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Sample records for analytical source-apportionment methods

  1. PM2.5 water-soluble elements in the southeastern United States: automated analytical method development, spatiotemporal distributions, source apportionment, and implications for heath studies

    Science.gov (United States)

    Fang, T.; Guo, H.; Verma, V.; Peltier, R. E.; Weber, R. J.

    2015-10-01

    Water-soluble redox-active metals are potentially toxic due to its ability to catalytically generate reactive oxygen species (ROS) in vivo, leading to oxidative stress. As part of the Southeastern Center for Air Pollution and Epidemiology (SCAPE), we developed a method to quantify water-soluble elements, including redox-active metals, from a large number of filter samples (N = 530) in support of the center's health studies. PM2.5 samples were collected during 2012-2013 at various sites (three urban, two rural, a near-road site, and a road-side site) in the southeastern United States, using high-volume samplers. Water-soluble elements (S, K, Ca, Ti, Mn, Fe, Cu, Zn, As, Se, Br, Sr, Ba, and Pb) were determined by extracting filters in deionized water and re-aerosolized for analyses by X-ray fluorescence (XRF) using an online aerosol element analyzer (Xact, Cooper Environmental). Concentrations ranged from detection limits (nominally 0.1 to 30 ng m-3) to 1.2 μg m-3, with S as the most abundant element, followed by Ca, K, Fe, Cu, Zn, and Ba. Positive matrix factorization (PMF) identified four factors that were associated with specific sources based on relative loadings of various tracers. These include brake/tire wear (with tracers Ba and Cu), biomass burning (K), secondary formation (S, Se, and WSOC), and mineral dust (Ca). Of the four potentially toxic and relatively abundant metals (redox-active Cu, Mn, Fe, and redox-inactive Zn), 51 % of Cu, 32 % of Fe, 17 % of Mn, and 45 % of Zn were associated with the brake/tire factor. Mn was mostly associated with the mineral dust factor (45 %). Zn was found in a mixture of factors, with 26 % associated with mineral dust, 14 % biomass burning, and 13 % secondary formation. Roughly 50 % of Fe and 40 % of Cu were apportioned to the secondary formation factor, likely through increases in the soluble fraction of these elements by sulfur-driven aerosol water and acidity. Linkages between sulfate and water-soluble Fe and Cu may

  2. Comparison of several wood smoke markers and source apportionment methods for wood burning particulate mass

    OpenAIRE

    Sandradewi, J.; Prévôt, A.S.H.; M. R. Alfarra; Szidat, S.; Wehrli, M. N.; Ruff, M.; S. Weimer; Lanz, V A; Weingartner, E.; Perron, N.; Caseiro, A.; Kasper-Giebl, A.; H. Puxbaum; Wacker, L.; Baltensperger, U.

    2008-01-01

    Residential wood combustion has only recently been recognized as a major contributor to air pollution in Switzerland and in other European countries. A source apportionment method using the aethalometer light absorption parameters was applied to five winter campaigns at three sites in Switzerland: a village with high wood combustion activity in winter, an urban background site and a highway site. The particulate mass from traffic (PMtraffic) and wood burning (PM

  3. Ensemble-trained source apportionment of fine particulate matter and method uncertainty analysis

    Science.gov (United States)

    Balachandran, Sivaraman; Pachon, Jorge E.; Hu, Yongtao; Lee, Dongho; Mulholland, James A.; Russell, Armistead G.

    2012-12-01

    An ensemble-based approach is applied to better estimate source impacts on fine particulate matter (PM2.5) and quantify uncertainties in various source apportionment (SA) methods. The approach combines source impacts from applications of four individual SA methods: three receptor-based models and one chemical transport model (CTM). Receptor models used are the chemical mass balance methods CMB-LGO (Chemical Mass Balance-Lipschitz global optimizer) and CMB-MM (molecular markers) as well as a factor analytic method, Positive Matrix Factorization (PMF). The CTM used is the Community Multiscale Air Quality (CMAQ) model. New source impact estimates and uncertainties in these estimates are calculated in a two-step process. First, an ensemble average is calculated for each source category using results from applying the four individual SA methods. The root mean square error (RMSE) between each method with respect to the average is calculated for each source category; the RMSE is then taken to be the updated uncertainty for each individual SA method. Second, these new uncertainties are used to re-estimate ensemble source impacts and uncertainties. The approach is applied to data from daily PM2.5 measurements at the Atlanta, GA, Jefferson Street (JST) site in July 2001 and January 2002. The procedure provides updated uncertainties for the individual SA methods that are calculated in a consistent way across methods. Overall, the ensemble has lower relative uncertainties as compared to the individual SA methods. Calculated CMB-LGO uncertainties tend to decrease from initial estimates, while PMF and CMB-MM uncertainties increase. Estimated CMAQ source impact uncertainties are comparable to other SA methods for gasoline vehicles and SOC but are larger than other methods for other sources. In addition to providing improved estimates of source impact uncertainties, the ensemble estimates do not have unrealistic extremes as compared to individual SA methods and avoids zero impact

  4. Comparison of several wood smoke markers and source apportionment methods for wood burning particulate mass

    Directory of Open Access Journals (Sweden)

    J. Sandradewi

    2008-04-01

    Full Text Available Residential wood combustion has only recently been recognized as a major contributor to air pollution in Switzerland and in other European countries. A source apportionment method using the aethalometer light absorption parameters was applied to five winter campaigns at three sites in Switzerland: a village with high wood combustion activity in winter, an urban background site and a highway site. The particulate mass from traffic (PMtraffic and wood burning (PMwb emissions obtained with this model compared fairly well with results from the 14C source apportionment method. PMwb from the model was also compared to well known wood smoke markers such as anhydrosugars (levoglucosan and mannosan and fine mode potassium, as well as to a marker recently suggested from the Aerodyne aerosol mass spectrometer (mass fragment m/z 60. Additionally the anhydrosugars were compared to the 14C results and were shown to be comparable to literature values from wood burning emission studies using different types of wood (hardwood, softwood. The levoglucosan to PMwb ratios varied much more strongly between the different campaigns (4–13% compared to mannosan to PMwb with a range of 1–1.5%. Possible uncertainty aspects for the various methods and markers are discussed.

  5. A study of control policy in the Pearl River Delta region by using the particulate matter source apportionment method

    Science.gov (United States)

    Wu, Dongwei; Fung, Jimmy Chi Hung; Yao, Teng; Lau, Alexis Kai Hon

    2013-09-01

    In recent years, Mainland China, and in particular the industrial hotbed of the Pearl River Delta (PRD) has experienced an increasingly serious problem of high concentrations of airborne particulate matter. Following the tightening-up of China's air quality policies in recent years, and with especially fine particles now added to a new air quality objective, the identification of major source regions and major types of pollutants has become crucial. In this study, the Comprehensive Air Quality Model (CAMx), together with the Particulate Source Apportionment Technology (PSAT) source apportionment method, has been applied to analyze how different emission activities influence PM concentration in the PRD region. By using this method, a detailed source region and emission category contribution matrix is derived for all regions within the Hong Kong/PRD region and source appointment results show that, on average, for different cities super-regional transport and mobile vehicles are the two major fine particle sources, contributing 62% (34.3 μg m-3) and 21% (12.2 μg m-3) of the total figure in December, and 42% (13.1 μg m-3) and 28% (9.7 μg m-3) in April. Meanwhile, over the same period in Hong Kong, in addition to these two factors, marine proved another very significant source of particle pollutant, amounting to 18% of the total figure (4.7 μg m-3). Another important cause of high PM levels has been the transport of fine particles between cities within the PRD region, with three different regions selected for detailed analysis. Results show that for the Hong Kong/PRD region local reduction of mobile sources and collaboration between different areas could have succeeded in alleviating the air pollution problem.

  6. 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.

  7. Path-integral method for the source apportionment of photochemical pollutants

    Science.gov (United States)

    Dunker, A. M.

    2015-06-01

    A new, path-integral method is presented for apportioning the concentrations of pollutants predicted by a photochemical model to emissions from different sources. A novel feature of the method is that it can apportion the difference in a species concentration between two simulations. For example, the anthropogenic ozone increment, which is the difference between a simulation with all emissions present and another simulation with only the background (e.g., biogenic) emissions included, can be allocated to the anthropogenic emission sources. The method is based on an existing, exact mathematical equation. This equation is applied to relate the concentration difference between simulations to line or path integrals of first-order sensitivity coefficients. The sensitivities describe the effects of changing the emissions and are accurately calculated by the decoupled direct method. The path represents a continuous variation of emissions between the two simulations, and each path can be viewed as a separate emission-control strategy. The method does not require auxiliary assumptions, e.g., whether ozone formation is limited by the availability of volatile organic compounds (VOCs) or nitrogen oxides (NOx), and can be used for all the species predicted by the model. A simplified configuration of the Comprehensive Air Quality Model with Extensions (CAMx) is used to evaluate the accuracy of different numerical integration procedures and the dependence of the source contributions on the path. A Gauss-Legendre formula using three or four points along the path gives good accuracy for apportioning the anthropogenic increments of ozone, nitrogen dioxide, formaldehyde, and nitric acid. Source contributions to these increments were obtained for paths representing proportional control of all anthropogenic emissions together, control of NOx emissions before VOC emissions, and control of VOC emissions before NOx emissions. There are similarities in the source contributions from the

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

    International Nuclear Information System (INIS)

    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%). - Highlights: • Fingerprint variability poses challenges in PAH source apportionment analysis. • PCA can be used to group compounds or cluster measurements. • PMF requires results validation but is useful for source suggestion. • Bayesian CMB provide practical and credible solution. - A Bayesian CMB model combined with PMF is a practical and credible fingerprints based PAH source apportionment method

  10. 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

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

    Science.gov (United States)

    Kwok, R. H. F.; Baker, K. R.; Napelenok, S. L.; Tonnesen, G. S.

    2014-09-01

    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 be accounted

  12. 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.

  13. 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.

  14. 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

  15. 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)

  16. 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)

  17. 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.

  18. 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.

  19. 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.

  20. Characterization and source apportionment of organic aerosol using offline aerosol mass spectrometry

    Directory of Open Access Journals (Sweden)

    K. R. Daellenbach

    2015-08-01

    Full Text Available Field deployments of the Aerodyne Aerosol Mass Spectrometer (AMS have significantly advanced real-time measurements and source apportionment of non-refractory particulate matter. However, the cost and complex maintenance requirements of the AMS make impractical its deployment at sufficient sites to determine regional characteristics. Furthermore, the negligible transmission efficiency of the AMS inlet for supermicron particles significantly limits the characterization of their chemical nature and contributing sources. In this study, we utilize the AMS to characterize the water-soluble organic fingerprint of ambient particles collected onto conventional quartz filters, which are routinely sampled at many air quality sites. The method was applied to 256 particulate matter (PM filter samples (PM1, PM2.5, PM10 collected at 16 urban and rural sites during summer and winter. We show that the results obtained by the present technique compare well with those from co-located online measurements, e.g. AMS or Aerosol Chemical Speciation Monitor (ACSM. The bulk recoveries of organic aerosol (60–91 % achieved using this technique, together with low detection limits (0.8 μg of organic aerosol on the analyzed filter fraction allow its application to environmental samples. We will discuss the recovery variability of individual hydrocarbon, oxygen containing and other ions. The performance of such data in source apportionment is assessed in comparison to ACSM data. Recoveries of organic components related to different sources as traffic, wood burning and secondary organic aerosol are presented. This technique, while subjected to the limitations inherent to filter-based measurements (e.g. filter artifacts and limited time resolution may be used to enhance the AMS capabilities in measuring size-fractionated, spatially-resolved long-term datasets.

  1. Characterization and source apportionment of organic aerosol using offline aerosol mass spectrometry

    Science.gov (United States)

    Daellenbach, K. R.; Bozzetti, C.; Křepelová, A.; Canonaco, F.; Wolf, R.; Zotter, P.; Fermo, P.; Crippa, M.; Slowik, J. G.; Sosedova, Y.; Zhang, Y.; Huang, R.-J.; Poulain, L.; Szidat, S.; Baltensperger, U.; El Haddad, I.; Prévôt, A. S. H.

    2016-01-01

    Field deployments of the Aerodyne Aerosol Mass Spectrometer (AMS) have significantly advanced real-time measurements and source apportionment of non-refractory particulate matter. However, the cost and complex maintenance requirements of the AMS make its deployment at sufficient sites to determine regional characteristics impractical. Furthermore, the negligible transmission efficiency of the AMS inlet for supermicron particles significantly limits the characterization of their chemical nature and contributing sources. In this study, we utilize the AMS to characterize the water-soluble organic fingerprint of ambient particles collected onto conventional quartz filters, which are routinely sampled at many air quality sites. The method was applied to 256 particulate matter (PM) filter samples (PM1, PM2.5, and PM10, i.e., PM with aerodynamic diameters smaller than 1, 2.5, and 10 µm, respectively), collected at 16 urban and rural sites during summer and winter. We show that the results obtained by the present technique compare well with those from co-located online measurements, e.g., AMS or Aerosol Chemical Speciation Monitor (ACSM). The bulk recoveries of organic aerosol (60-91 %) achieved using this technique, together with low detection limits (0.8 µg of organic aerosol on the analyzed filter fraction) allow its application to environmental samples. We will discuss the recovery variability of individual hydrocarbon ions, ions containing oxygen, and other ions. The performance of such data in source apportionment is assessed in comparison to ACSM data. Recoveries of organic components related to different sources as traffic, wood burning, and secondary organic aerosol are presented. This technique, while subjected to the limitations inherent to filter-based measurements (e.g., filter artifacts and limited time resolution) may be used to enhance the AMS capabilities in measuring size-fractionated, spatially resolved long-term data sets.

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

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Liping; Han, Jiangpei; Xue, Jianlong; Zeng, Lingzao [College of Environmental and Natural Resource Sciences, Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition, Zhejiang University, Hangzhou, 310058 (China); Shi, Jiachun, E-mail: jcshi@zju.edu.cn [College of Environmental and Natural Resource Sciences, Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition, Zhejiang University, Hangzhou, 310058 (China); Wu, Laosheng, E-mail: laowu@zju.edu.cn [College of Environmental and Natural Resource Sciences, Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition, Zhejiang University, Hangzhou, 310058 (China); Jiang, Yonghai [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012 (China)

    2013-10-01

    Nitrate (NO{sub 3}{sup −}) 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 NO{sub 3}{sup −} concentration in water was in May (wet season, mean ± SD = 17.45 ± 9.50 mg L{sup −1}) and the lowest concentration occurred in December (dry season, mean ± SD = 10.54 ± 6.28 mg L{sup −1}). Nevertheless, no water sample in the study area exceeds the WHO drinking water limit of 50 mg L{sup −1} NO{sub 3}{sup −}. Four sources of NO{sub 3}{sup −} (atmospheric deposition, AD; soil N, SN; synthetic fertilizer, SF; manure and sewage, M and S) were identified using both hydrochemical characteristics [Cl{sup −}, NO{sub 3}{sup −}, HCO{sub 3}{sup −}, SO{sub 4}{sup 2−}, Ca{sup 2+}, K{sup +}, Mg{sup 2+}, Na{sup +}, dissolved oxygen (DO)] and dual isotope approach (δ{sup 15}N–NO{sub 3}{sup −} and δ{sup 18}O–NO{sub 3}{sup −}). 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 NO{sub 3}{sup −} 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 NO{sub 3}{sup −}, better

  3. 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

  4. 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).

  5. 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

  6. 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.

  7. Source apportionment of traffic emissions of particulate matter using tunnel measurements

    Science.gov (United States)

    Lawrence, Samantha; Sokhi, Ranjeet; Ravindra, Khaiwal; Mao, Hongjun; Prain, Hunter Douglas; Bull, Ian D.

    2013-10-01

    This study aims to quantify exhaust/non-exhaust emissions and the uncertainties associated with them by combining innovative motorway tunnel sampling and source apportionment modelling. Analytical techniques ICP-AES and GC-MS were used to identify the metallic and organic composition of PM10, respectively. Good correlation was observed between Fe, Cu, Mn, Ni, Pb and Sb and change in traffic volume. The concentration of polycyclic aromatic hydrocarbons and other organics varies significantly at the entrance and exit site of the tunnel, with fluoranthene, pyrene, benzo[a]pyrene, chrysene and benzothiazole having the highest incremented concentrations. The application of Principal Component Analysis and Multiple Linear Regression Analysis helped to identify the emission sources for 82% of the total PM10 mass inside the tunnel. Identified sources include resuspension (27%), diesel exhaust emissions (21%), petrol exhaust emissions (12%), brake wear emissions (11%) and road surface wear (11%). This study shows that major health related chemical species of PM10 originate from non-exhaust sources, further signifying the need for legislation to reduce these emissions.

  8. 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

  9. Characterization and source apportionment of organic aerosol using offline aerosol mass spectrometry

    OpenAIRE

    Daellenbach, K. R.; Bozzetti, C.; A. Křepelová; F. Canonaco; Wolf, R.; P. Zotter; P. Fermo; Crippa, M.; Slowik, J. G.; Y. Sosedova; Y. Zhang; R.-J. Huang; L. Poulain; S. Szidat; U. Baltensperger

    2015-01-01

    Field deployments of the Aerodyne Aerosol Mass Spectrometer (AMS) have significantly advanced real-time measurements and source apportionment of non-refractory particulate matter. However, the cost and complex maintenance requirements of the AMS make impractical its deployment at sufficient sites to determine regional characteristics. Furthermore, the negligible transmission efficiency of the AMS inlet for supermicron particles significantly limits the chara...

  10. Characterization and source apportionment of organic aerosol using offline aerosol mass spectrometry

    OpenAIRE

    Daellenbach, K. R.; Bozzetti, C.; A. Křepelová; F. Canonaco; Wolf, R.; P. Zotter; P. Fermo; Crippa, M.; Slowik, J. G.; Y. Sosedova; Y. Zhang; Huang, R.-J.; L. Poulain; S. Szidat; U. Baltensperger

    2016-01-01

    Field deployments of the Aerodyne Aerosol Mass Spectrometer (AMS) have significantly advanced real-time measurements and source apportionment of non-refractory particulate matter. However, the cost and complex maintenance requirements of the AMS make its deployment at sufficient sites to determine regional characteristics impractical. Furthermore, the negligible transmission efficiency of the AMS inlet for supermicron particles significantly limits the characterization of th...

  11. A new methodology to assess the performance and uncertainty of source apportionment models in intercomparison exercises

    Science.gov (United States)

    Belis, C. A.; Pernigotti, D.; Karagulian, F.; Pirovano, G.; Larsen, B. R.; Gerboles, M.; Hopke, P. K.

    2015-10-01

    A new methodology to assess source apportionment model performance in intercomparison exercises, encompassing the preparation of real-world and synthetic datasets and the evaluation of the source apportionment results reported by participants, is described. The evaluation consists of three types of tests: complementary tests, preliminary tests, and performance tests. The complementary tests provide summary information about the source apportionment results as a whole. The preliminary tests check whether source/factors belong to a given source category. Three types of indicators: Pearson correlation (Pearson), standardized identity distance (SID), and weighted difference (WD) are used to test factor/source chemical profiles, while factor/source time series and contribution-to-species values are tested only using the Pearson. The performance tests, based on international standards for proficiency testing, are targeted at evaluating whether the reported biases in the quantification of the factor/source contribution estimates (SCEs) and uncertainties are consistent with previously established quality standards in a fitness-for-purpose approach. Moreover, the consistency of the SCE time series is evaluated using a variant of the RMSE normalised by the reference standard uncertainty. The described methodology facilitates a thorough evaluation of the source apportionment output. The new indicator to compare source or factor profiles presented in this study (SID) is more robust and provides additional information compared to the existing ones.

  12. Source apportionment and the role of meteorological conditions in the assessment of air pollution exposure due to urban emissions

    Science.gov (United States)

    Schäfer, K.; Elsasser, M.; Arteaga-Salas, J. M.; Gu, J.; Pitz, M.; Schnelle-Kreis, J.; Cyrys, J.; Emeis, S.; Prevot, A. S. H.; Zimmermann, R.

    2014-01-01

    As particulate matter (PM) impacts human health, knowledge about its composition, exposure and source apportionment is required. A study of the urban atmosphere in the case of Augsburg, Germany, during winter (31 January-12 March 2010) is thus presented here. Investigations were performed on the basis of aerosol mass spectrometry and further air pollutants and meteorological measurements, including mixing layer height. Organic matter was separated by source apportionment of PM1 with positive matrix factorization (PMF) in three factors: OOA - oxygenated organic aerosol (secondary organic factor), HOA - hydrocarbon-like organic aerosol (traffic factor or primary organic factor) and WCOA - wood combustion organic aerosol (wood combustion factor), which extend the information from black carbon (BC) measurements. PMF was also applied to the particle size distribution (PSD) data of PM2.5 to determine different source profiles and we assigned them to the particle sources: nucleation aerosol, fresh traffic aerosol, aged traffic aerosol, stationary combustion aerosol and secondary aerosol. Ten different temporal phases were identified on the basis of weather characteristics and aerosol composition and used for correlations of all air pollutants and meteorological parameters. While source apportionment from both organic PM composition and PSD agree and show that the main emission sources of PM exposure are road traffic as well as stationary and wood combustion, secondary aerosol factor concentrations are very often the highest ones. The hierarchical clustering analysis with the Ward method of cross-correlations of each air pollutant and PM component and of the correlations of each pollutant with all meteorological parameters provided two clusters: "secondary pollutants of PM1 and fine particles" and "primary pollutants (including CO and benzene) and accumulation mode particles". The dominant meteorological influences on pollutant concentrations are wind speed and mixing

  13. Chemometric techniques in distribution, characterisation and source apportionment of polycyclic aromatic hydrocarbons (PAHS) in aquaculture sediments in Malaysia.

    Science.gov (United States)

    Retnam, Ananthy; Zakaria, Mohamad Pauzi; Juahir, Hafizan; Aris, Ahmad Zaharin; Zali, Munirah Abdul; Kasim, Mohd Fadhil

    2013-04-15

    This study investigated polycyclic aromatic hydrocarbons (PAHs) pollution in surface sediments within aquaculture areas in Peninsular Malaysia using chemometric techniques, forensics and univariate methods. The samples were analysed using soxhlet extraction, silica gel column clean-up and gas chromatography mass spectrometry. The total PAH concentrations ranged from 20 to 1841 ng/g with a mean of 363 ng/g dw. The application of chemometric techniques enabled clustering and discrimination of the aquaculture sediments into four groups according to the contamination levels. A combination of chemometric and molecular indices was used to identify the sources of PAHs, which could be attributed to vehicle emissions, oil combustion and biomass combustion. Source apportionment using absolute principle component scores-multiple linear regression showed that the main sources of PAHs are vehicle emissions 54%, oil 37% and biomass combustion 9%. Land-based pollution from vehicle emissions is the predominant contributor of PAHs in the aquaculture sediments of Peninsular Malaysia. PMID:23452623

  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

    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 contribution than the water-soluble OC (WSOC. Moreover, the experimental results demonstrate the lower refractivity of wood-burning EC compared to fossil EC and the difficulty of clearly isolating EC without premature evolution. Hence, simplified techniques of EC isolation for 14C analysis are prone to a substantial bias and generally tend towards an overestimation of fossil sources. To obtain the comprehensive picture of the sources of carbonaceous aerosols, the Swiss_4S protocol is not only implemented to measure OC and EC fractions, but also WINSOC as well as a continuum of refractory OC and non-refractory EC for 14C source apportionment. In addition, WSOC can be determined by subtraction of the water-soluble fraction of TC from untreated TC. Last, we recommend that 14C results of EC should in general be reported together with the EC recovery.

  16. 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.

  17. Radiocarbon (14C) source apportionment of carbonaceous aerosol components in the Asian Atmospheric Brown Cloud

    International Nuclear Information System (INIS)

    Full text: Light-absorbing carbonaceous matter constitutes one of the largest uncertainties in climate modeling. The high concentrations of black carbon - soot - in the Asian Brown Cloud lead to strong atmospheric heating and large surface cooling that is as important to regional climate forcing as greenhouse gases, yet the sources of these aerosols are not well understood. Emission inventory models suggest that biofuel/biomass burning accounts for 60 - 90 % of the sources of these aerosol components whereas measurements of the elemental composition of ambient aerosols compared with source signatures point to combustion of fossil fuel as the primary culprit. However, both approaches acknowledge large uncertainties in source apportionment of the elusively defined black carbon. This study approached the sourcing challenge by applying microscale radiocarbon measurements to aerosol particles collected during the winter monsoon both over the Indian Ocean and in central India. The radiocarbon approach is ideally suited to this task as fossil sources are void of 14C whereas biomass combustion products hold a contemporary 14C signal. High-volume air samples of total carbonaceous aerosols revealed 14C signals that were similar for N. Indian source and Indian Ocean receptor regions, consistent with the absence of any significant formation of secondary organic aerosols, with a 60 - 70 % contribution from biomass combustion and biogenic sources. Isolates of elemental or soot carbon fractions varied between 40 - 70 %, depending on isolation method. These novel radiocarbon constraints on the sources of light-absorbing carbonaceous matter aid prioritizing of what combustion processes to target for emission mitigations of these health-afflicting and climate-forcing aerosols in the South Asian region. (author)

  18. Source apportionment of size resolved particulate matter at a European air pollution hot spot.

    Science.gov (United States)

    Pokorná, P; Hovorka, J; Klán, M; Hopke, P K

    2015-01-01

    Positive Matrix Factorization-PMF was applied to hourly resolved elemental composition of fine (PM0.15-1.15) and coarse (PM1.15-10) aerosol particles to apportion their sources in the airshed of residential district, Ostrava-Radvanice and Bartovice in winter 2012. Multiple-site measurement by PM2.5 monitors complements the source apportionment. As there were no statistical significant differences amongst the monitors, the source apportionment derived for the central site data is expected to apply to whole residential district. The apportioned sources of the fine aerosol particles were coal combustion (58.6%), sinter production-hot phase (22.9%), traffic (15%), raw iron production (3.5%), and desulfurization slag processing (air pollution sources helped to interpret the PMF solution. PMID:25260163

  19. Source apportionment and the role of meteorological conditions in the assessment of air pollution exposure due to urban emissions

    OpenAIRE

    Schäfer, K.; M. Elsasser; Arteaga-Salas, J. M.; Gu, J; Pitz, M; Schnelle-Kreis, J.; J. Cyrys; Emeis, S.; Prevot, A.S.H.; R. Zimmermann(Physikalisches Institut, University of Bonn, Bonn, Germany)

    2014-01-01

    As particulate matter (PM) impacts human health, knowledge about its composition, exposure and source apportionment is required. A study of the urban atmosphere in the case of Augsburg, Germany, during winter (31 January–12 March 2010) is thus presented here. Investigations were performed on the basis of aerosol mass spectrometry and further air pollutants and meteorological measurements, including mixing layer height. Organic matter was separated by source apportionment ...

  20. Characterization and source apportionment of organic aerosol using offline aerosol mass spectrometry

    OpenAIRE

    Daellenbach, K. R.; Bozzetti, C.; A. Křepelová; F. Canonaco; Wolf, R.; P. Zotter; P. Fermo; Crippa, M.; Slowik, J. G.; Y. Sosedova; Zhang, Yanlin; Huang, R.-J.; L. Poulain; Szidat, Sönke; U. Baltensperger

    2016-01-01

    Field deployments of the Aerodyne Aerosol Mass Spectrometer (AMS) have significantly advanced real-time measurements and source apportionment of non-refractory particulate matter. However, the cost and complex maintenance requirements of the AMS make its deployment at sufficient sites to determine regional characteristics impractical. Furthermore, the negligible transmission efficiency of the AMS inlet for supermicron particles significantly limits the characterization of their chemical natur...

  1. Source apportionment of mercury in dust fallout at urban residential area of Central India

    OpenAIRE

    S. Pervez; G. Balakrishna; Tiwari, S

    2009-01-01

    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 (e.g. industrial complexes composed of a variety of industrial processes, automobiles, construction activities etc.) has put forward the need of source apportionment of these sources indicating their contribution to specific environmental receptor. The study presented...

  2. Chemical mass balance source apportionment for combined PM 2.5 measurements from U.S. non-urban and urban long-term networks

    Science.gov (United States)

    Antony Chen, L.-W.; Watson, John G.; Chow, Judith C.; DuBois, David W.; Herschberger, Lisa

    2010-12-01

    The Minnesota Particulate Matter 2.5 (PM 2.5) Source Apportionment Study was undertaken to explore the utility of PM 2.5 mass, element, ion, and carbon measurements from long-term speciation networks for pollution source attribution. Ambient monitoring data at eight sites across the state were retrieved from the archives of the Interagency Monitoring of Protected Visual Environments (IMPROVE) and the Speciation Trends Network (STN; part of the Chemical Speciation Network [CSN]) and analyzed by an Effective Variance - Chemical Mass Balance (EV-CMB) receptor model with region-specific geological source profiles developed in this study. PM 2.5 was apportioned into contributions of fugitive soil dust, calcium-rich dust, taconite (low grade iron ore) dust, road salt, motor vehicle exhaust, biomass burning, coal-fired utility, and secondary aerosol. Secondary sulfate and nitrate contributed strongly (49-71% of PM 2.5) across all sites and was dominant (≥60%) at IMPROVE sites. Vehicle exhausts accounted for 20-70% of the primary PM 2.5 contribution, largely exceeding the proportion in the primary PM 2.5 emission inventory. The diesel exhaust contribution was separable from the gasoline engine exhaust contribution at the STN sites. Higher detection limits for several marker elements in the STN resulted in non-detectable coal-fired boiler contributions which were detected in the IMPROVE data. Despite the different measured variables, analytical methods, and detection limits, EV-CMB results from a nearby IMPROVE-STN non-urban/urban sites showed similar contributions from regional sources - including fugitive dust and secondary aerosol. Seasonal variations of source contributions were examined and extreme PM 2.5 episodes were explained by both local and regional pollution events.

  3. 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

  4. 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.

  5. 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.

  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. 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.

  9. 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

  10. 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.

  11. 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

  12. Impacts of Oil and Gas Production on Winter Ozone Pollution in the Uintah Basin Using Model Source Apportionment

    Science.gov (United States)

    Tran, H. N. Q.; Tran, T. T.; Mansfield, M. L.; Lyman, S. N.

    2014-12-01

    Contributions of emissions from oil and gas activities to elevated ozone concentrations in the Uintah Basin - Utah were evaluated using the CMAQ Integrated Source Apportionment Method (CMAQ-ISAM) technique, and were compared with the results of traditional budgeting methods. Unlike the traditional budgeting method, which compares simulations with and without emissions of the source(s) in question to quantify its impacts, the CMAQ-ISAM technique assigns tags to emissions of each source and tracks their evolution through physical and chemical processes to quantify the final ozone product yield from the source. Model simulations were performed for two episodes in winter 2013 of low and high ozone to provide better understanding of source contributions under different weather conditions. Due to the highly nonlinear ozone chemistry, results obtained from the two methods differed significantly. The growing oil and gas industry in the Uintah Basin is the largest contributor to the elevated zone (>75 ppb) observed in the Basin. This study therefore provides an insight into the impact of oil and gas industry on the ozone issue, and helps in determining effective control strategies.

  13. Contribution Assessment of Regional Air Pollution over Northeast Asia using CMAQ Source Apportionment Tools

    Science.gov (United States)

    Choi, K.; Woo, J.; Kim, H.; Lee, J.; Kim, C.

    2011-12-01

    East Asia is one of the largest emission source regions in the world because of the large population and fast economic growth for several decades. Recent observation from space also demonstrates that emissions in East Asia - especially China - have been increased impressively since 1995. A number of regional scale transport studies using comprehensive 3D modeling system such as CMAQ have been conducted to understand transboundary air pollution. The contribution assessment using such a comprehensive modeling system, however, was not extensively investigated in this region. Air pollution contributions from multiple source types and regions over East Asia were examined using CMAQ based source apportionment tool off-line coupled with a meteorological model (WRF). The simulation was conducted for the entire year of 2009. The CMAQ ozone & particle precursor tagging methodologies (OPTM) source apportionment tool were applied in our study. An anthropogenic emissions inventory and processing methodology have been developed in support of the source-receptor modeling study in East Asia region. Emissions from open biomass burning and biogenic source were also estimated to support air quality contributions assessment from various sources and source types. Remote sensing-based atmosphere information and ground based monitoring data has been included to evaluate the simulation results. The results of our analysis will be presented at the conference.

  14. 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

  15. 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

  16. Relevance of aerosol size spectrum analysis as support to qualitative source apportionment studies

    International Nuclear Information System (INIS)

    This work presents a diagnostic methodology in support to source apportionment studies to identify remote and local pollution sources. It is based on the temporal analysis of both PM size distributions and PM size fraction correlation along with natural radioactivity measurements as index of Planetary Boundary Layer dynamic. A correlation drop is indicative of changing aerosol sources. When this observation is coupled with decreasing level of natural radioactivity and increasing aerosol concentration, be it coarse or fine, it is indicative of the inflow of remote polluted air masses. The methodology defines in which size range operates the contribution of remote pollution sources. It was applied to two PM10 pollution episodes: the first involved the advection of coarse PM, the second entailed the inflow of two air masses, one transporting coarse dust and the other fine PM. Dust models and backward trajectories analysis confirmed such results, indicating the air mass provenience. - Highlights: ► Tool as a qualitative support to source apportionment studies. ► Time and size resolved aerosol and natural radioactivity measurements. ► Methodology gives immediate information on PM presence from local/remote sources. ► Long range transport episodes are demonstrated without any chemical analysis. ► Dust models and backward-trajectory analysis used for confirming the results found. - Long range transport episodes are clearly demonstrated by time and size resolved aerosol and natural radioactivity measurements without any chemical analysis.

  17. Source apportionment of atmospheric PAHs in the Western Balkans by natural abundance radiocarbon analysis

    Energy Technology Data Exchange (ETDEWEB)

    Zdenek Zencak; Jana Klanova; Ivan Holoubek; Oerjan Gustafsson [Stockholm University, Stockholm (Sweden). Department of Applied Environmental Science

    2007-06-01

    Progress in source apportionment of priority combustion-derived atmospheric pollutants can be made by an inverse approach to inventory emissions, namely, receptor-based compound class-specific radiocarbon analysis (CCSRA) of target pollutants. In the present study, CCSRA of the combustion-derived polycyclic aromatic hydrocarbons (PAHs) present in the atmosphere of the countries of the former republic of Yugoslavia was performed. The carbon stable isotope composition ({delta}{sup 13}C) of PAHs varied between -27.68 and -27.19{per_thousand}, whereas {Delta}{sup 14}C values ranged from -568{per_thousand} for PAHs sampled in Kosovo to -288{per_thousand} for PAHs sampled in the Sarajevo area. The application of an isotopic mass balance model to these {Delta}{sup 14}C data revealed a significant contribution (35-65%) from the combustion of non-fossil material to the atmospheric PAH pollution, even in urban and industrialized areas. Furthermore, consistency was observed between the isotopic composition of PAHs obtained by high-volume sampling and those collected by passive sampling. This encourages the use of passive samplers for CCSRA applications. This marks the first time that a CCSRA investigation could be executed on a geographically wide scale, providing a quantitative field-based source apportionment, which points out that also non-fossil combustion processes should be targeted for remedial action. 36 refs., 1 fig., 3 tabs.

  18. 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.

  19. 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.

  20. 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

  1. 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.

  2. 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

  3. 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

  4. Analytic Methods for Cosmological Likelihoods

    OpenAIRE

    Taylor, A. N.; Kitching, T. D.

    2010-01-01

    We present general, analytic methods for Cosmological likelihood analysis and solve the "many-parameters" problem in Cosmology. Maxima are found by Newton's Method, while marginalization over nuisance parameters, and parameter errors and covariances are estimated by analytic marginalization of an arbitrary likelihood function with flat or Gaussian priors. We show that information about remaining parameters is preserved by marginalization. Marginalizing over all parameters, we find an analytic...

  5. Differences between Magnitudes and Health Impacts of BC Emissions Across the United States using 12 km Scale Seasonal Source Apportionment

    Czech Academy of Sciences Publication Activity Database

    Turner, M.D.; Henze, D.K.; Hakami, A.; Zhao, S.; Resler, Jaroslav; Carmichael, G.; Stanier, C.; Baek, J.; Sandu, A.; Russell, A.G.; Nenes, A.; Jeong, G.; Capps, S.; Percell, P.; Pinder, R.; Napelenok, S.; Bash, J.; Chai, T.

    2015-01-01

    Roč. 49, č. 7 (2015), s. 4362-4371. ISSN 0013-936X Institutional support: RVO:67985807 Keywords : air quality * health impact * source apportionment * adjoint * particulate matter * black carbon Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 5.330, year: 2014

  6. 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...

  7. 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.

  8. 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 NWO grants Nr. 820.01.001, and 834.08.002).

  9. 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

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

    Science.gov (United States)

    Ivey, C. E.; Holmes, H. A.; Hu, Y. T.; Mulholland, J. A.; Russell, A. G.

    2015-07-01

    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 motivating the development of a novel hybrid approach that is used to estimate source impacts by combining the capabilities of receptor models (RMs) and chemical transport models (CTMs). 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 Multiscale Air Quality (CMAQ) model, and the RM approach is based on the chemical mass balance (CMB) 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 for January 2004 over the continental United States. The kriging step is evaluated using data withholding and by comparing results to data from alternative networks. Data withholding also provides an estimate of method uncertainty. Directly applied (hybrid, HYB) and spatially interpolated (spatial hybrid, SH) hybrid adjustment factors at withheld observation sites 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 observation sites using HYB and SH adjustment factors. The mean concentrations of total PM2.5 at withheld observation sites were

  11. Validation of analytical methods

    Directory of Open Access Journals (Sweden)

    Xavier Rius, F.

