrast by cost apportionment among imaging time, axial, and lateral resolution in optical coherence tomography angiography.

    Science.gov (United States)

    Li, Peng; Cheng, Yuxuan; Li, Pei; Zhou, Liping; Ding, Zhihua; Ni, Yang; Pan, Cong

    2016-09-01

    The current temporal, wavelength, angular, and spatial averaging approaches trade imaging time and resolution for multiple independent measurements that improve the flow contrast in optical coherence tomography angiography (OCTA). We find that these averaging approaches are equivalent in principle, offering almost the same flow contrast enhancement as the number of averages increases. Based on this finding, we propose a hybrid averaging strategy for contrast enhancement by cost apportionment. We demonstrate that, compared with any individual approach, the hybrid averaging is able to offer a desired flow contrast without severe degradation of imaging time and resolution. Making use of the extended range of a VCSEL-based swept-source OCT, an angular averaging approach by path length encoding is also demonstrated for flow contrast enhancement. PMID:27607943

  15. Spatio-temporal patterns and source apportionment of pollution in Qiantang River (China) using neural-based modeling and multivariate statistical techniques

    Science.gov (United States)

    Su, Shiliang; Zhi, Junjun; Lou, Liping; Huang, Fang; Chen, Xia; Wu, Jiaping

    Characterizing the spatio-temporal patterns and apportioning the pollution sources of water bodies are important for the management and protection of water resources. The main objective of this study is to describe the dynamics of water quality and provide references for improving river pollution control practices. Comprehensive application of neural-based modeling and different multivariate methods was used to evaluate the spatio-temporal patterns and source apportionment of pollution in Qiantang River, China. Measurement data were obtained and pretreated for 13 variables from 41 monitoring sites for the period of 2001-2004. A self-organizing map classified the 41 monitoring sites into three groups (Group A, B and C), representing different pollution characteristics. Four significant parameters (dissolved oxygen, biochemical oxygen demand, total phosphorus and total lead) were identified by discriminant analysis for distinguishing variations of different years, with about 80% correct assignment for temporal variation. Rotated principal component analysis (PCA) identified four potential pollution sources for Group A (domestic sewage and agricultural pollution, industrial wastewater pollution, mineral weathering, vehicle exhaust and sand mining), five for Group B (heavy metal pollution, agricultural runoff, vehicle exhaust and sand mining, mineral weathering, chemical plants discharge) and another five for Group C (vehicle exhaust and sand mining, chemical plants discharge, soil weathering, biochemical pollution, mineral weathering). The identified potential pollution sources explained 75.6% of the total variances for Group A, 75.0% for Group B and 80.0% for Group C, respectively. Receptor-based source apportionment was applied to further estimate source contributions for each pollution variable in the three groups, which facilitated and supported the PCA results. These results could assist managers to develop optimal strategies and determine priorities for river

  16. An integrated SOM-based multivariate approach for spatio-temporal patterns identification and source apportionment of pollution in complex river network

    International Nuclear Information System (INIS)

    In this study, three classification techniques (self-organizing maps, hierarchical cluster analysis and discriminant analysis) were applied to identify spatial water pollution levels, temporal water quality response delay phenomena (WQRDP), source pollution types (point, urban non-point, or agricultural non-point). Two models (principal components analysis (PCA), and positive matrix factorization (PMF)) were used to do the further quantitative source apportionment studying. The 27 inflow rivers in spatial were divided into three pollution levels (A, high; B, medium; C, low). The primary pollution pattern in spatial Clusters A, B, and C were point, urban non-point and agricultural non-point separately, in consideration of simultaneous land use types. Source apportionment results identified five typical factors in spatial Cluster A and six typical factors in spatial Cluster B and C as responsible for the data structure, explaining 80%–90% of the total variance of the dataset. - Highlights: ► The nutrients pollution level in spatial Clusters A, B, and C were high, medium and low respectively. ► The WQRDP mainly caused by rivers internal pollution and surface detention. ► The non-point source pollution was a primary factor in the entire study watershed. ► Organic wastewater is the primary sources of pollution. ► NO3− pollution was prominent in spatial Cluster C. - Spatio-temporal combinational analysis provides a powerful mean to identify source pollution types and the non-point source pollution was a primary factor in the study watershed.

  17. Inter-comparison of source apportionment models for the estimation of wood burning aerosols during wintertime in an Alpine city (Grenoble, France

    Directory of Open Access Journals (Sweden)

    O. Favez

    2010-01-01

    Full Text Available The emission of organic aerosols (OA in the ambient air by residential wood burning is nowadays a subject of great scientific concern and a growing number of studies aim at apportioning the influence of such emissions on urban air quality. In the present study, results obtained using two commonly-used source apportionment models, i.e., Chemical Mass Balance (CMB, performed with off-line filter measurements and Positive Matrix Factorization (PMF, applied to aerosol mass spectrometer measurements, as well as using the recently-proposed aethalometer model (based on the measurement of the aerosol light absorption at different wavelengths are inter-compared. This work is performed using field data obtained during the winter season (14 to 30 January 2009 at an urban background site of a French Alpine city (Grenoble. Converging results from the different models indicate a major contribution of wood burning organic aerosols (OMwb to the organic fraction, with mean OMwb contributions to total OA of about 67%, 60% and 38% for the CMB, the aethalometer and the AMS-PMF models, respectively. Quantitative discrepancies might notably be due to the overestimation of OMwb calculated by the CMB due to the loss of semi-volatile compounds from sources to receptor site, as well as to the accounting of oxidized primary wood burning organic (OPOAwb aerosols within the Oxygenated Organic Aerosol (OOA PMF-factor. This OOA factor accounts on average for about 50% of total OM, while non-combustion sources contribute to about 25% and 28% of total OM according to the CMB and aethalometer models, respectively. Each model suggests a mean contribution of fossil fuel emissions to total OM of about 10%. A good agreement is also obtained for the source apportionment of elemental carbon (EC by both the CMB and aethalometer models, with fossil fuel emissions representing on average more than 80% of total EC.

  18. Source apportionment of VOCs and the contribution to photochemical ozone formation during summer in the typical industrial area in the Yangtze River Delta, China

    Science.gov (United States)

    Shao, Ping; An, Junlin; Xin, Jinyuan; Wu, Fangkun; Wang, Junxiu; Ji, Dongsheng; Wang, Yuesi

    2016-07-01

    Volatile organic compounds (VOCs) were continuously observated in a northern suburb of Nanjing, a typical industrial area in the Yangtze River Delta, in a summer observation period from 15th May to 31st August 2013. The average concentration of total VOCs was (34.40 ± 25.20) ppbv, including alkanes (14.98 ± 12.72) ppbv, alkenes (7.35 ± 5.93) ppbv, aromatics (9.06 ± 6.64) ppbv and alkynes (3.02 ± 2.01) ppbv, respectively. Source apportionment via Positive Matrix Factorization was conducted, and six major sources of VOCs were identified. The industry-related sources, including industrial emissions and industrial solvent usage, occupied the highest proportion, accounting for about 51.26% of the VOCs. Vehicular emissions occupied the second highest proportion, accounting for about 34.08%. The rest accounted for about 14.66%, including vegetation emission and liquefied petroleum gas/natural gas usage. Contributions of VOCs to photochemical O3 formation were evaluated by the application of a detailed chemical mechanism model (NCAR MM). Alkenes were the dominant contributors to the O3 photochemical production, followed by aromatics and alkanes. Alkynes had a very small impact on photochemical O3 formation. Based on the outcomes of the source apportionment, a sensitivity analysis of relative O3 reduction efficiency (RORE), under different source removal regimes such as using the reduction of VOCs from 10% to 100% as input, was conducted. The RORE was the highest (~ 20%-40%) when the VOCs from solvent-related sources decreased by 40%. The highest RORE values for vegetation emissions, industrial emissions, vehicle exhaust, and LPG/NG usage were presented in the scenarios of 50%, 80%, 40% and 40%, respectively.

  19. Size-resolved source apportionment of particulate matter in urban Beijing during haze and non-haze episodes

    Science.gov (United States)

    Tian, S. L.; Pan, Y. P.; Wang, Y. S.

    2016-01-01

    Additional size-resolved chemical information is needed before the physicochemical characteristics and sources of airborne particles can be understood; however, this information remains unavailable in most regions of China due to lacking measurement data. In this study, we report observations of various chemical species in size-segregated particle samples that were collected over 1 year in the urban area of Beijing, a megacity that experiences severe haze episodes. In addition to fine particles, high concentrations of coarse particles were measured during the periods of haze. The abundance and chemical compositions of the particles in this study were temporally and spatially variable, with major contributions from organic matter and secondary inorganic aerosols. The contributions of organic matter to the particle mass decreased from 37.9 to 31.2 %, and the total contribution of sulfate, nitrate and ammonium increased from 19.1 to 33.9 % between non-haze and haze days, respectively. Due to heterogeneous reactions and hygroscopic growth, the peak concentrations of the organic carbon, cadmium and sulfate, nitrate, ammonium, chloride and potassium shifted from 0.43 to 0.65 µm on non-haze days to 0.65-1.1 µm on haze days. Although the size distributions of lead and thallium were similar during the observation period, their concentrations increased by a factor of more than 1.5 on haze days compared with non-haze days. We observed that sulfate and ammonium, which have a size range of 0.43-0.65 µm, sulfate and nitrate, which have a size range of 0.65-1.1 µm, calcium, which has a size range of 5.8-9 µm, and the meteorological factors of relative humidity and wind speed were responsible for haze pollution when the visibility was less than 10 km. Source apportionment using Positive Matrix Factorization showed six PM2.1 sources and seven PM2.1-9 common sources: secondary inorganic aerosol (25.1 % for fine particles vs. 9.8 % for coarse particles), coal combustion (17

  20. Size-resolved source apportionment of particulate matter in urban Beijing during haze and non-haze episodes

    Science.gov (United States)

    Tian, S. L.; Pan, Y. P.; Wang, Y. S.

    2015-03-01

    More size-resolved chemical information is needed before the physicochemical characteristics and sources of airborne particles can be understood, but this information remains unavailable in most regions of China due to a paucity of measurement data. In this study, we report a one-year observation of various chemical species in size-segregated particle samples collected in urban Beijing, a mega city that experiences severe haze episodes. In addition to fine particles, the measured particle size distributions showed high concentrations of coarse particles during the haze periods. The abundance and chemical compositions of the particles in this study were temporally and spatially variable, with major contributions from organic matter and secondary inorganic aerosols. The contribution of the organic matter to the mass decreased from 37.9 to 33.1%, whereas the total contribution of SO42-, NO3- and NH4+ increased from 19.1 to 32.3% on non-haze and haze days, respectively. Due to heterogeneous reactions and hygroscopic growth, the peaks in the size distributions of organic carbon, SO42-, NO3-, NH4+, Cl-, K+ and Cu shifted from 0.43-0.65 μm on non-haze days to 0.65-1.1 μm on haze days. Although the size distributions are similar for the heavy metals Pb, Cd and Tl during the observation period, their concentrations increased by a factor of more than 1.5 on haze days compared with non-haze days. We found that NH4+ with a size range of 0.43-0.65 μm, SO42- and NO3- with a size range of 0.65-1.1 μm and Ca2+ with a size range of 5.8-9 μm as well as the meteorological factors of relative humidity and wind speed were responsible for the haze pollution when the visibility was less than 15 km. Source apportionment using positive matrix factorization identified six common sources: secondary inorganic aerosols (26.1% for fine particles vs. 9.5% for coarse particles), coal combustion (19 vs. 23.6%), primary emissions from vehicles (5.9 vs. 8.0%), biomass burning (8.5 vs. 2

  1. Source apportionment of submicron organic aerosol at an urban background and a road site in Barcelona (Spain during SAPUSS

    Directory of Open Access Journals (Sweden)

    M. Alier

    2013-10-01

    Full Text Available This study investigates the contribution of potential sources to the submicron (PM1 organic aerosol (OA simultaneously detected at an urban background (UB and a road site (RS in Barcelona during the 30 days of the intensive field campaign of SAPUSS (Solving Aerosol Problems by Using Synergistic Strategies, September–October 2010. A total of 103 filters at 12 h sampling time resolution were collected at both sites. Thirty-six neutral and polar organic compounds of known emission sources and photo-chemical transformation processes were analyzed by gas chromatography–mass spectrometry (GC-MS. The concentrations of the trace chemical compounds analyzed are herein presented and discussed. Additionally, OA source apportionment was performed by multivariate curve resolution–alternating least squares (MCR-ALS and six OA components were identified at both sites: two were of primary anthropogenic OA origin and three of secondary OA origin, while a sixth one was not clearly defined. Primary organics from emissions of local anthropogenic activities (urban primary organic aerosol, or POA Urban, mainly traffic emissions but also cigarette smoke, contributed 43% (1.5 μg OC m−3 and 18% (0.4 μg OC m−3 to OA at RS and UB, respectively. A secondary primary source – biomass burning (BBOA – was found in all the samples (average values 7% RS; 12% UB; 0.3 μg OC m−3, but this component was substantially contributing to OA only when the sampling sites were under influence of regional air mass circulation (REG.. Three secondary organic aerosol (SOA components (describing overall 60% of the variance were observed in the urban ambient PM1. Products of isoprene oxidation (SOA ISO – i.e. 2-methylglyceric acid, C5 alkene triols and 2-methyltetrols – showed the highest abundance at both sites when the city was under influence of inland air masses. The overall concentrations of SOA ISO were similar at both sites (0.4 and 0.3 μg m−3, or 16% and 7%, at

  2. The AIRPARIF-AEROSOL project: A comprehensive source apportionment study of fine aerosols (PM2.5) in the region of Paris (France)

    Science.gov (United States)

    Sciare, Jean; Ghersi, Veronique; Bressi, Michael; Lameloise, Philippe; Bonnaire, Nicolas; Rosso, Amandine; Nicolas, Jose; Moukhtar, Sophie; Ferron, Anais; Baumier, Dominique

    2010-05-01

    With a population of about 12 millions inhabitants (20% of the French population), Greater Paris (France) is one of the most populated megacity in Europe and among the few located in developed countries. Due to its favorable geographical situation (far from other big European cities and influenced very often by clean oceanic air masses), it may be considered as a good candidate for investigating the build-up of urban air pollution from temperate industrialized countries. Particulate mass of fine aerosols with aerodynamic diameter below 2.5μm (PM2.5) is continuously monitored at several stations from great Paris for almost 8 years by the local air quality network (AIRPARIF), using a conventional on-line automatic system (R&P TEOM; see Patashnik and Rupprecht, 1991). During the period 2000-2006, levels of PM2.5 in the region of Paris have shown rather stable yearly mean values ranging 13 to 16?g/m3 whereas most of the other pollutants monitored by AIRPARIF have shown a net decrease during this period (http:\\www.airparif.asso.fr). Since the year 2007, this situation has becoming worse for particulate pollution with a net increase of the yearly mean concentration of PM2.5 (up to 21?g/m3), which increase is partly due to the use of a new PM2.5 measurement technique (R&P TEOM-FDMS instrument) enabling a proper determination of the semi-volatile fraction of fine aerosols. Although this new method greatly improves the determination of PM2.5, it has also brought PM2.5 levels in the region of Paris closer to the 25?g/m3 yearly mean targeted value recommended by Europe for 2010 (limit value for 2015). Efficient abatement policies aiming at reducing levels of PM2.5 in the region of Paris will have to be fed by preliminary PM2.5 source apportionment studies and exhaustive aerosol chemistry studies (chemical mass balance) allowing a better separation between regional to continental aerosol sources. The objective of the AIRPARIF-AEROSOL project aims to perform a spatially- and

  3. Simultaneous monitoring and compositions analysis of PM1 and PM2.5 in Shanghai: Implications for characterization of haze pollution and source apportionment.

    Science.gov (United States)

    Qiao, Ting; Zhao, Mengfei; Xiu, Guangli; Yu, Jianzhen

    2016-07-01

    A year-long simultaneous observation of PM1 and PM2.5 were conducted at ECUST campus in Shanghai, the compositions were analyzed and compared. Results showed that PM2.5 was dominated by PM1 on clear days while the contribution of PM1-2.5 to PM2.5 increased on haze days, indicating that PM2.5 should be given priority to characterize or predict haze pollution. On haze days, accumulation of organic carbon (OC), elemental carbon (EC) and primary organic carbon (POC) in PM1-2.5 was faster than that in PM1. Humic-like substances carbon (Hulis-C) in both PM2.5 and PM1 formed faster than water soluble organic carbon (WSOC) on haze days, hence Hulis-C/WSOC increased with the intensification of haze pollution. In terms of water soluble ions, NO3(-)/SO4(2-) in PM1 increased with the aggravation of haze pollution, implying that mobile sources dominated on haze days, so is nitrogen oxidation ratio (NOR). Liquid water content (LWC) in both PM1 and PM2.5 had positive correlations with relative humidity (RH) but negative correlations with visibility, implying that hygroscopic growth might be a factor for visibility impairment, especially LWC in PM1. By comparison with multi-linear equations of LWC in PM1 and PM2.5, NO3(-) exerted a higher influence on hygroscopicity of PM1 than PM2.5, while RH, WSOC, SO4(2-) and NH4(+) had higher effects on PM2.5, especially WSOC. Source apportionment of PM2.5 was also investigated to provide reference for policy making. Cluster analysis by HYSPLIT (HYbrid Single Particle Lagrangian Integrated Trajectory) model showed that PM2.5 originated from marine aerosols, middle-scale transportation and large-scale transportation. Furthermore, PM2.5 on haze days was dominated by middle-scale transportation. In line with source apportionment by positive matrix factorization (PMF) model, PM2.5 was attributed to secondary inorganics, aged sea salt, combustion emissions, hygroscopic growth and secondary organics. Secondary formation was the principle source of

  4. Source Apportionment of PM2.5 using PMF and CMB: Comparison of the Effects of Transboundary and Local Pollutions in the Western Japan

    Science.gov (United States)

    Iijima, A.; Sugata, S.

    2014-12-01

    PM2.5 has become one of the most important aspects in recent air pollution issues. In Japan, the achievement rate of the environmental quality standard for PM2.5 is in a worse situation so far (43.3% for ambient air monitoring station, 33.3% for roadside air pollution monitoring station in FY2012). Therefore, source apportionment will be essential to policy and decision making for improving the PM2.5 pollution. Since 2011, we started the field monitoring study called "Current Status Elucidation and Source Contribution Assessment of PM2.5 Pollution in Collaboration with Environmental Research Institutes across Japan" which was granted by the Environment Research and Technology Development Fund (5B-1101) of the Ministry of the Environment, Japan. PM2.5 samples were collected at 14 sites during four campaigns. Chemical analyses of carbonaceous compounds, ionic species, and elements were conducted. Source apportionment was performed by using Positive Matrix Factorization (PMF, EPA PMF 3.0) and Chemical Mass Balance (CMB, EPA CMB 8.1) models. PMF model resolved a six-factor solution. Each of these factors has a distinctive grouping of species that can be associated with a specific source sector (F1: Biomass burning, F2: Sulfate + Oil combustion, F3: Industry, F4: Nitrate, F5: Sulfate + Coal combustion, and F6: Chloride). In the winter campaign (Jan. 24 to Feb. 7) in 2013, F5 accounted for 50% of total PM2.5 mass at Tsushima (34.2°N 129.3°E, the westernmost remote site). The contribution of F5 tended to decrease toward the eastern sites (27% at Fukuoka (33.5°N 130.5°E, urban site), 22% at Higashi-Osaka (34.7°N 135.6°E, urban site)). CMB model showed similar results in the same campaign. Coal combustion accounted for 49%, 30%, and 22% of total PM2.5 mass at Tsushima, Fukuoka, and Higashi-Osaka, respectively (Fig.1). On the other hand, at urban sites, higher contributions from local sources such as secondary nitrate (16% at Fukuoka, 21% at Higashi-Osaka), diesel fuel

  5. Simultaneous monitoring and compositions analysis of PM1 and PM2.5 in Shanghai: Implications for characterization of haze pollution and source apportionment.

    Science.gov (United States)

    Qiao, Ting; Zhao, Mengfei; Xiu, Guangli; Yu, Jianzhen

    2016-07-01

    A year-long simultaneous observation of PM1 and PM2.5 were conducted at ECUST campus in Shanghai, the compositions were analyzed and compared. Results showed that PM2.5 was dominated by PM1 on clear days while the contribution of PM1-2.5 to PM2.5 increased on haze days, indicating that PM2.5 should be given priority to characterize or predict haze pollution. On haze days, accumulation of organic carbon (OC), elemental carbon (EC) and primary organic carbon (POC) in PM1-2.5 was faster than that in PM1. Humic-like substances carbon (Hulis-C) in both PM2.5 and PM1 formed faster than water soluble organic carbon (WSOC) on haze days, hence Hulis-C/WSOC increased with the intensification of haze pollution. In terms of water soluble ions, NO3(-)/SO4(2-) in PM1 increased with the aggravation of haze pollution, implying that mobile sources dominated on haze days, so is nitrogen oxidation ratio (NOR). Liquid water content (LWC) in both PM1 and PM2.5 had positive correlations with relative humidity (RH) but negative correlations with visibility, implying that hygroscopic growth might be a factor for visibility impairment, especially LWC in PM1. By comparison with multi-linear equations of LWC in PM1 and PM2.5, NO3(-) exerted a higher influence on hygroscopicity of PM1 than PM2.5, while RH, WSOC, SO4(2-) and NH4(+) had higher effects on PM2.5, especially WSOC. Source apportionment of PM2.5 was also investigated to provide reference for policy making. Cluster analysis by HYSPLIT (HYbrid Single Particle Lagrangian Integrated Trajectory) model showed that PM2.5 originated from marine aerosols, middle-scale transportation and large-scale transportation. Furthermore, PM2.5 on haze days was dominated by middle-scale transportation. In line with source apportionment by positive matrix factorization (PMF) model, PM2.5 was attributed to secondary inorganics, aged sea salt, combustion emissions, hygroscopic growth and secondary organics. Secondary formation was the principle source of

  6. Inter-comparison of source apportionment models for the estimation of wood burning aerosols during wintertime in an Alpine city (Grenoble, France

    Directory of Open Access Journals (Sweden)

    O. Favez

    2010-06-01

    Full Text Available The emission of organic aerosols (OA in the ambient air by residential wood burning is nowadays a subject of great scientific concern and a growing number of studies aim at apportioning the influence of such emissions on urban air quality. In the present study, results obtained using two commonly-used source apportionment models, i.e., Chemical Mass Balance (CMB, performed with off-line filter measurements and Positive Matrix Factorization (PMF, applied to Aerosol Mass Spectrometer measurements, as well as using the recently-proposed Aethalometer model (based on the measurement of the aerosol light absorption at different wavelengths are inter-compared. This work is performed using field data obtained during the winter season (14 to 29 January 2009 at an urban background site of a French Alpine city (Grenoble. Converging results from the different models indicate a major contribution of wood burning organic aerosols (OMwb to the ambient aerosol organic fraction, with mean OMwb contributions to total OA of 68%, 61% and 37% for the CMB, the Aethalometer and the AMS-PMF models respectively, during the period when the three modelling studies overlapped (12 days. Quantitative discrepancies might notably be due to the overestimation of OMwb calculated by the CMB due to the loss of semi-volatile compounds from sources to receptor site, as well as to the accounting of oxidized primary wood burning organic (OPOAwb aerosols within the Oxygenated Organic Aerosol (OOA PMF-factor. This OOA factor accounts on average for about 50% of total OM, while non-combustion sources contribute to about 25% and 28% of total OM according to the CMB and Aethalometer models respectively. Each model suggests a mean contribution of fossil fuel emissions to total OM of about 10%. A good agreement is also obtained for the source apportionment of elemental carbon (EC by both the CMB and the Aethalometer models, with fossil fuel

  7. Chemical mass balance source apportionment of PM10 and TSP in residential and industrial sites of an urban region of Kolkata, India.

    Science.gov (United States)

    Gupta, A K; Karar, Kakoli; Srivastava, Anjali

    2007-04-01

    Daily average PM(10) (particulate matter which passes through a size selective impactor inlet with a 50% efficiency cut-off at 10 microm aerodynamic diameter), TSP (total suspended particulate matter) and their chemical species mass concentrations were measured at residential and industrial sites of an urban region of Kolkata during November 2003-November 2004. Source apportionment using chemical mass balance model revealed that the most dominant source throughout the study period at residential site was coal combustion (42%), while vehicular emission (47%) dominates at industrial site to PM(10). Paved road, field burning and wood combustion contributed 21%, 7% and 1% at residential site, while coal combustion, metal industry and soil dust contributed 34%, 1% and 1% at industrial site, respectively, to PM(10) during the study period. The contributors to TSP included coal combustion (37%), soil dust (19%), road dust (17%) and diesel combustion (15%) at residential site, while soil dust (36%), coal combustion (17%), solid waste (17%), road dust (16%) and tyre wear (7%) at industrial site. Significant seasonal variations of the particulate matters have been observed during the study period. In the monitoring sites total carbon, organic carbon and iron were found to be the marker species of road dust, while organic carbon, total carbon, chloride and sulfate have been observed as the marker species of soil dust in TSP. PMID:16987605

  8. Century-long source apportionment of PAHs in Athabasca oil sands region lakes using diagnostic ratios and compound-specific carbon isotope signatures.

    Science.gov (United States)

    Jautzy, Josué; Ahad, Jason M E; Gobeil, Charles; Savard, Martine M

    2013-06-18

    Evaluating the impact that airborne contamination associated with Athabasca oil sands (AOS) mining operations has on the surrounding boreal forest ecosystem requires a rigorous approach to source discrimination. This study presents a century-long historical record of source apportionment of polycyclic aromatic hydrocarbons (PAHs) in dated sediments from two headwater lakes located approximately 40 and 55 km east from the main area of open pit mining activities. Concentrations of the 16 Environmental Protection Agency (EPA) priority PAHs in addition to retene, dibenzothiophene (DBT), and six alkylated groups were measured, and both PAH molecular diagnostic ratios and carbon isotopic signatures (δ(13)C) of individual PAHs were used to differentiate natural from anthropogenic inputs. Although concentrations of PAHs in these lakes were low and below the Canadian Council of Ministers of the Environment (CCME) guidelines, diagnostic ratios pointed to an increasingly larger input of petroleum-derived (i.e., petrogenic) PAHs over the past 30 years concomitant with δ(13)C values progressively shifting to the value of unprocessed AOS bitumen. This petrogenic source is attributed to the deposition of bitumen in dust particles associated with wind erosion from open pit mines.

  9. Source apportionment and dynamic changes of carbonaceous aerosols during the haze bloom-decay process in China based on radiocarbon and organic molecular tracers

    Science.gov (United States)

    Liu, Junwen; Li, Jun; Liu, Di; Ding, Ping; Shen, Chengde; Mo, Yangzhi; Wang, Xinming; Luo, Chunling; Cheng, Zhineng; Szidat, Sönke; Zhang, Yanlin; Chen, Yingjun; Zhang, Gan

    2016-03-01

    Fine carbonaceous aerosols (CAs) is the key factor influencing the currently filthy air in megacities in China, yet few studies simultaneously focus on the origins of different CAs species using specific and powerful source tracers. Here, we present a detailed source apportionment for various CAs fractions, including organic carbon (OC), water-soluble OC (WSOC), water-insoluble OC (WIOC), elemental carbon (EC) and secondary OC (SOC) in the largest cities of North (Beijing, BJ) and South China (Guangzhou, GZ), using the measurements of radiocarbon and anhydrosugars. Results show that non-fossil fuel sources such as biomass burning and biogenic emission make a significant contribution to the total CAs in Chinese megacities: 56 ± 4 in BJ and 46 ± 5 % in GZ, respectively. The relative contributions of primary fossil carbon from coal and liquid petroleum combustions, primary non-fossil carbon and secondary organic carbon (SOC) to total carbon are 19, 28 and 54 % in BJ, and 40, 15 and 46 % in GZ, respectively. Non-fossil fuel sources account for 52 in BJ and 71 % in GZ of SOC, respectively. These results suggest that biomass burning has a greater influence on regional particulate air pollution in North China than in South China. We observed an unabridged haze bloom-decay process in South China, which illustrates that both primary and secondary matter from fossil sources played a key role in the blooming phase of the pollution episode, while haze phase is predominantly driven by fossil-derived secondary organic matter and nitrate.

  10. Source apportionment of methane and nitrous oxide in California's San Joaquin Valley at CalNex 2010 via positive matrix factorization

    Directory of Open Access Journals (Sweden)

    A. Guha

    2015-03-01

    Full Text Available Sources of methane (CH4 and nitrous oxide (N2O were investigated using measurements from a site in southeast Bakersfield as part of the CalNex (California at the Nexus of Air Quality and Climate Change experiment from 15 May to 30 June 2010. Typical daily minimum mixing ratios of CH4 and N2O were higher than daily averages that were simultaneously observed at a similar latitude background station (NOAA, Mauna Loa by approximately 70 and 0.5 ppb, respectively. Substantial enhancements of CH4 and N2O (hourly averages > 500 ppb and > 7 ppb, respectively were routinely observed suggesting the presence of large regional sources. Collocated measurements of carbon monoxide (CO and a range of volatile organic compounds (VOCs (e.g. straight-chain and branched alkanes, cycloalkanes, chlorinated alkanes, aromatics, alcohols, isoprene, terpenes and ketones were used with a Positive Matrix Factorization (PMF source apportionment method to estimate the contribution of regional sources to observed enhancements of CH4 and N2O. The PMF technique provided a "top-down" deconstruction of ambient gas-phase observations into broad source categories, yielding a 7-factor solution. We identified these source factors as emissions from evaporative and fugitive; motor vehicles; livestock and dairy; agricultural and soil management; daytime light and temperature driven; non-vehicular urban; and nighttime terpene biogenics and anthropogenics. The dairy and livestock factor accounted for a majority of the CH4 (70–90% enhancements during the duration of the experiments. Propagation of uncertainties in the PMF-derived factor profiles and time series from bootstrapping analysis resulted in a 29% uncertainty in the CH4 apportionment to this factor. The dairy and livestock factor was also a principal contributor to the daily enhancements of N2O (60–70% with an uncertainty of 33%. Agriculture and soil management accounted for ~20–25% of N2O enhancements over the course of a

  11. Long-term measurements of particle number size distributions and the relationships with air mass history and source apportionment in the summer of Beijing

    Science.gov (United States)

    Wang, Z. B.; Hu, M.; Wu, Z. J.; Yue, D. L.; He, L. Y.; Huang, X. F.; Liu, X. G.; Wiedensohler, A.

    2013-10-01

    A series of long-term and temporary measurements were conducted to study the improvement of air quality in Beijing during the Olympic Games period (8-24 August 2008). To evaluate actions taken to improve the air quality, comparisons of particle number and volume size distributions of August 2008 and 2004-2007 were performed. The total particle number and volume concentrations were 14 000 cm-3 and 37 μm-3 cm-3 in August of 2008, respectively. These were reductions of 41% and 35% compared with mean values of August 2004-2007. A cluster analysis on air mass history and source apportionment were performed, exploring reasons for the reduction of particle concentrations. Back trajectories were classified into five major clusters. Air masses from the south direction are always associated with pollution events during the summertime in Beijing. In August 2008, the frequency of air mass arriving from the south was 1.3 times higher compared to the average of the previous years, which however did not result in elevated particle volume concentrations in Beijing. Therefore, the reduced particle number and volume concentrations during the 2008 Beijing Olympic Games cannot be only explained by meteorological conditions. Four factors were found influencing particle concentrations using a positive matrix factorization (PMF) model. They were identified as local and remote traffic emissions, combustion sources as well as secondary transformation. The reductions of the four sources were calculated to 47%, 44%, 43% and 30%, respectively. The significant reductions of particle number and volume concentrations may attribute to actions taken, focusing on primary emissions, especially related to the traffic and combustion sources.

  12. Water quality assessment and apportionment of pollution sources using APCS-MLR and PMF receptor modeling techniques in three major rivers of South Florida.

    Science.gov (United States)

    Haji Gholizadeh, Mohammad; Melesse, Assefa M; Reddi, Lakshmi

    2016-10-01

    In this study, principal component analysis (PCA), factor analysis (FA), and the absolute principal component score-multiple linear regression (APCS-MLR) receptor modeling technique were used to assess the water quality and identify and quantify the potential pollution sources affecting the water quality of three major rivers of South Florida. For this purpose, 15years (2000-2014) dataset of 12 water quality variables covering 16 monitoring stations, and approximately 35,000 observations was used. The PCA/FA method identified five and four potential pollution sources in wet and dry seasons, respectively, and the effective mechanisms, rules and causes were explained. The APCS-MLR apportioned their contributions to each water quality variable. Results showed that the point source pollution discharges from anthropogenic factors due to the discharge of agriculture waste and domestic and industrial wastewater were the major sources of river water contamination. Also, the studied variables were categorized into three groups of nutrients (total kjeldahl nitrogen, total phosphorus, total phosphate, and ammonia-N), water murkiness conducive parameters (total suspended solids, turbidity, and chlorophyll-a), and salt ions (magnesium, chloride, and sodium), and average contributions of different potential pollution sources to these categories were considered separately. The data matrix was also subjected to PMF receptor model using the EPA PMF-5.0 program and the two-way model described was performed for the PMF analyses. Comparison of the obtained results of PMF and APCS-MLR models showed that there were some significant differences in estimated contribution for each potential pollution source, especially in the wet season. Eventually, it was concluded that the APCS-MLR receptor modeling approach appears to be more physically plausible for the current study. It is believed that the results of apportionment could be very useful to the local authorities for the control and

  13. Mexico City aerosol analysis during MILAGRO using high resolution aerosol mass spectrometry at the urban supersite (T0) - Part 1: Fine particle composition and organic source apportionment

    Energy Technology Data Exchange (ETDEWEB)

    Aiken, A.C.; Wang, J.; Salcedo, D.; Cubison, M. J.; Huffman, J. A.; DeCarlo, P. F.; Ulbrich, I. M.; Docherty, K. S.; Sueper, D.; Kimmel, J. R.; Worsnop, D. R.; Trimborn, A.; Northway, M.; Stone, E. A.; Schauer, J. J.; Volkamer, R. M.; Fortner, E.; de Foy, B.; Laskin, A.; Shutthanandan, V.; Zheng, J.; Zhang, R.; Gaffney, J.; Marley, N. A.; Paredes-Miranda, G.; Arnott, W. P.; Molina, L. T.; Sosa, G.; Jimenez, J. L.

    2009-09-01

    Submicron aerosol was analyzed during the MILAGRO field campaign in March 2006 at the T0 urban supersite in Mexico City with a High-Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS) and complementary instrumentation. Mass concentrations, diurnal cycles, and size distributions of inorganic and organic species are similar to results from the CENICA supersite in April 2003 with organic aerosol (OA) comprising about half of the fine PM mass. Positive Matrix Factorization (PMF) analysis of the high resolution OA spectra identified three major components: chemically-reduced urban primary emissions (hydrocarbon-like OA, HOA), oxygenated OA (OOA, mostly secondary OA or SOA), and biomass burning OA (BBOA) that correlates with levoglucosan and acetonitrile. BBOA includes several very large plumes from regional fires and likely also some refuse burning. A fourth OA component is a small local nitrogen-containing reduced OA component (LOA) which accounts for 9% of the OA mass but one third of the organic nitrogen, likely as amines. OOA accounts for almost half of the OA on average, consistent with previous observations. OA apportionment results from PMF-AMS are compared to the PM{sub 2.5} chemical mass balance of organic molecular markers (CMB-OMM, from GC/MS analysis of filters). Results from both methods are overall consistent. Both assign the major components of OA to primary urban, biomass burning/woodsmoke, and secondary sources at similar magnitudes. The 2006 Mexico City emissions inventory underestimates the urban primary PM{sub 2.5} emissions by a factor of {approx}4, and it is {approx}16 times lower than afternoon concentrations when secondary species are included. Additionally, the forest fire contribution is at least an order-of-magnitude larger than in the inventory.

  14. Source apportionment by PMF on elemental concentrations obtained by PIXE analysis of PM10 samples collected at the vicinity of lignite power plants and mines in Megalopolis, Greece

    Energy Technology Data Exchange (ETDEWEB)

    Manousakas, M. [Department of Chemistry, University of Patras, 26500 Patras, Achaia (Greece); E.R.L., Institute of Nuclear & Radiological Sciences & Technology, Energy & Safety, N.C.S.R. Demokritos, 15310 Ag. Paraskevi, Attiki (Greece); Diapouli, E. [E.R.L., Institute of Nuclear & Radiological Sciences & Technology, Energy & Safety, N.C.S.R. Demokritos, 15310 Ag. Paraskevi, Attiki (Greece); Papaefthymiou, H. [Department of Chemistry, University of Patras, 26500 Patras, Achaia (Greece); Migliori, A.; Karydas, A.G.; Padilla-Alvarez, R.; Bogovac, M.; Kaiser, R.B. [Nuclear Science and Instrumentation Laboratory (NSIL), International Atomic Energy Agency, 2400 Seibersdorf (Austria); Jaksic, M.; Bogdanovic-Radovic, I. [Ruder Boskovic Institute, Bijenicka 54, P.O. Box 180, 10002 Zagreb (Croatia); Eleftheriadis, K. [E.R.L., Institute of Nuclear & Radiological Sciences & Technology, Energy & Safety, N.C.S.R. Demokritos, 15310 Ag. Paraskevi, Attiki (Greece)

    2015-04-15

    Particulate matter (PM) is an important constituent of atmospheric pollution especially in areas under the influence of industrial emissions. Megalopolis is a small city of 10,000 inhabitants located in central Peloponnese in close proximity to three coal opencast mines and two lignite fired power plants. 50 PM{sub 10} samples were collected in Megalopolis during the years 2009–11 for elemental and multivariate analysis. For the elemental analysis PIXE was used as one of the most effective techniques in APM analytical characterization. Altogether, the concentrations of 22 elements (Z = 11–33), whereas Black Carbon was also determined for each sample using a reflectometer. Factorization software was used (EPA PMF 3.0) for source apportionment analysis. The analysis revealed that major emission sources were soil dust 33% (7.94 ± 0.27 μg/m{sup 3}), biomass burning 19% (4.43 ± 0.27 μg/m{sup 3}), road dust 15% (3.63 ± 0.37 μg/m{sup 3}), power plant emissions 13% (3.01 ± 0.44 μg/m{sup 3}), traffic 12% (2.82 ± 0.37 μg/m{sup 3}), and sea spray 8% (1.99 ± 0.41 μg/m{sup 3}). Wind trajectories have suggested that metals associated with emission from the power plants came mainly from west and were connected with the locations of the lignite mines located in this area. Soil resuspension, road dust and power plant emissions increased during the warm season of the year, while traffic/secondary, sea spray and biomass burning become dominant during the cold season.

  15. Determination and analysis of PM 10 source apportionment during episodes of air pollution in Central Eastern European urban areas: The case of wintertime 2006

    Science.gov (United States)

    Juda-Rezler, Katarzyna; Reizer, Magdalena; Oudinet, Jean-Paul

    2011-11-01

    Source apportionment of air pollution due to particulate matter with an aerodynamic diameter Russia-Belarus-Ukraine), most were also under LRT from Southern origin (Slovakia, Czech Republic), and northern cities were under national RT influence. PCA analysis shows that ion-sums of secondary inorganic aerosols account for LRT pollution while arsenic and chromium represents markers of RT (industrial) and LP (residential) sources of PM 10, respectively. Determination of several ratios (REG/UB, REG/TRAF, TRAF/UB) calculated between PM 10 levels measured at regional background (REG); urban background (UB) and traffic (TRAF) monitoring sites shows that, with ratios REG/UB ≥ 0.57, PM 10 episodes in both Szczecin and Warsaw bore a marked RT origin. The lower REG/UB ≤ 0.35 in the Southern cities of Cracow and Zabrze indicates that LP was the main contributor to the observed episodes. Only PM 10 episodes in Southern-western Poland (Jelenia Góra) were clearly of LP origin as characterized, by the lowest REG/UB ratio (<0.2). The high TRAF/UB ratios obtained for all cities (close to 1) indicate that there was a great uniformity of PM levels on an urban scale owing to the meteorologically stagnant conditions. A high correlation between PM 10, NO 2 and CO confirms that traffic emission represented a common and an important LP source of urban pollution in most Polish cities during January 2006. On the other hand PM 10 which is also highly correlated with SO 2 in 4 cities out of 6, indicates that coal combustion through domestic heating or industrial activities was also an important LP source of PM 10. Finally, extremely unfavourable meteorological conditions caused by the influence of a Siberian high-pressure system were found to be associated with the occurrence of severe PM 10 episodes of pollution.

  16. Elemental quantification, chemistry, and source apportionment in golf course facilities in semi-arid urban landscape using portable x-ray fluorescence spectrometer

    Directory of Open Access Journals (Sweden)

    T. K. Udeigwe

    2015-01-01

    Full Text Available This study extends the application of the portable x-ray fluorescence (PXRF spectrometry to examination of elements in semi-arid urban landscapes of the Southern High Plains (SHP of the United States (US, focusing on golf courses. The complex environmental challenges of this region and the unique management practices at golf course facilities could lead to differences in concentration and chemistry of elements between managed (irrigated and non-managed (non-irrigated portions of these facilities. Soil samples were collected at the depths of 0–10, 10–20, and 20–30 cm from managed and non-managed areas of seven different facilities in the city of Lubbock, Texas, and analyzed for a suite of soil properties. Total elemental quantification was conducted using PXRF. Findings mostly indicated no significant differences in concentration of examined elements between the managed and non-managed areas of the facilities. However, strong positive relationships (R2 = 0.82–0.91, p < 0.001 were observed among elements (e.g. Fe and each of Cr, Mn, Ni, and As; Cu and Zn; As and Cr and between these elements and soil constituents or properties such as clay, calcium carbonate, organic matter, and pH. The strengths of these relationships were mostly higher in the non-managed areas, suggesting possible alteration in the chemistry of these elements by anthropogenic influences. Principal component analyses (PCA and correlation analyses within the managed areas suggested that As, Cr, Fe, Mn, and Ni could be of lithogenic origin, while Cu, Pb, and Zn were attributed to anthropogenic influences. Only one possible source of element, likely lithogenic, was identified within non-managed areas. As evidenced from the study, the PXRF can be a valuable tool for elemental quantification, and rapid investigation of elemental interaction and source apportionment in semi-arid climates.

  17. Lead isotopes combined with a sequential extraction procedure for source apportionment in the dry deposition of Asian dust and non-Asian dust.

    Science.gov (United States)

    Lee, Pyeong-Koo; Yu, Soonyoung

    2016-03-01

    Lead isotopic compositions were determined in leachates that were generated using sequential extractions of dry deposition samples of Asian dust (AD) and non-Asian dust (NAD) and Chinese desert soils, and used to apportion Pb sources. Results showed significant differences in (206)Pb/(207)Pb and (206)Pb/(204)Pb isotopic compositions in non-residual fractions between the dry deposition samples and the Chinese desert soils while (206)Pb/(207)Pb and (206)Pb/(204)Pb isotopic compositions in residual fraction of the dry deposition of AD and NAD were similar to the mean (206)Pb/(207)Pb and (206)Pb/(204)Pb in residual fraction of the Alashan Plateau soil. These results indicate that the geogenic materials of the dry deposition of AD and NAD were largely influenced by the Alashan Plateau soil, while the secondary sources of the dry deposition were different from those of the Chinese desert soils. In particular, the lead isotopic compositions in non-residual fractions of the dry deposition were homogenous, which implies that the non-residual four fractions (F1 to F4) shared the primary anthropogenic origin. (206)Pb/(207)Pb values and the predominant wind directions in the study area suggested that airborne particulates of heavily industrialized Chinese cities were one of the main Pb sources. Source apportionment calculations showed that the average proportion of anthropogenic Pb in the dry deposition of AD and NAD was 87% and 95% respectively in total Pb extraction, 92% and 97% in non-residual fractions, 15% and 49% in residual fraction. Approximately 81% and 80% of the anthropogenic Pb was contributed by coal combustion in China in the dry deposition of AD and NAD respectively while the remainder was derived from industrial Pb contamination. The research result proposes that sequential extractions with Pb isotope analysis are a useful tool for the discrimination of anthropogenic and geogenic origins in highly contaminated AD and NAD. PMID:26708760

  18. Seasonal and spatial variation of trace elements in multi-size airborne particulate matters of Beijing, China: Mass concentration, enrichment characteristics, source apportionment, chemical speciation and bioavailability

    Science.gov (United States)

    Gao, Jiajia; Tian, Hezhong; Cheng, Ke; Lu, Long; Wang, Yuxuan; Wu, Ye; Zhu, Chuanyong; Liu, Kaiyun; Zhou, Junrui; Liu, Xingang; Chen, Jing; Hao, Jiming

    2014-12-01

    The seasonal and spatial variation characteristics of 19 elements (Al, As, Be, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, S, Sb, Se, Zn) in TSP/PM10/PM2.5 samples were investigated, which were collected from April 2011 to January 2012 simultaneously at an urban downtown site, a traffic roadside site, a suburban site, and a rural site in Beijing. The elevated concentrations of several toxic trace elements (As, Cd, Mn, Ni, Pb, etc.) in particles revealed that the contamination of toxic elements in Beijing could not be neglected. Positive matrix factorization method (PMF) was applied for source apportionment of trace elements in PM, and three factors (crust related sources, combustion sources, and traffic and steel industrial related sources) were identified. Furthermore, the chemical speciation and bioavailability of various elements were identified by applying European Community Bureau of Reference (BCR) procedure. Our results showed that eight toxic elements (As, Cd, Cr, Cu, Ni, Pb, Sb and Zn) exhibited higher mobility in PM2.5 than in PM10. Notably, elements of As, Cd, Pb and Zn were presented with higher mobility than the other elements, and these elements were lightly to release into the environment and easily available to human body. Additionally, As, Cd, Pb and Zn also accounted for higher percentages in the bound to mobile fractions at the central urban areas of Beijing. Therefore, special concerns should be paid to these toxic trace elements which had relatively high mobility in fine particles, when planning and implementing the comprehensive air pollution mitigation policies in Beijing.

  19. Source apportionment and dynamic changes of carbonaceous aerosols during the haze bloom–decay process in China based on radiocarbon and organic molecular tracers

    Directory of Open Access Journals (Sweden)

    J. Liu

    2015-12-01

    Full Text Available Fine carbonaceous aerosols (CAs is the key factor influencing the currently filthy air in megacities of China, yet seldom study simultaneously focuses on the origins of different CAs species using specific and powerful source tracers. Here, we present a detailed source apportionment for various CAs fractions, including organic carbon (OC, water-soluble OC (WSOC, water-insoluble OC (WIOC, elemental carbon (EC and secondary OC (SOC in the largest cities of North (Beijing, BJ and South China (Guangzhou, GZ, respectively, using the measurements of radiocarbon and anhydrosugars. Results show that non-fossil fuel sources such as biomass burning and biogenic emission make a significant contribution to the total CAs in Chinese megacities: 56 ± 4 % in BJ and 46 ± 5 % in GZ, respectively. The relative contributions of primary fossil carbon from coal and liquid petroleum combustions, primary non-fossil carbon and secondary organic carbon (SOC to total carbon are 19, 28 and 54 % in BJ, and 40, 15 and 46 % in GZ, respectively. Non-fossil fuel sources account for 52 % in BJ and 71 % in GZ of SOC, respectively. These results suggest that biomass burning has a greater influence on regional particulate air pollution in North China than in South China. We observed an unabridged haze bloom–decay process in South China, which illustrates that both primary and secondary matter from fossil sources played a key role in the blooming phase of the pollution episode, while haze phase is predominantly driven by fossil-derived secondary organic matter and nitrate.

  20. Long-term measurements of particle number size distributions and the relationships with air mass history and source apportionment in the summer of Beijing

    Directory of Open Access Journals (Sweden)

    Z. B. Wang

    2013-10-01

    Full Text Available A series of long-term and temporary measurements were conducted to study the improvement of air quality in Beijing during the Olympic Games period (8–24 August 2008. To evaluate actions taken to improve the air quality, comparisons of particle number and volume size distributions of August 2008 and 2004–2007 were performed. The total particle number and volume concentrations were 14 000 cm−3 and 37 μm−3 cm−3 in August of 2008, respectively. These were reductions of 41% and 35% compared with mean values of August 2004–2007. A cluster analysis on air mass history and source apportionment were performed, exploring reasons for the reduction of particle concentrations. Back trajectories were classified into five major clusters. Air masses from the south direction are always associated with pollution events during the summertime in Beijing. In August 2008, the frequency of air mass arriving from the south was 1.3 times higher compared to the average of the previous years, which however did not result in elevated particle volume concentrations in Beijing. Therefore, the reduced particle number and volume concentrations during the 2008 Beijing Olympic Games cannot be only explained by meteorological conditions. Four factors were found influencing particle concentrations using a positive matrix factorization (PMF model. They were identified as local and remote traffic emissions, combustion sources as well as secondary transformation. The reductions of the four sources were calculated to 47%, 44%, 43% and 30%, respectively. The significant reductions of particle number and volume concentrations may attribute to actions taken, focusing on primary emissions, especially related to the traffic and combustion sources.

  1. Long-term measurements of particle number size distributions and the relationships with air mass history and source apportionment in the summer of Beijing

    Directory of Open Access Journals (Sweden)

    Z. B. Wang

    2013-02-01

    Full Text Available A series of long-term and temporary measurements were conducted to study the improvement of air quality in Beijing during Olympic Games period (8–24 August 2008. To evaluate actions taken to improve the air quality, comparisons of particle number and volume size distributions of August 2008 and 2004–2007 were performed. The total particle number and volume concentrations were 14 000 cm−3 and 37 μm3 cm−3 in August of 2008, respectively. These were reductions of 41% and 35% compared with the mean values of August 2004–2007. A cluster analysis on air mass history and source apportionment were performed, exploring reasons of the reduction of particle concentrations. Back trajectories were classified into five major clusters. Air mass from south direction are always associated with pollution events during the summertime of Beijing. In August 2008, the frequency of air mass arriving from south has been twice higher compared to the average of the previous years, these southerly air masses did however not result in elevated particle volume concentrations in Beijing. This result implied that the air mass history was not the key factor, explaining reduced particle number and volume concentrations during the Beijing 2008 Olympic Games. Four factors were found influencing particle concentrations using a Positive matrix factorization (PMF model. They were identified to local and remote traffic emissions, combustion sources as well as secondary transformation. The reductions of the four sources were calculated to 47%, 44%, 43% and 30%, respectively. The significant reductions of particle number and volume concentrations may attribute to actions taken, focusing on primary emissions, especially related to the traffic and combustion sources.

  2. Source Resolution and Risk Apportionment of Air Emission Sources in AN Industrial Complex for Risk Reduction Considerations: AN Air Waste Management Methodology.

    Science.gov (United States)

    Mukerjee, Shaibal

    The purpose of this study was to develop an air waste management methodology for apportioning the health risks associated with air emission source categories that are identified in a given airshed. This was implemented by expanding the receptor model technique to assess the non-carcinogenic and carcinogenic inhalation risks to an exposed population for certain element pollutants determined to be coming from specific emission sources. The concept was demonstrated using air quality data from a mid-sized industrial complex located in a rural/residential area. It was demonstrated that risks from identified, major elemental emission categories can be quantified and that a total, additive risk be determined for main source categories in the airshed. Potential risk reduction measures were targeted at main risk sources without arbitrarily reducing risk for all sources in the airshed thereby making it a cost-effective approach. Dispersion modeling was utilized from previous emission inventory data so that risk estimates for these sources could be modeled at other receptor points in the airshed. The factor analytic procedure for Source Resolution in the initial receptor modeling approach was used to show whether the ambient data fitted a Maximum-Likelihood Factor Analysis or Principal Component Analysis for identifying underlying emission sources. It was also shown how Maximum -Likelihood Factor Analysis can be a stronger source resolution procedure as opposed to Principal Component Analysis since Factor Analysis is metrically invariant. Finally, the use of the ambient air data for total particulates was used to expand the Source Resolution and Risk Apportionment concepts to augment the Bubble Policy currently used in Air Quality Management.

  3. Sources of methane and nitrous oxide in California's Central Valley estimated through direct airborne flux and positive matrix factorization source apportionment of groundbased and regional tall tower measurements

    Science.gov (United States)

    Guha, Abhinav

    Methane (CH4) and nitrous oxide (N2O) are two major greenhouse gases that contribute significantly to the increase in anthropogenic radiative-forcing causing perturbations to the earth's climate system. In a watershed moment in the state's history of environmental leadership and commitment, California, in 2006, opted for sharp reductions in their greenhouse gas (GHG) emissions and adopted a long-term approach to address climate change that includes regulation of emissions from individual emitters and source categories. There are large CH4 and N2O emissions sources in the state, predominantly in the agricultural and waste management sector. While these two gases account for Transects) study. Next, a one-year continuous field campaign (WGC 2012-13, June 2012 - August 2013) was conducted at the Walnut Grove tall tower near the Sacramento-San Joaquin River Delta in the Central Valley. Through analysis of these field measurements, this dissertation presents the apportionment of observed CH4 and N2O concentration enhancements into major source categories along with direct emissions estimates from airborne observations. We perform high-precision measurements of greenhouse gases using gas analyzers based on absorption spectroscopy, and other source marker volatile organic compounds (VOCs) using state of the art VOC measurement systems (e.g. proton transfer reaction mass spectrometry). We combine these measurements with a statistical source apportionment technique called positive matrix factorization (PMF) to evaluate and investigate the major local sources of CH4 and N2O during CalNex and Walnut Grove campaigns. In the CABERNET study, we combine measurements with an airborne approach to a well-established micrometeorological technique (eddy-covariance method) to derive CH4 fluxes over different source regions in the Central Valley. In the CalNex experiments, we demonstrate that dairy and livestock remains the largest source sector of non-CO2 greenhouse gases in the San

  4. 基于泥沙指纹识别的小流域颗粒态磷来源解析%Particulate phosphorus sources apportionment in small watershed based on sediment fingerprinting

    Institute of Scientific and Technical Information of China (English)

    周慧平; 常维娜; 张龙江

    2015-01-01

    Sediment control has attracted more attention in watershed management planning, especially for the transport of contaminants and nutrients (such as phosphorus (P)) by fine sediment. Implementation of specific management solutions for a watershed requires understanding the location and nature of the major sediment sources. Composite fingerprinting techniques have been proved as an effective mean of sediment source apportionment in other countries. However, research using this method is not reported for small watersheds that are relative homogeneity in underlying surface, or have lower sediment load output and more human disturbance. As for nutrients, particulate P adsorbed by fine sediment is the major part of P output in an agricultural watershed. Therefore, successful sediment source apportionment would give an access to P source identification and quantitative apportionment study. The objectives of this paper were to identify the sources of particulate P in a small catchment of the upper Jiuxiang River in Nanjing, and to estimate the relative contributions of the potential sources based on sediment source fingerprinting. A total of 56 surface samples from potential sediment sources were collected, including 20 from woodland, 21 from cultivated land, and 15 from mine areas and roads of transportation. In addition to suspended sediment collection, 17 deposited sediment samples were collected in the mainstream near catchment outlet. Twenty three potential fingerprint properties were selected for laboratory analysis with all samples screened to < 63μm. Composite fingerprints were acquired by a two-stage statistical fingerprinting procedure and a multivariate mixing model was used to estimate the contributions of potential sediment sources. A goodness of fit model was used to test the performance of the multivariate mixing model. The particulate P source apportionment was then proceeded based on the sediment fingerprinting results and P content information from all

  5. Reactive oxygen species associated with water-soluble PM2.5 in the southeastern United States: spatiotemporal trends and source apportionment

    Directory of Open Access Journals (Sweden)

    V. Verma

    2014-07-01

    Full Text Available We assess the potential of the water-soluble fraction of atmospheric fine aerosols in the southeastern US to generate reactive oxygen species (ROS and identify major ROS-associated emission sources. ROS-generation potential of particles was quantified by the dithiothreitol (DTT assay and involved analysis of fine particulate matter (PM extracted from high-volume quartz filters (23 h integrated samples collected at various sites in different environmental settings in the southeast, including three urban Atlanta sites, in addition to a rural site. Paired sampling was conducted with one fixed site in Atlanta (Jefferson Street, representative of the urban environment, with the others rotating among different sites, for ~250 days between June 2012 and September 2013 (N = 483. A simple linear regression between the DTT activity and aerosol chemical components revealed strong associations between PM ROS generation potential and secondary organic aerosol (WSOC in summer, and biomass burning markers in winter. Redox-active metals were also correlated with the DTT activity, but mostly at urban and roadside sites. Positive matrix factorization (PMF was applied to apportion the relative contribution of various sources to the ROS generation potential of water-soluble PM2.5 in urban Atlanta. PMF showed that vehicular emissions contribute uniformly throughout the year (12 to 25%, while secondary oxidation processes dominated the DTT activity in summer (46% and biomass burning in winter (47%. Mineral dust was significant only during drier periods (~12% in summer and fall. Source apportionment by chemical mass balance (CMB was reasonably consistent with PMF, but with higher contribution from vehicular emissions (32%. Given the spatially large data set of PM sampled over an extended period, the study reconciles the results from previous work that showed only region- or season-specific aerosol components or sources contributing to PM ROS activity, possibly due to

  6. Source apportionment of PM10 and PM(2.5) at Tocopilla, Chile (22 degrees 05' S, 70 degrees 12' W).

    Science.gov (United States)

    Jorquera, Héctor

    2009-06-01

    Tocopilla is located on the coast of Northern Chile, within an arid region that extends from 30 degrees S to the border with Perú. The major industrial activities are related to the copper mining industry. A measurement campaign was conducted during March and April 2006 to determine ambient PM10 and PM(2.5) concentrations in the city. The results showed significantly higher PM10 concentrations in the southern part of the city (117 microg/m3) compared with 79 and 80 (microg/m3) in the central and northern sites. By contrast, ambient PM2.5 concentrations had a more uniform spatial distribution across the city, around 20 (microg/m3). In order to conduct a source apportionment, daily PM10 and PM(2.5) samples were analyzed for elements by XRF. EPA's Positive Matrix Factorization software was used to interpret the results of the chemical compositions. The major source contributing to PM(2.5) at sites 1, 2 and 3, respectively are: (a) sulfates, with approximately 50% of PM2.5 concentrations at the three sites; (b) fugitive emissions from fertilizer storage and handling, with 16%, 21% and 10%; (c) Coal and residual oil combustion, with 15%, 15% and 4%; (d) Sea salt, 5%, 6% and 16%; (e) Copper ore processing, 4%, 5% and 15%; and (f) a mixed dust source with 11%, 7% and 4%. Results for PM10--at sites 1, 2 and 3, respectively--show that the major contributors are: (a) sea salt source with 36%, 32% and 36% of the PM10 concentration; (b) copper processing emissions mixed with airborne soil dust with 6.6%, 11.5% and 41%; (c) sulfates with 31%, 31% and 12%; (d) a mixed dust source with 16%, 12% and 10%, and (e) the fertilizer stockpile emissions, with 11%, 14% and 2% of the PM10 concentration. The high natural background of PM10 implies that major reductions in anthropogenic emissions of PM10 and SO2 would be required to attain ambient air quality standards for PM10; those reductions would curb down ambient PM(2.5) concentrations as well. PMID:18512124

  7. Concentration profiles, source apportionment and risk assessment of polycyclic aromatic hydrocarbons (PAHs) in dumpsite soils from Agbogbloshie e-waste dismantling site, Accra, Ghana.