    2002-03-01

    Full Text Available In this paper we shall discuss the concept of method validation, describe the various elements and explain its close relationship with fitness for purpose. Method validation is based on the assumption that a series of requirements are fulfilled and we shall explain how these requirements are selected, the way in which evidence is supplied and what work has to be carried out in the laboratory. The basic principles of method validation and the different ways to validate a methodology, by inter-laboratory comparison or performing an in-house validation, are also described.En este artículo se discute el concepto de validación del método, se describen los elementos que la componen y se explica la fuerte relación entre la validación y las características de ajuste. El método de validación se basa en el cumplimiento de una serie de requerimientos, se explica como seleccionar esos requerimientos, la forma en que se suministran evidencias, y que trabajo se debe llevar a cabo en el laboratorio. También se describen, los principios básicos del método de validación y los diferentes caminos para validar una metodología, tanto en la comparación entre laboratorios o como cuando se lleva a cabo una validación dentro del laboratorio.

  12. Numerical study of atmospheric particulate matters: source apportionment to characterize 3D transport and transformation of precursors and secondary pollutants

    Science.gov (United States)

    Wu, Dongwei

    In recent years, Mainland China, and in particular the industrial hotbed of the Pearl River Delta (PRD) has experienced an increasingly serious problem of high concentrations of airborne particulate matter. Following the tightening-up of China's air quality policies in recent years, and with especially fine particles now added to a new air quality objective, the identification of major source regions and major types of pollutants has become critically important. In this study, a source-oriented method (Particulate Source Apportionment Technology: PSAT) implemented in 3-D Comprehensive Air Quality Model (CAMx), has been applied to analyze how different emission activities impact fine particle concentration in the PRD region. By using this method, a detailed source region and emission category contribution matrix is derived for all regions within the Hong Kong/PRD region. Source appointment results shows that, in summer and spring time, emissions inside PRD region are the major fine particle sources, contribution 70.7% (11.2 mug/m3) and 52.5% (13.1 mug/m3) to the total figure. Super-regional transports are found to be significant in autumn and winter, contribution 58.5% (20.2 mug/m3) and 64.6% (27.8 mug/m3) of the total fine particles in PRD and Hong Kong region. Another important cause of high PM levels has been the transport of fine particles between cities within the PRD region, with three different regions selected for detailed analysis. Results show that mobile vehicle and industry emission are the two major sources for fine particles. Meanwhile, over the same period in Hong Kong, marine proved to be another very significant source of particle pollutant in addition to the significant impact from motor vehicle. Results show that for the Hong Kong/PRD region local reduction of mobile sources and collaboration between different areas could have succeeded in alleviating the air pollution problem.

  13. Analytical Methods INAA and PIXE Applied to Characterization of Airborne Particulate Matter in Bandung, Indonesia

    Directory of Open Access Journals (Sweden)

    D.D. Lestiani

    2011-08-01

    Full Text Available Urbanization and industrial growth have deteriorated air quality and are major cause to air pollution. Air pollution through fine and ultra-fine particles is a serious threat to human health. The source of air pollution must be known quantitatively by elemental characterization, in order to design the appropriate air quality management. The suitable methods for analysis the airborne particulate matter such as nuclear analytical techniques are hardly needed to solve the air pollution problem. The objectives of this study are to apply the nuclear analytical techniques to airborne particulate samples collected in Bandung, to assess the accuracy and to ensure the reliable of analytical results through the comparison of instrumental neutron activation analysis (INAA and particles induced X-ray emission (PIXE. Particle samples in the PM2.5 and PM2.5-10 ranges have been collected in Bandung twice a week for 24 hours using a Gent stacked filter unit. The result showed that generally there was a systematic difference between INAA and PIXE results, which the values obtained by PIXE were lower than values determined by INAA. INAA is generally more sensitive and reliable than PIXE for Na, Al, Cl, V, Mn, Fe, Br and I, therefore INAA data are preffered, while PIXE usually gives better precision than INAA for Mg, K, Ca, Ti and Zn. Nevertheless, both techniques provide reliable results and complement to each other. INAA is still a prospective method, while PIXE with the special capabilities is a promising tool that could contribute and complement the lack of NAA in determination of lead, sulphur and silicon. The combination of INAA and PIXE can advantageously be used in air pollution studies to extend the number of important elements measured as key elements in source apportionment.

  14. Analytical Methods INAA and PIXE Applied to Characterization of Airborne Particulate Matter in Bandung, Indonesia

    International Nuclear Information System (INIS)

    Urbanization and industrial growth have deteriorated air quality and are major cause to air pollution. Air pollution through fine and ultra-fine particles is a serious threat to human health. The source of air pollution must be known quantitatively by elemental characterization, in order to design the appropriate air quality management. The suitable methods for analysis the airborne particulate matter such as nuclear analytical techniques are hardly needed to solve the air pollution problem. The objectives of this study are to apply the nuclear analytical techniques to airborne particulate samples collected in Bandung, to assess the accuracy and to ensure the reliable of analytical results through the comparison of instrumental neutron activation analysis (INAA) and particles induced X-ray emission (PIXE). Particle samples in the PM2.5 and PM2.5-10 ranges have been collected in Bandung twice a week for 24 hours using a Gent stacked filter unit. The result showed that generally there was a systematic difference between INAA and PIXE results, which the values obtained by PIXE were lower than values determined by INAA. INAA is generally more sensitive and reliable than PIXE for Na, Al, Cl, V, Mn, Fe, Br and I, therefore INAA data are preferred, while PIXE usually gives better precision than INAA for Mg, K, Ca, Ti and Zn. Nevertheless, both techniques provide reliable results and complement to each other. INAA is still a prospective method, while PIXE with the special capabilities is a promising tool that could contribute and complement the lack of NAA in determination of lead, sulphur and silicon. The combination of INAA and PIXE can advantageously be used in air pollution studies to extend the number of important elements measured as key elements in source apportionment. (author)

  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. 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

  17. 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

  18. Source apportionment of arsenic in atmospheric dust fall out in an urban residential area, Raipur, Central India

    OpenAIRE

    G. Balakrishna; S. Pervez; D. S. Bisht

    2011-01-01

    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,...

  19. 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.

  20. Quantitative identification and source apportionment of anthropogenic heavy metals in marine sediment of Hong Kong

    Science.gov (United States)

    Zhou, Feng; Guo, Huaicheng; Liu, Lei

    2007-10-01

    Based on ten heavy metals collected twice annually at 59 sites from 1998 to 2004, enrichment factors (EFs), principal component analysis (PCA) and multivariate linear regression of absolute principal component scores (MLR-APCS) were used in identification and source apportionment of the anthropogenic heavy metals in marine sediment. EFs with Fe as a normalizer and local background as reference values was properly tested and suitable in Hong Kong, and Zn, Ni, Pb, Cu, Cd, Hg and Cr mainly originated from anthropogenic sources, while Al, Mn and Fe were derived from rocks weathering. Rotated PCA and GIS mapping further identified two types of anthropogenic sources and their impacted regions: (1) electronic industrial pollution, riparian runoff and vehicle exhaust impacted the entire Victoria Harbour, inner Tolo Harbour, Eastern Buffer, inner Deep Bay and Cheung Chau; and (2) discharges from textile factories and paint, influenced Tsuen Wan Bay and Kwun Tong typhoon shelter and Rambler Channel. In addition, MLR-APCS was successfully introduced to quantitatively determine the source contributions with uncertainties almost less than 8%: the first anthropogenic sources were responsible for 50.0, 45.1, 86.6, 78.9 and 87.5% of the Zn, Pb, Cu, Cd and Hg, respectively, whereas 49.9% of the Ni and 58.4% of the Cr came from the second anthropogenic sources.

  1. Evaluation of organic markers for chemical mass balance source apportionment at the Fresno Supersite

    Science.gov (United States)

    Chow, J. C.; Watson, J. G.; Lowenthal, D. H.; Chen, L. W. A.; Zielinska, B.; Mazzoleni, L. R.; Magliano, K. L.

    2007-04-01

    Sources of PM2.5 at the Fresno Supersite during high PM2.5 episodes occurring from 15 December 2000-3 February 2001 were estimated with the Chemical Mass Balance (CMB) receptor model. The ability of source profiles with organic markers to distinguish motor vehicle, residential wood combustion (RWC), and cooking emissions was evaluated with simulated data. Organics improved the distinction between gasoline and diesel vehicle emissions and allowed a more precise estimate of the cooking source contribution. Sensitivity tests using average ambient concentrations showed that the gasoline vehicle contribution was not resolved without organics. Organics were not required to estimate hardwood contributions. The most important RWC marker was the water-soluble potassium ion. The estimated cooking contribution did not depend on cholesterol because its concentrations were below the detection limit in most samples. Winter time source contributions were estimated by applying the CMB model to individual and average sample concentrations. RWC was the largest source, contributing 29-31% of measured PM2.5. Hardwood and softwood combustion accounted for 16-17% and 12-15%, respectively. Secondary ammonium nitrate and motor vehicle emissions accounted for 31-33% and 9-15%, respectively. The gasoline vehicle contribution (3-10%) was comparable to the diesel vehicle contribution (5-6%). The cooking contribution was 5-19% of PM2.5. Fresno source apportionment results were consistent with those estimated in previous studies.

  2. Evaluation of organic markers for chemical mass balance source apportionment at the Fresno Supersite

    Directory of Open Access Journals (Sweden)

    J. C. Chow

    2007-01-01

    Full Text Available Sources of PM2.5 at the Fresno Supersite during high PM2.5 episodes occurring from 15 December 2000–3 February 2001 were estimated with the Chemical Mass Balance (CMB receptor model. The ability of source profiles with organic markers to distinguish motor vehicle, residential wood combustion (RWC, and cooking emissions was evaluated with simulated data. Organics improved the distinction between gasoline and diesel vehicle emissions and allowed a more precise estimate of the cooking source contribution. Sensitivity tests using average ambient concentrations showed that the gasoline vehicle contribution was not resolved without organics. Organics were not required to estimate hardwood contributions. The most important RWC marker was the water-soluble potassium ion. The estimated cooking contribution did not depend on cholesterol because its concentrations were below the detection limit in most samples. Winter time source contributions were estimated by applying the CMB model to individual and average sample concentrations. RWC was the largest source, contributing 29–31% of measured PM2.5. Hardwood and softwood combustion accounted for 16–17% and 12–15%, respectively. Secondary ammonium nitrate and motor vehicle emissions accounted for 31–33% and 9–15%, respectively. The gasoline vehicle contribution (3–10% was comparable to the diesel vehicle contribution (5–6%. The cooking contribution was 5–19% of PM2.5. Fresno source apportionment results were consistent with those estimated in previous studies.

  3. The distribution and source apportionment of aliphatic hydrocarbons in soils from the outskirts of Beijing

    Energy Technology Data Exchange (ETDEWEB)

    Youfeng Zhu; Hui Liu; Zhiqun Xi; Xiufeng Liu; Xiaobai Xu [Chinese Academy of Sciences, Research Center for Eco-Environmental Sciences, Beijing (China); Hangxing Cheng [Institute of Geochemical and Geophysical Exploration, Beijing (China)

    2005-03-15

    We report the first extensive study of the spatial distribution and source apportionment of aliphatic hydrocarbons in soils from the Beijing outskirts. Mixed soil samples (5-30 cm depth) were collected for the quantitative determination of n-alkanes, isoprenoids, unresolved complex mixtures and the qualitative determination of hopanes and steranes. The total concentrations, including n-alkanes from C{sub 13} to C{sub 36}, pristane and phytane, were in the range of 0.60-39.92 {mu}g/g, with a median value of 1.97 {mu}g/g. No correlation between soil organic matter content or the percentage of clay and the concentrations was found. Carbon preference index (CPI) values for the whole range of n-alkanes varied between 0.73 and 4.27, with a median value of 1.64, and a contour map of CPI was drawn. A predominance of odd/even carbon n-alkanes and unresolved complex mixtures with different shapes and range were frequently observed. Factor analysis reduced the data set to two principal components explaining 82.82% of the total variation among samples and confirming contributions from low molecular weight species (63.66%) and long-chain n-alkanes (19.27%), respectively. Based on the principal component analysis, the concentration profiles and molecular markers, it was concluded that the aliphatic hydrocarbons were from both biogenic and anthropogenic sources. (Author)

  4. Thia-arenes as source apportionment tracers for urban air particulate

    International Nuclear Information System (INIS)

    Over sixty respirable air particulate samples were selected from a large number of filters collected in Hamilton, Ontario, Canada. Depending on the wind direction these sites were either predominantly upwind or predominantly downwind of the industrial sources. The sixty filters were extracted and analyzed using GC-MS for a range of PAH and sulfur-containing PAH (thia-arenes). Various reference standards (coal tar, diesel exhaust, urban air particulate) and source samples (coke oven condensate) were analyzed as well. A set of air particulate samples collected in another city alongside a highway provided an urban vehicular air sample. Unique thia-arene profiles were noted in the reference and source samples which provided the basis for this source apportionment work; two main approaches were used: (1) analysis of alkylated derivatives of thia-arenes with a molecular mass of 184 amu and (2) analysis of 234 amu isomers. The diesel exhaust and urban vehicular samples gave identical profiles while the coal tar and coke oven samples also had identical profiles but in different respects. The air samples collected at samplers located upwind of the coke ovens showed thia-arene profiles which were similar to the profile observed with a diesel exhaust reference material. However, air samples collected downwind of the coke ovens were heavily loaded samples and resembled the coal tar coke and oven condensate samples

  5. Characterization and source apportionment of particulate matter Sumatra, 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. PMID:17547168

  6. 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.

  7. Quantification of the effects of molecular marker oxidation on source apportionment estimates for motor vehicles

    Science.gov (United States)

    Roy, Anirban A.; Wagstrom, Kristina M.; Adams, Peter J.; Pandis, Spyros N.; Robinson, Allen L.

    2011-06-01

    Molecular markers are individual organic compounds used in receptor models to apportion fine particulate matter to sources. These models currently assume that molecular markers are chemically stable; however, recent laboratory experiments suggest they may be significantly oxidized on atmospherically relevant time scales. To investigate the effects of photo-oxidation, we extended a 3-D chemical transport model (PMCAMx) to simulate norhopane concentrations over the eastern United States during July 2001. Norhopane is an important molecular marker for motor vehicle exhaust. We examined eight different simulation scenarios, using different combinations of reaction rates and source profiles. The simulations including norhopane oxidation better reproduced the observed spatial patterns of norhopane concentrations than the non-reactive cases. Chemical mass balance (CMB) analysis was performed using the PMCAMx-predicted motor vehicle norhopane and elemental carbon (EC) concentrations to quantify the bias caused by oxidation on source apportionment estimates. Norhopane oxidation caused CMB to underestimate total vehicle OC by 10-50%, with larger biases in rural areas. This underestimation was largely due to changes in the amount of OC apportioned to gasoline vehicles which was reduced by as much as 100%. The OC apportioned to diesel vehicle emissions was relatively insensitive to norhopane reaction. Therefore, oxidation can substantially alter CMB estimates regarding the relative importance of gasoline and diesel vehicle emissions.

  8. Source apportionment of aerosol particles near a steel plant by electron microscopy.

    Science.gov (United States)

    Ebert, Martin; Müller-Ebert, Dörthe; Benker, Nathalie; Weinbruch, Stephan

    2012-12-01

    The size, morphology and chemical composition of 37,715 individual particles collected over 22 sampling days in the vicinity of a large integrated steel production were studied by scanning and transmission electron microscopy. Based on the morphology, chemistry and beam stability the particles were classified into the following fourteen groups: silicates, sea salt, calcium sulfates, calcium carbonates, carbonate-silicate mixtures, sulfate-silicate mixtures, iron oxides, iron mixtures, metal oxide-metals, complex secondary particles, soot, Cl-rich particles, P-rich particles, and other particles. The majority of iron oxide (≈85%) and metal oxide-metal (≈70%) particles as well as ≈20% of the silicate particles are fly ashes from high temperature processes. The emissions from the steel work are dominated by iron oxide particles. For source apportionment, seven source categories and two sectors of local wind direction (industrial and urban background) were distinguished. In both sectors PM₁₀ consists of four major source categories: 35% secondary, 20% industrial, 17% soil and 16% soot in the urban background sector compared to 45% industrial, 20% secondary, 13% soil, and 9% soot in the industrial sector. As the secondary and the soot components are higher in the urban background sector than in the industrial sector, it is concluded that both components predominantly originate from urban background sources (traffic, coal burning, and domestic heating). Abatement measures should not only focus on the steel work but should also include the urban background aerosol. PMID:23149950

  9. 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

  10. 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.

  11. Analytical methods under emergency conditions

    International Nuclear Information System (INIS)

    This lecture discusses methods for the radiochemical determination of internal contamination of the body under emergency conditions, here defined as a situation in which results on internal radioactive contamination are needed quickly. The purpose of speed is to determine the necessity for medical treatment to increase the natural elimination rate. Analytical methods discussed include whole-body counting, organ counting, wound monitoring, and excreta analysis. 12 references

  12. Analytic Methods in Nonperturbative QCD

    OpenAIRE

    Simonov, Yu.A.

    2000-01-01

    Recently developed analytic methods in the framework of the Field Correlator Method are reviewed in this series of four lectures and results of calculations are compared to lattice data and experiment. Recent lattice data demonstrating the Casimir scaling of static quark interaction strongly support the FCM and leave very little space for all other theoretical models, e.g. instanton gas/liquid model. Results of calculations for mesons, baryons, quark-gluon plasma and phase transition temperat...

  13. Waste minimization in analytical methods

    International Nuclear Information System (INIS)

    The US Department of Energy (DOE) will require a large number of waste characterizations over a multi-year period to accomplish the Department's goals in environmental restoration and waste management. Estimates vary, but two million analyses annually are expected. The waste generated by the analytical procedures used for characterizations is a significant source of new DOE waste. Success in reducing the volume of secondary waste and the costs of handling this waste would significantly decrease the overall cost of this DOE program. Selection of appropriate analytical methods depends on the intended use of the resultant data. It is not always necessary to use a high-powered analytical method, typically at higher cost, to obtain data needed to make decisions about waste management. Indeed, for samples taken from some heterogeneous systems, the meaning of high accuracy becomes clouded if the data generated are intended to measure a property of this system. Among the factors to be considered in selecting the analytical method are the lower limit of detection, accuracy, turnaround time, cost, reproducibility (precision), interferences, and simplicity. Occasionally, there must be tradeoffs among these factors to achieve the multiple goals of a characterization program. The purpose of the work described here is to add waste minimization to the list of characteristics to be considered. In this paper the authors present results of modifying analytical methods for waste characterization to reduce both the cost of analysis and volume of secondary wastes. Although tradeoffs may be required to minimize waste while still generating data of acceptable quality for the decision-making process, they have data demonstrating that wastes can be reduced in some cases without sacrificing accuracy or precision

  14. Measurement of greenhouse gases (GHGs) and source apportionment in Bakersfield, CA during CALNEX 2010

    Science.gov (United States)

    Guha, A.; Gentner, D. R.; Goldstein, A.; Provencal, R. A.; Gardner, A.; Calnex Bakersfield Science Team

    2010-12-01

    The California Global Warming Solutions Act 2006 creates a need to validate and improve the GHG inventory of the State, which has been largely based on activity and emission factor based estimates. As part of CALNEX 2010, we conducted measurements at the Bakersfield supersite of CO2, CH4, and N2O using fast response laser analyzers (LGR Inc.) to document the ambient mixing ratios of GHGs and analyze their major sources in the region, with an emphasis on understanding emissions of methane (CH4) and nitrous oxide (N2O). The site was located downwind of the urban center during the day and usually experienced a reversal of wind direction at night. Bakersfield is an urban area with heavy industrialization including petroleum refineries, oilfields, manufacturing, and cogeneration plants, all of which can be sources of the abovementioned GHGs. The site was close to a highway and potentially subject to vehicular CH4 and N2O emissions. Hence, CO and a broad variety of VOCs, which can serve as tracers (particularly for vehicle emissions), were included in the measurements to help with source apportionment. In addition to typical urban and industrial sources, Kern County is a rich agricultural region and includes a large number of cattle feedlots, dairies, settling ponds and landfills which are assumed to be some of the largest anthropogenic sources of methane in the State. Additionally, the agricultural industry uses significant amounts of fertilizers, which can lead to production of N2O from the soils along with emissions from controlled biomass burning of agricultural waste. The three GHGs studied show a strong diurnal pattern with concentrations building up in the night-time as the planetary boundary layer (PBL) becomes smaller and reversal in wind direction causes the site to become downwind of some GHG sources like landfills and feedlots. The mean background concentrations at the site (CNO2= 323 ppb; CCO2 = 390 ppm) during the day were consistent with those from the

  15. Characteristics and source apportionment of VOCs measured in an industrial area of Nanjing, Yangtze River Delta, China

    Science.gov (United States)

    An, Junlin; Zhu, Bin; Wang, Honglei; Li, Yongyu; Lin, Xu; Yang, Hui

    2014-11-01

    Based on the data of volatile organic compounds (VOCs) collected continuously in the Nanjing industrial area, the VOCs temporal variability, photochemical reactivity, differences in tracer ratios, and source apportionment by principal component analysis/absolute principal component scores (PCA/APCS) were analyzed. The results showed that the total VOC concentration was 43.5 ppbv, which was 45.1% alkanes, 25.3% alkenes, 7.3% alkynes and 22.3% aromatics. There was an obvious seasonal variation in the of VOCs, with a maximum in summer and minimum in winter, as well as in the VOC components, with alkanes and alkynes highest in winter, alkenes highest in summer, and aromatics highest in spring. The VOCs exhibited significant diurnal variations, i.e. high at night and low during the day. The concentrations of nighttime VOCs were highest to lowest as follows: summer > autumn > spring > winter. By contrast, the concentrations of daytime VOCs were highest to lowest as follows: winter > summer > spring > autumn. The diurnal variation of the VOCs was the largest in autumn and the smallest in winter. The largest diurnal variation of alkanes and alkenes occurred in autumn, whereas the largest diurnal variation of aromatics and alkynes occurred in spring. Using the propylene-equivalent method, alkenes had the highest concentration, followed by aromatics and alkanes. The ratios of T/B, E/B and X/B were 1.2, 1.0 and 0.8, respectively, possibly due to the aging air mass. Based on the specific pollutant ratio method, the observation site was greatly affected by the surrounding industrial areas. The source analysis of the VOCs in the PCA/APCS mode showed that the sources consisted of industrial production sources, automobile emission sources, combustion sources, industrial production volatilization sources, solvent use sources and biogenic emission sources; in addition, there were seasonal variations. Overall, the sources related to industrial production activities accounted for 45

  16. Decision analytic methods in RODOS

    International Nuclear Information System (INIS)

    In the event of a nuclear accident, RODOS seeks to provide decision support at all levels ranging from the largely descriptive to providing a detailed evaluation of the benefits and disadvantages of various countermeasure strategies and ranking them according to the societal preferences as perceived by the decision makers. To achieve this, it must draw upon several decision analytic methods and bring them together in a coherent manner so that the guidance offered to decision makers is consistent from one stage of an accident to the next. The methods used draw upon multi-attribute value and utility theories

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

    Directory of Open Access Journals (Sweden)

    R. J. Sheesley

    2008-12-01

    Full Text Available 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.

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

    Directory of Open Access Journals (Sweden)

    R. J. Sheesley

    2009-05-01

    Full Text Available 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 polycyclic 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 using residential wood combustion (RWC means that 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, which was constrained to 71–87% for the individual PAHs. Indeno[cd]pyrene plus benzo[ghi]perylene had an fbiomass of 71%, while fluoranthene and phenanthrene (gas phase had the highest biomass contribution at 87%. 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 established that RWC is the dominating source of atmospheric PAHs to this region of the boreal zone with some variations among RWC contributions to specific PAHs.

  19. 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.

  20. 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

  1. Source apportionment and water solubility of metals in size segregated particles in urban environments.

    Science.gov (United States)

    Jiang, Sabrina Yanan; Kaul, Daya S; Yang, Fenhuan; Sun, Li; Ning, Zhi

    2015-11-15

    Metals in atmospheric particulate matter (PM) have been associated with various adverse health effects. Different factors contributing to the characterization and distribution of atmospheric metals in urban environments lead to uncertainty of the understanding of their impact on public health. However, few studies have provided a comprehensive picture of the spatial and seasonal variability of metal concentration, solubility and size distribution, all of which have important roles in their contribution to health effects. This study presents an experimental investigation on the characteristics of metals in PM2.5 and coarse PM in two seasons from four urban sites in Hong Kong. The PM samples were extracted separately with aqua regia and water, and a total of sixteen elements were analyzed using ICP-MS and ICP-OES to determine the size segregated concentration and solubility of metals. The concentrations of major metals were distributed in similar patterns with the same order of magnitude among different urban sites. Source apportionment using Positive Matrix Factorization (PMF) indicated that three sources namely road dust, vehicular exhaust and ship emission are major contributors to the urban atmospheric metal concentrations in Hong Kong with distinctly different profiles between coarse PM and PM2.5 fractions. The individual metals were assigned to different sources, consistent with literature documentation, except potassium emerging with substantial contribution from vehicle exhaust emission. Literature data from past studies on both local and other cities were compared to the results from the present study to investigate the impact of different emission sources and control policies on metal distribution in urban atmosphere. A large variation of solubility among the metals reflected that the majority of metals in PM2.5 were more soluble than those in coarse PM indicating size dependent chemical states of metals. The data from this study provides a rich dataset of

  2. 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.

  3. Aerosol source apportionment from 1 year measurements at the CESAR tower at Cabauw, NL

    Science.gov (United States)

    Schlag, P.; Kiendler-Scharr, A.; Blom, M. J.; Canonaco, F.; Henzing, J. S.; Moerman, M. M.; Prévôt, A. S. H.; Holzinger, R.

    2015-12-01

    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, NL. The campaign lasted nearly one year from July 2012 to June 2013 as part of the ACTRIS project. Including black carbon data 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 %). 12 exceedances of the World Health Organization (WHO) PM2.5 daily mean limit (25 μg m-3) were 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 (SOA, 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 ageing 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.

  4. 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.

  5. 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

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

    DEFF Research Database (Denmark)

    Nguyen, Q. T.; Skov, Henrik; Sørensen, L. L.;

    2013-01-01

    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...... 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....

  7. 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

  8. 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

  9. 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

  10. 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.

  11. 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).

  12. 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

  13. 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

  14. The 2013 severe haze over southern Hebei, China: model evaluation, source apportionment, and policy implications

    Science.gov (United States)

    Wang, L. T.; Wei, Z.; Yang, J.; Zhang, Y.; Zhang, F. F.; Su, J.; Meng, C. C.; Zhang, Q.

    2014-03-01

    Extremely severe and persistent haze occurred in January 2013 over eastern and northern China. The record-breaking high concentrations of fine particulate matter (PM2.5) of more than 700 μg m-3 on hourly average and the persistence of the episodes have raised widespread, considerable public concerns. During that period, 7 of the top 10 polluted cities in China were within the Hebei Province. The three cities in southern Hebei (Shijiazhuang, Xingtai, and Handan) have been listed as the top three polluted cities according to the statistics for the first half of the year 2013. In this study, the Mesoscale Modeling System Generation 5 (MM5) and the Models-3/Community Multiscale Air Quality (CMAQ) modeling system are applied to simulate the 2013 severe winter regional hazes in East Asia and northern China at horizontal grid resolutions of 36 and 12 km, respectively, using the Multi-resolution Emission Inventory for China (MEIC). The source contributions of major source regions and sectors to PM2.5 concentrations in the three most polluted cities in southern Hebei are quantified by aiming at the understanding of the sources of the severe haze pollution in this region, and the results are compared with December 2007, the haziest month in the period 2001-2010. Model evaluation against meteorological and air quality observations indicates an overall acceptable performance and the model tends to underpredict PM2.5 and coarse particulate matter (PM10) concentrations during the extremely polluted episodes. The MEIC inventory is proven to be a good estimation in terms of total emissions of cities but uncertainties exist in the spatial allocations of emissions into fine grid resolutions within cities. The source apportionment shows that emissions from northern Hebei and the Beijing-Tianjin city cluster are two major regional contributors to the pollution in January 2013 in Shijiazhuang, compared with those from Shanxi and northern Hebei for December 2007. For Xingtai and Handan

  15. The 2013 severe haze over the southern Hebei, China: model evaluation, source apportionment, and policy implications

    Science.gov (United States)

    Wang, L. T.; Wei, Z.; Yang, J.; Zhang, Y.; Zhang, F. F.; Su, J.; Meng, C. C.; Zhang, Q.

    2013-11-01

    Extremely severe and persistent haze occurred in January 2013 over the eastern and northern China. The record-breaking high concentrations of fine particulate matter (PM2.5) of more than 700 μg m-3 on hourly average and the persistence of the episodes have raised widespread, considerable public concerns. During that period, seven of the top ten polluted cities in China were within Hebei Province. The three cities in southern Hebei, Shijiazhuang, Xingtai, and Handan, have been listed as the top three polluted cities according to the statistics for the first half year of 2013. In this study, the Mesoscale Modeling System Generation 5 (MM5) and the Models-3/Community Multiscale Air Quality (CMAQ) modeling system are applied to simulate the 2013 severe winter regional hazes in East Asia and the northern China at horizontal grid resolutions of 36 and 12 km, respectively, using the Multi-resolution Emission Inventory of China (MEIC). The source contributions of major source regions and sectors to PM2.5 concentrations in the three most-polluted cities in southern Hebei are quantified aiming at the understanding of the sources of the severe haze pollution in this region, and the results are compared with December 2007, the haziest month in 2001-2010. Model evaluation against meteorological and air quality observations indicates an overall acceptable performance and the model tends to underpredict PM2.5 and coarse particulate matter (PM10) concentrations during the extremely severe polluted episodes. The MEIC inventory is proved to be a good estimation in terms of total emissions of cities but uncertainties exist in the spatial allocations of emissions into fine grid resolutions within cities. The source apportionment shows that emissions from the northern Hebei and the Beijing-Tianjin city cluster are two major regional contributors to the pollution in January 2013 in Shijiazhuang, comparing with those from Shanxi and the northern Hebei for December 2007. For Xingtai and

  16. 7 CFR 94.303 - Analytical methods.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Analytical methods. 94.303 Section 94.303 Agriculture... POULTRY AND EGG PRODUCTS Processed Poultry Products § 94.303 Analytical methods. The analytical methods... latest edition of the Official Methods of Analysis of AOAC INTERNATIONAL, Suite 500, 481 North...

  17. 7 CFR 98.4 - Analytical methods.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Analytical methods. 98.4 Section 98.4 Agriculture....4 Analytical methods. (a) The majority of analytical methods used by the USDA laboratories to perform analyses of meat, meat food products and MRE's are listed as follows: (1) Official Methods...

  18. 7 CFR 93.4 - Analytical methods.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Analytical methods. 93.4 Section 93.4 Agriculture... PROCESSED FRUITS AND VEGETABLES Citrus Juices and Certain Citrus Products § 93.4 Analytical methods. (a) The majority of analytical methods for citrus products are found in the Official Methods of Analysis of...

  19. Integrating Source Apportionment Tracers into a Bottom-up Inventory of Methane Emissions in the Barnett Shale Hydraulic Fracturing Region.

    Science.gov (United States)

    Townsend-Small, Amy; Marrero, Josette E; Lyon, David R; Simpson, Isobel J; Meinardi, Simone; Blake, Donald R

    2015-07-01

    A growing dependence on natural gas for energy may exacerbate emissions of the greenhouse gas methane (CH4). Identifying fingerprints of these emissions is critical to our understanding of potential impacts. Here, we compare stable isotopic and alkane ratio tracers of natural gas, agricultural, and urban CH4 sources in the Barnett Shale hydraulic fracturing region near Fort Worth, Texas. Thermogenic and biogenic sources were compositionally distinct, and emissions from oil wells were enriched in alkanes and isotopically depleted relative to natural gas wells. Emissions from natural gas production varied in δ(13)C and alkane ratio composition, with δD-CH4 representing the most consistent tracer of natural gas sources. We integrated our data into a bottom-up inventory of CH4 for the region, resulting in an inventory of ethane (C2H6) sources for comparison to top-down estimates of CH4 and C2H6 emissions. Methane emissions in the Barnett are a complex mixture of urban, agricultural, and fossil fuel sources, which makes source apportionment challenging. For example, spatial heterogeneity in gas composition and high C2H6/CH4 ratios in emissions from conventional oil production add uncertainty to top-down models of source apportionment. Future top-down studies may benefit from the addition of δD-CH4 to distinguish thermogenic and biogenic sources. PMID:26148556

  20. 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.

  1. 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

  2. On the autarchic use of solely PIXE data in particulate matter source apportionment studies by receptor modeling

    Science.gov (United States)

    Lucarelli, F.; Nava, S.; Calzolai, G.; Chiari, M.; Giannoni, M.; Traversi, R.; Udisti, R.

    2015-11-01

    Particle Induced X-ray Emission (PIXE) analysis of aerosol samples allows simultaneous detection of several elements, including important tracers of many particulate matter sources. This capability, together with the possibility of analyzing a high number of samples in very short times, makes PIXE a very effective tool for source apportionment studies by receptor modeling. However, important aerosol components, like nitrates, OC and EC, cannot be assessed by PIXE: this limitation may strongly compromise the results of a source apportionment study if based on PIXE data alone. In this work, an experimental dataset characterised by an extended chemical speciation (elements, EC-OC, ions) is used to test the effect of reducing input species in the application of one of the most widely used receptor model, namely Positive Matrix Factorization (PMF). The main effect of using only PIXE data is that the secondary nitrate source is not identified and the contribution of biomass burning is overestimated, probably due to the similar seasonal pattern of these two sources.

  3. 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)

  4. 7 CFR 94.4 - Analytical methods.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Analytical methods. 94.4 Section 94.4 Agriculture... POULTRY AND EGG PRODUCTS Mandatory Analyses of Egg Products § 94.4 Analytical methods. The majority of analytical methods used by the USDA laboratories to perform mandatory analyses for egg products are listed...

  5. 7 CFR 94.103 - Analytical methods.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Analytical methods. 94.103 Section 94.103 Agriculture... POULTRY AND EGG PRODUCTS Voluntary Analyses of Egg Products § 94.103 Analytical methods. The analytical methods used by the Science and Technology Division laboratories to perform voluntary analyses for...

  6. Source apportionment of air pollution in China: Extending the usefulness of receptor modeling by combining multivariate and chemical mass balance models

    International Nuclear Information System (INIS)

    The research explores the possibility of using a two step method of identifying and quantifying air pollution emissions in an urban environment. The procedures uses a mathematical model called Target Transformation Factor Analysis (TTFA) to estimate source profiles using ambient trace element air concentration data. A source profile is analogous to a fingerprint since it is unique to each source of air pollution. The profiles estimated by TTFA are then employed in a Chemical Mass Balance (CMB) source apportionment analysis for the air shed. Other known sources are estimated using source signatures from the literature. Applying the TTFA and CMB models in this fashion is called receptor modeling. Generically, a receptor model is the combination of measured air pollution concentration data with a numerical technique which apportions the measured air pollution among distinct source types. The results show that TTFA can be used to provide quantitative estimates of air pollution source profiles for an urban center in China. The number of profiles for unique source types was limited for the data set since emissions from certain types of sources co-varied during each sampling day. Consequently, the CMB analyses that applied the TTFA source profiles needed to be supplemented with standard U.S. EPA source profiles

  7. Analytical methods used at model facility

    International Nuclear Information System (INIS)

    A description of analytical methods used at the model LEU Fuel Fabrication Facility is presented. The methods include gravimetric uranium analysis, isotopic analysis, fluorimetric analysis, and emission spectroscopy

  8. 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.

  9. 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

  10. AIRUSE-LIFE+: a harmonized PM speciation and source apportionment in 5 Southern European cities

    Science.gov (United States)

    Amato, F.; Alastuey, A.; Karanasiou, A.; Lucarelli, F.; Nava, S.; Calzolai, G.; Severi, M.; Becagli, S.; Gianelle, V. L.; Colombi, C.; Alves, C.; Custódio, D.; Nunes, T.; Cerqueira, M.; Pio, C.; Eleftheriadis, K.; Diapouli, E.; Reche, C.; Minguillón, M. C.; Manousakas, M.; Maggos, T.; Vratolis, S.; Harrison, R. M.; Querol, X.

    2015-09-01

    The AIRUSE-LIFE+ project aims at characterising similarities and heterogeneities in PM sources and contributions in urban areas from the 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, MLN-UB) one sub-urban background site (Athens, ATH-SUB) and one traffic site (Porto, POR-TR). After collecting 1047 PM10 and 1116 PM2.5 24 h samples from January 2013 to February 2014 simultaneously at the 5 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 datasets in a harmonised way for each city. The sum of vehicle exhaust and non-exhaust contributes within 3.9-10.8 μg m-3 (16-32 %) to PM10 and 2.3-9.4 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, sulphate 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 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 used as fuel in 96 % of homes, while, in other cities, PM levels increase on an annual basis by 1-9 μg m-3 due to this

  11. Analytical mechanics methods for solving Whittaker equations

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The purpose of this paper is to study the solution of the celebrated Whittaker equations by using analytical mechanics methods, including the Lagrange-Noether method, Hamilton-Poisson method and potential integral method.

  12. 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.