    Science.gov (United States)

    Daso, Adegbenro P; Akortia, Eric; Okonkwo, Jonathan O

    2016-06-01

    methodological approaches for PAH source apportionment, including the use of molecular diagnostic ratios, mostly implicated pyrogenic processes as the main sources of PAHs into the investigated dumpsite soils. Furthermore, their compositional profiles across the sampling sites also suggest similar sources of PAHs into the dumpsite soil.

  8. Concentration profiles, source apportionment and risk assessment of polycyclic aromatic hydrocarbons (PAHs) in dumpsite soils from Agbogbloshie e-waste dismantling site, Accra, Ghana.

    Science.gov (United States)

    Daso, Adegbenro P; Akortia, Eric; Okonkwo, Jonathan O

    2016-06-01

    methodological approaches for PAH source apportionment, including the use of molecular diagnostic ratios, mostly implicated pyrogenic processes as the main sources of PAHs into the investigated dumpsite soils. Furthermore, their compositional profiles across the sampling sites also suggest similar sources of PAHs into the dumpsite soil. PMID:26897583

  9. Regional air quality in Leipzig, Germany: detailed source apportionment of size-resolved aerosol particles and comparison with the year 2000.

    Science.gov (United States)

    van Pinxteren, D; Fomba, K W; Spindler, G; Müller, K; Poulain, L; Iinuma, Y; Löschau, G; Hausmann, A; Herrmann, H

    2016-07-18

    A detailed source apportionment of size-resolved aerosol particles in the area of Leipzig, Germany, was performed. Sampling took place at four sites (traffic, traffic/residential, urban background, regional background) in parallel during summer 2013 and the winters 2013/14/15. Twenty-one samples were taken per season with a 5-stage Berner impactor and analysed for particulate mass, inorganic ions, organic and elemental carbon, water-soluble organic carbon, trace metals, and a wide range of organic species. The compositional data were used to estimate source contributions to particulate matter (PM) in quasi-ultrafine (up to 140 nm), accumulation mode, and coarse size ranges using Positive Matrix Factorisation (PMF) receptor modelling. Traffic (exhaust and general traffic emissions), coal combustion, biomass combustion, photochemistry, general secondary formation, cooking, fungal spores, urban dust, fresh sea/road salt, and aged sea salt were all found to contribute to different extents to observed PM concentrations. PMF derived estimates agreed reasonably with estimates from established macrotracer approaches. Quasi-ultrafine PM originated mainly from traffic (20-50%) and photochemistry (30-50%) in summer, while it was dominated by solid fuel (mainly biomass) combustion in winter (50-70%). Tentatively identified cooking aerosol contributed up to 36% on average at the residential site. For accumulation mode particles, two secondary sources typically contributed 40-90% to particle mass. In winter, biomass and coal combustion contributions were up to ca. 25% and 45%, respectively. Main sources of coarse particles were diverse and included nearly all PMF-resolved ones depending on season and air mass origin. For PM10, traffic (typically 20-40% at kerbside sites), secondary formation (30-60%), biomass combustion (10-15% in winter), and coal combustion (30-40% in winter with eastern air mass inflow) were the main quantified sources. At the residential site, contributions

  10. Source apportionment of methane and nitrous oxide in California's San Joaquin Valley at CalNex 2010 via positive matrix factorization

    Science.gov (United States)

    Guha, A.; Gentner, D. R.; Weber, R. J.; Provencal, R.; Goldstein, A. H.

    2015-10-01

    Sources of methane (CH4) and nitrous oxide (N2O) were investigated using measurements from a site in southeast Bakersfield as part of the CalNex (California at the Nexus of Air Quality and Climate Change) experiment from mid-May to the end of June 2010. Typical daily minimum mixing ratios of CH4 and N2O were higher than daily minima that were simultaneously observed at a mid-oceanic background station (NOAA, Mauna Loa) by approximately 70 ppb and 0.5 ppb, respectively. Substantial enhancements of CH4 and N2O (hourly averages > 500 and > 7 ppb, respectively) were routinely observed, suggesting the presence of large regional sources. Collocated measurements of carbon monoxide (CO) and a range of volatile organic compounds (VOCs) (e.g., straight-chain and branched alkanes, cycloalkanes, chlorinated alkanes, aromatics, alcohols, isoprene, terpenes and ketones) were used with a positive matrix factorization (PMF) source apportionment method to estimate the contribution of regional sources to observed enhancements of CH4 and N2O. The PMF technique provided a "top-down" deconstruction of ambient gas-phase observations into broad source categories, yielding a seven-factor solution. We identified these emission source factors as follows: evaporative and fugitive; motor vehicles; livestock and dairy; agricultural and soil management; daytime light and temperature driven; non-vehicular urban; and nighttime terpene biogenics and anthropogenics. The dairy and livestock factor accounted for the majority of the CH4 (70-90 %) enhancements during the duration of experiments. The dairy and livestock factor was also a principal contributor to the daily enhancements of N2O (60-70 %). Agriculture and soil management accounted for ~ 20-25 % of N2O enhancements over a 24 h cycle, which is not surprising given that organic and synthetic fertilizers are known to be a major source of N2O. The N2O attribution to the agriculture and soil management factor had a high uncertainty in the

  11. Accuracy and precision of 14C-based source apportionment of organic and elemental carbon in aerosols using the Swiss_4S protocol

    Directory of Open Access Journals (Sweden)

    G. O. Mouteva

    2015-04-01

    Full Text Available Aerosol source apportionment remains a critical challenge for understanding the transport and aging of aerosols, as well as for developing successful air pollution mitigation strategies. The contributions of fossil and non-fossil sources to organic carbon (OC and elemental carbon (EC in carbonaceous aerosols can be quantified by measuring the radiocarbon (14C content of each carbon fraction. However, the use of 14C in studying OC and EC has been limited by technical challenges related to the physical separation of the two fractions and small sample sizes. There is no common procedure for OC/EC 14C analysis, and uncertainty studies have largely focused on the precision of yields. Here, we quantified the uncertainty in 14C measurement of aerosols associated with the isolation and analysis of each carbon fraction with the Swiss_4S thermal-optical analysis (TOA protocol. We used an OC/EC analyzer (Sunset Laboratory Inc., OR, USA coupled to vacuum line to separate the two components. Each fraction was thermally desorbed and converted to carbon dioxide (CO2 in pure oxygen (O2. On average 91% of the evolving CO2 was then cryogenically trapped on the vacuum line, reduced to filamentous graphite, and measured for its 14C content via accelerator mass spectrometry (AMS. To test the accuracy of our set-up, we quantified the total amount of extraneous carbon introduced during the TOA sample processing and graphitization as the sum of modern and fossil (14C-depleted carbon introduced during the analysis of fossil reference materials (adipic acid for OC and coal for EC and contemporary standards (oxalic acid for OC and rice char for EC as a function of sample size. We further tested our methodology by analyzing five ambient airborne particulate matter (PM2.5 samples with a range of OC and EC concentrations and 14C contents in an interlaboratory comparison. The total modern and fossil carbon blanks of our set-up were 0.8 ± 0.4 and 0.67 ± 0.34 μg C

  12. Accuracy and precision of 14C-based source apportionment of organic and elemental carbon in aerosols using the Swiss_4S protocol

    Science.gov (United States)

    Mouteva, G. O.; Fahrni, S. M.; Santos, G. M.; Randerson, J. T.; Zhang, Y.-L.; Szidat, S.; Czimczik, C. I.

    2015-09-01

    Aerosol source apportionment remains a critical challenge for understanding the transport and aging of aerosols, as well as for developing successful air pollution mitigation strategies. The contributions of fossil and non-fossil sources to organic carbon (OC) and elemental carbon (EC) in carbonaceous aerosols can be quantified by measuring the radiocarbon (14C) content of each carbon fraction. However, the use of 14C in studying OC and EC has been limited by technical challenges related to the physical separation of the two fractions and small sample sizes. There is no common procedure for OC/EC 14C analysis, and uncertainty studies have largely focused on the precision of yields. Here, we quantified the uncertainty in 14C measurement of aerosols associated with the isolation and analysis of each carbon fraction with the Swiss_4S thermal-optical analysis (TOA) protocol. We used an OC/EC analyzer (Sunset Laboratory Inc., OR, USA) coupled to a vacuum line to separate the two components. Each fraction was thermally desorbed and converted to carbon dioxide (CO2) in pure oxygen (O2). On average, 91 % of the evolving CO2 was then cryogenically trapped on the vacuum line, reduced to filamentous graphite, and measured for its 14C content via accelerator mass spectrometry (AMS). To test the accuracy of our setup, we quantified the total amount of extraneous carbon introduced during the TOA sample processing and graphitization as the sum of modern and fossil (14C-depleted) carbon introduced during the analysis of fossil reference materials (adipic acid for OC and coal for EC) and contemporary standards (oxalic acid for OC and rice char for EC) as a function of sample size. We further tested our methodology by analyzing five ambient airborne particulate matter (PM2.5) samples with a range of OC and EC concentrations and 14C contents in an interlaboratory comparison. The total modern and fossil carbon blanks of our setup were 0.8 ± 0.4 and 0.67 ± 0.34 μg C, respectively

  13. 碳同位素技术在碳质气溶胶源解析中应用的研究进展%The Use of Carbon Isotope Analysis in Source Apportionment of Carbonaceous Aerosols: A Review

    Institute of Scientific and Technical Information of China (English)

    张世春; 王毅勇; 童全松

    2013-01-01

    概述了国内外14C和13C技术在大气碳质气溶胶源解析中应用的研究进展,指出14C在碳质气溶胶源解析研究中具有不可替代的独特优势,联合采用14C和13C技术有利于解决多种排放源的区分问题;随着碳质气溶胶组分分离技术的进步,对有机碳(0C)和黑碳(BC)等组分中14C的研究获得重要进展;除需深入研究13C的分馏机制外,建立各种排放源在不同区域的δ13C值域“特征谱”的重要性也日益突出;结合14C和13C以外的其他示踪剂、模型和分析方法将提供更多关于气溶胶来源的信息,并减小来源贡献率估算的不确定性.%The observation and source apportionment of carbonaceous aerosols is one of the focus of studies in the current scientific community. Radioactive (14C) and stable (13C) carbon isotopes have become useful tools in the source apportionment studies for carbonaceous aerosols. In this paper, we review the recent development of carbon isotope techniques, and explore its potential to be used for source apportionment for carbonaceous aerosols. It was pointed out that 14C has unique advantages in the quantitative distinguishment between fossil fuel and contemporary biomass combustion sources of atmospheric Organic Carbon (0C) and Black Carbon ( BC) , and that the combined C- C analysis can better constrain the sources of carbonaceous aerosols. Recent progress towards isolating OC and BC from other components of the particles has made it appicable to perform C measurements for OC and BC seperately. As for 13C, it was proposed that while it is very important to investigate the isotopic fraetionation mechanism of δ13C values of the carbonaceous aerosols, a regional δ13C signature map for the carbonacoues aerosols should be biult up aiming to facilitate explaining the δ13C variations and hence constraining the emisson sources. Future research that uses these carbon isotope techniques, in conjunction with other means such as

  14. Distribution and source apportionment of polycyclic aromatic hydrocarbons in surface soils in Shanghai%上海市表层土壤中多环芳烃的分布特征与源解析

    Institute of Scientific and Technical Information of China (English)

    杜芳芳; 杨毅; 刘敏; 陆敏; 于英鹏; 郑鑫; 刘营

    2014-01-01

    应用气相色谱-质谱联用仪(GC-MS)对上海市80个表层土壤样品中16种优控多环芳烃的浓度进行了测定,分析了上海市土壤中PAHs的含量分布特征,并利用同分异构体比值、主成分分析方法对表层土壤中的PAHs进行了源解析.结果表明,80个样点PAHs的含量在0.12~24.5μg/g之间,呈现出郊区>市区>农村的梯度变化,市区内不同功能区采样点呈现出交通区>文教区>公园绿地>商业区>住宅区的梯度变化. PAHs组成以4环和5环为主,平均含量分别占∑PAHs的49.2%和27.0%,其次为3环和6环,分别占∑PAHs的14.8%和6.6%,最低为2环PAHs,仅占2.4%,单体PAHs化合物以荧蒽、芘、苯并芘为主.源解析表明,表层土壤中PAHs的主要来源是燃烧源,主要是石油燃烧.%The concentrations of sixteen priority polycyclic aromatic hydrocarbons in 80 topsoil samples in Shanghai were determined by GC-MS. The distribution pattern was discussed, and source apportionment of PAHs in surface soil was conducted by the isomer ratio and principal component analysis. Results showed that the concentrations of PAHs ranged between 0.12μg/gand 24.5μg/g, presenting gradient changes of suburb>urban> rural and traffic area>cultural and educational area>park greenbelt>business district>residential in different functional areas in the city. Dominant compounds were 4rings and 5rings PAHs, which accounted for 49.2% and 27.0%, followed by 3and 6rings, which accounted for 14.8% and 6.6% of the total PAH concentrations, respectively. The lowest was the 2rings PAHs, which only accounted for 2.4% of the total PAH concentrations. In addition, fluoranthene, pyrene and benzopyrene were dominant PAH compounds. Source apportionment indicated that the PAHs originated mainly from burning, mainly oil burning.

  15. Levels and source apportionment of children's lead exposure: Could urinary lead be used to identify the levels and sources of children's lead pollution?

    International Nuclear Information System (INIS)

    As a highly toxic heavy metal, the pollution and exposure risks of lead are of widespread concern for human health. However, the collection of blood samples for use as an indicator of lead pollution is not always feasible in most cohort or longitudinal studies, especially those involving children health. To evaluate the potential use of urinary lead as an indicator of exposure levels and source apportionment, accompanying with environmental media samples, lead concentrations and isotopic measurements (expressed as 207Pb/206Pb, 208Pb/206Pb and 204Pb/206Pb) were investigated and compared between blood and urine from children living in the vicinities of a typical coking plant and lead-acid battery factory. The results showed urinary lead might not be a preferable proxy for estimating blood lead levels. Fortunately, urinary lead isotopic measurements could be used as an alternative for identifying the sources of children's lead exposure, which coincided well with the blood lead isotope ratio analysis. - Highlights: • Pb isotopes of environmental media and children's blood and urine were analyzed. • Pb exposure and pollution source were studied in lead-acid battery and coking areas. • Pb isotope ratios in blood and urine were similar to those of food, water and PM. • Urine Pb level may not be used as a proxy for indicating the lead levels in blood. • Urine Pb isotope ratios is an alternative to identify source and exposure pathways. - Urinary lead is not a preferable proxy to estimate blood lead level, but urinary lead isotope ratios could be an alternative for identifying the sources of lead exposure in children

  16. Source identification and apportionment of PM2.5 and PM2.5-10 in iron and steel scrap smelting factory environment using PMF, PCFA and UNMIX receptor models.

    Science.gov (United States)

    Ogundele, Lasun T; Owoade, Oyediran K; Olise, Felix S; Hopke, Philip K

    2016-10-01

    To identify the potential sources responsible for the particulate matter emission from secondary iron and steel smelting factory environment, PM2.5 and PM2.5-10 particles were collected using the low-volume air samplers twice a week for a year. The samples were analyzed for the elemental and black carbon content using x-ray fluorescence spectrometer and optical transmissometer, respectively. The average mass concentrations were 216.26, 151.68, and 138. 62 μg/m(3) for PM2.5 and 331.36, 190.01, and 184.60 μg/m(3) for PM2.5-10 for the production, outside M1 and outside M2 sites, respectively. The same size resolved data set were used as input for the positive matrix factorization (PMF), principal component factor analysis (PCFA), and Unmix (UNMIX) receptor modeling in order to identify the possible sources of particulate matter and their contribution. The PMF resolved four sources with their respective contributions were metal processing (33 %), e-waste (33 %), diesel emission (22 %) and soil (12 %) for PM2.5, and coking (50 %), soil (29 %), metal processing (16 %) and diesel combustion (5 %) for PM2.5-10. PCFA identified soil, metal processing, Pb source, and diesel combustion contributing 45, 41, 9, and 5 %, respectively to PM2.5 while metal processing, soil, coal combustion and open burning contributed 43, 38, 12, and 7 %, respectively to the PM2.5-10. Also, UNMIX identified metal processing, soil, and diesel emission with 43, 42 and 15 % contributions, respectively for the fine fraction, and metal processing (71 %), soil (21 %) and unidentified source (1 %) for the coarse fraction. The study concluded that metal processing and e-waste are the major sources contributing to the fine fraction while coking and soil contributed to the coarse fraction within the factory environment. The application of PMF, PCFA and UNMIX receptor models improved the source identification and apportionment of particulate matter drive in the study area.

  17. Source identification and apportionment of PM2.5 and PM2.5-10 in iron and steel scrap smelting factory environment using PMF, PCFA and UNMIX receptor models.

    Science.gov (United States)

    Ogundele, Lasun T; Owoade, Oyediran K; Olise, Felix S; Hopke, Philip K

    2016-10-01

    To identify the potential sources responsible for the particulate matter emission from secondary iron and steel smelting factory environment, PM2.5 and PM2.5-10 particles were collected using the low-volume air samplers twice a week for a year. The samples were analyzed for the elemental and black carbon content using x-ray fluorescence spectrometer and optical transmissometer, respectively. The average mass concentrations were 216.26, 151.68, and 138. 62 μg/m(3) for PM2.5 and 331.36, 190.01, and 184.60 μg/m(3) for PM2.5-10 for the production, outside M1 and outside M2 sites, respectively. The same size resolved data set were used as input for the positive matrix factorization (PMF), principal component factor analysis (PCFA), and Unmix (UNMIX) receptor modeling in order to identify the possible sources of particulate matter and their contribution. The PMF resolved four sources with their respective contributions were metal processing (33 %), e-waste (33 %), diesel emission (22 %) and soil (12 %) for PM2.5, and coking (50 %), soil (29 %), metal processing (16 %) and diesel combustion (5 %) for PM2.5-10. PCFA identified soil, metal processing, Pb source, and diesel combustion contributing 45, 41, 9, and 5 %, respectively to PM2.5 while metal processing, soil, coal combustion and open burning contributed 43, 38, 12, and 7 %, respectively to the PM2.5-10. Also, UNMIX identified metal processing, soil, and diesel emission with 43, 42 and 15 % contributions, respectively for the fine fraction, and metal processing (71 %), soil (21 %) and unidentified source (1 %) for the coarse fraction. The study concluded that metal processing and e-waste are the major sources contributing to the fine fraction while coking and soil contributed to the coarse fraction within the factory environment. The application of PMF, PCFA and UNMIX receptor models improved the source identification and apportionment of particulate matter drive in the study area. PMID:27645143

  18. Revenue management in order-driven production systems:Modifications of dynamic capacity apportionment procedure%订单驱动生产系统中的收益管理——对动态产能分配机制的改进

    Institute of Scientific and Technical Information of China (English)

    陶星; 丁邡; 蓝颖杰; 王其文

    2013-01-01

    The dynamic capacity apportionment procedure (DCAP) is a heuristic revenue management method applicable in an order-driven production system. This article improves upon the DCAP in two important aspects: 1) Through further refining one of DCAP's scenarios, it gave the approximate revenue function based on the apportionment ratio of the remaining unreserved capacity. 2) It proposed a new approach to calculating the apportionment ratio, which effectively improves all the estimated revenue functions that involve such a ratio, and promotes the overall accuracy of DCAP and the decisions that follow. A simulation experiment showed improved DCAP (IDCAP) indeed performs better for various simulation settings, using exactly the same scheduling algorithm. This work enriches the theory of DCAP and potentially improve productivity.%动态产能分配机制(DCAP)是一种应用于订单驱动生产系统的启发式收益管理方法.通过更精细地分析,对DCAP在如下两方面进行了重要改进:1)细分了DCAP四个场景的一个,并给出了基于剩余未保护产能分配比例估算收益函数的方法;2)提出了一种新的近似计算分配比例的方法,改进了所有涉及分配比例的收益函数,从而提高了DCAP的精确度和相应决策的正确性,计算模拟验证了,在运用相同排程方法的前提下,改进后的方法(IDCAP)在众多模拟情景中优于原有的DCAP.这些工作改善了DCAP的理论分析,并对生产实践有较好的指导意义.

  19. 基于UNMIX模型的夹皮沟金矿区土壤重金属源解析%Source Apportionment of Soil Heavy Metals in Jiapigou Goldmine Based on the UNMIX Model

    Institute of Scientific and Technical Information of China (English)

    艾建超; 王宁; 杨净

    2014-01-01

    采集松花江上游夹皮沟地区的土壤样品,测定了16种金属元素的含量,应用美国环境保护署推荐的UNMIX模型进行了土壤重金属的源解析研究,并结合克里格插值法提取的Hg、Pb和Cd浓度等值线图与实际的调查,佐证源解析的结果.研究表明:①土壤样品中Cd、Hg、 Pb、 Ag浓度较高,超过吉林省土壤背景值,富集程度明显;②UNMIX方法解析出4个土壤重金属污染来源:源1代表选矿、公路交通及垃圾排放等人类活动的污染,源贡献率为39.31℅;源2代表岩石风化和生物作用,贡献率为13.87℅;源3为土壤母质和施用化肥、居民燃煤导致的综合污染源,贡献率23.93℅;源4代表铁矿开采及运输,贡献率为22.89℅.③研究区土地利用类型、人类活动调查、Hg、Pb、Cd含量分布特征与UNMIX模型解析的结果是基本吻合的.%The paper determines 16 kinds of metal elements' concentration in soil samples which collected in Jipigou goldmine upper the Songhua River. The UNMIX Model which was recommended by US EPA to get the source apportionment results was applied in this study, Cd, Hg, Pb and Ag concentration contour maps were generated by using Kriging interpolation method to verify the results. The main conclusions of this study are:①the concentrations of Cd, Hg, Pb and Ag exceeded Jilin Province soil background values and enriched obviously in soil samples;②using the UNMIX Model resolved four pollution sources:source 1 represents human activities of transportation, ore mining and garbage, and the source 1‘s contribution is 39. 1℅; Source 2 represents the contribution of the weathering of rocks and biological effects, and the source 2‘s contribution is 13. 87℅;Source 3 is a comprehensive source of soil parent material and chemical fertilizer, and the source 3‘s contribution is 23. 93℅; Source 4 represents iron ore mining and transportation sources, and the source 4

  20. Iodine source apportionment in the Malawian diet

    Science.gov (United States)

    Watts, M. J.; Joy, E. J. M.; Young, S. D.; Broadley, M. R.; Chilimba, A. D. C.; Gibson, R. S.; Siyame, E. W. P.; Kalimbira, A. A.; Chilima, B.; Ander, E. L.

    2015-10-01

    The aim of this study was to characterise nutritional-I status in Malawi. Dietary-I intakes were assessed using new datasets of crop, fish, salt and water-I concentrations, while I status was assessed for 60 women living on each of calcareous and non-calcareous soils as defined by urinary iodine concentration (UIC). Iodine concentration in staple foods was low, with median concentrations of 0.01 mg kg-1 in maize grain, 0.008 mg kg-1 in roots and tubers, but 0.155 mg kg-1 in leafy vegetables. Freshwater fish is a good source of dietary-I with a median concentration of 0.51 mg kg-1. Mean Malawian dietary-Iodine intake from food, excluding salt, was just 7.8 μg d-1 compared to an adult requirement of 150 μg d-1. Despite low dietary-I intake from food, median UICs were 203 μg L-1 with only 12% defined as I deficient whilst 21% exhibited excessive I intake. Iodised salt is likely to be the main source of dietary I intake in Malawi; thus, I nutrition mainly depends on the usage and concentration of I in iodised salt. Drinking water could be a significant source of I in some areas, providing up to 108 μg d-1 based on consumption of 2 L d-1.

  1. Arm's Length Principle vs. Formulary Apportionment Method: A Discussion at Length Caused by the Award to the Case%转移定价问题的公平交易法与全球公式法之争——美国法院一个新近判决引起的轩然大波

    Institute of Scientific and Technical Information of China (English)

    那力

    2011-01-01

    With the background of economic globalization and knowledge economy, multination- al corporations' business are getting more and more transnational, and the battle of arm's length principle vs. global formulary apportionment has been surging on. The recen%在经济全球化和知识经济的背景下,跨国企业经营的全球化趋势愈发加强,公平交易法与全球公式法之争愈发激烈。最近,美国法院的一起判决,在世界范围内,特别是在北美与欧洲,引起了轩然大波,通过此案和对此案的热烈讨论及激烈争辩,我们又一次感到了全球公式法对国际税法冲击是必然的、实质性的,颠覆性的改变是可能发生的。这个问题对有大量资本引进来、走出去的我国来说非常重要。我们必须跟踪这个问题的发展,及早做好准备。

  2. Organizações indígenas e distritalização sanitária: os riscos de "fazer ver" e "fazer crer" nas políticas de saúde Indigenous organizations and health district apportionment: the gap between seeing and believing in health policies

    Directory of Open Access Journals (Sweden)

    Luiza Garnelo

    2005-08-01

    Full Text Available O trabalho se propõe a analisar repercussões etnopolíticas, éticas e sanitárias nas práticas das organizações indígenas, conveniadas com o Ministério da Saúde, ligadas ao processo de implantação dos Distritos Sanitários Especiais Indígenas (DSEI no Estado do Amazonas, Brasil. Os DSEI escolhidos para análise foram o de Manaus e do Rio Negro. As informações trabalhadas são retiradas de relatórios de encontros, reuniões de planejamento e de gestão das convenentes indígenas, da observação participante em eventos de avaliação do processo de distritalização e entrevistas com gerentes indígenas e não indígenas dos DSEI. É discutida a ambigüidade das organizações indígenas de ter que exercer o seu papel político e ao mesmo tempo de executoras de uma política do Estado, assumindo como uma forma de superação do estigma de incapacidade de estar à frente do processo de implantação dos DSEI.This study aims to analyze the ethno-political, ethical, and health repercussions, for indigenous peoples' organizations involved in agreements with the Ministry of Health, resulting from the implementation of Special Indigenous Health Districts (DSEI in the State of Amazonas, Brazil. The DSEIs chosen for analysis were those of Manaus and Rio Negro. Data were collected from reports drafted during and after planning and other meetings of the respective indigenous peoples' organizations, participatory observation in events organized to evaluate the health district apportionment process, and interviews with indigenous and non-indigenous managers of DSEIs. The article discusses the ambiguity of indigenous peoples' organizations in having to exercise their own political role while implementing a state policy, assumed as a way to overcome the stigma of their presumed inability to head the process of implementing a DSEI.

  3. Source apportionment of PM2.5 in Seoul, Korea

    Directory of Open Access Journals (Sweden)

    S.-M. Yi

    2008-12-01

    Full Text Available PM2.5 samples were collected at a centrally located urban monitoring site in Seoul, Korea, every third day from March 2003 to December 2006 and analyzed for their chemical constituents. Sources were identified using Positive Matrix Factorization (PMF. A total of 393 samples were obtained during the sampling period, and 20 chemical species were measured. Nine PM2.5 sources were identified providing physically realistic profiles and interesting insights into the source contributions to the ambient mass concentrations. The major sources of PM2.5 were secondary nitrate (20%, secondary sulfate (20%, gasoline-fueled vehicles (17%, and biomass burning (12%, with lesser contributions from diesel emissions (8%, soil (7%, industry (6%, road salt and two-stroke engine (5%, and aged sea salt (2%. PM2.5 levels in Seoul were influenced by both local urban activities and regional-scale transport. Conditional Probability Function (CPF results identified possible source directions of local sources such as motor vehicles (gasoline and diesel, industry, and road salt. Potential Source Contribution Function (PSCF results showed that possible source areas contributing to the elevated secondary particle concentrations (sulfate and nitrate in Seoul to be the major industrial areas in China.

  4. Source apportionment of PM2.5 in Seoul, Korea

    Science.gov (United States)

    Heo, J.-B.; Hopke, P. K.; Yi, S.-M.

    2008-12-01

    PM2.5 samples were collected at a centrally located urban monitoring site in Seoul, Korea, every third day from March 2003 to December 2006 and analyzed for their chemical constituents. Sources were identified using Positive Matrix Factorization (PMF). A total of 393 samples were obtained during the sampling period, and 20 chemical species were measured. Nine PM2.5 sources were identified providing physically realistic profiles and interesting insights into the source contributions to the ambient mass concentrations. The major sources of PM2.5 were secondary nitrate (20%), secondary sulfate (20%), gasoline-fueled vehicles (17%), and biomass burning (12%), with lesser contributions from diesel emissions (8%), soil (7%), industry (6%), road salt and two-stroke engine (5%), and aged sea salt (2%). PM2.5 levels in Seoul were influenced by both local urban activities and regional-scale transport. Conditional Probability Function (CPF) results identified possible source directions of local sources such as motor vehicles (gasoline and diesel), industry, and road salt. Potential Source Contribution Function (PSCF) results showed that possible source areas contributing to the elevated secondary particle concentrations (sulfate and nitrate) in Seoul to be the major industrial areas in China.

  5. Source apportionment of fine particles in Kuwait City.

    Science.gov (United States)

    Alolayan, Mohammad A; Brown, Kathleen W; Evans, John S; Bouhamra, Walid S; Koutrakis, Petros

    2013-03-15

    This study investigated major sources of PM2.5 in the atmosphere of Kuwait based on a sampling program conducted between February 2004 and October 2005. Three source identification techniques were used in this study: (1) a positive matrix factorization model; (2) backward trajectory profiles; and (3) concentration rose plots. Five major sources of PM2.5 were estimated. These were sand dust (sand storms), oil combustion (power plants), petrochemical industry (fertilizer, nylon or catalyst regeneration facilities), traffic (vehicle emissions and road dust) and transported emissions (emissions from outside Kuwait, such as those from automobiles, road dust or smelters). The estimated contributions to PM2.5 of these sources were: 54% from sand dust, 18% from oil combustion, 12% from petrochemical industry, 11% from traffic and 5% from anthropogenic sources transported from outside the country. Oil combustion, petrochemical industry and traffic were found to emanate from local sources, whereas sand dust and some emissions from traffic, and possibly smelters, appeared to originate from sources outside of Kuwait (transported). The PM2.5 levels in Kuwait during our previous sampling study averaged 53μg/m(3). More than half of the measured PM2.5 appears to have been due to crustal material, much originating outside of the country. However, the relatively high levels of PM2.5 contributed by anthropogenic local sources, such as oil combustion, petrochemical industry emissions, and traffic indicated that there may be great opportunities for Kuwait to improve public health. The application of cost-effective emission controls and development of forward looking environmental health policies have the potential to significantly reduce emissions, population exposures to PM2.5 and the burden of mortality and morbidity from air pollution.

  6. Suspended sediment apportionment in a South-Korean mountain catchment

    Science.gov (United States)

    Birkholz, Axel; Meusburger, Katrin; Park, Ji-Hyung; Alewell, Christine

    2016-04-01

    Due to the rapid agricultural expansion and intensification during the last decades in South-Korea, large areas of hill slope forests were transformed to paddies and vegetable fields. The intensive agriculture and the easily erodible soils in our catchment are a major reason for the increased erosion causing suspended sediments to infiltrate into the close drinking water reservoir. The drinking water reservoir Lake Soyang provides water supply for over ten million people in Seoul. Landscape managers need to know the exact origin of these sediments before they can create landscape amelioration schemes. We applied a compound-specific stable isotope (CSSI) approach (Alewell et al., 2015) to apportion the sources of the suspended sediments between forest and agricultural soil contribution to the suspended sediments in a different catchment and applied the same approach to identify and quantify the different sources of the suspended sediments in the river(s) contributing to Lake Soyang. We sampled eight soil sites within the catchment considering the different landuse types forest, rice paddies, maize and vegetables. Suspended sediments were sampled at three outlets of the different sub-catchments. Soils and suspended sediments are analysed for bulk carbon and nitrogen isotopes, compound-specific carbon isotopes of plant-wax derived long-chain fatty acids and long-chain n-alkanes. Fatty acid and alkane isotopes are then used in mixing calculations and the mixing model software IsoSource to find out the contribution of the different source soils to the suspended sediments. We present first data of the source soils and the suspended sediments. C. Alewell, A. Birkholz, K. Meusburger, Y. Schindler-Wildhaber, L. Mabit, 2015. Sediment source attribution from multiple land use systems with CSIA. Biogeosciences Discuss. 12: 14245-14269.

  7. Source apportionment using LOTOS-EUROS: module description and evaluation

    Science.gov (United States)

    Kranenburg, R.; Segers, A. J.; Hendriks, C.; Schaap, M.

    2013-06-01

    To design effective mitigation strategies, the origin of emissions which produce air pollutants needs to be known. Contributors to air pollutants can be emission sources, like road traffic or industry, but also be more specified to emission from one location or from a specified time. Chemistry transport models can be used to assess the origin of air pollution across a large domain. However, in traditional simulations the information on origin is lost and brute force scenario studies are performed to assess the origin. Alternatively, one can trace the origin of air pollutants throughout a simulation using a labeling approach. In this paper we document and demonstrate a newly developed labeling module for the chemistry transport model LOTOS-EUROS which tracks the source allocation for all particulate matter components and precursor gases. Dedicated simulations confirmed that the new module functions correctly. The new module provides more accurate information about the source contributions than using a brute force approach with scenario runs as the chemical regime remains unchanged. An important advantage of the new module is the reduction of computation costs and analysis work associated with the calculations. The new module was applied to assess the origin of particulate nitrate across the Netherlands. Averaged across the Dutch territory, the main contributions to nitrate are derived from road and non-road transport as well as power plants. Overall, only one-fifth of the concentration derived from sources located inside the country. The new technology enables new research directions as improved information on pollution origin is desired for policy support as well as scientific applications.

  8. Software for Apportionment of Asbestos-Related Mesotheliomas

    Science.gov (United States)

    Ross, Robert M.

    2016-01-01

    Patients with an asbestos-related mesothelioma may be legally entitled to financial compensation. In this context, a physician may be called upon to apportion the contribution of an asbestos containing product or facility where there was asbestos exposure in the development of that individual's mesothelioma. This task is mathematically not simple. It is a complex function of each and the entire individual's above-background asbestos exposures. Factors to be considered for each of these exposures are the amount of exposure to mesotheliogenic fibers, each of the asbestos containing products' potency to cause mesothelioma, and the time period when the exposures occurred relative to when the mesothelioma was diagnosed. In this paper, the known factors related to asbestos-related mesothelioma risk are briefly reviewed and the software that is downloadable and fully functional in a Windows® environment is also provided. This software allows for rapid assessment of relative contributions and deals with the somewhat tedious mathematical calculations. With this software and a reasonable occupational history, if it is decided that the mesothelioma was due to above-background asbestos exposure, the contribution of an asbestos containing product or a time period of asbestos exposure can be apportioned.

  9. Software for Apportionment of Asbestos-Related Mesotheliomas.

    Science.gov (United States)

    Ross, Robert M

    2016-01-01

    Patients with an asbestos-related mesothelioma may be legally entitled to financial compensation. In this context, a physician may be called upon to apportion the contribution of an asbestos containing product or facility where there was asbestos exposure in the development of that individual's mesothelioma. This task is mathematically not simple. It is a complex function of each and the entire individual's above-background asbestos exposures. Factors to be considered for each of these exposures are the amount of exposure to mesotheliogenic fibers, each of the asbestos containing products' potency to cause mesothelioma, and the time period when the exposures occurred relative to when the mesothelioma was diagnosed. In this paper, the known factors related to asbestos-related mesothelioma risk are briefly reviewed and the software that is downloadable and fully functional in a Windows® environment is also provided. This software allows for rapid assessment of relative contributions and deals with the somewhat tedious mathematical calculations. With this software and a reasonable occupational history, if it is decided that the mesothelioma was due to above-background asbestos exposure, the contribution of an asbestos containing product or a time period of asbestos exposure can be apportioned. PMID:27445546

  10. Receptor modeling application framework for particle source apportionment.

    Science.gov (United States)

    Watson, John G; Zhu, Tan; Chow, Judith C; Engelbrecht, Johann; Fujita, Eric M; Wilson, William E

    2002-12-01

    Receptor models infer contributions from particulate matter (PM) source types using multivariate measurements of particle chemical and physical properties. Receptor models complement source models that estimate concentrations from emissions inventories and transport meteorology. Enrichment factor, chemical mass balance, multiple linear regression, eigenvector. edge detection, neural network, aerosol evolution, and aerosol equilibrium models have all been used to solve particulate air quality problems, and more than 500 citations of their theory and application document these uses. While elements, ions, and carbons were often used to apportion TSP, PM10, and PM2.5 among many source types, many of these components have been reduced in source emissions such that more complex measurements of carbon fractions, specific organic compounds, single particle characteristics, and isotopic abundances now need to be measured in source and receptor samples. Compliance monitoring networks are not usually designed to obtain data for the observables, locations, and time periods that allow receptor models to be applied. Measurements from existing networks can be used to form conceptual models that allow the needed monitoring network to be optimized. The framework for using receptor models to solve air quality problems consists of: (1) formulating a conceptual model; (2) identifying potential sources; (3) characterizing source emissions; (4) obtaining and analyzing ambient PM samples for major components and source markers; (5) confirming source types with multivariate receptor models; (6) quantifying source contributions with the chemical mass balance; (7) estimating profile changes and the limiting precursor gases for secondary aerosols; and (8) reconciling receptor modeling results with source models, emissions inventories, and receptor data analyses.

  11. Source apportionment using LOTOS-EUROS: module description and evaluation

    OpenAIRE

    Kranenburg, R. van; A. J. Segers; Hendriks, C.; Schaap, M.

    2013-01-01

    To design effective mitigation strategies, the origin of emissions which produce air pollutants needs to be known. Contributors to air pollutants can be emission sources, like road traffic or industry, but also be more specified to emission from one location or from a specified time. Chemistry transport models can be used to assess the origin of air pollution across a large domain. However, in traditional simulations the information on origin is lost and brute force scenario...

  12. Source apportionment using LOTOS-EUROS: module description and evaluation

    Directory of Open Access Journals (Sweden)

    R. Kranenburg

    2013-06-01

    Full Text Available To design effective mitigation strategies, the origin of emissions which produce air pollutants needs to be known. Contributors to air pollutants can be emission sources, like road traffic or industry, but also be more specified to emission from one location or from a specified time. Chemistry transport models can be used to assess the origin of air pollution across a large domain. However, in traditional simulations the information on origin is lost and brute force scenario studies are performed to assess the origin. Alternatively, one can trace the origin of air pollutants throughout a simulation using a labeling approach. In this paper we document and demonstrate a newly developed labeling module for the chemistry transport model LOTOS-EUROS which tracks the source allocation for all particulate matter components and precursor gases. Dedicated simulations confirmed that the new module functions correctly. The new module provides more accurate information about the source contributions than using a brute force approach with scenario runs as the chemical regime remains unchanged. An important advantage of the new module is the reduction of computation costs and analysis work associated with the calculations. The new module was applied to assess the origin of particulate nitrate across the Netherlands. Averaged across the Dutch territory, the main contributions to nitrate are derived from road and non-road transport as well as power plants. Overall, only one-fifth of the concentration derived from sources located inside the country. The new technology enables new research directions as improved information on pollution origin is desired for policy support as well as scientific applications.

  13. Source apportionment using LOTOS-EUROS: module description and evaluation

    Directory of Open Access Journals (Sweden)

    R. Kranenburg

    2012-11-01

    Full Text Available To design effective mitigation strategies the origin of air pollutants needs to be known. Chemistry transport models can be used to assess the origin of air pollution across a large domain. However, in traditional simulations the information on origin is lost and brute force scenario studies are performed to assess the origin. Alternatively, one can trace the origin of air pollutants throughout a simulation using a labeling approach. In this paper we document and demonstrate a newly developed labeling module for the chemistry transport model LOTOS-EUROS which tracks the source allocation for all particulate matter components and precursor gases. Dedicated simulations confirmed that the new module functions correctly. The new module provides more accurate information about the source contributions than using a brute force approach with scenario runs as the chemical regime remains unchanged. An important advantage of the new module is the reduction of computation costs and analysis work associated with the calculations. The new module was applied to assess the origin of particulate nitrate across the Netherlands. Averaged across the Dutch territory the main contributions to nitrate derive from road and non-road transport as well as power plants. Overall, only one-fifth of the concentration derived from sources located inside the country. The new technology enables new research directions as improved information on pollution origin is desired for policy support as well as scientific applications.

  14. Atmospheric Source Apportionment of PCBs Using Chiral Signatures

    Directory of Open Access Journals (Sweden)

    A Jamshidi

    2005-10-01

    Full Text Available Polychlorinated biphenyls (PCBs are organochlorine chemicals that found widespread use in a diverse range of applications, with around 1.2 million tones produced worldwide. Although, the production of PCBs was banned in western nations in order to health concerns in the late 1970s, concentrations in the environment remain elevated, particularly in urban areas. There are two principal sources for atmospheric PCBs; primary source (ventilation of indoor air contaminated via leakage from old electrical equipment, building materials and secondary source (volatilisation from soil contaminated as a result of past releases. Recent literature suggests that while PCB volatilisation from soil is likely to constitute a significant source of atmospheric PCB, new sources (primary such as the ventilation of contaminated indoor air may constitute the most important contributions in urban areas. Aim: to evaluate the relative significance of primary and secondary sources of PCBs to the atmosphere at a number of locations in the West Midlands. Chiral analysis was employed to monitor enantiomeric fractions of selected chiral PCBs in topsoil and outdoor air over a one-year period. Overall 220 air and soil samples were collected from 10 different sites. Sampling locations were located on a southwest (upwind to northeast (downwind transect at intervals of between 3 and 15 km across the conurbation. In this way, a mix of rural, suburban, and urban sampling locations was studied. Samples were extracted, purified, and subjected to chiral GC/MS as previously described. Result: EFs in air for PCBs 136 and 149 are essentially racemic (EF= 0.5± 0.005 at all locations, while the EFs for PCB 95 in air are less obviously racemic, but display appreciable divergence from the EFs found in the corresponding soil samples. Volatilisation from soil appears to make a minimal contribution to atmospheric PCB concentrations at these locations. EFs of PCBs 95 and 136 are essentially racemic in all samples taken at the most urban location, which we tentatively hypothesised, was due to impaired microbial activity. The racemic EFs at Centenary Square may also reflect the fact that at this highly urbanised location, the supply of atmospheric PCB inputs (for which EFs are essentially racemic may exceed the rate at which enantioselective degradation occurs. Further tentative support for this inverse relationship between degree of urbanisation and extent of enantioselective degradation comes from the fact that the greatest enantioselective degradation is observed at the most rural locations. An ANOVA test of chiral signatures in soil samples at each location in this study reveals no statistically significant seasonal or temporal (month - to - month difference in edaphic chiral signatures. Furthermore, there are congener-specific variations in the extent of enantioselective degradation, with PCB 95 being degraded more than PCB 136 and 149. The direction of this enantioselective degradation is also broadly in line with our previous findings, although there appears to be less enantioselective degradation of 136 than previously observed. These results have potentially important implications for public health and environmental protection, as they imply that destruction of PCB stocks remaining in use in indoor environments are likely to result in a significant reduction in atmospheric concentrations. As the atmosphere is the principal point of entry of PCBs into the food chain, and is also the principal vector via which PCBs are transported from their – largely urban - source regions, such action is likely to reduce human exposure and limit the future spread of these compounds.

  15. Source apportionment studies on particulate matter in Beijing/China

    Science.gov (United States)

    Suppan, P.; Shen, R.; Shao, L.; Schrader, S.; Schäfer, K.; Norra, S.; Vogel, B.; Cen, K.; Wang, Y.

    2013-05-01

    More than 15 million people in the greater area of Beijing are still suffering from severe air pollution levels caused by sources within the city itself but also from external impacts like severe dust storms and long range advection from the southern and central part of China. Within this context particulate matter (PM) is the major air pollutant in the greater area of Beijing (Garland et al., 2009). PM did not serve only as lead substance for air quality levels and therefore for adverse health impact effects but also for a strong influence on the climate system by changing e.g. the radiative balance. Investigations on emission reductions during the Olympic Summer Games in 2008 have caused a strong reduction on coarser particles (PM10) but not on smaller particles (PM2.5). In order to discriminate the composition of the particulate matter levels, the different behavior of coarser and smaller particles investigations on source attribution, particle characteristics and external impacts on the PM levels of the city of Beijing by measurements and modeling are performed: a) Examples of long term measurements of PM2.5 filter sampling in 2010/2011 with the objectives of detailed chemical (source attribution, carbon fraction, organic speciation and inorganic composition) and isotopic analyses as well as toxicological assessment in cooperation with several institutions (Karlsruhe Institute of Technology (IfGG/IMG), Helmholtz Zentrum München (HMGU), University Rostock (UR), Chinese University of Mining and Technology Beijing, CUMTB) will be discussed. b) The impact of dust storm events on the overall pollution level of particulate matter in the greater area of Beijing is being assessed by the online coupled comprehensive model system COSMO-ART. First results of the dust storm modeling in northern China (2011, April 30th) demonstrates very well the general behavior of the meteorological parameters temperature and humidity as well as a good agreement between modeled and measured dust storm concentration variability at Beijing in the course of time. The results show the importance of intertwine investigations of measurements and modeling, the analysis of local air pollution levels as well as the impact and analysis of advective processes in the greater region of Beijing. Comprehensive investigations on particulate matter are a prerequisite for the knowledge of the source strengths and source attribution to the overall air pollution level. Only this knowledge can help to formulate and to introduce specific reduction measures to reduce coarser as well as finer particulates.

  16. Source apportionment of ambient VOCS in Mumbai city

    Science.gov (United States)

    Srivastava, Anjali

    Air pollution kills almost half a million Asians every year. Most of this pollution is emitted from buses, trucks, motorcycles and other forms of transport. As Asia's cities continue to expand, the rising number of vehicles has resulted in even greater pollution. Amongst the measures available to control, vehicular emission was engine modification, catalytic converters and fuel modifications. Some of these have led to emissions of some hazardous air pollutants (HAP) like volatile organic compounds (VOCs). VOC emission is an area needing attention in air quality management. This paper discusses a study on VOC concentration at major sources like traffic junction, residential area, commercial areas, industrial areas and petrol pumps in Mumbai city. CMB8 Model has been used to apportion VOCs in Mumbai city. It was observed that evaporative emissions dominate in Mumbai. In order to control VOCs in air the management strategy should thus focus on cost effective vapor recovery systems at refueling stations and in vehicles. Effective inspection and maintenance programme can reduce evaporative and exhaust VOC emissions. Modifying certain fuel parameters, like reducing benzene content in petrol will as well reduce VOC content in air. The benzene content in petrol was 3% in the year 2001 in Mumbai. Adulteration also results in high levels of VOCs in air.

  17. Source apportionment of PM2.5 in Incheon, Korea

    Science.gov (United States)

    Choi, J.; Ban, S.; Lee, C.; Yi, S.; Zoh, K.

    2011-12-01

    PM2.5 samples were collected at a centrally located urban monitoring site in Incheon, Korea, every third day from Jun 2009 to may 2010 and analyzed their chemical species. In this study, we investigated the source of PM2.5 using Positive Matrix Factorization(PMF), the source area from Potential Source Contribution Function (PSCF) and Conditional Probability Function(CPF), and characterized source variation among episode, non-episode, yellow sand events. Incheon, study site, is located at the mid-western tip of the Korean Peninsula with a population of 2.6 million people and area of 1029.4 km2, respectively. As a transportation hub, the city also holds the importance of meteological/geological aspect affecting the air quality of capital region, in that is prevailing westerlies zone and a air passageway from China to Japan passing through seoul, korea. In the study, the Four channel based on Annular Denuder System(ADS) were used for sample collection(URG co, USA). The filter samples were analyzed with respect to species type such as ion group, metal, and OC/EC compound using ion chromatography, ICP/MS, and NIOSH TOT method, respectively. The PM2.5 concentration was 43ug/m3 that is almost three times higher than the US NAAQS annual PM2.5 standard of 15ug/m3. Nine PM2.5 sources were resolved from PMF analysis that provided reasonable source profiles and interesting insights into the source contributions to the ambient mass concentrations. The major sources of PM2.5 were secondary nitrate(26.4%), secondary sulfate(17.3%), gasoline(16.4%), and residual oil combustion(13.5%), with lesser contributions from biomass burning (7.5%), road dust(6.9%), soil (5.5%), coal fire powerplant (4.0%), and free sea salt(2.4%). CPF results identified possible local source directions such as motor vehicles, free sea salt. PSCF results indicated that likely pollution areas increased secondary particle concentrations(sulfate and nitrate) in Incheon to be the major industrial areas in China. Finally, smog event are characterized by their high concentrations of free sea salt, gasoline, secondary nitrate, secondary sulfate source. On the other hand, yellow event are characterized by their high concentrations of soil source.Percnetage factor contribution of PM2.5 mass concentration at Incheon

  18. Mercury isotopes of atmospheric particle bound mercury for source apportionment study in urban Kolkata, India

    Directory of Open Access Journals (Sweden)

    Reshmi Das

    2016-04-01

    Full Text Available Abstract The particle bound mercury (PBM in urban-industrial areas is mainly of anthropogenic origin, and is derived from two principal sources: Hg bound to particulate matter directly emitted by industries and power generation plants, and adsorption of gaseous elemental mercury (GEM and gaseous oxidized mercury (GOM on air particulates from gas or aqueous phases. Here, we measured the Hg isotope composition of PBM in PM10 samples collected from three locations, a traffic junction, a waste incineration site and an industrial site in Kolkata, the largest metropolis in Eastern India. Sampling was carried out in winter and monsoon seasons between 2013–2015. The objective was to understand whether the isotope composition of the PBM represents source composition. The PBM collected from the waste burning site showed little mass independent fractionation (MIF (Δ199Hg = +0.12 to -0.11‰, similar to the signature in liquid Hg and Hg ores around the world with no seasonal variations. Samples from the industrial site showed mostly negative MDF and MIF (δ202Hg = -1.34 to -3.48 ‰ and Δ199Hg = +0.01 to -0.31‰. The MDF is consistent with PBM generated by coal combustion however, the MIF is 0.15‰ more negative compared to the Hg isotope ratios in Indian coals. The traffic junction PBM is probably not produced in situ, but has travelled some distances from nearby industrial sources. The longer residence time of this PBM in the atmosphere has resulted in-aerosol aqueous photoreduction. Thus, the MIF displays a larger range (Δ199Hg = +0.33 to -0.30‰ compared to the signature from the other sites and with more positive values in the humid monsoon season. Different Hg isotopic signature of PBM in the three different sampling locations within the same city indicates that both source and post emission atmospheric transformations play important roles in determining isotopic signature of PBM.

  19. Large chemical characterisation of PM10 emitted from graphite material production: Application in source apportionment.

    Science.gov (United States)

    Golly, B; Brulfert, G; Berlioux, G; Jaffrezo, J-L; Besombes, J-L

    2015-12-15

    This work focuses on emissions from industrial sources that are still poorly understood in Europe, especially the "carbon industry". The study is based on two intensive sampling campaigns performed in a graphite material production plant for 2weeks in July 2013 and November 2013 in alpine valleys. The chemical characterization of PM10 was conducted at three sampling sites (outdoor and indoor sites) located inside one industrial area, which is considered as the highest emissions source of polycyclic aromatic hydrocarbons (PAHs) in the Arve valley. The identification of specific tracers among metals and trace elements is commonly used to characterize industrial emissions. In our study, original enrichment factors relative to the "rural exposed background" have been calculated, and the metallic fraction was not affected by this industrial source. In contrast, the organic fraction of PM10 has a number of features, providing a complete organic source profile and referred to as the "carbon industry". In particular, polycyclic aromatic sulfur heterocycles (PASH) have been largely detected from fugitive emissions with rather large concentrations. The average concentrations of benzo(b)naphtho(2,1-d)thiophene (BNT(2,1)) reached 2.35-6.56ng·m(-3) and 60.5-376ng·m(-3) for outdoor and indoor sites, respectively. The use of this reference profile in the chemical mass balance model (CMB) applied to samples collected in two sites near industrial areas shows that this source had an average contribution of 6% of the organic matter (OM) mass during the sampling period during the winter of 2013.

  20. Chemical characterization of atmospheric particles and source apportionment in the vicinity of a steelmaking industry

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, S.M., E-mail: smarta@ctn.ist.utl.pt [Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10, 139.7 km, 2695-066 Bobadela LRS (Portugal); Lage, J. [Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10, 139.7 km, 2695-066 Bobadela LRS (Portugal); Fernández, B. [Global R& D, ArcelorMittal, Avilés (Spain); Garcia, S. [Instituto de Soldadura e Qualidade, Av. Prof. Dr. Cavaco Silva, 33, 2740-120 Porto Salvo (Portugal); Reis, M.A.; Chaves, P.C. [Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10, 139.7 km, 2695-066 Bobadela LRS (Portugal)

    2015-07-15

    The objective of this work was to provide a chemical characterization of atmospheric particles collected in the vicinity of a steelmaking industry and to identify the sources that affect PM{sub 10} levels. A total of 94 PM samples were collected in two sampling campaigns that occurred in February and June/July of 2011. PM{sub 2.5} and PM{sub 2.5–10} were analyzed for a total of 22 elements by Instrumental Neutron Activation Analysis and Particle Induced X-ray Emission. The concentrations of water soluble ions in PM{sub 10} were measured by Ion Chromatography and Indophenol-Blue Spectrophotometry. Positive Matrix Factorization receptor model was used to identify sources of particulate matter and to determine their mass contribution to PM{sub 10}. Seven main groups of sources were identified: marine aerosol identified by Na and Cl (22%), steelmaking and sinter plant represented by As, Cr, Cu, Fe, Ni, Mn, Pb, Sb and Zn (11%), sinter plant stack identified by NH{sub 4}{sup +}, K and Pb (12%), an unidentified Br source (1.8%), secondary aerosol from coke making and blast furnace (19%), fugitive emissions from the handling of raw material, sinter plant and vehicles dust resuspension identified by Al, Ca, La, Si, Ti and V (14%) and sinter plant and blast furnace associated essentially with Fe and Mn (21%). - Highlights: • Emissions from steelworks are very complex. • The larger steelworks contribution to PM{sub 10} was from blast furnace and sinter plant. • Sinter plant stack emissions contributed for 12% of the PM{sub 10} mass. • Secondary aerosol from coke making and blast furnace contributed for 19% of the PM{sub 10}. • Fugitive dust emissions highly contribute to PM{sub 10} mass.