  13. A new methodology to assess the performance and uncertainty of source apportionment models II: The results of two European intercomparison exercises

    Science.gov (United States)

    Belis, C. A.; Karagulian, F.; Amato, F.; Almeida, M.; Artaxo, P.; Beddows, D. C. S.; Bernardoni, V.; Bove, M. C.; Carbone, S.; Cesari, D.; Contini, D.; Cuccia, E.; Diapouli, E.; Eleftheriadis, K.; Favez, O.; El Haddad, I.; Harrison, R. M.; Hellebust, S.; Hovorka, J.; Jang, E.; Jorquera, H.; Kammermeier, T.; Karl, M.; Lucarelli, F.; Mooibroek, D.; Nava, S.; Nøjgaard, J. K.; Paatero, P.; Pandolfi, M.; Perrone, M. G.; Petit, J. E.; Pietrodangelo, A.; Pokorná, P.; Prati, P.; Prevot, A. S. H.; Quass, U.; Querol, X.; Saraga, D.; Sciare, J.; Sfetsos, A.; Valli, G.; Vecchi, R.; Vestenius, M.; Yubero, E.; Hopke, P. K.

    2015-12-01

    The performance and the uncertainty of receptor models (RMs) were assessed in intercomparison exercises employing real-world and synthetic input datasets. To that end, the results obtained by different practitioners using ten different RMs were compared with a reference. In order to explain the differences in the performances and uncertainties of the different approaches, the apportioned mass, the number of sources, the chemical profiles, the contribution-to-species and the time trends of the sources were all evaluated using the methodology described in Belis et al. (2015). In this study, 87% of the 344 source contribution estimates (SCEs) reported by participants in 47 different source apportionment model results met the 50% standard uncertainty quality objective established for the performance test. In addition, 68% of the SCE uncertainties reported in the results were coherent with the analytical uncertainties in the input data. The most used models, EPA-PMF v.3, PMF2 and EPA-CMB 8.2, presented quite satisfactory performances in the estimation of SCEs while unconstrained models, that do not account for the uncertainty in the input data (e.g. APCS and FA-MLRA), showed below average performance. Sources with well-defined chemical profiles and seasonal time trends, that make appreciable contributions (>10%), were those better quantified by the models while those with contributions to the PM mass close to 1% represented a challenge. The results of the assessment indicate that RMs are capable of estimating the contribution of the major pollution source categories over a given time window with a level of accuracy that is in line with the needs of air quality management.

  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

    Science.gov (United States)

    Manousakas, M.; Diapouli, E.; Papaefthymiou, H.; Migliori, A.; Karydas, A. G.; Padilla-Alvarez, R.; Bogovac, M.; Kaiser, R. B.; Jaksic, M.; Bogdanovic-Radovic, I.; Eleftheriadis, K.

    2015-04-01

    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 PM10 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/m3), biomass burning 19% (4.43 ± 0.27 μg/m3), road dust 15% (3.63 ± 0.37 μg/m3), power plant emissions 13% (3.01 ± 0.44 μg/m3), traffic 12% (2.82 ± 0.37 μg/m3), and sea spray 8% (1.99 ± 0.41 μg/m3). 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. Reactor Section standard analytical methods. Part 1

    Energy Technology Data Exchange (ETDEWEB)

    Sowden, D.

    1954-07-01

    the Standard Analytical Methods manual was prepared for the purpose of consolidating and standardizing all current analytical methods and procedures used in the Reactor Section for routine chemical analyses. All procedures are established in accordance with accepted practice and the general analytical methods specified by the Engineering Department. These procedures are specifically adapted to the requirements of the water treatment process and related operations. The methods included in this manual are organized alphabetically within the following five sections which correspond to the various phases of the analytical control program in which these analyses are to be used: water analyses, essential material analyses, cotton plug analyses boiler water analyses, and miscellaneous control analyses.

  16. Source apportionment of particulate matter (PM 2.5) in an urban area using dispersion, receptor and inverse modelling

    Science.gov (United States)

    Laupsa, Herdis; Denby, Bruce; Larssen, Steinar; Schaug, Jan

    Air pollution emission inventories are the basis for air quality assessment and management strategies. The quality of the inventories is of great importance since these data are essential for air pollution impact assessments using dispersion models. In this study, the quality of the emission inventory for fine particulates (PM 2.5) is assessed: first, using the calculated source contributions from a receptor model; second, using source apportionment from a dispersion model; and third, by applying a simple inverse modelling technique which utilises multiple linear regression of the dispersion model source contributions together with the observed PM 2.5 concentrations. For the receptor modelling the chemical composition of PM 2.5 filter samples from a measurement campaign performed between January 2004 and April 2005 are analysed. Positive matrix factorisation is applied as the receptor model to detect and quantify the various source contributions. For the same observational period and site, dispersion model calculations using the Air Quality Management system, AirQUIS, are performed. The results identify significant differences between the dispersion and receptor model source apportionment, particularly for wood burning and traffic induced suspension. For wood burning the receptor model calculations are lower, by a factor of 0.54, but for the traffic induced suspension they are higher, by a factor of 7.1. Inverse modelling, based on regression of the dispersion model source contributions and the PM 2.5 concentrations, indicates similar discrepancies in the emissions inventory. In order to assess if the differences found at the one site are generally applicable throughout Oslo, the individual source category emissions are rescaled according to the receptor modelling results. These adjusted PM 2.5 concentrations are compared with measurements at four independent stations to evaluate the updated inventory. Statistical analysis shows improvement in the estimated

  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. Concentrations and source apportionment of PM10 and associated major and trace elements in the Rhodes Island, Greece.

    Science.gov (United States)

    Argyropoulos, Georgios; Manoli, Evangelia; Kouras, Athanasios; Samara, Constantini

    2012-08-15

    Ambient concentrations of PM(10) and associated major and trace elements were measured over the cold and the warm season of 2007 at two sites located in the Rhodes Island (Greece), in Eastern Mediterranean, aimed at source apportionment by Chemical Mass Balance (CMB) receptor modeling. Source chemical profiles, necessary in CMB modeling, were obtained for a variety of emission sources that could possibly affect the study area, including sea spray, geological material, soot emissions from the nearby oil-fuelled thermal power plant, and other anthropogenic activities, such as vehicular traffic, residential oil combustion, wood burning, and uncontrolled open-air burning of agricultural biomass and municipal waste. Source apportionment of PM(10) and elemental components was carried out by employing an advanced CMB version, the Robotic Chemical Mass Balance model (RCMB). Vehicular emissions were found to be major PM(10) contributor accounting, on average, for 36.8% and 31.7% during the cold period, and for 40.9% and 39.2% in the warm period at the two sites, respectively. The second largest source of ambient PM(10), with minor seasonal variation, was secondary sulfates (mainly ammonium and calcium sulfates), with total average contribution around 16.5% and 18% at the two sites. Soil dust was also a remarkable source contributing around 22% in the warm period, whereas only around 10% in the cold season. Soot emitted from the thermal power plant was found to be negligible contributor to ambient PM(10) (burning aerosol from the countries surrounding the Black Sea was considered possible. PMID:22705902

  19. New insight into the spatiotemporal variability and source apportionments of C1-C4 alkyl nitrates in Hong Kong

    Science.gov (United States)

    Ling, Z. H.; Guo, H.; Simpson, I. J.; Saunders, S. M.; Lam, S. H. M.; Lyu, X. P.; Blake, D. R.

    2015-08-01

    Alkyl nitrates (RONO2) were measured concurrently at a mountain site (TMS) and an urban site (TW) at the foot of the same mountain in Hong Kong from September to November 2010, when high O3 mixing ratios were frequently observed. The abundance and temporal patterns of five C1-C4 RONO2 and their parent hydrocarbons (RH), the RONO2/RH ratios and photochemical age of air masses at TMS differed from those at TW, reflecting different contributions of direct emissions and secondary formation of RONO2 at the two sites. Relative to 2-BuONO2/n-butane, the measured ratios of C1-C2 RONO2/RH at the two sites exhibited significant positive deviations from pure photochemical (PP) curves and background initial ratio (BIR) curves obtained from laboratory kinetic data, suggesting that background mixing ratios had a significant influence on the RONO2 and RH distributions. In contrast to the C1-C2 RONO2/RH ratios, the evolution for the measured ratios of C3 RONO2/RH to 2-BuONO2/n-butane agreed well with the ratio distributions in the PP and BIR curves at the two sites. Furthermore, the ratios of 1-/2-PrONO2 and yields of 1- and 2-PrONO2 suggested that the C3 RONO2 were mainly from secondary formation at TMS, whereas secondary formation and other additional sources had a significant influence on C3 RONO2 mixing ratios at TW. The source apportionment results confirmed that secondary formation was the dominant contributor to all the RONO2 at TMS, while most of the RONO2 at TW were from secondary formation and biomass burning. The findings of the source apportionments and photochemical evolution of RONO2 are helpful to evaluate photochemical processing in Hong Kong using RONO2 as an indicator.

  20. 7 CFR 91.23 - Analytical methods.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Analytical methods. 91.23 Section 91.23 Agriculture... SERVICES AND GENERAL INFORMATION Method Manuals § 91.23 Analytical methods. Most analyses are performed according to approved procedures described in manuals of standardized methodology. These standard...

  1. 40 CFR 141.89 - Analytical methods.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Analytical methods. 141.89 Section 141...) NATIONAL PRIMARY DRINKING WATER REGULATIONS Control of Lead and Copper § 141.89 Analytical methods. (a... shall be conducted with the methods in § 141.23(k)(1). (1) Analyses for alkalinity,...

  2. 7 CFR 93.13 - Analytical methods.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Analytical methods. 93.13 Section 93.13 Agriculture... PROCESSED FRUITS AND VEGETABLES Peanuts, Tree Nuts, Corn and Other Oilseeds § 93.13 Analytical methods... manuals: (a) Approved Methods of the American Association of Cereal Chemists (AACC), American...

  3. 40 CFR 141.704 - Analytical methods.

    Science.gov (United States)

    2010-07-01

    ... Federal Register approves this incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Analytical methods. 141.704 Section... Monitoring Requirements § 141.704 Analytical methods. (a) Cryptosporidium. Systems must analyze...

  4. HTGR analytical methods and design verification

    International Nuclear Information System (INIS)

    Analytical methods for the high-temperature gas-cooled reactor (HTGR) include development, update, verification, documentation, and maintenance of all computer codes for HTGR design and analysis. This paper presents selected nuclear, structural mechanics, seismic, and systems analytical methods related to the HTGR core. This paper also reviews design verification tests in the reactor core, reactor internals, steam generator, and thermal barrier

  5. Analytical detection methods for irradiated foodstuff

    International Nuclear Information System (INIS)

    Some analytical detection methods are used in the world. A detail of establishment of CEN Standards in 1996, one of them, is explained. Nine standards of CEN are adopted by the Codex Standards (General Codex Methods for detection of irradiated Food). Main analytical technologies and the standard method are stated. As the physical methods, ESR (Electron Spin Resonance), TL and PSL (Photostimulated Luminescence) method are described. On chemical methods, hydrocarbons method, 2-alkylcyclobutanone method and other methods are discussed. DNA method, DEFT/APC, LAL/GNB and DEFT/APC method are explained as the biological methods. The application methods of irradiated food and classification of analytical detection methods are shown. References after 1996 are reviewed. (S.Y.)

  6. 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.

  7. 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

  8. Characterization of emissions from South Asian biofuels and application to source apportionment of carbonaceous aerosol in the Himalayas

    Science.gov (United States)

    Stone, Elizabeth A.; Schauer, James J.; Pradhan, Bidya Banmali; Dangol, Pradeep Man; Habib, Gazala; Venkataraman, Chandra; Ramanathan, V.

    2010-03-01

    This study focuses on improving source apportionment of carbonaceous aerosol in South Asia and consists of three parts: (1) development of novel molecular marker-based profiles for real-world biofuel combustion, (2) application of these profiles to a year-long data set, and (3) evaluation of profiles by an in-depth sensitivity analysis. Emissions profiles for biomass fuels were developed through source testing of a residential stove commonly used in South Asia. Wood fuels were combusted at high and low rates, which corresponded to source profiles high in organic carbon (OC) or high in elemental carbon (EC), respectively. Crop wastes common to the region, including rice straw, mustard stalk, jute stalk, soybean stalk, and animal residue burnings, were also characterized. Biofuel profiles were used in a source apportionment study of OC and EC in Godavari, Nepal. This site is located in the foothills of the Himalayas and was selected for its well-mixed and regionally impacted air masses. At Godavari, daily samples of fine particulate matter (PM2.5) were collected throughout the year of 2006, and the annual trends in particulate mass, OC, and EC followed the occurrence of a regional haze in South Asia. Maximum concentrations occurred during the dry winter season and minimum concentrations occurred during the summer monsoon season. Specific organic compounds unique to aerosol sources, molecular markers, were measured in monthly composite samples. These markers implicated motor vehicles, coal combustion, biomass burning, cow dung burning, vegetative detritus, and secondary organic aerosol as sources of carbonaceous aerosol. A molecular marker-based chemical mass balance (CMB) model provided a quantitative assessment of primary source contributions to carbonaceous aerosol. The new profiles were compared to widely used biomass burning profiles from the literature in a sensitivity analysis. This analysis indicated a high degree of stability in estimates of source

  9. Nuclear microprobe analysis and source apportionment of individual atmospheric aerosol particles

    International Nuclear Information System (INIS)

    In atmospheric aerosol reserach, one key issue is to determine the sources of the airborne particles. Bulk PIXE analysis coupled with receptor modeling provides a useful, but limited view of the aerosol sources influencing one particular site or sample. The scanning nuclear microprobe (SNM) technique is a microanalytical technique that gives unique information on individual aerosol particles. In the SNM analyses a 1.0 μm size 2.4 MeV proton beam from the Oxford SNM was used. The trace elements with Z>11 were measured by the particle induced X-ray emission (PIXE) method with detection limits in the 1-10 ppm range. Carbon, nitrogen and oxygen are measured simultaneously using Rutherford backscattering spectrometry (RBS). Atmospheric aerosol particles were collected at the Brazilian Antarctic Station and at biomass burning sites in the Amazon basin tropical rain forest in Brazil. In the Antarctic samples, the sea-salt aerosol particles were clearly predominating, with NaCl and CaSO4 as major compounds with several trace elements as Al, Si, P, K, Mn, Fe, Ni, Cu, Zn, Br, Sr, and Pb. Factor analysis of the elemental data showed the presence of four components: 1) Soil dust particles; 2) NaCl particles; 3) CaSO4 with Sr; and 4) Br and Mg. Strontium, observed at 20-100 ppm levels, was always present in the CaSO4 particles. The hierarchical cluster procedure gave results similar to the ones obtained through factor analysis. For the tropical rain forest biomass burning aerosol emissions, biogenic particles with a high organic content dominate the particle population, while K, P, Ca, Mg, Zn, and Si are the dominant elements. Zinc at 10-200 ppm is present in biogenic particles rich in P and K. The quantitative aspects and excellent detection limits make SNM analysis of individual aerosol particles a very powerful analytical tool. (orig.)

  10. Analytical Methods in Mesoscopic Systems

    Science.gov (United States)

    Mason, Douglas Joseph

    The prospect of designing technologies around the quantum behavior of mesoscopic devices is enticing. This thesis present several tools to facilitate the process of calculating and analyzing the quantum properties of such devices - resonance, boundary conditions, and the quantum-classical correspondence are major themes that we study with these tools. In Chapter 1, we begin by laying the groundwork for the tools that follow by defining the Hamiltonian, the Green's function, the scattering matrix, and the Landauer formalism for ballistic conduction. In Chapter 2, we present an efficient and easy-to-implement algorithm called the Outward Wave Algorithm, which calculates the conductance function and scattering density matrix when a system is coupled to an environment in a variety of geometries and contexts beyond the simple two-lead schematic. In Chapter 3, we present a unique geometry and numerical method called the Boundary Reflectin Matrix that allows us to calculate the full scattering matrix from arbitrary boundaries of a lattice system, and introduce the phenomenon of internal Bragg diffraction. In Chapter 4, we present a new method for visualizing wavefunctions called the Husimi map, which uses measurement by coherent states to form a bridge between the quantum flux operator and semiclassics. We extend the formalism from Chapter 4 to lattice systems in Chapter 5, and comment on our results in Chapter 3 and other work in the literature. These three tools - the Outward Wave Algorithm, the Boundary Reflection Matrix, and the Husimi map - work together to throw light on our interpretation of resonance and scattering in quantum systems, effectively codifying the expertise developed in semiclassics over the past few decades in an efficient and robust package. The data and images that they make available promise to help design better technologies based on quantum scattering.

  11. 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.

  12. 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

  13. 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 industrial emissions on PAH concentrations. Monte Carlo source apportionment using diagnostic ratios showed that 80 ± 10% of the average LMW PAH concentrations were contributed by petroleum vapor emissions, while 53 ± 19% of high molecular weight (HMW) PAH were from solid fuel combustion emissions. The positive matrix factorization model estimated that 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.

  14. Mathematical methods for physical and analytical chemistry

    CERN Document Server

    Goodson, David Z

    2011-01-01

    Mathematical Methods for Physical and Analytical Chemistry presents mathematical and statistical methods to students of chemistry at the intermediate, post-calculus level. The content includes a review of general calculus; a review of numerical techniques often omitted from calculus courses, such as cubic splines and Newton's method; a detailed treatment of statistical methods for experimental data analysis; complex numbers; extrapolation; linear algebra; and differential equations. With numerous example problems and helpful anecdotes, this text gives chemistry students the mathematical

  15. 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

  16. 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.

  17. 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

  18. Environmental carcinogenic polycyclic aromatic hydrocarbons in soil from Himalayas, India: Implications for spatial distribution, sources apportionment and risk assessment.

    Science.gov (United States)

    Devi, Ningombam Linthoingambi; Yadav, Ishwar Chandra; Shihua, Qi; Dan, Yang; Zhang, Gan; Raha, Priyankar

    2016-02-01

    The Indian Himalayan Region (IHR) is one of the important mountain ecosystems among the global mountain system which support wide variety of flora, fauna, human communities and cultural diversities. Surface soil samples (n = 69) collected from IHR were analysed for 16 priority polycyclic aromatic hydrocarbons (PAH) listed by USEPA. The ∑16PAH concentration in surface soil ranged from 15.3 to 4762 ngg(-1) (mean 458 ngg(-1)). The sum total of low molecular weight PAH (∑LMW-PAHs) (mean 74.0 ngg(-1)) were relatively lower than the high molecular weight PAH (∑HMW-PAHs) (mean 384 ngg(-1)). The concentration of eight carcinogenic PAHs (BaA, CHR, BbF, BkF, BaP, DahA, IcdP, BghiP) were detected high in mountain soil from IHR and ranged from 0.73 to 2729 ngg(-1) (mean 272 ngg(-1)). Based on spatial distribution map, high concentration of HMW- and LMW-PAHs were detected at GS1 site in Guwahati (615 and 4071 ngg(-1)), and lowest concentration of HMW-PAHs were found at IS6 in Itanagar (5.80 ngg(-1)) and LMW-PAHs at DS2 (17.3 ngg(-1)) in Dibrugarh. Total organic carbon (TOC) in mountain soil was poorly connected with ∑PAHs (r(2) = 0.072) and Car-PAHs (r(2) = 0.048), suggesting the little role of TOC in adsorption of PAHs. Isomeric ratio of PAHs showed the source of PAH contamination in IHR is mixed of petrogenic and pyrogenic origin and was affirmed by PAHs composition profile. These source apportionment results were further confirmed by principal component analysis (PCA). Eco-toxicological analysis showed the calculated TEQ for most carcinogenic PAH were 2-4 times more than the Dutch allowed limit, while TEQ of BaP was 25 times high, suggesting increasing trend of carcinogenicity of surface soil. PMID:26386774

  19. 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.

  20. 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)

  1. 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.

  2. Analytic compensation methods in dynamic tomography

    International Nuclear Information System (INIS)

    Recent progresses in X-ray tomography allow to study some organs dynamically. The aim of this work is to analyze the deformation compensation algorithms used to integrate dynamical evolution models into the image reconstruction processes. An exact and efficient analytical method of movement compensation is presented and applied to simulated data. Abstract only. (J.S.)

  3. Numerical and analytical methods with Matlab

    CERN Document Server

    Bober, William; Masory, Oren

    2013-01-01

    Numerical and Analytical Methods with MATLAB® presents extensive coverage of the MATLAB programming language for engineers. It demonstrates how the built-in functions of MATLAB can be used to solve systems of linear equations, ODEs, roots of transcendental equations, statistical problems, optimization problems, control systems problems, and stress analysis problems. These built-in functions are essentially black boxes to students. By combining MATLAB with basic numerical and analytical techniques, the mystery of what these black boxes might contain is somewhat alleviated. This classroom-tested

  4. 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

    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 Joaquin Valley contributing most of the CH4 and much of the measured N2O at Bakersfield. Agriculture is observed to provide another major source of N2O, while vehicle emissions are found to be an insignificant source of N2O, contrary to the current statewide greenhouse gas inventory which includes vehicles as a major source. Our PMF source apportionment also produces an evaporative/fugitive factor but its relative lack of CH4 contributions points to removal processes from vented emissions in the surrounding O&G industry and the overwhelming dominance of the dairy CH4 source. In the CABERNET experiments, we report enhancements of CH4 from a number of sources spread across the spatial domain of the Central Valley that improves our understanding of their distribution and relative strengths. We observe large enhancements of CH4 mixing ratios over the dairy and feedlot intensive regions of Central Valley corresponding with significant flux estimates that are larger than CH4 emission rates reported in the greenhouse

  5. Source apportionment of fine particles and its chemical components over the Yangtze River Delta, China during a heavy haze pollution episode

    Science.gov (United States)

    Li, L.; An, J. Y.; Zhou, M.; Yan, R. S.; Huang, C.; Lu, Q.; Lin, L.; Wang, Y. J.; Tao, S. K.; Qiao, L. P.; Zhu, S. H.; Chen, C. H.

    2015-12-01

    An extremely high PM2.5 pollution episode occurred over the eastern China in January 2013. In this paper, the particulate matter source apportionment technology (PSAT) method coupled within the Comprehensive air quality model with extensions (CAMx) is applied to study the source contributions to PM2.5 and its major components at six receptors (Urban Shanghai, Chongming, Dianshan Lake, Urban Suzhou, Hangzhou and Zhoushan) in the Yangtze River Delta (YRD) region. Contributions from 4 source areas (including Shanghai, South Jiangsu, North Zhejiang and Super-region) and 9 emission sectors (including power plants, industrial boilers and kilns, industrial processing, mobile source, residential, volatile emissions, dust, agriculture and biogenic emissions) to PM2.5 and its major components (sulfate, nitrate, ammonia, organic carbon and elemental carbon) at the six receptors in the YRD region are quantified. Results show that accumulation of local pollution was the largest contributor during this air pollution episode in urban Shanghai (55%) and Suzhou (46%), followed by long-range transport (37% contribution to Shanghai and 44% to Suzhou). Super-regional emissions play an important role in PM2.5 formation at Hangzhou (48%) and Zhoushan site (68%). Among the emission sectors contributing to the high pollution episode, the major source categories include industrial processing (with contributions ranging between 12.7 and 38.7% at different receptors), combustion source (21.7-37.3%), mobile source (7.5-17.7%) and fugitive dust (8.4-27.3%). Agricultural contribution is also very significant at Zhoushan site (24.5%). In terms of the PM2.5 major components, it is found that industrial boilers and kilns are the major source contributor to sulfate and nitrate. Volatile emission source and agriculture are the major contributors to ammonia; transport is the largest contributor to elemental carbon. Industrial processing, volatile emissions and mobile source are the most significant

  6. 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

  7. Analytical detection methods for irradiated foods

    International Nuclear Information System (INIS)

    The present publication is a review of scientific literature on the analytical identification of foods treated with ionizing radiation and the quantitative determination of absorbed dose of radiation. Because of the extremely low level of chemical changes resulting from irradiation or because of the lack of specificity to irradiation of any chemical changes, a few methods of quantitative determination of absorbed dose have shown promise until now. On the other hand, the present review has identified several possible methods, which could be used, following further research and testing, for the identification of irradiated foods. An IAEA Co-ordinated Research Programme on Analytical Detection Methods for Irradiation Treatment of Food ('ADMIT'), established in 1990, is currently investigating many of the methods cited in the present document. Refs and tab

  8. IMPROVED SOURCE APPORTIONMENT AND SPECIATION OF LOW-VOLUME PARTICULATE MATTER SAMPLES

    Science.gov (United States)

    This research will examine methods with the high sensitivity and low limits of detection needed to analyze a wide range of chemical species in particulate matter collected with personal samplers. Dr. Schauer and colleagues will develop sensitive methods to detect trace meta...

  9. Nuclear analytical methods for platinum group elements

    International Nuclear Information System (INIS)

    Platinum group elements (PGE) are of special interest for analytical research due to their economic importance like chemical peculiarities as catalysts, medical applications as anticancer drugs, and possible environmental detrimental impact as exhaust from automobile catalyzers. Natural levels of PGE are so low in concentration that most of the current analytical techniques approach their limit of detection capacity. In addition, Ru, Rh, Pd, Re, Os, Ir, and Pt analyses still constitute a challenge in accuracy and precision of quantification in natural matrices. Nuclear analytical techniques, such as neutron activation analysis, X ray fluorescence, or proton-induced X ray emission (PIXE), which are generally considered as reference methods for many analytical problems, are useful as well. However, due to methodological restrictions, they can, in most cases, only be applied after pre-concentration and under special irradiation conditions. This report was prepared following a coordinated research project and a consultants meeting addressing the subject from different viewpoints. The experts involved suggested to discuss the issue according to the (1) application, hence, the concentration levels encountered, and (2) method applied for analysis. Each of the different fields of application needs special consideration for sample preparation, PGE pre-concentration, and determination. Additionally, each analytical method requires special attention regarding the sensitivity and sample type. Quality assurance/quality control aspects are considered towards the end of the report. It is intended to provide the reader of this publication with state-of-the-art information on the various aspects of PGE analysis and to advise which technique might be most suitable for a particular analytical problem related to platinum group elements. In particular, many case studies described in detail from the authors' laboratory experience might help to decide which way to go. As in many cases

  10. 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

  11. 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.

  12. 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.

  13. Wavelet Analytical Forecasting Method of Water Consumption

    Institute of Scientific and Technical Information of China (English)

    刘洪波; 张宏伟

    2004-01-01

    A new method of short-term forecasting for water consumption in municipal supply water networks based on wavelet transformation is introduced. By wavelet decomposing commonly used in the signal field, water consumption per hour is decomposed into many series. Trend item, cycle item and random item are separated from the original time series in this way.Then by analyzing, building a model, forecasting every series and composing the results, the forecasting value of the original consumption is received. Simulation results show that this forecasting method is faster and more accurate, of which the error is less than 20%,indicating that the wavelet analytical method is practicable.

  14. Secondary waste minimization in analytical methods

    International Nuclear Information System (INIS)

    The characterization phase of site remediation is an important and costly part of the process. Because toxic solvents and other hazardous materials are used in common analytical methods, characterization is also a source of new waste, including mixed waste. Alternative analytical methods can reduce the volume or form of hazardous waste produced either in the sample preparation step or in the measurement step. The authors are examining alternative methods in the areas of inorganic, radiological, and organic analysis. For determining inorganic constituents, alternative methods were studied for sample introduction into inductively coupled plasma spectrometers. Figures of merit for the alternative methods, as well as their associated waste volumes, were compared with the conventional approaches. In the radiological area, the authors are comparing conventional methods for gross α/β measurements of soil samples to an alternative method that uses high-pressure microwave dissolution. For determination of organic constituents, microwave-assisted extraction was studied for RCRA regulated semivolatile organics in a variety of solid matrices, including spiked samples in blank soil; polynuclear aromatic hydrocarbons in soils, sludges, and sediments; and semivolatile organics in soil. Extraction efficiencies were determined under varying conditions of time, temperature, microwave power, moisture content, and extraction solvent. Solvent usage was cut from the 300 mL used in conventional extraction methods to about 30 mL. Extraction results varied from one matrix to another. In most cases, the microwave-assisted extraction technique was as efficient as the more common Soxhlet or sonication extraction techniques

  15. Study of Cl containing urban aerosol particles by ion beam analytical methods

    International Nuclear Information System (INIS)

    Complete text of publication follows. In the densely populated areas of Europe one of the most important environmental problems is aerosol pollution. Thus one of the main goals of atmospheric research is to determine aerosol sources. In order to identify the origin of the particles, the knowledge of the chemical composition and size distribution is demanded. As a result of a source apportionment study, several sources of fine (particles with aerodynamic diameter < 2.5 μm) and coarse (10 μm ≥ aerodynamic diameter ≥ 2.5 μm) urban particulate matter were identified in Debrecen, using the hourly evolution of the elemental components. Sources characterized by high chlorine content were found in both size fractions, which gave significant contribution to the aerosol concentration in Debrecen. However, the origin of these particles could not be identified on the available information. In this work we give a more accurate characterization of the sources of coarse-mode Cl by using single particle analysis. Aerosol samples with 2-3 hours time resolution were collected in the frame of sampling campaigns in the garden of ATOMKI between October 2007 and January 2009. The elemental composition (for Z ≥ 13) was determined by Particle Induced X-ray Emission (PIXE). Single particle analysis of chosen samples was done on the ATOMKI Scanning Nuclear Microprobe Facility. Morphology, size and elemental composition for Z ≥ 6 of around 1000 coarse mode particles were determined by Scanning Transmission Ion Microscopy, light element PIXE and PIXE analytical methods. Hierarchical cluster analysis was performed on the data set to group the particles. In order to determine the possible sources of Cl in the coarse mode, the correlation between Cl and other elements, which could be used as tracers of different sources, was examined. Cl showed very strong correlation with Na. However the Cl:Na ratio was found to be different for different episodes indicating different origin of these

  16. Analytical crashworthiness methods applied to composite structures

    OpenAIRE

    Lehnhardt, Keith W.

    1999-01-01

    CIVINS Several shell deformation models are developed for use in crashworthiness analysis of rotationally symmetric structures. These models use analytical techniques to predict the crushing force versus axial crush distance characteristics of both a rigid-plastic, hemispherical shell and an elastic, cylindrical shell loaded axially by a rigid flat plate. Additional methods are proposed to determine the effects of cutout sections and internal stiffening members on the crushing force capaci...

  17. 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

    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......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...... revealed a mixture with high proportions of high-molecular-weight PAHs, indicating a pyrogenic/weathered petrogenic source. Samples from Hendijan coast contained low relative concentrations of PAHs, thus only little information on pollution sources....

  18. 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.

  19. 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.

  20. 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

  1. Application of Receptor Models on Water Quality Data in Source Apportionment in Kuantan River Basin

    Directory of Open Access Journals (Sweden)

    Mohd Fahmi Mohd Nasir

    2012-12-01

    Full Text Available Recent techniques in the management of surface river water have been expanding the demand on the method that can provide more representative of multivariate data set. A proper technique of the architecture of artificial neural network (ANN model and multiple linear regression (MLR provides an advance tool for surface water modeling and forecasting. The development of receptor model was applied in order to determine the major sources of pollutants at Kuantan River Basin, Malaysia. Thirteen water quality parameters were used in principal component analysis (PCA and new variables of fertilizer waste, surface runoff, anthropogenic input, chemical and mineral changes and erosion are successfully developed for modeling purposes. Two models were compared in terms of efficiency and goodness-of-fit for water quality index (WQI prediction. The results show that APCS-ANN model gives better performance with high R2 value (0.9680 and small root mean square error (RMSE value (2.6409 compared to APCS-MLR model. Meanwhile from the sensitivity analysis, fertilizer waste acts as the dominant pollutant contributor (59.82% to the basin studied followed by anthropogenic input (22.48%, surface runoff (13.42%, erosion (2.33% and lastly chemical and mineral changes (1.95%. Thus, this study concluded that receptor modeling of APCS-ANN can be used to solve various constraints in environmental problem that exist between water distribution variables toward appropriate water quality management.

  2. 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.

  3. 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

  4. Chemical composition and source apportionment of aerosol over the Klang valley

    International Nuclear Information System (INIS)

    This paper reports the study of aerosol chemical composition of fine particles (PM 2.5) and possible sources of air pollution over the Klang Valley, Kuala Lumpur, based on the samples collected for a period of 6 years from July 2000 to Jun 2006. Samples collected were measured for mass, black carbon and elemental content of Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Br and Pb. The fine aerosol mass concentration ranged from 11 - 110 ?g/m3. Black carbon is the major component of the fine aerosol with the weight fraction of 20%, whilst S is the major elemental content with the weight fraction about 5% as relative to the fine particle mass. The factor analysis method, positive matrix factorization (PMF) was then used to confirm the possible sources. The result of PMF analysis produced five-factor sources that contribute to the fine particles in the Klang Valley area. The five factors represent sea spray, industry, motor vehicles, smoke and soil. Motor vehicle is the main source of particulates in the area, with an average contribution of 51% of the fine mass concentration, followed by industry, smoke, sea spray and soil, with average contribution of 28%, 14%, 3.6% and 2.1%, respectively. (Author)

  5. Source apportionment of PM10 mass and particulate carbon in the Kathmandu Valley, Nepal

    Science.gov (United States)

    Kim, Bong Mann; Park, Jin-Soo; Kim, Sang-Woo; Kim, Hyunjae; Jeon, Haeun; Cho, Chaeyoon; Kim, Ji-Hyoung; Hong, Seungkyu; Rupakheti, Maheswar; Panday, Arnico K.; Park, Rokjin J.; Hong, Jihyung; Yoon, Soon-Chang

    2015-12-01

    The Kathmandu Valley in Nepal is a bowl-shaped urban basin in the Himalayan foothills with a serious problem of fine particulate air pollution that impacts local health and impairs visibility. Particulate carbon concentrations have reached severe levels that threaten the health of 3.5 million local residents. Moreover, snow and ice on the Himalayan mountains are melting as a result of additional warming due to particulate carbon, especially high black carbon concentrations. To date, the sources of the Valley's particulate carbon and the impacts of different sources on particulate carbon concentrations are not well understood. Thus, before an effective control strategy can be developed, these particulate carbon sources must be identified and quantified. Our study has found that the four primary sources of particulate carbon in the Kathmandu Valley during winter are brick kilns, motor vehicles, fugitive soil dust, and biomass/garbage burning. Their source contributions are quantified using a recently developed new multivariate receptor model SMP. In contrast to other highly polluted areas such as China, secondary contribution is almost negligible in Kathmandu Valley. Brick kilns (40%), motor vehicles (37%) and biomass/garbage burning (22%) have been identified as the major sources of elemental carbon (black carbon) in the Kathmandu Valley during winter, while motor vehicles (47%), biomass/garbage burning (32%), and soil dust (13%) have been identified as the most important sources of organic carbon. Our research indicates that controlling emissions from motor vehicles, brick kilns, biomass/garbage burning, and soil dust is essential for the mitigation of the particulate carbon that threatens public health, impairs visibility, and influences climate warming within and downwind from the Kathmandu Valley. In addition, this paper suggests several useful particulate carbon mitigation methods that can be applied to Kathmandu Valley and other areas in South Asia with

  6. Chemical characterization and source apportionment of fine and coarse particulate matter in Lahore, Pakistan

    Science.gov (United States)

    Stone, Elizabeth; Schauer, James; Quraishi, Tauseef A.; Mahmood, Abid

    2010-03-01

    Lahore, Pakistan is an emerging megacity that is heavily polluted with high levels of particle air pollution. In this study, respirable particulate matter (PM 2.5 and PM 10) were collected every sixth day in Lahore from 12 January 2007 to 19 January 2008. Ambient aerosol was characterized using well-established chemical methods for mass, organic carbon (OC), elemental carbon (EC), ionic species (sulfate, nitrate, chloride, ammonium, sodium, calcium, and potassium), and organic species. The annual average concentration (±one standard deviation) of PM 2.5 was 194 ± 94 μg m -3 and PM 10 was 336 ± 135 μg m -3. Coarse aerosol (PM 10-2.5) was dominated by crustal sources like dust (74 ± 16%, annual average ± one standard deviation), whereas fine particles were dominated by carbonaceous aerosol (organic matter and elemental carbon, 61 ± 17%). Organic tracer species were used to identify sources of PM 2.5 OC and chemical mass balance (CMB) modeling was used to estimate relative source contributions. On an annual basis, non-catalyzed motor vehicles accounted for more than half of primary OC (53 ± 19%). Lesser sources included biomass burning (10 ± 5%) and the combined source of diesel engines and residual fuel oil combustion (6 ± 2%). Secondary organic aerosol (SOA) was an important contributor to ambient OC, particularly during the winter when secondary processing of aerosol species during fog episodes was expected. Coal combustion alone contributed a small percentage of organic aerosol (1.9 ± 0.3%), but showed strong linear correlation with unidentified sources of OC that contributed more significantly (27 ± 16%). Brick kilns, where coal and other low quality fuels are burned together, are suggested as the most probable origins of unapportioned OC. The chemical profiling of emissions from brick kilns and other sources unique to Lahore would contribute to a better understanding of OC sources in this megacity.

  7. ANALYTICAL METHOD VALIDATION: AN UPDATED REVIEW

    Directory of Open Access Journals (Sweden)

    G. Lavanya, M. Sunil, M.M. Eswarudu*, M. C. Eswaraiah, K. Harisudha and B. Naga Spandana

    2013-04-01

    Full Text Available ABSTRACT: The development of sound Analytical method(s is of supreme importance during the process of drug discovery, release to market and development, culminating in a marketing approval. The objective of this paper is to review the method development, optimize and validation of the method for the drug product from the developmental stage of the formulation to commercial batch of the product. Method development for the interested component in finished product or in process tests and the sample preparation of drug product and to provide practical approaches for determining selectivity, specificity, limit of detection, limit of quantitation, linearity, range accuracy, precision, recovery solution stability, ruggedness, and robustness of liquid chromatographic methods to support the Routine, in process and stability analysis.

  8. Comparison of nuclear analytical methods with competitive methods

    International Nuclear Information System (INIS)

    The use of nuclear analytical techniques, especially neutron activation analysis, already have a 50 year old history. Today several sensitive and accurate, non-nuclear trace element analytical techniques are available and new methods are continuously developed. The IAEA is supporting the development of nuclear analytical laboratories in its Member States. In order to be able to advise the developing countries which methods to use in different applications, it is important to know the present status and development trends of nuclear analytical methods, what are their benefits, drawbacks and recommended fields of application, compared with other, non-nuclear techniques. In order to get an answer to these questions the IAEA convened this Advisory Group Meeting. This volume is the outcome of the presentations and discussions of the meeting. A separate abstract was prepared for each of the 21 papers. Refs, figs, tabs

  9. 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

  10. 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

  11. 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

  12. 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

  13. 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.

  14. Modern methods in analytical acoustics lecture notes

    CERN Document Server

    Crighton, D G; Williams, J E Ffowcs; Heckl, M; Leppington, F G

    1992-01-01

    Modern Methods in Analytical Acoustics considers topics fundamental to the understanding of noise, vibration and fluid mechanisms. The series of lectures on which this material is based began by some twenty five years ago and has been developed and expanded ever since. Acknowledged experts in the field have given this course many times in Europe and the USA. Although the scope of the course has widened considerably, the primary aim of teaching analytical techniques of acoustics alongside specific areas of wave motion and unsteady fluid mechanisms remains. The distinguished authors of this volume are drawn from Departments of Acoustics, Engineering of Applied Mathematics in Berlin, Cambridge and London. Their intention is to reach a wider audience of all those concerned with acoustic analysis than has been able to attend the course.

  15. Directory of Analytical Methods, Department 1820

    Energy Technology Data Exchange (ETDEWEB)

    Whan, R.E. (ed.)

    1986-01-01

    The Materials Characterization Department performs chemical, physical, and thermophysical analyses in support of programs throughout the Laboratories. The department has a wide variety of techniques and instruments staffed by experienced personnel available for these analyses, and we strive to maintain near state-of-the-art technology by continued updates. We have prepared this Directory of Analytical Methods in order to acquaint you with our capabilities and to help you identify personnel who can assist with your analytical needs. The descriptions of the various capabilities are requester-oriented and have been limited in length and detail. Emphasis has been placed on applications and limitations with notations of estimated analysis time and alternative or related techniques. A short, simplified discussion of underlying principles is also presented along with references if more detail is desired. The contents of this document have been organized in the order: bulky analysis, microanalysis, surface analysis, optical and thermal property measurements.

  16. Directory of Analytical Methods, Department 1820

    International Nuclear Information System (INIS)

    The Materials Characterization Department performs chemical, physical, and thermophysical analyses in support of programs throughout the Laboratories. The department has a wide variety of techniques and instruments staffed by experienced personnel available for these analyses, and we strive to maintain near state-of-the-art technology by continued updates. We have prepared this Directory of Analytical Methods in order to acquaint you with our capabilities and to help you identify personnel who can assist with your analytical needs. The descriptions of the various capabilities are requester-oriented and have been limited in length and detail. Emphasis has been placed on applications and limitations with notations of estimated analysis time and alternative or related techniques. A short, simplified discussion of underlying principles is also presented along with references if more detail is desired. The contents of this document have been organized in the order: bulky analysis, microanalysis, surface analysis, optical and thermal property measurements

  17. SELECTION OF ONLINE SHOPPING SITE BASED ON ANALYTIC HIERARCHY PROCESS AND ANALYTIC NETWORK PROCESS METHODS

    OpenAIRE

    ÖMÜRBEK, Nuri; ŞİMŞEK, Ali

    2014-01-01

    Analytic Hierarchy Process and Analytic Network Process are common multi criteria decision-making methods. Analytic Hierarchy Process identifies the degree of importance of effective decision making criteria and ranks decision alternatives by making pairwise comparisons. Analytic Network Process, however, identifies the relationship and its direction between the criteria and the alternatives in order to solve problems in a network. In this study, Analytic Hierarchy Process and Analytic Networ...

  18. An inverse and analytic lens design method

    CERN Document Server

    Lu, Yang

    2016-01-01

    Traditional lens design is a numerical and forward process based on ray tracing and aberration theory. This method has limitations because the initial configuration of the lens has to be specified and the aberrations of the lenses have to considered. This paper is an initial attempt to investigate an analytic and inverse lens design method, called Lagrange, to overcome these barriers. Lagrange method tries to build differential equations in terms of the system parameters and the system input and output (object and image). The generalized Snell's law in three dimensional space and the normal of a surface in fundamental differential geometry are applied. Based on the Lagrange method equations for a single surface system are derived which can perfectly image a point object.

  19. Source apportionment and pollution evaluation of heavy metals in water and sediments of Buriganga River, Bangladesh, using multivariate analysis and pollution evaluation indices.

    Science.gov (United States)

    Bhuiyan, Mohammad Amir Hossain; Dampare, Samuel B; Islam, M A; Suzuki, Shigeyuki

    2015-01-01

    Concentrations of heavy metals in water and sediment samples of Buriganga River in the capital city Dhaka, Bangladesh, were studied to understand the level of heavy metals and their source apportionment. The results showed that the mean concentrations of heavy metals both in water and sediment samples were very high and, in most cases, exceeded the permissible limits recommended by the Bangladesh government and other international organizations. Significantly higher concentrations of Pb, Cr, Mn, Co, Ni, Cu, Zn, As, and Cd were found in sediment samples. However, average concentrations of metals both in water and sediment samples were above the effect range median. The heavy metal pollution index (HPI) and degree of contamination (Cd) yielded different results in water samples despite significant correlations between them. The heavy metal evaluation index (HEI) showed strong correlations with HPI and Cd and provided better assessment of pollution levels. The enrichment factor (EF) and geoaccumulation index (Igeo) showed the elevated value of Cr, Pb, and Cd in access of background values. The measured elements were subjected to positive matrix factorization (PMF) and examining correlations in order to explain the content, behavior, and source apportionment of metals. PMF resulted in a successful partitioning of variances into sources related to background geochemistry and contaminant influences. However, the PMF approach successfully demarcated the major sources of metals from tannery, paint, municipal sewage, textiles, and agricultural activities. PMID:25416128

  20. The Emergence of the Analytical Method

    DEFF Research Database (Denmark)

    Plum, Maja

    2012-01-01

    accountability, visibility and documentation. It is argued that pedagogy is generated as a sequential and unit-specified way of working on the production of ‘the learning child’, forming a time- and material-optimising approach. Hereby, the nursery teacher, as a daily scientific researcher, comes to serve the...... nation by an ongoing observational intervention, producing the learning foundation for the entrepreneurial citizen, and thus the nation as a knowledge society in a globalised world. This is what this article terms the emergence of the analytical method....

  1. Analytical Methods for Uranium Concentration Measurements

    International Nuclear Information System (INIS)

    A survey of analytical procedures for the determination of uranium, as performed for NMM in the United States of America, is presented. Methods are outlined for the measurement of the element in a variety of materials, i.e. ores, concentrates, uranium metal, alloys, ceramics, compounds of uranium, scrap processing solutions, residues, and waste stream products. It is not intended as a complete résumé dealing with the subject, but it does offer measurement methods believed to give precise and accurate results of a high order. Because of the monetary value of the materials, and the transfer activities from one installation to another, involving payments or credits, burn-up charges, use charges, etc., it is essential that such methods are used. Methods of analysis to a large extent are dictated by the types of material to be analysed. The use of gravimetric methods are reviewed pertaining to product materials, which are generally defined as uranium metal, or compounds of the metal, such as oxides, halides, or nitrates. A pyro-hydrolysis technique is included under this heading. Non-volatile metallic impurities are determined spectroscopically, and the gravimetric results are corrected accordingly. Volumetric procedures, the ''workhorse'' methods for determining uranium, are thoroughly explored. The technique is applicable to all types of material, providing the uranium available for measurement is present in milligram quantities. Due to the valence states of uranium, reduction-oxidation schemes are particularly attractive. Dissolution problems, separation of interfering elements, reduction steps, and oxidation titrations of reduced uranium are discussed. The application of certain spectrophotometric and fluorometric procedures for analysing low-grade materials are included. Various separation steps incorporated in the procedures before the determination of uranium are reviewed. Along these lines the utilization of differential colorimetry is examined for determining

  2. The analytic nodal method in cylindrical geometry

    International Nuclear Information System (INIS)

    Nodal diffusion methods have been used extensively in nuclear reactor calculations, specifically for their performance advantage, but also for their superior accuracy. More specifically, the Analytic Nodal Method (ANM), utilising the transverse integration principle, has been applied to numerous reactor problems with much success. In this work, a nodal diffusion method is developed for cylindrical geometry. Application of this method to three-dimensional (3D) cylindrical geometry has never been satisfactorily addressed and we propose a solution which entails the use of conformal mapping. A set of 1D-equations with an adjusted, geometrically dependent, inhomogeneous source, is obtained. This work describes the development of the method and associated test code, as well as its application to realistic reactor problems. Numerical results are given for the PBMR-400 MW benchmark problem, as well as for a 'cylindrisized' version of the well-known 3D LWR IAEA benchmark. Results highlight the improved accuracy and performance over finite-difference core solutions and investigate the applicability of nodal methods to 3D PBMR type problems. Results indicate that cylindrical nodal methods definitely have a place within PBMR applications, yielding performance advantage factors of 10 and 20 for 2D and 3D calculations, respectively, and advantage factors of the order of 1000 in the case of the LWR problem

  3. Numerical methods: Analytical benchmarking in transport theory

    International Nuclear Information System (INIS)

    Numerical methods applied to reactor technology have reached a high degree of maturity. Certainly one- and two-dimensional neutron transport calculations have become routine, with several programs available on personal computer and the most widely used programs adapted to workstation and minicomputer computational environments. With the introduction of massive parallelism and as experience with multitasking increases, even more improvement in the development of transport algorithms can be expected. Benchmarking an algorithm is usually not a very pleasant experience for the code developer. Proper algorithmic verification by benchmarking involves the following considerations: (1) conservation of particles, (2) confirmation of intuitive physical behavior, and (3) reproduction of analytical benchmark results. By using today's computational advantages, new basic numerical methods have been developed that allow a wider class of benchmark problems to be considered

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

    Directory of Open Access Journals (Sweden)

    S. L. Tian

    2015-03-01

    Full Text Available 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

  5. Characteristics and source apportionment of organic matter in PM(2.5) from cities in different climatic zones of China

    Science.gov (United States)

    Feng, Jialiang

    For the first time, the dependency of the characteristics of organic matter in PM2.5 on geographical and climatic zones in three metropolitan cities of China was studied. Seasonal samples were collected at suburban and urban sites in Beijing, Shanghai and Guangzhou in 2002 and 2003. To further support the above study, seasonal samples were also collected at Changdao Island, a remote island, in Bohai Sea/Yellow Sea. Concentrations of organic carbon (OC), elemental carbon (EC), water-soluble organic carbon (WSOC), and solvent-extractable organic compounds (SEOC) were analyzed. The characteristics of the n-alkanes, polycyclic aromatic hydrocarbons, n-fatty acids, n-alkanols and molecular markers such as triterpanes were determined and used for source identification. Source apportionment was complemented by Chemical Mass Balance (CMB) modeling using the measured organic species as tracers. The impact of wind speed and wind direction on air quality was studied by back trajectory calculations and analysis. In general, traffic emissions were the largest contributors of OC followed by coal burning, kitchen emissions, vegetative detritus and biomass burning. However, in the space-heating season in Northern China, coal burning was the most important contributor of OC in the suburban areas of Beijing and at Changdao. Beijing had the highest concentration of organic aerosol followed by Guangzhou and Shanghai, while seasonal variation was in reverse order. Dispersion conditions determined by local topographies and meteorology were responsible for this trend. Contrary to common understanding, pollutant concentrations at the suburban sites were higher than the urban sites in all three cities. The main reason was the rapid urbanization of the suburban areas in the immediate vicinity of urban centers since China opened up for economic development, in addition, large numbers of manufacturing plants were relocated from the cities to the countryside in an attempt to clean up the urban

  6. 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

  7. 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

  8. 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

  9. Source apportionment of submicron organic aerosol at an urban background and a road site in Barcelona, Spain

    Directory of Open Access Journals (Sweden)

    M. Alier

    2013-04-01

    Full Text Available This study investigates the contribution of potential sources to the sub-micron (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. 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, 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, Urban POA contributed for 43% (1.5 μg OC m−3 and 18% (0.4 μg OC m−3 to OA in 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. 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, 16% and 7%, at UB and RS, respectively. By contrast, a SOA biogenic component attributed to

  10. Analytical methods to assess nanoparticle toxicity.

    Science.gov (United States)

    Marquis, Bryce J; Love, Sara A; Braun, Katherine L; Haynes, Christy L

    2009-03-01

    During the past 20 years, improvements in nanoscale materials synthesis and characterization have given scientists great control over the fabrication of materials with features between 1 and 100 nm, unlocking many unique size-dependent properties and, thus, promising many new and/or improved technologies. Recent years have found the integration of such materials into commercial goods; a current estimate suggests there are over 800 nanoparticle-containing consumer products (The Project on Emerging Nanotechnologies Consumer Products Inventory, , accessed Oct. 2008), accounting for 147 billion USD in products in 2007 (Nanomaterials state of the market Q3 2008: stealth success, broad impact, Lux Research Inc., New York, NY, 2008). Despite this increase in the prevalence of engineered nanomaterials, there is little known about their potential impacts on environmental health and safety. The field of nanotoxicology has formed in response to this lack of information and resulted in a flurry of research studies. Nanotoxicology relies on many analytical methods for the characterization of nanomaterials as well as their impacts on in vitro and in vivo function. This review provides a critical overview of these techniques from the perspective of an analytical chemist, and is intended to be used as a reference for scientists interested in conducting nanotoxicological research as well as those interested in nanotoxicological assay development. PMID:19238274

  11. 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

  12. 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

  13. 77 FR 41336 - Analytical Methods Used in Periodic Reporting

    Science.gov (United States)

    2012-07-13

    ... 39 CFR Part 3050 Analytical Methods Used in Periodic Reporting AGENCY: Postal Regulatory Commission... initiate an informal rulemaking proceeding to consider changes in analytical methods used in periodic... the Commission initiate an informal rulemaking proceeding to consider changes in the...

  14. 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

  15. 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

  16. 40 CFR 161.180 - Enforcement analytical method.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Enforcement analytical method. 161.180 Section 161.180 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS... § 161.180 Enforcement analytical method. An analytical method suitable for enforcement purposes must...

  17. 40 CFR 158.355 - Enforcement analytical method.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Enforcement analytical method. 158.355... DATA REQUIREMENTS FOR PESTICIDES Product Chemistry § 158.355 Enforcement analytical method. An analytical method suitable for enforcement purposes must be provided for each active ingredient in...

  18. 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

  19. 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.

  20. 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.

  1. Catalyst Kinetics Analytical Method Study of Ruthenium

    Institute of Scientific and Technical Information of China (English)

    Kou ming-ze; Zhan hui-ying; Kou zong-yan

    2004-01-01

    Color reactions are used to determine ruthenium utilizing spectrophotometer, but the process need high temperature, long time pyrogenation and miscellaneous extraction and it contaminates the enviroment. As the sensitive degree and simple apparatus of catalyst kinetics analytical method, it was extensively attentcd. The fundmental principle means to determinn a certain chemistry reaction rate accelerated by homogeneous catalyst and determine substantial content using the function of the numerical value of of its and the catalyst concentration. Color acid double azo-reagents (chloro-phosphor group, arsenic group and carboxylic acid group) are sensitive color reagent determining uranium and thorium of lanthanon, but the report is few that it is used to determine ruthenium. Since 1990s, the author studied that the ruthenium was possessed evident catalysis to the fade reaction of oxidant (KIO4, KBrO3) oxidating color acid double azo-reagent in acitidy medium and provided the catalyst kinetics analytical method to determine trace ruthenium.sensitive degree was increased 1 ~2 amount than color reaction. The reaction as:The original concentration of color acid double azo-reagents is A. The instantaneous absorbency after t reaction time is At. In homogeneous catalyst reaction: log(A0/At) = KCRu3+t. Reaction time t is invarible, so log(A0/At) = K' CRu3+t.Color acid double azo-reagents, such as: chlor-azochlorphosphor(CPA-TC),bromic-azochlorphosphor (CPA-TB), DBS-azochlorphosphor(DBS-CPA), DBC-azochlorphosphor (DBC-CPA), DBOK-azochlorpho sphor (DBOK-CPA), p-iodineazochlorphosphor(CPA-PI),p-acetylazochlorphosphor (CPA-PA), azochlorpho sphorⅢ(CPAⅢ), chlor-azoarsenic (TC-AsA),bromic-azoarsenic (TB-AsA), DBS-azoarsenic(DCS-AsA), DCS-azoarsenic(DCS-AsA),azoarsenicⅢ(AsAⅢ), bromicnityrlazoarsenic (DBN-AsA), P-acetylcarboxy lazo-p,P-acetylcarboxylazo, were utilized in catalyst kinetics system. The author obtains the satisfactory results that color acid double azo-rea gents

  2. Hanford environmental analytical methods: Methods as of March 1990

    International Nuclear Information System (INIS)

    This paper from the analytical laboratories at Hanford describes the method used to measure pH of single-shell tank core samples. Sludge or solid samples are mixed with deionized water. The pH electrode used combines both a sensor and reference electrode in one unit. The meter amplifies the input signal from the electrode and displays the pH visually

  3. 77 FR 56176 - Analytical Methods Used in Periodic Reporting

    Science.gov (United States)

    2012-09-12

    ... 39 CFR Part 3001 Analytical Methods Used in Periodic Reporting AGENCY: Postal Regulatory Commission... Service petition to initiate an informal rulemaking proceeding to consider changes in analytical... consider changes in the analytical methods approved for use in periodic reporting.\\1\\ \\1\\ Petition of...

  4. 40 CFR 136.6 - Method modifications and analytical requirements.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Method modifications and analytical... modifications and analytical requirements. (a) Definitions of terms used in this section. (1) Analyst means the person or laboratory using a test procedure (analytical method) in this Part. (2) Chemistry of the...

  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. Analytical bootstrap methods for censored data

    OpenAIRE

    Alan D. Hutson

    2002-01-01

    Analytic bootstrap estimators for the moments of survival quantities are derived. By using these expressions recommendations can be made as to the appropriateness of bootstrap estimation under censored data conditions.

  7. Analytic methods for calculating coupling impedances

    International Nuclear Information System (INIS)

    These lecture notes describe a variety of analytic techniques to calculate the longitudinal and transverse impedances of obstacles in a beam pipe. They also treat the effort to shield these impedances from the beam by appropriate use of thin conducting layers. (orig.)

  8. 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

  9. Nonlinear ordinary differential equations analytical approximation and numerical methods

    CERN Document Server

    Hermann, Martin

    2016-01-01

    The book discusses the solutions to nonlinear ordinary differential equations (ODEs) using analytical and numerical approximation methods. Recently, analytical approximation methods have been largely used in solving linear and nonlinear lower-order ODEs. It also discusses using these methods to solve some strong nonlinear ODEs. There are two chapters devoted to solving nonlinear ODEs using numerical methods, as in practice high-dimensional systems of nonlinear ODEs that cannot be solved by analytical approximate methods are common. Moreover, it studies analytical and numerical techniques for the treatment of parameter-depending ODEs. The book explains various methods for solving nonlinear-oscillator and structural-system problems, including the energy balance method, harmonic balance method, amplitude frequency formulation, variational iteration method, homotopy perturbation method, iteration perturbation method, homotopy analysis method, simple and multiple shooting method, and the nonlinear stabilized march...

  10. Analytical solution methods for geodesic motion

    CERN Document Server

    Hackmann, Eva

    2015-01-01

    The observation of the motion of particles and light near a gravitating object is until now the only way to explore and to measure the gravitational field. In the case of exact black hole solutions of the Einstein equations the gravitational field is characterized by a small number of parameters which can be read off from the observables related to the orbits of test particles and light rays. Here we review the state of the art of analytical solutions of geodesic equations in various space--times. In particular we consider the four dimensional black hole space--times of Pleba\\'nski--Demia\\'nski type as far as the geodesic equation separates, as well as solutions in higher dimensions, and also solutions with cosmic strings. The mathematical tools used are elliptic and hyperelliptic functions. We present a list of analytic solutions which can be found in the literature.

  11. 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

  12. 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

  13. Analytical method of elements in humic acid phase

    International Nuclear Information System (INIS)

    A method of rapid extraction of humic acid, determination of carbon in the humic acid and a phase analytical method of major relevant elements such as uranium, gold etc, in the humic acid phase are described. Good results are achieved in exploration of hidden uranium ores by using this phase analytical technique

  14. 40 CFR 766.16 - Developing the analytical test method.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Developing the analytical test method. 766.16 Section 766.16 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC... analytical test method. Because of the matrix differences of the chemicals listed for testing, no one...

  15. 40 CFR 425.03 - Sulfide analytical methods and applicability.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Sulfide analytical methods and applicability. 425.03 Section 425.03 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... § 425.03 Sulfide analytical methods and applicability. (a) The potassium ferricyanide titration...

  16. Analytic Methods of Sound Field Synthesis

    CERN Document Server

    Ahrens, Jens

    2012-01-01

    This book treats the topic of sound field synthesis with a focus on serving human listeners though the approach can be also exploited in other areas such as underwater acoustics or ultrasonics. The author derives a fundamental formulation based on standard integral equations and the single-layer potential approach is identified as a useful tool in order to derive a general solution. He also proposes extensions to the single-layer potential approach which allow for a derivation of solutions for non-enclosing distributions of secondary sources such as circular, planar, and linear ones. Based on above described formulation it is shown that the two established analytic approaches of Wave Field Synthesis and Near-field Compensated Higher Order Ambisonics constitute specific solutions to the general problem which are covered by the single-layer potential solution and its extensions. The consequences spatial discretization are analyzed in detail for all elementary geometries of secondary source distributions and app...

  17. Analytical methods for predicting contaminant transport

    International Nuclear Information System (INIS)

    This paper summarizes some of the previous and recent work at the University of California on analytical solutions for predicting contaminate transport in porous and fractured geologic media. Emphasis is given here to the theories for predicting near-field transport, needed to derive the time-dependent source term for predicting far-field transport and overall repository performance. New theories summarized include solubility-limited release rate with flow backfill in rock, near-field transport of radioactive decay chains, interactive transport of colloid and solute, transport of carbon-14 as carbon dioxide in unsaturated rock, and flow of gases out of and a waste container through cracks and penetrations. 28 refs., 4 figs

  18. Characteristics and source apportionment of PM2.5 during a fall heavy haze episode in the Yangtze River Delta of China

    Science.gov (United States)

    Hua, Yang; Cheng, Zhen; Wang, Shuxiao; Jiang, Jingkun; Chen, Daren; Cai, Siyi; Fu, Xiao; Fu, Qingyan; Chen, Changhong; Xu, Bingye; Yu, Jianqiao

    2015-12-01

    Joint field observations were conducted from October to November in 2011 to observe haze pollution in the Yangtze River Delta (YRD), China. Samples of particulate matter with diameter less than 2.5 μm (PM2.5) and less than 10 μm (PM10), gaseous pollutants and meteorology data were collected in five cities - Shanghai, Suzhou, Nanjing, Ningbo and Hangzhou - in the YRD. The chemical composition of PM2.5 was analyzed and the light extinction resulting from each chemical species was calculated using the IMPROVE algorithm. A typical heavy haze episode was selected and the chemical mass balance (CMB) model was applied to identify the sources of PM2.5. The average PM2.5 and PM10 mass concentrations during the haze episode were 100 ± 24 μg/m3 and 164 ± 19 μg/m3, respectively; visibility decreased to 1 km. Organic matter (OM), sulfate, nitrate, and ammonium were the dominant components of PM2.5, accounting for 33%, 19%, 17% and 11% of PM2.5 mass, respectively. Sulfate, OM and nitrate had the highest impact on light extinction, contributing 30%, 28% and 19%, respectively. The source apportionment indicate that PM2.5 is primarily from secondary pollutants and primary emissions from vehicles and biomass burning. A polluted air mass from north Jiangsu Province and stagnant meteorology further aggravated the haze pollution. The five cities had similar characteristics and pollution sources.

  19. Polycyclic aromatic hydrocarbons (PAHs) at traffic and urban background sites of northern Greece: source apportionment of ambient PAH levels and PAH-induced lung cancer risk.

    Science.gov (United States)

    Manoli, Evangelia; Kouras, Athanasios; Karagkiozidou, Olga; Argyropoulos, Georgios; Voutsa, Dimitra; Samara, Constantini

    2016-02-01

    Thirteen particle-phase PAHs, including nine >4-ring congeners [Benz[a]anthracene (BaAn), Chrysene (Chry), Benzo[b]fluoranthene (BbF), Benzo[k]fluoranthene (BkF), Benzo[e]pyrene (BeP), Benzo[a]pyrene (BaP), Dibenzo[a,h]anthracene (dBaAn), Benzo[g,h,i]perylene (BghiPe), Indeno(1,2,3-c,d)pyrene (IP)], listed by IARC (International Agency for Research on Cancer) as class 1, class 2A, and 2B carcinogens, plus four ≤4-ring congeners [Phenanthrene (Ph), Anthracene (An), Fluoranthene (Fl), Pyrene (Py)], were concurrently measured in inhalable and respirable particle fractions (PM10 and PM2.5) at a heavy-traffic and an urban background site in Thessaloniki, northern Greece, during the warm and the cold period of the year. Carcinogenic and mutagenic potencies of the PAH-bearing particles were calculated, and the inhalation cancer risk (ICR) for local population was estimated. Finally, Chemical Mass Balance (CMB) modeling was employed for the source apportionment of ambient PAH levels and the estimated lung cancer risk. Resulted inhalation cancer risk during winter was found to be equivalent in the city center and the urban background area suggesting that residential wood burning may offset the benefits from minor traffic emissions. PMID:26490935

  20. Assessment of water quality in the elbe river at flood water conditions based on cluster analysis, principle components analysis, and source apportionment

    International Nuclear Information System (INIS)

    An assessment of water quality measurements during a spring flood in the Elbe River is presented. Daily samples were taken at a site in the middle Elbe, which is part of the network of the International Commission for the Protection of the Elbe River (IKSE/MKOL). Cluster analysis (CA), principal components analysis (PCA), and source apportionment (APCS apportioning) were used to assess the flood-dependent matter transport. As a result, three main components could be extracted as important to the matter transport in the Elbe River basin during flood events: (i) re-suspended contaminated sediments, which led to temporarily increased concentrations of suspended matter and of most of the investigated heavy metals; (ii) water discharge related concentrations of pedogenic dissolved organic matter (DOM) as well as preliminary diluted concentrations of uranium and chloride, parameters with stable pollution background in the river basin; and (iii) abandoned mines, i.e., their dewatering systems, with particular influence on nickel, manganese, and zinc concentrations. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. 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.

  2. Pharmaceuticals and personal care products (PPCPs) in urban and suburban rivers of Beijing, China: occurrence, source apportionment and potential ecological risk.

    Science.gov (United States)

    Dai, Guohua; Wang, Bin; Fu, Chaochen; Dong, Rui; Huang, Jun; Deng, Shubo; Wang, Yujue; Yu, Gang

    2016-04-20

    This study analyzed 15 pharmaceuticals and personal care products (PPCPs) in two rivers with different urbanization levels in the surrounding watershed (urban and suburb) in Beijing, China. Along the rivers, effluent samples from wastewater treatment plants (WWTPs) and wastewater samples from direct discharge outlets were also collected to reveal their possible contribution to the occurrence of PPCPs in these two rivers. Among the 15 PPCPs, 14 compounds were detected with caffeine (maximum 11 900 ng L(-1)) being the dominant compound. The total concentration of the detected PPCPs in direct discharge outlets (median 4706 ng L(-1)) was much higher than that in river waters (2780 ng L(-1)) and WWTP effluents (1971 ng L(-1)). The suburban-influenced Liangshui River had significantly higher PPCP concentrations compared to the urban-influenced Qing River due to more input of untreated wastewater from direct discharge outlets. Source apportionment showed that approximately 55% of the total PPCPs were contributed by untreated wastewater in the suburban-influenced river. Finally, ecological risk assessment has been regarded as a necessary part of general research. According to the environmental risk assessment results, caffeine, trimethoprim and metoprolol were found to be the most critical compounds, due to their high risk quotient values. The results of the present study can provide useful information for future PPCP pollution control and sustainable water management in Beijing, China. PMID:26985863

  3. 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.

  4. Determination of aluminum by four analytical methods

    International Nuclear Information System (INIS)

    Four procedures have been developed for determining the aluminum concentration in basic matrices. Atomic Absorption Spectroscopy (AAS) was the routine method of analysis. Citrate was required to complex the aluminum and eliminate matrix effects. AAS was the least accurate of the four methods studied and was adversely affected by high aluminum concentrations. The Fluoride Electrode Method was the most accurate and precise of the four methods. A Gran's Plot determination was used to determine the end point and average standard recovery was 100% +- 2%. The Thermometric Titration Method was the fastest method for determining aluminum and could also determine hydroxide concentration at the same time. Standard recoveries were 100% +- 5%. The pH Electrode Method also measures aluminum and hydroxide content simultaneously, but is less accurate and more time consuming that the thermal titration. Samples were analyzed using all four methods and results were compared to determine the strengths and weaknesses of each. On the basis of these comparisons, conclusions were drawn concerning the application of each method to our laboratory needs

  5. Physical analytical methods for uranium hexafluoride

    International Nuclear Information System (INIS)

    Various physical methods of analysis currently used or still under investigation such as: sound analysis, vapor pressure measurements, fractional distillation, cryogenics, micro-sublimation, ultra-violet, visible and infra-red absorption spectrophotometry, nuclear magnetic resonance and mass spectrometry are reviewed. For each method, principle and applications are given, and results obtained concerning reproducibility, application limits and rapidity are discussed. (author)

  6. Advancing Analytical Methods for Characterization of Anionic Carbohydrate Biopolymers

    OpenAIRE

    Langeslay, Derek Joseph

    2013-01-01

    The focus of this dissertation is on the development of improved analytical methods for the characterization of anionic carbohydrate biopolymers. Our goal is to extract important information from complex mixtures of heterogeneous polysaccharides by characterizing their substituent oligosaccharides in terms of monosaccharide composition and primary and secondary structure. This work focuses on the application of two major analytical platforms: spectroscopy and chromatography. The development ...

  7. Optimization of reversed-phase chromatography methods for peptide analytics.

    Science.gov (United States)

    Khalaf, Rushd; Baur, Daniel; Pfister, David

    2015-12-18

    The analytical description and quantification of peptide solutions is an essential part in the quality control of peptide production processes and in peptide mapping techniques. Traditionally, an important tool is analytical reversed phase liquid chromatography. In this work, we develop a model-based tool to find optimal analytical conditions in a clear, efficient and robust manner. The model, based on the Van't Hoff equation, the linear solvent strength correlation, and an analytical solution of the mass balance on a chromatographic column describing peptide retention in gradient conditions is used to optimize the analytical scale separation between components in a peptide mixture. The proposed tool is then applied in the design of analytical reversed phase liquid chromatography methods of five different peptide mixtures. PMID:26620597

  8. Analytical methods for RE-Co alloys

    International Nuclear Information System (INIS)

    Total RE, Co and Fe in mischmetal and its cobalt alloys are determined by visual complexometric methods and instrumental x-ray fluorescence techniques. As Fe causes interference in the determinations of RE and Co and its own determination is affected by the presence of Co, it is removed by precipitation. The iron is determined from the precipitate and RE and Co from the filtrate. Accuracy of the method is checked by analysing synthetic mixtures of RE, Co and Fe. The individual REs in mischmetal are determined by x-ray fluorescence method. The analysis technique is based on comparison of the oxides of the test samples with standards (both in pressed pellet form) in the appropriate composition range. The total RE content of mischmetal determined through complexometric analysis is compared with the total RE determined through x-ray fluorescence. (auth.)

  9. Analytical chemistry methods for boron carbide absorber material. [Standard

    Energy Technology Data Exchange (ETDEWEB)

    DELVIN WL

    1977-07-01

    This standard provides analytical chemistry methods for the analysis of boron carbide powder and pellets for the following: total C and B, B isotopic composition, soluble C and B, fluoride, chloride, metallic impurities, gas content, water, nitrogen, and oxygen. (DLC)

  10. Analytical techniques for instrument design - matrix methods

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, R.A. [Los Alamos National Lab., NM (United States)

    1997-09-01

    We take the traditional Cooper-Nathans approach, as has been applied for many years for steady-state triple-axis spectrometers, and consider its generalisation to other inelastic scattering spectrometers. This involves a number of simple manipulations of exponentials of quadratic forms. In particular, we discuss a toolbox of matrix manipulations that can be performed on the 6- dimensional Cooper-Nathans matrix: diagonalisation (Moller-Nielsen method), coordinate changes e.g. from ({Delta}k{sub I},{Delta}k{sub F} to {Delta}E, {Delta}Q & 2 dummy variables), integration of one or more variables (e.g. over such dummy variables), integration subject to linear constraints (e.g. Bragg`s Law for analysers), inversion to give the variance-covariance matrix, and so on. We show how these tools can be combined to solve a number of important problems, within the narrow-band limit and the gaussian approximation. We will argue that a generalised program that can handle multiple different spectrometers could (and should) be written in parallel to the Monte-Carlo packages that are becoming available. We will also discuss the complementarity between detailed Monte-Carlo calculations and the approach presented here. In particular, Monte-Carlo methods traditionally simulate the real experiment as performed in practice, given a model scattering law, while the Cooper-Nathans method asks the inverse question: given that a neutron turns up in a particular spectrometer configuration (e.g. angle and time of flight), what is the probability distribution of possible scattering events at the sample? The Monte-Carlo approach could be applied in the same spirit to this question.

  11. Analytical techniques for instrument design - matrix methods

    International Nuclear Information System (INIS)

    We take the traditional Cooper-Nathans approach, as has been applied for many years for steady-state triple-axis spectrometers, and consider its generalisation to other inelastic scattering spectrometers. This involves a number of simple manipulations of exponentials of quadratic forms. In particular, we discuss a toolbox of matrix manipulations that can be performed on the 6- dimensional Cooper-Nathans matrix: diagonalisation (Moller-Nielsen method), coordinate changes e.g. from (ΔkI,ΔkF to ΔE, ΔQ ampersand 2 dummy variables), integration of one or more variables (e.g. over such dummy variables), integration subject to linear constraints (e.g. Bragg's Law for analysers), inversion to give the variance-covariance matrix, and so on. We show how these tools can be combined to solve a number of important problems, within the narrow-band limit and the gaussian approximation. We will argue that a generalised program that can handle multiple different spectrometers could (and should) be written in parallel to the Monte-Carlo packages that are becoming available. We will also discuss the complementarity between detailed Monte-Carlo calculations and the approach presented here. In particular, Monte-Carlo methods traditionally simulate the real experiment as performed in practice, given a model scattering law, while the Cooper-Nathans method asks the inverse question: given that a neutron turns up in a particular spectrometer configuration (e.g. angle and time of flight), what is the probability distribution of possible scattering events at the sample? The Monte-Carlo approach could be applied in the same spirit to this question

  12. NUMERICAL AND ANALYTIC METHODS OF ESTIMATION BRIDGES’ CONSTRUCTIONS

    Directory of Open Access Journals (Sweden)

    Y. Y. Luchko

    2010-03-01

    Full Text Available In this article the numerical and analytical methods of calculation of the stressed-and-strained state of bridge constructions are considered. The task on increasing of reliability and accuracy of the numerical method and its solution by means of calculations in two bases are formulated. The analytical solution of the differential equation of deformation of a ferro-concrete plate under the action of local loads is also obtained.

  13. ANALYTICAL METHODS FOR CALCULATING FAN AERODYNAMICS

    Directory of Open Access Journals (Sweden)

    Jan Dostal

    2015-12-01

    Full Text Available This paper presents results obtained between 2010 and 2014 in the field of fan aerodynamics at the Department of Composite Technology at the VZLÚ aerospace research and experimental institute in Prague – Letnany. The need for rapid and accurate methods for the preliminary design of blade machinery led to the creation of a mathematical model based on the basic laws of turbomachine aerodynamics. The mathematical model, the derivation of which is briefly described below, has been encoded in a computer programme, which enables the theoretical characteristics of a fan of the designed geometry to be determined rapidly. The validity of the mathematical model is assessed continuously by measuring model fans in the measuring unit, which was developed and manufactured specifically for this purpose. The paper also presents a comparison between measured characteristics and characteristics determined by the mathematical model as the basis for a discussion on possible causes of measured deviations and calculation deviations.

  14. Analytical instruments, ionization sources, and ionization methods

    Science.gov (United States)

    Atkinson, David A.; Mottishaw, Paul

    2006-04-11

    Methods and apparatus for simultaneous vaporization and ionization of a sample in a spectrometer prior to introducing the sample into the drift tube of the analyzer are disclosed. The apparatus includes a vaporization/ionization source having an electrically conductive conduit configured to receive sample particulate which is conveyed to a discharge end of the conduit. Positioned proximate to the discharge end of the conduit is an electrically conductive reference device. The conduit and the reference device act as electrodes and have an electrical potential maintained between them sufficient to cause a corona effect, which will cause at least partial simultaneous ionization and vaporization of the sample particulate. The electrical potential can be maintained to establish a continuous corona, or can be held slightly below the breakdown potential such that arrival of particulate at the point of proximity of the electrodes disrupts the potential, causing arcing and the corona effect. The electrical potential can also be varied to cause periodic arcing between the electrodes such that particulate passing through the arc is simultaneously vaporized and ionized. The invention further includes a spectrometer containing the source. The invention is particularly useful for ion mobility spectrometers and atmospheric pressure ionization mass spectrometers.