  1. Characteristics and source apportionment of atmospheric aerosols at the summit of Mount Tai during summertime

    Directory of Open Access Journals (Sweden)

    H. Xu

    2009-07-01

    Full Text Available To investigate the long-range transport of air pollutants in North China, aerosol samples were collected at the summit of Mount Tai (Shandong province in June of 2006. Water-soluble ion and metal element concentrations were analyzed using ion chromatography (IC and inductively coupled plasma-mass spectrometry (ICP-MS, respectively. Results showed three different size distributions for the ions and metal elements characterized, including masses in: (i the accumulation mode, with a peak at 0.43 to 1.1 μm (SO42−, NH4+, K+, Pb, Zn, Ti; (ii the coarse particle mode, with a peak at 4.7 to 5.8 μm (Ca2+, Mg2+, Ca, Mg, Fe, Al, Ba, Mn; and (iii a bimodal distribution, with peaks at 0.43 to 0.65 μm and 4.7 to 5.8 μm (NO3, Na+, Cl, Na, Co, Ni, Mo, Cu. When SO42− was in high concentration, the mass median diameter was between 0.5 μm and 0.8 μm, belonging to the "drop mode". The concentrations of SO42−, NO3, NH4+, and K+ were quite variable. Interestingly, SO42−, NO3, and NH4+ reached their highest concentrations when the humid air mass was coming from the south. Furthermore, crustal element concentrations increased when the air mass came from the north and pollution element concentrations were elevated when the air mass came from the south.

  2. Novel biogeochemical fingerprinting approaches to sediment source apportionment in catchments (Invited)

    Science.gov (United States)

    Dungait, J.; Puttock, A.; Beniston, J. W.; Brazier, R. E.; Lal, R.; Collins, A.

    2013-12-01

    Apportioning the source of organic carbon in eroding sediments is important to constrain the scale of transport processes and to assess the impact of anthropogenic activity on environmental quality. Established biogeochemical techniques are used to trace organic inputs typically derived directly or indirectly from plants into soils, sediments and water using lipid biomarkers. Recently, advances in bulk and compound specific stable 13C isotope analyses have provided novel ways of exploring the source and residence times of organic matter in soils using the natural abundance stable 13C isotope signature of C3 and C4 plant end member values. However, the application of biogeochemical source tracing technologies at the molecular level at field to catchment scales has been slow to develop because of perceived problems with dilution of molecular-scale signals. This paper describes the results of recent experiments in natural and agricultural environments in the UK (Collins et al., 2013; Dungait et al., 2013) and United States (Puttock et al., 2012; Beniston et al., submitted) that have successfully applied new biogeochemical fingerprinting techniques using stable 13C isotope approaches and complementary modelling approaches to explore the transport of particulate and sediment-bound organic carbon at a range of scales from the small plot (m2) to field (ha) and small catchment (10's ha). References Beniston et al (submitted) The effects of crop residue removal on soil erosion and macronutrient dynamics on soils under no till for 42 years. Biogeosciences Collins et al (2013) Catchment source contributions to the sediment-bound organic matter degrading salmonid spawning gravels in a lowland river, southern England. Science of the Total Environment 456-457, 181-195. Dungait et al (2013) Microbial responses to the erosional redistribution of soil organic carbon in arable fields. Soil Biology and Biochemistry 60, 195-201. Puttock et al (2012) Stable carbon isotope analysis of fluvial sediment fluxes over two contrasting C4-C3 semi-arid vegetation transitions. Rapid Communications in Mass Spectrometry 26, 2386-2392

  3. Source apportionment of polycyclic aromatic hydrocarbons (PAHs) in sediments from Khuzestan province, Iran

    DEFF Research Database (Denmark)

    Lübeck, Josephine; Poulsen, Kristoffer Gulmark; Knudsen, Sofie B.;

    2016-01-01

    Khuzestan, Iran is heavily industrialised with petrochemical and refinery companies. Herein, sediment and soil samples were collected from Hendijan coast, Khore Mosa and Arvandroud River. The CHEMSIC (CHEmometric analysis of Selected Ion Chromatograms) method was used to assign the main sources...... of polycyclic aromatic hydrocarbon (PAH) pollution. A four-component principal component analysis (PCA) model was obtained. While principal component 1 (PC1) was related to the total concentration of PAHs, the remaining PCs described three distinct sources: PC2 and PC3 collectively differentiate between...... weathered petrogenic and pyrogenic, and PC4 is indicative for a diagenetic input. The sources of PAHs in the Arvandroud River were mainly relatively fresh oil with some samples corresponding to a weathered oil input. Further, perylene (indicator for diagenetic source) was identified. Samples from Khore Mosa...

  4. Source apportionment and location by selective wind sampling and Positive Matrix Factorization.

    Science.gov (United States)

    Venturini, Elisa; Vassura, Ivano; Raffo, Simona; Ferroni, Laura; Bernardi, Elena; Passarini, Fabrizio

    2014-10-01

    In order to determine the pollution sources in a suburban area and identify the main direction of their origin, PM2.5 was collected with samplers coupled with a wind select sensor and then subjected to Positive Matrix Factorization (PMF) analysis. In each sample, soluble ions, organic carbon, elemental carbon, levoglucosan, metals, and Polycyclic Aromatic Hydrocarbons (PAHs) were determined. PMF results identified six main sources affecting the area: natural gas home appliances, motor vehicles, regional transport, biomass combustion, manufacturing activities, and secondary aerosol. The connection of factor temporal trends with other parameters (i.e., temperature, PM2.5 concentration, and photochemical processes) confirms factor attributions. PMF analysis indicated that the main source of PM2.5 in the area is secondary aerosol. This should be mainly due to regional contributions, owing to both the secondary nature of the source itself and the higher concentration registered in inland air masses. The motor vehicle emission source contribution is also important. This source likely has a prevalent local origin. The most toxic determined components, i.e., PAHs, Cd, Pb, and Ni, are mainly due to vehicular traffic. Even if this is not the main source in the study area, it is the one of greatest concern. The application of PMF analysis to PM2.5 collected with this new sampling technique made it possible to obtain more detailed results on the sources affecting the area compared to a classical PMF analysis. PMID:24488520

  5. [Composition and Source Apportionments of Saccharides in Atmospheric Particulate Matter in Beijing].

    Science.gov (United States)

    Liang, Lin-lin; Guenter, Engling; Duan, Feng-kui; Ma, Yong-liang; Cheng, Yuan; Du, Zhen-yu; He, Ke-bin

    2015-11-01

    Based on the newly established high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD), the saccharides in PM2.5 and PM10 in Beijing from 2011 - 2012 were quantified. Fourteen saccharides were synchronously detected in the aerosols samples in Beijing, which can be divided into three categories, i. e. anhydrosugar, sugar and sugar alcohol. Anhydrosugar, coming from biomass burning, include levoglucosan, mannosan and galactosan. Sugar and sugar alcohol, emitted by the primary biogenic emission, include glucose, fructose, trehalose, arabitol, mannitol, glycerol, threitol, 2-meythltrtols (2-methylthreitol and 2-methylerythrito), xylitol and inositol. The concentrations of monosaccharide anhydrides in summer and autumn were obviously higher than those in spring and winter, while the concentrations of sugar and sugar alcohol in winter were significantly lower than those in other seasons. The results of positive matrix factorization analysis suggested that saccharides compounds in atmospheric PM in Beijing can be derived from biomass burning, suspended soil or dust, isoprene SOA, as well as direct release of airborne fungal spores and pollen. PMID:26910976

  6. Chemical characterization of fine organic aerosol for source apportionment at Monterrey, Mexico

    Science.gov (United States)

    Mancilla, Y.; Mendoza, A.; Fraser, M. P.; Herckes, P.

    2015-07-01

    Primary emissions from anthropogenic and biogenic sources as well as secondary formation are responsible for the pollution levels of ambient air in major urban areas. These sources release fine particles into the air that negatively impact human health and the environment. Organic molecular markers, which are compounds that are unique to specific PM2.5 sources, can be utilized to identify the major emission sources in urban areas. In this study, 43 representative PM2.5 samples, for both daytime and nighttime periods, were built from individual samples collected in an urban site of the Monterrey Metropolitan Area (MMA) during the spring and fall of 2011 and 2012. The samples were analyzed for organic carbon, elemental carbon, and organic molecular markers. Several diagnostic tools were employed for the preliminary identification of emission sources. Organic compounds for eight compound classes were quantified. The n-alkanoic acids were the most abundant, followed by n-alkanes, wood smoke markers, and levoglucosan/alkenoic acids. Polycyclic aromatic hydrocarbons (PAHs) and hopanes were less abundant. The carbon preference index (0.7-2.6) for n-alkanes indicate a major contribution of anthropogenic and mixed sources during the fall and the spring, respectively. Hopanes levels confirmed the contribution from gasoline and diesel engines. In addition, the contribution of gasoline and diesel vehicle exhaust was confirmed and identified by the PAH concentrations in PM2.5. Diagnostic ratios of PAH showed emissions from burning coal, wood, biomass, and other fossil fuels. The total PAH and elemental carbon (EC) were correlated (r2 = 0.39-0.70) across the monitoring periods, reinforcing that motor vehicles are the major contributors of PAH. Cholesterol levels remained constant during the spring and fall, showing evidence of the contribution of meat cooking operations, while the isolated concentrations of levoglucosan suggested occasional biomass burning events. Finally, source attribution results obtained using the CMB model indicate that emissions from motor vehicle exhausts are the most important, accounting for the 64 % of the PM2.5. The vegetative detritus and biomass burning had the smallest contribution (2.2 % of the PM2.5). To our knowledge, this is the second study to explore the broad chemical characterization of fine organic aerosol in Mexico and the first for the MMA.

  7. Apportionment of urban aerosol sources in Cork (Ireland) by synergistic measurement techniques.

    Science.gov (United States)

    Dall'Osto, Manuel; Hellebust, Stig; Healy, Robert M; O'Connor, Ian P; Kourtchev, Ivan; Sodeau, John R; Ovadnevaite, Jurgita; Ceburnis, Darius; O'Dowd, Colin D; Wenger, John C

    2014-09-15

    The sources of ambient fine particulate matter (PM2.5) during wintertime at a background urban location in Cork city (Ireland) have been determined. Aerosol chemical analyses were performed by multiple techniques including on-line high resolution aerosol time-of-flight mass spectrometry (Aerodyne HR-ToF-AMS), on-line single particle aerosol time-of-flight mass spectrometry (TSI ATOFMS), on-line elemental carbon-organic carbon analysis (Sunset_EC-OC), and off-line gas chromatography/mass spectrometry and ion chromatography analysis of filter samples collected at 6-h resolution. Positive matrix factorization (PMF) has been carried out to better elucidate aerosol sources not clearly identified when analyzing results from individual aerosol techniques on their own. Two datasets have been considered: on-line measurements averaged over 2-h periods, and both on-line and off-line measurements averaged over 6-h periods. Five aerosol sources were identified by PMF in both datasets, with excellent agreement between the two solutions: (1) regional domestic solid fuel burning--"DSF_Regional," 24-27%; (2) local urban domestic solid fuel burning--"DSF_Urban," 22-23%; (3) road vehicle emissions--"Traffic," 15-20%; (4) secondary aerosols from regional anthropogenic sources--"SA_Regional" 9-13%; and (5) secondary aged/processed aerosols related to urban anthropogenic sources--"SA_Urban," 21-26%. The results indicate that, despite regulations for restricting the use of smoky fuels, solid fuel burning is the major source (46-50%) of PM2.5 in wintertime in Cork, and also likely other areas of Ireland. Whilst wood combustion is strongly associated with OC and EC, it was found that peat and coal combustion is linked mainly with OC and the aerosol from these latter sources appears to be more volatile than that produced by wood combustion. Ship emissions from the nearby port were found to be mixed with the SA_Regional factor. The PMF analysis allowed us to link the AMS cooking organic aerosol factor (AMS_PMF_COA) to oxidized organic aerosol, chloride and locally produced nitrate, indicating that AMS_PMF_COA cannot be attributed to primary cooking emissions only. Overall, there are clear benefits from factor analysis applied to results obtained from multiple techniques, which allows better association of aerosols with sources and atmospheric processes.

  8. 76 FR 6957 - FTA Fiscal Year 2011 Apportionments, Allocations, and Program Information

    Science.gov (United States)

    2011-02-08

    ... service equal to or above the industry average level of service for all UZAs with a population of at least... was the case under the Transportation Equity Act for the 21st Century (TEA-21). Designated recipients... operating costs related to its passenger operations. (4) Section 3027(c)(3) of TEA-21, as amended (49...

  9. Chemical mass balance source apportionment of fine and PM10 in the Desert Southwest, USA

    Directory of Open Access Journals (Sweden)

    Andrea L. Clements

    2016-03-01

    Full Text Available The Desert Southwest Coarse Particulate Matter Study was undertaken in Pinal County, Arizona, to better understand the origin and impact of sources of fine and coarse particulate matter (PM in rural, arid regions of the U.S. southwestern desert. The desert southwest experiences some of the highest PM10 mass concentrations in the country. To augment previously reported results, 6-week aggregated organic speciation data that included ambient concentrations of n-alkanes, polycyclic aromatic hydrocarbons, organic acids, and saccharides were used in chemical mass balance modeling (CMB. A set of re-suspended soil samples were analyzed for specific marker species to provide locally-appropriate source profiles for the CMB analysis. These profiles, as well as previously collected plant and fungal spore profiles from the region, were combined with published source profiles for other relevant sources and used in the CMB analysis. The six new region-specific source profiles included both organic and inorganic species for four crustal material sources, one plant detritus source, and one fungal spore source.Results indicate that up to half of the ambient PM2.5 was apportioned to motor vehicles with the highest regional contribution observed in the small urban center of Casa Grande. Daily levels of apportioned crustal material accounted for up to 50% of PM2.5 mass with the highest contributions observed at the sites closest to active agricultural areas. Apportioned secondary PM, biomass burning, and road dust typically contributed less than 35% as a group to the apportioned PM2.5 mass. Crustal material was the primary source apportioned to PM10 and accounted for between 50–90% of the apportioned mass. Of the other sources apportioned to PM10, motor vehicles and road dust were the largest contributors at the urban and one of the rural sites, whereas road dust and meat cooking operations were the largest contributors at the other rural site.

  10. Source apportionment of fine organic aerosol in Mexico City during the MILAGRO Experiment 2006

    Directory of Open Access Journals (Sweden)

    E. A. Stone

    2007-07-01

    Full Text Available Organic carbon (OC comprises a large fraction of fine particulate matter (PM2.5 in Mexico City. Daily and select 12-h PM2.5 samples were collected in urban and peripheral sites in Mexico City from 17–30 March 2006. Samples were analyzed for OC and elemental carbon (EC using thermal-optical filter-based methods. Real-time water-soluble organic carbon (WSOC was collected at the peripheral site. Organic compounds, particularly molecular markers, were quantified by soxhlet extraction with methanol and dichloromethane, derivitization, and gas chromatography with mass spectrometric detection (GCMS. A chemical mass balance model (CMB based on molecular marker species was used to determine the relative contribution of major sources to ambient OC. Motor vehicles, including diesel and gasoline, consistently accounted for 47% of OC in the urban area and 31% on the periphery. The daily contribution of biomass burning to OC was highly variable, and ranged from 5–30% at the urban site and 11–50% at the peripheral site. The remaining OC unapportioned to primary sources showed a strong correlation with WSOC and was considered to be secondary in nature. Comparison of temporally resolved OC showed that contributions from primary aerosol sources during daylight hours were not significantly different from nighttime. This study provides quantitative understanding of the important sources of OC during the MILAGRO 2006 field campaign.

  11. Source apportionment of fine organic aerosol in Mexico City during the MILAGRO experiment 2006

    Directory of Open Access Journals (Sweden)

    E. A. Stone

    2008-03-01

    Full Text Available Organic carbon (OC comprises a large fraction of fine particulate matter (PM2.5 in Mexico City. Daily and select 12-h PM2.5 samples were collected in urban and peripheral sites in Mexico City from 17–30 March 2006. Samples were analyzed for OC and elemental carbon (EC using thermal-optical filter-based methods. Real-time water-soluble organic carbon (WSOC was collected at the peripheral site. Organic compounds, particularly molecular markers, were quantified by soxhlet extraction with methanol and dichloromethane, derivitization, and gas chromatography with mass spectrometric detection (GCMS. A chemical mass balance model (CMB based on molecular marker species was used to determine the relative contribution of major sources to ambient OC. Motor vehicles, including diesel and gasoline, consistently accounted for 49% of OC in the urban area and 32% on the periphery. The daily contribution of biomass burning to OC was highly variable, and ranged from 5–26% at the urban site and 7–39% at the peripheral site. The remaining OC unapportioned to primary sources showed a strong correlation with WSOC and was considered to be secondary in nature. Comparison of temporally resolved OC showed that contributions from primary aerosol sources during daylight hours were not significantly different from nighttime. This study provides quantitative understanding of the important sources of OC during the MILAGRO 2006 field campaign.

  12. 75 FR 7047 - FTA Fiscal Year 2010 Apportionments, Allocations, and Program Information

    Science.gov (United States)

    2010-02-16

    ... American families in rural, suburban and urban areas. During FY 2010, FTA will implement the Livability Bus... (SAFETEA-LU) and the Transportation, Housing and Urban Development, and Related Agencies Appropriations Act...) 2009. Additionally, Division A of the Transportation, Housing and Urban Development, and...

  13. Source apportionment of atmospheric mercury pollution in China using the GEOS-Chem model

    International Nuclear Information System (INIS)

    China is the largest atmospheric mercury (Hg) emitter in the world. Its Hg emissions and environmental impacts need to be evaluated. In this study, China's Hg emission inventory is updated to 2007 and applied in the GEOS-Chem model to simulate the Hg concentrations and depositions in China. Results indicate that simulations agree well with observed background Hg concentrations. The anthropogenic sources contributed 35–50% of THg concentration and 50–70% of total deposition in polluted regions. Sensitivity analysis was performed to assess the impacts of mercury emissions from power plants, non-ferrous metal smelters and cement plants. It is found that power plants are the most important emission sources in the North China, the Yangtze River Delta (YRD) and the Pearl River Delta (PRD) while the contribution of non-ferrous metal smelters is most significant in the Southwest China. The impacts of cement plants are significant in the YRD, PRD and Central China. - Highlights: • China's anthropogenic mercury emission was 643.1 t in 2007. • GEOS-Chem model well reproduces the background Hg concentrations. • Anthropogenic emissions contribute 35–50% of Hg concentrations in polluted regions. • The priorities for mercury control in polluted regions are identified. - Anthropogenic Hg emissions are updated and their impacts on atmospheric mercury concentrations and depositions are quantified for China

  14. [Distribution and source apportionment of polycyclic aromatic hydrocarbons (PAHs) in urban rainfall runoff].

    Science.gov (United States)

    Wu, Zi-Lan; Yang, Yi; Liu, Min; Lu, Min; Yu, Ying-Peng; Wang, Qing; Zheng, Xin

    2014-11-01

    Runoff samples were collected from traffic roads, campus, residential road and roof in a typical rain event. Polycyclic aromatic hydrocarbons (PAHs) in both dissolved and particle phases were investigated at impervious surfaces. The PAHs wash-off process at different monitoring sites was analyzed. The scatters of first flush were conducted in a method of fitting power function to quantitatively assess the magnitude of first flush effect (FFE). The sources of PAHs were identified using factor analysis. The results showed that PAHs concentrations in runoff samples varied from 317.21 ng x L(-1) to 10364.3 ng x L(-1) with the maximal and minimal contents of PAHs found on Longwu Road and campus, respectively. The values of event mean concentration ( EMC) varied considerably at different sampling sites. The concentration of washed-off pollutant generally decreased with runoff duration, which showed an obvious attenuation trend. The runoff process indicated the occurrence of FFE at different levels. PAHs mainly came from the incomplete combustion of fossil fuels, oil leakage and coking, and the contribution of each source was different in accordance with various surfaces.

  15. PM2.5 in an industrial district of Zhengzhou, China: Chemical composition and source apportionment

    Institute of Scientific and Technical Information of China (English)

    Ningbo Geng; Jia Wang; Yifei Xu; Wending Zhang; Chun Chen; Ruiqin Zhang

    2013-01-01

    Zhengzhou is a developing city in China,that is heavily polluted by high levels of particulate matter.In this study,fine particulate matter (PM2.5) was collected and analyzed for their chemical composition (soluble ions,elements,elemental carbon (EC) and organic carbon (OC)) in an industrial district of Zhengzhou in 2010.The average concentrations of PM2.5 were 181,122,186 and 211 μg/m3 for spring,summer,autumn and winter,respectively,with an annual average of 175 μg/m3,far exceeding the PM2.5 regulation of USA National Air Quality Standards (15 μg/m3).The dominant components of PM2.5 in Zhengzhou were secondary ions (sulphate and nitrate) and carbon fractions.Soluble ions,total carbon and elements contributed 41%,13% and 3% of PM2.5 mass,respectively.Soil dust,secondary aerosol and coal combustion,each contributing about 26%,24% and 23% of total PM2.5 mass,were the major sources of PM2.5,according to the result of positive matrix factorization analysis.A mixed source of biomass burning,oil combustion and incineration contributed 13% of PM2.5.Fine particulate matter arising from vehicles and industry contributed about 10% and 4% of PM2.5,respectively.

  16. 26 CFR 1.861-17 - Allocation and apportionment of research and experimental expenditures.

    Science.gov (United States)

    2010-04-01

    ... be sold in the nearest market but only some of which may be sold in foreign markets. Second, research... of evaluating the delay in the application of research findings in foreign markets, the taxpayer... the funding of all of X's research activity. In 1997, corporation Z has sales in country Z equal to...

  17. Ambient particle source apportionment and daily hospital admissions among children and elderly in Copenhagen

    DEFF Research Database (Denmark)

    Andersen, Zorana Jovanovic; Wahlin, P.; Raaschou-Nielsen, Ole;

    2007-01-01

    An association between particulate air pollution and morbidity and mortality is well established. However, little is known about which sources of particulate matter contribute most to the adverse health effects. Identification of responsible sources would merit more efficient control. For a 6-year...... period (01 January 1999 to 31 December 2004), we examined associations between urban background PM(10) in the presence of gaseous pollutants (CO, NO(2)) and hospital admissions due to cardiovascular and respiratory disease in the elderly (age>/=65), and asthma in children (age 5-18) in Copenhagen......, Denmark. We further studied associations between fractions of PM(10) assigned to six sources (biomass, secondary, oil, crustal, sea salt, and vehicle) and admissions during a 1(1/2) -year campaign. We used Poisson generalized additive time-series model adjusted for season, day of the week, public holidays...

  18. [Chemical Compositions and Sources Apportionment of Re-suspended Dust in Jincheng].

    Science.gov (United States)

    Wang, Yan; Peng, Lin; Li, Li-juan; Zhang, Teng; Liu, Hai-li; Mu, Ling

    2016-01-15

    In order to make effective plan to provide the scientific basis for prevention and control of re-suspended dust (RD), samples of particulate sources including RD and other pollution sources of Jincheng were collected. Elements, ions and carbon in particulate sources were analyzed. Enrichment factor, potential ecological risk assessment, and chemical mass balance model were used to analyze the chemical composition and the source of RD. The result indicated that the main components in RD of Jingeheng were Si, TC, Ca, OC, Al, Mg, Na, Fe, K and SO4(2-), contributing 61.14% of total mass of RD. The most abundant content of RD was crustal elements, and the ions were enriched in the fine particles. The mass fraction of OC in PM2. was higher, whereas the mass fraction of EC in PM10 was higher, indicating that secondary organic pollutants were mainly dominated in the fine particles. The dust PM2.5 and PM10 potential ecological risk indexes were extremely strong, and PM2.5 had higher ecological harm than PM10. Pb had the highest enrichment factor of 196.97 in PM2.5, which was followed by As, Cr, Ni, V, Zn and Cu, the enrichment factors of which were all greater than 10, indicating that they were apparently enriched and affected by human activities. Soil dust, construction dust, vehicle exhaust, and coal dust were the main sources of RD. PMID:27078944

  19. Carbonaceous aerosols and pollutants over Delhi urban environment: Temporal evolution, source apportionment and radiative forcing

    Energy Technology Data Exchange (ETDEWEB)

    Bisht, D.S. [Indian Institute of Tropical Meteorology, New Delhi (India); Dumka, U.C., E-mail: dumka@aries.res.in [Aryabhatta Research Institute of Observational Sciences, Nainital (India); Kaskaoutis, D.G. [School of Natural Sciences, Shiv Nadar University, Tehsil Dadri (India); Pipal, A.S. [Department of Chemistry, Savitribai Phule Pune University, Pune (India); Srivastava, A.K. [Indian Institute of Tropical Meteorology, New Delhi (India); Soni, V.K.; Attri, S.D.; Sateesh, M. [India Meteorology Department, Lodhi Road, New Delhi (India); Tiwari, S. [Indian Institute of Tropical Meteorology, New Delhi (India)

    2015-07-15

    Particulate matter (PM{sub 2.5}) samples were collected over Delhi, India during January to December 2012 and analysed for carbonaceous aerosols and inorganic ions (SO{sub 4}{sup 2−} and NO{sub 3}{sup −}) in order to examine variations in atmospheric chemistry, combustion sources and influence of long-range transport. The PM{sub 2.5} samples are measured (offline) via medium volume air samplers and analysed gravimetrically for carbonaceous (organic carbon, OC; elemental carbon, EC) aerosols and inorganic ions (SO{sub 4}{sup 2−} and NO{sub 3}{sup −}). Furthermore, continuous (online) measurements of PM{sub 2.5} (via Beta-attenuation analyser), black carbon (BC) mass concentration (via Magee scientific Aethalometer) and carbon monoxide (via CO-analyser) are carried out. PM{sub 2.5} (online) range from 18.2 to 500.6 μg m{sup −3} (annual mean of 124.6 ± 87.9 μg m{sup −3}) exhibiting higher night-time (129.4 μg m{sup −3}) than daytime (103.8 μg m{sup −3}) concentrations. The online concentrations are 38% and 28% lower than the offline during night and day, respectively. In general, larger night-time concentrations are found for the BC, OC, NO{sub 3}{sup −}and SO{sub 4}{sup 2−}, which are seasonally dependent with larger differences during late post-monsoon and winter. The high correlation (R{sup 2} = 0.74) between OC and EC along with the OC/EC of 7.09 (day time) and 4.55 (night-time), suggest significant influence of biomass-burning emissions (burning of wood and agricultural waste) as well as secondary organic aerosol formation during daytime. Concentrated weighted trajectory (CWT) analysis reveals that the potential sources for the carbonaceous aerosols and pollutants are local emissions within the urban environment and transported smoke from agricultural burning in northwest India during post-monsoon. BC radiative forcing estimates result in very high atmospheric heating rates (~ 1.8–2.0 K day{sup −1}) due to agricultural burning effects during the 2012 post-monsoon season. - Highlights: • Very high PM{sub 2.5} (> 200 µg m{sup −3}) levels over Delhi during agricultural burning period. • Enhanced levels of carbonaceous, sulphate and nitrate aerosol. • OC/EC suggests dominance of biomass burning and SOA formation. • BC highly contributes (50~70%) to the aerosol radiative forcing.

  20. Modeling geochemical datasets for source apportionment: Comparison of least square regression and inversion approaches.

    Digital Repository Service at National Institute of Oceanography (India)

    Tripathy, G.R.; Das, Anirban.

    in the field of Earth sciences to study and infer about various geological processes. Chemical, mineralogical and isotopic compositions of geological samples hold clues to the sources contributing to them and their mixing proportions and thus, provide useful... the maximum likelihood for data and model parameters within their covariances that maximizes the σM(m). The Quasi-Newton optimization method for non-linear relations, which relies on the iterative algorithm that starts the iteration from the a...

  1. Applications of lead isotope rations for identification and apportionment on pollution sources in food

    International Nuclear Information System (INIS)

    Lead is one of the toxic heavy metals which can accumulate to an adverse effect level in human bodies through ingestion, inhalation or other pathways. Because of the persistent lead contamination in farmland environment, large risk exists in the primary stage of 'from farm to table' chain. Environmental media such as soils, atmospheric aerosols were the possible lead sources of agro-food. To pinpoint the pollution sources exactly, cut off the contamination pathways in time, and reduce the risk of hazard, pollution sources tracing was very important. Lead isotope ratio combined with certain models is an effective method to discriminate correctly pollution sources and calculate the individual source contributions. In this review, to provide theoretical and technical reference for controlling lead pollution in environment and food, lead pollution sources in food, tracing principle and methods of lead isotope ratios, and its applications on vegetable, tea, wine, cereal and other food products were concerned. (authors)

  2. Currents trends in the application of IBA techniques to air pollution source fingerprinting and source apportionment

    International Nuclear Information System (INIS)

    Full text: IBA techniques have been used for many years to characterise fine particle air pollution. This is not new the techniques are well established. Typically 2-3 MeV protons are used to bombard thin filter papers and up to four simultaneous techniques like PIXE, PIGE, RBS and ERDA will be applied to obtain (μg/g) concentrations for elements from hydrogen to lead. Generally low volume samplers are used to sample between 20-30 m3 of air over a 24 hour period, this together with IBA's sensitivity means that concentrations down to 1 ng/m3 of air sampled can be readily achieved with only a few minutes of proton irradiation. With these short irradiation times and low sensitivities for a broad range of elements in the periodic table, large numbers of samples can be obtained and analysed very quickly and easily. At ANSTO we have used IBA methods to acquire a database of over 50,000 filters from 85 different sites through Australia and Asia, each filter has been analysed for more than 21 different chemical species. Large databases extending over many years means that modern statistical techniques like positive matrix factorisation (PMF) can be used to define well characterised source fingerprints and source contributions for a range of different fine particle air pollutants. In this paper we will discuss these PMF techniques and show how they identify both natural sources like sea spray and windblown soils as well as anthropogenic sources like automobiles, biomass burning, coal-fired power stations and industrial emissions. These data are particularly useful for Governments, EPA's and managers of pollution to better understanding pollution sources and their relative contributions and hence to better manage air pollution. Current trends are to take these IBA and PMF techniques a step further and to combine them with wind speed and back trajectory data to better pin point and identify emission sources. We show how this is now being applied on both a local, regional and global scale with examples of local industrial pollution in urban areas and with long range air pollution being tracked from China into Vietnam. (author)

  3. Distribution and source apportionment studies of heavy metals in soil of cotton/wheat fields.

    Science.gov (United States)

    Rafique, Nazia; Tariq, Saadia R

    2016-05-01

    Heavy metals enriched agricultural soils have been the subject of great concern because these metals have potential to be transferred to the soil solution and afterward accumulated in food chain. To study the trace metal persistence in crop soil, 90 representative soil samples were collected and analyzed for heavy metal (As, Cd, Cu, Fe, Mn, Ni, Pb, and Zn) and anions (chloride, nitrates, phosphates and sulfates). Cluster and factor analysis techniques were used for the source identification of these excessive heavy metal levels and ecological risk was determined with potential ecological risk assessment. The degree of enrichment of eight studied heavy metals in comparison with the corresponding background levels decreased in order: Cd > Pb > Fe > Ni > Mn > As > Cu ~ Zn. Arsenic and cadmium exhibited 1.30- and 1.64-fold exceeded levels than threshold limits set by National environment quality standards, respectively. Cd in cotton field's soil may lead to higher potential risk than other heavy metals. On overall basis, the cumulative mean potential ecological risk for the district (207.75) corresponded to moderate risk level with higher contributions from As and Pb especially from Cd. Cadmium formed strong positive correlation with phosphate content of soil at p pesticides. PMID:27115422

  4. Size distribution, mixing state and source apportionments of black carbon aerosols in London during winter time

    Directory of Open Access Journals (Sweden)

    D. Liu

    2014-06-01

    Dc distributions and coating thicknesses, with BCsf displaying larger Dc and larger coating thickness compared to BCtr. BC particles from different sources were also apportioned by applying a multiple linear regression between the total BC mass and each AMS-PMF factor (BC-AMS-PMF method, and also attributed by applying the absorption spectral dependence of carbonaceous aerosols to 7-wavelength Aethalometer measurements (Aethalometer method. Air masses that originated from westerly (W, southeasterly (SE, or easterly (E sectors showed BCsf fractions that ranged from low to high, and whose mass median Dc values were 137 ± 10 nm, 143 ± 11 nm, and 169 ± 29 nm respectively. The corresponding bulk relative coating thickness of BC (coated particle size / BC core – Dp / Dc for these same sectors was 1.28 ± 0.07, 1.45 ± 0.16, and 1.65 ± 0.19. For W, SE and E air masses, the number fraction of BCsf ranged from 6 ± 2% to 11 ± 5% to 18 ± 10% respectively, but importantly the larger BC core sizes lead to an increased fraction of BCsf in terms of mass than number (for W–SE–E air masses, the BCsf mass fractions ranged from 16 ± 6 %–24 ± 10%–39 ± 14% respectively. An increased fraction of non-BC particles (particles that did not contain a BC core was also observed when SF sources were more significant. The BC mass attribution by the SP2 method agreed well with the BC-AMS-PMF multiple linear regression method (BC-AMS-PMF : SP2 ratio = 1.05, r2 = 0.80 over the entire experimental period. Good agreement was found between BCsf attributed with the Aethalometer model and the SP2. However, the assumed Absorption Ångström Exponent (αwb had to be changed according to the different air mass sectors to yield the best comparison with the SP2. This could be due to influences of fuel type or burn phase.

  5. Source apportionment of single aerosol particles in the atmosphere of Shanghai city

    International Nuclear Information System (INIS)

    A nuclear microprobe with high spatial resolution and high analytical sensitivity was applied to analyze atmospheric aerosol at five monitoring sites in Shanghai city. Meantime, a new pattern recognition technique, which used the micro-PIXE spectrum of a single aerosol particle as its fingerprint, was developed to identify the origin of the particle. The results showed that the major contributors to the atmosphere pollution were soil dust (31.6%), building dust (30.8%), and the next were vehicle exhaust (13.7%), metallurgic industry excrements (5.6%), oil combustion (5%) and coal combustion (2.3%). Besides these, about 10% of the particles could not be identified. Based on the cluster analysis of these particles, they could be divided into soil dust, building dust and metallurgic industry excrements. Moreover, some new pollution sources from tyres and chemical plants were also revealed

  6. Source apportionment of size segregated fine/ultrafine particle by PMF in Beijing

    Science.gov (United States)

    Tan, Ji-hua; Duan, Jing-chun; Chai, Fa-he; He, Ke-bin; Hao, Ji-Ming

    2014-03-01

    Considering the adverse health effects to human body, the number concentration of atmospheric PM (particulate material) is more important than the mass concentration. CO, NO, NO2, SO2 and number concentrations of PM were obtained from a remote site (Miyun), a roadside site (North Fourth Ring Road) and an urban residential site (Tsinghua University) in Beijing in winter. The size distribution and the possible sources of number concentrations were examined using EPA PMF (positive matrix factorization) model. A data set of totally 9610 of number concentration with the size range of 0.028 μm to 0.948 μm was included in the PMF analysis. The highest total particle number, mass and area of fine particles concentrations were observed at the North Fourth Ring Road site and the lowest were observed at Miyun site. Four factors were identified at Miyun site, as Factor 1 and Factor 4 may be related to long distance transportation, and Factor 2 and Factor 3 may be assigned as coal combustion and locomotive emission nearby, respectively; three factors were identified at North Fourth Ring Road, of which Factor 1 and Factor 3 are traffic related and Factor 2 may be coal combustion related. Compared with Factor 1, the contributions of Factor 3 to NOx and SO2 were 4-5 times higher. Additionally, Factor 3 was also a major contributor to CO. It suggested that Factor 1 and Factor 3 had the same source emission of motor vehicle, but different engine types, fuel types or exhaust treatments. Three factors were identified at Tsinghua site, as Factor 1 may come from aging vehicle emission, and Factor 2 and Factor 3 may be coal combustion related.

  7. Modeling study of natural emissions, source apportionment, and emission control of atmospheric mercury

    Science.gov (United States)

    Shetty, Suraj K.

    Mercury (Hg) is a toxic pollutant and is important to understand its cycling in the environment. In this dissertation, a number of modeling investigations were conducted to better understand the emission from natural surfaces, the source-receptor relationship of the emissions, and emission reduction of atmospheric mercury. The first part of this work estimates mercury emissions from vegetation, soil and water surfaces using a number of natural emission processors and detailed (LAI) Leaf Area Index data from GIS (Geographic Information System) satellite products. East Asian domain was chosen as it contributes nearly 50% of the global anthropogenic mercury emissions into the atmosphere. The estimated annual natural mercury emissions (gaseous elemental mercury) in the domain are 834 Mg yr-1 with 462 Mg yr-1 contributing from China. Compared to anthropogenic sources, natural sources show greater seasonal variability (highest in simmer). The emissions are significant, sometimes dominant, contributors to total mercury emission in the regions. The estimates provide possible explanation for the gaps between the anthropogenic emission estimates based on activity data and the emission inferred from field observations in the regions. To understand the contribution of domestic emissions to mercury deposition in the United States, the second part of the work applies the mercury model of Community Multi-scale Air Quality Modeling system (CMAQ-Hg v4.6) to apportion the various emission sources attributing to the mercury wet and dry deposition in the 6 United States receptor regions. Contributions to mercury deposition from electric generating units (EGU), iron and steel industry (IRST), industrial point sources excluding EGU and IRST (OIPM), the remaining anthropogenic sources (RA), natural processes (NAT), and out-of-boundary transport (BC) in domain was estimated. The model results for 2005 compared reasonably well to field observations made by MDN (Mercury Deposition Network) and CAMNet (Canadian Atmospheric Mercury Measurement Network). The model estimated a total deposition of 474 Mg yr-1 to the CONUS (Contiguous United States) domain, with two-thirds being dry deposited. Reactive gaseous mercury contributed the most to 60% of deposition. Emission speciation distribution is a key factor for local deposition as contribution from large point sources can be as high as 75% near (coal combustion processes has attracted great attention due to its toxicity and the emission-control regulations and has lead to advancement in state-of-the-art control technologies that alleviate the impact of mercury on ecosystem and human health. This part of the work applies a sorption model to simulate adsorption of mercury in flue gases, onto a confined-bed of activated carbon. The model's performances were studied at various flue gas flow rates, inlet mercury concentrations and adsorption bed temperatures. The process simulated a flue gas, with inlet mercury concentration of 300 ppb, entering at a velocity of 0.3 m s-1 from the bottom into a fixed bed (inside bed diameter of 1 m and 3 m bed height; bed temperature of 25 °C) of activated carbon (particle size of 0.004 m with density of 0.5 g cm-3 and surface area of 90.25 cm2 g -1). The model result demonstrated that a batch of activated carbon bed was capable of controlling mercury emission for approximately 275 days after which further mercury uptake starts to decrease till it reaches about 500 days when additional control ceases. An increase in bed temperature significantly reduces mercury sorption capacity of the activated carbon. Increase in flue gas flow rate may result in faster consumption of sorption capacity initially but at a later stage, the sorption rate decreases due to reduced sorption capacity. Thus, overall sorption rate remains unaffected. The activated carbon's effective life (time to reach saturation) is not affected by inlet mercury concentration, implying that the designing and operation of a mercury sorption process can be done independently. The results provide quantitative indication for designing efficient confined-bed process to remove mercury from flue gases.

  8. Nitrate behaviors and source apportionment in an aquatic system from a watershed with intensive agricultural activities.

    Science.gov (United States)

    Lu, Lu; Cheng, Hongguang; Pu, Xiao; Liu, Xuelian; Cheng, Qianding

    2015-01-01

    Nitrate pollution in aquatic systems caused by intensive agricultural activities is a serious problem in the Sanjiang Plain. In this study, a dual isotope approach (δ(15)N-NO3(-) and δ(18)O-NO3(-)) was employed to identify potential nitrate sources (atmospheric deposition, AD; NO3(-) derived from soil organic matter nitrification, NS; NO3(-) derived from chemical fertilizer nitrification, NF; and manure and sewage, M&S) and transformation processes occurring in the Abujiao River watershed located in the Sanjiang Plain. The Bayesian model (stable isotope analysis in R, SIAR) was utilized to apportion the contribution of the potential sources. In this watershed, the nitrate concentrations in the surface water were low (mean ± SD = 1.15 ± 0.84 mg L(-1)), and were greatly influenced by precipitation and land use conditions during the two sampling periods (the high flow period, September; the low flow period, November). On the contrary, in the ground water, high NO3(-) concentrations were observed (7.84 ± 5.83 mg L(-1)) and no significant temporal variation in NO3(-) was found during the sampling periods. The sampled water δ(18)O-NO3(-) values suggest that the nitrification process was not the main N cycling process, because most of the measured δ(18)O-NO3(-) values were above the expected δ(18)O-NO3(-) from nitrification throughout the sampling periods. Both the chemical and isotopic characteristics indicated that the signs of de-nitrification were absent in the surface water. However, significant de-nitrification processes were observed in the ground water for all sample periods. Results from the SIAR model showed that source contributions differed significantly during the two sampling periods. During the high flow period, chemical fertilizers and soil N fertilizer equally contributed to the major sources of nitrate in the surface water. In contrast, manure and sewage sources dominated the source contribution during the low flow period (November). This study suggested that with the assessment of the behaviors and sources of NO3(-), effective nitrate reduction strategies and better management practices can be implemented to protect water quality. PMID:25418139

  9. 76 FR 2765 - Apportionments to Dependents and Payments to Fiduciaries and Incarcerated Beneficiaries

    Science.gov (United States)

    2011-01-14

    ... rewrite in plain language regulations governing VA compensation, pension, burial, and related benefits... of domiciliary or nursing home care. Both of these clarifications are based upon the plain language..., or 90 percent. Proposed Sec. 5.720(d) restates in plain language exceptions contained in Sec....

  10. Apportionment of urban aerosol sources in Chongqing (China) using synergistic on-line techniques

    Science.gov (United States)

    Chen, Yang; Yang, Fumo

    2016-04-01

    The sources of ambient fine particulate matter (PM2.5) during wintertime at a background urban location in Chongqing (southwestern China) have been determined. Aerosol chemical composition analyses were performed using multiple on-line techniques, such as single particle aerosol mass spectrometer (SPAMS) for single particle chemical composition, on-line elemental carbon-organic carbon analyzer (on-line OC-EC), on-line X-ray fluorescence (XRF) for elements, and in-situ Gas and Aerosol Compositions monitor (IGAC) for water-soluble ions in PM2.5. All the datasets from these techniques have been adjusted to a 1-h time resolution for receptor model input. Positive matrix factorization (PMF) has been used for resolving aerosol sources. At least six sources, including domestic coal burning, biomass burning, dust, traffic, industrial and secondary/aged factors have been resolved and interpreted. The synergistic on-line techniques were helpful for identifying aerosol sources more clearly than when only employing the results from the individual techniques. This results are useful for better understanding of aerosol sources and atmospheric processes.

  11. Source apportionment of single aerosol particles in the atmosphere of Shanghai city

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A nuclear microprobe with high spatial resolution and high analyti cal sensitivity was applied to analyze atmospheric aerosol at five monitoring sites in Shanghai city. Meantime, a new pattern recognition technique, which used the micro PIXE spectrum of a single aerosol particle as its fingerprint, was developed to identify the origin of the particle. The results showed that the major contributors to the at mosphere pollution were soil dust (31.6%), building dust (30.8%), and the next were vehicle exhaust (13.7%), metallurgic industry excrements (5.6%), oil combustion (5%) and coal combustion (2.3%). Besides these, about 10% of the particles could not be identified. Based on the cluster analysis of these particles, they could be divided into eight groups. By inference, they might belong to some sub-pollution sources from soil dust, building dust and metallurgic industry excrements. Moreover, some new pollution sources from tyres and chemical plants were also revealed.

  12. Spatial Distribution, Sources Apportionment and Health Risk of Metals in Topsoil in Beijing, China.

    Science.gov (United States)

    Sun, Chunyuan; Zhao, Wenji; Zhang, Qianzhong; Yu, Xue; Zheng, Xiaoxia; Zhao, Jiayin; Lv, Ming

    2016-07-20

    In order to acquire the pollution feature and regularities of distribution of metals in the topsoil within the sixth ring road in Beijing, a total of 46 soil samples were collected, and the concentrations of twelve elements (Nickel, Ni, Lithium, Li, Vanadium, V, Cobalt, Co, Barium, Ba, Strontium, Sr, Chrome, Cr, Molybdenum, Mo, Copper, Cu, Cadmium, Cd, Zinc, Zn, Lead, Pb) were analyzed. Geostatistics and multivariate statistics were conducted to identify spatial distribution characteristics and sources. In addition, the health risk of the analyzed heavy metals to humans (adult) was evaluated by an U.S. Environmental Protection Agency health risk assessment model. The results indicate that these metals have notable variation in spatial scale. The concentration of Cr was high in the west and low in the east, while that of Mo was high in the north and low in the south. High concentrations of Cu, Cd, Zn, and Pb were found in the central part of the city. The average enrichment degree of Cd is 5.94, reaching the standard of significant enrichment. The accumulation of Cr, Mo, Cu, Cd, Zn, and Pb is influenced by anthropogenic activity, including vehicle exhaustion, coal burning, and industrial processes. Health risk assessment shows that both non-carcinogenic and carcinogenic risks of selected heavy metals are within the safety standard and the rank of the carcinogenic risk of the four heavy metals is Cr > Co > Ni > Cd.

  13. Spatial Distribution, Sources Apportionment and Health Risk of Metals in Topsoil in Beijing, China

    Directory of Open Access Journals (Sweden)

    Chunyuan Sun

    2016-07-01

    Full Text Available In order to acquire the pollution feature and regularities of distribution of metals in the topsoil within the sixth ring road in Beijing, a total of 46 soil samples were collected, and the concentrations of twelve elements (Nickel, Ni, Lithium, Li, Vanadium, V, Cobalt, Co, Barium, Ba, Strontium, Sr, Chrome, Cr, Molybdenum, Mo, Copper, Cu, Cadmium, Cd, Zinc, Zn, Lead, Pb were analyzed. Geostatistics and multivariate statistics were conducted to identify spatial distribution characteristics and sources. In addition, the health risk of the analyzed heavy metals to humans (adult was evaluated by an U.S. Environmental Protection Agency health risk assessment model. The results indicate that these metals have notable variation in spatial scale. The concentration of Cr was high in the west and low in the east, while that of Mo was high in the north and low in the south. High concentrations of Cu, Cd, Zn, and Pb were found in the central part of the city. The average enrichment degree of Cd is 5.94, reaching the standard of significant enrichment. The accumulation of Cr, Mo, Cu, Cd, Zn, and Pb is influenced by anthropogenic activity, including vehicle exhaustion, coal burning, and industrial processes. Health risk assessment shows that both non-carcinogenic and carcinogenic risks of selected heavy metals are within the safety standard and the rank of the carcinogenic risk of the four heavy metals is Cr > Co > Ni > Cd.

  14. Source apportionment of atmospheric fine particulate matter collected at the Seney National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The trends in secondary organic aerosol at a remote location are studied using atmospheric fine particulate matter samples collected at Seney National Wildlife...

  15. Spatio-Temporal Variations and Source Apportionment of Water Pollution in Danjiangkou Reservoir Basin, Central China

    OpenAIRE

    Pan Chen; Lan Li; Hongbin Zhang

    2015-01-01

    Understanding the spatio-temporal variation and the potential source of water pollution could greatly improve our knowledge of human impacts on the environment. In this work, data of 11 water quality indices were collected during 2012–2014 at 10 monitoring sites in the mainstream and major tributaries of the Danjiangkou Reservoir Basin, Central China. The fuzzy comprehensive assessment (FCA), the cluster analysis (CA) and the discriminant analysis (DA) were used to assess the water pollutio...

  16. 40 CFR 82.6 - Apportionment of baseline consumption allowances for class I controlled substances.

    Science.gov (United States)

    2010-07-01

    ... 12,466 Dow Chemical Company, USA 8,170,561 E.I. DuPont de Nemours & Co 26,537 Elf Atochem, N.A 41...,355 Dow Chemical Company, USA 125,200,200 E.I. DuPont de Nemours & Co 2 IBM 2,026 ICI Americas, Inc 14... 1986 are apportioned chemical-specific baseline consumption allowances as set forth in paragraphs...

  17. 40 CFR 82.5 - Apportionment of baseline production allowances for class I controlled substances.

    Science.gov (United States)

    2010-07-01

    ..., Inc 7,873,615 Degussa Corporation 26,546 Dow Chemical Company, USA 18,987,747 E.I. DuPont de Nemours...,358 Vulcan Chemicals 21,931,987 (e) For Group V controlled substances: Methyl Chloroform Dow Chemical...Pont de Nemours & Co 4,176,000 (b) For Group II controlled substances: Halon-1211 Great Lakes...

  18. Source apportionment of atmospheric mercury pollution in China using the GEOS-Chem model.

    Science.gov (United States)

    Wang, Long; Wang, Shuxiao; Zhang, Lei; Wang, Yuxuan; Zhang, Yanxu; Nielsen, Chris; McElroy, Michael B; Hao, Jiming

    2014-07-01

    China is the largest atmospheric mercury (Hg) emitter in the world. Its Hg emissions and environmental impacts need to be evaluated. In this study, China's Hg emission inventory is updated to 2007 and applied in the GEOS-Chem model to simulate the Hg concentrations and depositions in China. Results indicate that simulations agree well with observed background Hg concentrations. The anthropogenic sources contributed 35-50% of THg concentration and 50-70% of total deposition in polluted regions. Sensitivity analysis was performed to assess the impacts of mercury emissions from power plants, non-ferrous metal smelters and cement plants. It is found that power plants are the most important emission sources in the North China, the Yangtze River Delta (YRD) and the Pearl River Delta (PRD) while the contribution of non-ferrous metal smelters is most significant in the Southwest China. The impacts of cement plants are significant in the YRD, PRD and Central China. PMID:24768744

  19. Source apportionment of polycyclic aromatic hydrocarbons in the Dahuofang Reservoir, Northeast China.

    Science.gov (United States)

    Lin, Tian; Qin, Yanwen; Zheng, Binghui; Li, Yuanyuan; Chen, Ying; Guo, Zhigang

    2013-01-01

    Polycyclic aromatic hydrocarbons (PAHs) in 24 surface sediments from the Dahuofang Reservoir (DHF), the largest man-made lake in Northeast China, were measured. The results showed that the concentrations of 16 US EPA priority PAHs in the sediments ranged from 323 to 912 ng/g dry weight with a mean concentration of 592 ± 139 ng/g. The PAH source contributions were estimated based on positive matrix factorization model. The coal combustion contributed to 31 % of the measured PAHs, followed by residential emissions (22%), biomass burning (21%), and traffic-related emissions (10%). Pyrogenic sources contributed ~84% of anthropogenic PAHs to the sediments, indicating that energy consumption release was a predominant contribution of PAH pollution in DHF. Compared with the results from the urban atmospheric PAHs in the region, there was a low contribution from traffic-related emissions in the sediments possibly due to the low mobility of the traffic-related derived 5+6-ring PAHs and their rapid deposition close to the urban area. PMID:22454050

  20. Chemical characteristics and source apportionment of atmospheric particles during heating period in Harbin, China

    Institute of Scientific and Technical Information of China (English)

    Likun Huang; Guangzhi Wang

    2014-01-01

    Atmospheric particles (total suspended particles (TSPs); particulate matter (PM) with particle size below 10 μm,PM10; particulate matter with particle size below 2.5 μm,PM2.5)were collected and analyzed during heating and non-heating periods in Harbin.The sources of PM10 and PM2.5 were identified by the chemical mass balance (CMB) receptor model.Results indicated that PM2.5/TSP was the most prevalent and PM2.5 was the main component of PM10,while the presence of PM10-100 was relatively weak.SC42-and NO3-concentrations were more significant than other ions during the heating period.As compared with the non-heating period,Mn,Ni,Pb,S,Si,Ti,Zn,As,Ba,Cd,Cr,Fe and K were relatively higher during the heating period.In particular,Mn,Ni,S,Si,Ti,Zn and As in PM2.5 were obviously higher during the heating period.Organic carbon (OC) in the heating period was 2-5 times higher than in the non-heating period.Elemental carbon (EC) did not change much.OC/EC ratios were 8-11 during the heating period,which was much higher than in other Chinese cities (OC/EC:4-6).Results from the CMB indicated that 11 pollution sources were identified,of which traffic,coal combustion,secondary sulfate,secondary nitrate,and secondary organic carbon made the greatest contnbution.Before the heating period,dust and petrochemical industry made a larger contribution.In the heating period,coal combustion and secondary sulfate were higher.After the heating period,dust and petrochemical industry were highen Some hazardous components in PM2.5 were higher than in PM10,because PM2.5 has a higher ability to absorb toxic substances.Thus PM2.5 pollution is more significant regarding human health effects in the heating period.

  1. Secondary organic carbon quantification and source apportionment of PM10 in Kaifeng, China

    Institute of Scientific and Technical Information of China (English)

    WU Lin; FENG Yinchang; WU Jianhui; ZHU Tan; BI Xiaohui; HAN Bo; YANG Weihong; YANG Zhiqiang

    2009-01-01

    During 2005, the filter samples of ambient PM10 from five sites and the source samples of particulate matter were collected in Kaifeng, Henan province of China. Nineteen elements, water-soluble ions, total carbon (TC) and organic carbon (OC) contained in samples were analyzed. Seven contributive source types were identified and their contributions to ambient PM10 were estimated by chemical mass balance (CMB) receptor model. Weak associations between the concentrations of organic carbon and element carbon (EC) were observed during the sampling periods, indicating that there was secondary organic aerosol pollution in the urban atmosphere. An indirect method of "OC/EC minimum ratio" was applied to estimate the concentration of secondary organic carbon (SOC). The results showed that SOC contributed 26.2%, 32.4% and 18.0% of TC in spring, summer-fall and winter respectively, and the annual average SOC concentration was 7.07 μg/m3, accounting for 5.73% of the total mass in ambient PM10. The carbon species concentrations in ambient PM10 were recalculated by subtracting the SOC concentrations from measured concentrations of TC and OC to increase the compatibility of source and receptor measurements for CMB model.

  2. Water Quality Assessment of River Soan (Pakistan) and Source Apportionment of Pollution Sources Through Receptor Modeling.

    Science.gov (United States)

    Nazeer, Summya; Ali, Zeshan; Malik, Riffat Naseem

    2016-07-01

    The present study was designed to determine the spatiotemporal patterns in water quality of River Soan using multivariate statistics. A total of 26 sites were surveyed along River Soan and its associated tributaries during pre- and post-monsoon seasons in 2008. Hierarchical agglomerative cluster analysis (HACA) classified sampling sites into three groups according to their degree of pollution, which ranged from least to high degradation of water quality. Discriminant function analysis (DFA) revealed that alkalinity, orthophosphates, nitrates, ammonia, salinity, and Cd were variables that significantly discriminate among three groups identified by HACA. Temporal trends as identified through DFA revealed that COD, DO, pH, Cu, Cd, and Cr could be attributed for major seasonal variations in water quality. PCA/FA identified six factors as potential sources of pollution of River Soan. Absolute principal component scores using multiple regression method (APCS-MLR) further explained the percent contribution from each source. Heavy metals were largely added through industrial activities (28 %) and sewage waste (28 %), nutrients through agriculture runoff (35 %) and sewage waste (28 %), organic pollution through sewage waste (27 %) and urban runoff (17 %) and macroelements through urban runoff (39 %), and mineralization and sewage waste (30 %). The present study showed that anthropogenic activities are the major source of variations in River Soan. In order to address the water quality issues, implementation of effective waste management measures are needed. PMID:27000830

  3. 75 FR 27056 - FTA Supplemental Fiscal Year 2010 Apportionments, Allocations, and Corrections

    Science.gov (United States)

    2010-05-13

    ..., Administrator. Appendix A FTA Regional and Metropolitan Offices Richard H. Doyle, Regional Robert C. Patrick...-3133. States served: Alabama, Florida, States served: American Samoa, Georgia, Kentucky,...