  15. Fracture mechanics life analytical methods verification testing

    Science.gov (United States)

    Favenesi, J. A.; Clemons, T. G.; Riddell, W. T.; Ingraffea, A. R.; Wawrzynek, P. A.

    1994-01-01

    The objective was to evaluate NASCRAC (trademark) version 2.0, a second generation fracture analysis code, for verification and validity. NASCRAC was evaluated using a combination of comparisons to the literature, closed-form solutions, numerical analyses, and tests. Several limitations and minor errors were detected. Additionally, a number of major flaws were discovered. These major flaws were generally due to application of a specific method or theory, not due to programming logic. Results are presented for the following program capabilities: K versus a, J versus a, crack opening area, life calculation due to fatigue crack growth, tolerable crack size, proof test logic, tearing instability, creep crack growth, crack transitioning, crack retardation due to overloads, and elastic-plastic stress redistribution. It is concluded that the code is an acceptable fracture tool for K solutions of simplified geometries, for a limited number of J and crack opening area solutions, and for fatigue crack propagation with the Paris equation and constant amplitude loads when the Paris equation is applicable.

  16. Fracture mechanics life analytical methods verification testing

    Science.gov (United States)

    Favenesi, J. A.; Clemons, T. G.; Riddell, W. T.; Ingraffea, A. R.; Wawrzynek, P. A.

    1994-09-01

    The objective was to evaluate NASCRAC (trademark) version 2.0, a second generation fracture analysis code, for verification and validity. NASCRAC was evaluated using a combination of comparisons to the literature, closed-form solutions, numerical analyses, and tests. Several limitations and minor errors were detected. Additionally, a number of major flaws were discovered. These major flaws were generally due to application of a specific method or theory, not due to programming logic. Results are presented for the following program capabilities: K versus a, J versus a, crack opening area, life calculation due to fatigue crack growth, tolerable crack size, proof test logic, tearing instability, creep crack growth, crack transitioning, crack retardation due to overloads, and elastic-plastic stress redistribution. It is concluded that the code is an acceptable fracture tool for K solutions of simplified geometries, for a limited number of J and crack opening area solutions, and for fatigue crack propagation with the Paris equation and constant amplitude loads when the Paris equation is applicable.

  17. A Probabilistic Method for Certification of Analytically Redundant Systems

    Directory of Open Access Journals (Sweden)

    Hu Bin

    2015-03-01

    Full Text Available Analytical fault detection algorithms have the potential to reduce the size, power and weight of safety-critical aerospace systems. Analytical redundancy has been successfully applied in many non-safety critical applications. However, acceptance for aerospace applications will require new methods to rigorously certify the impact of such algorithms on the overall system reliability. This paper presents a theoretical method to assess the probabilistic performance for an analytically redundant system. Specifically, a fault tolerant actuation system is considered. The system consists of dual-redundant actuators and an analytical fault detection algorithm to switch between the hardware components. The exact system failure rate per hour is computed using the law of total probability. This analysis requires knowledge of the failure rates for the hardware components. In addition, knowledge of specific probabilistic performance metrics for the fault detection logic is needed. Numerical examples are provided to demonstrate the proposed analysis method.

  18. A heterogeneous analytical benchmark for particle transport methods development

    International Nuclear Information System (INIS)

    A heterogeneous analytical benchmark has been designed to provide a quality control measure for large-scale neutral particle computational software. Assurance that particle transport methods are efficiently implemented and that current codes are adequately maintained for reactor and weapons applications is a major task facing today's transport code developers. An analytical benchmark, as used here, refers to a highly accurate evaluation of an analytical solution to the neutral particle transport equation. Because of the requirement of an analytical solution, however, only relatively limited transport scenarios can be treated. To some this may seem to be a major disadvantage of analytical benchmarks. However, to the code developer, simplicity by no means diminishes the usefulness of these benchmarks since comprehensive transport codes must perform adequately for simple as well as comprehensive transport scenarios

  19. [Source Contribution Analysis of the Fine Particles in Shanghai During a Heavy Haze Episode in December, 2013 Based on the Particulate Matter Source Apportionment Technology].

    Science.gov (United States)

    Li, Li; An, Jing-yu; Yan, Ru-sha

    2015-10-01

    The haze pollution caused by high PM2.5 concentrations has become one of the major environmental issues restricting urban and regional sustainable development in China in recent years. Therefore, the diagnosis of the pollution sources of PM2.5 and its major components in a scientific and efficient way is of great significance both scientifically and theoretically. A rare heavy haze pollution event occurred in Shanghai and the surrounding Yangtze River Delta in early December, 2013, that the hourly PM2.5 concentration reached 640 μg x m(-3). In this study, we analyzed the three typical episodes that occurred in Shanghai during this period. The particulate matter source apportionment technology (PSAT) was applied to study the source contributions to PM2.5 and its major components. Results showed that NO3-(2.5) were mostly contributed by industrial boilers and kilns, transportation and power plants. Comparatively, most of the SO4(2-) 2.5 came from industry and transport sectors. During the three episodes including haze, foggy haze and transport, local emissions contributed 35.3%, 44.8%, 22.7%, while super-regional transport accounted for 42.0%, 41.1% and 59.8% to PM2.5, respectively. In the YRD modeling domain, fugitive dust, industrial processing, volatile source, industrial boilers and kilns and transport were the major contributors to high concentrations of PM2.5, with the average contributions of 25.1%, 14.9%, 15.8%, 13.7% and 15.9%, respectively. Results showed that the very heavy haze pollution is usually not caused by a single city, the regional joint pollution control is of great importance to relieve the pollution level. PMID:26841584

  20. 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.

  1. 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.

  2. 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

  3. 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.

  4. 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.

  5. Comparative Analytical Methods for the Measurment of Chlorine Dioxide

    OpenAIRE

    Desai, Unmesh Jeetendra

    2002-01-01

    Four commercially available methods used for the analysis of low-level Chlorine Dioxide (ClO2) concentrations in drinking water were evaluated for accuracy and precision and ranked according to cost, efficiency and ease of the methods under several conditions that might be encountered at water treatment plants. The different analytical methods included: 1.The DPD (N, N-diethyl-p-phenylenediamine) method 2.Lissamine Green B (LGB) wet-chemical method 3.Palintest® kit LGB 4.A...

  6. Statistically qualified neuro-analytic failure detection method and system

    Science.gov (United States)

    Vilim, Richard B.; Garcia, Humberto E.; Chen, Frederick W.

    2002-03-02

    An apparatus and method for monitoring a process involve development and application of a statistically qualified neuro-analytic (SQNA) model to accurately and reliably identify process change. The development of the SQNA model is accomplished in two stages: deterministic model adaption and stochastic model modification of the deterministic model adaptation. Deterministic model adaption involves formulating an analytic model of the process representing known process characteristics, augmenting the analytic model with a neural network that captures unknown process characteristics, and training the resulting neuro-analytic model by adjusting the neural network weights according to a unique scaled equation error minimization technique. Stochastic model modification involves qualifying any remaining uncertainty in the trained neuro-analytic model by formulating a likelihood function, given an error propagation equation, for computing the probability that the neuro-analytic model generates measured process output. Preferably, the developed SQNA model is validated using known sequential probability ratio tests and applied to the process as an on-line monitoring system. Illustrative of the method and apparatus, the method is applied to a peristaltic pump system.

  7. New concept of analytical method for two-phase flow

    International Nuclear Information System (INIS)

    The authors are developing a new analytical method for vertical upward two-phase flow based on a concept that two-phase flow with minimum pressure energy consumption rate is the most stable and easily flowable two-phase flow for the given boundary conditions and, thus, such two-phase flow should be realized actually. Although this concept is applied basically one-dimensionally in the analytical method, gravity convection effect due to density difference between liquid film on the channel wall and two-phase flow core in the central region of the channel is taken into account through a two-dimensional turbulent flow analysis. An air-water two-phase flow experiment was performed to verify the proposed analytical method. In the present paper, results of the experimental analysis with the proposed method are reported. (author)

  8. 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...

  9. ASSESSMENT OF CONSTRUCTION INVESTMENT PROJECTS USING OF ANALYTIC HIERARCHY METHOD

    OpenAIRE

    AYTEKİN, Osman; İlker ÖZDEMİR; KUŞAN, Hakan; TEZCAN, Ömür

    2012-01-01

    In this study, it has been researched the applicability of AHP method (Analytic Hierarchy Method) that is one of multi-criteria decision-making methods, in assessment of construction investment projects. For this aim, it has been considered an application having shopping center, housing estate and residence alternatives. For application of AHP method, a binary comparison matrices have been established using main criteria which have financial conditions, sales and marketing, location and contr...

  10. Beamforming and holography image formation methods: an analytic study.

    Science.gov (United States)

    Solimene, Raffaele; Cuccaro, Antonio; Ruvio, Giuseppe; Tapia, Daniel Flores; O'Halloran, Martin

    2016-04-18

    Beamforming and holographic imaging procedures are widely used in many applications such as radar sensing, sonar, and in the area of microwave medical imaging. Nevertheless, an analytical comparison of the methods has not been done. In this paper, the Point Spread Functions pertaining to the two methods are analytically determined. This allows a formal comparison of the two techniques, and to easily highlight how the performance depends on the configuration parameters, including frequency range, number of scatterers, and data discretization. It is demonstrated that the beamforming and holography basically achieve the same resolution but beamforming requires a cheaper (less sensors) configuration.. PMID:27137336

  11. 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

    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.

  12. 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

  13. [Distribution characteristics and source apportionment of dichloro-diphenyl-tricgloroethanes in Zhangiiang River Estuary of Fujian, China].

    Science.gov (United States)

    Luo, Dong-lian

    2014-12-01

    The concentration, distribution and transfer of dichloro-diphenyl-tricgloroethanes (DDTs) in the surface layer water, sediments and aquatic organisms from the Zhangjiang River Estuary were investigated using GC-ECD method. The possible sources were assessed based on the distribution and composition characteristics of DDTs together with the investigation results of dicofol. The results showed that the concentration of DDTs in surface layer water ranged from ND (not detected) to 20.1 ng x L(-1) with an average of 10.5 ng x L(-1) in dry period, from ND to 45.2 ng +/- L(-1) with an aver- age of 28.3 ng x L(-1) in wet period, and from ND to 18.8 ng x L(-1) with an average of 5.03 ng x L(-1) in level period. Concentration of DDTs in surface sediment (dry mass) ranged from 1.87 ng x g(-1) to 144 ng x g(-1) with an average of 17.3 ng x g(-1), and that in 11 species of aquatic organisms ranged from 1.09 ng x g(-1) to 432 ng x g(-1) with an average of 37.0 ng x g(-1). Compared to other areas, the residues of DDTs in the Zhangjiang River Estuary were at the medium level. The accumulation factors of DDTs in sediment and aquatic organisms were 1185 and 2534, respectively. The capacities for DDTs accumulation were in the order of fish>shellfish>shrimp>aquatic plants. The concentrations of DDTs showed downtrend along the Zhangjiang River, indicating that the residues of DDTs mainly came from terrigenous pollution rather than from the release of antifouling agent of ships. Based on the composition profile, DDTs mainly came from the early residues. However, the highest value of dicofol was recently detected both in the water and sediment of Y8 station, which suggested that new DDTs inputs at the Y8 station might be related to the recent usage of dicofol. PMID:25876421

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

    Science.gov (United States)

    Verma, V.; Fang, T.; Guo, H.; King, L.; Bates, J. T.; Peltier, R. E.; Edgerton, E.; Russell, A. G.; Weber, R. J.

    2014-12-01

    We assess the potential of the water-soluble fraction of atmospheric fine aerosols in the southeastern United States 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 - water-soluble organic carbon) in summer, and biomass burning markers in winter. Redox-active metals were also somewhat 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 (12-25%), while secondary oxidation processes dominated the DTT activity in summer (46%) and biomass burning in winter (47%). Road 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

  15. 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

  16. Radiocarbon analysis of elemental and organic carbon in Switzerland during winter-smog episodes from 2008 to 2012 - Part 1: Source apportionment and spatial variability

    Science.gov (United States)

    Zotter, P.; Ciobanu, V. G.; Zhang, Y. L.; El-Haddad, I.; Macchia, M.; Daellenbach, K. R.; Salazar, G. A.; Huang, R.-J.; Wacker, L.; Hueglin, C.; Piazzalunga, A.; Fermo, P.; Schwikowski, M.; Baltensperger, U.; Szidat, S.; Prévôt, A. S. H.

    2014-12-01

    While several studies have investigated winter-time air pollution with a wide range of concentration levels, hardly any results are available for longer time periods covering several winter-smog episodes at various locations; e.g., often only a few weeks from a single winter are investigated. Here, we present source apportionment results of winter-smog episodes from 16 air pollution monitoring stations across Switzerland from five consecutive winters. Radiocarbon (14C) analyses of the elemental (EC) and organic (OC) carbon fractions, as well as levoglucosan, major water-soluble ionic species and gas-phase pollutant measurements were used to characterize the different sources of PM10. The most important contributions to PM10 during winter-smog episodes in Switzerland were on average the secondary inorganic constituents (sum of nitrate, sulfate and ammonium = 41 ± 15%) followed by organic matter (OM) (34 ± 13%) and EC (5 ± 2%). The non-fossil fractions of OC (fNF,OC) ranged on average from 69 to 85 and 80 to 95% for stations north and south of the Alps, respectively, showing that traffic contributes on average only up to ~ 30% to OC. The non-fossil fraction of EC (fNF,EC), entirely attributable to primary wood burning, was on average 42 ± 13 and 49 ± 15% for north and south of the Alps, respectively. While a high correlation was observed between fossil EC and nitrogen oxides, both primarily emitted by traffic, these species did not significantly correlate with fossil OC (OCF), which seems to suggest that a considerable amount of OCF is secondary, from fossil precursors. Elevated fNF,EC and fNF,OC values and the high correlation of the latter with other wood burning markers, including levoglucosan and water soluble potassium (K+) indicate that residential wood burning is the major source of carbonaceous aerosols during winter-smog episodes in Switzerland. The inspection of the non-fossil OC and EC levels and the relation with levoglucosan and water-soluble K

  17. Radiocarbon analysis of elemental and organic carbon in Switzerland during winter-smog episodes from 2008 to 2012 – Part 1: Source apportionment and spatial variability

    Directory of Open Access Journals (Sweden)

    P. Zotter

    2014-06-01

    Full Text Available While several studies have investigated winter-time air pollution with a wide range of concentration levels, hardly any results are available for longer time periods covering several winter-smog episodes at various locations; e.g. often only a few weeks from a single winter are investigated. Here, we present source apportionment results of winter-smog episodes from 16 air pollution monitoring stations across Switzerland from five consecutive winters. Radiocarbon (14C analyses of the elemental (EC and organic (OC carbon fractions, as well as levoglucosan, major water-soluble ionic species and gas-phase pollutant measurements were used to characterize the different sources of PM10. The most important contributions to PM10 during winter-smog episodes in Switzerland were on average the secondary inorganic constituents (sum of nitrate, sulfate and ammonium = 41 ± 15% followed by organic matter OM (30 ± 12% and EC (5 ± 2%. The non-fossil fractions of OC (fNF,OC ranged on average from 69–85% and 80–95 % for stations north and south of the Alps, respectively, showing that traffic contributes on average only up to ~30% to OC. The non-fossil fraction of EC (fNF,EC, entirely attributable to primary biomass burning, was on average 42 ± 13% and 49 ± 15% for north and south of the Alps, respectively. While a high correlation was observed between fossil EC and nitrogen oxides, both primarily emitted by traffic, these species did not significantly correlate with fossil OC (OCF, which seems to suggest that a considerable amount of OCF is secondary, formed from fossil precursors. Elevated fNF,EC and fNF,OC values and the high correlation of the latter with other wood burning markers, including levoglucosan and water soluble potassium (K+ indicate that biomass burning is the major source of carbonaceous aerosols during winter-smog episodes in Switzerland. The inspection of the non-fossil OC and EC levels and the relation with levoglucosan and water

  18. Source apportionment of PM10 in a north-western Europe regional urban background site (Lens, France) using positive matrix factorization and including primary biogenic emissions

    Science.gov (United States)

    Waked, A.; Favez, O.; Alleman, L. Y.; Piot, C.; Petit, J.-E.; Delaunay, T.; Verlinden, E.; Golly, B.; Besombes, J.-L.; Jaffrezo, J.-L.; Leoz-Garziandia, E.

    2014-04-01

    In this work, the source of ambient particulate matter (PM10) collected over a one-year period at an urban background site in Lens (France) was determined and investigated using a positive matrix factorization receptor model (US EPA PMF v3.0). In addition, a potential source contribution function (PSCF) was performed by means of the Hybrid Single-Particle Lagrangian Integrated Trajectory (Hysplit) v4.9 model to assess prevailing geographical origins of the identified sources. A selective iteration process was followed for the qualification of the more robust and meaningful PMF solution. Components measured and used in the PMF included inorganic and organic species: soluble ionic species, trace elements, elemental carbon (EC), sugar alcohols, sugar anhydride, and organic carbon (OC). The mean PM10 concentration measured from March 2011 to March 2012 was about 21 μg m-3 with typically OM, nitrate and sulfate contributing to most of the mass and accounting respectively for 5.8, 4.5 and 2.3 μg m-3 on a yearly basis. Accordingly, PMF outputs showed that the main emission sources were (in decreasing order of contribution) secondary inorganic aerosols (28% of the total PM10 mass), aged marine emissions (19%), with probably predominant contribution of shipping activities, biomass burning (13%), mineral dust (13%), primary biogenic emissions (9%), fresh sea salts (8%), primary traffic emissions (6%) and heavy oil combustion (4%). Significant temporal variations were observed for most of the identified sources. In particular, biomass burning emissions were negligible in summer but responsible for about 25% of total PM10 and 50% of total OC in wintertime. Conversely, primary biogenic emissions were found to be negligible in winter but to represent about 20% of total PM10 and 40% of total OC in summer. The latter result calls for more investigations of primary biogenic aerosols using source apportionment studies, which quite usually disregard this type of source. This study

  19. Source apportionment of PM10 in a North-Western Europe regional urban background site (Lens, France using Positive Matrix Factorization and including primary biogenic emissions

    Directory of Open Access Journals (Sweden)

    A. Waked

    2013-10-01

    Full Text Available In this work, the source of ambient particulate matter (PM10 collected over a one year period at an urban background site in Lens (France were determined and investigated using a~Positive Matrix Factorization receptor model (US EPA PMF v3.0. In addition, a Potential Source Contribution Function (PSCF was performed by means of the Hysplit v4.9 model to assess prevailing geographical origins of the identified sources. A selective iteration process was followed for the qualification of the more robust and meaningful PMF solution. Components measured and used in the PMF include inorganic and organic species: soluble ionic species, trace elements, elemental carbon (EC, sugars alcohols, sugar anhydride, and organic carbon (OC. The mean PM10 concentration measured from March 2011 to March 2012 was about 21 μg m−3 with typically OM, nitrate and sulfate contributing to most of the mass and accounting respectively for 5.8, 4.5 and 2.3 μg m−3 on a yearly basis. Accordingly, PMF outputs showed that the main emission sources were (in a decreasing order of contribution: secondary inorganic aerosols (28% of the total PM10 mass, aged marine emissions (19%, with probably predominant contribution of shipping activities, biomass burning (13%, mineral dust (13%, primary biogenic emissions (9%, fresh sea salts (8%, primary traffic emissions (6% and heavy oil combustion (4%. Significant temporal variations were observed for most of the identified sources. In particular, biomass burning emissions were negligible in summer but responsible for about 25% of total PM10 and 50% of total OC at wintertime. Conversely, primary biogenic emissions were found to be negligible in winter but to represent about 20% of total PM10 and 40% of total OC in summer. The latter result calls for more investigations of primary biogenic aerosols using source apportionment studies, which quite usually disregards this type of sources. This study furthermore underlines the major influence

  20. 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

  1. 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

  2. A New Analytic Alignment Method for a SINS

    Directory of Open Access Journals (Sweden)

    Caiming Tan

    2015-11-01

    Full Text Available Analytic alignment is a type of self-alignment for a Strapdown inertial navigation system (SINS that is based solely on two non-collinear vectors, which are the gravity and rotational velocity vectors of the Earth at a stationary base on the ground. The attitude of the SINS with respect to the Earth can be obtained directly using the TRIAD algorithm given two vector measurements. For a traditional analytic coarse alignment, all six outputs from the inertial measurement unit (IMU are used to compute the attitude. In this study, a novel analytic alignment method called selective alignment is presented. This method uses only three outputs of the IMU and a few properties from the remaining outputs such as the sign and the approximate value to calculate the attitude. Simulations and experimental results demonstrate the validity of this method, and the precision of yaw is improved using the selective alignment method compared to the traditional analytic coarse alignment method in the vehicle experiment. The selective alignment principle provides an accurate relationship between the outputs and the attitude of the SINS relative to the Earth for a stationary base, and it is an extension of the TRIAD algorithm. The selective alignment approach has potential uses in applications such as self-alignment, fault detection, and self-calibration.

  3. Analytical Evaluation of Beam Deformation Problem Using Approximate Methods

    DEFF Research Database (Denmark)

    Barari, Amin; Kimiaeifar, A.; Domairry, G.

    2010-01-01

    , and this process produces noise in the obtained answers. This paper deals with the solution of second order of differential equation governing beam deformation using four analytical approximate methods, namely the Perturbation, Homotopy Perturbation Method (HPM), Homotopy Analysis Method (HAM) and......The beam deformation equation has very wide applications in structural engineering. As a differential equation, it has its own problem concerning existence, uniqueness and methods of solutions. Often, original forms of governing differential equations used in engineering problems are simplified...... Variational Iteration Method (VIM). The comparisons of the results reveal that these methods are very effective, convenient and quite accurate for systems of non-linear differential equation....

  4. Approximate analytical methods for solving ordinary differential equations

    CERN Document Server

    Radhika, TSL; Rani, T Raja

    2015-01-01

    Approximate Analytical Methods for Solving Ordinary Differential Equations (ODEs) is the first book to present all of the available approximate methods for solving ODEs, eliminating the need to wade through multiple books and articles. It covers both well-established techniques and recently developed procedures, including the classical series solution method, diverse perturbation methods, pioneering asymptotic methods, and the latest homotopy methods.The book is suitable not only for mathematicians and engineers but also for biologists, physicists, and economists. It gives a complete descripti

  5. An analytical software for NAA by using K0-method

    International Nuclear Information System (INIS)

    An analytical software has been designed for a personal computer in DOS environment to do reactor NAA by using K0-method. The system has functions of radionuclide identification, f and α calculation, K0-value calculation, quantitative calculation of elemental concentrations, nuclides' data management, experiment design, computer simulation etc. The analytical methods used in this system include absolute method, relative method and K0-method. Using this system, three gamma-ray spectra for NAA of Au, Zr samples and GBW07107 rock standard sample have been analyzed. The analysis results are in agreement with the certified results in the scope of uncertainties and the f and α values at the irradiation site in the UZrH pulse reactor are 36.6 and 0.044 respectively. (author)

  6. 40 CFR 141.25 - Analytical methods for radioactivity.

    Science.gov (United States)

    2010-07-01

    ... was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part... January 1, 2005 to satisfy the radium-226 and radium-228 monitoring requirements specified at 40 CFR 141... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Analytical methods for...

  7. Frontier in nanoscale flows fractional calculus and analytical methods

    CERN Document Server

    Lewis, Roland; Liu, Hong-yan

    2014-01-01

    This ebook covers the basic properties of nanoscale flows, and various analytical and numerical methods for nanoscale flows and environmental flows. This ebook is a good reference not only for audience of the journal, but also for various communities in mathematics, nanotechnology and environmental science.

  8. Prediction of polymer flooding performance using an analytical method

    International Nuclear Information System (INIS)

    The study investigated the applicability of an analytical method developed by El-Khatib in polymer flooding. Results from a simulator UTCHEM and experiments were compared with the El-Khatib prediction method. In general, by assuming a constant viscosity polymer injection, the method gave much higher recovery values than the simulation runs and the experiments. A modification of the method gave better correlation, albeit only oil production. Investigation is continuing on modifying the method so that a better overall fit can be obtained for polymer flooding. (Author)

  9. Use of scientometrics to assess nuclear and other analytical methods

    Energy Technology Data Exchange (ETDEWEB)

    Lyon, W.S.

    1986-01-01

    Scientometrics involves the use of quantitative methods to investigate science viewed as an information process. Scientometric studies can be useful in ascertaining which methods have been most employed for various analytical determinations as well as for predicting which methods will continue to be used in the immediate future and which appear to be losing favor with the analytical community. Published papers in the technical literature are the primary source materials for scientometric studies; statistical methods and computer techniques are the tools. Recent studies have included growth and trends in prompt nuclear analysis impact of research published in a technical journal, and institutional and national representation, speakers and topics at several IAEA conferences, at modern trends in activation analysis conferences, and at other non-nuclear oriented conferences. Attempts have also been made to predict future growth of various topics and techniques. 13 refs., 4 figs., 17 tabs.

  10. Development and validation of analytical methods for dietary supplements

    International Nuclear Information System (INIS)

    The expanding use of innovative botanical ingredients in dietary supplements and foods has resulted in a flurry of research aimed at the development and validation of analytical methods for accurate measurement of active ingredients. The pressing need for these methods is being met through an expansive collaborative initiative involving industry, government, and analytical organizations. This effort has resulted in the validation of several important assays as well as important advances in the method engineering procedures which have improved the efficiency of the process. The initiative has also allowed researchers to hurdle many of the barricades that have hindered accurate analysis such as the lack of reference standards and comparative data. As the availability for nutraceutical products continues to increase these methods will provide consumers and regulators with the scientific information needed to assure safety and dependable labeling

  11. Use of scientometrics to assess nuclear and other analytical methods

    International Nuclear Information System (INIS)

    Scientometrics involves the use of quantitative methods to investigate science viewed as an information process. Scientometric studies can be useful in ascertaining which methods have been most employed for various analytical determinations as well as for predicting which methods will continue to be used in the immediate future and which appear to be losing favor with the analytical community. Published papers in the technical literature are the primary source materials for scientometric studies; statistical methods and computer techniques are the tools. Recent studies have included growth and trends in prompt nuclear analysis impact of research published in a technical journal, and institutional and national representation, speakers and topics at several IAEA conferences, at modern trends in activation analysis conferences, and at other non-nuclear oriented conferences. Attempts have also been made to predict future growth of various topics and techniques. 13 refs., 4 figs., 17 tabs

  12. Oxcarbazepine: validation and application of an analytical method

    OpenAIRE

    Paula Cristina Rezende Enéas; Renata Barbosa de Oliveira; Gerson Antônio Pianetti

    2010-01-01

    Oxcarbazepine (OXC) is an important anticonvulsant and mood stabilizing drug. A pharmacopoeial monograph for OXC is not yet available and therefore the development and validation of a new analytical method for quantification of this drug is essential. In the present study, a UV spectrophotometric method for the determination of OXC was developed. The various parameters, such as linearity, precision, accuracy and specificity, were studied according to International Conference on Harmonization ...

  13. A certain analytical method used for solving the Stefan problem

    OpenAIRE

    Grzymkowski Radoslaw; Hetmaniok Edyta; Pleszczynski Mariusz; Slota Damian

    2013-01-01

    The paper presents an analytic method applied for finding the approximate solution of Stefan problem reduced to the one-phase solidification problem of a plate with the unknown a priori, varying in time boundary of the region in which the solution is sought. Proposed method is based on the known formalism of initial extension of a sought function describing the field of temperature into the power series, some coefficients of which can be determined with the aid of boundary conditions, a...

  14. AIR: fused Analytical and Iterative Reconstruction method for computed tomography

    CERN Document Server

    Yang, Liu; Qi, Sharon X; Gao, Hao

    2013-01-01

    Purpose: CT image reconstruction techniques have two major categories: analytical reconstruction (AR) method and iterative reconstruction (IR) method. AR reconstructs images through analytical formulas, such as filtered backprojection (FBP) in 2D and Feldkamp-Davis-Kress (FDK) method in 3D, which can be either mathematically exact or approximate. On the other hand, IR is often based on the discrete forward model of X-ray transform and formulated as a minimization problem with some appropriate image regularization method, so that the reconstructed image corresponds to the minimizer of the optimization problem. This work is to investigate the fused analytical and iterative reconstruction (AIR) method. Methods: Based on IR with L1-type image regularization, AIR is formulated with a AR-specific preconditioner in the data fidelity term, which results in the minimal change of the solution algorithm that replaces the adjoint X-ray transform by the filtered X-ray transform. As a proof-of-concept 2D example of AIR, FB...

  15. Recent progress of analytical methods of spent nuclear fuel (Review)

    International Nuclear Information System (INIS)

    Analytical methods for the spent nuclear fuel (SF) have been greatly innovated recently. This methodological innovation is mainly caused by rapid and remarkable progress of induced coupled plasma-mass spectrometry (ICP-MS) which is utilized for the isotopic analysis of actinoid elements (U, Np, Pu, Am, Cm) and fission product elements in the SF samples. The quantity of the objective element as well as the volume of the sample solution needed for the ICP-MS measurement are, in principle, much less than required for the measurement by other analytical methods. Because of its highly sensitive characteristic, the ICP-MS becomes the most powerful method for the analysis of radioactive samples such as SF. The utilization of the analytical method based on the ICP-MS makes it possible to reduce the radiation dose of the operator and to minimize the amount of the radioactive wastes generated from the analytical work. For the precise and accurate isotopic analysis of the objective element in the SF sample by mass spectrometry, the interfering element having isobars needs to be separated prior to the measurement. The separation method has also made remarkable progress in recent years. Most of the advancement of the separation method involves the improvement of the conventional method such as ion-chromatography, high performance liquid chromatography or extraction chromatography so that the separation method conforms to the detection using advanced ICP-MS. Furthermore, the application of such new method as the capillary electrophoresis chromatography to the separation of the element in the SF is examined. Ultimately, the analytical system with the chromatographic separation process combined on-line with the ICP-MS detection is considered to be the most suitable and has been developed and employed to the sensitive, precise and rapid analysis of the many isotopes of various elements in the SF. In Institute of Transuranium (EU) and Argonne National Laboratory (USA), the analyses

  16. Hanford environmental analytical methods (methods as of March 1990)

    International Nuclear Information System (INIS)

    Information is provided on the techniques employed towards the chemical analysis of volatile, semi-volatile matter, pesticides and PCB's at the Hanford Reservation. Sample preparation methods are included

  17. A simple analytical method for deflation prediction of inflatable structures

    Institute of Scientific and Technical Information of China (English)

    李庆松; 卿强; 龚景海

    2015-01-01

    The static performance of inflatable structures has been well studied and the dynamic deployment simulation has received much attention. However, very few studies focus on its deflation behavior. Although there are several dynamic finite element algorithms that can be applied to the deflation simulation, their computation costs are expensive, especially for large scale structures. In this work, a simple method based on classic thermodynamics and the analytical relationship between air and membrane was proposed to efficiently analyze the air state variables under the condition of ventilation. Combined with failure analysis of static bearing capacity, a fast incremental analytical method was presented to predict both elastic and post wrinkling deflation process of inflatable structures. Comparisons between simplified analysis, dynamic finite element simulation, and a full-scale experimental test are presented and the suitability of this simple method for solving the air state and predicting the deflation behavior of inflatable structures is proved.

  18. Developments and retrospectives in Lie theory geometric and analytic methods

    CERN Document Server

    Penkov, Ivan; Wolf, Joseph

    2014-01-01

    This volume reviews and updates a prominent series of workshops in representation/Lie theory, and reflects the widespread influence of those  workshops in such areas as harmonic analysis, representation theory, differential geometry, algebraic geometry, and mathematical physics.  Many of the contributors have had leading roles in both the classical and modern developments of Lie theory and its applications. This Work, entitled Developments and Retrospectives in Lie Theory, and comprising 26 articles, is organized in two volumes: Algebraic Methods and Geometric and Analytic Methods. This is the Geometric and Analytic Methods volume. The Lie Theory Workshop series, founded by Joe Wolf and Ivan Penkov and joined shortly thereafter by Geoff Mason, has been running for over two decades. Travel to the workshops has usually been supported by the NSF, and local universities have provided hospitality. The workshop talks have been seminal in describing new perspectives in the field covering broad areas of current re...

  19. FORECASTING PILE SETTLEMENT ON CLAYSTONE USING NUMERICAL AND ANALYTICAL METHODS

    Directory of Open Access Journals (Sweden)

    Ponomarev Andrey Budimirovich

    2016-06-01

    Full Text Available In the article the problem of designing pile foundations on claystones is reviewed. The purpose of this paper is comparative analysis of the analytical and numerical methods for forecasting the settlement of piles on claystones. The following tasks were solved during the study: 1 The existing researches of pile settlement are analyzed; 2 The characteristics of experimental studies and the parameters for numerical modeling are presented, methods of field research of single piles’ operation are described; 3 Calculation of single pile settlement is performed using numerical methods in the software package Plaxis 2D and analytical method according to the requirements SP 24.13330.2011; 4 Experimental data is compared with the results of analytical and numerical calculations; 5 Basing on these results recommendations for forecasting pile settlement on claystone are presented. Much attention is paid to the calculation of pile settlement considering the impacted areas in ground space beside pile and the comparison with the results of field experiments. Basing on the obtained results, for the prediction of settlement of single pile on claystone the authors recommend using the analytical method considered in SP 24.13330.2011 with account for the impacted areas in ground space beside driven pile. In the case of forecasting the settlement of single pile on claystone by numerical methods in Plaxis 2D the authors recommend using the Hardening Soil model considering the impacted areas in ground space beside the driven pile. The analyses of the results and calculations are presented for examination and verification; therefore it is necessary to continue the research work of deep foundation at another experimental sites to improve the reliability of the calculation of pile foundation settlement. The work is of great interest for geotechnical engineers engaged in research, design and construction of pile foundations.

  20. Substantive provisions of Numeral-analytical boundary elements method

    Directory of Open Access Journals (Sweden)

    V.F. Orobey

    2011-06-01

    Full Text Available Substantive propositions of the new method of design calculation, that got the name "Numeral-analytical of boundary elements method", offered by authors, are brought. A method consists of development of the fundamental system of decisions (analytically and Green functions (also analytically for every examined task.For the account of certain border terms, or terms of contact between the separate modules (the separate element of the system is so named the small system of linear algebraic equalizations, that must be decided numeral, is made.Discretisation only of border of the area occupied by an object, sharply diminishes the order of the system of resolvent equalizations; there is possibility of decline of regularity of the decided task. A method is strictly reasonable mathematically, as uses the fundamental decisions of differential equalizations, and, means, within the framework of the accepted hypotheses allows to get the exact meaning of parameters of task (efforts, moving, tensions, currents, frequencies of eigentones, critical forces of loss of stability et cetera into an area.Simplicity of logic of algorithm, good convergence of decision, high stability and small accumulation of errors at numeral operations, are marked also.

  1. Analytical methods to calculate correlation functions in quantum statistical physics

    International Nuclear Information System (INIS)

    In the work there is presented a brief but clear and quite reserved account of two analytical methods to calculate correlation functions in quantum statistical physics, proceeding from the first principles, i.e., the most broadly used at present two-time temperature Green's functions method and a new, so-called 'direct algebraic' method (DAM). The aim of this work is to show on the concrete examples of live the most broadly used models of quantum statistical physics, mathematical and technical clarity and simplicity of DAM and hence its practical value

  2. Scoping analytical usability evaluation methods: A case study

    OpenAIRE

    Blandford, A. E.; Hyde, J K; Green, T. R. G.; Connell, I.

    2008-01-01

    Analytical usability evaluation methods (UEMs) can complement empirical evaluation of systems: for example, they can often be used earlier in design and can provide accounts of why users might experience difficulties, as well as what those difficulties are. However, their properties and value are only partially understood. One way to improve our understanding is by detailed comparisons using a single interface or system as a target for evaluation, but we need to look deeper than simple proble...

  3. 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

  4. Analytical Method Development & Validation for Related Substances Method of Busulfan Injection by Ion Chromatography Method

    Directory of Open Access Journals (Sweden)

    Rewaria S

    2013-05-01

    Full Text Available A new simple, accurate, precise and reproducible Ion chromatography method has been developed forthe estimation of Methane sulfonic acid in Busulfan injectable dosage. The method which is developedis also validated in complete compliance with the current regulatory guidelines by using well developedanalytical method validation techniques and tools which comprises with the analytical method validationparameters like Linearity, LOD and LOQ determination, Accuracy, Method precision, Specificity,System suitability, Robustness, Ruggedness etc. by adopting the current method the linearity obtained isnear to 0.999 and thus this shows that the method is capable to give a good detector response, therecovery calculated was within the range of 85% to 115% of the specification limits.