  4. Preliminary PM2.5 and PM10 fractions source apportionment complemented by statistical accuracy determination

    Directory of Open Access Journals (Sweden)

    Samek Lucyna

    2016-03-01

    Full Text Available Samples of PM10 and PM2.5 fractions were collected between the years 2010 and 2013 at the urban area of Krakow, Poland. Numerous types of air pollution sources are present at the site; these include steel and cement industries, traffic, municipal emission sources and biomass burning. Energy dispersive X-ray fluorescence was used to determine the concentrations of the following elements: Cl, K, Ca, Ti, Mn, Fe, Ni, Cu, Zn, Br, Rb, Sr, As and Pb within the collected samples. Defining the elements as indicators, airborne particulate matter (APM source profiles were prepared by applying principal component analysis (PCA, factor analysis (FA and multiple linear regression (MLR. Four different factors identifying possible air pollution sources for both PM10 and PM2.5 fractions were attributed to municipal emissions, biomass burning, steel industry, traffic, cement and metal industry, Zn and Pb industry and secondary aerosols. The uncertainty associated with each loading was determined by a statistical simulation method that took into account the individual elemental concentrations and their corresponding uncertainties. It will be possible to identify two or more sources of air particulate matter pollution for a single factor in case it is extremely difficult to separate the sources.

  5. Chemical mass balance source apportionment of fine and PM10 in the Desert Southwest, USA

    Science.gov (United States)

    The Desert Southwest Coarse Particulate Matter Study was undertaken in Pinal County, Arizona, to better understand the origin and impact of sources of fine and coarse particulate matter (PM) in rural, arid regions of the U.S. southwestern desert. The desert southwest experiences ...

  6. Source apportionment and health risk assessment of trace metals in surface soils of Beijing metropolitan, China.

    Science.gov (United States)

    Chen, Haiyang; Teng, Yanguo; Lu, Sijin; Wang, Yeyao; Wu, Jin; Wang, Jinsheng

    2016-02-01

    Understanding the exposure risks of trace metals in contamination soils and apportioning their sources are the basic preconditions for soil pollution prevention and control. In this study, a detailed investigation was conducted to assess the health risks of trace metals in surface soils of Beijing which is one of the most populated cities in the world and to apportion their potential sources. The data set of metals for 12 elements in 240 soil samples was collected. Pollution index and enrichment factor were used to identify the general contamination characteristic of soil metals. The probabilistic risk model was employed for health risk assessment, and a chemometrics technique, multivariate curve resolution-weighted alternating least squares (MCR-WALS), was applied to apportion sources. Results suggested that the soils in Beijing metropolitan region were contaminated by Hg, Cd, Cu, As, and Pb in varying degree, lying in the moderate pollution level. As a whole, the health risks posed by soil metals were acceptable or close to tolerable. Comparatively speaking, children and adult females were the relatively vulnerable populations for the non-carcinogenic and carcinogenic risks, respectively. Atmospheric deposition, fertilizers and agrochemicals, and natural source were apportioned as the potential sources determining the contents of trace metals in soils of Beijing area with contributions of 15.5%-16.4%, 5.9%-7.7% and 76.0%-78.6%, respectively.

  7. HVACMeter: Apportionment of HVAC Power to Thermal Zones and Air Handler Units

    OpenAIRE

    Koh, Jason; Balaji, Bharathan; Gupta, Rajesh; Agarwal, Yuvraj

    2015-01-01

    Heating, Ventilation and Air Conditioning (HVAC) systems consume almost half of the total energy use of commercial buildings. To optimize HVAC energy usage, it is important to understand the energy consumption of individual HVAC components at fine granularities. However, buildings typically only have aggregate building level power and thermal meters. We present HVACMeter, a system which leverages existing sensors in commercial HVAC systems to estimate the energy consumed by individual compone...

  8. From Statehouse to Schoolhouse: Education Finance Apportionment Systems in the United States

    Science.gov (United States)

    Verstegen, Deborah A.; Knoeppel, Robert C.

    2012-01-01

    This research investigates state finance policies for public elementary and secondary education using survey methodology. The purpose is to update the existing knowledge base in the field as well as to provide a compendium of finance and policy options that are being used across the states to finance school for lawmakers, educators and others.…

  9. Characterization and source apportionment of fine particulate sources at Rijeka, Croatia from 2013 to 2015

    Science.gov (United States)

    Ivošević, Tatjana; Stelcer, Eduard; Orlić, Ivica; Bogdanović Radović, Iva; Cohen, David

    2016-03-01

    PM2.5 daily aerosol samples were collected in Rijeka, Croatia during period from 6th August 2013 to 29th January 2015. In total, 259 samples were collected on Teflon filters and analyzed by PIXE and PIGE techniques to give information on 21 elements from Na to Pb. Additionally, black carbon was determined with the Laser Integrated Plate Method. Results were statistically evaluated using Positive Matrix Factorization (PMF). Eight major pollution sources: auto, smoke, secondary sulfates, heavy oil combustion, sea spray, road dust, industry iron and soil dust were identified together with their relative contributions in total PM2.5 pollution.

  10. Metals and metalloids in atmospheric dust: Use of lead isotopic analysis for source apportionment

    Science.gov (United States)

    Felix Villar, Omar I.

    Mining activities generate aerosol in a wide range of sizes. Smelting activities produce mainly fine particles ( 1 microm). The adverse effects of aerosols on human health depend mainly on two key characteristics: size and chemical composition. One of the main objectives of this research is to analyze the size distribution of contaminants in aerosol produced by mining operations. For this purpose, a Micro-Orifice Uniform Deposit Impactor (MOUDI) was utilized. Results from the MOUDI samples show higher concentrations of the toxic elements like lead and arsenic in the fine fraction (Mitigation strategies could be developed if the source of contamination is well defined. Environmental conditions as wind speed, wind direction, relative humidity and precipitation have an important role in the concentration of atmospheric dust. Dry environments with low relative humidity are ideal for the transport of aerosols. Results obtained from this research show the relationship between dust concentrations and meteorological parameters. Dust concentrations are highly correlated with relative humidity and wind speed. With all the data collected on site and the analysis of the meteorological parameters, models can be develop to predict the transport of particles as well as the concentration of contaminants at a specific point. These models were developed and are part of the results shown in this dissertation.

  11. Source apportionment of DDTs in maricultured fish: a modeling study in South China.

    Science.gov (United States)

    Fang, Shu-Ming; Bao, Lian-Jun; Yiruhan; Zeng, Eddy Y

    2016-04-01

    Fish is one of the most important nutrition sources for humanity. Contaminant exposure risk in fish farming will eventually deliver to the crowd through diet. China is the largest fish producing as well as exporting country, where mariculture plays an important role in fish production, especially in South China. Previous investigations indicated that a variety of compartments in farming areas of South China Sea were polluted by persistent organic pollutants, including DDT (dichlorodiphenyltrichloroethane) and its derivatives, some of which is designated as DDTs. In the present study, Hailing Bay and Daya Bay of Guangdong Province, China, were selected as the study sites and DDTs as the target compounds. A fish enrichment model was developed to assess the relative contributions of various pathways to the mass loadings of DDTs in the fish. Average concentrations (and concentration ranges) of DDTs in various environmental compartments of Hailing Bay and Daya Bay were included in modeling and analysis. Modeling results indicated that fish food and seawater contributed approximately the same proportions for the DDTs in maricultured fish. Antifouling paint was supposed to be the primary source of water DDTs in mariculture zone of Hailing Bay and Daya Bay, which contributed 69 % of the total DDTs to the mariculture water. We suggest that in order to protect people from consuming highly contaminated maricuture zone fish, the most effective and feasible methods are using environment-friendly antifouling paint and applying less polluted fish food in the fish reproduction process. PMID:26081772

  12. 33 CFR Appendix B to Part 277 - Hypothetical Example of Cost Apportionment

    Science.gov (United States)

    2010-07-01

    ...) $165,489 I b. Fixed charges (owner's share) 284,460 II A fixed charge such as engineering, design and... 440 440 0 1.0 440 Ties and Timber 20 67 6,000 4,000 10 .6213 2,485 Rail and Accessories: Rail, 110 lb... timber walkways 3,950 Total 18,360 Table IV—Expectable Savings in Repair or Maintenance Costs Repair...

  13. 26 CFR 1.861-9T - Allocation and apportionment of interest expense (temporary).

    Science.gov (United States)

    2010-04-01

    ... as to the source and use of funds. When borrowing will generally free other funds for other purposes... assets of the taxpayer and, thus, allocable to all the gross income which the assets of the taxpayer... borrowing and that substantially diminishes currency risk with respect to the borrowing or interest...

  14. Source apportionment and air quality impact assessment studies in Beijing/China

    Science.gov (United States)

    Suppan, P.; Schrader, S.; Shen, R.; Ling, H.; Schäfer, K.; Norra, S.; Vogel, B.; Wang, Y.

    2012-04-01

    More than 15 million people in the greater area of Beijing are still suffering from severe air pollution levels caused by sources within the city itself but also from external impacts like severe dust storms and long range advection from the southern and central part of China. Within this context particulate matter (PM) is the major air pollutant in the greater area of Beijing (Garland et al., 2009). PM did not serve only as lead substance for air quality levels and therefore for adverse health impact effects but also for a strong influence on the climate system by changing e.g. the radiative balance. Investigations on emission reductions during the Olympic Summer Games in 2008 have caused a strong reduction on coarser particles (PM10) but not on smaller particles (PM2.5). In order to discriminate the composition of the particulate matter levels, the different behavior of coarser and smaller particles investigations on source attribution, particle characteristics and external impacts on the PM levels of the city of Beijing by measurements and modeling are performed: Examples of long term measurements of PM2.5 filter sampling in 2005 with the objectives of detailed chemical (source attribution, carbon fraction, organic speciation and inorganic composition) and isotopic analyses as well as toxicological assessment in cooperation with several institutions (Karlsruhe Institute of Technology (IfGG/IMG), Helmholtz Zentrum München (HMGU), University Rostock (UR), Chinese University of Mining and Technology Beijing, CUMTB) will be discussed. Further experimental studies include the operation of remote sensing systems to determine continuously the MLH (by a ceilometer) and gaseous air pollutants near the ground (by DOAS systems) as well as at the 320 m measurement tower (adhesive plates at different heights for passive particle collection) in cooperation with the Institute of Atmospheric Physics (IAP) of the Chinese Academy of Sciences (CAS). The influence of the MLH on the air pollution concentration could be demonstrated and will be discussed. The impact of dust storm events on the overall pollution level of particulate matter in the greater area of Beijing is being assessed by the online coupled comprehensive model system COSMO-ART. First results of the dust storm modeling in northern China (2006, April 3rd until 12th) demonstrates very well the general behavior of the meteorological parameters temperature and humidity as well as a good agreement between modeled and measured dust storm concentration variability at Beijing in the course of time. The results show the importance of intertwine investigations of measurements and modeling, the analysis of local air pollution levels as well as the impact and analysis of advective process in the greater region of Beijing. Comprehensive investigations on particulate matter are a prerequisite for the knowledge of the source strengths and source attribution to the overall air pollution level. Only this knowledge can help to formulate and to introduce specific reduction measures to reduce coarser as well as finer particulates.

  15. Source apportionment advances using polar plots of bivariate correlation and regression statistics

    Science.gov (United States)

    Grange, Stuart K.; Lewis, Alastair C.; Carslaw, David C.

    2016-11-01

    This paper outlines the development of enhanced bivariate polar plots that allow the concentrations of two pollutants to be compared using pair-wise statistics for exploring the sources of atmospheric pollutants. The new method combines bivariate polar plots, which provide source characteristic information, with pair-wise statistics that provide information on how two pollutants are related to one another. The pair-wise statistics implemented include weighted Pearson correlation and slope from two linear regression methods. The development uses a Gaussian kernel to locally weight the statistical calculations on a wind speed-direction surface together with variable-scaling. Example applications of the enhanced polar plots are presented by using routine air quality data for two monitoring sites in London, United Kingdom for a single year (2013). The London examples demonstrate that the combination of bivariate polar plots, correlation, and regression techniques can offer considerable insight into air pollution source characteristics, which would be missed if only scatter plots and mean polar plots were used for analysis. Specifically, using correlation and slopes as pair-wise statistics, long-range transport processes were isolated and black carbon (BC) contributions to PM2.5 for a kerbside monitoring location were quantified. Wider applications and future advancements are also discussed.

  16. Source apportionment of particulate matter in Chinese megacities: the implication for emission control strategies

    Science.gov (United States)

    Huang, Ru-Jin; Elser, Miriam; Wang, Qiyuan Wang; Bozzetti, Carlo; Wolf, Robert; Wang, Yichen; Ni, Haiyan; Wang, Meng; Ho, Kin-Fai; Han, Yongming; Dällenbach, Kaspar; Canonaco, Francesco; Slowik, Jay; El Haddad, Imad; Baltensperger, Urs; Cao, Junji; Prévôt, André S. H.

    2015-04-01

    The rapid industrialization and urbanization in developing countries has led to an increase in air pollution, along a similar trajectory to that previously experienced by the developed nations. In China, particulate pollution is a serious environmental problem that is influencing air quality, regional and global climates, and human health. A quantitative understanding of these effects has proven extremely challenging due to spatial and temporal variability in the sources of aerosols and their precursors, the complexity of particle composition, and uncertainties associated with the atmospheric aging of existing particles (Pöschl 2005; Hallquist et al., 2009; Huang et al., 2014). Nowadays the average PM2.5 concentrations in China are approximately one to two orders of magnitude higher than those observed in urban areas in the US and European countries (Cao 2012). This has forced the Chinese government to announce its first national environmental standard for PM2.5 in 2012 and to make highly ambitious plans for emission control. The Chinese aim to reduce the PM2.5 concentrations by up to 25% of the 2012 levels by 2017, backed by 277 billion investments from the central government. To achieve this ambitious aim, a better understanding of the aerosol composition, sources, and atmospheric processing is required. In this study, we present the results from intensive field measurement campaigns carried out in Chinese megacities in 2013/2014. The sources of PM2.5 and the organic aerosol (OA) were investigated by applying the multi-linear engine (ME-2) receptor model (Canonaco et al., 2013) to a comprehensive dataset. Primary sources including vehicle emissions, biomass burning, coal burning, and dust-related emissions were identified and quantified. The contributions from secondary aerosol formation processes to total PM2.5 mass and OA mass were evaluated. Detailed results will be presented and discussed. References Cao, J. J. (2012) J. Earth Environ., 3, 1030-1036. Canonaco, F., Crippa, M., Slowik, J. G., Baltensperger, U., Prévôt, A. S. H. (2013) Atmos. Meas. Tech., 6, 3649-3661. Pöschl, U. (2005) Angew. Chem. Int. Ed., 44, 7520-7540. Hallquist, M., et al. (2009) Atmos. Chem. Phys., 9, 5155-5236. Huang, R.-J., et al. (2014) Nature 514, 218-222.

  17. Spatial distribution and source apportionment of PFASs in surface sediments from five lake regions, China

    Science.gov (United States)

    Qi, Yanjie; Huo, Shouliang; Xi, Beidou; Hu, Shibin; Zhang, Jingtian; He, Zhuoshi

    2016-01-01

    Perfluoroalkyl substances (PFASs) have been found in environment globally. However, studies on PFAS occurrence in sediments of lakes or reservoirs remain relatively scarce. In this study, two hundred and sixty-two surface sediment samples were collected from forty-eight lakes and two reservoirs all over China. Average PFAS concentrations in surface sediments from each lake or reservoir varied from 0.086 ng/g dw to 5.79 ng/g dw with an average of 1.15 ng/g dw. Among five lake regions, average PFAS concentrations for the lakes from Eastern Plain Region were the highest. Perfluorooctanoic acid, perfluoroundecanoic acid and perfluorooctane sulfonic acid (PFOS) were the predominant PFASs in surface sediments. The significant positive correlations between PFAS concentrations and total organic carbon, total nitrogen and total phosphorus contents in sediments revealed the influences of sedimentary characteristics on PFAS occurrence. A two-dimensional hierarchical cluster analysis heat map was depicted to analyze the possible origins of sediments and individual PFAS. The food-packaging, textile, electroplating, firefighting and semiconductor industry emission sources and the precious metals and coating industry emission sources were identified as the main sources by two receptor models, with contributions of 77.7 and 22.3% to the total concentrations of C4-C14- perfluoroalkyl carboxylic acids and PFOS, respectively. PMID:26947748

  18. Volatile aromatic compounds in Mexico City atmosphere: levels and source apportionment

    Energy Technology Data Exchange (ETDEWEB)

    Mugica, V. [Universidad Autonoma Metropolitana - Unidad Azcapotzalco, Mexico, D.F. (Mexico); Ruiz, M.E. [Instituto Mexicano del Petroleo, Mexico, D.F. (Mexico); Watson, J.; Chow, J. [Desert Research Institute, Reno, Nevada (United States)

    2003-01-01

    Samples of ambient air were simultaneously collected at three different sites of Mexico City in March of 1997 in order to quantify the most abundant volatile aromatic compounds and estimate the source contributions by application of the chemical mass balance model (CMB). Volatile aromatic compounds were around 20% of the total of non-methane hydrocarbons present in morning air samples. The most abundant volatile aromatic species in urban air were toluene and xylenes followed by 1, 2, 4 trimethylbenzene, benzene, ethylbenzene, metaethyltoluene, 1, 3, 5 trimethylbenzene, styrene, n propylbenzene, and isopropylbenzene. Sampling campaigns were carried out at crossroads, a bus station, a parking place, and areas where solvents and petroleum distillates are used, with the objective of determining people's exposure to volatile aromatic compounds. The CMB was applied for estimating the contribution of different sources to the presence of each one of the most abundant aromatic compounds. Motor vehicle exhaust was the main source of all aromatic compounds, especially gasoline exhaust, although diesel exhausts and asphalt operations also accounted for toluene, xylenes, ethylbenzene, propylbenzenes, and styrene. Graphic arts and paint applications had an important impact on the presence of toluene. [Spanish] Se colectaron simultaneamente muestras de aire ambiente en tres sitios de la Ciudad de Mexico durante el mes de marzo de 1997 con el fin de conocer las concentraciones y el origen de compuestos aromaticos utilizando el modelo de balance de masa de especies quimicas (CMB). Los compuestos aromaticos volatiles representaron alrededor del 20% del total de hidrocarburos no metalicos presentes en las muestras matutinas colectadas. Las especies aromaticas volatiles mas abundantes en el ambiente fueron el tolueno y los xilenos, seguidos por 1, 2, 4 trimetilbenceno, benceno, etilbenceno, metaetiltolueno, nporpilbenceno, isopropilbenceno, 1, 3, 5 trimetilbenceno y estireno. Se llevaron a cabo campanas de muestreo en cruceros, en una estacion de autobuses, un estacionamiento y algunos sitios en los que se utilizan disolventes y destilados de petroleo, para determinar los niveles de compuestos aromaticos volatiles a los que se expone la poblacion. Se aplico el modelo CMB para determinar la contribucion de distintas fuentes a la presencia en la atmosfera de cada uno de los compuestos aromaticos mas abundantes. El escape de vehiculos fue la fuente principal de todos los compuestos aromaticos, especialmente los de gasolina, aunque el escape de vehiculos a diesel y el asfaltado contribuyeron tambien en forma importante a la presencia de tolueno, xilenos, etilbenceno, propilbencenos y estireno. Las artes graficas y el uso de pinturas impactaron principalmente en la presencia de tolueno.

  19. Chemical characterization of fine organic aerosol for source apportionment at Monterrey, Mexico

    Directory of Open Access Journals (Sweden)

    Y. Mancilla

    2015-07-01

    Full Text Available Primary emissions from anthropogenic and biogenic sources as well as secondary formation are responsible for the pollution levels of ambient air in major urban areas. These sources release fine particles into the air that negatively impact human health and the environment. Organic molecular markers, which are compounds that are unique to specific PM2.5 sources, can be utilized to identify the major emission sources in urban areas. In this study, 43 representative PM2.5 samples, for both daytime and nighttime periods, were built from individual samples collected in an urban site of the Monterrey Metropolitan Area (MMA during the spring and fall of 2011 and 2012. The samples were analyzed for organic carbon, elemental carbon, and organic molecular markers. Several diagnostic tools were employed for the preliminary identification of emission sources. Organic compounds for eight compound classes were quantified. The n-alkanoic acids were the most abundant, followed by n-alkanes, wood smoke markers, and levoglucosan/alkenoic acids. Polycyclic aromatic hydrocarbons (PAHs and hopanes were less abundant. The carbon preference index (0.7–2.6 for n-alkanes indicate a major contribution of anthropogenic and mixed sources during the fall and the spring, respectively. Hopanes levels confirmed the contribution from gasoline and diesel engines. In addition, the contribution of gasoline and diesel vehicle exhaust was confirmed and identified by the PAH concentrations in PM2.5. Diagnostic ratios of PAH showed emissions from burning coal, wood, biomass, and other fossil fuels. The total PAH and elemental carbon (EC were correlated (r2 = 0.39–0.70 across the monitoring periods, reinforcing that motor vehicles are the major contributors of PAH. Cholesterol levels remained constant during the spring and fall, showing evidence of the contribution of meat cooking operations, while the isolated concentrations of levoglucosan suggested occasional biomass burning events. Finally, source attribution results obtained using the CMB model indicate that emissions from motor vehicle exhausts are the most important, accounting for the 64 % of the PM2.5. The vegetative detritus and biomass burning had the smallest contribution (2.2 % of the PM2.5. To our knowledge, this is the second study to explore the broad chemical characterization of fine organic aerosol in Mexico and the first for the MMA.

  20. Apportionment of sources affecting water quality: Case study of Kandla Creek, Gulf of Katchchh

    Digital Repository Service at National Institute of Oceanography (India)

    Dalal, S.G.; Shirodkar, P.V.; Verlekar, X.N.; Jagtap, T.G.; Rao, G.S.

    ://www.informaworld.com/terms-and-conditions-of-access.pdf This article may be used for research, teaching and private study purposes. Any substantial or systematic reproduction, re-distribution, re-selling, loan or sub-licensing, systematic supply or distribution in any form to anyone is expressly forbidden...

  1. Earth is (mostly) flat: apportionment of the flux of continental sediment over millennial time scales: COMMENT

    Science.gov (United States)

    Warrick, J.A.; Milliman, John D.; Walling, D.E.; Wasson, R.J.; Syvitski, J.P.M.; Aalto, R.E.

    2014-01-01

    Recent synthesis of 10Be-derived denudation rates by Willenbring et al. (2013) suggests that the “flat” areas of the world, those with average slopes of 2) using landscape slope as the controlling variable. We suggest that these findings are incorrect on several grounds.

  2. 26 CFR 1.861-9 - Allocation and apportionment of interest expense.

    Science.gov (United States)

    2010-04-01

    ... depreciation method, convention, and recovery period provided for under section 168(g) for the first taxable... the method, convention, and recovery period rules of the alternative depreciation system under section... determined by applying the method, convention, and recovery period rules of the alternative...

  3. Source apportionment of particulate matter in the US and associations with lung inflammatory markers

    Energy Technology Data Exchange (ETDEWEB)

    Duvall, R.M.; Norris, G.A.; Dailey, L.A.; Burke, J.M.; McGee, J.K.; Gilmour, M.I.; Gordon, T.; Devlin, R.B. [US EPA, Research Triangle Park, NC (United States). National Exposure Research Laboratory

    2008-07-01

    Size-fractionated particulate matter (PM) samples were collected from six U.S. cities and chemically analyzed as part of the Multiple Air Pollutant Study. Particles were administered to cultured lung cells and the production of three different proinflammatory markers was measured to explore the association between the health effect markers and PM. Ultrafine, fine, and coarse PM samples were collected between December 2003 and May 2004 over a 4-wk period in each city. Filters were pooled for each city and the PM samples were extracted then analyzed for trace metals, ions, and elemental carbon. Particle extracts were applied to cultured human primary airway epithelial cells, and the secreted levels of interleukin-8 (IL-8), heme oxygenase-1, and cyclooxygenase-2 were measured 1 and 24 h following exposure. Fine PM sources were quantified by the chemical mass balance (CMB) model. The relationship between toxicological measures, PM sources, and individual species were evaluated using linear regression. Ultrafine and fine PM mass were associated with increases in IL-8 (r{sup 2} = .80 for ultrafine and r{sup 2} = .52 for fine). Sources of fine PM and their relative contributions varied across the sampling sites and a strong linear association was observed between IL-8 and secondary sulfate from coal combustion (r{sup 2} = .79). Ultrafine vanadium, lead, copper, and sulfate were also associated with increases in IL-8. Increases in inflammatory markers were not observed for coarse PM mass and source markers. These findings suggest that certain PM size fractions and sources are associated with markers of lung injury or inflammation.

  4. Source apportionment of DDTs in maricultured fish: a modeling study in South China.

    Science.gov (United States)

    Fang, Shu-Ming; Bao, Lian-Jun; Yiruhan; Zeng, Eddy Y

    2016-04-01

    Fish is one of the most important nutrition sources for humanity. Contaminant exposure risk in fish farming will eventually deliver to the crowd through diet. China is the largest fish producing as well as exporting country, where mariculture plays an important role in fish production, especially in South China. Previous investigations indicated that a variety of compartments in farming areas of South China Sea were polluted by persistent organic pollutants, including DDT (dichlorodiphenyltrichloroethane) and its derivatives, some of which is designated as DDTs. In the present study, Hailing Bay and Daya Bay of Guangdong Province, China, were selected as the study sites and DDTs as the target compounds. A fish enrichment model was developed to assess the relative contributions of various pathways to the mass loadings of DDTs in the fish. Average concentrations (and concentration ranges) of DDTs in various environmental compartments of Hailing Bay and Daya Bay were included in modeling and analysis. Modeling results indicated that fish food and seawater contributed approximately the same proportions for the DDTs in maricultured fish. Antifouling paint was supposed to be the primary source of water DDTs in mariculture zone of Hailing Bay and Daya Bay, which contributed 69 % of the total DDTs to the mariculture water. We suggest that in order to protect people from consuming highly contaminated maricuture zone fish, the most effective and feasible methods are using environment-friendly antifouling paint and applying less polluted fish food in the fish reproduction process.

  5. Distribution and source apportionment studies of heavy metals in soil of cotton/wheat fields.

    Science.gov (United States)

    Rafique, Nazia; Tariq, Saadia R

    2016-05-01

    Heavy metals enriched agricultural soils have been the subject of great concern because these metals have potential to be transferred to the soil solution and afterward accumulated in food chain. To study the trace metal persistence in crop soil, 90 representative soil samples were collected and analyzed for heavy metal (As, Cd, Cu, Fe, Mn, Ni, Pb, and Zn) and anions (chloride, nitrates, phosphates and sulfates). Cluster and factor analysis techniques were used for the source identification of these excessive heavy metal levels and ecological risk was determined with potential ecological risk assessment. The degree of enrichment of eight studied heavy metals in comparison with the corresponding background levels decreased in order: Cd > Pb > Fe > Ni > Mn > As > Cu ~ Zn. Arsenic and cadmium exhibited 1.30- and 1.64-fold exceeded levels than threshold limits set by National environment quality standards, respectively. Cd in cotton field's soil may lead to higher potential risk than other heavy metals. On overall basis, the cumulative mean potential ecological risk for the district (207.75) corresponded to moderate risk level with higher contributions from As and Pb especially from Cd. Cadmium formed strong positive correlation with phosphate content of soil at p < 0.01. Cluster analysis indicated that Cluster 1 (extremely polluted) probably originated from anthropogenic inputs of phosphate fertilizer and past usage of arsenical pesticides.

  6. Polybrominated diphenyl ethers in farmland soils: source characterization, deposition contribution and apportionment.

    Science.gov (United States)

    Dong, Yian; Li, Li; Bie, Pengju; Jia, Shenglan; Wang, Qiang; Huang, Zhi; Qiu, Xinghua; Zhang, Jianbo; Hu, Jianxin

    2014-01-01

    Polybrominated diphenyl ethers (PBDEs), a group of persistent organic pollutants (POPs), are caused for concern recently due to their adverse health effects and environmental ubiquity. In this study, atmospheric and soil PBDE levels in Taizhou, one of the largest WEEE dismantling areas in the world, were measured, ranging from 884 to 2791 pg m(-3) with an average of 1968 pg m(-3) for atmosphere and 2.96 to 200 ng g(-1)dry weight (dw) with the mean of 65.2 ng g(-1)dw for farmland soils, respectively. The close connection between soil PBDE accumulation and atmospheric deposition was also revealed by the estimation of the annual PBDE deposition flux (3.1 ± 0.9 mg m(-2)a(-1)) and the similarity between deposited congener pattern and soil congener profile. Positive matrix factorization (PMF) was conducted to extract possible sources of farmland soil PBDEs and to calculate their contributions. Based on the measured source profiles of PBDE-related activities, five sources were identified representing WEEE dumping, WEEE dismantling, WEEE open burning, residential waste dismantling, and residential waste open burning. WEEE-related recycling activities contributed primary percentage (52%) to farmland soil PBDE concentration, and open burning was an important pathway for PBDEs entering the environment.

  7. Source identification and apportionment of heavy metals in urban soil profiles.

    Science.gov (United States)

    Luo, Xiao-San; Xue, Yan; Wang, Yan-Ling; Cang, Long; Xu, Bo; Ding, Jing

    2015-05-01

    Because heavy metals (HMs) occurring naturally in soils accumulate continuously due to human activities, identifying and apportioning their sources becomes a challenging task for pollution prevention in urban environments. Besides the enrichment factors (EFs) and principal component analysis (PCA) for source classification, the receptor model (Absolute Principal Component Scores-Multiple Linear Regression, APCS-MLR) and Pb isotopic mixing model were also developed to quantify the source contribution for typical HMs (Cd, Co, Cr, Cu, Mn, Ni, Pb, Zn) in urban park soils of Xiamen, a representative megacity in southeast China. Furthermore, distribution patterns of their concentrations and sources in 13 soil profiles (top 20 cm) were investigated by different depths (0-5, 5-10, 10-20 cm). Currently the principal anthropogenic source for HMs in urban soil of China is atmospheric deposition from coal combustion rather than vehicle exhaust. Specifically for Pb source by isotopic model ((206)Pb/(207)Pb and (208)Pb/(207)Pb), the average contributions were natural (49%)>coal combustion (45%)≫traffic emissions (6%). Although the urban surface soils are usually more contaminated owing to recent and current human sources, leaching effects and historic vehicle emissions can also make deep soil layer contaminated by HMs.

  8. Carbonaceous aerosols and pollutants over Delhi urban environment: Temporal evolution, source apportionment and radiative forcing

    International Nuclear Information System (INIS)

    Particulate matter (PM2.5) samples were collected over Delhi, India during January to December 2012 and analysed for carbonaceous aerosols and inorganic ions (SO42− and NO3−) in order to examine variations in atmospheric chemistry, combustion sources and influence of long-range transport. The PM2.5 samples are measured (offline) via medium volume air samplers and analysed gravimetrically for carbonaceous (organic carbon, OC; elemental carbon, EC) aerosols and inorganic ions (SO42− and NO3−). Furthermore, continuous (online) measurements of PM2.5 (via Beta-attenuation analyser), black carbon (BC) mass concentration (via Magee scientific Aethalometer) and carbon monoxide (via CO-analyser) are carried out. PM2.5 (online) range from 18.2 to 500.6 μg m−3 (annual mean of 124.6 ± 87.9 μg m−3) exhibiting higher night-time (129.4 μg m−3) than daytime (103.8 μg m−3) concentrations. The online concentrations are 38% and 28% lower than the offline during night and day, respectively. In general, larger night-time concentrations are found for the BC, OC, NO3−and SO42−, which are seasonally dependent with larger differences during late post-monsoon and winter. The high correlation (R2 = 0.74) between OC and EC along with the OC/EC of 7.09 (day time) and 4.55 (night-time), suggest significant influence of biomass-burning emissions (burning of wood and agricultural waste) as well as secondary organic aerosol formation during daytime. Concentrated weighted trajectory (CWT) analysis reveals that the potential sources for the carbonaceous aerosols and pollutants are local emissions within the urban environment and transported smoke from agricultural burning in northwest India during post-monsoon. BC radiative forcing estimates result in very high atmospheric heating rates (~ 1.8–2.0 K day−1) due to agricultural burning effects during the 2012 post-monsoon season. - Highlights: • Very high PM2.5 (> 200 µg m−3) levels over Delhi during agricultural burning period. • Enhanced levels of carbonaceous, sulphate and nitrate aerosol. • OC/EC suggests dominance of biomass burning and SOA formation. • BC highly contributes (50~70%) to the aerosol radiative forcing

  9. Measurement of Greenhouse gases (GHGs) and source apportionment in Bakersfield, CA during CalNex 2010

    Science.gov (United States)

    Guha, A.; Gentner, D. R.; Weber, R.; Gardner, A.; Provencal, R. A.; Goldstein, A. H.

    2011-12-01

    The California Global Warming Solutions Act 2006 (AB 32) creates a need to verify and validate the state GHG inventory, which is largely based on activity data and emission factor based estimates. The "bottom-up" emission factors for methane (CH4) and nitrous oxide (N2O) have large uncertainties and there is a lack of adequate "top-down" measurements to characterize emission rates from sources. Emissions from non-CO2 GHG sources display spatial heterogeneity and temporal variability, and are thus, often, poorly characterized. The Central Valley of California is an agriculture and industry intensive region with huge concentration of dairies, refineries and active oil fields which are known CH4 sources. As part of the CalNex campaign, we performed measurements of principal trace GHG gases (CO2, CH4, and N2O) and combustion tracer CO at the Bakersfield super-site during the summer of 2010. Measurements were made over a period of six weeks using fast response lasers based on cavity enhanced absorption spectroscopy (LGR Inc. CA). Coincident measurements of hundreds of volatile organic compounds (VOCs) served as anthropogenic and biogenic tracers of the GHG sources at local and regional levels. The local mean CH4 (1.93ppm) and N2O (325ppb) minimum are larger than that measured at Mauna Loa (NOAA). Daytime winds from the north-west draw emissions from the city center, Fruitvale oilfield and two refineries. Huge enhancements of CH4 relative to CO2 (> 4ppm of CH4) are seen on some days but almost on each night, when wind reversal and valley backflow brings winds from the east (oil fields and landfill). Winds from south-southwest (dairies) have ΔCH4 / ΔCO2 ratios similar to previous dairy chamber studies (Mitloehner et al., 2009). The ΔCH4 / ΔCO ratios at Bakersfield are much larger than that calculated downwind of Los Angeles at Mt. Wilson (Hsu et al., 2009) or in-flight measurements during CalNex (NOAA) suggesting additional non-combustion sources strongly influence the ambient levels of CH4 locally. ΔCH4 / ΔCO2 ratios during peak traffic hours are 40 to 50 times higher than FTP vehicle dynamometer tests confirming the presence and dominance of non-vehicular CH4 emissions sources. ΔN2O /ΔCO2 ratios during morning commute hours ( NW winds) are similar to fleet emissions ratios from literature. CH4 correlates moderately with C3-C6 straight chain alkanes (also found in raw natural gas). The correlation slopes are similar to those measured downwind from Wattenberg oil field in Colorado and obtained natural gas samples (Petron et al., 2010) suggesting fugitive emissions is a likely source. CH4 or the C3-C6 alkanes do not correlate with any of the gasoline or diesel fuel specific tracers (isooctane and toluene) confirming vehicular combustion is not a major source of CH4. Partial analysis of ethanethiol (CH3-CH2-SH) which is a natural gas odorant indicates strong correlation with CH4. CH4 correlates fairly well with acetone that is also emitted from dairies. Further analysis of VOC measurements and meteorological data will lead to better source attribution and emission factors that will be compared to previously reported data from ground measurements and inventory calculations.

  10. Source Apportionment of Stack Emissions from Research and Development Facilities Using Positive Matrix Factorization

    Energy Technology Data Exchange (ETDEWEB)

    Ballinger, Marcel Y. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Larson, Timothy V. [Univ. of Washington, Seattle, WA (United States)

    2014-08-19

    Emissions from research and development (R&D) facilities are difficult to characterize due to the wide variety of processes used, changing nature of research, and large number of chemicals. Positive matrix factorization (PMF) was applied to volatile organic compounds (VOCs) concentrations measured in the main exhaust stacks of four different R&D buildings to identify the number and composition of major contributing sources. PMF identified from 9-11 source-related factors contributing to the stack emissions depending on the building. The factors that were similar between buildings were major contributors to trichloroethylene (TCE), acetone, and ethanol emissions. Several other factors had similar profiles for two or more buildings but not for all four. One factor for each building was a combination of p/m-xylene, o-xylene and ethylbenzene. At least one factor for each building was identified that contained a broad mix of many species and constraints were used in PMF to modify the factors to resemble more closely the off-shift concentration profiles. PMF accepted the constraints with little decrease in model fit. Although the PMF model predicted the profiles of the off-shift samples, the percent of total emissions was under-predicted by the model versus the measured data.

  11. PM2.5 pollution in a megacity of southwest China: source apportionment and implication

    Science.gov (United States)

    Tao, J.; Gao, J.; Zhang, L.; Zhang, R.; Che, H.; Zhang, Z.; Lin, Z.; Jing, J.; Cao, J.; Hsu, S.-C.

    2014-08-01

    Daily PM2.5 (aerosol particles with an aerodynamic diameter of less than 2.5 μm) samples were collected at an urban site in Chengdu, an inland megacity in southwest China, during four 1-month periods in 2011, with each period in a different season. Samples were subject to chemical analysis for various chemical components ranging from major water-soluble ions, organic carbon (OC), element carbon (EC), trace elements to biomass burning tracers, anhydrosugar levoglucosan (LG), and mannosan (MN). Two models, the ISORROPIA II thermodynamic equilibrium model and the positive matrix factorization (PMF) model, were applied to explore the likely chemical forms of ionic constituents and to apportion sources for PM2.5. Distinctive seasonal patterns of PM2.5 and associated main chemical components were identified and could be explained by varying emission sources and meteorological conditions. PM2.5 showed a typical seasonality of waxing in winter and waning in summer, with an annual mean of 119 μg m-3. Mineral soil concentrations increased in spring, whereas biomass burning species elevated in autumn and winter. Six major source factors were identified to have contributed to PM2.5 using the PMF model. These were secondary inorganic aerosols, coal combustion, biomass burning, iron and steel manufacturing, Mo-related industries, and soil dust, and they contributed 37 ± 18, 20 ± 12, 11 ± 10, 11 ± 9, 11 ± 9, and 10 ± 12%, respectively, to PM2.5 masses on annual average, while exhibiting large seasonal variability. On annual average, the unknown emission sources that were not identified by the PMF model contributed 1 ± 11% to the measured PM2.5 mass. Various chemical tracers were used for validating PMF performance. Antimony (Sb) was suggested to be a suitable tracer of coal combustion in Chengdu. Results of LG and MN helped constrain the biomass burning sources, with wood burning dominating in winter and agricultural waste burning dominating in autumn. Excessive Fe (Ex-Fe), defined as the excessive portion in measured Fe that cannot be sustained by mineral dust, is corroborated to be a straightforward useful tracer of iron and steel manufacturing pollution. In Chengdu, Mo / Ni mass ratios were persistently higher than unity, and considerably distinct from those usually observed in ambient airs. V / Ni ratios averaged only 0.7. Results revealed that heavy oil fuel combustion should not be a vital anthropogenic source, and additional anthropogenic sources for Mo are yet to be identified. Overall, the emission sources identified in Chengdu could be dominated by local sources located in the vicinity of Sichuan, a result different from those found in Beijing and Shanghai, wherein cross-boundary transport is significant in contributing pronounced PM2.5. These results provided implications for PM2.5 control strategies.

  12. Spatio-Temporal Variations and Source Apportionment of Water Pollution in Danjiangkou Reservoir Basin, Central China

    Directory of Open Access Journals (Sweden)

    Pan Chen

    2015-05-01

    Full Text Available Understanding the spatio-temporal variation and the potential source of water pollution could greatly improve our knowledge of human impacts on the environment. In this work, data of 11 water quality indices were collected during 2012–2014 at 10 monitoring sites in the mainstream and major tributaries of the Danjiangkou Reservoir Basin, Central China. The fuzzy comprehensive assessment (FCA, the cluster analysis (CA and the discriminant analysis (DA were used to assess the water pollution status and analyze its spatio-temporal variation. Ten sites were classified by the high pollution (HP region and the low pollution (LP region, while 12 months were divided into the wet season and the dry season. It was found that the HP region was mainly in the small tributaries with small drainage areas and low average annual discharges, and it was also found that most of these rivers went through urban areas with industrial and domestic sewages input into the water body. Principal component analysis/factor analysis (PCA/FA was applied to reveal potential pollution sources, whereas absolute principal component score-multiple linear regression (APCS-MLR was used to identify their contributions to each water quality variable. The study area was found as being generally affected by industrial and domestic sewage. Furthermore, the HP region was polluted by chemical industries, and the LP region was influenced by agricultural and livestock sewage.

  13. 77 FR 27277 - FTA Supplemental Fiscal Year 2012 Apportionments, Allocations, and Program Information

    Science.gov (United States)

    2012-05-09

    ... Administration (FTA) annually publishes one or more notices apportioning funds appropriated by law. In some cases... (FY) 2012 contract authority because the current authorization of FTA's programs provides contract... current programs. The Surface Transportation Extension Act of 2012, Public Law 112-102, continues...

  14. Characteristics, toxicity, and source apportionment of polycylic aromatic hydrocarbons (PAHs) in road dust of Ulsan, Korea

    Energy Technology Data Exchange (ETDEWEB)

    Dong, T.T.T.; Lee, B.K. [University of Ulsan, Ulsan (Republic of Korea). Dept. of Civil & Environmental Engineering

    2009-03-15

    This study identified concentrations, molecular distributions, toxicities, and sources of polycyclic aromatic hydrocarbons (PAHs) in road dust from different areas of Ulsan, the largest industrial city in Korea. The total PAH concentrations in industrial areas were dependent on industrial emissions and vehicular exhaust, while those in urban areas were mainly dependent on traffic density, sampling site location, and accumulation of pollutants or road dust. The PAH concentration of each particle size group increased with decreasing particle size. This may be because of the higher surface area available for deposition or coating of PAHs in road dust with smaller particle sizes. The molecular distributions of PAHs among the sites in the petrochemical area and heavy traffic area were similar because of the similarities in their emission sources. The toxic equivalent concentrations (TEQs) of PAHs in the road dust ranged from 0.93 {mu}g/g to 16.74 {mu}g/g in industrial areas and from 4.37 {mu}g/g to 68.84 {mu}g/g in urban areas. The correlation coefficient of total PAH concentration and TEQ in urban areas was 0.98, which was much higher than that in industrial areas where it was 0.75. Principal component analysis showed that PAHs in road dust from Ulsan originate from four main sources: diesel vehicular emissions, oil combustion, gasoline vehicular emissions, and coal combustion.

  15. Characteristics, toxicity, and source apportionment of polycylic aromatic hydrocarbons (PAHs) in road dust of Ulsan, Korea.

    Science.gov (United States)

    Dong, Trang T T; Lee, Byeong-Kyu

    2009-03-01

    This study identified concentrations, molecular distributions, toxicities, and sources of polycylic aromatic hydrocarbons (PAHs) in road dust from different areas of Ulsan, the largest industrial city in Korea. The total PAH concentrations in industrial areas were dependent on industrial emissions and vehicular exhaust, while those in urban areas were mainly dependent on traffic density, sampling site location, and accumulation of pollutants or road dust. The PAH concentration of each particle size group increased with decreasing particle size. This may be because of the higher surface area available for deposition or coating of PAHs in road dust with smaller particle sizes. The molecular distributions of PAHs among the sites in the petrochemical area and heavy traffic area were similar because of the similarities in their emission sources. The toxic equivalent concentrations (TEQs) of PAHs in the road dust ranged from 0.93 microg/g to 16.74 microg/g in industrial areas and from 4.37 microg/g to 68.84 microg/g in urban areas. The correlation coefficient of total PAH concentration and TEQ in urban areas was 0.98, which was much higher than that in industrial areas where it was 0.75. Principal component analysis showed that PAHs in road dust from Ulsan originate from four main sources: diesel vehicular emissions, oil combustion, gasoline vehicular emissions, and coal combustion. PMID:19103459

  16. Characteristics and source apportionment of PM1 emissions at a roadside station

    International Nuclear Information System (INIS)

    Highlights: → We present results from 24 h roadside measurements of PM1 mass and main components. → Elemental carbon, organic matter, and sulfate are the dominant components. → All elements related to human health are lower than the guideline values. → Vehicle exhaust episodes occur during summer. → Secondary aerosols and incinerator/biomass burning episodes exist during winter. - Abstract: The mass concentrations of PM1 (particles less than 1.0 μm in aerodynamic diameter), organic carbon (OC), elemental carbon (EC), water-soluble ions, and up to 25 elements were reported for 24 h aerosol samples collected every sixth day at a roadside sampling station in Hong Kong from October 2004 to September 2005. Annual average PM1 mass concentration was 44.5 ± 19.5 μg m-3. EC, OM (organic matter, OC x 1.2), and SO4= were the dominant components, accounting for ∼36%, ∼26%, and ∼24% of PM1, respectively. Other components, i.e., NO3-, NH4+, geological material, trace elements and unidentified material, comprised the remaining ∼14%. Annual average OC/EC ratio (0.6 ± 0.3) was low, indicating that primary vehicle exhaust was the major source of carbonaceous aerosols. The seasonal variations of pollutants were due to gas-particle partitioning processes or a change in air mass rather than secondary aerosol produced locally. Vehicle exhaust, secondary aerosols, and waste incinerator/biomass burning were dominant air pollution sources, accounting for ∼38%, ∼22% and ∼16% of PM1, respectively. Pollution episodes during summer (May-August) which were frequently accompanied by tropical storms or typhoons were dominated by vehicle emissions. During winter (November-February) pollution episodes coincided with northeasterly monsoons were characterized by secondary aerosols and incinerator/biomass burning emissions.

  17. Characterization and source apportionment of particle number concentration at a semi-urban tropical environment.

    Science.gov (United States)

    Khan, Md Firoz; Latif, Mohd Talib; Amil, Norhaniza; Juneng, Liew; Mohamad, Noorlin; Nadzir, Mohd Shahrul Mohd; Hoque, Hossain Mohammed Syedul

    2015-09-01

    Principal component analysis (PCA) and correlation have been used to study the variability of particle mass and particle number concentrations (PNC) in a tropical semi-urban environment. PNC and mass concentration (diameter in the range of 0.25->32.0 μm) have been measured from 1 February to 26 February 2013 using an in situ Grimm aerosol sampler. We found that the 24-h average total suspended particulates (TSP), particulate matter ≤10 μm (PM10), particulate matter ≤2.5 μm (PM2.5) and particulate matter ≤1 μm (PM1) were 14.37 ± 4.43, 14.11 ± 4.39, 12.53 ± 4.13 and 10.53 ± 3.98 μg m(-3), respectively. PNC in the accumulation mode (spectroradiometer (MODIS) distribution. PMID:25925145

  18. Source apportionment of PM10 at a small industrial area using Positive Matrix Factorization

    Science.gov (United States)

    Lim, Jong-Myoung; Lee, Jin-Hong; Moon, Jong-Hwa; Chung, Yong-Sam; Kim, Ki-Hyun

    2010-01-01

    In this study, PM10-bound concentrations of 28 trace metals and 3 ionic components were measured from samples collected at Daejeon Industrial Complexes I and II, Korea from April 2000 to December 2002. Positive matrix factorization (PMF) and conditional probability function (CPF) were applied to these PM data sets to identify the diverse sources in the industrial area. A total of nine source types were identified to be important which include: secondary aerosol, cement/construction, soil dust, road dust, vehicle exhaust, incineration/Pb-related industry, metal smelting, fossil fuel combustion, and field burning. Results of our study suggest that there are competing relationships between anthropogenic and natural source processes in this industrial area.

  19. Source apportionment of PM 10 at residential and industrial sites of an urban region of Kolkata, India

    Science.gov (United States)

    Karar, Kakoli; Gupta, A. K.

    2007-03-01

    PM 10 and its chemical species mass concentrations were measured once in a week at residential (Kasba) and industrial (Cossipore) sites of an urban region of Kolkata for a period of 24 h during November 2003 to November 2004. At each monitoring site, 53 sets of daily average PM 10 samples were collected during the study period. Approximately 55% of the monitoring days are weekdays, while 45% are weekends. The PM 10 mass concentrations ranged from 68.2 to 280.6 μg m - 3 at the residential site, and 62.4 to 401.2 μg m - 3 at the industrial site. Polycyclic aromatic hydrocarbon compounds (PAH), fluoranthene (Fl), pyrene (Py), benzo(a)anthracene (BaA), benzo(b)fluoranthene (BbF) and benzo(a)pyrene (BaP) have been analyzed using Gas Chromatoghaphy. Metals in PM 10 deposited on quartz microfibre filter papers were measured using an Inductively Coupled Plasma-Atomic Emission Spectrometer. Chromium (Cr), zinc (Zn), lead (Pb), cadmium (Cd), nickel (Ni), manganese (Mn) and iron (Fe) are the seven toxic trace metals quantified from the measured PM 10 concentrations. Total carbon (TC), inorganic carbon (IC) and organic carbon (OC) were analyzed using a Carbon analyzer. Exposed quartz microfibre filter papers were also analyzed for water-soluble anions of fluoride (F -), chloride (Cl -), nitrate (NO 3-), phosphate (PO 43-) and sulfate (SO 42-) using ion chromatography. In this study, principal component analysis (PCA)/absolute principal component scores (APCS) model was applied to the mass concentrations of PM 10 and its chemical species. Principal component analysis with varimax rotation identified five possible sources; solid waste dumping, vehicular emission, coal combustion, cooking and soil dust at residential site. The extracted possible sources at the industrial site were vehicular emissions, coal combustion, electroplating industry, tyre wear and secondary aerosol. A quantitative estimation by principal component analysis-multiple linear regression (PCA-MLR) model indicated that solid waste dumping contributed 36%, vehicular emissions 26%, coal combustion 13%, cooking 8% and soil dust 4% at the residential site. The PCA-MLR apportioned 37% to vehicular emissions, 29% to coal combustion, 18% to electroplating industry, 8% to tyre wear and 1% to secondary aerosol at the industrial site. Due to the limitation in source marker species analyzed, 13% at Kasba and 7% at Cossipore could not be apportioned to any possible sources by this technique.

  20. Brown carbon and thermal-optical analysis: A correction based on optical multi-wavelength apportionment of atmospheric aerosols

    Science.gov (United States)

    Massabò, D.; Caponi, L.; Bove, M. C.; Prati, P.

    2016-01-01

    Thermo-optical analysis is widely adopted for the quantitative determination of total, TC, organic, OC and elemental, EC, Carbon in aerosol samples collected on quartz fibre filters. Nevertheless, the methodology presents several issues in particular about the artefacts related to the formation of pyrolytic carbon. It is usually neglected the uncertainty due to the possible presence of brown carbon (BrC) in the sample under analysis, i.e. the optically active fraction of OC produced by biomass burning and with characteristics intermediate between OC and EC. We introduce here a novel correction to the standard thermo-optical protocol based on the determination of the fraction of the sample absorbance due to the (possible) presence of BrC. This is achievable thanks to the coupled use of the Multi Wavelength Absorbance Analyser (MWAA) of the University of Genoa and a standard Sunset Inc. EC/OC analyser. Our correction provides a firmer OC/EC separation as well as an operative quantification of the BrC mass. The methodology has been validated against independent determination of the levoglucosan content in the same filters sent to the Sunset analysis. Corrections up to 23% in the OC and EC values, determined via the standard and new thermo-optical analysis, have been found in a set of PM10 (i.e. Particulate Matter with aerodynamic diameter less than 10 μm) samples collected wintertime at a mountain site in Northern Italy.

  1. Temporal variations and source apportionment of Hulis-C in PM2.5 in urban Shanghai.

    Science.gov (United States)

    Zhao, Mengfei; Qiao, Ting; Li, Yulan; Tang, Xiaoxing; Xiu, Guangli; Yu, Jian Zhen

    2016-11-15

    Humic-like substances (Hulis), the hydrophobic part of water-soluble organic compounds, have been recognized to play important roles in environmental behavior of PM2.5 in atmosphere. In this study, Hulis and other components of PM2.5, collected in urban Shanghai from September 2013 to August 2014 were analyzed. The annual average concentration of Hulis carbon (Hulis-C) was (2.61±2.58) μg/m(3), accounting for about 50% of water-soluble organic carbon (WSOC). The monthly average Hulis-C concentration peaked in December while the lowest was in summer, coinciding with the high and low of levoglucosan and secondary inorganic aerosol (SIA). Biomass burning and secondary formation were both important sources of Hulis-C, and their contributions showed obvious seasonality. In late autumn and winter, the strong inter-correlations among Hulis-C concentrations, NO3(-)/SO4(2-) mass ratios and nitrogen oxidation ratios (NOR) were found, suggesting the atmospheric oxidation of NOx to nitrate and related gas-phase reactions may be inter-linked with Hulis-C formation. In summer, photochemical reaction was clearly the major source of Hulis-C. The investigation by backward trajectory analysis showed that the long-range transport from the Northwest brought large amounts of PM2.5 and enhanced Hulis-C and levoglucosan level, indicating biomass burning as a significant source of Hulis-C under this type of synoptic weather conditions. In comparison, Hulis formation associated with the NOx oxidation pathway was mainly associated with the short-range transport from the neighboring cities. Marine aerosol was relatively clean and had little effects on Hulis-C. The CWT (concentration weighted trajectory) model results suggested that the Yangtze River Delta (YRD) region was an important source region of Hulis-C, while the effect of some northwestern areas was not negligible. PMID:27454571

  2. Spatial Distribution, Air-Water Fugacity Ratios and Source Apportionment of Polychlorinated Biphenyls in the Lower Great Lakes Basin.

    Science.gov (United States)

    Khairy, Mohammed; Muir, Derek; Teixeira, Camilla; Lohmann, Rainer

    2015-12-01

    Polychlorinated biphenyls (PCBs) continue to be contaminants of concern across the Great Lakes. It is unclear whether current concentrations are driven by ongoing primary emissions from their original uses, or whether ambient PCBs are dominated by their environmental cycling. Freely dissolved PCBs in air and water were measured using polyethylene passive samplers across Lakes Erie and Ontario during summer and fall, 2011, to investigate their spatial distribution, determine and apportion their sources and to asses their air-water exchange gradients. Average gaseous and freely dissolved ∑29 PCB concentrations ranged from 5.0 to 160 pg/m(3) and 2.0 to 55 pg/L respectively. Gaseous concentrations were significantly correlated (R(2) = 0.80) with the urban area within a 3-20 km radius. Fugacity ratios indicated that the majority of PCBs are volatilizing from the water thus acting as a secondary source for the atmosphere. Dissolved PCBs were probably linked to PCB emissions from contaminated sites and areas of concern. Positive matrix factorization indicated that although volatilized Aroclors (gaseous PCBs) and unaltered Aroclors (dissolved PCBs) dominate in some samples, ongoing non-Aroclor sources such as paints/pigments (PCB 11) and coal/wood combustion showed significant contributions across the lower Great Lakes. Accordingly, control strategies should give further attention to PCBs emitted from current use sources.

  3. Source apportionment of sulfate and nitrate particulate matter in the Eastern United States and effectiveness of emission control programs.

    Science.gov (United States)

    Zhang, Hongliang; Hu, Jianlin; Kleeman, Michael; Ying, Qi

    2014-08-15

    Reducing population exposure to PM2.5 in the eastern US will require control of secondary sulfate and nitrate. A source-oriented Community Multi-scale Air Quality (CMAQ) model is used to determine contributions of major emission sources to nitrate and sulfate concentrations in the seven eastern US cities (New York City, Pittsburgh, Baltimore, Chicago, Detroit, St. Paul, and Winston-Salem) in January and August of 2000 and 2006. Identified major nitrate sources include on-road gasoline-powered vehicles, diesel engines, natural gas and coal combustion. From 2000 to 2006, January nitrate concentrations decreased by 25-68% for all the seven cities. On average, ~53% of this change was caused by emissions controls while 47% was caused by meteorology variations. August nitrate concentrations decreased by a maximum of 68% in New York City but Detroit experienced increasing August nitrate concentrations by up to 33%. On average, ~33% of the reduction in nitrate is offset by increases associated with meteorological conditions that favor nitrate formation. Coal combustion and natural gas are the dominant sources for sulfate in both seasons. January sulfate decrease from 2000 to 2006 in all cities by 4-58% except New York City, which increases by 13%. On average, ~93% of the reduction in sulfate was attributed to emission controls with 7% associated with changes in meteorology. August sulfate concentrations decrease by 11-44% in all cities. On average, emission controls alone between 2000 and 2006 would have caused 6% more reduction but the effectiveness of the controls was mitigated by meteorology conditions more favorable to sulfate production in 2006 vs. 2000. The results of this study suggest that regional emissions controls between 2000 and 2006 have been effective at reducing population exposure to PM2.5 in the eastern US, but yearly variations in meteorology must be carefully considered when assessing the exact magnitude of the control benefits.

  4. The effect of federal fuel sulfur regulations on in-use fleets: on-road heavy-duty source apportionment.

    Science.gov (United States)

    Johnson, Jason P; Kittelson, David B; Watts, Winthrop F

    2009-07-15

    From 2002 to 2007 fuel sulfur content in the Minneapolis/St Paul area decreased from about 325 ppm S to vehicles were measured to be 9.1 +/- 6.6 x 10(15) and 3.2 +/- 2.8 x 10(15) particles/kg of fuel burned, in 2006 and 2007, respectively, a reduction of 65%. In an earlier study in 2002 particle number emissions for the in-use HD fleet were 4.2 +/- 0.6 x 10(15) particles/km compared to the current measurements of 2.8 +/- 2.1 x 10(15) and 9.9 +/- 8.7 x 10(14) particles/km in 2006 and 2007, respectively. The HD particle mass emission standard remained unchanged from 1994 through 2006 and few 2007 HD vehicles were on the road at the time of this study so the decreases in number observed emissions are more likely due to reductions in the sulfur content of the fuel than to changes in engine and aftertreatment design.

  5. Aerosol composition and source apportionment in the Mexico City Metropolitan Area with PIXE/PESA/STIM and multivariate analysis

    Directory of Open Access Journals (Sweden)

    K. S. Johnson

    2006-01-01

    Full Text Available Aerosols play an important role in the atmosphere but are poorly characterized, particularly in urban areas like the Mexico City Metropolitan Area (MCMA. The chemical composition of urban particles must be known to assess their effects on the environment, and specific particulate emissions sources should be identified to establish effective pollution control standards. For these reasons, samples of particulate matter ≤2.5 μm (PM2.5 were collected during the MCMA-2003 Field Campaign for elemental and multivariate analyses. Proton-Induced X-ray Emission (PIXE, Proton-Elastic Scattering Analysis (PESA and Scanning Transmission Ion Microscopy (STIM measurements were done to determine concentrations of 19 elements from Na to Pb, hydrogen, and total mass, respectively. The most abundant elements from PIXE analysis were S, Si, K, Fe, Ca, and Al, while the major emissions sources associated with these elements were industry, wind-blown soil, and biomass burning. Wind trajectories suggest that metals associated with industrial emissions came from northern areas of the city whereas soil aerosols came from the southwest and increased in concentration during dry conditions. Elemental markers for fuel oil combustion, V and Ni, correlated with a large SO2 plume to suggest an anthropogenic, rather than volcanic, emissions source. By subtracting major components of soil and sulfates determined by PIXE analysis from STIM total mass measurements, we estimate that approximately 50% of non-volatile PM2.5 consisted of carbonaceous material.

  6. Aerosol composition and source apportionment in the Mexico City Metropolitan Area with PIXE/PESA/STIM and multivariate analysis

    Directory of Open Access Journals (Sweden)

    K. S. Johnson

    2006-05-01

    Full Text Available Aerosols play an important role in the atmosphere but are poorly characterized, particularly in urban areas like the Mexico City Metropolitan Area (MCMA. The chemical composition of urban particles must be known to assess their effects on the environment, and specific particulate emissions sources should be identified to establish effective pollution control standards. For these reasons, samples of particulate matter ≤2.5 μm (PM2.5 were collected during the MCMA-2003 Field Campaign for elemental and multivariate analyses. Proton-Induced X-ray Emission (PIXE, Proton-Elastic Scattering Analysis (PESA and Scanning Transmission Ion Microscopy (STIM techniques were done to determine concentrations of 19 elements from Na to Pb, hydrogen, and total mass, respectively. The most abundant elements from PIXE analysis were S, Si, K, Fe, Ca, and Al, while the major emissions sources associated with these elements were industry, wind-blown soil, and biomass burning. Wind trajectories suggest that metals associated with industrial emissions came from northern areas of the city whereas soil aerosols came from the southwest and increased in concentration during dry conditions. Elemental markers for fuel oil combustion V and Ni correlated with a large SO2 plume to suggest an anthropogenic, rather than volcanic, emissions source. By subtracting major components of soil and sulfate determined by PIXE analysis from STIM total mass measurements, we estimate that approximately 50% of non-volatile PM2.5 consisted of carbonaceous material.

  7. Source apportionment of PM₁₀ and PM₂.₅ in a desert region in northern Chile.

    Science.gov (United States)

    Jorquera, Héctor; Barraza, Francisco

    2013-02-01

    Estimating contributions of anthropogenic sources to ambient particulate matter (PM) in desert regions is a challenging issue because wind erosion contributions are ubiquitous, significant and difficult to quantify by using source-oriented, dispersion models. A receptor modeling analysis has been applied to ambient PM(10) and PM(2.5) measured in an industrial zone ~20 km SE of Antofagasta (23.63°S, 70.39°W), a midsize coastal city in northern Chile; the monitoring site is within a desert region that extends from northern Chile to southern Perú. Integrated 24-hour ambient samples of PM(10) and PM(2.5) were taken with Harvard Impactors; samples were analyzed by X Ray Fluorescence, ionic chromatography (NO(3)(-) and SO(4)(=)), atomic absorption (Na(+), K(+)) and thermal optical transmission for elemental and organic carbon determination. Receptor modeling was carried out using Positive Matrix Factorization (US EPA Version 3.0); sources were identified by looking at specific tracers, tracer ratios, local winds and wind trajectories computed from NOAA's HYSPLIT model. For the PM(2.5) fraction, six contributions were found - cement plant, 33.7 ± 1.3%; soil dust, 22.4 ± 1.6%; sulfates, 17.8 ± 1.7%; mineral stockpiles and brine plant, 12.4 ± 1.2%; Antofagasta, 8.5 ± 1.3% and copper smelter, 5.3 ± 0.8%. For the PM(10) fraction five sources were identified - cement plant, 38.2 ± 1.5%; soil dust, 31.2 ± 2.3%; mineral stockpiles and brine plant, 12.7 ± 1.7%; copper smelter, 11.5 ± 1.6% and marine aerosol, 6.5 ± 2.4%. Therefore local sources contribute to ambient PM concentrations more than distant sources (Antofagasta, marine aerosol) do. Soil dust is enriched with deposition of marine aerosol and calcium, sulfates and heavy metals from surrounding industrial activities. The mean contribution of suspended soil dust to PM(10) is 50 μg/m(3) and the peak daily value is 104 μg/m(3). For the PM(2.5) fraction, suspended soil dust contributes with an average of 9.3 μg/m(3) and a peak daily value of 31.5 μg/m(3). PMID:23280290

  8. Source apportionment with uncertainty estimates of fine particulate matter in Ostrava, Czech Republic using Positive Matrix Factorization

    Science.gov (United States)

    A 14-week investigation during a warm and cold seasons was conducted to improve understanding of air pollution sources that might be impacting air quality in Ostrava, the Czech Republic. Fine particulate matter (PM2.5) samples were collected in consecutive 12-h day and night incr...

  9. Advanced source apportionment of PM2.5 using online mass spectrometry in two major cities in China

    Science.gov (United States)

    Prevot, Andre S. H.; Elser, Miram; Huang, Rujin; Slowik, Jay; Wang, Qiyuan; Canonaco, Francesco; Bozzetti, Carlo; Cao, Junji; Baltensperger, Urs; El Haddad, Imad

    2016-04-01

    During winter 2013-2014 aerosol mass spectrometer (AMS) measurements were conducted in two major cities of China: Xi'an and Beijing. The AMS was equipped with a recently developed aerodynamic lens for direct measurements of the PM2.5 fraction for the first time in Asia (Williams et al., 2013). We could show that around 40% of the mass is lost using a conventional PM1 inlet. The statistical tool multi-linear engine 2 using constrained positive matrix factorization was used to derive the sources of organic aerosols. During the more extreme haze periods, 537 and 243 ug/m3 were recorded in Xi'an and Beijing respectively. The main results include a dominance of coal combustion in Beijing of the primary organic aerosols with a contribution of more than 90% to the cancerogenic polycyclic hydrocarbons. In Xi'an primary wood burning was a more important source. In both cities, an increase of secondary organic aerosols could be observed. The results including uncertainties will be discussed and put in perspective of previous analyses of haze in northern China including our previous analysis published in Nature (Huang et al., 2014). The study can be used as a role model for future similar analyses in Asia where the emission sources are highly complex. Huang, R.J., Cao, J.J., El Haddad, I. and Prévôt A.S.H. et al. (2014) Nature 514, 218-222. Williams, L.R., Prévôt, A.S.H., Worsnop, D.R. et al. (2013) Atmos. Meas. Tech. 6, 3271-3280.

  10. Composition and source apportionment of PM1 at urban site Kanpur in India using PMF coupled with CBPF

    Science.gov (United States)

    Rai, Pragati; Chakraborty, Abhishek; Mandariya, Anil Kumar; Gupta, Tarun

    2016-09-01

    This study addresses the three major questions: (1) what are the emission sources of PM1 which are affecting the study area; (2) where do these emission sources come from; and (3) is there any temporal variation in the emission sources. To address these issues, two advanced statistical methods are described in this paper. Identification of emission sources was performed by EPA PMF (v 5.0) and to understand the temporal variability, sampling was done for three winter seasons 2008-09, 2009-10 and 2011-12 within Kanpur city. To identify the possible source directions, Conditional Bivariate Probability function (CBPF) was used. The average PM1 concentration was higher in 2008-09 followed by 2011-12 and 2009-10 winter seasons. 2008-09 winter showed sources such as secondary sources mixed with power plant emission (42.8%), industrial emission (32.3%), coal combustion, brick kilns and vehicular emission (13.2%) and residual oil combustion and road dust (11.7%). The major contributors during winter season 2009-10 were secondary sources (33.1%), biomass burning (23.3%), heavy oil combustion (13%), vehicular emission mixed with crustal dust (11.3%), leather tanning industries (10.3%), industrial emission (4%), coal combustion and brick kilns (3.4%) and solid waste burning and incineration (1.5%) compared to secondary sources mixed with biomass burning (42.3%), industrial emission and crustal dust (35.1%) and vehicular emission and brick kilns (22.6%) during 2011-12 winter season. PMF model revealed that secondary sources were the main contributors for all the three winter seasons followed by biomass burning and power plant emission. The results of CBPF analysis agreed well with the locations of known local point sources., e.g. in the case of industrial emissions, the maximum probability was in the direction between NES direction where almost all the major industries are located in and around Kanpur while in the opposite direction the probability of biomass burning was high due to a rural area in NWS direction.

  11. Chemical apportionment of aerosol optical properties during the Asia-Pacific Economic Cooperation summit in Beijing, China

    Science.gov (United States)

    Han, Tingting; Xu, Weiqi; Chen, Chen; Liu, Xingang; Wang, Qingqing; Li, Jie; Zhao, Xiujuan; Du, Wei; Wang, Zifa; Sun, Yele

    2015-12-01

    We have investigated the chemical and optical properties of aerosol particles during the 2014 Asia-Pacific Economic Cooperation (APEC) summit in Beijing, China, using the highly time-resolved measurements by a high-resolution aerosol mass spectrometer and a cavity attenuated phase shift extinction monitor. The average (±σ) extinction coefficient (bext) and absorption coefficient (bap) were 186.5 (±184.5) M m-1 and 23.3 (±21.9) M m-1 during APEC, which were decreased by 63% and 56%, respectively, compared to those before APEC primarily due to strict emission controls. The aerosol composition and size distributions showed substantial changes during APEC; as a response, the mass scattering efficiency (MSE) of PM1 was decreased from 4.7 m2 g-1 to 3.5 m2 g-1. Comparatively, the average single-scattering albedo (SSA) remained relatively unchanged, illustrating the synchronous reductions of bext and bap during APEC. MSE and SSA were found to increase as function of the oxidation degree of organic aerosol (OA), indicating a change of aerosol optical properties during the aging processes. The empirical relationships between chemical composition and particle extinction were established using a multiple linear regression model. Our results showed the largest contribution of ammonium nitrate to particle extinction, accounting for 35.1% and 29.3% before and during APEC, respectively. This result highlights the important role of ammonium nitrate in the formation of severe haze pollution during this study period. We also observed very different optical properties of primary and secondary aerosol. Owing to emission controls in Beijing and surrounding regions and also partly the influences of meteorological changes, the average bext of secondary aerosol during APEC was decreased by 71% from 372.3 M m-1 to 108.5 M m-1, whereas that of primary aerosol mainly from cooking, traffic, and biomass burning emissions showed a smaller reduction from 136.7 M m-1 to 71.3 M m-1. As a result, the contribution of primary aerosol to particle extinction increased from 26.8% to 39.6%, elucidating an enhanced role of local primary sources in visibility deterioration during APEC. Further analysis of chemically resolved particle extinction showed that the extinction contributions of aerosol species varied greatly between different air masses but generally with ammonium nitrate, ammonium sulfate, and secondary OA being the three major contributors.

  12. Source apportionment and health risk assessment of PM10 in a naturally ventilated school in a tropical environment.

    Science.gov (United States)

    Mohamad, Noorlin; Latif, Mohd Talib; Khan, Md Firoz

    2016-02-01

    This study aimed to investigate the chemical composition and potential sources of PM10 as well as assess the potential health hazards it posed to school children. PM10 samples were taken from classrooms at a school in Kuala Lumpur's city centre (S1) and one in the suburban city of Putrajaya (S2) over a period of eight hours using a low volume sampler (LVS). The composition of the major ions and trace metals in PM10 were then analysed using ion chromatography (IC) and inductively coupled plasma-mass spectrometry (ICP-MS), respectively. The results showed that the average PM10 concentration inside the classroom at the city centre school (82µg/m(3)) was higher than that from the suburban school (77µg/m(3)). Principal component analysis-absolute principal component scores (PCA-APCS) revealed that road dust was the major source of indoor PM10 at both school in the city centre (36%) and the suburban location (55%). The total hazard quotient (HQ) calculated, based on the formula suggested by the United States Environmental Protection Agency (USEPA), was found to be slightly higher than the acceptable level of 1, indicating that inhalation exposure to particle-bound non-carcinogenic metals of PM10, particularly Cr exposure by children and adults occupying the school environment, was far from negligible. PMID:26590697

  13. Chemical characterization and source apportionment estimates of particulate matter collected within the framework of EU project HEPMEAP

    NARCIS (Netherlands)

    Bloemen HJT; Gerlofs-Nijland ME; Janssen NAH; Sandstrom T; Bree L van; Cassee FR; Umea University, Sweden; LMV; MGO; LOK

    2005-01-01

    The chemical composition of fine (0.1 - 2.5 um) and coarse mode (2.5 - 10 um) particulate matter is determined with specific attention paid to indicators of traffic emissions. Inorganic ions nitrate, sulphate and ammonium sum to 34% of PM mass and the measured organics from combustion processes up t

  14. Chemical composition of PM2.5 particles in Salamanca, Guanajuato Mexico: Source apportionment with receptor models

    Science.gov (United States)

    Herrera Murillo, Jorge; Campos Ramos, Arturo; Ángeles García, Felipe; Blanco Jiménez, Salvador; Cárdenas, Beatriz; Mizohata, Akira

    2012-04-01

    The National Institute of Ecology, through Management General for Environmental Research and Training (DGCENICA) carried out a sampling campaign where a total of 21 elements were determined in 140 PM2.5 samples from one sampling site located in the city of Salamanca, Guanajuato-Mexico between November 2006 and November 2007. The annual average PM2.5 concentration was 45 μg/m3 almost three times the Mexican Annual standard for PM2.5. Mineral, organic and elemental carbon were the most important components present in particles PM2.5. Two advanced receptor models, UNMIX and positive matrix factorization (PMF) were used for PM2.5 source identification. Four and six sources were identified by UNMIX and PMF, respectively, from a combined dataset including 15 chemical species. Source categories were determined based on both, component abundances in the source profiles, and their temporal characteristics. Overall, different sources were identified as the major contributors: heavy fuels combustion, traditional brick production-agricultural burning, crustal, road traffic and secondary organic aerosols.

  15. Source apportionment of submicron organic aerosols at an urban site by linear unmixing of aerosol mass spectra

    Directory of Open Access Journals (Sweden)

    V. A. Lanz

    2006-11-01

    Full Text Available Submicron ambient aerosol was characterized in summer 2005 at an urban background site in Zurich, Switzerland, during a three-week measurement campaign. Highly time-resolved samples of non-refractory aerosol components were analyzed with an Aerodyne aerosol mass spectrometer (AMS. Positive matrix factorization (PMF was used for the first time for AMS data to identify the main components of the total organic aerosol and their sources. The PMF retrieved factors were compared to measured reference mass spectra and were correlated with tracer species of the aerosol and gas phase measurements from collocated instruments. Six factors were found to explain virtually all variance in the data and could be assigned either to sources or to aerosol components such as oxygenated organic aerosol (OOA. Our analysis suggests that at the measurement site only a small (<10% fraction of organic PM1 originates from freshly emitted fossil fuel combustion. Other primary sources identified to be of similar or even higher importance are charbroiling (10–15% and wood burning (~10%, along with a minor source interpreted to be influenced by food cooking (6%. The fraction of all identified primary sources is considered as primary organic aerosol (POA. This interpretation is supported by calculated ratios of the modelled POA and measured primary pollutants such as elemental carbon (EC, NOx, and CO, which are in good agreement to literature values. A high fraction (60–69% of the measured organic aerosol mass is OOA which is interpreted mostly as secondary organic aerosol (SOA. This oxygenated organic aerosol can be separated into a highly aged fraction, OOA I, (40–50% with low volatility and a mass spectrum similar to fulvic acid, and a more volatile and probably less processed fraction, OOA II (on average 20%. This is the first publication of a multiple component analysis technique to AMS organic spectral data and also the first report of the OOA II component.

  16. Organic Aerosol source apportionment in London 2013 with ME-2: exploring the solution space with annual and seasonal analysis

    OpenAIRE

    Reyes-Villegas, Ernesto; Green, David C.; Priestman, Max; Canonaco, Francesco; Coe, Hugh; Prévôt, André S.H.; Allan, James D.

    2016-01-01

    The Multilinear Engine (ME-2) factorisation tool is being widely used following the recent development of the Source Finder (SoFi) interphase at PSI. However, the success of this tool, when using the a-value approach, largely depends on the inputs (i.e. target profiles) applied as well as the experience of the user. A strategy to explore the solution space is proposed to objectively determine the solution that best deconvolves the organic aerosol (OA) sources where trilinear regression has pr...

  17. [Distribution Characteristics and Source Apportionment of n-Alkanes in Water from Yellow River in Henan Section].

    Science.gov (United States)

    Feng, Jing-lan; Xi, Nan-nan; Zhang, Fei; Liu, Shu-hui; Sun, Jian-hui

    2016-03-15

    To investigate the distributions and possible sources of n-alkanes in water and suspended particulate matter from Yellow River in Henan section, 26 water and suspended particulate matter samples were collected in August 2010 and 22 n-alkanes (C₁₄-C₃₆) were quantitatively determined by gas chromatography-mass spectrometer (GC-MS). Potential sources of n-alkanes were analyzed using different characteristic parameters. The results indicated that total concentrations of 22 n-alkanes were 521-5,843 ng · L⁻¹ with a mean concentration of 1,409 ng · L⁻¹, while the total amounts of n-alkanes in the suspended particulate matter were 463-11,142 ng · L⁻¹ with a mean value of 1,951 ng · L⁻¹. The composition profiles of n-alkanes in water showed unimodal distribution with a peak at C₂₅ in water. However, the composition characteristics of n-alkanes in SPM were of bimodal type, but still with the advantage of high carbon hydrocarbons peak at C₂₅. Results of characteristic parameters including CPI, TAR, OEP and % WaxCn showed that n-alkanes in the studied area were derived mainly from combustion of fossil fuel, while terrestrial higher plant played a role in the existence of n-alkanes in water and suspended particulate matter from Yellow River in Henan section. PMID:27337879

  18. Source Apportionment of Particulate Matter (PM10 In an Integrated Coal Mining Complex of Jharia Coalfield, Eastern India, A Review.

    Directory of Open Access Journals (Sweden)

    Debananda Roy

    2014-04-01

    Full Text Available Coal based thermal power generation accounts for 44.7% of the world's electricity and coal alone provides about 80% of the total energy demand in India. Energy-intensive industries deteriorate the air quality of the residential areas due to release of different pollutants, especially a range of deleterious heavy metals like Hg, Cd, Cu, Pb, and Cr. Near about 53.3 percent of the coal produced every year in India has been used for thermal generation. Jharia Coalfield (JCF is major contributor of coking coal in India. JCF receives particulate matter from various sources such as, opencast coal mining and its associated activities, thermal power stations, automobiles, generator sets fuel burning, construction activities, domestic coal, cooking gas burning, etc. and even the background contribution of natural dust (crustal origin can not be ruled out, particularly, in the zones having loose topsoil. Concentration of particulate matter causes harmful impacts to the society. These multiple sources are contributing to particulates pollution in the study area.

  19. Bayesian Nitrate Source Apportionment to Individual Groundwater Wells in the Central Valley by Use of Elemental and Isotopic Tracers

    Science.gov (United States)

    Ransom, K.; Grote, M. N.; Deinhart, A.; Eppich, G.; Kendall, C.; Sanborn, M.; Souders, K.; Wimpenny, J.; Yin, Q. Z.; Young, M. B.; Harter, T.

    2015-12-01

    Groundwater quality is a concern in alluvial aquifers that underlie agricultural areas, such as in the San Joaquin Valley of California. Nitrate from fertilizers and animal waste can leach to groundwater and contaminate drinking water resources. Dairy manure and synthetic fertilizers are prevailing sources of nitrate in groundwater for the San Joaquin Valley with septic waste contributing as a major source in some areas. The rural population in the San Joaquin Valley relies almost exclusively on shallow domestic wells (less than 150 m deep), of which many have been affected by nitrate. Knowledge of the proportion of each of the three main nitrate sources (manure, synthetic fertilizer, and septic waste) contributing to individual well nitrate can aid future regulatory decisions. Mixing models quantify the proportional contributions of sources to a mixture by using the concentration of conservative tracers within each source as a source signature. Deterministic mixing models are common, but do not allow for variability in the tracer source concentration or overlap of tracer concentrations between sources. In contrast, Bayesian mixing models treat source contributions probabilistically, building statistical variation into the inferences for each well. The authors developed a Bayesian mixing model on a pilot network of 56 private domestic wells in the San Joaquin Valley for which nitrogen, oxygen, and boron isotopes as well as nitrate and iodine were measured. Nitrogen, oxygen, and boron isotopes as well as iodine can be used as tracers to differentiate between manure, fertilizers, septic waste, and natural sources of nitrate (which can contribute nitrate in concentrations up to 4 mg/L). In this work, the isotopic and elemental tracers were used to estimate the proportional contribution of manure, fertilizers, septic waste, and natural sources to overall groundwater nitrate concentration in individual wells. Prior distributions for the four tracers for each of the four sources were estimated based on end member measurements, literature, or as a part of our previous work. The Bayesian method produces estimates of the fractional source contributions to each well, which can be compared to surrounding landuse types. Estimated source contributions were broadly consistent with nearby landuse types in this sample.

  20. Source Apportionment of Annual Water Pollution Loads in River Basins by Remote-Sensed Land Cover Classification

    Directory of Open Access Journals (Sweden)

    Yi Wang

    2016-08-01

    Full Text Available In this study, in order to determine the efficiency of estimating annual water pollution loads from remote-sensed land cover classification and ground-observed hydrological data, an empirical model was investigated. Remote sensing data imagery from National Oceanic and Atmospheric Administration (NOAA Advanced Very High Resolution Radiometer were applied to an 11 year (1994–2004 water quality dataset for 30 different rivers in Japan. Six water quality indicators—total nitrogen (TN, total phosphorus (TP, biochemical oxygen demand (BOD, chemical oxygen demand (COD, and dissolved oxygen (DO—were examined by using the observed river water quality data and generated land cover map. The TN, TP, BOD, COD, and DO loads were estimated for the 30 river basins using the empirical model. Calibration (1994–1999 and validation (2000–2004 results showed that the proposed simulation technique was useful for predicting water pollution loads in the river basins. We found that vegetation land cover had a larger impact on TP export into all rivers. Urban areas had a very small impact on DO export into rivers, but a relatively large impact on BOD and TN export. The results indicate that the application of land cover data generated from the remote-sensed imagery could give a useful interpretation about the river water quality.

  1. Source apportionment and risk assessment of emerging contaminants: an approach of pharmaco-signature in water systems.

    Directory of Open Access Journals (Sweden)

    Jheng-Jie Jiang

    Full Text Available This paper presents a methodology based on multivariate data analysis for characterizing potential source contributions of emerging contaminants (ECs detected in 26 river water samples across multi-scape regions during dry and wet seasons. Based on this methodology, we unveil an approach toward potential source contributions of ECs, a concept we refer to as the "Pharmaco-signature." Exploratory analysis of data points has been carried out by unsupervised pattern recognition (hierarchical cluster analysis, HCA and receptor model (principal component analysis-multiple linear regression, PCA-MLR in an attempt to demonstrate significant source contributions of ECs in different land-use zone. Robust cluster solutions grouped the database according to different EC profiles. PCA-MLR identified that 58.9% of the mean summed ECs were contributed by domestic impact, 9.7% by antibiotics application, and 31.4% by drug abuse. Diclofenac, ibuprofen, codeine, ampicillin, tetracycline, and erythromycin-H2O have significant pollution risk quotients (RQ>1, indicating potentially high risk to aquatic organisms in Taiwan.

  2. Burial fluxes and source apportionment of carbon in culture areas of Sanggou Bay over the past 200 years

    Institute of Scientific and Technical Information of China (English)

    LIU Sai; HUANG Jiansheng; YANG Qian; YANG Shu; YANG Guipeng; SUN Yao

    2015-01-01

    In this study, we assessed the burial fluxes and source appointment of different forms of carbon in core sediments collected from culture areas in the Sanggou Bay, and preliminarily analyzed the reasons for the greater proportion of inorganic carbon burial fluxes (BFTIC). The average content of total carbon (TC) in the Sanggou Bay was 2.14%. Total organic carbon (TOC) accounted for a small proportion in TC, more than 65% of which derived from terrigenous organic carbon (Ct), and while the proportion of marine-derived organic carbon (Ca) increased significantly since the beginning of large-scale aquaculture. Total inorganic carbon (TIC) accounted for 60%–75%of TC, an average of which was 60%, with a maximum up to 90% during flourishing periods (1880–1948) of small natural shellfish derived from seashells inorganic carbon (Shell-IC). The TC burial fluxes ranged from 31 g/(m2·a) to 895 g/(m2·a) with an average of 227 g/(m2·a), which was dominated by TIC (about 70%). Shell-IC was the main source of TIC and even TC. As the main food of natural shellfish, biogenic silica (BSi) negatively correlated with BFTIC through affecting shellfish breeding. BFTIC of Sta. S1, influenced greatly by the Yellow Sea Coastal Current, had a certain response to Pacific Decadal Oscillation (PDO) in some specific periods.

  3. Source apportionment of wide range particle size spectra and black carbon collected at the airport of Venice (Italy)

    Science.gov (United States)

    Masiol, Mauro; Vu, Tuan V.; Beddows, David C. S.; Harrison, Roy M.

    2016-08-01

    Atmospheric particles are of high concern due to their toxic properties and effects on climate, and large airports are known as significant sources of particles. This study investigates the contribution of the Airport of Venice (Italy) to black carbon (BC), total particle number concentrations (PNC) and particle number size distributions (PNSD) over a large range (14 nm-20 μm). Continuous measurements were conducted between April and June 2014 at a site located 110 m from the main taxiway and 300 m from the runway. Results revealed no significantly elevated levels of BC and PNC, but exhibited characteristic diurnal profiles. PNSD were then analysed using both k-means cluster analysis and positive matrix factorization. Five clusters were extracted and identified as midday nucleation events, road traffic, aircraft, airport and nighttime pollution. Six factors were apportioned and identified as probable sources according to the size profiles, directional association, diurnal variation, road and airport traffic volumes and their relationships to micrometeorology and common air pollutants. Photochemical nucleation accounted for ∼44% of total number, followed by road + shipping traffic (26%). Airport-related emissions accounted for ∼20% of total PNC and showed a main mode at 80 nm and a second mode beyond the lower limit of the SMPS (factors accounted for less than 10% of number counts, but were relevant for total volume concentrations: nighttime nitrate, regional pollution and local resuspension. An analysis of BC levels over different wind sectors revealed no especially significant contributions from specific directions associated with the main local sources, but a potentially significant role of diurnal dynamics of the mixing layer on BC levels. The approaches adopted in this study have identified and apportioned the main sources of particles and BC at an international airport located in area affected by a complex emission scenario. The results may underpin measures for improving local and regional air quality, and health impact assessment studies.

  4. SOURCE APPORTIONMENT STUDIES OF PM-2.5 IN TWO CZECH CITIES: POSSIBLE USES IN HEALTH STUDIES

    Science.gov (United States)

    Aerosol and gas phase air pollutant measurements were made in two cities during an ongoing air pollution-health outcome study in the Czech Republic. Teplice, located in northwestern Bohemia, was selected because the local population was exposed to high air pollution levels. Prac...

  5. SOURCE APPORTIONMENT STUDIES OF PM-2.5 IN TWO CZECH CITIES: A COMPARISON OF DIFFERENT METHODS

    Science.gov (United States)

    Air monitoring data were obtained as part of an ongoing air pollution-health outcome study initiated in 1991. Teplice, located in northwestern Bohemia, was selected because the local population was exposed to high air pollution levels. Prachatice, located in southern Bohemia, w...

  6. Source apportionment of particles at Station Nord, North East Greenland during 2008–2010 using COPREM and PMF analysis

    DEFF Research Database (Denmark)

    Nguyen, Quynh; Skov, Henrik; Sørensen, Lise Lotte;

    2013-01-01

    , which were all influenced by metal industries. One anthropogenic source was dominated by Zn of which air mass back trajectories using the Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model suggested a Canadian Arctic origin, despite certain influences from Southern and Eastern......In order to develop strategies for controlling and reducing Arctic air pollution, there is a need to understand the basic mechanisms for determining the fate of air pollution in the Arctic. Sources of atmospheric particles at Station Nord (81° 36' N, 16° 40' W) in North East Greenland were...

  7. Source apportionment of size and time resolved trace elements and organic aerosols from an urban courtyard site in Switzerland

    Directory of Open Access Journals (Sweden)

    A. Richard

    2011-09-01

    Full Text Available Time and size resolved data of trace elements were obtained from measurements with a rotating drum impactor (RDI and subsequent X-ray fluorescence spectrometry. Trace elements can act as indicators for the identification of sources of particulate matter <10 μm (PM10 in ambient air. Receptor modeling was performed with positive matrix factorization (PMF for trace element data from an urban background site in Zürich, Switzerland. Eight different sources were identified for the three examined size ranges (PM1−0.1, PM2.5−1 and PM10−2.5: secondary sulfate, wood combustion, fire works, road traffic, mineral dust, de-icing salt, industrial and local anthropogenic activities. The major component was secondary sulfate for the smallest size range; the road traffic factor was found in all three size ranges. This trace element analysis is complemented with data from an Aerodyne high-resolution time-of-flight aerosol mass spectrometer (AMS, assessing the PM1 fraction of organic aerosols. A separate PMF analysis revealed three factors related to three of the sources found with the RDI: oxygenated organic aerosol (OOA, related to inorganic secondary sulfate, hydrocarbon-like organic aerosol (HOA, related to road traffic and biomass burning organic aerosol (BBOA, explaining 60 %, 22 % and 17 % of total measured organics, respectively. Since different compounds are used for the source classification, a higher percentage of the ambient PM10 mass concentration can be apportioned to sources by the combination of both methods.

  8. Source apportionment of size and time resolved trace elements and organic aerosols from an urban courtyard site in Switzerland

    Directory of Open Access Journals (Sweden)

    A. Richard

    2011-02-01

    Full Text Available Time and size resolved data of trace elements were obtained from measurements with a rotating drum impactor (RDI and subsequent X-ray fluorescence spectrometry. Trace elements can act as indicators for the identification of sources of particulate matter <10 μm (PM10 in ambient air. Receptor modeling was performed with positive matrix factorization (PMF for trace element data from an urban background site in Zürich, Switzerland. Eight different sources were identified for the three examined size ranges (PM1−0.1, PM2.5−1 and PM10−2.5: secondary sulfate, wood combustion, fire works, road traffic, mineral dust, de-icing salt, industrial and local anthropogenic activities. The major component was secondary sulfate for the smallest size range; the road traffic factor was found in all three size ranges. This trace element analysis is complemented with data from an Aerodyne high-resolution time-of-flight aerosol mass spectrometer (AMS, assessing the PM1 fraction of organic aerosols. A separate PMF analysis revealed three factors related to three of the sources found with the RDI: oxygenated organic aerosol (OOA, related to inorganic secondary sulfate, hydrocarbon like organic aerosol (HOA, related to road traffic and biomass burning organic aerosol (BBOA, explaining 60%, 22% and 17% of total measured organics, respectively. Since different compounds are used for the source classification, a higher percentage of the ambient PM10 mass concentration can be apportioned to sources by the combination of both methods.

  9. Spatial Distribution, Air-Water Fugacity Ratios and Source Apportionment of Polychlorinated Biphenyls in the Lower Great Lakes Basin.

    Science.gov (United States)

    Khairy, Mohammed; Muir, Derek; Teixeira, Camilla; Lohmann, Rainer

    2015-12-01

    Polychlorinated biphenyls (PCBs) continue to be contaminants of concern across the Great Lakes. It is unclear whether current concentrations are driven by ongoing primary emissions from their original uses, or whether ambient PCBs are dominated by their environmental cycling. Freely dissolved PCBs in air and water were measured using polyethylene passive samplers across Lakes Erie and Ontario during summer and fall, 2011, to investigate their spatial distribution, determine and apportion their sources and to asses their air-water exchange gradients. Average gaseous and freely dissolved ∑29 PCB concentrations ranged from 5.0 to 160 pg/m(3) and 2.0 to 55 pg/L respectively. Gaseous concentrations were significantly correlated (R(2) = 0.80) with the urban area within a 3-20 km radius. Fugacity ratios indicated that the majority of PCBs are volatilizing from the water thus acting as a secondary source for the atmosphere. Dissolved PCBs were probably linked to PCB emissions from contaminated sites and areas of concern. Positive matrix factorization indicated that although volatilized Aroclors (gaseous PCBs) and unaltered Aroclors (dissolved PCBs) dominate in some samples, ongoing non-Aroclor sources such as paints/pigments (PCB 11) and coal/wood combustion showed significant contributions across the lower Great Lakes. Accordingly, control strategies should give further attention to PCBs emitted from current use sources. PMID:25915412

  10. Source apportionment of wide range particle size spectra and black carbon collected at the airport of Venice (Italy)

    Science.gov (United States)

    Masiol, Mauro; Vu, Tuan V.; Beddows, David C. S.; Harrison, Roy M.

    2016-08-01

    Atmospheric particles are of high concern due to their toxic properties and effects on climate, and large airports are known as significant sources of particles. This study investigates the contribution of the Airport of Venice (Italy) to black carbon (BC), total particle number concentrations (PNC) and particle number size distributions (PNSD) over a large range (14 nm-20 μm). Continuous measurements were conducted between April and June 2014 at a site located 110 m from the main taxiway and 300 m from the runway. Results revealed no significantly elevated levels of BC and PNC, but exhibited characteristic diurnal profiles. PNSD were then analysed using both k-means cluster analysis and positive matrix factorization. Five clusters were extracted and identified as midday nucleation events, road traffic, aircraft, airport and nighttime pollution. Six factors were apportioned and identified as probable sources according to the size profiles, directional association, diurnal variation, road and airport traffic volumes and their relationships to micrometeorology and common air pollutants. Photochemical nucleation accounted for ∼44% of total number, followed by road + shipping traffic (26%). Airport-related emissions accounted for ∼20% of total PNC and showed a main mode at 80 nm and a second mode beyond the lower limit of the SMPS (international airport located in area affected by a complex emission scenario. The results may underpin measures for improving local and regional air quality, and health impact assessment studies.

  11. Particle sized-resolved source apportionment of primary and secondary organic tracer compounds at urban and rural locations in Spain

    Directory of Open Access Journals (Sweden)

    B. L. van Drooge

    2015-04-01

    Full Text Available Atmospheric particulate matter (PM was fractionated in six aerodynamic sizes, > 7.2, 7.2–3, 3–1.5, 1.5–1, 1–0.5, PM > 0.5 μm. Thus, markers of photochemically synthesized organic compounds or combustion sources, either biomass burning or traffic emissions, were predominantly observed in the fraction Important seasonal differences were observed at the rural site. In the PM > 0.5 μm fractions the differences involved predominant soil-sourced compounds in the warm period and mixed combustion sources, photochemical products and vegetation emissions in the cold. Multivariate Curve Resolution Alternating Least Squares showed that these organic aerosols essentially originated from six source components. Four of them reflected primary emissions related with either natural products, e.g. vegetation emissions and up whirled soil dust, or anthropogenic contributions, e.g. combustion products and compounds related with urban life-style activities, mainly vehicular exhausts and tobacco smoking. Two secondary organic aerosol components were identified. They accumulated in the smallest ( 0.5 μm and involved strong or mild photochemical transformations of vegetation precursor molecules, respectively. Toxicologically relevant information was also disclosed with the present approach. Thus, the strong predominance of biomass burning residues at the rural site during the cold period involved atmospheric concentrations of polycyclic aromatic hydrocarbons that were three times higher than at the urban sites and benzo[a]pyrene concentrations above legal recommendations.

  12. Monsoon rain chemistry and source apportionment using receptor modeling in and around National Capital Region (NCR) of Delhi, India

    Science.gov (United States)

    Tiwari, Suresh; Kulshrestha, U. C.; Padmanabhamurty, B.

    Studies on monsoon precipitation chemistry were carried out to understand the nature of rainwater and sources of pollution at eight different locations in and around the National Capital Region (NCR) of Delhi during southwest monsoon in the years 2003-2005. These sites were Bulandshahr (BUL), Garhmuktesar (GAR), Muradnagar (MUR), Sardhana (SAR), Panipat (PAN), Charkhi Dadri (CHA), Hodal (HOD) and Bahror (BAH). The rainwater samples, collected at these locations, were analyzed for major anions, cations and pH. The data were assessed for its quality. In general, the order of concentrations of major ions was observed to be: Ca 2+>SO 42->HCO 3->NH 4+>Cl ->NO 3->Na +>Mg 2+>K +>F -. The average pH of rainwater at these stations was observed to be 6.39, ranging from 5.77 to 6.62, indicating alkaline nature. However, a few rain events, 31% at Panipat, 12% at Muradnagar and 29% at Sardhana, were observed to be acidic (pHcattle, brick kilns and industries were reflected in third or fourth PC indicating moderate influence of anthropogenic activities in this region.

  13. Characterization and source apportionment of submicron aerosol with aerosol mass spectrometer during the PRIDE-PRD 2006 campaign

    Science.gov (United States)

    Xiao, R.; Takegawa, N.; Zheng, M.; Kondo, Y.; Miyazaki, Y.; Miyakawa, T.; Hu, M.; Shao, M.; Zeng, L.; Gong, Y.; Lu, K.; Deng, Z.; Zhao, Y.; Zhang, Y. H.

    2011-07-01

    Size-resolved chemical compositions of non-refractory submicron aerosol were measured using an Aerodyne quadrupole aerosol mass spectrometer (Q-AMS) at the rural site Back Garden (BG), located ~50 km northwest of Guangzhou in July 2006. This paper characterized the submicron aerosol particles of regional air pollution in Pearl River Delta (PRD) in the southern China. Organics and sulfate dominated the submicron aerosol compositions, with average mass concentrations of 11.8 ± 8.4 μg m-3 and 13.5 ± 8.7 μg m-3, respectively. Unlike other air masses, the air masses originated from Southeast-South and passing through the PRD urban areas exhibited distinct bimodal size distribution characteristics for both organics and sulfate: the first mode peaked at vacuum aerodynamic diameters (Dva) ∼200 nm and the second mode occurred at Dva from 300-700 nm. With the information from AMS, it was found from this study that the first mode of organics in PRD regional air masses was contributed by both secondary organic aerosol formation and combustion-related emissions, which is different from most findings in other urban areas (first mode of organics primarily from combustion-related emissions). The analysis of AMS mass spectra data by positive matrix factorization (PMF) model identified three sources of submicron organic aerosol including hydrocarbon-like organic aerosol (HOA), low volatility oxygenated organic aerosol (LV-OOA) and semi-volatile oxygenated organic aerosol (SV-OOA). The strong correlation between HOA and EC indicated primary combustion emissions as the major source of HOA while a close correlation between SV-OOA and semi-volatile secondary species nitrate as well as between LV-OOA and nonvolatile secondary species sulfate suggested secondary aerosol formation as the major source of SV-OOA and LV-OOA at the BG site. However, LV-OOA was more aged than SV-OOA as its spectra was highly correlated with the reference spectra of fulvic acid, an indicator of aged and oxygenated aerosol. The origin of HOA and OOA (the sum of LV-OOA and SV-OOA) has been further confirmed by the statistics that primary organic carbon (POC) and secondary organic carbon (SOC), estimated by the EC tracer method, were closely correlated with HOA and OOA, respectively. The results of the EC tracer method and of the PMF model revealed that primary organic aerosol (POA) constituted ~34-47 % of OA mass and secondary organic aerosol (SOA) constituted ~53-66 % of regional organic aerosol in PRD during summer season. The presence of abundant SOA was consistent with water soluble organic carbon (WSOC) results (accounting for ~60 % of OC on average) by Miyazaki et al. (2009) for the same campaign. OOA correlated well with WSOC at the BG site, indicating that most OOA were water soluble. More specifically, approximately 86 % of LV-OOA and 61 % of SV-OOA were estimated as water soluble species on the basis of carbon content comparison.

  14. Measurements and source apportionment of particle-associated polycyclic aromatic hydrocarbons in ambient air in Riyadh, Saudi Arabia

    Science.gov (United States)

    Bian, Qijing; Alharbi, Badr; Collett, Jeffrey; Kreidenweis, Sonia; Pasha, Mohammad J.

    2016-07-01

    Ambient air samples were obtained in Riyadh, the capital and largest city of Saudi Arabia, during two measurement campaigns spanning September 2011 to September 2012. Sixteen particle-phase polycyclic aromatic hydrocarbons (PAH) were quantified in 167 samples. Pyrene and fluoranthene were the most abundant PAH, with average of 3.37 ± 14.01 ng m-3 and 8.00 ± 44.09 ng m-3, respectively. A dominant contribution from low molecular weight (LMW) PAH (MW oil combustion emissions dominated total PAH concentrations, accounting for on average 96%, likely due to widespread use of oil fuels in energy production (power plants and industries). Our results demonstrate the significant influence of petroleum product production and consumption on particulate-phase PAH concentrations in Riyadh, but also point to the importance of traffic and solid fuel burning, including coke burning and seasonal biomass burning, especially as they contribute to the ambient levels of HMW PAH.

  15. Source apportionment of the carcinogenic potential of polycyclic aromatic hydrocarbons (PAH) associated to airborne PM10 by a PMF model.

    Science.gov (United States)

    Callén, M S; Iturmendi, A; López, J M; Mastral, A M

    2014-02-01

    In order to perform a study of the carcinogenic potential of polycyclic aromatic hydrocarbons (PAH), benzo(a)pyrene equivalent (BaP-eq) concentration was calculated and modelled by a receptor model based on positive matrix factorization (PMF). Nineteen PAH associated to airborne PM10 of Zaragoza, Spain, were quantified during the sampling period 2001-2009 and used as potential variables by the PMF model. Afterwards, multiple linear regression analysis was used to quantify the potential sources of BaP-eq. Five sources were obtained as the optimal solution and vehicular emission was identified as the main carcinogenic source (35 %) followed by heavy-duty vehicles (28 %), light-oil combustion (18 %), natural gas (10 %) and coal combustion (9 %). Two of the most prevailing directions contributing to this carcinogenic character were the NE and N directions associated with a highway, industrial parks and a paper factory. The lifetime lung cancer risk exceeded the unit risk of 8.7 x 10(-5) per ng/m(3) BaP in both winter and autumn seasons and the most contributing source was the vehicular emission factor becoming an important issue in control strategies. PMID:24022101

  16. A methodology to select particle morpho-chemical characteristics to use in source apportionment of particulate matter from livestock houses

    NARCIS (Netherlands)

    Cambra-Lopez, M.; Hermosilla, T.; Aarnink, A.; Ogink, N.W.M.

    2012-01-01

    Intensive poultry and pig houses are major point sources of particulate matter (PM) emissions. The knowledge on the contribution of individual sources to PM in different fractions is essential to improve PM reduction from livestock houses. We developed a methodology to investigate which input data (

  17. Chemical characteristics and source apportionment of PM10 during a brown haze episode in Harbin,China

    Institute of Scientific and Technical Information of China (English)

    Likun Huang; Chung-Shin Yuan; Guangzhi Wang; Kun Wang

    2011-01-01

    This study investigates the correlation between PM10 and meteorological factors such as wind speed,atmospheric visibility,dew point,relative humidity,and ambient temperature during a brown haze episode. In order to identify the potential sources of PM10 during brown haze episode,respirable particulate matter (PM10) was collected during both non-haze days and haze days and further analyzed for metallic elements,ionic species,and carbonaceous contents. Among them,ionic species contributed 45-64% to PM10,while metallic elements contributed 7-21% to PM10 which was smaller than the other chemical constituents. The average OC/EC ratio (42) in haze days was about three times of the average OC/EC ratio (14) in non-haze days. By using chemical mass balance (CMB) receptor model,the major sources were apportioned,including traffics,incinerators,coal combustion,steel industry,petrochemical industry,and secondary aerosols,etc. The contribution to PM10 concentration of each source was calculated for all the samples collected. The results showed that coal combustion was the major source of PM10 in non-haze days and secondary aerosols were the major source in haze days,followed by petrochemical industry,incinerators,and traffics,while other sources had negligible effect.

  18. Evaluation and Source Apportionment of Heavy Metals (HMs) in Sewage Sludge of Municipal Wastewater Treatment Plants (WWTPs) in Shanxi, China

    OpenAIRE

    Baoling Duan; Fenwu Liu; Wuping Zhang; Haixia Zheng; Qiang Zhang; Xiaomei Li; Yushan Bu

    2015-01-01

    Heavy metals (HMs) in sewage sludge have become the crucial limiting factors for land use application. Samples were collected and analyzed from 32 waste water treatment plants (WWTPs) in the Shanxi Province, China. HM levels in sewage sludge were assessed. The multivariate statistical method principal component analysis (PCA) was applied to identify the sources of HMs in sewage sludge. HM pollution classes by geochemical accumulation index Igeo and correlation analyses between HMs were also c...

  19. 42 CFR 411.47 - Apportionment of a lump-sum compromise settlement of a workers' compensation claim.

    Science.gov (United States)

    2010-10-01

    ... SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICARE PROGRAM EXCLUSIONS FROM MEDICARE AND LIMITATIONS ON MEDICARE PAYMENT Limitations on Medicare Payment for Services Covered Under Workers' Compensation...' compensation but not covered under Medicare. (2) Then to any beneficiary payments for services payable......

  20. Temporal variations and source apportionment of Hulis-C in PM2.5 in urban Shanghai.

    Science.gov (United States)

    Zhao, Mengfei; Qiao, Ting; Li, Yulan; Tang, Xiaoxing; Xiu, Guangli; Yu, Jian Zhen

    2016-11-15

    Humic-like substances (Hulis), the hydrophobic part of water-soluble organic compounds, have been recognized to play important roles in environmental behavior of PM2.5 in atmosphere. In this study, Hulis and other components of PM2.5, collected in urban Shanghai from September 2013 to August 2014 were analyzed. The annual average concentration of Hulis carbon (Hulis-C) was (2.61±2.58) μg/m(3), accounting for about 50% of water-soluble organic carbon (WSOC). The monthly average Hulis-C concentration peaked in December while the lowest was in summer, coinciding with the high and low of levoglucosan and secondary inorganic aerosol (SIA). Biomass burning and secondary formation were both important sources of Hulis-C, and their contributions showed obvious seasonality. In late autumn and winter, the strong inter-correlations among Hulis-C concentrations, NO3(-)/SO4(2-) mass ratios and nitrogen oxidation ratios (NOR) were found, suggesting the atmospheric oxidation of NOx to nitrate and related gas-phase reactions may be inter-linked with Hulis-C formation. In summer, photochemical reaction was clearly the major source of Hulis-C. The investigation by backward trajectory analysis showed that the long-range transport from the Northwest brought large amounts of PM2.5 and enhanced Hulis-C and levoglucosan level, indicating biomass burning as a significant source of Hulis-C under this type of synoptic weather conditions. In comparison, Hulis formation associated with the NOx oxidation pathway was mainly associated with the short-range transport from the neighboring cities. Marine aerosol was relatively clean and had little effects on Hulis-C. The CWT (concentration weighted trajectory) model results suggested that the Yangtze River Delta (YRD) region was an important source region of Hulis-C, while the effect of some northwestern areas was not negligible.

  1. Source apportionment of the particulate PAHs at Seoul, Korea: impact of long range transport to a megacity

    Directory of Open Access Journals (Sweden)

    J. Y. Lee

    2007-07-01

    Full Text Available Northeast Asia including China, Korea, and Japan is one of the world's largest fossil fuel consumption regions. Seoul, Korea, is a megacity in Northeast Asia. Its emissions of air pollutants can affect the region, and in turn it is also affected by regional emissions. To understand the extent of these influences, major sources of ambient particulate PAHs in Seoul were identified and quantified based on measurements made between August 2002 and December 2003. The chemical mass balance (CMB model was applied. Seven major emission sources were identified based on the emission data in Seoul and Northeast Asia: Gasoline and diesel vehicles, residential coal use, coke ovens, coal power plants, biomass burning, and natural gas (NG combustion. The major sources of particulate PAHs in Seoul during the whole measurement period were gasoline and diesel vehicles, together accounted for 31% of the measured particulate PAHs levels. However, the source contributions showed distinct daily and seasonal variations. High contributions of biomass burning and coal (residential and coke oven were observed in fall and winter, accounting for 63% and 82% of the total concentration of PAHs, respectively. Since these sources were not strong in and around Seoul, they are likely to be related to transport from outside of Seoul, from China and/or North Korea. This implies that the air quality in a mega-city such as Seoul can be influenced by the long range transport of air pollutants such as PAHs.

  2. Source apportionment of the particulate PAHs at Seoul, Korea: impact of long range transport to a megacity

    Directory of Open Access Journals (Sweden)

    J. Y. Lee

    2007-01-01

    Full Text Available Northeast Asia including China, Korea, and Japan is one of the world's largest fossil fuel consumption regions. Seoul is a megacity in Northeast Asia and its emissions of air pollutants can affect the region and is also affected by the regional emissions. To understand the degree of this relationship, major sources of ambient particulate PAHs at Seoul, Korea were identified and quantified based on the measurement data between August 2002 and December 2003. The chemical mass balance (CMB model was applied. Seven major emission sources were identified based on the emission data in Seoul and Northeast Asia: Gasoline and diesel vehicles, coal residential, coke oven, coal power plant, biomass burning, natural gas (NG combustion. The major source of particulate PAHs at Seoul on the whole measurement period was gasoline and diesel vehicles, accounted for 31% of the measured particulate PAHs levels. However, the source contributions showed distinct seasonal variations. High contributions of biomass burning and coal (residential and coke oven were shown in fall and winter accounted for 63% and 82% of the total PAHs concentration, respectively. Since these sources were not strong in and around Seoul, these might be related to transport from outside of Seoul, from China and/or North Korea. It implies that the air quality in the large urban city such as Seoul can be influenced by the long range transport of air pollutants such as PAHs.

  3. Radiocarbon-based source apportionment of black carbon (BC) in PM 10 aerosols from residential area of suburban Tokyo

    Science.gov (United States)

    Uchida, Masao; Kumata, Hidetoshi; Koike, Yasuyo; Tsuzuki, Mikio; Uchida, Tatsuya; Fujiwara, Kitao; Shibata, Yasuyuki

    2010-04-01

    The AMS technique was applied to analyse black carbon (BC), total organic carbon (TOC), and previously reported polycyclic aromatic hydrocarbons (PAHs) in PM 10 aerosols from a residential area, suburban Tokyo, to determine natural abundance of radiocarbon ( 14C), an ideal tracer to distinguish fossil fuel ( 14C-free) from modern biomass combustion sources of pyrolytic products. The 14C concentrations in BC, isolated using the CTO-375 method, were 42% and 30% pMC (in terms of percent Modern Carbon: pMC) in summer and winter, respectively. The 14C concentrations in BC were also compared with those of compound-class specific 14C content of PAHs previously reported for the same samples: they were 45% and 33% pMC in summer and winter, respectively. The 14C signals of BC were identical to those of high molecular weight (MW ⩾ 226, 5-6 rings) PAHs. The resemblance between 14C signals of BC and PAHs can be referred as a 'certificate' for the validity of the BC isolation method employed in this study. Also, it suggests that 14C-BC approach can be a surrogate for PAHs specific 14C analyses to monitor seasonal source variation of combustion-derived pyrolytic products. On the other hand, 14C contents of total organic carbon in 2004 were 61% and 42% pMC in summer and winter, respectively. This is likely attributed to higher contribution of plant activity in summer.

  4. Source Apportionment of Background PAHs in the Peace-Athabasca Delta (Alberta, Canada) Using Molecular Level Radiocarbon Analysis.

    Science.gov (United States)

    Jautzy, Josué J; Ahad, Jason M E; Hall, Roland I; Wiklund, Johan A; Wolfe, Brent B; Gobeil, Charles; Savard, Martine M

    2015-08-01

    The downstream accumulation of polycyclic aromatic hydrocarbons (PAHs) in the Peace-Athabasca Delta (PAD), an ecologically important landscape, is a key issue of concern given the rapid development of the oil sands industry in Northern Alberta, Canada. In addition to PAHs derived from industrial activity (i.e., oil sands mining) within the Athabasca watershed, however, forest fires and erosion of fossil fuel deposits within both the Athabasca and Peace watersheds are two potentially important natural sources of PAHs delivered to the PAD. Consequently, evaluating the environmental impact of mining activities requires a quantitative understanding of natural, background PAHs. Here, we utilize molecular-level natural-abundance radiocarbon measurements on an amalgamated sediment record from a Peace River flood-susceptible oxbow lake in the northern Peace sector of the PAD to quantitatively discriminate sources of naturally occurring alkylated PAHs (fossil and modern biomass). A radiocarbon mass balance quantified a predominantly natural petrogenic source (93% petrogenic, 7% forest fire) for alkylated PAHs during the past ∼50 years. Additionally, a significant petrogenic component determined for retene, a compound usually considered a biomarker for softwood combustion, suggests that its use as a unique forest fire indicator may not be suitable in PAD sediments receiving Peace watershed-derived fluvial inputs. PMID:26115178

  5. PM10 source apportionment applying PMF and chemical tracer analysis to ship-borne measurements in the Western Mediterranean

    Science.gov (United States)

    Bove, M. C.; Brotto, P.; Calzolai, G.; Cassola, F.; Cavalli, F.; Fermo, P.; Hjorth, J.; Massabò, D.; Nava, S.; Piazzalunga, A.; Schembari, C.; Prati, P.

    2016-01-01

    A PM10 sampling campaign was carried out on board the cruise ship Costa Concordia during three weeks in summer 2011. The ship route was Civitavecchia-Savona-Barcelona-Palma de Mallorca-Malta (Valletta)-Palermo-Civitavecchia. The PM10 composition was measured and utilized to identify and characterize the main PM10 sources along the ship route through receptor modelling, making use of the Positive Matrix Factorization (PMF) algorithm. A particular attention was given to the emissions related to heavy fuel oil combustion by ships, which is known to be also an important source of secondary sulphate aerosol. Five aerosol sources were resolved by the PMF analysis. The primary contribution of ship emissions to PM10 turned out to be (12 ± 4)%, while secondary ammonium sulphate contributed by (35 ± 5)%. Approximately, 60% of the total sulphate was identified as secondary aerosol while about 20% was attributed to heavy oil combustion in ship engines. The measured concentrations of methanesulphonic acid (MSA) indicated a relevant contribution to the observed sulphate loading by biogenic sulphate, formed by the atmospheric oxidation of dimethyl sulphide (DMS) emitted by marine phytoplankton.