  5. Analytical methods to identify irradiated food--a review

    International Nuclear Information System (INIS)

    The ability to analytically identify irradiated food - complementary to certification - helps to enhance consumers confidence. It makes it possible to check compliance with existing regulations (e.g. enforcement of labelling, control of prohibition) and to facilitate international food trade. An enormous effort--both at the world-wide international level (ADMIT) and at European (BCR)/national level--has led to several validated and even standardized (CEN) detection methods for a large number of different food products. In this short review, the present methods are summarized, limitations and new developments drafted

  6. SRXRF Experiments and Analytical Methods of Mineral Individual Fluid Inclusions

    Institute of Scientific and Technical Information of China (English)

    Wu Chunxue; Huang Yuying; Li Hongkui; Chen Chuanren; He Wei; Li Kuifa

    2007-01-01

    This paper focuses on the micro-beam and trace element non-destructive experiment and analytical method of mineral fluid inclusions by synchrotron radiation X-ray fluorescence (SRXRF) microprobe at Beijing Synchrotron Radiation Facility (BSRF). The experimental instrument, measurement process and calculating method are introduced. A set of oil- and gas-containing typical mineral fluid inclusions taken from the Tazhong and Lunnan oilfields in the Tarim Basin were analyzed non-destructively. The trace element contents in the fluid inclusions may provide guidance for oil and gas exploration and development.

  7. Organic analysis and analytical methods development: FY 1995 progress report

    Energy Technology Data Exchange (ETDEWEB)

    Clauss, S.A.; Hoopes, V.; Rau, J. [and others

    1995-09-01

    This report describes the status of organic analyses and developing analytical methods to account for the organic components in Hanford waste tanks, with particular emphasis on tanks assigned to the Flammable Gas Watch List. The methods that have been developed are illustrated by their application to samples obtained from Tank 241-SY-103 (Tank 103-SY). The analytical data are to serve as an example of the status of methods development and application. Samples of the convective and nonconvective layers from Tank 103-SY were analyzed for total organic carbon (TOC). The TOC value obtained for the nonconvective layer using the hot persulfate method was 10,500 {mu}g C/g. The TOC value obtained from samples of Tank 101-SY was 11,000 {mu}g C/g. The average value for the TOC of the convective layer was 6400 {mu}g C/g. Chelator and chelator fragments in Tank 103-SY samples were identified using derivatization. gas chromatography/mass spectrometry (GC/MS). Organic components were quantified using GC/flame ionization detection. Major components in both the convective and nonconvective-layer samples include ethylenediaminetetraacetic acid (EDTA), nitrilotriacetic acid (NTA), succinic acid, nitrosoiminodiacetic acid (NIDA), citric acid, and ethylenediaminetriacetic acid (ED3A). Preliminary results also indicate the presence of C16 and C18 carboxylic acids in the nonconvective-layer sample. Oxalic acid was one of the major components in the nonconvective layer as determined by derivatization GC/flame ionization detection.

  8. Gaussian Analytic Centroiding method of star image of star tracker

    Science.gov (United States)

    Wang, Haiyong; Xu, Ershuai; Li, Zhifeng; Li, Jingjin; Qin, Tianmu

    2015-11-01

    The energy distribution of an actual star image coincides with the Gaussian law statistically in most cases, so the optimized processing algorithm about star image centroiding should be constructed also by following Gaussian law. For a star image spot covering a certain number of pixels, the marginal distribution of the gray accumulation on rows and columns are shown and analyzed, based on which the formulas of Gaussian Analytic Centroiding method (GAC) are deduced, and the robustness is also promoted due to the inherited filtering effect of gray accumulation. Ideal reference star images are simulated by the PSF (point spread function) with integral form. Precision and speed tests for the Gaussian Analytic formulas are conducted under three scenarios of Gaussian radius (0.5, 0.671, 0.8 pixel), The simulation results show that the precision of GAC method is better than that of the other given algorithms when the Gaussian radius is not bigger than 5 × 5 pixel window, a widely used parameter. Above all, the algorithm which consumes the least time is still the novel GAC method. GAC method helps to promote the comprehensive performance in the attitude determination of a star tracker.

  9. An Approximate Analytical Method of the Nonlinear Vibroacoustic Coupling System

    Directory of Open Access Journals (Sweden)

    Qizheng Zhou

    2014-01-01

    Full Text Available An approximate analytical method of the nonlinear vibroacoustic coupling system is proposed for the first time. Taking the Duffing oscillator-plate-medium system as an example, the nonlinear vibroacoustic coupling equations are developed using variational principle. The two major difficulties which lie in solving the coupling equations are the uncertain motion of the oscillator and the surface acoustic pressure on the plate, a system for which the fluid-structure coupling cannot be neglected. Based on the incremental harmonic balance (IHB method, the motion of the oscillator is expressed in the form of the Fourier series, and then the modal expression method and the incoherent assumption are employed to discretize the displacement and the surface pressure of the plate. Then the approximate analytical solution is given by the IHB method. The characteristics of acoustic radiation and surface quadratic velocity of the plate, the nonlinear characteristics of oscillator, and the influence of the excitation frequency and the nonlinear stiffness on the results are investigated by the numerical simulation. The results show that the excitation at the frequency close to the natural frequency of the oscillator can produce a significant response of the third-harmonic generation which determines the vibroacoustic characteristics of the plate.

  10. A nonlinear analytic function expansion nodal method for transient calculations

    Energy Technology Data Exchange (ETDEWEB)

    Joo, Han Gyn; Park, Sang Yoon; Cho, Byung Oh; Zee, Sung Quun [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1998-12-31

    The nonlinear analytic function expansion nodal (AFEN) method is applied to the solution of the time-dependent neutron diffusion equation. Since the AFEN method requires both the particular solution and the homogeneous solution to the transient fixed source problem, the derivation of the solution method is focused on finding the particular solution efficiently. To avoid complicated particular solutions, the source distribution is approximated by quadratic polynomials and the transient source is constructed such that the error due to the quadratic approximation is minimized, In addition, this paper presents a new two-node solution scheme that is derived by imposing the constraint of current continuity at the interface corner points. The method is verified through a series of application to the NEACRP PWR rod ejection benchmark problems. 6 refs., 2 figs., 1 tab. (Author)

  11. Analytical methods for toxic gases from thermal degradation of polymers

    Science.gov (United States)

    Hsu, M.-T. S.

    1977-01-01

    Toxic gases evolved from the thermal oxidative degradation of synthetic or natural polymers in small laboratory chambers or in large scale fire tests are measured by several different analytical methods. Gas detector tubes are used for fast on-site detection of suspect toxic gases. The infrared spectroscopic method is an excellent qualitative and quantitative analysis for some toxic gases. Permanent gases such as carbon monoxide, carbon dioxide, methane and ethylene, can be quantitatively determined by gas chromatography. Highly toxic and corrosive gases such as nitrogen oxides, hydrogen cyanide, hydrogen fluoride, hydrogen chloride and sulfur dioxide should be passed into a scrubbing solution for subsequent analysis by either specific ion electrodes or spectrophotometric methods. Low-concentration toxic organic vapors can be concentrated in a cold trap and then analyzed by gas chromatography and mass spectrometry. The limitations of different methods are discussed.

  12. Evolution of microbiological analytical methods for dairy industry needs

    Directory of Open Access Journals (Sweden)

    Daniele eSohier

    2014-02-01

    Full Text Available Traditionally, culture-based methods have been used to enumerate microbial populations in dairy products. Recent developments in molecular methods now enable faster and more sensitive analyses than classical microbiology procedures. These molecular tools allow a detailed characterization of cell physiological states and bacterial fitness and thus, offer new perspectives to integration of microbial physiology monitoring to improve industrial processes. This review summarizes the methods described to enumerate and characterize physiological states of technological microbiota in dairy products, and discusses the current deficiencies in relation to the industry’s needs. Recent studies show that PCR-based methods can successfully be applied to quantify fermenting microbes and probiotics in dairy products. Flow cytometry and omics technologies also show interesting analytical potentialities. However, they still suffer from a lack of validation and standardization for quality control analyses, as reflected by the absence of performance studies and official international standards.

  13. Implementation of the Maximum Entropy Method for Analytic Continuation

    CERN Document Server

    Levy, Ryan; Gull, Emanuel

    2016-01-01

    We present $\\texttt{Maxent}$, a tool for performing analytic continuation of spectral functions using the maximum entropy method. The code operates on discrete imaginary axis datasets (values with uncertainties) and transforms this input to the real axis. The code works for imaginary time and Matsubara frequency data and implements the 'Legendre' representation of finite temperature Green's functions. It implements a variety of kernels, default models, and grids for continuing bosonic, fermionic, anomalous, and other data. Our implementation is licensed under GPLv2 and extensively documented. This paper shows the use of the programs in detail.

  14. Performance of analytical methods for tomographic gamma scanning

    International Nuclear Information System (INIS)

    The use of gamma-ray computerized tomography for nondestructive assay of radioactive materials has led to the development of specialized analytical methods. Over the past few years, Los Alamos has developed and implemented a computer code, called ARC-TGS, for the analysis of data obtained by tomographic gamma scanning (TGS). ARC-TGS reduces TGS transmission and emission tomographic data, providing the user with images of the sample contents, the activity or mass of selected radionuclides, and an estimate of the uncertainty in the measured quantities. The results provided by ARC-TGS can be corrected for self-attenuation when the isotope of interest emits more than one gamma-ray. In addition, ARC-TGS provides information needed to estimate TGS quantification limits and to estimate the scan time needed to screen for small amounts of radioactivity. In this report, an overview of the analytical methods used by ARC-TGS is presented along with an assessment of the performance of these methods for TGS

  15. Analytical methods used by the geochemical section: water

    International Nuclear Information System (INIS)

    The authors describe the analytical methods used by the C.E.A. Geochemical Section to determine the chemical composition of natural waters encountered during the prospecting of uraniferous deposits or in the course of mining operations. Because of the diversity of the samples and the different items of information requested, methods were selected and adapted to answer to the demands peculiar to mining research. Methods and know-how concerning the quantitative analysis of natural water to find out the concentration of the following chemicals are reviewed: carbonates and bicarbonates, calcium, magnesium, chlorides, sodium and potassium, sulfates, nitrates, silica, phosphates, iron, manganese, aluminium, fluorides, dissolved oxygen, CO2, SH2 and sulphur, and uranium. (authors)

  16. Analytical method of spectra calculations in the Bargmann representation

    International Nuclear Information System (INIS)

    We formulate a universal method for solving an arbitrary quantum system which, in the Bargmann representation, is described by a system of linear equations with one independent variable, such as one- and multi-photon Rabi models, or N level systems interacting with a single mode of the electromagnetic field and their various generalizations. We explain three types of conditions that determine the spectrum and show their usage for two deformations of the Rabi model. We prove that the spectra of both models are just zeros of transcendental functions, which in one case are given explicitly in terms of confluent Heun functions. - Highlights: • Analytical method of spectrum determination in Bargmann representation is proposed. • Three types of conditions determining spectrum are identified. • Method to two generalizations of the Rabi system is applied

  17. Using analytic network process for evaluating mobile text entry methods.

    Science.gov (United States)

    Ocampo, Lanndon A; Seva, Rosemary R

    2016-01-01

    This paper highlights a preference evaluation methodology for text entry methods in a touch keyboard smartphone using analytic network process (ANP). Evaluation of text entry methods in literature mainly considers speed and accuracy. This study presents an alternative means for selecting text entry method that considers user preference. A case study was carried out with a group of experts who were asked to develop a selection decision model of five text entry methods. The decision problem is flexible enough to reflect interdependencies of decision elements that are necessary in describing real-life conditions. Results showed that QWERTY method is more preferred than other text entry methods while arrangement of keys is the most preferred criterion in characterizing a sound method. Sensitivity analysis using simulation of normally distributed random numbers under fairly large perturbation reported the foregoing results reliable enough to reflect robust judgment. The main contribution of this paper is the introduction of a multi-criteria decision approach in the preference evaluation of text entry methods. PMID:26360215

  18. The evolution of analytical chemistry methods in foodomics.

    Science.gov (United States)

    Gallo, Monica; Ferranti, Pasquale

    2016-01-01

    The methodologies of food analysis have greatly evolved over the past 100 years, from basic assays based on solution chemistry to those relying on the modern instrumental platforms. Today, the development and optimization of integrated analytical approaches based on different techniques to study at molecular level the chemical composition of a food may allow to define a 'food fingerprint', valuable to assess nutritional value, safety and quality, authenticity and security of foods. This comprehensive strategy, defined foodomics, includes emerging work areas such as food chemistry, phytochemistry, advanced analytical techniques, biosensors and bioinformatics. Integrated approaches can help to elucidate some critical issues in food analysis, but also to face the new challenges of a globalized world: security, sustainability and food productions in response to environmental world-wide changes. They include the development of powerful analytical methods to ensure the origin and quality of food, as well as the discovery of biomarkers to identify potential food safety problems. In the area of nutrition, the future challenge is to identify, through specific biomarkers, individual peculiarities that allow early diagnosis and then a personalized prognosis and diet for patients with food-related disorders. Far from the aim of an exhaustive review of the abundant literature dedicated to the applications of omic sciences in food analysis, we will explore how classical approaches, such as those used in chemistry and biochemistry, have evolved to intersect with the new omics technologies to produce a progress in our understanding of the complexity of foods. Perhaps most importantly, a key objective of the review will be to explore the development of simple and robust methods for a fully applied use of omics data in food science. PMID:26363946

  19. Reactor analysis methods. 1. Removal of Numerical Singularity in Analytical Nodal Methods via Continued Factoring

    International Nuclear Information System (INIS)

    In the modern nodal methods of the analytic function expansion nodal method (AFEN) and the analytic nodal method (ANM), analytic functions are used to describe the flux distribution in a node. AFEN uses analytic solutions of the diffusion equation in multidimensional geometry without transverse integration, while ANM uses analytic solutions of the one-dimensional equations resulting from transverse integration with quadratic leakage approximation. The analytic functions used in these methods are explicit functions of keff of the core. There was some concern about the numerical stability in these methods, when the core contains nearly no-net-leakage nodes; i.e., k∞ of a node approaches keff of the core. Reference 5 discusses this instability problem in the two-node ANM nonlinear solution and describes an approximate method that is equivalent to a Taylor series expansion of the analytic solution, truncated in the first order. The present paper provides an exact method that avoids this problem without any approximation. This numerical singularity removal method decomposes the highly ill conditioned system into singular and nonsingular parts and cancels out the singular part. The method is applied to the formulation of AFEN, and tests are performed in both rectangular and hexagonal geometries. The singularity removal method was implemented in AFEN to solve no-net-leakage node embedded problems in both rectangular and hexagonal geometries. To test the method in rectangular geometry, the fast and thermal fission cross sections of a fuel assembly in the EPRI-9R core were modified such that a small eigenvalue of Λ=-3.56146x10-8 is generated. AFEN solves the problem accurately in the presence of a highly singular node. In hexagonal geometry, the VVER- 440 core was tested with an eigenvalue of -1.14308 x 10-8, and similarly accurate results were obtained. In the analytical nodal methods such as AFEN and ANM, the numerical instability problem may occur in the presence of

  20. The use of graphic-analytical method in investment design

    Directory of Open Access Journals (Sweden)

    Musatova Tatiana

    2016-04-01

    Full Text Available We investigate the possibility of using the network planning method for the goals and objectives of the investment project. The author suggests a network model of implementing the investment project related to the manufacture of aluminum structures. Insufficient study of adaptation of methodological issues of organization of technological processes to the investment project of socio-economic activities has led to the relevance and identified the purpose of the present study. The presented network model allows project participants to optimize the time and costs of various types of project resources. It includes the calculation of the parameters of the network schedule and the actual model of interrelated events and activities. Scientific and practical significance of the results of research is related to the possibility of practical application of graphic-analytical method for the preparation of technical and economic documentation for the investment project.

  1. Friedmann--Lemaitre Cosmologies via Roulettes and Other Analytic Methods

    CERN Document Server

    Chen, Shouxin; Yang, Yisong

    2015-01-01

    In this work a series of methods are developed for understanding the Friedmann equation when it is beyond the reach of the Chebyshev theorem. First it will be demonstrated that every solution of the Friedmann equation admits a representation as a roulette such that information on the latter may be used to obtain that for the former. Next the Friedmann equation is integrated for a quadratic equation of state and for the Randall--Sundrum II universe, leading to a harvest of a rich collection of new interesting phenomena. Finally an analytic method is used to isolate the asymptotic behavior of the solutions of the Friedmann equation, when the equation of state is of an extended form which renders the integration impossible, and to establish a universal exponential growth law.

  2. Potentialities and possible applications of a new analytical method (PIXE)

    International Nuclear Information System (INIS)

    In 1970, a new method was introduced for trace analysis, namely, the X-ray emission induced by charged particles (PIXE). It has been shown that when protons in the few MeV range are used for the excitation of inner shell electrons and solid state detectors for the detection of the characteristic X-rays, we dispose of a powerful multi-elemental analytical tool of high sensitivity. In contrast to activation spectrometry, this is an in beam technique, irradiation and measuring being performed at the same time. The foundations of the method are described experimental arrangements and problems related to beam transport, target preparation an spectrum analysis. A detailed discussion on precision, accuracy and sensitivity is presented. Applications in biology, medicine, environmental and materials sciences are discussed. (Author)

  3. Introduction to Analytical Methods for Internal Combustion Engine Cam Mechanisms

    CERN Document Server

    Williams, J J

    2013-01-01

    Modern design methods of Automotive Cam Design require the computation of a range of parameters. This book provides a logical sequence of steps for the derivation of the relevant equations from first principles, for the more widely used cam mechanisms. Although originally derived for use in high performance engines, this work is equally applicable to the design of mass produced automotive and other internal combustion engines.   Introduction to Analytical Methods for Internal Combustion Engine Cam Mechanisms provides the equations necessary for the design of cam lift curves with an associated smooth acceleration curve. The equations are derived for the kinematics and kinetics of all the mechanisms considered, together with those for cam curvature and oil entrainment velocity. This permits the cam shape, all loads, and contact stresses to be evaluated, and the relevant tribology to be assessed. The effects of asymmetry on the manufacture of cams for finger follower and offset translating curved followers is ...

  4. A novel unified coding analytical method for Internet of Things

    Science.gov (United States)

    Sun, Hong; Zhang, JianHong

    2013-08-01

    This paper presents a novel unified coding analytical method for Internet of Things, which abstracts out the `displacement goods' and `physical objects', and expounds the relationship thereof. It details the item coding principles, establishes a one-to-one relationship between three-dimensional spatial coordinates of points and global manufacturers, can infinitely expand, solves the problem of unified coding in production phase and circulation phase with a novel unified coding method, and further explains how to update the item information corresponding to the coding in stages of sale and use, so as to meet the requirement that the Internet of Things can carry out real-time monitoring and intelligentized management to each item.

  5. A general multigroup formulation of the analytic nodal method

    International Nuclear Information System (INIS)

    In this paper the theoretical description of an alternative approach to the Analytic Nodal Method is given, in which a full multigroup formulations is developed. This approach differs from the well known QUANDRY approach in three aspects. Firstly, a notation which is more widely used in Quantum Mechanics has been adopted to enable a clear and concise presentation of this multigroup approach. A basis transformation is then used to reduce the directional equations to a scalar form and finally, Green's secondary identity is used to rewrite each of the resulting scalar equations in a form which eventually leads to a response matrix, as opposed to using classical methods to actually solve the coupled multigroup directional equations

  6. A Review on Supercritical Fluid Extraction as New Analytical Method

    Directory of Open Access Journals (Sweden)

    K. A. Abbas

    2008-01-01

    Full Text Available This review study summarized the Supercritical Fluid Extraction (SFE as new analytical method. The advantage and disadvantage of CO2 (SC-CO2 as well as special applications of SFE in food processing such as removal of fat from food, enrichment of vitamin E from natural sources, removal of alcohol from wine and beer, encapsulation of liquids for engineering solid products and extraction and characterization of functional compounds were also highlighted. The study also covered the application of SFE in food safety such as rapid analysis for fat content, rapid analysis for pesticides in foods as well as the recent applications of SFE in food such as supercritical particle formation and nan particle formation and ssupercritical drying. The outcome finding confirmed that SFE was found to be advance, fast, reliable, clean and cheap methods for routine food analysis.

  7. GenoSets: visual analytic methods for comparative genomics.

    Directory of Open Access Journals (Sweden)

    Aurora A Cain

    Full Text Available Many important questions in biology are, fundamentally, comparative, and this extends to our analysis of a growing number of sequenced genomes. Existing genomic analysis tools are often organized around literal views of genomes as linear strings. Even when information is highly condensed, these views grow cumbersome as larger numbers of genomes are added. Data aggregation and summarization methods from the field of visual analytics can provide abstracted comparative views, suitable for sifting large multi-genome datasets to identify critical similarities and differences. We introduce a software system for visual analysis of comparative genomics data. The system automates the process of data integration, and provides the analysis platform to identify and explore features of interest within these large datasets. GenoSets borrows techniques from business intelligence and visual analytics to provide a rich interface of interactive visualizations supported by a multi-dimensional data warehouse. In GenoSets, visual analytic approaches are used to enable querying based on orthology, functional assignment, and taxonomic or user-defined groupings of genomes. GenoSets links this information together with coordinated, interactive visualizations for both detailed and high-level categorical analysis of summarized data. GenoSets has been designed to simplify the exploration of multiple genome datasets and to facilitate reasoning about genomic comparisons. Case examples are included showing the use of this system in the analysis of 12 Brucella genomes. GenoSets software and the case study dataset are freely available at http://genosets.uncc.edu. We demonstrate that the integration of genomic data using a coordinated multiple view approach can simplify the exploration of large comparative genomic data sets, and facilitate reasoning about comparisons and features of interest.

  8. Algebraic and analytic reconstruction methods for dynamic tomography.

    OpenAIRE

    Desbat, Laurent; Rit, S; Clackdoyle, R.; Mennessier, C; Promayon, Emmanuel; Ntalampeki, S.

    2007-01-01

    In this work, we discuss algebraic and analytic approaches for dynamic tomography. We present a framework of dynamic tomography for both algebraic and analytic approaches. We finally present numerical experiments.

  9. Algebraic and analytic reconstruction methods for dynamic tomography.

    Science.gov (United States)

    Desbat, L; Rit, S; Clackdoyle, R; Mennessier, C; Promayon, E; Ntalampeki, S

    2007-01-01

    In this work, we discuss algebraic and analytic approaches for dynamic tomography. We present a framework of dynamic tomography for both algebraic and analytic approaches. We finally present numerical experiments. PMID:18002059

  10. Analytical methods and problems for the diamides type of extractants

    International Nuclear Information System (INIS)

    Diamides of carboxylic acids and especially malonamides are able to extract alpha emitters (including trivalent ions such as Am and Cm) contained in the wastes solutions of the nuclear industry. As they are completely incinerable and easy to purify, they could be an alternative to the mixture CMPO-TBP which is used in the TRUEX process. A large oxyalkyl radical enhances the distribution coefficients of americium in nitric acid sufficiently to permit the decontamination of wastes solutions in a classical mixers-settlers battery. Now researches are pursued with the aim of optimizing the formula of extractant, the influence of the structure of the extractant on its basicity and stability under radiolysis and hydrolysis is investigated. Analytical methods (potentiometry and NMR of C13) have been developed for solvent titration and to evaluate the percentage of degradation and to identify some of the degradation products

  11. Laser induced uranium fluorescence as an analytical method

    International Nuclear Information System (INIS)

    A laser induced fluorescence system was developed to measure uranium trace level amounts in aqueous solution with reliable and simple materials and electronics. A nitrogen pulsed laser was built with the storage energy capacitor directly coupled to laser tube electrodes as a transmission line device. This laser operated at 3Hz repetition rate with peak intensity around 21 Kw and temporal width of 4.5 x 10-9 s. A sample compartment made of rigid PVC and a photomultiplier housing of aluminium were constructed and assembled forming a single integrated device. As a result of this prototype system we made several analytical measurements with U dissolved in nitric acid to obtain a calibration curve. We obtained a straight line from a plot of U concentration versus fluorescence intensity fitted by a least square method that produced a regression coefficient of 0.994. The lower limit of U determination was 30 ppb -+ 3.5%. (Author)

  12. Nuclear analytical methods for trace element studies in calcified tissues

    International Nuclear Information System (INIS)

    Full text: Various nuclear analytical methods have been developed and applied to determine the elemental composition of calcified tissues (teeth and bones). Fluorine was determined by prompt gamma activation analysis through the 19F(p,ag)16O reaction. Carbon was measured by activation analysis with He-3 ions, and the technique of Proton-Induced X-ray Emission (PIXE) was applied to simultaneously determine Ca, P, and trace elements in well-documented teeth. Dental hard tissues, enamel, dentine, cement, and their junctions, as well as different parts of the same tissue, were examined separately. Furthermore, using a Proton Microprobe, we measured the surface distribution of F and other elements on and around carious lesions on the enamel. The depth profiles of F, and other elements, were also measured right up to the amelodentin junction

  13. Modelling of packet traffic with matrix analytic methods

    DEFF Research Database (Denmark)

    Andersen, Allan T.

    1995-01-01

    The dissertation is concerned with modelling various performance aspects pertaining to packet switched telecommunication networks. The emphsis has been put on versatile modelling of the packet arrival process which is a very relevant issue in cotext with the future Broadband Integrated Service Data...... network services i.e. 800 and 900 calls and advanced mobile communication services. The Markovian Arrival Process (MAP) has been used as a versatile tool to model the packet arrival process. Applying the MAP facilitates the use of Matrix Analytic methods to obtain performance measures associated with for...... example the single server queue with a MAP arrival process and a general service time distribution. Measured SS7 traffic data has been analyzed as a part of this study. Recently there has been expressed concern regarding adverse behaviour of measured SS7 traffic i.e. long range dependence. Our studies did...

  14. An Analytical Method of Auxiliary Sources Solution for Plane Wave Scattering by Impedance Cylinders

    DEFF Research Database (Denmark)

    Larsen, Niels Vesterdal; Breinbjerg, Olav

    Analytical Method of Auxiliary Sources solutions for plane wave scattering by circular impedance cylinders are derived by transformation of the exact eigenfunction series solutions employing the Hankel function wave transformation. The analytical Method of Auxiliary Sources solution thus obtained...

  15. CT hepatic perfusion measurement: Comparison of three analytic methods

    International Nuclear Information System (INIS)

    Objectives: To compare the efficacy of three analytic methods, maximum slope (MS), dual-input single-compartment model (CM) and deconvolution (DC), for CT measurements of hepatic perfusion and assess the effects of extra-hepatic systemic factors. Materials and methods: Eighty-eight patients who were suspected of having metastatic liver tumors underwent hepatic CT perfusion. The scans were performed at the hepatic hilum 7–77 s after administration of contrast material. Hepatic arterial and portal perfusions (HAP and HPP, ml/min/100 ml) and arterial perfusion fraction (APF, %) were calculated with the three methods, followed by correlation assessment. Partial correlation analysis was used to assess the effects on hepatic perfusion values by various factors such as age, sex, risk of cardiovascular diseases, arrival time of contrast material at abdominal aorta, transit time from abdominal aorta to hepatic parenchyma, and liver dysfunction. Results: Mean HAP of MS was significantly higher than DC. HPP of CM was significantly higher than MS and CM, and HPP of MS was significantly higher than DC. There was no significant difference in APF. HAP and APF showed significant and moderate correlations among the methods. HPP showed significant and moderate correlations between CM and DC, and poor correlation between MS and CM or DC. All methods showed weak correlations between HAP or APF and age or sex. Finally, MS showed weak correlations between HAP or HPP and arrival time or cardiovascular risks. Conclusions: Hepatic perfusion values arrived at with the three methods are not interchangeable. CM and DC are less susceptible to extra-hepatic systemic factors

  16. Analytical methods for (oxidized) plasmalogens: Methodological aspects and applications.

    Science.gov (United States)

    Fuchs, B

    2015-05-01

    Plasmalogens are a unique class of glycerophospholipids (GPLs) containing a fatty alcohol linked by a vinyl-ether moiety at the sn-1 position of the glycerol backbone. There is normally a polyunsaturated fatty acyl residue at the sn-2 position. These two features provide interesting properties to the plasmalogen GPL. Their physiological roles have been challenging to elucidate, although plasmalogens represent up to 20% of the total membrane GPLs in humans. Recent studies have revealed plasmalogen deficiencies associated with several human disorders; therefore, plasmalogens are likely to be specific to different tissues, metabolic processes, and developmental stages. The first chapter of this review will discuss the molecular structure and chemistry of plasmalogens, their biological roles, and their distributions in cells and tissues in different species. In the second chapter, currently used methods of analyzing plasmalogens and their degradation products are described. Although chromatographic methods will be also discussed, special attention will be given to ((31)P) nuclear magnetic resonance spectroscopy and soft ionization mass spectrometry (MS) techniques such as electrospray ionization and matrix-assisted laser desorption and ionization time-of-flight MS. Finally, in the third chapter of this review selected human diseases and disorders, which are presumably characterized by changes in plasmalogen contents and compositions, are described and the analytical methods used are discussed. PMID:25536419

  17. Analytical performance of radiochemical method for americium determination in urine

    International Nuclear Information System (INIS)

    This paper presents an analytical method developed and adapted for separation and analysis of Plutonium (Pu) isotopes and Americium (Am) in urine samples. The proposed method will attend the demand of internal exposure monitoring program for workers involved mainly with dismantling rods and radioactive smoke detectors. In this experimental procedure four steps are involved as preparation of samples, sequential radiochemical separation, preparation of the source for electroplating and quantification by alpha spectrometry. In the first stage of radiochemical separation, plutonium is conventionally isolated employing the anion exchange technique. Americium isolation is achieved sequentially by chromatographic extraction (Tru.spec column) from the load and rinse solutions coming from the anion exchange column. The 243Am tracer is added into the sample as chemical yield monitors and to correct the results improving the precision and accuracy. The mean recovery obtained is 60%, and the detection limit for 24h urine sample is 1.0 mBq L-1 in accordance with the literature. Based in the preliminary results, the method is appropriate to be used in monitoring programme of workers with a potential risk of internal contamination. (author)

  18. Analytical methods associated with the recovery of uranium

    International Nuclear Information System (INIS)

    This report summarizes various approaches made to the analysis of materials arising from the processing of Karoo deposits for uranium. These materials include head and residue samples, aqueous solutions and organic solvents and, finally, the precipitated cakes of the elements recovered, i.e. uranium, molybdenum, and arsenic. Analysis was required for these elements and also vanadium, carbon, sulphur, and carbonate in the head and residue samples. The concentration of uranium, molybdenum, and arsenic, other than in the precipitated cakes, ranges from 1 to 2000μg/g, and that of carbon, sulphur, and carbonate from 0,1 to 5 per cent. The analysis of cakes necessitates the determination of silver, arsenic, iron, copper, calcium, magnesium, manganese, molybdenum, lead, tin, titanium, and vanadium within the range 1 to 1000μg/g, and of sodium and silica within the range 10 to 20 000μg/g. The methods used include combustion methods for carbon, sulphur, and carbonate, and atomic-absorption, X-ray-fluorescence, and emission methods for the other analytes. The accuracy of the analysis is within 10 per cent

  19. Study of analytical methods concerning storage effect of underground dam

    Energy Technology Data Exchange (ETDEWEB)

    Hirama, Kunioki; Kuwahara, Toru; Kushima, Masatoshi (Obayashi Corp., Osaka, (Japan))

    1989-08-10

    Information on water balance concerning a catchment area of an underground dam is necessary for effective survey, design, construction and maintenance of the underground dam. Since the observation data of the underground water for about 5 years at some underground dam was obtained this time, they were used for evaluation of the storage effect of the underground dam by using the following four analytical methods, namely water balance equation, combination of tank model and water balance equation, numerical calculation by finite element method and hybrid model of finite element method and tank model. As a result, in case when permeable layers consist of sand and conglomerate of an alluvial system, it was found that evaluation of the storage at the underground dam and its characteristics was feasible and the following points were important for such evaluation; accumulation of observation data over a certain long period, correct information on hydrogeology, suitable composition of tank model, preparation of reasonable numerical model, and combination of analyses such as hybridization of tank models, etc.. 6 refs., 8 figs., 4 tabs.

  20. 21 CFR 530.40 - Safe levels and availability of analytical methods.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Safe levels and availability of analytical methods... Safe levels and availability of analytical methods. (a) In accordance with § 530.22, the following safe... accordance with § 530.22, the following analytical methods have been accepted by FDA:...

  1. 40 CFR 260.21 - Petitions for equivalent testing or analytical methods.

    Science.gov (United States)

    2010-07-01

    ... analytical methods. 260.21 Section 260.21 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Petitions for equivalent testing or analytical methods. (a) Any person seeking to add a testing or analytical method to part 261, 264, or 265 of this chapter may petition for a regulatory amendment under...

  2. 21 CFR 320.29 - Analytical methods for an in vivo bioavailability or bioequivalence study.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Analytical methods for an in vivo bioavailability... Analytical methods for an in vivo bioavailability or bioequivalence study. (a) The analytical method used in... ingredient or therapeutic moiety, or its active metabolite(s), achieved in the body. (b) When the...

  3. Analytic initialization method for xenon oscillation in power reactor simulation

    International Nuclear Information System (INIS)

    The purpose of simulating nuclear power reactor core transients is to predict variations in core behavior due to changes in operating conditions. In the simulation, the initial condition of the core transient should be consistent with the real core state. Especially, the initial conditions of iodine and xenon distributions, which cannot be measured in the core, have dominant effects on the accuracy of the simulation for the transients related with xenon dynamics. If the transient starts from non-equilibrium xenon condition, the accurate initialization of the non-equilibrium iodine and xenon distributions is essential for the prediction of the core transient behavior. In this study, a simple initialization method of non-equilibrium iodine and xenon distributions for the core transient simulation was developed using axial power difference, which is the only measurable parameter related with the non-equilibrium state of the core. For this purpose, the spatial distribution of two-group one-dimensional neutron diffusion equation combined with xenon dynamics equation was expanded with Fourier sine series. It was found that the nonlinearly combined terms of flux and xenon distributions in the equations were canceled by the orthogonal characteristics of the Fourier series using adequate approximation. Therefore, the dynamics equations for axial difference parameters of power, iodine and xenon can be completely linearized and can be converted into an equation system which can be solved analytically. Because the equation system provides with an analytic relationship between the axial differences of power, iodine and xenon, the non-equilibrium iodine and xenon can be represented as functions of the axial power difference. It implies that the initial condition of the transient starting from a non-equilibrium state can be determined from the initial condition of the axial power difference which is a measurable parameter of the core. Using the analytic solution obtained in this

  4. How to assess the quality of your analytical method?

    Science.gov (United States)

    Topic, Elizabeta; Nikolac, Nora; Panteghini, Mauro; Theodorsson, Elvar; Salvagno, Gian Luca; Miler, Marijana; Simundic, Ana-Maria; Infusino, Ilenia; Nordin, Gunnar; Westgard, Sten

    2015-10-01

    Laboratory medicine is amongst the fastest growing fields in medicine, crucial in diagnosis, support of prevention and in the monitoring of disease for individual patients and for the evaluation of treatment for populations of patients. Therefore, high quality and safety in laboratory testing has a prominent role in high-quality healthcare. Applied knowledge and competencies of professionals in laboratory medicine increases the clinical value of laboratory results by decreasing laboratory errors, increasing appropriate utilization of tests, and increasing cost effectiveness. This collective paper provides insights into how to validate the laboratory assays and assess the quality of methods. It is a synopsis of the lectures at the 15th European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) Continuing Postgraduate Course in Clinical Chemistry and Laboratory Medicine entitled "How to assess the quality of your method?" (Zagreb, Croatia, 24-25 October 2015). The leading topics to be discussed include who, what and when to do in validation/verification of methods, verification of imprecision and bias, verification of reference intervals, verification of qualitative test procedures, verification of blood collection systems, comparability of results among methods and analytical systems, limit of detection, limit of quantification and limit of decision, how to assess the measurement uncertainty, the optimal use of Internal Quality Control and External Quality Assessment data, Six Sigma metrics, performance specifications, as well as biological variation. This article, which continues the annual tradition of collective papers from the EFLM continuing postgraduate courses in clinical chemistry and laboratory medicine, aims to provide further contributions by discussing the quality of laboratory methods and measurements and, at the same time, to offer continuing professional development to the attendees. PMID:26408611

  5. An analytical method for predicting postwildfire peak discharges

    Science.gov (United States)

    Moody, John A.

    2012-01-01

    An analytical method presented here that predicts postwildfire peak discharge was developed from analysis of paired rainfall and runoff measurements collected from selected burned basins. Data were collected from 19 mountainous basins burned by eight wildfires in different hydroclimatic regimes in the western United States (California, Colorado, Nevada, New Mexico, and South Dakota). Most of the data were collected for the year of the wildfire and for 3 to 4 years after the wildfire. These data provide some estimate of the changes with time of postwildfire peak discharges, which are known to be transient but have received little documentation. The only required inputs for the analytical method are the burned area and a quantitative measure of soil burn severity (change in the normalized burn ratio), which is derived from Landsat reflectance data and is available from either the U.S. Department of Agriculture Forest Service or the U.S. Geological Survey. The method predicts the postwildfire peak discharge per unit burned area for the year of a wildfire, the first year after a wildfire, and the second year after a wildfire. It can be used at three levels of information depending on the data available to the user; each subsequent level requires either more data or more processing of the data. Level 1 requires only the burned area. Level 2 requires the burned area and the basin average value of the change in the normalized burn ratio. Level 3 requires the burned area and the calculation of the hydraulic functional connectivity, which is a variable that incorporates the sequence of soil burn severity along hillslope flow paths within the burned basin. Measurements indicate that the unit peak discharge response increases abruptly when the 30-minute maximum rainfall intensity is greater than about 5 millimeters per hour (0.2 inches per hour). This threshold may relate to a change in runoff generation from saturated-excess to infiltration-excess overland flow. The

  6. Analytic-numerical method of determining the freezing front location

    Directory of Open Access Journals (Sweden)

    R. Grzymkowski

    2011-07-01

    Full Text Available Mathematical modeling of thermal processes combined with the reversible phase transitions of type: solid phase – liquid phase leads to formulation of the parabolic boundary problems with the moving boundary. Solution of such defined problem requires, most often, to use sophisticated numerical techniques and far advanced mathematical tools. Excellent illustration of the complexity of considered problems, as well as of the variety of approaches used for finding their solutions, gives the papers [1-4]. In the current paper, the authors present the, especially attractive from the engineer point of view, analytic-numerical method for finding the approximate solution of selected class of problems which can be reduced to the one-phase solidification problem of a plate with the unknown a priori, varying in time boundary of the region in which the solution is sought. Proposed method is based on the known formalism of initial expansion of the sought function describing the temperature field into the power series, some coefficients of which are determined with the aid of boundary conditions, and on the approximation of the function defining the location of freezing front with the broken line, parameters of which are numerically determined.