  6. Bayesian nitrate source apportionment to individual groundwater wells in the Central Valley by use of elemental and isotopic tracers

    Science.gov (United States)

    Ransom, Katherine M.; Grote, Mark N.; Deinhart, Amanda; Eppich, Gary; Kendall, Carol; Sanborn, Matthew E.; Souders, A. Kate; Wimpenny, Joshua; Yin, Qing-zhu; Young, Megan; Harter, Thomas

    2016-07-01

    Groundwater quality is a concern in alluvial aquifers that underlie agricultural areas, such as in the San Joaquin Valley of California. Shallow domestic wells (less than 150 m deep) in agricultural areas are often contaminated by nitrate. Agricultural and rural nitrate sources include dairy manure, synthetic fertilizers, and septic waste. Knowledge of the relative proportion that each of these sources contributes to nitrate concentration in individual wells can aid future regulatory and land management decisions. We show that nitrogen and oxygen isotopes of nitrate, boron isotopes, and iodine concentrations are a useful, novel combination of groundwater tracers to differentiate between manure, fertilizers, septic waste, and natural sources of nitrate. Furthermore, in this work, we develop a new Bayesian mixing model in which these isotopic and elemental tracers were used to estimate the probability distribution of the fractional contributions of manure, fertilizers, septic waste, and natural sources to the nitrate concentration found in an individual well. The approach was applied to 56 nitrate-impacted private domestic wells located in the San Joaquin Valley. Model analysis found that some domestic wells were clearly dominated by the manure source and suggests evidence for majority contributions from either the septic or fertilizer source for other wells. But, predictions of fractional contributions for septic and fertilizer sources were often of similar magnitude, perhaps because modeled uncertainty about the fraction of each was large. For validation of the Bayesian model, fractional estimates were compared to surrounding land use and estimated source contributions were broadly consistent with nearby land use types.

  7. Chemical characterization and source apportionment estimates of particulate matter collected within the framework of EU project HEPMEAP

    OpenAIRE

    Bloemen HJT; Gerlofs-Nijland ME; Janssen NAH; Sandstrom T; Bree L van; Cassee FR; LVM; MGO; LOK

    2005-01-01

    Een groot deel van de massa van het fijnstof bestaat uit anorganisch aerosol (34% nitraat, sulfaat en ammonium). Daarnaast bestaat circa 2% uit organisch materiaal afkomstig van verbrandingsprocessen. Ruwe schattingen van de verkeersbijdrage voor deze twee fracties varieren tussen 30% en 60%. In het kader van het project 'Health effects of particles from motor engine exhaust and ambient pollution - HEPMEAP', een unieke Europese samenwerking tussen toxicologen en epidemiologen, is bu...

  8. Source Apportionment and Risk Assessment of Emerging Contaminants: An Approach of Pharmaco-Signature in Water Systems

    OpenAIRE

    Jheng-Jie Jiang; Chon-Lin Lee; Meng-Der Fang; Boyd, Kenneth G.; Gibb, Stuart W.

    2015-01-01

    This paper presents a methodology based on multivariate data analysis for characterizing potential source contributions of emerging contaminants (ECs) detected in 26 river water samples across multi-scape regions during dry and wet seasons. Based on this methodology, we unveil an approach toward potential source contributions of ECs, a concept we refer to as the "Pharmaco-signature." Exploratory analysis of data points has been carried out by unsupervised pattern recognition (hierarchical clu...

  9. Source apportionment of atmospheric ammonia before, during, and after the 2014 APEC summit in Beijing using stable nitrogen isotope signatures

    Science.gov (United States)

    Chang, Yunhua; Liu, Xuejun; Deng, Congrui; Dore, Anthony J.; Zhuang, Guoshun

    2016-09-01

    Stable nitrogen isotope composition (δ15N) offers new opportunities to address the long-standing and ongoing controversy regarding the origins of ambient ammonia (NH3), a vital precursor of PM2.5 (particulate matters with aerodynamic diameter equal or less than 2.5 µm) inorganic components, in the urban atmosphere. In this study, the δ15N values of NH3 samples collected from various sources were constrained using a novel and robust chemical method coupled with standard elemental analysis procedures. Independent of the wide variation in mass concentrations (ranging from 33 (vehicle) to over 6000 (human excreta) µg m-3), different NH3 sources have generally different δ15N values (ranging from -52.0 to -9.6 ‰). Significantly high δ15N values are seen as a characteristic feature of all vehicle-derived NH3 samples (-14.2 ± 2.8 ‰), which can be distinguished from other sources emitted at environmental temperature (-29.1 ± 1.7, -37.8 ± 3.6, and -50.0 ± 1.8 ‰ for livestock, waste, and fertilizer, respectively). The isotope δ15N signatures for a range of NH3 emission sources were used to evaluate the contributions of the different sources within measured ambient NH3 in Beijing, using an isotope mixing model (IsoSource). The method was used to quantify the sources of ambient NH3 before, during and after the 2014 Asia-Pacific Economic Cooperation (APEC) summit, when a set of stringent air quality control measures were implemented. Results show that the average NH3 concentrations (the overall contributions of traffic, waste, livestock, and fertilizer) during the three periods were 9.1 (20.3, 28.3, 23.6, and 27.7 %), 7.3 (8.8, 24.9, 14.3, and 52.0 %), and 12.7 (29.4, 23.6, 31.7, and 15.4 %) µg m-3, respectively, representing a 20.0 % decrease first and then a 74.5 % increase in overall NH3 mass concentrations. During (after) the summit, the contributions of traffic, waste, livestock, and fertilizer decreased (increased) by 56.7 (234.2), 12.0 (-5.0), 39.4 (120.8), and -87.7 % (-70.5 %) when compared with periods before (during) the summit, respectively, signifying that future NH3 control efforts in megacities like Beijing should prioritize traffic sector as well as livestock breeding. The results show that isotope ratio measurements of NH3 to be a valuable tool to quantify the atmospheric sources of NH3 in urban atmospheres.

  10. Source apportionment of methane using a triple isotope approach - Method development and application in the Baltic Sea

    Science.gov (United States)

    Steinbach, Julia; Holmstrand, Henry; Semiletov, Igor; Shakhova, Natalia; Shcherbakova, Kseniia; Kosmach, Denis; Sapart, Célia J.; Gustafsson, Örjan

    2015-04-01

    We present a method for measurements of the stable and radiocarbon isotope systems of methane in seawater and sediments. The triple isotope characterization of methane is useful in distinguishing different sources and for improving our understanding of biogeochemical processes affecting methane in the water column. D14C-CH4 is an especially powerful addition to stable isotope analyses in distinguishing between thermogenic and biogenic origins of the methane. Such measurements require large sample sizes, due to low natural abundance of the radiocarbon in CH4. Our system for sample collection, methane extraction and purification builds on the approach by Kessler and Reeburgh (Limn. & Ocean. Meth., 2005). An in-field system extracts methane from 30 -120 l water or 1-2 l sediment (depending on the in-situ methane concentration) by purging the samples with Helium to transfer the dissolved methane to the headspace and circulating it through cryogenically cooled absorbent traps where methane is collected. The in-field preparation eliminates the risks of storage and transport of large seawater quantities and subsequent leakage of sample gas as well as ongoing microbial processes and chemical reactions that may alter the sample composition. In the subsequent shore-based treatment, a laboratory system is used to purify and combust the collected CH4 to AMS-amenable CO2. Subsamples from the methane traps are analyzed for stable isotopes and compared to stable isotope measurements directly measured from small water samples taken in parallel, to correct for any potential fractionation occurring during this process. The system has been successfully tested and used on several shorter shipboard expeditions in the Baltic Sea and on a long summer expedition across the Arctic Ocean. Here we present the details of the method and testing, as well as first triple isotope field data from two cruises to the Landsort Deep area in the Central Baltic Sea.

  11. Source apportionment of the ambient PM2.5 across St. Louis using constrained positive matrix factorization

    NARCIS (Netherlands)

    Amato, F.; Hopke, P.K.

    2012-01-01

    In most cases, receptor models are applied to data from a single monitoring site even if there are multiple sampling locations in a given urban area. When it can be reasonably expected that the sites are affected by the same set of sources, it is possible to use the spatial variability of the source

  12. Source apportionment and spatial variability of PM2.5 using measurements at five sites in the Netherlands

    NARCIS (Netherlands)

    Mooibroek, D.; Schaap, M.; Weijers, E.P.; Hoogerbrugge, R.

    2011-01-01

    The Netherlands is considered one of the hotspot areas in Europe with high concentrations of particulate matter (PM) and may not be able to meet all standards for PM2.5 in time with current legislation (Matthijsen et al., 2009). To improve our understanding of the composition, distribution and origi

  13. Source apportionment of PM10 and PM2.5 in a desert region in northern Chile

    International Nuclear Information System (INIS)

    Estimating contributions of anthropogenic sources to ambient particulate matter (PM) in desert regions is a challenging issue because wind erosion contributions are ubiquitous, significant and difficult to quantify by using source-oriented, dispersion models. A receptor modeling analysis has been applied to ambient PM10 and PM2.5 measured in an industrial zone ∼ 20 km SE of Antofagasta (23.63°S, 70.39°W), a midsize coastal city in northern Chile; the monitoring site is within a desert region that extends from northern Chile to southern Perú. Integrated 24-hour ambient samples of PM10 and PM2.5 were taken with Harvard Impactors; samples were analyzed by X Ray Fluorescence, ionic chromatography (NO3− and SO4=), atomic absorption (Na+, K+) and thermal optical transmission for elemental and organic carbon determination. Receptor modeling was carried out using Positive Matrix Factorization (US EPA Version 3.0); sources were identified by looking at specific tracers, tracer ratios, local winds and wind trajectories computed from NOAA's HYSPLIT model. For the PM2.5 fraction, six contributions were found — cement plant, 33.7 ± 1.3%; soil dust, 22.4 ± 1.6%; sulfates, 17.8 ± 1.7%; mineral stockpiles and brine plant, 12.4 ± 1.2%; Antofagasta, 8.5 ± 1.3% and copper smelter, 5.3 ± 0.8%. For the PM10 fraction five sources were identified — cement plant, 38.2 ± 1.5%; soil dust, 31.2 ± 2.3%; mineral stockpiles and brine plant, 12.7 ± 1.7%; copper smelter, 11.5 ± 1.6% and marine aerosol, 6.5 ± 2.4%. Therefore local sources contribute to ambient PM concentrations more than distant sources (Antofagasta, marine aerosol) do. Soil dust is enriched with deposition of marine aerosol and calcium, sulfates and heavy metals from surrounding industrial activities. The mean contribution of suspended soil dust to PM10 is 50 μg/m3 and the peak daily value is 104 μg/m3. For the PM2.5 fraction, suspended soil dust contributes with an average of 9.3 μg/m3 and a peak daily value of 31.5 μg/m3. - Highlights: ► Ambient PM10 and PM2.5 were measured in an industrial zone within an arid region in South America. ► Dry climate allows accumulation of heavy metals deposited on the ground. ► Soil dust becomes enriched with tracers of anthropogenic activities. ► Average suspended soil dust reaches 9 μg/m3 for PM2.5 and 50 μg/m3 for PM10. ► Peak daily soil dust reaches 31.5 μg/m3 for PM2.5 and 104 μg/m3 for PM10

  14. Legislative Districts - Senate Districts

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This layer represents the Arkansas State Senate district boundaries adopted by the Arkansas Board of Apportionment on July 29, 2011. The Board of Apportionment,...

  15. Source apportionment vs. emission inventories of non-methane hydrocarbons (NMHC) in an urban area of the Middle East: local and global perspectives

    OpenAIRE

    Salameh, T.; Sauvage, S.; C. Afif; Borbon, A.; Locoge, N.

    2015-01-01

    We applied the Positive Matrix Factorization model to two large datasets collected during two intensive measurement campaigns (summer 2011 and winter 2012) at a sub-urban site in Beirut, Lebanon, in order to identify NMHC sources and quantify their contribution to ambient levels. Six factors were identified in winter and five factors in summer. PMF-resolved source profiles were consistent with source profiles established by near-field measurements. The major...

  16. Source apportionment vs. emission inventories of non-methane hydrocarbons (NMHC) in an urban area of the Middle East: local and global perspectives

    OpenAIRE

    Salameh, Thérèse; Sauvage, Stéphane; Afif, Charbel; Borbon, Agnès; Locoge, Nadine

    2016-01-01

    We applied the positive matrix factorization model to two large data sets collected during two intensive measurement campaigns (summer 2011 and winter 2012) at a sub-urban site in Beirut, Lebanon, in order to identify NMHC (non-methane hydrocarbons) sources and quantify their contribution to ambient levels. Six factors were identified in winter and five factors in summer. PMF-resolved source profiles were consistent with source profiles established by near-field measureme...

  17. Characterization and source apportionment of atmospheric organic and elemental carbon during fall and winter of 2003 in Xi'an, China

    Directory of Open Access Journals (Sweden)

    J. J. Cao

    2005-01-01

    Full Text Available Continuous measurements of atmospheric organic and elemental carbon (OC and EC were taken during the high-pollution fall and winter seasons at Xi'an, Shaanxi Province, China from September 2003 through February 2004. Battery-powered mini-volume samplers collected PM2.5 samples daily and PM10 samples every third day. Samples were also obtained from the plumes of residential coal combustion, motor-vehicle exhaust, and biomass burning sources. These samples were analyzed for OC/EC by thermal/optical reflectance (TOR following the Interagency Monitoring of Protected Visual Environments (IMPROVE protocol. OC and EC levels at Xi'an are higher than most urban cities in Asia. Average PM2.5 OC concentrations in fall and winter were 34.1±18.0 μg m−3 and 61.9±;33.2 μg m−3, respectively; while EC concentrations were 11.3±6.9 μg m−3 and 12.3±5.3 μg m−3, respectively. Most of the OC and EC were in the PM2.5 fraction. OC was strongly correlated (R>0.95 with EC in the autumn and moderately correlated (R=0.81 with EC during winter. Carbonaceous aerosol (OC×1.6+EC accounted for 48.8%±10.1% of the PM2.5 mass during fall and 45.9±7.5% during winter. The average OC/EC ratio was 3.3 in fall and 5.1 in winter, with individual OC/EC ratios nearly always exceeding 2.0. The higher wintertime OC/EC corresponded to increased residential coal combustion for heating. Total carbon (TC was associated with source contributions using absolute principal component analysis (APCA with eight thermally-derived carbon fractions. During fall, 73% of TC was attributed to gasoline engine exhaust, 23% to diesel exhaust, and 4% to biomass burning. During winter, 44% of TC was attributed to gasoline engine exhaust, 44% to coal burning, 9% to biomass burning, and 3% to diesel engine exhaust.

  18. Mexico City Aerosol Analysis during MILAGRO using High Resolution Aerosol Mass Spectrometry at the Urban Supersite (T0). Part 1: Fine Particle Composition and Organic Source Apportionment

    Energy Technology Data Exchange (ETDEWEB)

    Aiken, Allison; Salcedo, D.; Cubison, Michael J.; Huffman, J.; DeCarlo, Peter; Ulbrich, Ingrid M.; Docherty, Kenneth S.; Sueper, D. T.; Kimmel, Joel; Worsnop, Douglas R.; Trimborn, Achim; Northway, Megan; Stone, Elizabeth A.; Schauer, James J.; Volkamer, Rainer M.; Fortner, Edward; de Foy, B.; Wang, Jian; Laskin, Alexander; Shutthanandan, V.; Zheng, Junsheng; Zhang, Renyi; Gaffney, Jeffrey S.; Marley, Nancy A.; Paredes-Miranda, Guadalupe L.; Arnott, W. P.; Molina, Luisa T.; Sosa, G.; Jimenez, Jose L.

    2009-09-11

    Submicron aerosol was analyzed during the MILAGRO field campaign in March 2006 at the T0 urban supersite in Mexico City with a High-Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS) and complementary instrumentation. Mass concentrations, diurnal cycles, and size distributions of inorganic and organic species are similar to results from the CENICA supersite in April 2003 with organic aerosol (OA) comprising about half of the fine PM mass. Positive Matrix Factorization (PMF) analysis of the high resolution OA spectra identifies three major components: chemically-reduced urban primary emissions (hydrocarbon-like OA, HOA), oxygenated OA (OOA, mostly secondary OA or SOA), and biomass burning OA (BBOA) that correlates with levoglucosan and acetonitrile. BBOA includes several very large plumes from regional fires and likely also some refuse burning.

  19. Source apportionment of PM{sub 10} and PM{sub 2.5} in a desert region in northern Chile

    Energy Technology Data Exchange (ETDEWEB)

    Jorquera, Héctor, E-mail: jorquera@ing.puc.cl; Barraza, Francisco

    2013-02-01

    Estimating contributions of anthropogenic sources to ambient particulate matter (PM) in desert regions is a challenging issue because wind erosion contributions are ubiquitous, significant and difficult to quantify by using source-oriented, dispersion models. A receptor modeling analysis has been applied to ambient PM{sub 10} and PM{sub 2.5} measured in an industrial zone ∼ 20 km SE of Antofagasta (23.63°S, 70.39°W), a midsize coastal city in northern Chile; the monitoring site is within a desert region that extends from northern Chile to southern Perú. Integrated 24-hour ambient samples of PM{sub 10} and PM{sub 2.5} were taken with Harvard Impactors; samples were analyzed by X Ray Fluorescence, ionic chromatography (NO{sub 3}{sup −} and SO{sub 4}{sup =}), atomic absorption (Na{sup +}, K{sup +}) and thermal optical transmission for elemental and organic carbon determination. Receptor modeling was carried out using Positive Matrix Factorization (US EPA Version 3.0); sources were identified by looking at specific tracers, tracer ratios, local winds and wind trajectories computed from NOAA's HYSPLIT model. For the PM{sub 2.5} fraction, six contributions were found — cement plant, 33.7 ± 1.3%; soil dust, 22.4 ± 1.6%; sulfates, 17.8 ± 1.7%; mineral stockpiles and brine plant, 12.4 ± 1.2%; Antofagasta, 8.5 ± 1.3% and copper smelter, 5.3 ± 0.8%. For the PM{sub 10} fraction five sources were identified — cement plant, 38.2 ± 1.5%; soil dust, 31.2 ± 2.3%; mineral stockpiles and brine plant, 12.7 ± 1.7%; copper smelter, 11.5 ± 1.6% and marine aerosol, 6.5 ± 2.4%. Therefore local sources contribute to ambient PM concentrations more than distant sources (Antofagasta, marine aerosol) do. Soil dust is enriched with deposition of marine aerosol and calcium, sulfates and heavy metals from surrounding industrial activities. The mean contribution of suspended soil dust to PM{sub 10} is 50 μg/m{sup 3} and the peak daily value is 104 μg/m{sup 3}. For the PM{sub 2.5} fraction, suspended soil dust contributes with an average of 9.3 μg/m{sup 3} and a peak daily value of 31.5 μg/m{sup 3}. - Highlights: ► Ambient PM{sub 10} and PM{sub 2.5} were measured in an industrial zone within an arid region in South America. ► Dry climate allows accumulation of heavy metals deposited on the ground. ► Soil dust becomes enriched with tracers of anthropogenic activities. ► Average suspended soil dust reaches 9 μg/m{sup 3} for PM{sub 2.5} and 50 μg/m{sup 3} for PM{sub 10}. ► Peak daily soil dust reaches 31.5 μg/m{sup 3} for PM{sub 2.5} and 104 μg/m{sup 3} for PM{sub 10}.

  20. Reactive oxygen species associated with water-soluble PM2.5 in the southeastern United States: spatiotemporal trends and source apportionment

    OpenAIRE

    Verma, V.; T. Fang; Guo, H; King, L.; Bates, J. T.; R. E. Peltier; Edgerton, E.; Russell, A.J.; Weber, R. J.

    2014-01-01

    We assess the potential of the water-soluble fraction of atmospheric fine aerosols in the southeastern US to generate reactive oxygen species (ROS) and identify major ROS-associated emission sources. ROS-generation potential of particles was quantified by the dithiothreitol (DTT) assay and involved analysis of fine particulate matter (PM) extracted from high-volume quartz filters (23 h integrated samples) collected at various sites in diff...

  1. Source Apportionment and Spatial Pattern Analysis of River Niulanjiang%牛栏江污染物源解析与空间差异性分析

    Institute of Scientific and Technical Information of China (English)

    李发荣; 李玉照; 刘永; 李晓铭; 郭怀成

    2013-01-01

    牛栏江-滇池补水是缓解滇池生态用水短缺的重要工程,对牛栏江流域主要污染源与空间差异性的识别分析,将有助于进一步改善牛栏江的水质.采用CFA(对应分析)对牛栏江流域污染源进行解析识别,结果表明流域内TN、NH3-N(氨氮)等污染物主要来源于嵩明县境内,TP、氟化物等污染物主要来源于寻甸县境内.在CFA分析的基础上,采用HCA(层次聚类分析)和SOM(自组织映射神经网络)对4个监测点、10种污染物指标进行分析,以识别空间分布的差异性和相似性,并且评价各指标的空间分布特征及监测点代表性.结果表明:4个监测点中,TP、氟化物、砷化物、Vph(挥发酚)在寻甸县境内的七星桥污染最严重;TN、NH3-N在牛栏江上游嵩明县境内的四营污染最重.结合流域污染负荷调查可知,寻甸县的磷负荷最大,占流域总负荷的58.73%,七星桥的TP污染贡献大于其他3个监测点,与七星桥TP污染最为严重相符合.该研究结果可为牛栏江流域实施进一步的分段治理提供决策支撑.

  2. Radiocarbon-derived source apportionment of fine carbonaceous aerosols before, during, and after the 2014 Asia-Pacific Economic Cooperation (APEC) summit in Beijing, China

    Science.gov (United States)

    Liu, Junwen; Mo, Yangzhi; Li, Jun; Liu, Di; Shen, Chengde; Ding, Ping; Jiang, Haoyu; Cheng, Zhineng; Zhang, Xiangyun; Tian, Chongguo; Chen, Yingjun; Zhang, Gan

    2016-04-01

    The Asia-Pacific Economic Cooperation (APEC) summit took place in Beijing, China, 5-11 November 2014, during which numerous measures were performed to control the air pollution, and consequently, the sky of Beijing was so clean that the public called it "APEC blue." The concentrations before, during, and after the APEC summit are 14.4 ± 6.81 µg C/m3, 6.66 ± 2.99 µg C/m3, and 32.3 ± 10.6 µg C/m3, respectively, for organic carbon (OC), and 2.27 ± 1.17 µg C/m3, 0.76 ± 0.52 µg C/m3, and 4.99 ± 1.74 µg C/m3, respectively, for elemental carbon (EC). We quantify the contributions of fossil and nonfossil sources to the OC and EC using radiocarbon. Results show that the contribution of nonfossil sources is 56 ± 1% (before APEC), 61 ± 1% (during APEC), and 48 ± 1% (after APEC), respectively, for OC, and 36 ± 4% (before APEC), 46 ± 1% (during APEC), and 33 ± 4% (after APEC), respectively, for EC. Comparing to the period before APEC, 70% and 60% of fossil EC and OC and 60% and 50% of nonfossil EC and OC are reduced, respectively, implying that the control on the nonfossil sources has considerable contribution to the good air quality in Beijing. Both EC and OC mass loadings during the APEC summit would have increased by 60% if the biomass-burning activities were not taken into account for control. In such a case, the atmospheric visibility would decrease 20% at least and the blue sky thereby would likely not have been visible during the summit.

  3. On the Apportionment of Administrative Governance Functions within Multi-Campus Universities and University Systems. Research & Occasional Paper Series: CSHE.16.13

    Science.gov (United States)

    King, C. Judson

    2013-01-01

    Most public universities in the United States are formed into systems, containing more than one university or campus. There are clear rationales for these systems, including overall planning and coordination, budgeting efficiency, and effectiveness of dealings with the state government. The distribution of internal governance functions between the…

  4. Spatial distribution and source apportionment of water pollution in different administrative zones of Wen-Rui-Tang (WRT) river watershed, China.

    Science.gov (United States)

    Yang, Liping; Mei, Kun; Liu, Xingmei; Wu, Laosheng; Zhang, Minghua; Xu, Jianming; Wang, Fan

    2013-08-01

    Water quality degradation in river systems has caused great concerns all over the world. Identifying the spatial distribution and sources of water pollutants is the very first step for efficient water quality management. A set of water samples collected bimonthly at 12 monitoring sites in 2009 and 2010 were analyzed to determine the spatial distribution of critical parameters and to apportion the sources of pollutants in Wen-Rui-Tang (WRT) river watershed, near the East China Sea. The 12 monitoring sites were divided into three administrative zones of urban, suburban, and rural zones considering differences in land use and population density. Multivariate statistical methods [one-way analysis of variance, principal component analysis (PCA), and absolute principal component score-multiple linear regression (APCS-MLR) methods] were used to investigate the spatial distribution of water quality and to apportion the pollution sources. Results showed that most water quality parameters had no significant difference between the urban and suburban zones, whereas these two zones showed worse water quality than the rural zone. Based on PCA and APCS-MLR analysis, urban domestic sewage and commercial/service pollution, suburban domestic sewage along with fluorine point source pollution, and agricultural nonpoint source pollution with rural domestic sewage pollution were identified to the main pollution sources in urban, suburban, and rural zones, respectively. Understanding the water pollution characteristics of different administrative zones could put insights into effective water management policy-making especially in the area across various administrative zones. PMID:23404042

  5. Source apportionment of PM2.5 in Cork Harbour, Ireland using a combination of single particle mass spectrometry and quantitative semi-continuous measurements

    OpenAIRE

    Healy, Robert M.; Hellebust, Stig; Kourtchev, Ivan; Allanic, Arnaud; O'Connor, Ian P.; Bell, Jenny M.; Healy, David A.; Sodeau, John R.; Wenger, John C.

    2010-01-01

    An aerosol time-of-flight mass spectrometer (ATOFMS) was deployed for the measurement of the size resolved chemical composition of single particles at a site in Cork Harbour, Ireland for three weeks in August 2008. The ATOFMS was co-located with a suite of semi-continuous instrumentation for the measurement of particle number, elemental carbon (EC), organic carbon (OC), sulfate and particulate matter smaller than 2.5 μm in diameter (PM2.5). The temporality of the ambient ATOFMS particle class...

  6. Development of the EEG apportionment and the EEG differential costs through 2020; Die Entwicklung der EEG-Umlage und der EEG-Differenzkosten bis 2020

    Energy Technology Data Exchange (ETDEWEB)

    Kroll, Annette [Electrabel - GDF SUEZ S.A., Brussels (Belgium); Langrock, Thomas [GDF SUEZ Energie Deutschland AG, Berlin (Germany)

    2011-12-15

    Denial on the one hand and worst case scenarios on the other hand make it difficult for the observer to achieve a rational assessment of current energy policy, especially when it comes to the promotion of renewable energy sources and the German Renewables Act (EEG). This contribution attempts to help: It focuses on the direct cost of the EEG funding system. The scenarios are based on the National Renewable Energy Action Plan and the newly decided package of actions to help along the intended energy turnaround.

  7. Atmospheric occurrence, homologue patterns and source apportionment of short- and medium-chain chlorinated paraffins in Shanghai, China: Biomonitoring with Masson pine (Pinus massoniana L.) needles.

    Science.gov (United States)

    Wang, Xue-Tong; Zhou, Jun; Lei, Bing-Li; Zhou, Jing-Ming; Xu, Si-Yue; Hu, Bao-Ping; Wang, De-Qing; Zhang, Dong-Ping; Wu, Ming-Hong

    2016-08-01

    A comprehensive survey was conducted to Masson pine (Pinus massoniana L.) needles widely distributed in Shanghai in order to investigate the levels and homologue group patterns of short- and medium-chain chlorinated paraffins (SCCPs and MCCPs), to identify and quantitatively assess source contributions to the total CPs in pine needle samples. The concentration ranged from not detected (ND) to 13,600ngg(-1) with a geometric mean (GM) value of 63.7ngg(-1) for ΣSCCPs, from 12.4 to 33,500ngg(-1) with a GM value of 677ngg(-1) for ΣMCCPs, and from 14.0 to 45,700ngg(-1) with a GM value of 768ngg(-1) for total CPs. For different sampling units, the pollution levels both for SCCPs and MCCPs in pine needles were in the same orders: Pudong>suburbs>Puxi>Chongming. These significant differences in SCCPs and MCCPs among four sampling units could be associated with difference in industrial activities and to some extent also in population density. All pine needle samples (n=131) were divided into 2 groups by hierarchical cluster analysis (HCA) for SCCPs and MCCPs, the most abundant homologue groups in the bulk of pine needle samples were C11Cl5-7 and C13Cl5-7 for SCCPs, and C14Cl7-8 and C15Cl7-8 for MCCPs. Correlation analysis suggested that SCCPs and MCCPs in pine needles in the studied area may be derived from different sources. Four sources for pine needles were identified by the FA-MLR model; their relative contributions to the total CP burden in pine needles were 18.0% for F1 (attributed to commercial SCCP mixture), 42.2% for F2 (attributed to commercial MCCP mixture), 29.3% for F3 (attributed to LRAT), and 10.5% for F4 (unknown source). CP contamination of atmospheric air by point sources and long-range atmospheric transport in Shanghai should receive more attention by local government. PMID:27096489

  8. Saccharide Composition in Fine and Coarse Particulate Matter and Soils in Central Arizona and Use of Saccharides as Molecular Markers for Source Apportionment

    Science.gov (United States)

    Jia, Y.; Clements, A.; Fraser, M.

    2009-04-01

    The desert southwestern United States routinely exceeds health-based standards for coarse particulate matter [1]. PM10 concentrations are high in both urban and rural areas and are believed to originate from fugitive dust emissions from agricultural fields and roads and soil erosion from the surrounding desert locations. Soil together with its associated biota contains a complex mixture of biogenic detritus, including plant detritus, airborne microbes comprised of bacteria, viruses, spores of lichens and fungi, small algae, and protozoan cysts [4][5], which can mostly become airborne when winds are strong enough and soil dry enough to be re-entrained into the atmosphere [3]. Other potential sources to PM10 may include primary biological aerosol particles (PBAPs), given a multitude of flower, grass, and fungal species that thrive in the Sonoran desert and actively release pollens and spores throughout the year [2]. However, because soil and fugitive dust is also believed to contain a large number of these biological particles and is considered as a secondary host of PBAPs [3] [4], the role and contribution of PBAPs as a direct ambient PM source in the desert southwest have not been clearly stated or investigated. In an effort to identify and assess the relative contribution of these and other major PM sources in the southwestern US region, and particularly to assess the contribution from soil and fugitive dust, a series of ambient PM samples and soil samples were collected in Higley, AZ, USA, a suburb of the Phoenix metropolitan area which has seen rapid urban sprawl onto agricultural lands. Because of their suggested ability to track biologically important organic materials from natural environment [4][6][7][8][9][10], saccharides were chosen as the key compounds to trace the release of soil dusts into the atmosphere, and to elucidate other major sources that contribute to the PM levels in this location in the arid southwestern US. To this end, saccharide compounds were analyzed in size segregated soil and ambient PM samples at Higley; intra- and inter- comparisons were made between the ambient PM and three types of soil dust samples (agricultural soil, native soil, road dust) based on the particle size (fine vs. coarse), seasonality, and relative composition of 12 saccharide compounds. Based on the ambient concentrations of major saccharides and a number of other specific compounds (including elemental and organic carbon, ions, metals, alkanes, organic acids, and polycyclic aromatic hydrocarbons) that are simultaneously resolved in Higley PM samples, a Positive Matrix Factorization (PMF) model was performed to determine the key contributors to PM10 and PM2.5 levels. Six distinct factors were isolated, with two factors dominated by the enrichment of saccharide compounds. There was not consistency between the source profiles of these two saccharide rich source factors with the saccharide composition of the local size-segregated soil samples, which implies that there may be other major sources contributing to ambient PM saccharides. One possible alternative is that PBAPs that are injected directly into the atmosphere instead of residing in the surface soil and being re-entrained through soil erosion or agricultural processing. To our knowledge, this study is the first of its kind to compare the saccharide composition between the fine and coarse fraction of different soils types in two seasons, and to relate the contribution from soil dust to ambient PM using saccharide species. REFERENCE [1] AirData: Access to Air Pollution data. [cited 2009 Jan 11, 2009]; Available from: http://www.epa.gov/air/data/index.html [2] Allergy and Asthma in the Southwestern United States. [cited 2009 Jan 11, 2009]; Available from: http://allergy.peds.arizona.edu/southwest/swpollen.html [3] Cox, C.S., Wathes, C.M., 1995. Bioaerosols Handbook, Lewis Publishers, NY [4] Simoneit, B.R.T., Elias, V.O., et al., 2004. "Sugars - Dominant water-soluble organic compounds in soils and characterization as tracers in atmospheric particulate matter"

  9. A method for apportionment of natural and anthropogenic contributions to heavy metal loadings in the surface soils across large-scale regions.

    Science.gov (United States)

    Hu, Yuanan; Cheng, Hefa

    2016-07-01

    Quantification of the contributions from anthropogenic sources to soil heavy metal loadings on regional scales is challenging because of the heterogeneity of soil parent materials and high variability of anthropogenic inputs, especially for the species that are primarily of lithogenic origin. To this end, we developed a novel method for apportioning the contributions of natural and anthropogenic sources by combining sequential extraction and stochastic modeling, and applied it to investigate the heavy metal pollution in the surface soils of the Pearl River Delta (PRD) in southern China. On the average, 45-86% of Zn, Cu, Pb, and Cd were present in the acid soluble, reducible, and oxidizable fractions of the surface soils, while only 12-24% of Ni, Cr, and As were partitioned in these fractions. The anthropogenic contributions to the heavy metals in the non-residual fractions, even the ones dominated by natural sources, could be identified and quantified by conditional inference trees. Combination of sequential extraction, Kriging interpolation, and stochastic modeling reveals that approximately 10, 39, 6.2, 28, 7.1, 15, and 46% of the As, Cd, Cr, Cu, Ni, Pb, and Zn, respectively, in the surface soils of the PRD were contributed by anthropogenic sources. These results were in general agreements with those obtained through subtraction of regional soil metal background from total loadings, and the soil metal inputs through atmospheric deposition as well. In the non-residual fractions of the surface soils, the anthropogenic contributions to As, Cd, Cr, Cu, Ni, Pb, and Zn, were 48, 42, 50, 51, 49, 24, and 70%, respectively. PMID:27108044

  10. Application of CMB model for source apportionment of polycyclic aromatic hydrocarbons (PAHs) in coastal surface sediments from Rizhao offshore area, China.

    Science.gov (United States)

    Xue, Lidong; Lang, Yinhai; Liu, Aixia; Liu, Jie

    2010-04-01

    Polycyclic aromatic hydrocarbons (PAHs) in coastal surface sediments from Rizhao offshore area were analyzed by gas chromatography-mass spectrometry. A chemical mass balance (CMB) model developed by the U.S. Environmental Protection Agency (EPA), CMB8.2, was used to apportion sources of PAHs. Seven possible sources, including coal residential, coal power plant, diesel engines exhaust, gasoline engines exhaust, coke oven, diesel oil leaks, and wood burning, were chosen as the major contributors for PAHs in coastal surface sediments. To establish the fingerprints of the seven sources, source profiles were collected from literatures. After including degradation factors, the modified model results indicate that diesel oil leaks, diesel engines exhaust, and coal burning were the three major sources of PAHs. The source contributions estimated by the EPA's CMB8.2 model were 9.25%, 15.05%, and 75.70% for diesel oil leaks, diesel engines exhaust, and coal burning, respectively.

  11. Source Apportionment of Ambient PM10 in the Urban Area of Longyan City, China: a Comparative Study Based on Chemical Mass Balance Model and Factor Analysis Method

    Institute of Scientific and Technical Information of China (English)

    QIU Li-min; LIU Miao; WANG Ju; ZHANG Sheng-nan; FANG Chun-sheng

    2012-01-01

    In order to identify the day and night pollution sources of PM10 in ambient air in Longyan City,the authors analyzed the elemental composition of respirable particulate matters in the day and night ambient air samples and various pollution sources which were collected in January 2010 in Longyan with inductivity coupled plasma-mass spectrometry(ICP-MS).Then chemical mass balance(CMB)model and factor analysis(FA)method were applied to comparatively study the inorganic components in the sources and receptor samples.The results of factor analysis show that the major sources were road dust,waste incineration and mixed sources which contained automobile exhaust,soil dust/secondary dust and coal dust during the daytime in Longyan City,China.There are two major sources of pollution which are soil dust and mixture sources of automobile exhaust and secondary dust during the night in Longyan.The results of CMB show that the major sources are secondary dust,automobile exhaust and road dust during the daytime in Longyan.The major sources are secondary dust,soil dust and automobile exhaust during the night in Longyan.The results of the two methods are similar to each other and the results will guide us to plan to control the PM10 pollution sources in Longyan.

  12. Saccharide Composition in Fine and Coarse Particulate Matter and Soils in Central Arizona and Use of Saccharides as Molecular Markers for Source Apportionment

    Science.gov (United States)

    Jia, Y.; Clements, A.; Fraser, M.

    2009-04-01

    The desert southwestern United States routinely exceeds health-based standards for coarse particulate matter [1]. PM10 concentrations are high in both urban and rural areas and are believed to originate from fugitive dust emissions from agricultural fields and roads and soil erosion from the surrounding desert locations. Soil together with its associated biota contains a complex mixture of biogenic detritus, including plant detritus, airborne microbes comprised of bacteria, viruses, spores of lichens and fungi, small algae, and protozoan cysts [4][5], which can mostly become airborne when winds are strong enough and soil dry enough to be re-entrained into the atmosphere [3]. Other potential sources to PM10 may include primary biological aerosol particles (PBAPs), given a multitude of flower, grass, and fungal species that thrive in the Sonoran desert and actively release pollens and spores throughout the year [2]. However, because soil and fugitive dust is also believed to contain a large number of these biological particles and is considered as a secondary host of PBAPs [3] [4], the role and contribution of PBAPs as a direct ambient PM source in the desert southwest have not been clearly stated or investigated. In an effort to identify and assess the relative contribution of these and other major PM sources in the southwestern US region, and particularly to assess the contribution from soil and fugitive dust, a series of ambient PM samples and soil samples were collected in Higley, AZ, USA, a suburb of the Phoenix metropolitan area which has seen rapid urban sprawl onto agricultural lands. Because of their suggested ability to track biologically important organic materials from natural environment [4][6][7][8][9][10], saccharides were chosen as the key compounds to trace the release of soil dusts into the atmosphere, and to elucidate other major sources that contribute to the PM levels in this location in the arid southwestern US. To this end, saccharide compounds were analyzed in size segregated soil and ambient PM samples at Higley; intra- and inter- comparisons were made between the ambient PM and three types of soil dust samples (agricultural soil, native soil, road dust) based on the particle size (fine vs. coarse), seasonality, and relative composition of 12 saccharide compounds. Based on the ambient concentrations of major saccharides and a number of other specific compounds (including elemental and organic carbon, ions, metals, alkanes, organic acids, and polycyclic aromatic hydrocarbons) that are simultaneously resolved in Higley PM samples, a Positive Matrix Factorization (PMF) model was performed to determine the key contributors to PM10 and PM2.5 levels. Six distinct factors were isolated, with two factors dominated by the enrichment of saccharide compounds. There was not consistency between the source profiles of these two saccharide rich source factors with the saccharide composition of the local size-segregated soil samples, which implies that there may be other major sources contributing to ambient PM saccharides. One possible alternative is that PBAPs that are injected directly into the atmosphere instead of residing in the surface soil and being re-entrained through soil erosion or agricultural processing. To our knowledge, this study is the first of its kind to compare the saccharide composition between the fine and coarse fraction of different soils types in two seasons, and to relate the contribution from soil dust to ambient PM using saccharide species. REFERENCE [1] AirData: Access to Air Pollution data. [cited 2009 Jan 11, 2009]; Available from: http://www.epa.gov/air/data/index.html [2] Allergy and Asthma in the Southwestern United States. [cited 2009 Jan 11, 2009]; Available from: http://allergy.peds.arizona.edu/southwest/swpollen.html [3] Cox, C.S., Wathes, C.M., 1995. Bioaerosols Handbook, Lewis Publishers, NY [4] Simoneit, B.R.T., Elias, V.O., et al., 2004. "Sugars - Dominant water-soluble organic compounds in soils and characterization as tracers in atmospheric particulate matter", Environmental Science and Technology (38): 5939-5949. [5] Simoneit, B.R.T., Mazurek, M.A., 1981. "Air Pollution - the Organic-Components", Crc Critical Reviews in Environmental Control (11): 219-276. [6] Medeiros, P.M., Simoneit, B.R.T, 2007. "Analysis of sugars in environmental samples by gas chromatography-mass spectrometry", Jouranl of Chromatography A (1141): 271-278. [7] Rogge, W.F., Medeiros, P.M, et al., 2007. ‘Organic marker compounds in surface soils of crop fields from the San Joaquin Valley fugitive dust characterization study", Atmospheric Environment (41): 8183-8204. [8] Bauer, H., Claeys, M., et al., 2008. "Arabitol and mannitol as tracers for the quantification of airborne fungal spores", Atmospheric Environment (42): 588-593. [9] Elbert, W., Taylor, P.E., et al., 2007. "Contribution of fungi to primary biogenic aerosols in the atmosphere: wet and dry discharged spores, carbohydrates, and inorganic ions", Atmospheric Chemistry and Physics (7): 4569-4588. [10] Graham, B., Guyon, P., et al., 2003. "Organic compounds present in the natural Amazonian aerosol: Characterization by gas chromatography-mass spectrometry", Journal of Geophysical Research (108): 4766, doi:10.1029/2003JD003990.

  13. Characterization and source apportionment of aerosol light extinction with a coupled model of CMB-IMPROVE in Hangzhou, Yangtze River Delta of China

    Science.gov (United States)

    Wang, Jiao; Zhang, Yu-fen; Feng, Yin-chang; Zheng, Xian-jue; Jiao, Li; Hong, Sheng-mao; Shen, Jian-dong; Zhu, Tan; Ding, Jing; Zhang, Qi

    2016-09-01

    To investigate the characteristics and sources of aerosol light extinction in the Yangtze River Delta of China, a campaign was carried out in Hangzhou from December 2013 to November 2014. Hourly data for air pollutants including PM2.5, SO2, NO2, O3 and CO, and aerosol optical properties including aerosol scattering coefficient and aerosol absorbing coefficient was obtained in the environmental air quality automatic monitoring station. Meteorological parameters were measured synchronously in the automated meteorology monitoring station. Additionally, around seven sets of ambient PM2.5 samples per month were collected and analyzed during the campaign. The annual mean aerosol scattering coefficient, aerosol absorbing coefficient and aerosol single scattering albedo measured in this study was 514 ± 284 Mm- 1, 35 ± 20 Mm- 1 and 94% respectively. The aerosol extinction coefficient reconstructed using the modified IMPROVE (Interagency Monitoring of Protected Visual Environment) formula was compared to the measured extinction coefficient. Better correlations could be found between the measured and reconstructed extinction coefficient when RH was under 90%. A coupled model of CMB (chemical mass balance) and modified IMPROVE was used to apportion the sources of aerosol light extinction in Hangzhou. Vehicle exhaust, secondary nitrate and secondary sulfate were identified as the most significant sources for aerosol light extinction, accounted for 30.2%, 24.1% and 15.8% respectively.

  14. Development of a methodology examining the behaviours of VOCs source apportionment with micro-meteorology analysis in an urban and industrial area.

    Science.gov (United States)

    Xiang, Yang; Delbarre, Hervé; Sauvage, Stéphane; Léonardis, Thierry; Fourmentin, Marc; Augustin, Patrick; Locoge, Nadine

    2012-03-01

    During summer 2009, online measurements of 25 Volatile Organic Compounds (VOCs) from C6 to C10 as well as micro-meteorological parameters were simultaneously performed in the industrial city of Dunkerque. With the obtained data set, we developed a methodology to examine how the contributions of different source categories depend on atmospheric turbulences, and the results provided identification of emission modes. Eight factors were resolved by using Positive Matrix Factorization model and three of them were associated with mixed sources. The observed behaviours of contributions with turbulences lead to attribute some factors with sources at ground level, and some other factors with sources in the upper part of surface layer. The impact of vertical turbulence on the pollutant dispersion is also affected by the distance between sources and receptor site.

  15. SOURCE APPORTIONMENT OF PM2.5 IN SEATTLE, WA URBAN IMPROVE SITE: COMPARISON OF THREE RECEPTOR MODELS AND SOURCE PROFILES

    Science.gov (United States)

    IMPROVE protocol data were collected at the urban Beacon Hill monitoring site in Seattle, WA from 1996-99. The 289 sets of PM2.5 filters were analyzed for: metals using PIXIE and XRF, anions using ion chromatography, elemental hydrogen (H) by proton scattering, and elemental an...

  16. Characterization and source apportionment of atmospheric organic and elemental carbon during fall and winter of 2003 in Xi'an, China

    Directory of Open Access Journals (Sweden)

    J. J. Cao

    2005-06-01

    Full Text Available Continuous observation of atmospheric organic and elemental carbon (OC, EC were conducted at Xi'an during high pollution seasons from September 2003 to February 2004. PM2.5 samples were collected on pre-fired quartz-fiber filters with battery-powered mini-volume samplers every day and PM10 samples were collected every third days. Three types of source samples (i.e., coal-combustion, motor vehicle exhaust, and biomass burning were also collected during ambient sampling period. Ambient and source samples were analyzed for OC and EC by thermal/optical reflectance (TOR following the Interagency Monitoring of Protected Visual Environments (IMPROVE protocol. The average PM2.5 OC concentrations in fall and winter were 34.1±18.0 µg m-3 and 61.9±33.2 µg m-3, respectively, while EC were 11.3±6.9 µg m-3 and 12.3±5.3 µg m-3, respectively. Most of OC and EC were associated with fine particle (PM2.5 mode. The OC and EC levels at Xi'an are higher than most urban cities in Asia. The OC and EC in fall were found to be strongly correlated (R2>0.9, with moderate correlation in winter (R2=0.66. The carbonaceous aerosol accounted for 48.8±10.1% of the PM2.5 during fall and 45.9±7.5% during winter. Average OC/EC ratio was 3.3 in fall and 5.1 in winter with individual OC/EC ratios constantly exceeding 2.0. Elevated OC/EC ratios were found during heating seasons with increased coal combustion. The contribution of secondary organic carbon was not significant during winter. The time series of OC and EC showed periodic variability. Traffic contributes 5 and 7 day peaks in the spectrum, precipitation appears as a 10 day periodicity and biomass burning can be identified as a 24 day periodicity. Total carbon (TC was apportioned by absolute principal component analysis (APCA using the 8 carbon fraction data (OC1, OC2, OC3, OC4, EC1, EC2, EC3, and OP [a pyrolyzed carbon fraction]. TC attributes 73% to gasoline exhaust, 23% to diesel exhaust, and 4% to biomass burning during fall. However, TC attributes 44% each to gasoline exhaust and coal burning, 9% to biomass burning, and 3% to diesel exhaust during winter.

  17. Radiocarbon based source apportionment of black carbon in the form of PM10 elemental carbon aerosol particles at the Zeppelin Observatory, Svalbard

    Science.gov (United States)

    Winiger, Patrik; Andersson, August; Espen Yttri, Karl; Tunved, Peter; Gustafsson, Örjan

    2015-04-01

    Black carbon (BC) aerosol particles are formed from incomplete combustion of fossil fuel and biomass. Transported into the Arctic, they potentially contributes to climate warming. However, there are still large uncertainties related to the climate effects of BC, including aspects of radiative properties, mixing state of the particles, transport, atmospheric lifetime and sources. The current study aims to reduce source uncertainties by applying a top-down (observational) source-diagnostic isotope approach and comparing these to bottom-up (modeling) emission inventories to better constrain the source types and source regions. The use of natural abundance radiocarbon (Δ14C) is a powerful tool to distinguish between fossil (void of 14C) and biomass (contemporary 14C) combustion sources. Due to the well-defined end-members, 14C-measurements (alone) provide high precision (

  18. Source apportionment of mass concentration and inhalation risk with long-term ambient PCDD/Fs measurements in an urban area.

    Science.gov (United States)

    Ho, Chi-Chang; Chan, Chang-Chuan; Chio, Chia-Pin; Lai, Yi-Chieh; Chang-Chien, Guo-Ping; Chow, Judith C; Watson, John G; Chen, Lung-Wen A; Chen, Pau-Chung; Wu, Chang-Fu

    2016-11-01

    This study applies a receptor model to quantify source contributions to ambient concentration of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and inhalation cancer risk in Taipei from 2003 through 2009. Seventeen PCDD/F congeners were used in the effective variance solution to the Chemical Mass Balance equations to estimate source-specific mass contributions and inhalation risks. The average total PCDD/F concentration was 0.611pg/Nm(3) (0.036pg I-TEQ/Nm(3)). Traffic emissions contributed the most to the PCDD/F concentration (55.7%), followed by waste incinerators (18.6%) and joss stick burning (9.6%). For the inhalation cancer risk, the average was 1.1×10(-6) with traffic, waste incinerators, and joss paper burning as the main contributors (67.3%, 19.4%, and 6.3%, respectively). The mass and risk contributions of waste incinerators decreased significantly from 2003 to 2009 and were higher at downwind sites than at upwind sites. Reducing PCDD/F emissions from traffic and waste incinerators would provide the greatest health benefit. Policies that reduce the uncontrolled burning of joss stick and joss paper also need to be implemented. PMID:27267692

  19. Source apportionment for indoor PM2.5 and elemental concentrations using by a positive matrix factorization and an instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Airborne particulate matters, especially the PM2.5 (aerodynamic equivalent diameter, AED, less than 2.5 μm) fraction has been important. This is because of their potential for deposition on to the human respiratory system being accompanied by many harmful trace metals (such as As, Cd, Cr, Cu, Mn, Pb, Se, and Zn). The indoor air quality has become a great concern since late 1980s, because the population spends a majority of their time in various indoor environments. The indoor particulate matter may be influenced from outdoor environment and indoor sources such as environmental tobacco smoke (ETS), combustion devices, cooking, etc. In this study, we undertake the measurements of about 26 elements using instrumental neutron activation analysis (INAA). Based on our measurement data, we characterize concentration status and mutual relationship between indoor and adjacent outdoor air quality. Next, sources at indoor/outdoor environment were identified and the contributions of each source were quantified by positive matrix factorization (PMF)

  20. Source apportionment for indoor PM2.5 and elemental concentrations using by a positive matrix factorization and an instrumental neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Jong Myoung; Moon, Jong Hwa; Chung, Yong Sam [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Jung, Byoung Won; Lee, Jin Hong [Chungnam National University, Daejeon (Korea, Republic of)

    2009-05-15

    Airborne particulate matters, especially the PM2.5 (aerodynamic equivalent diameter, AED, less than 2.5 {mu}m) fraction has been important. This is because of their potential for deposition on to the human respiratory system being accompanied by many harmful trace metals (such as As, Cd, Cr, Cu, Mn, Pb, Se, and Zn). The indoor air quality has become a great concern since late 1980s, because the population spends a majority of their time in various indoor environments. The indoor particulate matter may be influenced from outdoor environment and indoor sources such as environmental tobacco smoke (ETS), combustion devices, cooking, etc. In this study, we undertake the measurements of about 26 elements using instrumental neutron activation analysis (INAA). Based on our measurement data, we characterize concentration status and mutual relationship between indoor and adjacent outdoor air quality. Next, sources at indoor/outdoor environment were identified and the contributions of each source were quantified by positive matrix factorization (PMF)

  1. Characterization and source apportionment of atmospheric organic and elemental carbon during fall and winter of 2003 in Xi'an, China

    OpenAIRE

    Cao, J. J.; J. C. Chow; Lee, S. C.; Y. Li; Chen, S. W.; An, Z. S.; Fung, K.; J. G. Watson; Zhu, C. S.; Liu, S X

    2005-01-01

    Continuous observation of atmospheric organic and elemental carbon (OC, EC) were conducted at Xi'an during high pollution seasons from September 2003 to February 2004. PM2.5 samples were collected on pre-fired quartz-fiber filters with battery-powered mini-volume samplers every day and PM10 samples were collected every third days. Three types of source samples (i.e., coal-combustion, motor vehicle exhaust, and biomass burning) were also colle...

  2. Calibration method for a photoacoustic system for real time source apportionment of light absorbing carbonaceous aerosol based on size distribution measurements

    Science.gov (United States)

    Utry, Noemi; Ajtai, Tibor; Pinter, Mate; Orvos, Peter I.; Szabo, Gabor; Bozoki, Zoltan

    2016-04-01

    In this study, we introduce a calibration method with which sources of light absorbing carbonaceous particulate matter (LAC) can be apportioned in real time based on multi wavelength optical absorption measurements with a photoacoustic system. The method is primary applicable in wintry urban conditions when LAC is dominated by traffic and biomass burning. The proposed method was successfully tested in a field campaign in the city center of Szeged, Hungary during winter time where the dominance of traffic and wood burning aerosol has been experimentally demonstrated earlier. With the help of the proposed calibration method a relationship between the measured Aerosol Angström Exponent (AAE) and the number size distribution can be deduced. Once the calibration curve is determined, the relative strength of the two pollution sources can be deduced in real time as long as the light absorbing fraction of PM is exclusively related to traffic and wood burning. This assumption is indirectly confirmed in the presented measurement campaign by the fact that the measured size distribution is composed of two unimodal size distributions identified to correspond to traffic and wood burning aerosols. The proposed method offers the possibility of replacing laborious chemical analysis with simple in-situ measurement of aerosol size distribution data.

  3. Source apportionment vs. emission inventories of non-methane hydrocarbons (NMHC) in an urban area of the Middle East: local and global perspectives

    Science.gov (United States)

    Salameh, Thérèse; Sauvage, Stéphane; Afif, Charbel; Borbon, Agnès; Locoge, Nadine

    2016-03-01

    We applied the positive matrix factorization model to two large data sets collected during two intensive measurement campaigns (summer 2011 and winter 2012) at a sub-urban site in Beirut, Lebanon, in order to identify NMHC (non-methane hydrocarbons) sources and quantify their contribution to ambient levels. Six factors were identified in winter and five factors in summer. PMF-resolved source profiles were consistent with source profiles established by near-field measurements. The major sources were traffic-related emissions (combustion and gasoline evaporation) in winter and in summer accounting for 51 and 74 wt %, respectively, in agreement with the national emission inventory. The gasoline evaporation related to traffic source had a significant contribution regardless of the season (22 wt % in winter and 30 wt % in summer). The NMHC emissions from road transport are estimated from observations and PMF results, and compared to local and global emission inventories. The PMF analysis finds reasonable differences on emission rates, of 20-39 % higher than the national road transport inventory. However, global inventories (ACCMIP, EDGAR, MACCity) underestimate the emissions up to a factor of 10 for the transportation sector. When combining emission inventory to our results, there is strong evidence that control measures in Lebanon should be targeted on mitigating the NMHC emissions from the traffic-related sources. From a global perspective, an assessment of VOC (volatile organic compounds) anthropogenic emission inventories for the Middle East region as a whole seems necessary as these emissions could be much higher than expected at least from the road transport sector.

  4. Limitation of the Use of the Absorption Angstrom Exponent for Source Apportionment of Equivalent Black Carbon: a Case Study from the North West Indo-Gangetic Plain.

    Science.gov (United States)

    Garg, Saryu; Chandra, Boggarapu Praphulla; Sinha, Vinayak; Sarda-Esteve, Roland; Gros, Valerie; Sinha, Baerbel

    2016-01-19

    Angstrom exponent measurements of equivalent black carbon (BCeq) have recently been introduced as a novel tool to apportion the contribution of biomass burning sources to the BCeq mass. The BCeq is the mass of ideal BC with defined optical properties that, upon deposition on the aethalometer filter tape, would cause equal optical attenuation of light to the actual PM2.5 aerosol deposited. The BCeq mass hence is identical to the mass of the total light-absorbing carbon deposited on the filter tape. Here, we use simultaneously collected data from a seven-wavelength aethalometer and a high-sensitivity proton-transfer reaction mass spectrometer installed at a suburban site in Mohali (Punjab), India, to identify a number of biomass combustion plumes. The identified types of biomass combustion include paddy- and wheat-residue burning, leaf litter, and garbage burning. Traffic plumes were selected for comparison. We find that the combustion efficiency, rather than the fuel used, determines αabs, and consequently, the αabs can be ∼1 for flaming biomass combustion and >1 for older vehicles that operate with poorly optimized engines. Thus, the absorption angstrom exponent is not representative of the fuel used and, therefore, cannot be used as a generic tracer to constrain source contributions.