  7. Modern analytic methods applied to the art and archaeology

    International Nuclear Information System (INIS)

    The interaction of diverse areas as the analytic chemistry, the history of the art and the archaeology has allowed the development of a variety of techniques used in archaeology, in conservation and restoration. These methods have been used to date objects, to determine the origin of the old materials and to reconstruct their use and to identify the degradation processes that affect the integrity of the art works. The objective of this chapter is to offer a general vision on the researches that have been realized in the Instituto Nacional de Investigaciones Nucleares (ININ) in the field of cultural goods. A series of researches carried out in collaboration with national investigators and of the foreigner is described shortly, as well as with the great support of degree students and master in archaeology of the National School of Anthropology and History, since one of the goals that have is to diffuse the knowledge of the existence of these techniques among the young archaeologists, so that they have a wider vision of what they could use in an in mediate future and they can check hypothesis with scientific methods. (Author)

  8. Oxcarbazepine: validation and application of an analytical method

    Directory of Open Access Journals (Sweden)

    Paula Cristina Rezende Enéas

    2010-06-01

    Full Text Available Oxcarbazepine (OXC is an important anticonvulsant and mood stabilizing drug. A pharmacopoeial monograph for OXC is not yet available and therefore the development and validation of a new analytical method for quantification of this drug is essential. In the present study, a UV spectrophotometric method for the determination of OXC was developed. The various parameters, such as linearity, precision, accuracy and specificity, were studied according to International Conference on Harmonization Guidelines. Batches of 150 mg OXC capsules were prepared and analyzed using the validated UV method. The formulations were also evaluated for parameters including drug-excipient compatibility, flowability, uniformity of weight, disintegration time, assay, uniformity of content and the amount of drug dissolved during the first hour.Oxcarbazepina (OXC é um fármaco anticonvulsivante e estabilizante do humor. O desenvolvimento e validação de método analítico para quantificação da OXC são de fundamental importância devido à ausência de monografias farmacopéicas oficiais para esse fármaco. Nesse trabalho, um método espectrofotométrico UV para determinação da OXC foi desenvolvido. O método proposto foi validado seguindo os parâmetros de linearidade, precisão, exatidão e especificidade de acordo com as normas da Conferência Internacional de Harmonização. Cápsulas de OXC 150 mg foram preparadas e analisadas utilizando-se o método analítico validado. As formulações foram avaliadas com relação à compatibilidade fármaco-excipientes, fluidez, determinação de peso, tempo de desintegração, doseamento, uniformidade de conteúdo e quantidade do fármaco dissolvido após 60 minutos.

  9. Nuclear Analytical Methods on Archaeological Glass in Thailand

    International Nuclear Information System (INIS)

    Full text: Due to the complex nature of archaeological objects, their analysis needs to use extremely sensitive, spatially resolved and versatile methods that should be as non invasive as possible and give complementary information at different scales; from the macroscopic to the nanometer scales. In this work, SEM-EDS, PIXE and SRXRF were used to analyze the chemical composition of the archaeological glass bead samples that excavated from various historical sites in Thailand. There were number of differences in shade between the glass beads of different colors. The results revealed different in glass types; soda- and potash-, mixed-alkali-, and lead-based glasses. It was noticed that it has been difficult to interpret because of a long period covering and weathering effects. This study may be led to the historical link of the long distance trade and exchange networks in maritime between South-East Asia, South Asia, East Asia and Asia Minor. These analytical measurements in combination are proved useful to investigate the glassy materials and to answer questions posted by archaeologists

  10. Analytical method to estimate resin cement diffusion into dentin

    Science.gov (United States)

    de Oliveira Ferraz, Larissa Cristina; Ubaldini, Adriana Lemos Mori; de Oliveira, Bruna Medeiros Bertol; Neto, Antonio Medina; Sato, Fracielle; Baesso, Mauro Luciano; Pascotto, Renata Corrêa

    2016-05-01

    This study analyzed the diffusion of two resin luting agents (resin cements) into dentin, with the aim of presenting an analytical method for estimating the thickness of the diffusion zone. Class V cavities were prepared in the buccal and lingual surfaces of molars (n=9). Indirect composite inlays were luted into the cavities with either a self-adhesive or a self-etch resin cement. The teeth were sectioned bucco-lingually and the cement-dentin interface was analyzed by using micro-Raman spectroscopy (MRS) and scanning electron microscopy. Evolution of peak intensities of the Raman bands, collected from the functional groups corresponding to the resin monomer (C–O–C, 1113 cm-1) present in the cements, and the mineral content (P–O, 961 cm-1) in dentin were sigmoid shaped functions. A Boltzmann function (BF) was then fitted to the peaks encountered at 1113 cm-1 to estimate the resin cement diffusion into dentin. The BF identified a resin cement-dentin diffusion zone of 1.8±0.4 μm for the self-adhesive cement and 2.5±0.3 μm for the self-etch cement. This analysis allowed the authors to estimate the diffusion of the resin cements into the dentin. Fitting the MRS data to the BF contributed to and is relevant for future studies of the adhesive interface.

  11. NIOSH Manual of Analytical Methods (third edition). Fourth supplement

    Energy Technology Data Exchange (ETDEWEB)

    1990-08-15

    The NIOSH Manual of Analytical Methods, 3rd edition, was updated for the following chemicals: allyl-glycidyl-ether, 2-aminopyridine, aspartame, bromine, chlorine, n-butylamine, n-butyl-glycidyl-ether, carbon-dioxide, carbon-monoxide, chlorinated-camphene, chloroacetaldehyde, p-chlorophenol, crotonaldehyde, 1,1-dimethylhydrazine, dinitro-o-cresol, ethyl-acetate, ethyl-formate, ethylenimine, sodium-fluoride, hydrogen-fluoride, cryolite, sodium-hexafluoroaluminate, formic-acid, hexachlorobutadiene, hydrogen-cyanide, hydrogen-sulfide, isopropyl-acetate, isopropyl-ether, isopropyl-glycidyl-ether, lead, lead-oxide, maleic-anhydride, methyl-acetate, methyl-acrylate, methyl-tert-butyl ether, methyl-cellosolve-acetate, methylcyclohexanol, 4,4'-methylenedianiline, monomethylaniline, monomethylhydrazine, nitric-oxide, p-nitroaniline, phenyl-ether, phenyl-ether-biphenyl mixture, phenyl-glycidyl-ether, phenylhydrazine, phosphine, ronnel, sulfuryl-fluoride, talc, tributyl-phosphate, 1,1,2-trichloro-1,2,2-trifluoroethane, trimellitic-anhydride, triorthocresyl-phosphate, triphenyl-phosphate, and vinyl-acetate.

  12. 75 FR 49930 - Stakeholder Meeting Regarding Re-Evaluation of Currently Approved Total Coliform Analytical Methods

    Science.gov (United States)

    2010-08-16

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY Stakeholder Meeting Regarding Re-Evaluation of Currently Approved Total Coliform Analytical...) analytical methods. At these meetings, stakeholders will be given an opportunity to discuss...

  13. Evaluating protocols and analytical methods for peptide adsorption experiments.

    Science.gov (United States)

    Fears, Kenan P; Petrovykh, Dmitri Y; Clark, Thomas D

    2013-12-01

    This paper evaluates analytical techniques that are relevant for performing reliable quantitative analysis of peptide adsorption on surfaces. Two salient problems are addressed: determining the solution concentrations of model GG-X-GG, X5, and X10 oligopeptides (G = glycine, X = a natural amino acid), and quantitative analysis of these peptides following adsorption on surfaces. To establish a uniform methodology for measuring peptide concentrations in water across the entire GG-X-GG and X n series, three methods were assessed: UV spectroscopy of peptides having a C-terminal tyrosine, the bicinchoninic acid (BCA) protein assay, and amino acid (AA) analysis. Due to shortcomings or caveats associated with each of the different methods, none were effective at measuring concentrations across the entire range of representative model peptides. In general, reliable measurements were within 30% of the nominal concentration based on the weight of as-received lyophilized peptide. In quantitative analysis of model peptides adsorbed on surfaces, X-ray photoelectron spectroscopy (XPS) data for a series of lysine-based peptides (GGKGG, K5, and K10) on Au substrates, and for controls incubated in buffer in the absence of peptides, suggested a significant presence of aliphatic carbon species. Detailed analysis indicated that this carbonaceous contamination adsorbed from the atmosphere after the peptide deposition. The inferred adventitious nature of the observed aliphatic carbon was supported by control experiments in which substrates were sputter-cleaned by Ar(+) ions under ultra-high vacuum (UHV) then re-exposed to ambient air. In contrast to carbon contamination, no adventitious nitrogen species were detected on the controls; therefore, the relative surface densities of irreversibly-adsorbed peptides were calculated by normalizing the N/Au ratios by the average number of nitrogen atoms per residue. PMID:24706133

  14. Analytic compensation methods in dynamic tomography; Methodes analytiques de compensation des deformations en tomographie dynamique

    Energy Technology Data Exchange (ETDEWEB)

    Roux, S.; Desbat, L.; Koenig, A.; Grangeat, P. [Laboratoire TIMC-IMAG UMR CNRS 5525, Faculte de Medecine de Grenoble, 38 - La Tronche (France)]|[CEA Grenoble, Lab. Electronique et de Technologie de l' Informatique (LETI), 38 (France)

    2004-07-01

    Recent progresses in X-ray tomography allow to study some organs dynamically. The aim of this work is to analyze the deformation compensation algorithms used to integrate dynamical evolution models into the image reconstruction processes. An exact and efficient analytical method of movement compensation is presented and applied to simulated data. Abstract only. (J.S.)

  15. Intercalibration of analytical methods on marine environmental samples

    International Nuclear Information System (INIS)

    The pollution of the seas by various chemical substances constitutes nowadays one of the principal concerns of mankind. The International Atomic Energy Agency has organized in past years several intercomparison exercises in the framework of its Analytical Quality Control Service. The present intercomparison had a double aim: first, to give laboratories participating in this intercomparison an opportunity for checking their analytical performance. Secondly, to produce on the basis of the results of this intercomparison a reference material made of fish tissue which would be accurately certified with respect to many trace elements. Such a material could be used by analytical chemists to check the validity of new analytical procedures. In total, 53 laboratories from 29 countries reported results (585 laboratory means for 48 elements). 5 refs, 52 tabs

  16. Selected Parallel and Scalable Methods for Scientific Big Data Analytics

    OpenAIRE

    Riedel, Morris

    2015-01-01

    The goal of this talk is to inform participants about two concrete and widely used data analytics techniques that are suitable to analyse ‘big data’ for scientific and engineering applications. After a brief introduction to the general approach of using machine learning, data mining, and statistical computing in data analytics, the talk will offer details on the ‘clustering’ technique that partitions datasets into subgroups (i.e. clusters) previously unknown. From the broad class of available...

  17. Fuel Cycle Externalities: Analytical Methods and Issues, Report 2

    International Nuclear Information System (INIS)

    that also have not been fully addressed. This document contains two types of papers that seek to fill part of this void. Some of the papers describe analytical methods that can be applied to one of the five steps of the damage function approach. The other papers discuss some of the complex issues that arise in trying to estimate externalities. This report, the second in a series of eight reports, is part of a joint study by the U.S. Department of Energy (DOE) and the Commission of the European Communities (EC)* on the externalities of fuel cycles. Most of the papers in this report were originally written as working papers during the initial phases of this study. The papers provide descriptions of the (non-radiological) atmospheric dispersion modeling that the study uses; reviews much of the relevant literature on ecological and health effects, and on the economic valuation of those impacts; contains several papers on some of the more complex and contentious issues in estimating externalities; and describes a method for depicting the quality of scientific information that a study uses. The analytical methods and issues that this report discusses generally pertain to more than one of the fuel cycles, though not necessarily to all of them. The report is divided into six parts, each one focusing on a different subject area

  18. Estimating Fuel Cycle Externalities: Analytical Methods and Issues, Report 2

    Energy Technology Data Exchange (ETDEWEB)

    Barnthouse, L.W.; Cada, G.F.; Cheng, M.-D.; Easterly, C.E.; Kroodsma, R.L.; Lee, R.; Shriner, D.S.; Tolbert, V.R.; Turner, R.S.

    1994-07-01

    of complex issues that also have not been fully addressed. This document contains two types of papers that seek to fill part of this void. Some of the papers describe analytical methods that can be applied to one of the five steps of the damage function approach. The other papers discuss some of the complex issues that arise in trying to estimate externalities. This report, the second in a series of eight reports, is part of a joint study by the U.S. Department of Energy (DOE) and the Commission of the European Communities (EC)* on the externalities of fuel cycles. Most of the papers in this report were originally written as working papers during the initial phases of this study. The papers provide descriptions of the (non-radiological) atmospheric dispersion modeling that the study uses; reviews much of the relevant literature on ecological and health effects, and on the economic valuation of those impacts; contains several papers on some of the more complex and contentious issues in estimating externalities; and describes a method for depicting the quality of scientific information that a study uses. The analytical methods and issues that this report discusses generally pertain to more than one of the fuel cycles, though not necessarily to all of them. The report is divided into six parts, each one focusing on a different subject area.

  19. An analytical method for the measurement of nonviable bioaerosols.

    Science.gov (United States)

    Menetrez, M Y; Foarde, K K; Ensor, D S

    2001-10-01

    Exposures from indoor environments are a major issue for evaluating total long-term personal exposures to the fine fraction (airborne, IAQ could be significantly deteriorated. The airborne biocontaminants or their metabolites can induce irritational, allergic, infectious, and chemical responses in exposed individuals. Biocontaminants, such as some mold spores or pollen grains, because of their size and mass, settle rapidly within the indoor environment. Over time they may become nonviable and fragmented by the process of desiccation. Desiccated nonviable fragments of organisms are common and can be toxic or allergenic, depending upon the specific organism or organism component. Once these smaller and lighter fragments of biological PM become suspended in air, they have a greater tendency to stay suspended. Although some bioaerosols have been identified, few have been quantitatively studied for their prevalence within the total indoor PM with time, or for their affinity to penetrate indoors. This paper describes a preliminary research effort to develop a methodology for the measurement of nonviable biologically based PM, analyzing for mold and ragweed antigens and endotoxins. The research objectives include the development of a set of analytical methods and the comparison of impactor media and sample size, and the quantification of the relationship between outdoor and indoor levels of bioaerosols. Indoor and outdoor air samples were passed through an Andersen nonviable cascade impactor in which particles from 0.2 to 9.0 microm were collected and analyzed. The presence of mold, ragweed, and endotoxin was found in all eight size ranges. The presence of respirable particles of mold and pollen found in the fine particle size range from 0.2 to 5.25 microm is evidence of fragmentation of larger source particles that are known allergens. PMID:11686248

  20. Analytical and numerical methods for wave propagation in fluid media

    CERN Document Server

    Murawski, K

    2002-01-01

    This book surveys analytical and numerical techniques appropriate to the description of fluid motion with an emphasis on the most widely used techniques exhibiting the best performance.Analytical and numerical solutions to hyperbolic systems of wave equations are the primary focus of the book. In addition, many interesting wave phenomena in fluids are considered using examples such as acoustic waves, the emission of air pollutants, magnetohydrodynamic waves in the solar corona, solar wind interaction with the planet venus, and ion-acoustic solitons.

  1. Laser: a Tool for Optimization and Enhancement of Analytical Methods

    Energy Technology Data Exchange (ETDEWEB)

    Preisler, Jan

    1997-01-01

    In this work, we use lasers to enhance possibilities of laser desorption methods and to optimize coating procedure for capillary electrophoresis (CE). We use several different instrumental arrangements to characterize matrix-assisted laser desorption (MALD) at atmospheric pressure and in vacuum. In imaging mode, 488-nm argon-ion laser beam is deflected by two acousto-optic deflectors to scan plumes desorbed at atmospheric pressure via absorption. All absorbing species, including neutral molecules, are monitored. Interesting features, e.g. differences between the initial plume and subsequent plumes desorbed from the same spot, or the formation of two plumes from one laser shot are observed. Total plume absorbance can be correlated with the acoustic signal generated by the desorption event. A model equation for the plume velocity as a function of time is proposed. Alternatively, the use of a static laser beam for observation enables reliable determination of plume velocities even when they are very high. Static scattering detection reveals negative influence of particle spallation on MS signal. Ion formation during MALD was monitored using 193-nm light to photodissociate a portion of insulin ion plume. These results define the optimal conditions for desorbing analytes from matrices, as opposed to achieving a compromise between efficient desorption and efficient ionization as is practiced in mass spectrometry. In CE experiment, we examined changes in a poly(ethylene oxide) (PEO) coating by continuously monitoring the electroosmotic flow (EOF) in a fused-silica capillary during electrophoresis. An imaging CCD camera was used to follow the motion of a fluorescent neutral marker zone along the length of the capillary excited by 488-nm Ar-ion laser. The PEO coating was shown to reduce the velocity of EOF by more than an order of magnitude compared to a bare capillary at pH 7.0. The coating protocol was important, especially at an intermediate pH of 7.7. The increase of p

  2. Hanford environmental analytical methods: Methods as of March 1990. Volume 3, Appendix A2-I

    Energy Technology Data Exchange (ETDEWEB)

    Goheen, S.C.; McCulloch, M.; Daniel, J.L.

    1993-05-01

    This paper from the analytical laboratories at Hanford describes the method used to measure pH of single-shell tank core samples. Sludge or solid samples are mixed with deionized water. The pH electrode used combines both a sensor and reference electrode in one unit. The meter amplifies the input signal from the electrode and displays the pH visually.

  3. A brief introduction to analytical methods in nuclear forensics

    International Nuclear Information System (INIS)

    Nuclear forensic (NF) techniques are critical in responding to both environmental releases of nuclear materials and illicit trafficking activities involving both nuclear and counterfeit materials. Despite rising need, however, significant barriers exist to the future success of such research. This subset of analytical chemistry contains unique concerns (e.g. chronometry and impurity signatures), a wide variety of preparatory/instrumental approaches, and is in need of innovative solutions to current problems both in and out of the lab. The present work introduces existing NF research, development challenges and notes potential areas for advancement by highlighting several key analytical approaches. Examples of concerns and techniques discussed in this review include: chronometry, reference materials, separations, counting spectrometry, mass spectrometry and more. (author)

  4. Analytical methods of heat transfer compared with numerical methods as related to nuclear waste repositories

    International Nuclear Information System (INIS)

    Analytical methods were applied to the prediction of the far-field thermal impact of a nuclear waste repository. Specifically, the transformation of coordinates and the Kirchhoff transformation were used to solve one-dimensional nonlinear heat conduction problems. Calculations for the HLW and TRU nuclear waste with initial areal thermal loadings of 12 kW/acre and 0.7 kW/acre, respectively, are carried out for various models. Also, finite difference and finite element methods are applied. The last method is used to solve two-dimensional linear and nonlinear heat conduction problems. Results of the analysis are temperature distributions and temperature histories. Explicit analytical expressions of the maximum temperature rise as a function of the system parameters are presented. The theoretical approaches predict maximum temperature increases in the overburden with an error of 10%. When the finite solid one-dimensional NWR thermal problem is solved with generic salt and HLW thermal load as parameters, the maximum temperature rises predicted by the finite difference and finite element methods had maximum errors of 2.6 and 6.7%, respectively. In all the other cases the finite difference method also gave a smaller error than the finite element method

  5. MULTIPLE CRITERA METHODS WITH FOCUS ON ANALYTIC HIERARCHY PROCESS AND GROUP DECISION MAKING

    OpenAIRE

    Lidija Zadnik-Stirn; Petra Grošelj

    2010-01-01

    Managing natural resources is a group multiple criteria decision making problem. In this paper the analytic hierarchy process is the chosen method for handling the natural resource problems. The one decision maker problem is discussed and, three methods: the eigenvector method, data envelopment analysis method, and logarithmic least squares method are presented for the derivation of the priority vector. Further, the group analytic hierarchy process is discussed and six methods for the aggrega...

  6. Analytical methods for the evaluation of melamine contamination.

    Science.gov (United States)

    Cantor, Stuart L; Gupta, Abhay; Khan, Mansoor A

    2014-02-01

    There is an urgent need for the analysis of melamine in the global pharmaceutical supply chain to detect economically motivated adulteration or unintentional contamination using a simple, nondestructive analytical technique that confirms the extent of adulteration in a shorter time period. In this work, different analytical techniques (thermal analysis, X-ray diffraction, Fourier transform infrared (FT-IR), FT-Raman, and near-infrared (NIR) spectroscopy) were evaluated for their ability to detect a range of melamine levels in gelatin. While FT-IR and FT-Raman provided qualitative assessment of melamine contamination or adulteration, powder X-ray diffraction and NIR were able to detect and quantify the presence of melamine at levels as low as 1.0% w/w. Multivariate analysis of the NIR data yielded the most accurate model when three principal components were used. Data were pretreated using standard normal variate transformation to remove multiplicative interferences of scatter and particle size. The model had a root-mean-square error of calibration of 2.4 (R(2) = 0.99) and root-mean square error of prediction of 2.5 (R(2) = 0.96). The value of the paired t test for actual and predicted samples (1%-50% w/w) was 0.448 (p < 0.05), further indicating the robustness of the model. PMID:24327168

  7. Exact travelling wave solutions of the symmetric regularized long wave (SRLW using analytical methods

    Directory of Open Access Journals (Sweden)

    Jalil Manafian Heris

    2014-02-01

    Full Text Available In this article, we establish exact travelling wave solutions of the symmetric regularized long wave (SRLW by using analytical methods. The analytical methods are: the tanh-coth method and the sech^2 method which used to construct solitary wave solutions of nonlinear evolution equations. With the help of symbolic computation, we show that aforementioned methods provide a straightforward and powerful mathematical tool for solving nonlinear partial differential equations.

  8. 40 CFR 141.402 - Ground water source microbial monitoring and analytical methods.

    Science.gov (United States)

    2010-07-01

    ... by reference of the documents listed in footnotes 2-11 in accordance with 5 U.S.C. 552(a) and 1 CFR... monitoring and analytical methods. 141.402 Section 141.402 Protection of Environment ENVIRONMENTAL PROTECTION... Rule § 141.402 Ground water source microbial monitoring and analytical methods. (a) Triggered...

  9. A manual of analytical methods used at MINTEK

    International Nuclear Information System (INIS)

    The manual deals with various methods for a wide range of elemental analysis. Some of the methods that are used, include atomic absorption spectroscopy, optical emission spectroscopy and x-ray fluoresence spectroscopy. The basic charateristics of the method are given and the procedures are recorded step by step. One of the sections deals with methods associated with the recovery of uranium

  10. 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.

  11. Analytical method to accurately predict LMFBR core flow distribution

    International Nuclear Information System (INIS)

    An accurate and detailed representation of the flow distribution in LMFBR cores is very important as the starting point and basis of the thermal and structural core design. Previous experience indicated that the steady state and transient core design is as good as the core orificing; thus, a new orificing philosophy satisfying a priori all design constraints was developd. However, optimized orificing is a necessary, but not sufficient condition for achieving the optimum core flow distribution, which is affected by the hydraulic characteristics of the remainder of the primary system. Consequently, an analytical model of the overall primary system was developed, resulting in the CATFISH computer code, which, even though specifically written for LMFBRs, can be used for any reactor employing ducted assemblies

  12. Sterigmatocystin: occurrence in foodstuffs and analytical methods--an overview.

    Science.gov (United States)

    Versilovskis, Aleksandrs; De Saeger, Sarah

    2010-01-01

    Sterigmatocystin (STC) is a mycotoxin produced by fungi of many different Aspergillus species. Other species such as Bipolaris, Chaetomium, Emiricella are also able to produce STC. STC producing fungi were frequently isolated from different foodstuffs, while STC was regularly detected in grains, corn, bread, cheese, spices, coffee beans, soybeans, pistachio nuts, animal feed and silage. STC shows different toxicological, mutagenic and carcinogenic effects in animals and has been recognized as a 2B carcinogen (possible human carcinogen) by International Agency for Research on Cancer. There are more than 775 publications available in Scopus (and more than 505 in PubMed) mentioning STC, but there is no summary information available about STC occurrence and analysis in food. This review presents an overview of the worldwide information on the occurrence of STC in different foodstuffs during the last 40 years, and describes the progress made in analytical methodology for the determination of STC in food. PMID:19998385

  13. An analytic method for sensitivity analysis of complex systems

    CERN Document Server

    Zhu, Yueying; Li, Wei; Cai, Xu

    2016-01-01

    Sensitivity analysis is concerned with understanding how the model output depends on uncertainties (variances) in inputs and then identifies which inputs are important in contributing to the prediction imprecision. Uncertainty determination in output is the most crucial step in sensitivity analysis. In the present paper, an analytic expression, which can exactly evaluate the uncertainty in output as a function of the output's derivatives and inputs' central moments, is firstly deduced for general multivariate models with given relationship between output and inputs in terms of Taylor series expansion. A $\\gamma$-order relative uncertainty for output, denoted by $\\mathrm{R^{\\gamma}_v}$, is introduced to quantify the contributions of input uncertainty of different orders. On this basis, it is shown that the widely used approximation considering the first order contribution from the variance of input variable can satisfactorily express the output uncertainty only when the input variance is very small or the inpu...

  14. Intercalibration of analytical methods on marine environmental samples

    International Nuclear Information System (INIS)

    The analytical results reported by the 55 laboratories from 29 countries participating in this intercomparison have enabled to certify the concentration of 16 elements (As, Br, Ca, Cd, Co, Cr, Cu, Fe, Hg, Mg, Mn, Na, Rb, Se, Sr, Zn) in the mussel homogenate MA-M-2/TM. Information values could be established for 6 additional elements (Ag, Au, Cl, Pb, Sb, Sc). The atomic absorption spectroscopy was predominantly used in this intercomparison (45% of all determinations). It was followed by neutron activation analysis (28%), atomic emission spectroscopy (15%) and X-ray fluorescence (5%). The total number of outliers was moderate: 11.7% of all results. The number of outlying results by participating laboratories varied between 0 and 6

  15. Validation of analytical methods involved in dissolution assays: acceptance limits and decision methodologies.

    Science.gov (United States)

    Rozet, E; Ziemons, E; Marini, R D; Boulanger, B; Hubert, Ph

    2012-11-01

    Dissolution tests are key elements to ensure continuing product quality and performance. The ultimate goal of these tests is to assure consistent product quality within a defined set of specification criteria. Validation of an analytical method aimed at assessing the dissolution profile of products or at verifying pharmacopoeias compliance should demonstrate that this analytical method is able to correctly declare two dissolution profiles as similar or drug products as compliant with respect to their specifications. It is essential to ensure that these analytical methods are fit for their purpose. Method validation is aimed at providing this guarantee. However, even in the ICHQ2 guideline there is no information explaining how to decide whether the method under validation is valid for its final purpose or not. Are the entire validation criterion needed to ensure that a Quality Control (QC) analytical method for dissolution test is valid? What acceptance limits should be set on these criteria? How to decide about method's validity? These are the questions that this work aims at answering. Focus is made to comply with the current implementation of the Quality by Design (QbD) principles in the pharmaceutical industry in order to allow to correctly defining the Analytical Target Profile (ATP) of analytical methods involved in dissolution tests. Analytical method validation is then the natural demonstration that the developed methods are fit for their intended purpose and is not any more the inconsiderate checklist validation approach still generally performed to complete the filing required to obtain product marketing authorization. PMID:23084050

  16. Combined use of the EPA-QUAL2E simulation model and factor analysis to assess the source apportionment of point and non point loads of nutrients to surface waters.

    Science.gov (United States)

    Azzellino, A; Salvetti, R; Vismara, R; Bonomo, L

    2006-12-01

    Diffuse pollution is generally indirectly estimated by area and specific emission factors as function of land use. However in many cases these estimates were proven to be remarkably inaccurate. Aim of this study was to combine a water quality simulation model, (USEPA-QUAL2E) and Factor Analysis to increase the understanding of the water pollutants source apportionment. The study concerned two different watersheds, an upland area characterised by a very scarce agricultural use, and another area covering both the upland and the lowland physiographic regions. Particularly the lowland region is included in one of the most productive agricultural areas in Italy. By comparing instream measurements with QUAL2E simulations during dry and wet weather conditions, a good fit (errors +/-20%) was found for the dry weather scenario, whereas very poor was the model performance on the wet weather scenario. This was in the same way expected since the rainfall-driven pollutants scenario deviates significantly from QUAL2E general assumptions of constant emissions in steady state streamflow conditions. However the poor fit was also due to the scarcer reliability of the adopted non point emission estimates. Despite of approximations the model wet weather simulations enabled to estimate the non point contribution to the instream load at the rainfall event scale resolution. Such diffuse sources contribution was found around 80% in the area of extensive agricultural land use, and around 40% in the upland region. Factor Analysis applied to the instream measurements data shed light on the exchange from the groundwater to the surface water system that occurred in the upland region. The hypothesis of a groundwater contribution to the instream total load of nitrates was also supported by QUAL2E simulations that, when considering only the point loads, systematically underestimate the dry weather nitrate concentrations. The same pattern was not observed for the lowland region. PMID:16677687

  17. 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

  18. Survey of Technetium Analytical Production Methods Supporting Hanford Nuclear Materials Processing

    International Nuclear Information System (INIS)

    This document provides a historical survey of analytical methods used for measuring 99Tc in nuclear fuel reprocessing materials and wastes at Hanford. Method challenges including special sludge matrices tested are discussed. Special problems and recommendations are presented

  19. Analytic Matrix Method for the Study of Propagation Characteristics of a Bent Planar Waveguide

    Institute of Scientific and Technical Information of China (English)

    LIU Qing; CAO Zhuang-Qi; SHEN Qi-Shun; DOU Xiao-Ming; CHEN Ying-Li

    2000-01-01

    An analytic matrix method is used to analyze and accurately calculate the propagation constant and bendinglosses of a bent planar waveguide. This method gives not only a dispersion equation with explicit physical insight,but also accurate complex propagation constants.

  20. Five-point Element Scheme of Finite Analytic Method for Unsteady Groundwater Flow

    Institute of Scientific and Technical Information of China (English)

    Xiang Bo; Mi Xiao; Ji Changming; Luo Qingsong

    2007-01-01

    In order to improve the finite analytic method's adaptability for irregular unit, by using coordinates rotation technique this paper establishes a five-point element scheme of finite analytic method. It not only solves unsteady groundwater flow equation but also gives the boundary condition. This method can be used to calculate the three typical questions of groundwater. By compared with predecessor's computed result, the result of this method is more satisfactory.

  1. Carbonate measurements in PM10 near the marble quarries of Carrara (Italy) by infrared spectroscopy (FT-IR) and source apportionment by positive matrix factorization (PMF)

    Science.gov (United States)

    Cuccia, E.; Piazzalunga, A.; Bernardoni, V.; Brambilla, L.; Fermo, P.; Massabò, D.; Molteni, U.; Prati, P.; Valli, G.; Vecchi, R.

    2011-11-01

    The concentration of carbonates in atmospheric Particulate Matter (PM) is usually quite low. The surroundings of marble quarries are peculiar sites where the impact of carbonates in PM levels can be significant. We present here the results of a PM10 sampling campaign performed in Carrara (Italy). The town lies between the famous marble quarries and the harbour: about 1000 trucks per day transport marble blocks and debris from the quarries to the harbour passing through the town centre. PM10 was collected on daily basis on PTFE filters analyzed by Energy-Dispersive X-Ray Fluorescence (ED-XRF) and Ion-Chromatography (IC). Carbonate concentration was measured by a non-destructive Infrared Spectroscopy analysis (FT-IR). Time series of elemental (Na-Pb by ED-XRF), ionic (SO 42-, NH 4+ by ion-chromatography) and carbonate (by FT-IR) concentration values were merged in a unique data set and a PMF analysis singled out the major PM10 sources in the area. Marble transportation turned out to be the major pollution source in the town accounting to PM10 for about 36%; this corresponded to a CaCO 3 average level of about 8 μg m -3 during working days. The FT-IR analysis was a crucial part of the work and an ad-hoc analytical procedure was specifically set up, calibrated, and tested as described in the text.

  2. Description of JNC's analytical method and its performance for FBR cores

    International Nuclear Information System (INIS)

    The description of JNC's analytical method and its performance for FBR cores includes: an outline of JNC's Analytical System Compared with ERANOS; a standard data base for FBR Nuclear Design in JNC; JUPITER Critical Experiment; details of Analytical Method and Its Effects on JUPITER; performance of JNC Analytical System (effective multiplication factor keff, control rod worth, and sodium void reactivity); design accuracy of a 600 MWe-class FBR Core. JNC developed a consistent analytical system for FBR core evaluation, based on JENDL library, f-table method, and three dimensional diffusion/transport theory, which includes comprehensive sensitivity tools to improve the prediction accuracy of core parameters. JNC system was verified by analysis of JUPITER critical experiment, and other facilities. Its performance can be judged quite satisfactory for FBR-core design work, though there is room for further improvement, such as more detailed treatment of cross-section resonance regions

  3. Application of an analytical method for solution of thermal hydraulic conservation equations

    Energy Technology Data Exchange (ETDEWEB)

    Fakory, M.R. [Simulation, Systems & Services Technologies Company (S3 Technologies), Columbia, MD (United States)

    1995-09-01

    An analytical method has been developed and applied for solution of two-phase flow conservation equations. The test results for application of the model for simulation of BWR transients are presented and compared with the results obtained from application of the explicit method for integration of conservation equations. The test results show that with application of the analytical method for integration of conservation equations, the Courant limitation associated with explicit Euler method of integration was eliminated. The results obtained from application of the analytical method (with large time steps) agreed well with the results obtained from application of explicit method of integration (with time steps smaller than the size imposed by Courant limitation). The results demonstrate that application of the analytical approach significantly improves the numerical stability and computational efficiency.

  4. Tank 48H Waste Composition and Results of Investigation of Analytical Methods

    Energy Technology Data Exchange (ETDEWEB)

    Walker , D.D. [Westinghouse Savannah River Company, AIKEN, SC (United States)

    1997-04-02

    This report serves two purposes. First, it documents the analytical results of Tank 48H samples taken between April and August 1996. Second, it describes investigations of the precision of the sampling and analytical methods used on the Tank 48H samples.

  5. Manual of analytical methods for the Industrial Hygiene Chemistry Laboratory

    International Nuclear Information System (INIS)

    This Manual is compiled from techniques used in the Industrial Hygiene Chemistry Laboratory of Sandia National Laboratories in Albuquerque, New Mexico. The procedures are similar to those used in other laboratories devoted to industrial hygiene practices. Some of the methods are standard; some, modified to suit our needs; and still others, developed at Sandia. The authors have attempted to present all methods in a simple and concise manner but in sufficient detail to make them readily usable. It is not to be inferred that these methods are universal for any type of sample, but they have been found very reliable for the types of samples mentioned

  6. Analytical method for promoting process capability of shock absorption steel

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Mechanical properties and low cycle fatigue are two factors that must be considered in developing new type steel for shock absorption. Process capability and process control are significant factors in achieving the purpose of research and development programs. Often-used evaluation methods failed to measure process yield and process centering; so this paper uses Taguchi loss function as basis to establish an evaluation method and the steps for assessing the quality of mechanical properties and process control of an iron and steel manufacturer. The establishment of this method can serve the research and development and manufacturing industry and lay a foundation in enhancing its process control ability to select better manufacturing processes that are more reliable than decision making by using the other commonly used methods.

  7. Base flow separation: A comparison of analytical and mass balance methods

    Science.gov (United States)

    Lott, Darline A.; Stewart, Mark T.

    2016-04-01

    Base flow is the ground water contribution to stream flow. Many activities, such as water resource management, calibrating hydrological and climate models, and studies of basin hydrology, require good estimates of base flow. The base flow component of stream flow is usually determined by separating a stream hydrograph into two components, base flow and runoff. Analytical methods, mathematical functions or algorithms used to calculate base flow directly from discharge, are the most widely used base flow separation methods and are often used without calibration to basin or gage-specific parameters other than basin area. In this study, six analytical methods are compared to a mass balance method, the conductivity mass-balance (CMB) method. The base flow index (BFI) values for 35 stream gages are obtained from each of the seven methods with each gage having at least two consecutive years of specific conductance data and 30 years of continuous discharge data. BFI is cumulative base flow divided by cumulative total discharge over the period of record of analysis. The BFI value is dimensionless, and always varies from 0 to 1. Areas of basins used in this study range from 27 km2 to 68,117 km2. BFI was first determined for the uncalibrated analytical methods. The parameters of each analytical method were then calibrated to produce BFI values as close to the CMB derived BFI values as possible. One of the methods, the power function (aQb + cQ) method, is inherently calibrated and was not recalibrated. The uncalibrated analytical methods have an average correlation coefficient of 0.43 when compared to CMB-derived values, and an average correlation coefficient of 0.93 when calibrated with the CMB method. Once calibrated, the analytical methods can closely reproduce the base flow values of a mass balance method. Therefore, it is recommended that analytical methods be calibrated against tracer or mass balance methods.