  5. Application of positive matrix factorization to on-road measurements for source apportionment of diesel- and gasoline-powered vehicle emissions in Mexico City

    Directory of Open Access Journals (Sweden)

    D. A. Thornhill

    2009-12-01

    Full Text Available The goal of this research is to quantify diesel- and gasoline-powered motor vehicle emissions within the Mexico City Metropolitan Area (MCMA using on-road measurements captured by a mobile laboratory combined with positive matrix factorization (PMF receptor modeling. During the MCMA-2006 ground-based component of the MILAGRO field campaign, the Aerodyne Mobile Laboratory (AML measured many gaseous and particulate pollutants, including carbon dioxide, carbon monoxide (CO, nitrogen oxides (NOx, benzene, toluene, alkylated aromatics, formaldehyde, acetaldehyde, acetone, ammonia, particle number, fine particulate mass (PM2.5, and black carbon (BC. These serve as inputs to the receptor model, which is able to resolve three factors corresponding to gasoline engine exhaust, diesel engine exhaust, and the urban background. Using the source profiles, we calculate fuel-based emission factors for each type of exhaust. The MCMA's gasoline-powered vehicles are considerably dirtier, on average, than those in the US with respect to CO and aldehydes. Its diesel-powered vehicles have similar emission factors of NOx and higher emission factors of aldehydes, particle number, and BC. In the fleet sampled during AML driving, gasoline-powered vehicles are responsible for 97% of mobile source emissions of CO, 22% of NOx, 95–97% of aromatics, 72–85% of carbonyls, 74% of ammonia, negligible amounts of particle number, 26% of PM2.5, and 2% of BC; diesel-powered vehicles account for the balance. Because the mobile lab spent 17% of its time waiting at stoplights, the results may overemphasize idling conditions, possibly resulting in an underestimate of NOx and overestimate of CO emissions. On the other hand, estimates of the inventory that do not correctly account for emissions during idling are likely to produce bias in the opposite direction. Nevertheless, the fuel-based inventory suggests that mobile source emissions of CO and NOx are overstated in the official inventory while emissions of VOCs may be understated. For NOx, the fuel-based inventory is lower for gasoline-powered vehicles but higher for diesel-powered ones compared to the official inventory.

  6. Morphology, chemical composition and nanostructure of single carbon-rich particles studied by transmission electron microscopy: source apportionment in workroom air of aluminium smelters.

    Science.gov (United States)

    Weinbruch, Stephan; Benker, Nathalie; Kandler, Konrad; Ebert, Martin; Ellingsen, Dag G; Berlinger, Balázs; Thomassen, Yngvar

    2016-02-01

    Sources of C-rich particles at work places in two aluminium smelters in Norway were studied by transmission electron microscopy and energy-dispersive X-ray microanalysis. Based on morphology, nanostructure and chemistry, three different types of C-rich particles are distinguished: (a) chain-like agglomerates (70-100% by number, relative to the sum of C-rich particles) consisting of primary particles with typical onion-shell structure of graphene layers, (b) multi-walled carbon nanotube particles (≈3%) and (c) spheres or agglomerates of amorphous C-rich particles (0-30%). Chain-like agglomerates are interpreted as diesel soot in accordance with literature data on primary particle diameter, chemical composition and nanostructure of primary particles. The source of the observed multi-walled carbon nanotubes is not known. The amorphous C-rich particles most likely consist of organic carbon species which cannot be characterized further by X-ray microanalysis. Unaltered graphitic electrode material was not found among the C-rich particles. The high fraction of diesel soot particles indicates that elemental carbon is generally suited as proxy for diesel soot in aluminium smelters. However, due to the presence of carbon nanotubes and amorphous C-rich particles, detailed characterization of sources of carbon-rich particles by electron microscopy is recommended for accurate assessment of adverse health effects. PMID:26637216

  7. Source apportionment of atmospheric PM10 in Changchun by UNMIX%应用UNMIX模型解析长春市大气中PM10来源

    Institute of Scientific and Technical Information of China (English)

    王菊; 张悦悦; 金美英; 李翠玲; 房春生

    2014-01-01

    PM10is an important pollutant due to its adverse effects on visibility, climate change, and human health. To identify the regional pollution condition and develop effective control strategies to manage and maintain the urban air quality, it is important to study the pollution sources of PM10in the atmosphere. PM10 samples were collected at Jingyue Park, Labour Park, Clivia Park, sports academy, Children Park, bus hospital, business school and Post and Telecommunications College in Changchun during 2011 September to 2012 February using KC-120 PM10/TSP sampler (Application Research Institute of Laoshan Mountain in Qingdao) for the purpose to obtain the different source component and contributions of PM10. There are 40 samples were collected. After pretreatment, the samples of Be, V, Cr, Mn, Co, Ni, Cu, Zn, Mo, Ag, Cd, Sb, Ba, Tl, Pb, Na, Mg, K, Ca, a total of 19 kinds of inorganic elements were analyzed by ICP-MS. UNMIX method was used to qualitatively analyze the data that have standardized to study the sources of PM10in Changchun. Among them, Min Rsq=0.89 (89% of the data variance can be explained by the model), Min Sig/Noise=2.50. The result shows that there are three main sources of PM10 in Changchun : coal dust or industrial dust, vehicle exhaust or soil dust, the city’s comprehensive dust and other unknow dust source, the contribution rate were 19.5%, 13.1%, 67.4%, respectively. Correlation analysis was carried out on these 3 sources, the coefficient is not the theoretical value of 0, but from -0.553 to 0.345, source 1 and source 3 have the largest correlation was 0.553, followed by source 1 and source 2 for the 0.345. It shows that the PM10pollution in Changchun is the result of many factors. The predicted values of UNMIX were compared with the measured values and the result shows a linear positive correlationstatistically between the predicted values and the measured values with r2=0.98, and ther-Pearson is 0.713-0.980 for each species.%大气中可吸入颗粒物(PM10)是影响大气能见度、气候变化以及人体健康的重要污染物,研究大气中PM10的污染来源对于了解城市中大气的污染状况和制定大气污染物防治措施具有重要的意义。选择长春市的净月公园、劳动公园、君子兰公园、体育学院、儿童公园、客车医院、工商学院和邮电学院作为受体采样点,于2011年9月至2012年2月期间,采用KC-120型中流量PM10/TSP采样器(青岛崂山应用研究所)进行大气中可吸入颗粒物PM10的采样,共采集40个受体样品。样品经预处理后,采用电感耦合等离子体质谱法分析了样品中的Be、V、Cr、Mn、Co、Ni、Cu、Zn、Mo、Ag、Cd、Sb、Ba、Tl、Pb、Na、Mg、K、Ca共19种无机元素,将经过标准化后的760个数据代入EPA UNMIX6.0软件对长春市大气中PM10进行源解析研究,其中,Min Rsq=0.89(89%的数据方差可由该模型解释),Min Sig/Noise=2.50。结果表明:长春市大气中的PM10主要有3个来源:源1为燃煤尘或工业扬尘,贡献率为19.5%;源2为机动车尾气或土壤风沙尘,贡献率为13.1%,源3为城市综合扬尘和其他未知尘源,贡献率为67.4%。对这3个源进行相关性分析,3个源间的相关系数并不是理论值0,而是在-0.553~0.345间变化;源1和源3间相关性最大,相关系数为0.553;其次是源1与源2,为0.345。由此说明,长春市的PM10污染是多种因素综合作用的结果。将 UNMIX 模型的解析值与测量值进行回归分析,发现总物种的解析值与测量值间具有良好的线性正相关关系(r2=0.98),每个物种的解析值与测量值间的相关系数为0.713~0.980,相关性强,二者拟合效果较好。

  8. Flood-event based metal distribution patterns in water as approach for source apportionment of pollution on catchment scale: Examples from the River Elbe

    Science.gov (United States)

    Baborowski, Martina; Einax, Jürgen W.

    2016-04-01

    With the implementation of European Water Frame Work Directive (EU-WFD), the pollution sources in the River Elbe were assessed by the River Basin Community Elbe (RBC Elbe). Contaminated old sediments played the most significant role for inorganic and organic pollution. In terms of further improvement of the water quality in the river system, a prioritization of the known pollution sources is necessary, with respect to the expected effect in the case of their remediation. This requires information on mobility of contaminated sediments. To create a tool that allows the assessment of pollution trends in the catchment area, event based flood investigations were carried out at a sampling site in the Middle Elbe. The investigations were based on a comparable, discharge related sampling strategy. Four campaigns were performed between 1995 and 2006. The majority of the investigated 16 elements (>80%) studied more intensively in 2006 reached its maximum concentration during the first five days of the event. Only the concentrations of B, Cl-, and U declined with increasing discharge during the flood. The aim of the study was to verify that each flood event is characterized by an internal structure of the water quality. This structure is formed by the appearance of maximum values of water quality parameters at different times during the event. It could be detected by descriptive and multivariate statistical methods. As a result, internal structure of the water quality during the flood was influenced primarily by the source of the metals in the catchment area and its distance from the sampling point. The transport of metals in dissolved, colloidal or particulate form and changes of their ratios during the flood were however, not decisive for the formation of the structure. Our results show that the comparison of the structures obtained from events in different years is indicative of the pollution trend in the catchment area. Exemplarily the trend of the metal pollution in the River Elbe will be discussed.

  9. Source apportionment of fine PM and sub-micron particle number concentrations at a regional background site in the western Mediterranean: a 2.5 yr study

    Science.gov (United States)

    Cusack, M.; Pérez, N.; Pey, J.; Alastuey, A.; Querol, X.

    2013-02-01

    The chemical composition and sources of ambient fine particulate matter (PM1) over a period of 2.5 yr for a regional background site in the western Mediterranean are presented in this work. Major components (such as SO12-, NO3-, NH4+, organic and elemental carbon) and trace elements were analysed and the emission sources affecting PM1 were determined using Positive Matrix Factorisation (PMF). Furthermore, sub-micron particle number concentrations and the sources of these particles are also presented. Sources of sub-micron particles were determined by Principal Component Analysis (PCA). The mean PM1 concentration for the measurement period was 8.9 μg m-3, with organic matter (OM) and sulphate comprising most of the mass (3.2 and 1.5 μg m-3). A clear seasonal variation was recorded with higher PM1 concentrations in summer (11.2 μg m-3) compared to winter (6.6 μg m-3). This summer increase was due to elevated levels of sulphate and OM. Six sources were identified by PMF: secondary organic aerosol, secondary nitrate, industrial, traffic + biomass burning, fuel oil combustion and secondary sulphate. The daily variations of these sources were also determined, whereby the typically anthropogenic sources displayed elevated concentrations during the week with reductions at weekends. Nitrate levels were elevated in winter and negligible in summer, whereas secondary sulphate levels underwent a contrasting seasonal evolution with highest concentrations in summer, similar to the fuel oil combustion source. The SOA source was influenced by episodes of sustained pollution as a result of anticyclonic conditions occurring during winter, giving rise to thermal inversions and the accumulation of pollutants in the mixing layer. Increased levels in summer were owing to higher biogenic emissions and regional recirculation of air masses. The industrial source decreased in August due to decreased emissions during the vacation period. Increases in the traffic + biomass burning source were recorded in January, April and October, which were attributed to the occurrence of the aforementioned pollution episodes and local biomass burning emission sources, which include agriculture and domestic heating systems. Average particle number concentrations (N9-825 nm) from 5 November 2010 to 1 June 2011 and from 15 October 2011 to 18 December 2011 reached 3097 cm-3. Five emission sources of particles were identified by PCA; industrial + traffic + biomass burning, new particle formation + growth, secondary sulphate + fuel oil combustion, crustal material and secondary nitrate. Multilinear regression analysis was applied to the dataset to quantify the contribution of each source to the sub-micron particle number concentration. The new particle formation + growth source dominated the particle number concentration (56% of total particle number concentration), especially for particles 100 nm) and thus did not influence the particle number concentration significantly.

  10. Source apportionment of fine PM and sub-micron particle number concentrations at a regional background site in the western Mediterranean: a 2.5 year study

    Science.gov (United States)

    Cusack, M.; Pérez, N.; Pey, J.; Alastuey, A.; Querol, X.

    2013-05-01

    The chemical composition and sources of ambient fine particulate matter (PM1) over a period of 2.5 years for a regional background site in the western Mediterranean are presented in this work. Furthermore, sub-micron particle number concentrations and the sources of these particles are also presented. The mean PM1 concentration for the measurement period was 8.9 μg m-3, with organic matter (OM) and sulphate comprising most of the mass (3.2 and 1.5 μg m-3 respectively). Six sources were identified in PM1 by Positive Matrix Factorisation (PMF): secondary organic aerosol, secondary nitrate, industrial, traffic + biomass burning, fuel oil combustion and secondary sulphate. Typically anthropogenic sources displayed elevated concentrations during the week with reductions at weekends. Nitrate levels were elevated in winter and negligible in summer, whereas secondary sulphate levels underwent a contrasting seasonal evolution with highest concentrations in summer, similar to the fuel oil combustion source. The SOA source was influenced by episodes of sustained pollution as a result of anticyclonic conditions occurring during winter, giving rise to thermal inversions and the accumulation of pollutants in the mixing layer. Increased levels in summer were owing to higher biogenic emissions and regional recirculation of air masses. The industrial source decreased in August due to decreased emissions during the vacation period. Increases in the traffic + biomass burning source were recorded in January, April and October, which were attributed to the occurrence of the aforementioned pollution episodes and local biomass burning emission sources, which include agriculture and domestic heating systems. Average particle number concentrations (N9-825 nm) from 5/11/2010 to 01/06/2011 and from 15/10/2011 to 18/12/2011 reached 3097 cm-3. Five emission sources of particle of sub-micron particles were determined by Principal Component Analysis (PCA); industrial + traffic + biomass burning, new particle formation + growth, secondary sulphate + fuel oil combustion, crustal material and secondary nitrate. The new particle formation + growth source dominated the particle number concentration (56% of total particle number concentration), especially for particles 100 nm) and thus did not influence the particle number concentration significantly.

  11. Source apportionment of Beijing air pollution during a severe winter haze event and associated pro-inflammatory responses in lung epithelial cells

    Science.gov (United States)

    Liu, Qingyang; Baumgartner, Jill; Zhang, Yuanxun; Schauer, James J.

    2016-02-01

    Air pollution is a leading risk factor for the disease burden in China and globally. Few epidemiologic studies have characterized the particulate matter (PM) components and sources that are most responsible for adverse health outcomes, particularly in developing countries. In January 2013, a severe haze event occurred over 25 days in urban Beijing, China. Ambient fine particulate matter (PM2.5) was collected at a central urban site in Beijing from January 16-31, 2013. We analyzed the samples for water soluble ions, metals, elemental carbon (EC), organic carbon (OC), and individual organic molecular markers including n-alkanes, hopanes, PAHs and sterols. Chemical components were used to quantify the source contributions to PM2.5 using the chemical mass balance (CMB) model by the conversion of the OC estimates combined with inorganic secondary components (e.g. NH4+, SO42-, NO3-). Water extracts of PM were exposed to lung epithelial cells, and supernatants recovered from cell cultures were assayed for the pro-inflammatory cytokines by a quantitative ELLSA method. Linear regression models were used to estimate the associations between PM sources and components with pro-inflammatory responses in lung epithelial cells following 24-hrs and 48-hrs of exposure. The largest contributors to PM2.5 during the monitoring period were inorganic secondary ions (53.2% and 54.0% on haze and non-haze days, respectively). Other organic matter (OM) contributed to a larger proportion of PM2.5 during haze days (16.9%) compared with non-haze days (12.9%), and coal combustion accounted for 10.9% and 8.7% on haze and non-haze days, respectively. We found PM2.5 mass and specific sources (e.g. coal combustion, traffic emission, dust, other OM, and inorganic secondary ions) were highly associated with inflammatory responses of lung epithelial cells. Our results showed greater responses in the exposure to 48-hr PM2.5 mass and its sources compared to 24-hr PM exposure, and that secondary and coal combustion sources play an important role in short-term inflammation and require cost-effective policy to control their contributions to air pollution.

  12. Application of positive matrix factorization to on-road measurements for source apportionment of diesel- and gasoline-powered vehicle emissions in Mexico City

    Science.gov (United States)

    Thornhill, D. A.; Williams, A. E.; Onasch, T. B.; Wood, E.; Herndon, S. C.; Kolb, C. E.; Knighton, W. B.; Zavala, M.; Molina, L. T.; Marr, L. C.

    2010-04-01

    The goal of this research is to quantify diesel- and gasoline-powered motor vehicle emissions within the Mexico City Metropolitan Area (MCMA) using on-road measurements captured by a mobile laboratory combined with positive matrix factorization (PMF) receptor modeling. During the MCMA-2006 ground-based component of the MILAGRO field campaign, the Aerodyne Mobile Laboratory (AML) measured many gaseous and particulate pollutants, including carbon dioxide, carbon monoxide (CO), nitrogen oxides (NOx), benzene, toluene, alkylated aromatics, formaldehyde, acetaldehyde, acetone, ammonia, particle number, fine particulate mass (PM2.5), and black carbon (BC). These serve as inputs to the receptor model, which is able to resolve three factors corresponding to gasoline engine exhaust, diesel engine exhaust, and the urban background. Using the source profiles, we calculate fuel-based emission factors for each type of exhaust. The MCMA's gasoline-powered vehicles are considerably dirtier, on average, than those in the US with respect to CO and aldehydes. Its diesel-powered vehicles have similar emission factors of NOx and higher emission factors of aldehydes, particle number, and BC. In the fleet sampled during AML driving, gasoline-powered vehicles are found to be responsible for 97% of total vehicular emissions of CO, 22% of NOx, 95-97% of each aromatic species, 72-85% of each carbonyl species, 74% of ammonia, negligible amounts of particle number, 26% of PM2.5, and 2% of BC; diesel-powered vehicles account for the balance. Because the mobile lab spent 17% of its time waiting at stoplights, the results may overemphasize idling conditions, possibly resulting in an underestimate of NOx and overestimate of CO emissions. On the other hand, estimates of the inventory that do not correctly account for emissions during idling are likely to produce bias in the opposite direction.The resulting fuel-based estimates of emissions are lower than in the official inventory for CO and NOx and higher for VOCs. For NOx, the fuel-based estimates are lower for gasoline-powered vehicles but higher for diesel-powered ones compared to the official inventory. While conclusions regarding the inventory should be interpreted with care because of the small sample size, 3.5 h of driving, the discrepancies with the official inventory agree with those reported in other studies.

  13. Mathematical aspects of degressive proportionality

    CERN Document Server

    Slomczynski, Wojciech

    2011-01-01

    We analyze properties of apportionment functions in context of the problem of allocating seats in the European Parliament. Necessary and sufficient conditions for apportionment functions are investigated. Some exemplary families of apportionment functions are specified and the corresponding partitions of the seats in the European Parliament among the Member States of the European Union are presented. Although the choice of the allocation functions is theoretically unlimited, we show that the constraints are so strong that the acceptable functions lead to rather similar solutions.

  14. Delphi Interface Maintenance System

    Data.gov (United States)

    Department of Transportation — DIMS is the primary financial information system for tracking federally funded highway projects. It tracks authorizations, obligations, apportionments, allocations,...

  15. A New Source Apportionment Method of Maxed Dust Source Based on Cluster Analysis and Factor Analysis%基于聚类分析和因子分析的混合尘源解析新方法

    Institute of Scientific and Technical Information of China (English)

    郑雪峰; 邹长武; 印红玲

    2011-01-01

    The cluster analysis and factor analysis methods were successfully used to solve the problem of multicollinearity in CMB ( chemical mass balance)model. First the cluster analysis was used to analyse the colinearity among the emission sources, then the main factors of the emission sources with strong colinearity were selected by principal component analysis. Bring them and other single sources into the CMB to calculate.Finally returned the main factors contribution to single source of mixed dust sources, the contribution of each emission sources could be acquired.Compared with the other methods,the results showed that the analytical results were realistic and the method was feasible.%运用聚类分析扣因子分析来解决大气颗粒物源解析CMB模型(化学质量平衡模型)在解析混合尘源中遇到的共线性问题.即通过聚类分析对排放源进行共线性强弱分类,根据分析结果对其中共线性较强的一类(扬尘类源)提取主因子,并和其他独立尘源共同带入CMB模型进行计算.最后将主因子贡献量返回,得到各个源贡献值.通过和其他方法的效果进行比较,结果表明,该方法解析结果符合实际,具有可行性.

  16. 南四湖流域种植业面源污染氮磷源解析研究%Source Apportionment of Nitrogen and Phosphorus from Cropping Non-point Source Pollution in Nansi Lake Basin

    Institute of Scientific and Technical Information of China (English)

    刘静; 路凤; 杨延钊; 徐娜; 王田妮

    2012-01-01

    利用田间径流池采集南四湖流域种植业农田地表径流样品,分析其不同形态的氮磷数据,汇总数据得到南四湖流域种植业的氮磷源成分谱;并在南四湖区11条主要入湖河流入湖口处采集水样,测定氮磷含量,利用主成分分析法对南四湖流域种植业面源污染氮磷来源进行了源解析.结果表明,南四湖流域氮磷种植业面源污染来源有3种,3个主成分累积方差贡献率为95.275%.第一类污染途径为降雨淋溶小麦-玉米轮作农田产生的地表径流对河流产生的污染,这种污染的范围广且贡献率较大为50.220%;第二类污染途径为降雨淋溶大蒜-玉米轮作农田产生的地表径流流入南四湖入湖河流引起的,影响面也较广,贡献率为25.119%;第三类污染途径为自然降雨时,小麦-水稻轮作农田产生的地表径流对河流的污染,贡献率为19.937%.%Field runoff pools were used to collect the field surface runoff samples of different cropping systems in Nansi Lake region,and different forms of nitrogen(N) and phosphorus(P) data were analyzed.The source profiles of N and P in different cropping systems were also obtained by summarizing the experimental data measured in the current study.Samples were also collected from the 11 main rivers of Nansi Lake basin and the concentrations of N and P were determined.Principle component analysis(PCA) was applied to obtain cropping non-point pollution sources of N and P.The result showed that three types of N and P contamination sources were apportioned in Nansi Lake basin,explaining 95.275% of the total variance.The first source was from field surface runoff of wheat-maize rotation with a wide pollution range and a larger contribution,and it contributed 50.220% of the total contamination burden;the second type of N and P source was the water runoff pollution from garlic-maize rotation,were 25.119% contribution;the third source was the surface runoff from wheat-rice rotation,and it contributed 19.937%.

  17. 南京市典型工业区耕地中多环芳烃源解析%SOURCE APPORTIONMENT OF POLYCYCLIC AROMATIC HYDROCARBONS IN AGRICULTURAL SOIL IN TYPICAL INDUSTRIAL ZONE IN NANJING CITY

    Institute of Scientific and Technical Information of China (English)

    葛成军; 俞花美

    2009-01-01

    多环芳烃作为重要的环境激素类物质,对环境和人类健康具有严重危害而受到人们的广泛重视.选择南京市某一大型钢铁集团周边耕地土壤为研究对象,对研究区域内多环芳烃(PAHs)残留量进行调查.并对其污染来源进行解析,为该区域土壤PAHs的综合防治提供参考依据.结果表明:PAHs总残留量范围为312.2~27 580.9ng/g,且以4环以上多环芳烃组分为主.单一污染物以芘、屈、荧蒽、苯并[a]芘、葸、菲、苯并[a]蒽、苯并[k]荧蒽、茚并[1,2,3-cd]芘、苯并[g,h,i]苝为主.不同样区土壤PAHs残留量受常年风向影响明显.推测工业区的气体性排放物是本研究区域土壤中PAHs的主要来源.大气沉降可能是导致本研究区PAHs污染的重要途径之一.另外,地表径流、固体废弃物排放、生活燃煤等导致部分采样点含量较高.在对下风向区域中距中心污染源不同距离采样点PAHs含量分析时发现,高环PAHs总量总体表现出随污染源距离的增加,污染程度递减的规律.在对多环芳烃源成分谱轮廓特征的分析基础上,利用各种参数,从分子量优势度、环数相对丰度、特征指数等方面,分别对各区域土壤中多环芳烃来源进行比较分析,据此推断,四区域:PAHs污染均在不同程度上受化石的燃烧所致,但各区域的PAHs污染源不同.钢铁企业内的炼焦厂是该区域多环芳烃主要污染源之一.

  18. 浅议作业成本法在环境成本计算和分摊中的应用%Analysis of activity cost method used in calculation and apportionment of environmental cost

    Institute of Scientific and Technical Information of China (English)

    李琼

    2013-01-01

    在目前传统会计系统下,环境成本直接计算分摊到制造费用,然后由所有产品共同分摊环境成本,造成产品成本信息扭曲。针对这一问题,采用作业成本法,可以通过设置作业成本库,并通过成本动因科学地、合理地确定计量环境成本,从而有效地解决这个问题,有利于管理层利用正确的产品成本信息做出有利于环境效应并具有长远发展能力的产品的决策。%Under current traditional accounting system,environmental cost is directly apportioned to manufacturing cost to be shared by all products thus generating twisted product cost information. To cope with this,activity cost method is employed. It establishes an activity cost pool and then scales environmental cost scientifically and reasonably based on cost drivers. This approach is helpful to decision making by management with correct product cost information,which favors development of a more environment-friendly and lasting product.

  19. 污灌湿地六六六和滴滴涕残留现状及源分析%Pollution characterization and source apportionment of HCH and DDT in sewage irrigation soil of Xiao Qing River wetland

    Institute of Scientific and Technical Information of China (English)

    吕晓磊; 王立; 马放; 刘丽艳; 李一凡

    2012-01-01

    为考察小清河污灌湿地中滴滴涕(Dichlorodiphenyltrichloroethane,DDT)和六六六(Hexachlorocyclohexane,HCH)的残留量及污染来源,并研究污染物(DDT和HCH)沿土壤垂直剖面的分布规律,对不同污灌区土壤样品进行索氏萃取、硅胶净化等预处理后,用气质联用仪测定HCH和DDT的质量浓度.结果表明:湿地表层土壤中HCH和DDT平均质量分数分别为0.042和0.204μg/kg,质量分数范围分别为ND~0.225μg/kg和ND~1.204μg/kg,远低于国家土壤环境质量标准(GB15618—1995)中规定的土壤DDT和HCH残留量一级标准限值0.05 mg/kg,处于较低的残留水平;无污灌湿地HCH异构体残留量依次为β-HCH〉α-HCH〉γ-HCH,HCH残留主要是历史使用的农药残留和少量新成污染;湿地DDT污染主要以DDE形式存在,是历史使用的农药残留造成的;污灌降低了土壤中DDT和HCH的残留量,平均降低比率为67.16%和78%;湿地土壤相同样点中DDT残留量高于HCH残留量;DDT残留量随土壤深度的增加整体呈现减少的趋势,HCH残留质量分数随土壤深度变化无明显规律.%To investigate the residues and pollution sources of DDT and HCH in the Xiao Qing River sewage irrigated wetland and study the distribution of pollutants(DDT and HCH) along the vertical soil profile,soil samples were pretreated by Soxhlet extraction and silica gel purification,and the HCH and DDT content were analyzed by GC-MS.The results show that the concentrations of ΣHCHs and ΣDDTs in the soils range from ND-0.225 μg/kg and ND-1.204 μg/kg respectively,with the mean concentrations of 0.042 μg/kg and 0.204 μg/kg.The concentrations of DDTs and HCHs are below the national soil environmental quality standards(GB 15618—1995),which are at a low residue levels.The HCH residues in wetlands without irrigation are caused mainly by historical pesticide using and there is few pollutions generated recently.DDT contamination of wetlands exists mainly in the form of DDE,that is due to historical pesticide using.Sewage irrigation reduced soil residues of DDT and HCH,with average reduction rate of 67.16% and 78%.The HCH residues are higher than DDT residues at the same point.The DDT contents drop sharply along the soil profiles,and the HCH contents change irregularly along the soil profiles.

  20. Air pollution source apportionment before, during, and after the 2008 Beijing Olympics and association of sources to aldehydes and biomarkers of blood coagulation, pulmonary and systemic inflammation, and oxidative stress in healthy young adults

    Science.gov (United States)

    Altemose, Brent A.

    Based on principal component analysis (PCA) of air pollution data collected during the Summer Olympic Games held in Beijing, China during 2008, the five source types of air pollution identified -- natural soil/road dust, vehicle and industrial combustion, vegetative burning, oil combustion, and secondary formation, were all distinctly lower during the Olympics. This was particularly true for vehicle and industrial combustion and oil combustion, and during the main games period between the opening and closing ceremonies. The reduction in secondary formation was reflective of a reduction in nitrogen oxides, but this also contributed to increased ozone concentrations during the Olympic period. Among three toxic aldehydes measured in Beijing during the same time period, only acetaldehyde had a reduction in mean concentration during the Olympic air pollution control period compared to the pre-Olympic period. Accordingly, acetaldehyde was significantly correlated with primary emission sources including vegetative burning and oil combustion, and with several pollutants emitted mainly from primary sources. In contrast, formaldehyde and acrolein increased during the Olympic air pollution control period; accordingly both were significantly correlated with ozone and with the secondary formation source type. These findings indicate primary sources may dominate for acetaldehyde while secondary sources may dominate for formaldehyde and acrolein. Biomarkers for pulmonary inflammation (exhaled breath condensate (EBC) pH, exhaled nitric oxide, and EBC nitrite) and hemostasis and blood coagulation (vWF and sCD62p) were most consistently associated with vehicle and industrial combustion, oil combustion, and vegetative burning. The systemic inflammation biomarker 8-OHdG was most consistently associated with vehicle and industrial combustion. In contrast, the associations between the biomarkers and the aldehydes were generally not significant or in the hypothesized direction, although EBC nitrite was associated with both acrolein and acetaldehyde, and sCD62p was associated with acetaldehyde. Notably, the biomarker sCD40L showed few significant associations with any of the air pollution source types or aldehydes. The findings indicate that implementing controls for combustion sources may have a positive impact on cardiorespiratory health, even in healthy young adults. More aggressive control of vegetative burning and further reduction of nitrogen oxide concentrations would likely have an even more positive impact.

  1. Characteristics and sources apportionment of PM25-bound PAHs in Kunming%昆明城区大气PM2.5中PAHs的污染特征及来源分析

    Institute of Scientific and Technical Information of China (English)

    毕丽玫; 郝吉明; 宁平; 史建武; 施择; 徐晓峰

    2015-01-01

    A set of PM2.5 samples from three sampling sites belonging to the regional air monitoring networks of Kunming were collected during April 2013 to January 2014, and 16selected PAHs were analyzed by GC-MS. Average concentrations of PM2.5-bound PAHs from the industrial area (Jinding Mountain), traffic area (Dongfeng Tung Road) and clean area (Xishan Forest Park) were 40.67, 22.64, 22.07ng/m3. High atmospheric pressure and the input of air mass originated from the Qujing area were the cause of rising PAHs concentration in Kunming. Result of health risk assessment of PAHs showed, the concentration of BaPeq at Jinding Mountain, Dongfeng Tung Road and Xishan Forest Park was 6.28, 4.00, 2.94ng/m3, respectively, exceeded the national ambient air quality standard (2.5ng/m3) in China. The PAHs in industrial area and traffic area were mainly influenced by vehicle emission (50.80% and 40.20%), followed by coal combustion (35.55% and 39.23%), biomass combustion (7.30% and 7.98%); clean area was effected by vehicle emission (81.84%) and biomass combustion (9.73%).%2013年4月至2014年1月期间,在昆明城区3个采样点采集了大气细颗粒物(PM2.5)样品,利用气相色谱-质谱联用仪对PM2.5载带的16种PAHs进行定量分析.结果表明:工业区(金鼎山)、交通密集区(东风东路)、清洁对照点(西山森林公园)PM2.5上PAHs平均含量分别为40.67,22.64,22.07ng/m3.通过常规气象因素及气团后向轨迹模型分析发现,起源于曲靖地区的污染气团传输及昆明大气高压形成的下沉气流是导致昆明PAHs浓度上升的重要原因.金鼎山、东风东路、西山森林公园的BaPeq浓度分别为6.28,4.00,2.94ng/m3,均高于国家环境空气质量二级标准(2.5ng/m3).源解析结果显示,工业区(金鼎山)和交通密集区(东风东路)的 PAHs 污染来源一致,主要来自机动车排放,其贡献率分别为50.80%和40.20%,其次为燃煤排放,贡献率为35.55%和39.23%,再次为生物质燃烧,贡献率为7.30%和7.98%;作为清洁对照点的西山森林公园的 PAHs则来自汽车尾气排放(81.84%)和生物质燃烧排放(9.73%).

  2. 50 CFR 679.21 - Prohibited species bycatch management.

    Science.gov (United States)

    2010-10-01

    ... apportionment of a bycatch allowance on the following types of information: (A) Seasonal distribution of prohibited species; (B) Seasonal distribution of target groundfish species relative to prohibited species... section. (3) Allocations of the BS Chinook salmon PSC limits—(i) Seasonal apportionment. NMFS...

  3. Methods for Characterizing the Distribution of Exhaust Emissions from Light-Duty, Gasoline-Powered Motor Vehicles in the U.S. Fleet

    Science.gov (United States)

    Mobile sources significantly contribute to ambient concentrations of airborne particulate matter. Source apportionment studies for PMlO and PM2.5 indicate that mobile sources can be responsible for over half of the ambient PM measured in an urban area. Recent source apportionment...

  4. Inverse modeling to estimate local source contributions in a complex environment with nearby port, airport, highway, and industrial sources

    Science.gov (United States)

    Source apportionment is challenging in urban environments with clustered sourceemissions that have similar chemical signatures. A field and inverse modeling studywas conducted in Elizabeth, New Jersey to observe gaseous and particulate pollutionnear the Port of New York and New J...

  5. PARTICLE SPECIATION AND EMISSION PROFILES OF SMALL 2-STROKE ENGINES

    Science.gov (United States)

    The Human Exposure and Atmospheric Sciences Division (HEASD) conducts studies designed to acquire information from emission sources for use in source apportionment studies. The objective of this work is to characterize a complete, speciated emission profile (PM and air toxics) ...

  6. Legislative Districts - House Districts

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This layer represents the Arkansas State House of Representatives district boundaries adopted by the Arkansas Board of Apportionment on July 29, 2011. The Board of...

  7. ICP-MS法测定板蓝根颗粒中重金属及有害元素的含量并分析其来源%Determination and source apportionment of heavy metals and hazardous elements in Banlangen granules by ICP- MS

    Institute of Scientific and Technical Information of China (English)

    李春盈; 张玉英

    2012-01-01

    目的 测定板蓝根颗粒中砷、镉、汞、铅、铬、铜、锰、钼、镍、钯、铂、钒、锇、铑、钌、铱等重金属及有害元素的含量并探究其来源.方法 以密闭高压微波消解技术处理样品,采用电感耦合等离子体质谱法以全定量的方式测定As、Cd、Hg、Pb的含量,以半定量的方式测定其余12种重金属及有害元素的含量.结果 板蓝根颗粒中As、Cd、Hg和Pb的加样回收率为96.2%~109.5%,RSD低于2.6%,检出限为2.1 ×10-4 ~0.017μg·g-1.板蓝根颗粒中除砷含量较高外,其余15种元素含量均远低于限度值.通过测定板蓝根、制剂中间体及板蓝根颗粒中的砷含量,确定成品中的砷来源于板蓝根药材.结论 所用方法准确、灵敏、简便,适用于板蓝根颗粒中重金属及有害元素的含量分析.%OBJECTIVE To determine the contents of As, Cd, Hg, Pb, Cr, Cu, Mn, Mo, Ni, Pd, Pt, V, Os, Rb, Ru and Ir in Banlangen granules and analyze their source. METHODS A rapid method was established based on microwave digestion assisted with Inductively Coupled Plasma-Mass Spectrometer( ICP - MS) for full quantitative analysis for As,Cd,Hg or Pb.and semi quantitative analysis for other 12 elements. RESULTS The recovery of As,Cd,Hg and Pb in Banlangen granules was 96.2% - 109.5% ,with RSD lower than 2.6 %.The detection limit was in the range of 2. 1 ×l0-4 -0.017 μg·g-1. CONCLUSION The proposed method is accurate and rapid,and can be applied to the inspection of heavy metals and hazardous elements in Banlangen granules.

  8. Distribution Characteristics and Source Apportionment of Polycyclic Aromatic Hydrocarbons (PAHs) in the Liaohe River Drainage Basin,Northeast China.%辽河流域多环芳烃(PAHs)的分布特征及来源解析

    Institute of Scientific and Technical Information of China (English)

    张岩林; 胡健; 刘宝剑; 李思亮; 灌瑾

    2012-01-01

    Sixteen polycyclic aromatic hydrocarbons(PAHs) in surface water and suspended particulate matter(SPM) in the major rivers of the Liaohe River drainage basin were determined by GC/MS.The concentrations and distribution characteristics,pollution levels,and sources of PAHs were discussed.The total PAHs concentrations range from 0.41 to 76.45 μg·g-1(dry weight) in SPM,and 32.57 to 108.47 ng·L-1 in surface water,respectively.The PAHs concentrations in western Liaohe River are higher than those in eastern Liaohe River and its main streams.The compositions of PAHs are predominant by low-ring PAHs(including two-and three-ring PAHs),while the percentage of low-ring PAHs in dissolved form is higher than that in SPM.The two-ring PAHs percentage is highest with an average of 68.19 % in dissolved PAHs,while the three-ring PAHs percentage is highest with an average of 66.28% in SPM,respectively.Compared with other rivers both at home and abroad,the PAHs concentrations in the Liaohe River drainage basin are at a lower level,and some rivers have suffered PAHs contamination to a certain extent.The main sources of PAHs are petroleum and fossil fuel combustion-based mixture,which are related to the complex energy structure of Liaoning Province.%采用气相色谱-质谱(GC/MS)的分析方法,对辽河水系主要河流的表层水和悬浮物中的16种PAHs进行了定量分析,并对其分布特征、污染水平以及来源进行了探讨。结果显示:颗粒态PAHs的浓度范围为0.41~76.45μg.g-1,溶解态PAHs的浓度范围为32.57~108.47ng.L-1,西辽河PAHs的浓度比东辽河以及辽河干流中PAHs的浓度要高。在多环芳烃组成上,溶解态和颗粒态样品的PAHs均以低环数(二、三环)为主,且溶解态中低环数PAHs所占比例较颗粒态中所占的比例高。其中,溶解态中二环的PAHs比例最高(平均为68.19%),颗粒态中三环的PAHs比例最高(平均为66.28%)。相对于国内外其他河流,辽河流域的PAHs污染处于较低水平,部分河流受到一定程度的污染。辽河水系中PAHs的来源主要是以石油类和化石类燃料燃烧为主的混合源,这与辽宁复杂的能源结构密切相关。

  9. 镇江市老城区不同功能区街道灰尘中重金属污染的粒径分布及来源解析%The particle size distribution and source apportionment of heavy mental contaminated street dusts in different functional district of Zhenjiang

    Institute of Scientific and Technical Information of China (English)

    徐玮; 吕宾; 储金宇; 吴春笃; 周晓红; 蔡裕领; 韦媛媛

    2012-01-01

    在镇江市老城区的6个功能区(商业区、交通区、居民区、文教区、江滨公园、大市口)布设采样点,测定了街道灰尘样品中所含的7种重金属的含量,分析了街道灰尘中重金属污染的粒级效应;并基于主成分分析法对重金属的来源进行了解析.结果表明,总体来说,镇江市老城区街道灰尘中的重金属污染显示出明显的粒级效应,随灰尘粒径减小,重金属含量呈明显的递增趋势;镇江市老城区街道灰尘中的重金属来源有:(1)交通污染源,特征元素为Cu、Zn、Pb;(2)生活污染源,特征物质为有机质;(3)工业污染源,特征元素为Ni、Mn、Cr;(4)自然沉降源,即与成土母质的地质背景有关的土壤颗粒的再悬浮或迁移;(5)建筑废弃物及土壤扬尘,或是由几者产生的混合污染.%18 sampling sites were laid in six different functional areas (commercial area, traffic area, residential area, cultural and educational area, Riverside Park and Dashikou) of old town of Zhenjiang to collect the street dust samples. The content of 7 heavy metals in street dust was determined, the granularity effect of contaminated street dust was analyzed and the possible pollution source of heavy metals was investigated by using principal component analysis. The results indicated that the heavy metal pollution of street dust in Zhenjiang old town presented significant granularity effect, that was the content of heavy metals were greatly increased with the decreasing of dust size. The possible pollution sources of heavy metal in street dust were: (1) traffic emission, the feature elements were Cu, Zn and Pb; (2) domestic pollution, the feature elements was organic matter; (3) industrial pollution, the feature elements were Ni, Mn, Cr; (4) the re-suspension and transportation of soil particles which relating to geologic setting of parent material; (5) construction garbage and soil dust or the composite pollution from different source.

  10. ATMOSPHERIC AEROSOL SOURCE-RECEPTOR RELATIONSHIPS: THE ROLE OF COAL-FIRED POWER PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    Allen L. Robinson; Spyros N. Pandis; Cliff I. Davidson

    2004-12-01

    This report describes the technical progress made on the Pittsburgh Air Quality Study (PAQS) during the period of March 2004 through August 2004. Significant progress was made this project period on the analysis of ambient data, source apportionment, and deterministic modeling activities. Results highlighted in this report include evaluation of the performance of PMCAMx+ for an air pollution episode in the Eastern US, an emission profile for a coke production facility, ultrafine particle composition during a nucleation event, and a new hybrid approach for source apportionment. An agreement was reached with a utility to characterize fine particle and mercury emissions from a commercial coal fired power. Research in the next project period will include source testing of a coal fired power plant, source apportionment analysis, emission scenario modeling with PMCAMx+, and writing up results for submission as journal articles.

  11. Contributions to cities' ambient particulate matter (PM): A systematic review of local source contributions at global level

    Science.gov (United States)

    Karagulian, Federico; Belis, Claudio A.; Dora, Carlos Francisco C.; Prüss-Ustün, Annette M.; Bonjour, Sophie; Adair-Rohani, Heather; Amann, Markus

    2015-11-01

    For reducing health impacts from air pollution, it is important to know the sources contributing to human exposure. This study systematically reviewed and analysed available source apportionment studies on particulate matter (of diameter of 10 and 2.5 microns, PM10 and PM2.5) performed in cities to estimate typical shares of the sources of pollution by country and by region. A database with city source apportionment records, estimated with the use of receptor models, was also developed and available at the website of the World Health Organization. Systematic Scopus and Google searches were performed to retrieve city studies of source apportionment for particulate matter. Six source categories were defined. Country and regional averages of source apportionment were estimated based on city population weighting. A total of 419 source apportionment records from studies conducted in cities of 51 countries were used to calculate regional averages of sources of ambient particulate matter. Based on the available information, globally 25% of urban ambient air pollution from PM2.5 is contributed by traffic, 15% by industrial activities, 20% by domestic fuel burning, 22% from unspecified sources of human origin, and 18% from natural dust and salt. The available source apportionment records exhibit, however, important heterogeneities in assessed source categories and incompleteness in certain countries/regions. Traffic is one important contributor to ambient PM in cities. To reduce air pollution in cities and the substantial disease burden it causes, solutions to sustainably reduce ambient PM from traffic, industrial activities and biomass burning should urgently be sought. However, further efforts are required to improve data availability and evaluation, and possibly to combine with other types of information in view of increasing usefulness for policy making.

  12. Exploring the scope for complementary sub-global policy to mitigate CO2 from shipping

    International Nuclear Information System (INIS)

    For a high probability of avoiding dangerous interference with the climate system, all sectors must decarbonise over coming decades. Although shipping is an energy efficient transport mode, its emissions continue to grow. Compounding this, the sector's complexity, exclusion from emission inventories and slow progress towards a mitigation strategy, limit drivers towards meaningful change. Whilst there remains a preference within the industry for global mitigation policies, the urgency of required emission cuts necessitates exploration of complimentary sub-global measures. The debate surrounding such measures tends to focus on apportioning global shipping emissions to nations. To explore the policy implications of apportionment, the UK is used in this paper to illustrate how available apportionment regimes produce a wide range of emission estimates. Moreover, in the absence of transparent fuel consumption and freight data, they have limited sensitivity, rendering them currently obsolete for monitoring purposes. Nations, regions and organisations influence shipping, particularly in relation to operations, yet debate surrounding apportionment has arguably delayed consideration of sub-global polices and indicators. This paper makes a case for putting the apportionment debate aside in the short-term to open out the full span of options, consider influence over aspects of the shipping system, and how to monitor success. - Highlights: ► Debate on sub-global CO2 policies for shipping focuses on emission apportionment. ► Data limitations prevent apportionment regimes from monitoring policy success. ► Nations, regions and organisations directly influence shipping at sub-global levels. ► Sub-global policies influence demand and operations in ports/waters. ► Policy should focus on what can be influenced and consider how to monitor progress.

  13. 76 FR 55276 - Fisheries of the Exclusive Economic Zone Off Alaska; Octopus in the Bering Sea and Aleutian Islands

    Science.gov (United States)

    2011-09-07

    ... of the BSAI (76 FR 11139, March 1, 2011) and an apportionment from the non-specified reserve of groundfish (76 FR 17360, March 29, 2011). In accordance with Sec. 679.20(d)(2), the Administrator, Alaska... Economic Zone Off Alaska; Octopus in the Bering Sea and Aleutian Islands AGENCY: National Marine...

  14. 26 CFR 1.42-1T - Limitation on low-income housing credit allowed with respect to qualified low-income buildings...

    Science.gov (United States)

    2010-04-01

    ... State housing credit ceiling, or volume cap, described in paragraph (b) of this section. The authority... section. Upon apportionment of the State housing credit volume cap, each State or local housing credit... enacted on or before October 22, 1986, the date of enactment of the Tax Reform Act of 1986, shall be...

  15. 47 CFR 69.302 - Net investment.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 3 2010-10-01 2010-10-01 false Net investment. 69.302 Section 69.302... Apportionment of Net Investment § 69.302 Net investment. (a) Investment in Accounts 2001, 1220 and Class B Rural...) Investment in Accounts 2002, 2003 and to the extent such inclusions are allowed by this Commission,...

  16. 47 CFR 69.309 - Other investment.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 3 2010-10-01 2010-10-01 false Other investment. 69.309 Section 69.309... Apportionment of Net Investment § 69.309 Other investment. Investment that is not apportioned pursuant to §§ 69... category and access elements in the same proportions as the combined investment that is...

  17. Identifying the Sources Contributing to PM Exceedances in Ostrava, Czech Republic, Using Passive Aerosol Sampling Coupled with Computer-Controlled Microscopy

    Science.gov (United States)

    The Czech Hydrometeorological Institute (CHMI) in collaboration with the U.S. Environmental Protection Agency conducted a multi-pollutant source apportionment study in 2012 to quantify the impact of regional as well as local sources on air quality in the Ostrava metropolitan area...

  18. 47 CFR 69.310 - Capital leases.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 3 2010-10-01 2010-10-01 false Capital leases. 69.310 Section 69.310 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES (CONTINUED) ACCESS CHARGES Apportionment of Net Investment § 69.310 Capital leases. Capital Leases in Account 2680 shall be...

  19. 26 CFR 1.861-8 - Computation of taxable income from sources within the United States and from other sources and...

    Science.gov (United States)

    2010-04-01

    ... all other gross income. (3) Supportive functions. Deductions which are supportive in nature (such as... stewardship activities, see Examples 19 through 21 of paragraph (g) of this section. See paragraph (e)(4)(ii) of this section for the allocation and apportionment of deductions attributable to...

  20. 26 CFR 1.52-1 - Trades or businesses that are under common control.

    Science.gov (United States)

    2010-04-01

    ... control. 1.52-1 Section 1.52-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY INCOME TAX INCOME TAXES Tax Surcharge § 1.52-1 Trades or businesses that are under common control. (a) Apportionment of jobs credit among members of a group of trades or businesses that are under common...

  1. 38 CFR 3.500 - General.

    Science.gov (United States)

    2010-07-01

    ... last payment when reason for apportionment no longer exists. (2) Where pension was apportioned under... is later. (l) Guardian, marriage or divorce of (§ 3.856). Date of last payment (pending receipt of... citations affecting § 3.500, see the List of CFR Sections Affected, which appears in the Finding...

  2. Noncredit Education. Policy Brief

    Science.gov (United States)

    Community College League of California, 2014

    2014-01-01

    The current level of apportionment for Career Development and College Preparation (CDCP) enhanced noncredit classes and program--at only 71% of the credit rate--does not provide adequate funding for noncredit programs that endeavor to support job readiness, provide a gateway to enrollment in credit classes, and attract and retain quality faculty…

  3. 50 CFR 660.55 - Allocations.

    Science.gov (United States)

    2010-10-01

    ... Allocations. (a) General. An allocation is the apportionment of a harvest privilege for a specific purpose, to... fisheries (MS, C/P, and IFQ combined). The distribution of the whiting trawl allocation of POP to each... distribution of the whiting trawl allocation of widow to each sector (MS, C/P, and IFQ) will be done pro...

  4. 47 CFR 69.407 - Revenue accounting expenses in Account 6620.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 3 2010-10-01 2010-10-01 false Revenue accounting expenses in Account 6620. 69... SERVICES (CONTINUED) ACCESS CHARGES Apportionment of Expenses § 69.407 Revenue accounting expenses in Account 6620. (a) Revenue accounting expenses that are attributable to End User Common Line...

  5. 38 CFR 3.454 - Veterans disability pension.

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Veterans disability pension. 3.454 Section 3.454 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS... disability pension. Apportionment of disability pension will be as follows: (a) Where a veteran with...

  6. 38 CFR 3.459 - Death compensation.

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Death compensation. 3.459..., Compensation, and Dependency and Indemnity Compensation Apportionments § 3.459 Death compensation. (a) Death compensation will be apportioned if the child or children of the deceased veteran are not in the custody of...

  7. 38 CFR 3.460 - Death pension.

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Death pension. 3.460 Section 3.460 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS ADJUDICATION Pension, Compensation, and Dependency and Indemnity Compensation Apportionments § 3.460 Death pension. Death...

  8. Courses to be Deleted from the Credit and Noncredit Program of the Community Colleges.

    Science.gov (United States)

    Petersen, Allan L.

    This report describes the procedures employed in the preparation of a list of courses to be deleted from the credit and noncredit programs of the California community colleges in response to a $30 million deduction from the total community college apportionments. The first section presents background on the 1982-83 budget bill, specifies three…

  9. 26 CFR 1.168(i)-0 - Table of contents for the general asset account rules.

    Science.gov (United States)

    2010-04-01

    ... recovery period and/or depreciation method. (i) No effect on general asset account election. (ii) Asset is...) General rules. (ii) Special rules. (d) Determination of depreciation allowance. (1) In general. (2...) Source determined by allocation and apportionment of depreciation allowed. (ii) Formula for...

  10. 33 CFR 277.3 - References.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false References. 277.3 Section 277.3... References. (a) Section 6, Pub. L. 647, 67th Congress, 21 June 1940, as amended (33 U.S.C. 516). (Appendix A...) Coast Guard reference: COMDT (G-OPT-3), Exemplification-Principles of Apportionment of Cost...

  11. 26 CFR 1.611-3 - Rules applicable to timber.

    Science.gov (United States)

    2010-04-01

    ... seedlings. The apportionment of deductions between the several owners of economic interests in standing... valuation and accounting. (1) With a view to logical and reasonable valuation of timber, the taxpayer shall... or shares, royalties and rentals, valuation for local or State taxation, partnership...

  12. 26 CFR 1.611-2 - Rules applicable to mines, oil and gas wells, and other natural deposits.

    Science.gov (United States)

    2010-04-01

    ... year to the economic limit of production. Taxpayers computing depletion by this method must keep... aggregation. (6) The apportionment of the deduction among the several owners of economic interests in the... units of the mineral products in the deposit for the purposes of valuation and depletion shall...

  13. 47 CFR 69.408 - All other customer services expenses in Account 6620.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 3 2010-10-01 2010-10-01 false All other customer services expenses in Account... CARRIER SERVICES (CONTINUED) ACCESS CHARGES Apportionment of Expenses § 69.408 All other customer services expenses in Account 6620. All other customer services expenses shall be apportioned among the...

  14. 47 CFR 69.403 - Marketing expense (Account 6610).

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 3 2010-10-01 2010-10-01 false Marketing expense (Account 6610). 69.403 Section 69.403 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES (CONTINUED) ACCESS CHARGES Apportionment of Expenses § 69.403 Marketing expense (Account 6610)....

  15. Visibility assessment : Monte Carlo characterization of temporal variability.

    Energy Technology Data Exchange (ETDEWEB)

    Laulainen, N.; Shannon, J.; Trexler, E. C., Jr.

    1997-12-12

    Current techniques for assessing the benefits of certain anthropogenic emission reductions are largely influenced by limitations in emissions data and atmospheric modeling capability and by the highly variant nature of meteorology. These data and modeling limitations are likely to continue for the foreseeable future, during which time important strategic decisions need to be made. Statistical atmospheric quality data and apportionment techniques are used in Monte-Carlo models to offset serious shortfalls in emissions, entrainment, topography, statistical meteorology data and atmospheric modeling. This paper describes the evolution of Department of Energy (DOE) Monte-Carlo based assessment models and the development of statistical inputs. A companion paper describes techniques which are used to develop the apportionment factors used in the assessment models.

  16. PM10 standards and nontraditional particulate source controls: Research perspective

    International Nuclear Information System (INIS)

    Knowledge of how to measure suspended particles, what their concentrations are, what they are composed of, and where they come from has increased substantially since 1975. At that time, much of the pioneering work in these areas was just being conducted and published. Size-classified measurements, low-level elemental analysis, inorganic ion analysis, and carbon determinations for aerosol samples were novel research developments. Receptor modeling was not considered to be a scientific discipline, let alone a useful tool for source apportionment. Presentations at earlier conferences went to great lengths to document and justify methodologies which are taken for granted at this conference. This paper goes on to discuss research findings in control of wood smoke, fugitive dusts, motor vehicle exhausts, and secondary aerosols. Research results in source apportionment are also discussed

  17. Use of Lead Isotopes to Identify Sources of Metal and Metalloid Contaminants in Atmospheric Aerosol from Mining Operations

    OpenAIRE

    Félix, Omar I.; Csavina, Janae; Field, Jason; Kyle P. Rine; Sáez, A. Eduardo; Betterton, Eric A.

    2014-01-01

    Mining operations are a potential source of metal and metalloid contamination by atmospheric particulate generated from smelting activities, as well as from erosion of mine tailings. In this work, we show how lead isotopes can be used for source apportionment of metal and metalloid contaminants from the site of an active copper mine. Analysis of atmospheric aerosol shows two distinct isotopic signatures: one prevalent in fine particles (< 1 μm aerodynamic diameter) while the other corresponds...

  18. Reforming the taxation of multijurisdictional enterprises in Europe: coopetition in a bottom-up federation

    OpenAIRE

    Gérard, Marcel

    2006-01-01

    This paper investigates replacing separate taxation by consolidation and formulary apportionment in a Bottom-up Federation, when a multijurisdictional firm is mobile in various respects. The reform is decided cooperatively by all the jurisdictions or by some of them, while tax rates remain within the competence of each jurisdiction. The paper sets forth the conditions for the reform to be social welfare enhancing, while not increasing tax competition. Among them, the formula should emphasize ...

  19. On the scope of the EEG allocation. At the same time a comment to the decision of the Higher Regional Court Frankfurt a.M. from 25th April 2012; Zur Reichweite der EEG-Umlage. Zugleich eine Anmerkung zum Beschluss des Oberlandesgerichts Frankfurt a.M. vom 25.04.2012

    Energy Technology Data Exchange (ETDEWEB)

    Fricke, Hanns-Christian [Kanzlei Dr. Fricke und Collegen, Hannover (Germany)

    2012-09-15

    Since the establishment of the Renewable Energy Law (EEG) it is argued about the question of whether a participation in the EEG apportionment method can be avoided in the context of energy supply contracts. With the EEG amendment 2012, for the first time the legislature has now implemented a self-supply regulation in the law. The contribution under consideration reports on the resulting consequences for the practice.

  20. Functional Hazard Analysis for Railway Safety

    OpenAIRE

    RAFRAFI,M; El-Koursi, Em

    2007-01-01

    The apportionment of railway safety targets is a key issue to develop a common safety management in the European railway system. In this paper, we develop a generic approach based on the Functional Hazard Analysis (FHA), to analyse the safety of railway systems for a unified European network and to comply with the Common Safety Targets (CSTs) required by the European railway safety directive. We suggest to combine the FHA technique with the functional railway architecture, developed by the AE...

  1. Age- and Gender-Related Mean Hearing Threshold in a Highly-Screened Population: The Korean National Health and Nutrition Examination Survey 2010–2012

    OpenAIRE

    Park, Yun Hwi; Shin, Seung-Ho; Byun, Sung Wan; Kim, Ju Yeon

    2016-01-01

    Background In evaluating hearing disability in medicolegal work, the apportionment of age- and gender-related sensorineural hearing loss should be considered as a prior factor, especially for the elderly. However, in the literature written in the English language no studies have reported on the age- and gender-related mean hearing threshold for the South Korean population. Objective This study aimed to identify the mean hearing thresholds in the South Korean population to establish reference ...

  2. Establishing the origin of particulate matter across Europe

    Science.gov (United States)

    Schaap, Martijn; Kranenburg, Richard; Hendriks, Carlijn; Kuenen, Jeroen

    2016-04-01

    Exposure to particulate matter (PM) in ambient air leads to adverse health effects. To design cost effective mitigation strategies, a thorough understanding of the sources of particulate matter is crucial. In this paper we like to provide an overview of recent source apportionment studies aimed at PM and its precursors carried out at TNO. The source apportionment module that tracks the origin of modelled particulate matter distributions throughout a LOTOS-EUROS simulation will be explained. To optimally apply this technology dedicated emission inventories, e.g. fuel type specific, need to be generated. Applications to Europe shows that in northwestern Europe the contribution of transport and agricultural emissions dominate the PM mass concentrations, especially during episodic events. In eastern Europe, the domestic and energy sector are much more important. In southern Europe the picture is more mixed, although the frequent high levels of desert dust stand out. Evaluation of the source allocation against experimental data and PMF analyses is challenging as there is only a limited availability of source specific tracers or factors that can be used for direct comparison. Nonetheless, for the available tracers such as vanadium for heavy fuel oil combustion an evaluation is very well possible. The source apportionment technique can also be used to interpret particulate matter formation efficiencies. It will be shown that the conversion rates for the secondary inorganic aerosol precursors (NOx, NH3 and SO2) have changed during the last 20 years. A particular problem is related to the fact that CTMs systematically underestimate observed PM levels, which means that the contribution of certain source categories (natural, agriculture, combustion) are underestimated. Future developments needed to improve the source apportionment information concerning process knowledge, data assimilation as well as model implementation will be discussed. Specific challenges concerning the

  3. Snowpack regimes of the Western United States

    OpenAIRE

    Trujillo, Ernesto; Molotch, Noah P.

    2014-01-01

    Snow accumulation and melt patterns play a significant role in the water, energy, carbon, and nutrient cycles in the montane environments of the Western United States. Recent studies have illustrated that changes in the snow/rainfall apportionments and snow accumulation and melt patterns may occur as a consequence of changes in climate in the region. In order to understand how these changes may affect the snow regimes of the region, the current characteristics of the snow accumulation and mel...

  4. Implications of the introduction of the Common Consolidated Corporate Tax Base for tax revenues in Romania

    Directory of Open Access Journals (Sweden)

    Daniela Pirvu

    2011-06-01

    Full Text Available In order to address some existing difficulties in corporate income taxation (CIT, the European Commission proposed the introduction of measures for coordination, a solution contested by some member states but supported by most professionals and many organizations representing the interests of European employers. Disputes in connection with the introduction of the Common Consolidated Corporate Tax Base (CCCTB are occasioned by the uncertainty regarding its effects. Since CIT makes an important contribution to the forming of central budget revenues, the CCCTB is a challenge for Romanian public authorities. The Romanian government has not made clear its options in this respect. In this paper we present the main points of view about the implications of introducing the CCCTB as seen by specialists and estimate the effects of the EU formula apportionment on CIT revenues in Romania.According to research results on a sample of companies in 2006-09, Romania will assume a loser position if the EU formula apportionment uses the payroll (although the loss of tax revenue would be lower than other researchers have estimated and a winner position if the EU formula apportionment does not use the payroll.

  5. A hybrid modeling approach for estimating reactive nitrogen deposition in Rocky Mountain National Park

    Science.gov (United States)

    Malm, William C.; Rodriguez, Marco A.; Schichtel, Bret A.; Gebhart, Kristi A.; Thompson, Tammy M.; Barna, Michael G.; Benedict, Katherine B.; Carrico, Christian M.; Collett, Jeffrey L.

    2016-02-01

    Changes in ecosystem function at Rocky Mountain National Park (RMNP) are occurring because of nitrogen deposition associated with emissions of nitrogen from sources in Colorado as well as other areas of the North American continent and beyond. Nitrogen species are in both reduced and oxidized forms. A year-long monitoring program was initiated to better understand their origins as well as the complex chemistry occurring during transport from source to receptor. Specifically, the goals of the study were to characterize the atmospheric concentrations of nitrogen species in gaseous, particulate, and aqueous phases in RMNP and to identify the emission sources of these various species. The apportionment strategy was designed to focus on differentiating between sources within and outside the state of Colorado and then further differentiate between sources along the Front Range of Colorado and the rest of Colorado. It was also desirous to identify the relative contributions to atmospheric nitrogen species from mobile sources, agricultural activities, and large and small point sources within the state of Colorado. The Particle Source Apportionment Technology (PSAT) module available in the chemical transport model, the Comprehensive Air quality Model with extensions (CAMx), is used to develop first-principle estimates of the contributions from different areas of North America. The CAMx_PSAT results are combined with measured species concentrations in a receptor modeling approach to develop final estimates of source apportionment of the various species' concentrations and deposition.

  6. Evaluating analytical approaches for estimating pelagic fish biomass using simulated fish communities

    Science.gov (United States)

    Yule, Daniel L.; Adams, Jean V.; Warner, David M.; Hrabik, Thomas R.; Kocovsky, Patrick M.; Weidel, Brian C.; Rudstam, Lars G.; Sullivan, Patrick J.

    2013-01-01

    Pelagic fish assessments often combine large amounts of acoustic-based fish density data and limited midwater trawl information to estimate species-specific biomass density. We compared the accuracy of five apportionment methods for estimating pelagic fish biomass density using simulated communities with known fish numbers that mimic Lakes Superior, Michigan, and Ontario, representing a range of fish community complexities. Across all apportionment methods, the error in the estimated biomass generally declined with increasing effort, but methods that accounted for community composition changes with water column depth performed best. Correlations between trawl catch and the true species composition were highest when more fish were caught, highlighting the benefits of targeted trawling in locations of high fish density. Pelagic fish surveys should incorporate geographic and water column depth stratification in the survey design, use apportionment methods that account for species-specific depth differences, target midwater trawling effort in areas of high fish density, and include at least 15 midwater trawls. With relatively basic biological information, simulations of fish communities and sampling programs can optimize effort allocation and reduce error in biomass estimates.

  7. A clustering algorithm for sample data based on environmental pollution characteristics

    Science.gov (United States)

    Chen, Mei; Wang, Pengfei; Chen, Qiang; Wu, Jiadong; Chen, Xiaoyun

    2015-04-01

    Environmental pollution has become an issue of serious international concern in recent years. Among the receptor-oriented pollution models, CMB, PMF, UNMIX, and PCA are widely used as source apportionment models. To improve the accuracy of source apportionment and classify the sample data for these models, this study proposes an easy-to-use, high-dimensional EPC algorithm that not only organizes all of the sample data into different groups according to the similarities in pollution characteristics such as pollution sources and concentrations but also simultaneously detects outliers. The main clustering process consists of selecting the first unlabelled point as the cluster centre, then assigning each data point in the sample dataset to its most similar cluster centre according to both the user-defined threshold and the value of similarity function in each iteration, and finally modifying the clusters using a method similar to k-Means. The validity and accuracy of the algorithm are tested using both real and synthetic datasets, which makes the EPC algorithm practical and effective for appropriately classifying sample data for source apportionment models and helpful for better understanding and interpreting the sources of pollution.

  8. Approaches to Children's Exposure Assessment: Case Study with Diethylhexylphthalate (DEHP).

    Science.gov (United States)

    Ginsberg, Gary; Ginsberg, Justine; Foos, Brenda

    2016-01-01

    Children's exposure assessment is a key input into epidemiology studies, risk assessment and source apportionment. The goals of this article are to describe a methodology for children's exposure assessment that can be used for these purposes and to apply the methodology to source apportionment for the case study chemical, diethylhexylphthalate (DEHP). A key feature is the comparison of total (aggregate) exposure calculated via a pathways approach to that derived from a biomonitoring approach. The 4-step methodology and its results for DEHP are: (1) Prioritization of life stages and exposure pathways, with pregnancy, breast-fed infants, and toddlers the focus of the case study and pathways selected that are relevant to these groups; (2) Estimation of pathway-specific exposures by life stage wherein diet was found to be the largest contributor for pregnant women, breast milk and mouthing behavior for the nursing infant and diet, house dust, and mouthing for toddlers; (3) Comparison of aggregate exposure by pathways vs biomonitoring-based approaches wherein good concordance was found for toddlers and pregnant women providing confidence in the exposure assessment; (4) Source apportionment in which DEHP presence in foods, children's products, consumer products and the built environment are discussed with respect to early life mouthing, house dust and dietary exposure. A potential fifth step of the method involves the calculation of exposure doses for risk assessment which is described but outside the scope for the current case study. In summary, the methodology has been used to synthesize the available information to identify key sources of early life exposure to DEHP. PMID:27376320

  9. Numerical simulations on polarized photon scattering for classification of air pollutants

    Science.gov (United States)

    Li, Da; Zeng, Nan; Zeng, Maomao; Ma, Hui

    2015-11-01

    Atmospheric pollution has become a key factor restricting the development of social economy. Identification of major pollutants has important scientific significance. The polarization evolution during polarized light interacting with particulate matters can provide important information sensitive to properties of particles. We propose a method to recognize the specific component in air dust, for example, the sand. Based on our polarization simulation, we show theoretically that some Stokes parameters at specific scattering angle can classify water soluble particles, water droplet and sand etc. The preliminary research implies some potential of polarization detection applied in source apportionment for air pollution monitoring.

  10. Stable carbon isotope ratios of lipid biomarkers and their applications in the marine environment

    International Nuclear Information System (INIS)

    Studies on the distribution of lipid biomarkers in the environment help elucidate biogeochemical processes, but recent findings have significantly reduced the specificity of some biomarkers. The analytical development of Gas Chromatography-Combustion-IRMS (GC-C-IRMS) allows the determination of the δ13C of specific biomarkers, thereby improving the veracity of source apportionment. In this report, we present a brief description of the analytical approach for sample preparation and carbon isotope measurements of individual biomarkers. Selected examples of the applications in the use of GC-C-IRMS for biomarker source elucidation in the marine environment and potential applications to paleoclimatological studies are reviewed. (author)

  11. Further promotion of the use of mosses and lichens for studies of atmospheric deposition of trace elements

    International Nuclear Information System (INIS)

    Some recent and ongoing studies related to the use of mosses as biomonitors of atmospheric metal deposition are briefly reviewed. Issues discussed in particular are the conversion of concentration in moss to absolute deposition values, introduction of a second-generation ICP-MS instrument for moss analysis, determination of stable lead isotope ratios in mosses for source apportionment, and temporal trends of lead and cadmium deposition in Norway. A novel nuclear technique for the determination of fluorine in mosses surrounding an aluminium smelter is presented. (author)

  12. Understanding the Nuttiness of State Tax Policy: When States Have Both Too Much Sovereignty and Not Enough

    OpenAIRE

    McLure, Charles E. Jr.

    2005-01-01

    Much of this nuttiness, the part related to lack of uniformity and consistency across states, the legal inability to implement policies that would make good sense, and the part that involves state beggar–thy–neighbor tax policies, such as sales–only apportionment and the failure to require combination of unitary businesses, is rooted in our system of government. As my title says, the individual states have both too much sovereignty over tax policy and not enough. I will use the lack of coordi...

  13. Aerosol characterization at the Saharan AERONET site Tamanrasset

    Directory of Open Access Journals (Sweden)

    C. Guirado

    2014-06-01

    AOD ~ 0.39 at 440 nm and a deep CBL. The aerosol-type characterization shows desert mineral dust as prevailing aerosol. Both pure Saharan dust and very clear sky conditions are observed depending on the season. However, several case studies indicate an anthropogenic fine mode contribution from Libya and Algeria's industrial areas. The Concentration Weighted Trajectory (CWT source apportionment method was used to identify potential sources of air masses arriving at Tamanrasset at several heights for each season. Microphysical and optical properties and precipitable water vapour were also investigated.

  14. MixBC Method: a New Approach for Distribution of Indirect Costs and Expenses to Products

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Pereira Soares

    2013-02-01

    Full Text Available In cost management, the products cost is a valuable and necessary information. Nevertheless, distributing indirect costs and expenses to products may involve several uncertainties, what can lead to imprecise results and decision mistakes. The aim of this paper is to construct a method that would reduce the uncertainties found in current costing processes, by modelling and providing the analytical deduction of the method MixBC – Mix Based Costing. In sequence, there was performed an example of construction projects costing using MixBC. By analysing different production scenarios, this method permits indirect costs and expenses to be distributed among the products without the need of arbitrary apportionment.

  15. Air Quality Monitoring Programme

    DEFF Research Database (Denmark)

    Kemp, K.; Palmgren, F.

    The air quality in Danish cities has been monitored continuously since 1982 within the Danish Air Quality (LMP) network. The aim has been to follow the concentration levels of toxic pollutants in the urban atmosphere and to provide the necessary knowledge to assess the trends, to perform source...... apportionment, and to evaluate the chemical reactions and the dispersion of the pollutants in the atmosphere. In 2002 the air quality was measured in four Danish cities and at two background sites. NO2 and PM10 were at several stations found in concentrations above the new EU limit values, which the Member...

  16. Characterization of individual particles in gaseous media by mass spectrometry

    Science.gov (United States)

    Sinha, M. P.

    1990-01-01

    An introduction is given to a system for particle analysis by mass spectrometry (PAMS) which employs particle-beam techniques to measure mass spectra on a continuous real-time basis. The system is applied to particles of both organic and inorganic compounds, and the measurements give the chemical characteristics of particles in mixtures and indicate source apportionment. The PAMS system can be used for process control and studying heterogeneous/catalytic reactions in particles, and can be fitted to study the real-time attributes of PAMS.

  17. Final report of the IAEA advisory group meeting on accelerator-based nuclear analytical techniques for characterization and source identification of aerosol particles

    International Nuclear Information System (INIS)

    The field of aerosol characterization and source identification covers a wide range of scientific and technical activities in many institutions, in both developed and developing countries. This field includes research and applications on urban air pollution, source apportionment of suspended particulate matter, radioactive aerosol particles, organic compounds carried on particulate matter, elemental characterization of particles, and other areas. The subject of this AGM focused on the use of accelerator-based nuclear analytical techniques for determination of elemental composition of particles (by either bulk or single particle analysis) and the use of accumulated knowledge for source identification

  18. Identifying and quantifying transported vs. local sources of New York City PM 2.5 fine particulate matter air pollution

    Science.gov (United States)

    Lall, Ramona; Thurston, George D.

    New York City (NYC) is presently in violation of the nation's PM 2.5 annual mass standard, and will have to take actions to control the sources contributing to these violations. This paper seeks to differentiate the impact of long-range transported aerosols on the air quality of downtown NYC, so that the roles of local sources can more clearly be evaluated. Past source apportionment studies have considered single sites individually in their source apportionment analyses to identify and determine sources affecting that site, often finding secondary sulfates to be an important contributor, but not being able to quantify the portion that is transported vs. local. In this study, a rural site located in Sterling Forest, NY, which is near to the NYC area, but unaffected by local NYC sources, is instead used as a reference to separate the portion of the aerosol that is transported to our Manhattan, NYC site before conducting the source apportionment analysis. Sterling Forest is confirmed as a background site via elemental comparisons with NYC during regional transport episodes of Asian and Sahara sandstorm dusts, as well as by comparisons with a second background site in Chester, NJ. Two different approaches that incorporate Sterling Forest background data into the NYC source apportionment analysis are then applied to quantify local vs. transported aerosols. Six source categories are identified for NYC: regional transported sulfate, trans-continental desert dust, traffic, residual oil, "local" dust and World Trade Center fires pollution. Of these, the transported sulfates and trans-continental desert dust accounted for nearly half of the total PM 2.5 mass in Manhattan during 2001, with more than half coming from these transported sources during the summer months. More than 90% of the Manhattan elemental carbon was found to be of local origins. Conversely, roughly 90% of the NYC sulfate mass was identified as transported into the city. Our results indicate that transported

  19. Public notice of recommendations made by the Reactor Safety Commission

    International Nuclear Information System (INIS)

    To summarize, the RSC is of the opinion that from its own point of view there are no objections against the construction of the second power station block (KWU-DWR, 3,765 MWth 1,281 MWel) at the chosen site. The RSC believes that even with the operation of two blocks, taking into account the loads, already present it will be possible to keep within the recommended dose values. The apportionment of release rates can be defined conclusively in a joint waste air and waste water discharge plan, whereby the results of the measuring programme for KKP 1 can be taken notice of. (orig.)

  20. Modelling VOC source impacts on high ozone episode days observed at a mountain summit in Hong Kong under the influence of mountain-valley breezes

    Science.gov (United States)

    Lam, S. H. M.; Saunders, S. M.; Guo, H.; Ling, Z. H.; Jiang, F.; Wang, X. M.; Wang, T. J.

    2013-12-01

    A top-down approach to evaluate high ozone (O3) formation, attributed to different emission sources, is developed for anti-cyclonic conditions in a region of Hong Kong influenced by meso-scale circulations. A near-explicit photochemical model coupled with the Master Chemical Mechanism (MCMv3.2) is used to investigate the chemical characteristics in the region. Important features have been enhanced in this model including the photolysis rates, simulated by the National Center for Atmospheric Research (NCAR) Tropospheric Ultraviolet and Visible (TUV) Radiation Model, as well as hourly variation of Volatile Organic Compound (VOC) concentration input from on-site sampling. In general, the combined model gives a reasonably good representation of high O3 levels in the region. The model successfully captured a multi-day O3 event in the autumn of 2010. Source apportionment via Positive Matrix Factorization (PMF) was carried out on the sampled VOC data, to determine the major sources in the region. Based on the outcomes of the PMF source apportionment, a sensitivity analysis using the developed photochemical model was conducted and used to estimate O3 reduction under different source removal regimes. Results indicate that vehicular emissions are the dominant VOC source contributing to O3 formation. This study has demonstrated a potentially efficient secondary pollutants control methodology, using a combined field measurements and modelling approach.

  1. Use of lead isotopes to identify sources of metal and metalloid contaminants in atmospheric aerosol from mining operations.

    Science.gov (United States)

    Félix, Omar I; Csavina, Janae; Field, Jason; Rine, Kyle P; Sáez, A Eduardo; Betterton, Eric A

    2015-03-01

    Mining operations are a potential source of metal and metalloid contamination by atmospheric particulate generated from smelting activities, as well as from erosion of mine tailings. In this work, we show how lead isotopes can be used for source apportionment of metal and metalloid contaminants from the site of an active copper mine. Analysis of atmospheric aerosol shows two distinct isotopic signatures: one prevalent in fine particles (environment. The lead isotopic ratios found in the fine particles are equal to those of the mine that provides the ore to the smelter. Topsoil samples at the mining site show concentrations of Pb and As decreasing with distance from the smelter. Isotopic ratios for the sample closest to the smelter (650m) and from topsoil at all sample locations, extending to more than 1km from the smelter, were similar to those found in fine particles in atmospheric dust. The results validate the use of lead isotope signatures for source apportionment of metal and metalloid contaminants transported by atmospheric particulate. PMID:25496740

  2. Use of Lead Isotopes to Identify Sources of Metal and Metalloid Contaminants in Atmospheric Aerosol from Mining Operations

    Science.gov (United States)

    Félix, Omar I.; Csavina, Janae; Field, Jason; Rine, Kyle P.; Sáez, A. Eduardo; Betterton, Eric A.

    2014-01-01

    Mining operations are a potential source of metal and metalloid contamination by atmospheric particulate generated from smelting activities, as well as from erosion of mine tailings. In this work, we show how lead isotopes can be used for source apportionment of metal and metalloid contaminants from the site of an active copper mine. Analysis of atmospheric aerosol shows two distinct isotopic signatures: one prevalent in fine particles (< 1 μm aerodynamic diameter) while the other corresponds to coarse particles as well as particles in all size ranges from a nearby urban environment. The lead isotopic ratios found in the fine particles are equal to those of the mine that provides the ore to the smelter. Topsoil samples at the mining site show concentrations of Pb and As decreasing with distance from the smelter. Isotopic ratios for the sample closest to the smelter (650 m) and from topsoil at all sample locations, extending to more than 1 km from the smelter, were similar to those found in fine particles in atmospheric dust. The results validate the use of lead isotope signatures for source apportionment of metal and metalloid contaminants transported by atmospheric particulate. PMID:25496740

  3. The effects of the German feed-in tariffs for renewable electricity generation on the German energy system. An analysis with the energy system model TIMES-D; Die Auswirkungen des EEG auf das Energiesystem Deutschlands. Eine Betrachtung mit dem Energiesystemmodell TIMES-D

    Energy Technology Data Exchange (ETDEWEB)

    Goetz, Birgit; Voss, Alfred; Blesl, Markus; Fahl, Ulrich [Stuttgart Univ. (Germany). Inst. fuer Energiewirtschaft und Rationelle Energieanwendung

    2011-09-15

    In Germany, the electricity generation from renewable energy has been promoted since the year 2000 by a feed-in tariff system, the Renewable Energy Sources Act (EEG). This article evaluates the long-term impact of the German feed-in tariffs on the development of the German energy system with the help of the energy system model TIMES-D. In the model-based analysis, both the payment side (i.e. the tariffs) and the cost side (i.e. the EEG apportionment) are taken into consideration. Through the promotion of the feed-in tariff system - in combination with the European Emission Trading Scheme (ETS) - the use of renewable energies in electricity generation in Germany rises considerably such that renewable energy sources account for almost 40% of total gross electricity consumption in 2030. Accordingly, until 2020 total EEG fee payments as well as the EEG apportionment increase significantly. The impact of the feed-in tariff system on final electricity demand is, however, relatively small. Alternative scenario settings show that the expansion of the renewable electricity generation through the feed-in tariff system clearly exceeds the development which would occur when trying to reach the reduction targets of the ETS in a cost-efficient way. (orig.)

  4. Chemical mass balance estimation of arsenic in atmospheric dust fall out in an urban residential area, Raipur, Central India

    Directory of Open Access Journals (Sweden)

    G. Balakrishna

    2010-11-01

    Full Text Available The components and quantities of atmospheric dust fallout have been reported to be the pollution indicator of large urban areas. The multiplicity and complexity of sources of atmospheric dusts in urban regions has put forward the need of source apportionment of these sources indicating their contribution to specific environmental receptor. The study presented here is focused on investigation of source contribution estimates of Arsenic in urban dust fallout in an urban-industrial area, Raipur, India. Source-receptor based representative sampling plan using longitudinal study design has been adopted. Six sampling sites have been identified on the basis of land use for development plan of anthropogenic activities and factors related to the transportation and dispersion pattern of atmospheric dusts. Source apportionment has been done using Chemical Mass Balance (CMB 8. Good fit parameters and relative source contribution has been analyzed and documented. Dominance of coal fired industries sources on arsenic levels measured at selected ambient residential receptors compared to line sources has been observed. Road-traffic has shown highest contribution of dust at indoor houses and out door-street automobile exhaust has shows highest contribution for arsenic. The results of CMB output and regression data of source-receptor dust matrices have shown comparable pattern.

  5. Precipitation variability assessment of northeast China: Songhua River basin

    Science.gov (United States)

    Khan, Muhammad Imran; Liu, Dong; Fu, Qiang; Azmat, Muhammad; Luo, Mingjie; Hu, Yuxiang; Zhang, Yongjia; Abrar, Faiz M.

    2016-07-01

    Variability in precipitation is critical for the management of water resources. In this study, the research entropy base concept was applied to investigate spatial and temporal variability of the precipitation during 1964-2013 in the Songhua River basin of Heilongjiang Province in China. Sample entropy was applied on precipitation data on a monthly, seasonally, annually, decade scale and the number of rainy days for each selected station. Intensity entropy and apportionment entropy were used to calculate the variability over individual year and decade, respectively. Subsequently, Spearman's Rho and Mann-Kendall tests were applied to observe for trends in the precipitation time series. The statistics of sample disorder index showed that the precipitation during February (mean 1.09, max. 1.26 and min. 0.80), April (mean 1.12, max. 1.29 and min. 0.99) and July (mean 1.10, max. 1.20 and min. 0.98) contributed significantly higher than those of other months. Overall, the contribution of the winter season was considerably high with a standard deviation of 0.10. The precipitation variability on decade basis was observed to increase from decade 1964-1973 and 1994-2003 with a mean value of decadal apportionment disorder index 0.023 and 0.053, respectively. In addition, the Mann-Kendall test value (1.90) showed a significant positive trend only at the Shangzhi station.

  6. Biomonitoring of trace element air pollution: Principles, possibilities and perspectives

    International Nuclear Information System (INIS)

    The present paper discusses the biomonitoring of trace element air pollution. Much attention is given to both lichens and mosses as the dominant plant species used in biomonitoring surveys. Biomonitoring is regarded as a means to assess trace element concentrations in aerosols and deposition. This implies that the monitor should concentrate the elements of interest and quantitatively reflect its elemental ambient conditions. Environmental impact on the biomonitor's behaviour is viewed as resulting in changes in the dose-response relationships. The current literature is briefly reviewed, for plant's behaviour modelling, for laboratory studies on physiological processes responsible for accumulation, retention, and release, and for fieldwork on quantification of dose-response relationships. Monitoring of elemental atmospheric availability is presented as deriving its relevance from presumed impact on both ecosystem performance and human health; source apportionment is regarded as an important parallel result for purposes of emission regulatory management. For source apportionment, the paper argues in favour of multi-elemental determinations, supplemented by information on organic compounds and elemental chemical forms. Furthermore, the discussion points towards more explicit coupling of biomonitoring data to knowledge and databases on emission registration, ecosystem performance, and human health. This means that multidisciplinary programs should be set up, which accommodate expert inputs from biomonitoring, emission control programs, analytical chemistry, ecology, and epidemiology. (author)

  7. Groundwater Challenges of the Lower Rio Grande: A Case Study of Legal Issues in Texas and New Mexico

    Directory of Open Access Journals (Sweden)

    Elizabeth Wheat

    2015-03-01

    Full Text Available In 1938, Texas, New Mexico, and Colorado signed the Rio Grande Compact, establishing terms of apportionment for some of the water from the Rio Grande for the three states. Following congressional approval in 1939, this compact governs water allocation in a region with a variable climate and frequent drought conditions and established the Rio Grande Compact Commission, comprised of a commissioner from each state and one from the federal government, to enforce the compact. With an increasing population and declining surface water supply, the Compact has been tested among the parties and within the states themselves. In a case currently before the U.S. Supreme Court, Texas v. New Mexico and Colorado (2013, Texas claims New Mexico is violating the Compact and Rio Grande Project Act by using water in excess of its apportionment through its allowance of diversions of surface and groundwater. The issue is further compounded by disputes within Texas over separate legal regimes for groundwater and surface water. Combined with growing scarcity issues, the allocation of water in the Lower Rio Grande presents a timely natural resource challenge. This review explores legal issues involved in the case as well as growing challenges of population growth, agricultural development needs, and water shortages.

  8. Nursing care process for releasing psychiatric inpatients from long-term seclusion in Japan: modified grounded theory approach.

    Science.gov (United States)

    Nagayama, Yutaka; Hasegawa, Masami

    2014-09-01

    Based on a modified grounded theory approach, in this study, we sought to elucidate the nursing care process used to guide psychiatric inpatients in long-term seclusion towards release from seclusion. Participant observations and interviews were conducted with a total of 18 nurses from three long-term psychiatric wards at two institutions from September 2011 to November 2012, to collect data on the nursing care they provided for psychiatric patients in long-term seclusion. Consequently, four categories and 15 concepts were extracted. The nurses viewed "a mature therapeutic environment that utilizes flexible apportionment of care" as the foundation (i.e. the core category) in guiding psychiatric inpatients towards release from long-term seclusion. The results revealed a care structure in which nurses in such a treatment environment provided care by flexible apportionment of three types of care: care aimed at avoiding mental and physical exhaustion, standardized care that does not confer a disadvantage to patients, and immediately responding to prevent problematic behaviors.

  9. The ambient aerosol characterization during the prescribed bushfire season in Brisbane 2013.

    Science.gov (United States)

    Milic, A; Miljevic, B; Alroe, J; Mallet, M; Canonaco, F; Prevot, A S H; Ristovski, Z D

    2016-08-01

    Prescribed burnings are conducted in Queensland each year from August until November aiming to decrease the impact of bushfire hazards and maintain the health of vegetation. This study reports chemical characteristics of the ambient aerosol, with a focus on source apportionment of the organic aerosol (OA) fraction, during the prescribed biomass burning (BB) season in Brisbane 2013. All measurements were conducted within the International Laboratory for Air Quality and Health (ILAQH) located in Brisbane's Central Business District. Chemical composition, degree of ageing and the influence of BB emission on the air quality of central Brisbane were characterized using a compact Time of Flight Aerosol Mass Spectrometer (cToF-AMS). AMS loadings were dominated by OA (64%), followed by, sulfate (17%), ammonium (14%) and nitrates (5%). Source apportionment was applied on the AMS OA mass spectra via the multilinear engine solver (ME-2) implementation within the recently developed Source Finder (SoFi) interface. Six factors were extracted including hydrocarbon-like OA (HOA), cooking-related OA (COA), biomass burning OA (BBOA), low-volatility oxygenated OA (LV-OOA), semivolatile oxygenated OA (SV-OOA), and nitrogen-enriched OA (NOA). The aerosol fraction that was attributed to BB factor was 9%, on average over the sampling period. The high proportion of oxygenated OA (72%), typically representing aged emissions, could possess a fraction of oxygenated species transfored from BB components on their way to the sampling site. PMID:27101459

  10. Characterization of ice-nucleating bacteria using on-line electron impact ionization aerosol mass spectrometry.

    Science.gov (United States)

    Wolf, R; Slowik, J G; Schaupp, C; Amato, P; Saathoff, H; Möhler, O; Prévôt, A S H; Baltensperger, U

    2015-04-01

    The mass spectral signatures of airborne bacteria were measured and analyzed in cloud simulation experiments at the AIDA (Aerosol Interaction and Dynamics in the Atmosphere) facility. Suspensions of cultured cells in pure water were sprayed into the aerosol and cloud chambers forming an aerosol which consisted of intact cells, cell fragments and residual particles from the agar medium in which the bacteria were cultured. The aerosol particles were analyzed with a high-resolution time-of-flight aerosol mass spectrometer equipped with a newly developed PM2.5 aerodynamic lens. Positive matrix factorization (PMF) using the multilinear engine (ME-2) source apportionment was applied to deconvolve the bacteria and agar mass spectral signatures. The bacteria mass fraction contributed between 75 and 95% depending on the aerosol generation, with the remaining mass attributed to agar. We present mass spectra of Pseudomonas syringae and Pseudomonas fluorescens bacteria typical for ice-nucleation active bacteria in the atmosphere to facilitate the distinction of airborne bacteria from other constituents in ambient aerosol, e.g. by PMF/ME-2 source apportionment analyses. Nitrogen-containing ions were the most salient feature of the bacteria mass spectra, and a combination of C4 H8 N(+) (m/z 70) and C5 H12 N(+) (m/z 86) may be used as marker ions. PMID:26149110

  11. Comparative evaluation of essential and toxic elements in the blood of kidney failure patients and healthy referents.

    Science.gov (United States)

    Panhwar, Abdul Haleem; Kazi, Tasneem Gul; Afridi, Hassan Imran; Arain, Salma Aslam; Arain, Mariam S; Brahman, Kapil Dev; Ullah, Naeem; Ali, Jamshed; Arain, Sadaf Sadia

    2015-02-01

    The aim of the present study was to evaluate the comparative distribution, correlation, and apportionment of selected elements-aluminum (Al), calcium (Ca), cadmium (Cd), potassium (K), magnesium (Mg), sodium (Na), and lead (Pb)-in the blood samples of male kidney failure patients (KFP) and healthy subjects of age ranged 30-60 years. The blood samples were digested with nitric acid and perchloric acid mixture (2:1), followed by the quantification of elements by atomic absorption spectrometry. The concentration of essential elements in blood samples of KFP were found in the range of Ca (97-125), Mg (18-36), Na (2971-3685), and K (177-270) mg/L while, the levels of Al, Cd, and Pb were found in the range of (475-1275), (0.9-9.9), and (211-623) μg/L, respectively. In the healthy referents, concentration of electrolytes in blood samples was lower than KFP, but difference was not significant (p > 0.05). While the levels of toxic elements in blood samples of referents were three- to sixfold lower than KFP (p < 0.01). Principal component analysis (PCA) and cluster analysis (CA) of the element data manifested diverse apportionment of the selected elements in the blood sample of the KFP compared with the healthy counterparts. PMID:25632899

  12. Nuclear magnetic resonance spectroscopy for determining the functional content of organic aerosols: A review

    International Nuclear Information System (INIS)

    The knowledge deficit of organic aerosol (OA) composition has been identified as the most important factor limiting our understanding of the atmospheric fate and implications of aerosol. The efforts to chemically characterize OA include the increasing utilization of nuclear magnetic resonance spectroscopy (NMR). Since 1998, the functional composition of different types, sizes and fractions of OA has been studied with one-dimensional, two-dimensional and solid state proton and carbon-13 NMR. This led to the use of functional group ratios to reconcile the most important sources of OA, including secondary organic aerosol and initial source apportionment using positive matrix factorization. Future research efforts may be directed towards the optimization of experimental parameters, detailed NMR experiments and analysis by pattern recognition methods to identify the chemical components, determination of the NMR fingerprints of OA sources and solid state NMR to study the content of OA as a whole. - Highlights: • Organic aerosol composition by 1H- and 13C-NMR spectroscopy. • NMR fingerprints of specific sources, types and sizes of organic aerosol. • Source reconciliation and apportionment using NMR spectroscopy. • Research priorities towards understanding organic aerosol composition and origin. - This review presents the recent advances on the characterization of organic aerosol composition using nuclear magnetic resonance spectroscopy

  13. Organic tracer-based source analysis of PM2.5 organic and elemental carbon: A case study at Dongguan in the Pearl River Delta, China

    Science.gov (United States)

    Wang, Qiong Qiong; Huang, X. H. Hilda; Zhang, Ting; Zhang, Qingyan; Feng, Yongming; Yuan, Zibing; Wu, Dui; Lau, Alexis K. H.; Yu, Jian Zhen

    2015-10-01

    Organic carbon (OC) and elemental carbon (EC) are major constituents of PM2.5 and their source apportionment remains a challenging task due to the great diversity of their sources and lack of source-specific tracer data. In this work, sources of OC and EC are investigated using positive matrix factorization (PMF) analysis of PM2.5 chemical composition data, including major ions, OC, EC, elements, and organic molecular source markers, for a set of 156 filter samples collected over three years from 2010 to 2012 at Dongguan in the Pearl River Delta, China. The key organic tracers include levoglucosan, mannosan, hopanes, C27-C33n-alkanes, and polycyclic aromatic hydrocarbons (PAHs). Using these species as input for the PMF model, nine factors were resolved. Among them, biomass burning and coal combustion were significant sources contributing 15-17% of OC and 24-30% and 34-35% of EC, respectively. Industrial emissions and ship emissions, identified through their characteristic metal signatures, contributed 16-24% and 7-8% of OC and 8-11% and 16-17% of EC, respectively. Vehicle exhaust was a less significant source, accounting for 3-4% of OC and 5-8% of EC. Secondary OC, taken to be the sum of OC present in secondary sulfate and nitrate formation source factors, made up 27-36% of OC. Plastic burning, identified through 1,3,5-triphenylbenzene as a tracer, was a less important source for OC(≤4%) and EC (5-10%), but a significant source for PAHs at this site. The utility of organic source tracers was demonstrated by comparing PMF runs with different combinations of organic tracers removed from the input species list. Levoglucosan and mannosan were important additions to distinguish biomass burning from coal combustion by reducing collinearity among source profiles. Inclusion of hopanes and 1,3,5-triphenylbenzene was found to be necessary in resolving the less significant sources vehicle exhaust and plastic burning. Inclusion of C27-C33n-alkanes and PAHs can influence the

  14. Investigating sources and pathways of perfluoroalkyl acids (PFAAs) in aquifers in Tokyo using multiple tracers

    International Nuclear Information System (INIS)

    We employed a multi-tracer approach to investigate sources and pathways of perfluoroalkyl acids (PFAAs) in urban groundwater, based on 53 groundwater samples taken from confined aquifers and unconfined aquifers in Tokyo. While the median concentrations of groundwater PFAAs were several ng/L, the maximum concentrations of perfluorooctane sulfonate (PFOS, 990 ng/L), perfluorooctanoate (PFOA, 1800 ng/L) and perfluorononanoate (PFNA, 620 ng/L) in groundwater were several times higher than those of wastewater and street runoff reported in the literature. PFAAs were more frequently detected than sewage tracers (carbamazepine and crotamiton), presumably owing to the higher persistence of PFAAs, the multiple sources of PFAAs beyond sewage (e.g., surface runoff, point sources) and the formation of PFAAs from their precursors. Use of multiple methods of source apportionment including principal component analysis–multiple linear regression (PCA–MLR) and perfluoroalkyl carboxylic acid ratio analysis highlighted sewage and point sources as the primary sources of PFAAs in the most severely polluted groundwater samples, with street runoff being a minor source (44.6% sewage, 45.7% point sources and 9.7% street runoff, by PCA–MLR). Tritium analysis indicated that, while young groundwater (recharged during or after the 1970s, when PFAAs were already in commercial use) in shallow aquifers (< 50 m depth) was naturally highly vulnerable to PFAA pollution, PFAAs were also found in old groundwater (recharged before the 1950s, when PFAAs were not in use) in deep aquifers (50–500 m depth). This study demonstrated the utility of multiple uses of tracers (pharmaceuticals and personal care products; PPCPs, tritium) and source apportionment methods in investigating sources and pathways of PFAAs in multiple aquifer systems. - Highlights: • Aquifers in Tokyo had high levels of perfluoroalkyl acids (up to 1800 ng/L). • PFAAs were more frequently detected than sewage

  15. Quantifying impacts on air quality of vehicular emissions in Sao Paulo and Rio de Janeiro

    Science.gov (United States)

    Artaxo, Paulo; Ferreira de Brito, Joel; Godoy, José Marcus; Luiza Godoy, Maria; Junior, Djacinto

    2016-04-01

    Vehicular emissions in megacities such as Sao Paulo and Rio de Janeiro are increasingly becoming a global issue. The São Paulo Metropolitan Area (SPMA), located in Southeast of Brazil, is a megacity with a population of 18 million people, with 7 million cars and large-scale industrial emissions. Rio de Janeiro is also a large city with different meteorology than São Paulo. All cars in Brazil runs gasohol, with 23% ethanol in gasoline, and for the last 10 years, flex cars that can run on gasohol, ethanol or any mixture dominate the market. Overall ethanol accounts for about 30-40% of fuel burned in both cities. To improve the understanding of vehicular emission impacts on aerosol composition and life cycle in these two large megacities a source apportionment study, combining online and offline measurements, was performed. Aerosols were collected for one year to capture seasonal variability at 4 sites in each city, with inorganic and organic aerosol component being sampled. Organic and elemental carbon were measured using a Sunset Laboratory Dual Optics (transmission and reflectance) Carbon Analyzer and about 22 trace elements has been measured using polarized X-Ray Fluorescence (XRF). Aerosol mass and black carbon were also measured, as well as trace gases to help in aerosol source apportionment. In Sao Paulo, the average PM2.5 mass concentration obtained varied from 9.6 to 12.2 μg m-3 for the several sites, and similar concentrations were measured in Rio de Janeiro. At all sites, organic matter (OM) has dominated fine mode aerosol concentration with 42 to 60% of the aerosol mass. EC accounted for 21 to 31% of fine mode aerosol mass concentration. Sulfate accounted for 21 to 26% of PM2.5 for the sites. Aerosol source apportionment was done with receptor analysis and integration with online data such as PTR-MS, Aethalometers, Nephelometers and ACSM helped to apportion vehicular emissions. For the 8 sites operated in Sao Paulo and Rio de Janeiro, vehicular

  16. Advanced Fine Particulate Characterization Methods

    Energy Technology Data Exchange (ETDEWEB)

    Steven Benson; Lingbu Kong; Alexander Azenkeng; Jason Laumb; Robert Jensen; Edwin Olson; Jill MacKenzie; A.M. Rokanuzzaman

    2007-01-31

    The characterization and control of emissions from combustion sources are of significant importance in improving local and regional air quality. Such emissions include fine particulate matter, organic carbon compounds, and NO{sub x} and SO{sub 2} gases, along with mercury and other toxic metals. This project involved four activities including Further Development of Analytical Techniques for PM{sub 10} and PM{sub 2.5} Characterization and Source Apportionment and Management, Organic Carbonaceous Particulate and Metal Speciation for Source Apportionment Studies, Quantum Modeling, and High-Potassium Carbon Production with Biomass-Coal Blending. The key accomplishments included the development of improved automated methods to characterize the inorganic and organic components particulate matter. The methods involved the use of scanning electron microscopy and x-ray microanalysis for the inorganic fraction and a combination of extractive methods combined with near-edge x-ray absorption fine structure to characterize the organic fraction. These methods have direction application for source apportionment studies of PM because they provide detailed inorganic analysis along with total organic and elemental carbon (OC/EC) quantification. Quantum modeling using density functional theory (DFT) calculations was used to further elucidate a recently developed mechanistic model for mercury speciation in coal combustion systems and interactions on activated carbon. Reaction energies, enthalpies, free energies and binding energies of Hg species to the prototype molecules were derived from the data obtained in these calculations. Bimolecular rate constants for the various elementary steps in the mechanism have been estimated using the hard-sphere collision theory approximation, and the results seem to indicate that extremely fast kinetics could be involved in these surface reactions. Activated carbon was produced from a blend of lignite coal from the Center Mine in North Dakota and

  17. Investigating sources and pathways of perfluoroalkyl acids (PFAAs) in aquifers in Tokyo using multiple tracers

    Energy Technology Data Exchange (ETDEWEB)

    Kuroda, Keisuke, E-mail: keisukekr@gmail.com [Department of Urban Engineering, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656 (Japan); Murakami, Michio [Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro, Tokyo 153-8505 (Japan); Oguma, Kumiko [Department of Urban Engineering, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656 (Japan); Takada, Hideshige [Laboratory of Organic Geochemistry (LOG), Institute of Symbiotic Science and Technology, Tokyo University of Agriculture and Technology, Fuchu, Tokyo 183-8509 (Japan); Takizawa, Satoshi [Department of Urban Engineering, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656 (Japan)

    2014-08-01

    We employed a multi-tracer approach to investigate sources and pathways of perfluoroalkyl acids (PFAAs) in urban groundwater, based on 53 groundwater samples taken from confined aquifers and unconfined aquifers in Tokyo. While the median concentrations of groundwater PFAAs were several ng/L, the maximum concentrations of perfluorooctane sulfonate (PFOS, 990 ng/L), perfluorooctanoate (PFOA, 1800 ng/L) and perfluorononanoate (PFNA, 620 ng/L) in groundwater were several times higher than those of wastewater and street runoff reported in the literature. PFAAs were more frequently detected than sewage tracers (carbamazepine and crotamiton), presumably owing to the higher persistence of PFAAs, the multiple sources of PFAAs beyond sewage (e.g., surface runoff, point sources) and the formation of PFAAs from their precursors. Use of multiple methods of source apportionment including principal component analysis–multiple linear regression (PCA–MLR) and perfluoroalkyl carboxylic acid ratio analysis highlighted sewage and point sources as the primary sources of PFAAs in the most severely polluted groundwater samples, with street runoff being a minor source (44.6% sewage, 45.7% point sources and 9.7% street runoff, by PCA–MLR). Tritium analysis indicated that, while young groundwater (recharged during or after the 1970s, when PFAAs were already in commercial use) in shallow aquifers (< 50 m depth) was naturally highly vulnerable to PFAA pollution, PFAAs were also found in old groundwater (recharged before the 1950s, when PFAAs were not in use) in deep aquifers (50–500 m depth). This study demonstrated the utility of multiple uses of tracers (pharmaceuticals and personal care products; PPCPs, tritium) and source apportionment methods in investigating sources and pathways of PFAAs in multiple aquifer systems. - Highlights: • Aquifers in Tokyo had high levels of perfluoroalkyl acids (up to 1800 ng/L). • PFAAs were more frequently detected than sewage

  18. Demonstration of the Applicability of Novel Photoacoustic Aerosol Monitor for Optical Absorption Coefficient Determination. Laboratory and Field Test.

    Science.gov (United States)

    Ajtai, T.; Schnaiter, M.; Linke, C.; Vragel, M.; Filep, Á.; Fődi, L.; Motika, G.; Bozóki, Z.; Szabó, G.

    2009-04-01

    Despite of its importance, the possibilities to determine the direct radiative forcing by atmospheric aerosols is very limited due to lack of the reliable on-line instruments. Therefore there is an increasing concern for novel methods promising more accurate and reliable results in this field. The accuracy and reliability of the available on-line instruments like SP2 (Single Particle Soot Photometer), MAAP (Multi Angle Absorption Photometer), are limited by the weakness of the spectral resolution or the sampling artefact of filter matrix during the light attenuation measurement on the deposited filter. These methods neither suitable for direct determination of the light absorption by aerosols nor dispose the capability of the source apportionment. In this work we present a novel photoacoustic based instrument for direct light absorption measurements in the atmosphere and demonstrate the suitability of that both in laboratory and field circumstances. We have developed a novel Multi Wavelength PhotoAcoustic System (WaSul-MuWaPas) based on the diode laser pumped, high repetition rate, Q-switched Nd:YAG laser and its frequency converted harmonics for direct determination of light absorption by aerosols. This instrument has designed to make in situ measurements at four different wavelengths simultaneously from the NIR to the UV wavelength range (1064nm, 532nm, 355nm, 266nm). The Wasul-MuWaPas measures directly the optical absorption coefficient on airborne particles, not belong to the integrated plate type technique (filter-free operation), operating at wide wavelength range (source apportionment possibilities), due to the possibilities of the wavelength independent cell constant determination the measurement method is absolute. Because of these the Wasul-MuWaPas system may become one of the best candidate for absorption measurements of various atmospheric aerosols such as black carbon, mineral dust, and secondary organic and inorganic aerosols as well as for source

  19. Connecting Organic Aerosol Climate-Relevant Properties to Chemical Mechanisms of Sources and Processing

    Energy Technology Data Exchange (ETDEWEB)

    Thornton, Joel

    2015-01-26

    The research conducted on this project aimed to improve our understanding of secondary organic aerosol (SOA) formation in the atmosphere, and how the properties of the SOA impact climate through its size, phase state, and optical properties. The goal of this project was to demonstrate that the use of molecular composition information to mechanistically connect source apportionment and climate properties can improve the physical basis for simulation of SOA formation and properties in climate models. The research involved developing and improving methods to provide online measurements of the molecular composition of SOA under atmospherically relevant conditions and to apply this technology to controlled simulation chamber experiments and field measurements. The science we have completed with the methodology will impact the simulation of aerosol particles in climate models.

  20. Physico-chemical characterisation of particulate heavy metals from municipal solid waste incinerator emissions and their contributions to ambient air quality. Case of Toulon MSWI (South of France); Caracterisation physico-chimique et tracage des emissions particulaires metalliques d'une usine d'incineration d'ordures menageres dans l'air ambiant. Exemple de l'UIOM de Toulon (Var, France)

    Energy Technology Data Exchange (ETDEWEB)

    Le Floch, M

    2004-07-15

    The aims of this study are the physico-chemical characterisation, the apportionment and the following of particulate heavy metals from MSWI emissions. Various methods (in situ data treatment, unmixing models and codes, UNMIX or CMB, sequential extractions and extended X-ray absorption fine structure (EXAFS) agree in the following: - identification of the MSWI source in two profiles (Zn - Ca and Ba - Cu - Fe - Zn - Pb - Ca); - estimation of its contribution of up to 25% of the total sources contribution; - showing the seasonal variability in term of profile and contribution of this source; - suggest the potential of emitted elements to enter the food chain; This EXAFS first approach on atmospheric particulate matter shows that zinc and lead are in an atomic environment with calcium, silicon and aluminum. In spite of disputable conclusions, isotopic lead ratios define a 'MSWI' end-member and confirm that the town-center of Toulon is outside the MSWI plume influence. (author)

  1. Spiers Memorial Lecture. Introductory lecture: chemistry in the urban atmosphere.

    Science.gov (United States)

    Baltensperger, Urs

    2016-07-18

    The urban atmosphere is characterised by a multitude of complex processes. Gaseous and particulate components are continuously emitted into the atmosphere from many different sources. These components are then dispersed in the urban atmosphere via turbulent mixing. Numerous chemical reactions modify the gas phase chemistry on multiple time scales, producing secondary pollutants. Through partitioning, the chemical and physical properties of the aerosol particles are also constantly changing as a consequence of dispersion and gas phase chemistry. This review presents an overview of the involved processes, focusing on the contributions presented at this conference and putting them into a broader context. Advanced methods for aerosol source apportionment are presented as well, followed by some aspects of health effects related to air pollution. PMID:27247983

  2. Strategic analysis of a water rights conflict in the south western United States.

    Science.gov (United States)

    Philpot, Simone; Hipel, Keith; Johnson, Peter

    2016-09-15

    A strategic analysis of the ongoing conflict between Nevada and Utah, over groundwater allocation at Snake Valley, is carried out in order to investigate ways on how to resolve this dispute. More specifically, the Graph Model for Conflict Resolution is employed to formally model and analyze this conflict using the decision support system called GMCR+. The conflict analysis findings indicate that the dispute is enduring because of a lack of incentive and opportunity for any party to move beyond the present circumstances. Continued negotiations are not likely to resolve this conflict. A substantial change in the preferences or options of the disputants, or new governance tools will be required to move this conflict forward. This may hold lessons for future groundwater conflicts. It is, however, increasingly likely that the parties will require a third party intervention, such as equal apportionment by the US Supreme Court. PMID:27235804

  3. Projected impacts of climate change on farmers' extraction of groundwater from crystalline aquifers in South India.

    Science.gov (United States)

    Ferrant, Sylvain; Caballero, Yvan; Perrin, Jérome; Gascoin, Simon; Dewandel, Benoit; Aulong, Stéphanie; Dazin, Fabrice; Ahmed, Shakeel; Maréchal, Jean-Christophe

    2014-01-01

    Local groundwater levels in South India are falling alarmingly. In the semi-arid crystalline Deccan plateau area, agricultural production relies on groundwater resources. Downscaled Global Climate Model (GCM) data are used to force a spatially distributed agro-hydrological model in order to evaluate Climate Change (CC) effects on local groundwater extraction (GWE). The slight increase of precipitation may alleviate current groundwater depletion on average, despite the increased evaporation due to warming. Nevertheless, projected climatic extremes create worse GWE shortages than for present climate. Local conditions may lead to opposing impacts on GWE, from increases to decreases (+/-20 mm/year), for a given spatially homogeneous CC forcing. Areas vulnerable to CC in terms of irrigation apportionment are thus identified. Our results emphasize the importance of accounting for local characteristics (water harvesting systems and maximal aquifer capacity versus GWE) in developing measures to cope with CC impacts in the South Indian region.

  4. Conference particulate matter and indoor environment, I.N.E.R.I.S.; Particulate matter and indoor environment

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    Comprehensive characterisation of indoor and outdoor air as well as pollution emission sources Integrated health and environmental risk assessment Scientific and technical basis for airborne pollution management and control Fine and coarse particles. The sources of indoor air pollution are originate separately, are transported separately, are removed from atmosphere by different mechanisms, have different optical properties, have different chemical properties, require different control techniques. for the health effects due to particles, they decrease the lung function, increase respiratory symptoms, increase chronic obstructive pulmonary diseases, increased cardiovascular disease, increased mortality. The different sources contributing to the highest concentrations are: concentrations: tobacco smoking, cooking, vacuuming, dusting and sweeping, heaters, stoves, fireplaces and some other non identified sources. In the future we want more focus on fine and ultra fine particles, investigate source apportionment of particles, better understanding and quantification of exposure, to implement guidelines for particle concentration in indoor air and find better cleaning technologies. (N.C.)

  5. The effect of Brown Carbon on thermal-optical analysis: a correction based on optical multi-wavelength analysis

    Science.gov (United States)

    Dario, Massabò; Lorenzo, Caponi; Chiara, Bove Maria; Paolo, Prati

    2016-04-01

    Carbonaceous aerosol (CA) has an important impact on air quality, human health and climate change. Total Carbon (TC) is generally divided in organic carbon (OC) and elemental carbon (EC) (although a minor fraction of carbonate carbon (CC) may be present). This classification is based on their thermo-optical properties: while EC is strongly light absorbing, OC is generally transparent in the visible range except for some particular compounds. In fact, another fraction of light-absorbing organic carbon exists which is not black and is generally called brown carbon (BrC) (Andreae and Gelencsér, 2006). We recently introduced a new method to apportion the absorption coefficient (babs) of carbonaceous atmospheric aerosols starting from multi-wavelength optical analysis (Massabò et al., 2015). This analysis is performed by the MWAA, an instrument developed at the Physics Department of University of Genoa (Massabò et al., 2013) able to measure the aerosol absorption coefficient at 5 different wavelengths ranging from UV to IR. The method is based on the information gathered at these five different wavelengths, in a renewed and upgraded version of the approach usually referred to as Aethalometer model (Sandradewi et al., 2008). The resulting optical apportionment provides the quantification of EC and, with some assumptions, also of OC coming from fossil fuels and wood burning. Thermal-optical methods are presently the most widespread approach to OC/EC speciation. Despite their popularity, there is still a disagreement among the results, especially for what concerns EC as different thermal protocols can be used. In fact, the pyrolysis occurring during the analysis can heavily affect OC/EC separation, depending on PM composition in addition to the used protocol. Furthermore, the presence in the sample of BrC can shift the split point since it is light absorbing also @ 635nm, the typical laser wavelength used in this technique (Chen et al., 2015). We present here the

  6. Emission factors of carbonaceous particulate matter and polycyclic aromatic hydrocarbons from residential solid fuel combustions

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Guofeng [Jiangsu Academy of Environmental Science, Nanjing (China). Inst. of Atmospheric Sciences

    2014-07-01

    Emission inventory is basic for the understanding of environmental behaviors and potential effects of compounds, however, current inventories are often associated with relatively high uncertainties. One important reason is the lack of emission factors, especially for the residential solid fuel combustion in developing countries. In the present study, emission factors of a group of pollutants including particulate matter, organic carbon, elemental carbon (sometimes known as black carbon) and polycyclic aromatic hydrocarbons were measured for a variety of residential solid fuels including coal, crop straw, wood, and biomass pellets in rural China. The study provided a large number of emission factors that can be further used in emission estimation. Composition profiles and isomer ratios were investigated and compared so as to be used in source apportionment. In addition, the present study identified and quantified the influence of factors like fuel moisture, volatile matter on emission performance.

  7. THE USE OF CALCULATION OF COSTS FOR ACTIVITIES TO IMPROVE COST MANAGEMENT AND PROFITABILITY

    Directory of Open Access Journals (Sweden)

    BUŞAN GABRIELA

    2012-11-01

    Full Text Available Dissatisfaction with the classical systems of managerial accounting has led to global acceptance of the ABC, as a result of the many theoretical and applied works, which had as its objective the creation of a system for calculating relevant costs, adapted to the needs of information, in the new context of production organization. Under this method, the task, allowing a new vision in the company and cut cross vision, becomes the Centre of representation and modeling of enterprise and serves as an interface between the resources consumed and cost bearers whose cost you want to measure it. In this way you get a real cost, on the basis of which the strategic decisions by removing non-creative activities and using as the basis for apportionment of costs it generates activity.

  8. Weathering of Pisha-Sandstones in the Wind-Water Erosion Crisscross Region on the Loess Plateau

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Two types of pisha-sandstones of purple sandstones and gray sandstones, widely distributing in the wind-water erosion crisscross region of China, were selected and used in laboratory experiments