  8. Analytical Model Analysis Of Distributed Cooperative Spectrum Sensing Method

    Directory of Open Access Journals (Sweden)

    Ravi Prakash Shukla

    2012-05-01

    Full Text Available Spectrum sensing is a key function of cognitive radio to prevent the harmful interference with licensed users and identify the available spectrum for improving the spectrum’s utilization. Various methods for spectrum sensing control, such as deciding which sensors should perform sensing simultaneously and finding the appropriate trade-off between probability of misdetection and false alarm rate, are described. However, detection performance in practice is often compromised with multipath fading, shadowing and receiver uncertainty issues. To mitigate the impact of these issues, cooperative spectrum sensing has been shown to be an effective method to improve the detection performance by exploiting spatial diversity.

  9. A new robust method for the treatment of analytical data

    International Nuclear Information System (INIS)

    A new robust method is proposed for the calculation of the median and the relative standard deviation for a set of data containing unsymmetrically placed outliers. Examples of the advantages of the new method are given, the findings being confirmed by Monte Carlo tests. At Mintek mass-spectrometric data are often unsymmetrical, and all outliers are often at one of the extremities, either all high or all low. In some instances the outliers can be seen visually, and would therefore be rejected on sight. However, when large sets of results are processed, such as those from mass-spectrometric, X-ray fluorescence, and neutron-activation analyses, or in fields such as the assignment of values to reference materials, the sets of results are often too large for visual inspection and are processed within the computer

  10. 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

  11. Analytical Methods for Determination of the Oxidative Status in Oils

    OpenAIRE

    Semb, Thea Norveel

    2012-01-01

    In industry today standard oxidative quality parameters are based on measurements of primary and secondary oxidation products, measured by PV and AV respectively. These methods are all prone to limitations and weaknesses, and their suitability for application on marine oils is not well documented. An increase in fish oil products with added flavor, color compounds, antioxidants and vitamins has entered the market in recent years. However, no documentation on the effect of these additives on t...

  12. A Vocal-Based Analytical Method for Goose Behaviour Recognition

    OpenAIRE

    Henrik Karstoft; Ole Green; Kim Arild Steen; Ole Roland Therkildsen

    2012-01-01

    Since human-wildlife conflicts are increasing, the development of cost-effective methods for reducing damage or conflict levels is important in wildlife management. A wide range of devices to detect and deter animals causing conflict are used for this purpose, although their effectiveness is often highly variable, due to habituation to disruptive or disturbing stimuli. Automated recognition of behaviours could form a critical component of a system capable of altering the disruptive stimuli to...

  13. The analytic method for calculating the control rod worth

    International Nuclear Information System (INIS)

    We calculated the control rod worth in this paper. To avoid complexity, we did not consider burnable poisons and soluble boron. The system was localized within one assembly. The control rod was treated as not an absorber but an another boundary. Thus all of the group constants were unchanged before and after control rod insertion. And we discussed the method for calculation of the reactivity of the whole core

  14. Testing of analytical and purification methods for HTR helium coolant

    International Nuclear Information System (INIS)

    The paper describes a method of determination of gaseous impurities (H2, O2, N2, CO, CH4, CO2) in high purity helium as well as the methods of gaseous impurities removal. A device used for the determination was the Master GC type gas chromatograph with a helium detection unit and a ShinCarbon ST column. A temperature program was used to improve the conditions of separation and to reach maximum response of the detector. The obtained limits of detection defined as three times the standard deviation of the background value of tested components are H2 0.3 vppm, O2 0.4 vppm, N2 0.2 vppm, CO 2 vppm, CH4 3 vppm, CO2 2 vppm. Analysis time is less than 20 min. The developed method will be used for checking the purity of helium environment in the experimental loop to model experimental conditions in the high temperature gas cooled reactor (HTGR). Within the scope of the proposal of the helium purification system, the efficiency of removing selected impurities (CO, CO2, CH4) on adsorbents (based on zeolites and active carbon) was tested. A laboratory scale apparatus and an FTIR spectrometer were used for experiments.

  15. An improved analytical method for plate-fluid frequency determination

    International Nuclear Information System (INIS)

    The rectangular thin elastic plates are broadly used as structural components of different thin-walled parallelepiped tanks, containing an acoustic liquid and subjected to dynamic loads. The important problem - to determine the basic natural frequencies of the plate, taking into account its interaction with the internal fluid, has been considered by A.I. Pretlove and A. Craggs (1970) suggested an original approximate method. The philosophy of the method proposed is to take into account only some harmonics (but the most essential ones) in the motion equation of the plate, considering in the same time in original manner the R.H. Sides which describe the plate-fluid interaction. The plate considered is free supported. Following their suggestion, only the main co-ordinates q11(t) and q31(t), has to be considered presupposing with this, that the plate size along the x-direction always has to be considerably longer. This preference over the x-direction brakes the geometric symmetry, and as a consequence, their smart method loses its generality. As it is well known (from the plate stability/dynamics theory) the wave forming has its own law, which in the article under discussion possibly are not quite well observed. From another side, in connection with the assumption that the fluid-structure interaction (FSI) will be adiabatic process, they express some suspect on the results obtained

  16. Analytical methods in heavy quark physics and the case of $\\tau_{1/2}(w)$

    OpenAIRE

    Yaouanc, A. Le

    2004-01-01

    Analytical methods in heavy quark physics are shortly reviewed, with emphasis on the problems of dynamical calculations. Then, attention is attracted to the various difficulties raised by a tentative experimental determination of $\\tau_{1/2}$

  17. Approximate Analytic Solutions for the Two-Phase Stefan Problem Using the Adomian Decomposition Method

    Directory of Open Access Journals (Sweden)

    Xiao-Ying Qin

    2014-01-01

    Full Text Available An Adomian decomposition method (ADM is applied to solve a two-phase Stefan problem that describes the pure metal solidification process. In contrast to traditional analytical methods, ADM avoids complex mathematical derivations and does not require coordinate transformation for elimination of the unknown moving boundary. Based on polynomial approximations for some known and unknown boundary functions, approximate analytic solutions for the model with undetermined coefficients are obtained using ADM. Substitution of these expressions into other equations and boundary conditions of the model generates some function identities with the undetermined coefficients. By determining these coefficients, approximate analytic solutions for the model are obtained. A concrete example of the solution shows that this method can easily be implemented in MATLAB and has a fast convergence rate. This is an efficient method for finding approximate analytic solutions for the Stefan and the inverse Stefan problems.

  18. A Vocal-Based Analytical Method for Goose Behaviour Recognition

    Directory of Open Access Journals (Sweden)

    Henrik Karstoft

    2012-03-01

    Full Text Available Since human-wildlife conflicts are increasing, the development of cost-effective methods for reducing damage or conflict levels is important in wildlife management. A wide range of devices to detect and deter animals causing conflict are used for this purpose, although their effectiveness is often highly variable, due to habituation to disruptive or disturbing stimuli. Automated recognition of behaviours could form a critical component of a system capable of altering the disruptive stimuli to avoid this. In this paper we present a novel method to automatically recognise goose behaviour based on vocalisations from flocks of free-living barnacle geese (Branta leucopsis. The geese were observed and recorded in a natural environment, using a shielded shotgun microphone. The classification used Support Vector Machines (SVMs, which had been trained with labeled data. Greenwood Function Cepstral Coefficients (GFCC were used as features for the pattern recognition algorithm, as they can be adjusted to the hearing capabilities of different species. Three behaviours are classified based in this approach, and the method achieves a good recognition of foraging behaviour (86–97% sensitivity, 89–98% precision and a reasonable recognition of flushing (79–86%, 66–80% and landing behaviour(73–91%, 79–92%. The Support Vector Machine has proven to be a robust classifier for this kind of classification, as generality and non-linearcapabilities are important. We conclude that vocalisations can be used to automatically detect behaviour of conflict wildlife species, and as such, may be used as an integrated part of awildlife management system.

  19. A vocal-based analytical method for goose behaviour recognition.

    Science.gov (United States)

    Steen, Kim Arild; Therkildsen, Ole Roland; Karstoft, Henrik; Green, Ole

    2012-01-01

    Since human-wildlife conflicts are increasing, the development of cost-effective methods for reducing damage or conflict levels is important in wildlife management. A wide range of devices to detect and deter animals causing conflict are used for this purpose, although their effectiveness is often highly variable, due to habituation to disruptive or disturbing stimuli. Automated recognition of behaviours could form a critical component of a system capable of altering the disruptive stimuli to avoid this. In this paper we present a novel method to automatically recognise goose behaviour based on vocalisations from flocks of free-living barnacle geese (Branta leucopsis). The geese were observed and recorded in a natural environment, using a shielded shotgun microphone. The classification used Support Vector Machines (SVMs), which had been trained with labeled data. Greenwood Function Cepstral Coefficients (GFCC) were used as features for the pattern recognition algorithm, as they can be adjusted to the hearing capabilities of different species. Three behaviours are classified based in this approach, and the method achieves a good recognition of foraging behaviour (86-97% sensitivity, 89-98% precision) and a reasonable recognition of flushing (79-86%, 66-80%) and landing behaviour(73-91%, 79-92%). The Support Vector Machine has proven to be a robust classifier for this kind of classification, as generality and non-linear capabilities are important. We conclude that vocalisations can be used to automatically detect behaviour of conflict wildlife species, and as such, may be used as an integrated part of a wildlife management system. PMID:22737037

  20. Analytical method for optimization of maintenance policy based on available system failure data

    International Nuclear Information System (INIS)

    An analytical optimization method for preventive maintenance (PM) policy with minimal repair at failure, periodic maintenance, and replacement is proposed for systems with historical failure time data influenced by a current PM policy. The method includes a new imperfect PM model based on Weibull distribution and incorporates the current maintenance interval T0 and the optimal maintenance interval T to be found. The Weibull parameters are analytically estimated using maximum likelihood estimation. Based on this model, the optimal number of PM and the optimal maintenance interval for minimizing the expected cost over an infinite time horizon are also analytically determined. A number of examples are presented involving different failure time data and current maintenance intervals to analyze how the proposed analytical optimization method for periodic PM policy performances in response to changes in the distribution of the failure data and the current maintenance interval. - Highlights: • An analytical optimization method for preventive maintenance (PM) policy is proposed. • A new imperfect PM model is developed. • The Weibull parameters are analytically estimated using maximum likelihood. • The optimal maintenance interval and number of PM are also analytically determined. • The model is validated by several numerical examples

  1. Traveling wave analysis of partial differential equations numerical and analytical methods with Matlab and Maple

    CERN Document Server

    Griffiths, Graham

    2010-01-01

    Although the Partial Differential Equations (PDE) models that are now studied are usually beyond traditional mathematical analysis, the numerical methods that are being developed and used require testing and validation. This is often done with PDEs that have known, exact, analytical solutions. The development of analytical solutions is also an active area of research, with many advances being reported recently, particularly traveling wave solutions for nonlinear evolutionary PDEs. Thus, the current development of analytical solutions directly supports the development of numerical methods by p

  2. Analytical Methods for Environmental Risk Assessment of Acid Sulfate Soils: A Review

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Assessment of acid sulfate soil risk is an important step for acid sulfate soil management and its reliability depends very much on the suitability and accuracy of various analytical methods for estimating sulfide-derived potential acidity, actual acidity and acid-neutralizing capacity in acid sulfate soils. This paper critically reviews various analytical methods that are currently used for determination of the above parameters, as well as their implications for environmental risk assessment of acid sulfate soils.

  3. Critical node treatment in the analytic function expansion method for Pin Power Reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Z. [Rice University, MS 318, 6100 Main Street, Houston, TX 77005 (United States); Xu, Y. [Argonne National Laboratory, 9700 South Case Ave., Argonne, IL 60439 (United States); Downar, T. [Department of Nuclear Engineering, University of Michigan, 2355 Bonisteel blvd., Ann Arbor, MI 48109 (United States)

    2013-07-01

    Pin Power Reconstruction (PPR) was implemented in PARCS using the eight term analytic function expansion method (AFEN). This method has been demonstrated to be both accurate and efficient. However, similar to all the methods involving analytic functions, such as the analytic node method (ANM) and AFEN for nodal solution, the use of AFEN for PPR also has potential numerical issue with critical nodes. The conventional analytic functions are trigonometric or hyperbolic sine or cosine functions with an angular frequency proportional to buckling. For a critic al node the buckling is zero and the sine functions becomes zero, and the cosine function become unity. In this case, the eight terms of the analytic functions are no longer distinguishable from ea ch other which makes their corresponding coefficients can no longer be determined uniquely. The mode flux distribution of critical node can be linear while the conventional analytic functions can only express a uniform distribution. If there is critical or near critical node in a plane, the reconstructed pin power distribution is often be shown negative or very large values using the conventional method. In this paper, we propose a new method to avoid the numerical problem wit h critical nodes which uses modified trigonometric or hyperbolic sine functions which are the ratio of trigonometric or hyperbolic sine and its angular frequency. If there are no critical or near critical nodes present, the new pin power reconstruction method with modified analytic functions are equivalent to the conventional analytic functions. The new method is demonstrated using the L336C5 benchmark problem. (authors)

  4. Critical node treatment in the analytic function expansion method for Pin Power Reconstruction

    International Nuclear Information System (INIS)

    Pin Power Reconstruction (PPR) was implemented in PARCS using the eight term analytic function expansion method (AFEN). This method has been demonstrated to be both accurate and efficient. However, similar to all the methods involving analytic functions, such as the analytic node method (ANM) and AFEN for nodal solution, the use of AFEN for PPR also has potential numerical issue with critical nodes. The conventional analytic functions are trigonometric or hyperbolic sine or cosine functions with an angular frequency proportional to buckling. For a critic al node the buckling is zero and the sine functions becomes zero, and the cosine function become unity. In this case, the eight terms of the analytic functions are no longer distinguishable from ea ch other which makes their corresponding coefficients can no longer be determined uniquely. The mode flux distribution of critical node can be linear while the conventional analytic functions can only express a uniform distribution. If there is critical or near critical node in a plane, the reconstructed pin power distribution is often be shown negative or very large values using the conventional method. In this paper, we propose a new method to avoid the numerical problem wit h critical nodes which uses modified trigonometric or hyperbolic sine functions which are the ratio of trigonometric or hyperbolic sine and its angular frequency. If there are no critical or near critical nodes present, the new pin power reconstruction method with modified analytic functions are equivalent to the conventional analytic functions. The new method is demonstrated using the L336C5 benchmark problem. (authors)

  5. Joint Monitoring Programme (JMP). Overview of analytical methods employed by JMP in Norway 1981-1987

    OpenAIRE

    Green, N.

    1988-01-01

    Brief descriptions are given of the analytical methods employed by Norway under the Joint Monitoring Programme (JMP) and in cooperation with the International Council for the exploration of the Sea (ICES). Methods concern determination of trace metals and chlorinated hydrocarbons in sea water, sea bed sediment and marine organisms. Included are the detection limits, analytical laborator- ies, and references to the intercalibration exercises that applied to samples collected 1981-86.

  6. Development of a methodology examining the behaviours of VOCs source apportionment with micro-meteorology analysis in an urban and industrial area

    International Nuclear Information System (INIS)

    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. - Highlights: ► Several PMF factors were associated with mix of sources. ► We demonstrated different dynamic behaviours of the contributions of PMF factors. ► We used micro-meteorological parameters to distinguish the sources near ground from those in the upper part of surface layer. - This paper gives a method to study dynamical behaviours of VOCs source contributions.

  7. Analytic method for geometrical parameter correction of planar HPGe detector

    International Nuclear Information System (INIS)

    A numerical integration formula was introduced to calculate the response of planar HPGe detector to photons emitted from point source. Then the formula was used to correct the geometrical parameter of planar HPGe detector. 241Am and 137Cs point sources were placed at a certain distance (1-20 cm) away from entrance window to get the corresponding detection efficiency. The detection parameters were calculated in weighted least square fitting using the formula with the experimental efficiencies as formula results. This correction method was accurate and timesaving. The simulation result from MCNP using the corrected parameters shows that the relative deviations between simulation and experimental efficiencies are less than 1% for 59.5 and 661.6 keV photons with the distance of 1-20 cm. (authors)

  8. Manual of analytical methods for the Environmental Health Laboratory

    International Nuclear Information System (INIS)

    The manual contains four sections: absorption spectrophotometry; general radiochemical procedures; instrumental analysis; and calibration of field instruments. Included in the individual analyses using absorption spectrophotometry is one for total iodine in oil. Radiochemical procedures are given for: actinides in urine and water; 137Cs in soil and vegetation; 137Cs in soil, urine, vegetation, and water; enriched uranium in urine; gross beta activity in soil, urine, vegetation, and water; plutonium in urine and soil; 210Po in urine and water; 24Na in air, blood, urine, and water; 90Sr in soil, vegetation, and water; tritium in urine, water, and on swipes; and total uranium on fallout trays and in soil, urine, and water. Among the individual instrumental analyses is a spectrographic method for determining beryllium in air samples and swipes. (U.S.)

  9. Analytical Chemistry Laboratory (ACL) procedure compendium. Volume 4, Organic methods

    Energy Technology Data Exchange (ETDEWEB)

    1993-08-01

    This interim notice covers the following: extractable organic halides in solids, total organic halides, analysis by gas chromatography/Fourier transform-infrared spectroscopy, hexadecane extracts for volatile organic compounds, GC/MS analysis of VOCs, GC/MS analysis of methanol extracts of cryogenic vapor samples, screening of semivolatile organic extracts, GPC cleanup for semivolatiles, sample preparation for GC/MS for semi-VOCs, analysis for pesticides/PCBs by GC with electron capture detection, sample preparation for pesticides/PCBs in water and soil sediment, report preparation, Florisil column cleanup for pesticide/PCBs, silica gel and acid-base partition cleanup of samples for semi-VOCs, concentrate acid wash cleanup, carbon determination in solids using Coulometrics` CO{sub 2} coulometer, determination of total carbon/total organic carbon/total inorganic carbon in radioactive liquids/soils/sludges by hot persulfate method, analysis of solids for carbonates using Coulometrics` Model 5011 coulometer, and soxhlet extraction.

  10. 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

  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

  12. Modeling air quality during the California Regional PM 10/PM 2.5 Air Quality Study (CPRAQS) using the UCD/CIT source-oriented air quality model - Part III. Regional source apportionment of secondary and total airborne particulate matter

    Science.gov (United States)

    Ying, Qi; Lu, Jin; Kleeman, Michael

    A comprehensive air quality modeling project was carried out to simulate regional source contributions to secondary and total (=primary + secondary) airborne particle concentrations in California's Central Valley. A three-week stagnation episode lasting from December 15, 2000 to January 7, 2001, was chosen for study using the air quality and meteorological data collected during the California Regional PM 10/PM 2.5 Air Quality Study (CRPAQS). The UCD/CIT mechanistic air quality model was used with explicit decomposition of the gas phase reaction chemistry to track source contributions to secondary PM. Inert artificial tracers were used with an internal mixture representation to track source contributions to primary PM. Both primary and secondary source apportionment calculations were performed for 15 size fractions ranging from 0.01 to 10 μm particle diameters. Primary and secondary source contributions were resolved for fugitive dust, road dust, diesel engines, catalyst equipped gasoline engines, non-catalyst equipped gasoline engines, wood burning, food cooking, high sulfur fuel combustion, and other anthropogenic sources. Diesel engines were identified as the largest source of secondary nitrate in central California during the study episode, accounting for approximately 40% of the total PM 2.5 nitrate. Catalyst equipped gasoline engines were also significant, contributing approximately 20% of the total secondary PM 2.5 nitrate. Agricultural sources were the dominant source of secondary ammonium ion. Sharp gradients of PM concentrations were predicted around major urban areas. The relative source contributions to PM 2.5 from each source category in urban areas differ from those in rural areas, due to the dominance of primary OC in urban locations and secondary nitrate in the rural areas. The source contributions to ultra-fine particle mass PM 0.1 also show clear urban/rural differences. Wood smoke was found to be the major source of PM 0.1 in urban areas while

  13. A simple parallel analytical method of prenatal screening.

    Science.gov (United States)

    Li, Ding; Yang, Hao; Zhang, Wen-Hong; Pan, Hao; Wen, Dong-Qing; Han, Feng-Chan; Guo, Hui-Fang; Wang, Xiao-Ming; Yan, Xiao-Jun

    2006-01-01

    Protein microarray has progressed rapidly in the past few years, but it is still hard to popularize it in many developing countries or small hospitals owing to the technical expertise required in practice. We developed a cheap and easy-to-use protein microarray based on dot immunogold filtration assay for parallel analysis of ToRCH-related antibodies including Toxoplasma gondii, rubella virus, cytomegalovirus and herpes simplex virus type 1 and 2 in sera of pregnant women. It does not require any expensive instruments and the assay results can be clearly recognized by the naked eye. We analyzed 186 random sera of outpatients at the gynecological department with our microarray and commercial ELISA kit, and the results showed there was no significant difference between the two detection methods. Validated by clinical application, the microarray is easy to use and has a unique advantage in cost and time. It is more suitable for mass prenatal screening or epidemiological screening than the ELISA format. PMID:16791006

  14. Analytic study of the Tadoma method: background and preliminary results.

    Science.gov (United States)

    Norton, S J; Schultz, M C; Reed, C M; Braida, L D; Durlach, N I; Rabinowitz, W M; Chomsky, C

    1977-09-01

    Certain deaf-blind persons have been taught, through the Tadoma method of speechreading, to use vibrotactile cues from the face and neck to understand speech. This paper reports the results of preliminary tests of the speechreading ability of one adult Tadoma user. The tests were of four major types: (1) discrimination of speech stimuli; (2) recognition of words in isolation and in sentences; (3) interpretation of prosodic and syntactic features in sentences; and (4) comprehension of written (Braille) and oral speech. Words in highly contextual environments were much better perceived than were words in low-context environments. Many of the word errors involved phonemic substitutions which shared articulatory features with the target phonemes, with a higher error rate for vowels than consonants. Relative to performance on word-recognition tests, performance on some of the discrimination tests was worse than expected. Perception of sentences appeared to be mildly sensitive to rate of talking and to speaker differences. Results of the tests on perception of prosodic and syntactic features, while inconclusive, indicate that many of the features tested were not used in interpreting sentences. On an English comprehension test, a higher score was obtained for items administered in Braille than through oral presentation. PMID:904318

  15. Analytical methods for 2,4-D (Dichlorophenoxyacetic acid) determination

    International Nuclear Information System (INIS)

    The 2,4-D herbicide is one of the main pesticides for controlling the bad grass in crops such as the water undergrowth. In Mexico the allowed bound of this pesticide is 0.05 mg/l in water of 2,4-D so it is required to have methods trusts and exacts, which can used in order to detected low concentration of it. In this work we show some for the conventional techniques and for establishing the 2,4-D concentrations. The UV-Vis spectrometer and liquids chromatography due that they are the most common used nowadays. Beside, we introduce a now developed technique, which is based on the neutronic activation analysis. Though use of the UV-Vis spectrometer technique it was possible target the concentrations interval between 1 and 200 mg/l. In the liquids chromatography interval was between 0.1 and 0.9, and by the neutronic activation analysis the interval was between 0.01 and 200 mg/l. (Author)

  16. Development of rapid analytical methods for Am-241

    International Nuclear Information System (INIS)

    In the framework of the IAEA Co-ordinated Research Programme on Rapid Instrumental and Separation Methods for Monitoring Radionuclides in Food and Environmental Samples, the original programme of the Department of Nuclear Chemistry was modified at the first RCM in Warsaw, Poland, so that the part dealing with Sr-89,90 was to be omitted. In the first phase of the work (reported in Warsaw) the limits of detection for 241Am by gamma spectrometry of its 35.9% abundant 59.5 keV gamma ray were determined for two detectors, i.e. a low energy photon detector (LEPD) of the maximum size currently commercially available (disc 50 mm diameter, 20 mm deep), and an HP Ge well-type detector with a 5 ml hole. It was intended that the major use of the well-type detector would be to measure 241Am by gamma spectroscopy in small concentrates separated by relatively simple and rapid radiochemical procedures from large bulk samples, thus taking advantage of the high efficiency of the detector combined with a large initial sample size

  17. An analytical method of estimating Value-at-Risk on the Belgrade Stock Exchange

    Directory of Open Access Journals (Sweden)

    Obadović Milica D.

    2009-01-01

    Full Text Available This paper presents market risk evaluation for a portfolio consisting of shares that are continuously traded on the Belgrade Stock Exchange, by applying the Value-at-Risk model - the analytical method. It describes the manner of analytical method application and compares the results obtained by implementing this method at different confidence levels. Method verification was carried out on the basis of the failure rate that demonstrated the confidence level for which this method was acceptable in view of the given conditions.

  18. An introduction to clinical microeconomic analysis: purposes and analytic methods.

    Science.gov (United States)

    Weintraub, W S; Mauldin, P D; Becker, E R

    1994-06-01

    The recent concern with health care economics has fostered the development of a new discipline that is generally called clinical microeconomics. This is a discipline in which microeconomic methods are used to study the economics of specific medical therapies. It is possible to perform stand alone cost analyses, but more profound insight into the medical decision making process may be accomplished by combining cost studies with measures of outcome. This is most often accomplished with cost-effectiveness or cost-utility studies. In cost-effectiveness studies there is one measure of outcome, often death. In cost-utility studies there are multiple measures of outcome, which must be grouped together to give an overall picture of outcome or utility. There are theoretical limitations to the determination of utility that must be accepted to perform this type of analysis. A summary statement of outcome is quality adjusted life years (QALYs), which is utility time socially discounted survival. Discounting is used because people value a year of future life less than a year of present life. Costs are made up of in-hospital direct, professional, follow-up direct, and follow-up indirect costs. Direct costs are for medical services. Indirect costs reflect opportunity costs such as lost time at work. Cost estimates are often based on marginal costs, or the cost for one additional procedure of the same type. Finally an overall statistic may be generated as cost per unit increase in effectiveness, such as dollars per QALY.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:10151059

  19. Development of an Analytical System for Determination of Free Acid via a Joint Method Combining Density and Conductivity Measurement

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Determination of free acid plays an important role in spent nuclear fuel reprocessing. It is necessary to develop a rapid analytical device and method for measuring free acid. A novel analytical system and method was studied to monitor the acidity

  20. Ernst Equation and Riemann Surfaces: Analytical and Numerical Methods

    International Nuclear Information System (INIS)

    tensor components. The first two chapters of this book are devoted to some basic ideas: in the introductory chapter 1 the authors discuss the concept of integrability, comparing the integrability of the vacuum Ernst equation with the integrability of nonlinear equations of Korteweg-de Vries (KdV) type, while in chapter 2 they describe various circumstances in which the vacuum Ernst equation has been determined to be relevant, not only in connection with gravitation but also, for example, in the construction of solutions of the self-dual Yang-Mills equations. It is also in this chapter that one of several equivalent linear systems for the Ernst equation is described. The next two chapters are devoted to Dmitry Korotkin's concept of algebro-geometric solutions of a linear system: in chapter 3 the structure of such solutions of the vacuum Ernst equation, which involve Riemann theta functions of hyperelliptic algebraic curves of any genus, is contrasted with the periodic structure of such solutions of the KdV equation. How such solutions can be obtained, for example, by solving a matrix Riemann-Hilbert problem and how the metric tensor of the associated spacetime can be evaluated is described in detail. In chapter 4 the asymptotic behaviour and the similarity structure of the general algebro-geometric solutions of the Ernst equation are described, and the relationship of such solutions to the perhaps more familiar multi-soliton solutions is discussed. The next three chapters are based upon the authors' own published research: in chapter 5 it is shown that a problem involving counter-rotating infinitely thin disks of matter can be solved in terms of genus two Riemann theta functions, while in chapter 6 the authors describe numerical methods that facilitate the construction of such solutions, and in chapter 7 three-dimensional graphs are displayed that depict all metrical fields of the associated spacetime. Finally, in chapter 8, the difficulties associated with extending the

  1. Ernst Equation and Riemann Surfaces: Analytical and Numerical Methods

    Energy Technology Data Exchange (ETDEWEB)

    Ernst, Frederick J [FJE Enterprises, 511 County Route 59, Potsdam, NY 13676 (United States)

    2007-06-18

    source can be represented by discontinuities in the metric tensor components. The first two chapters of this book are devoted to some basic ideas: in the introductory chapter 1 the authors discuss the concept of integrability, comparing the integrability of the vacuum Ernst equation with the integrability of nonlinear equations of Korteweg-de Vries (KdV) type, while in chapter 2 they describe various circumstances in which the vacuum Ernst equation has been determined to be relevant, not only in connection with gravitation but also, for example, in the construction of solutions of the self-dual Yang-Mills equations. It is also in this chapter that one of several equivalent linear systems for the Ernst equation is described. The next two chapters are devoted to Dmitry Korotkin's concept of algebro-geometric solutions of a linear system: in chapter 3 the structure of such solutions of the vacuum Ernst equation, which involve Riemann theta functions of hyperelliptic algebraic curves of any genus, is contrasted with the periodic structure of such solutions of the KdV equation. How such solutions can be obtained, for example, by solving a matrix Riemann-Hilbert problem and how the metric tensor of the associated spacetime can be evaluated is described in detail. In chapter 4 the asymptotic behaviour and the similarity structure of the general algebro-geometric solutions of the Ernst equation are described, and the relationship of such solutions to the perhaps more familiar multi-soliton solutions is discussed. The next three chapters are based upon the authors' own published research: in chapter 5 it is shown that a problem involving counter-rotating infinitely thin disks of matter can be solved in terms of genus two Riemann theta functions, while in chapter 6 the authors describe numerical methods that facilitate the construction of such solutions, and in chapter 7 three-dimensional graphs are displayed that depict all metrical fields of the associated spacetime

  2. Integrative Mixed Methods Data Analytic Strategies in Research on School Success in Challenging Circumstances

    Science.gov (United States)

    Jang, Eunice E.; McDougall, Douglas E.; Pollon, Dawn; Herbert, Monique; Russell, Pia

    2008-01-01

    There are both conceptual and practical challenges in dealing with data from mixed methods research studies. There is a need for discussion about various integrative strategies for mixed methods data analyses. This article illustrates integrative analytic strategies for a mixed methods study focusing on improving urban schools facing challenging…

  3. Method for constructing approximate analytic solutions of differential equations with a polynomial right-hand side

    Science.gov (United States)

    Afanas'ev, A. P.; Dzyuba, S. M.

    2015-10-01

    A method for constructing approximate analytic solutions of systems of ordinary differential equations with a polynomial right-hand side is proposed. The implementation of the method is based on the Picard method of successive approximations and a procedure of continuation of local solutions. As an application, the problem of constructing the minimal sets of the Lorenz system is considered.

  4. 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.

  5. Waste Tank Organic Safety Program: Analytical methods development. Progress report, FY 1994

    International Nuclear Information System (INIS)

    The objectives of this task are to develop and document extraction and analysis methods for organics in waste tanks, and to extend these methods to the analysis of actual core samples to support the Waste Tank organic Safety Program. This report documents progress at Pacific Northwest Laboratory (a) during FY 1994 on methods development, the analysis of waste from Tank 241-C-103 (Tank C-103) and T-111, and the transfer of documented, developed analytical methods to personnel in the Analytical Chemistry Laboratory (ACL) and 222-S laboratory. This report is intended as an annual report, not a completed work

  6. Recent developments in radio-analytic methods for radiation protection. A resume

    International Nuclear Information System (INIS)

    The review covers recent developments in radio-analytic methods for radiation protection. Te validation and verification of radio-analytic methodologies for radionuclide determination in a variety of matrices is related to the appropriate sample preparation. Modern techniques are described from rotation evaporators, microwave systems to automated separation columns. New testing technologies allow the extension of detectable radionuclides and to reduce the detection limit significantly. These techniques are of importance for incorporation surveillance purposes but also for emergency management in case of radiation accidents. The modern radio-analytical techniques allow a sophisticated quality assurance in the frame of international cooperation and projects. A specific contribution covers the capability of alpha spectrometry.

  7. Analytical chemistry in semiconductor manufacturing: Techniques, role of nuclear methods and need for quality control

    International Nuclear Information System (INIS)

    This report is the result of a consultants meeting held in Gaithersburg, USA, 2-3 October 1987. The meeting was hosted by the National Bureau of Standards and Technology, and it was attended by 18 participants from Denmark, Finland, India, Japan, Norway, People's Republic of China and the USA. The purpose of the meeting was to assess the present status of analytical chemistry in semiconductor manufacturing, the role of nuclear analytical methods and the need for internationally organized quality control of the chemical analysis. The report contains the three presentations in full and a summary report of the discussions. Thus, it gives an overview of the need of analytical chemistry in manufacturing of silicon based devices, the use of nuclear analytical methods, and discusses the need for quality control. Refs, figs and tabs

  8. Development and Validation of HPLC Methods for Analytical and Preparative Purposes

    OpenAIRE

    Lindholm, Johan

    2004-01-01

    This thesis concerns the development and validation of high performance liquid chromatography (HPLC) methods aimed for two industrially important areas: (i) analysis of biotechnological synthesis and (ii) determination of adsorption isotherm parameters. There is today a lack of detailed recommendations for analytical procedures in the field of biotechnological production of drugs. Therefore, guidelines were given for analytical development and validation in this field; the production of 9α-hy...

  9. Development of novel analytical methods to study the metabolism of coumarin

    OpenAIRE

    Deasy, Brian

    1996-01-01

    The research in this thesis revolves around developing analytical methods for the determination of coumann and 7-hydroxycoumann for various applications. The techniques used in this work were, capillary electrophoresis, immunosensing and electrochemistry. Chapter 1 serves as general review of the analysis of coumann and 7-hydroxycoumann, including the many different types of analytical technique which have been used to analyse this drug. Capillary electrophoresis was used as the basis of a me...

  10. Application of Statistical Methods to Activation Analytical Results near the Limit of Detection

    DEFF Research Database (Denmark)

    Heydorn, Kaj; Wanscher, B.

    1978-01-01

    Reporting actual numbers instead of upper limits for analytical results at or below the detection limit may produce reliable data when these numbers are subjected to appropriate statistical processing. Particularly in radiometric methods, such as activation analysis, where individual standard...... deviations of analytical results may be estimated, improved discrimination may be based on the Analysis of Precision. Actual experimental results from a study of the concentrations of arsenic in human skin demonstrate the power of this principle....

  11. LC-MS/MS multi-analyte method for mycotoxin determination in food supplements

    OpenAIRE

    Diana Di Mavungu, José; Monbaliu, Sofie; Scippo, Marie-Louise; Maghuin-Rogister, Guy; Schneider, Yves-Jacques; Larondelle, Yvan; Callebaut, Alfons; Robbens, Johan; Van Peteghem, Carlos; De Saeger, Sarah

    2009-01-01

    Abstract A multi-analyte method for the liquid chromatography-tandem mass spectrometric determination of mycotoxins in food supplements is presented. The analytes included A and B trichothecenes (nivalenol, deoxynivalenol, 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol, neosolaniol, fusarenon-X, diacetoxyscirpenol, HT-2 toxin and T-2 toxin), aflatoxins (aflatoxin-B1, aflatoxin-B2, aflatoxin-G1 and aflatoxin-G2), Alternaria toxins (alternariol, alternariol methyl ether and altenuen...

  12. 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

  13. Assessment of Two Analytical Methods in Solving the Linear and Nonlinear Elastic Beam Deformation Problems

    DEFF Research Database (Denmark)

    Barari, Amin; Ganjavi, B.; Jeloudar, M. Ghanbari;

    2010-01-01

    Purpose – In the last two decades with the rapid development of nonlinear science, there has appeared ever-increasing interest of scientists and engineers in the analytical techniques for nonlinear problems. This paper considers linear and nonlinear systems that are not only regarded as general...... boundary value problems, but also are used as mathematical models in viscoelastic and inelastic flows. The purpose of this paper is to present the application of the homotopy-perturbation method (HPM) and variational iteration method (VIM) to solve some boundary value problems in structural engineering...... and fluid mechanics. Design/methodology/approach – Two new but powerful analytical methods, namely, He's VIM and HPM, are introduced to solve some boundary value problems in structural engineering and fluid mechanics. Findings – Analytical solutions often fit under classical perturbation methods. However...

  14. Analytical methods for vancomycin determination in biological fluids and in pharmaceuticals

    Directory of Open Access Journals (Sweden)

    Marta Maria Duarte Carvalho Vila

    2007-04-01

    Full Text Available Vancomycin is a glycopeptide antibiotic employed in the treatment of infections caused by certain methicillin-resistant staphylococci. It is indicated also for patients allergic to penicillin or when there is no response to penicillins or cephalosporins. The adequate vancomycin concentration levels in blood serum lies between 5 and 10 mg/L. Higher values are toxic, causing mainly nephrotoxicity and ototoxicity. Various analytical methods are described in the literature: spectrophotometric, immunologic, biologic and chromatographic methods. This paper reviews the main analytical methods for vancomycin determination in biological fluids and in pharmaceutical preparations.

  15. OPTIMAL METHOD FOR PREPARATION OF SILICATE ROCK SAMPLES FOR ANALYTICAL PURPOSES

    Directory of Open Access Journals (Sweden)

    Maja Vrkljan

    2004-12-01

    Full Text Available The purpose of this study was to determine an optimal dissolution method for silicate rock samples for further analytical purposes. Analytical FAAS method of determining cobalt, chromium, copper, nickel, lead and zinc content in gabbro sample and geochemical standard AGV-1 has been applied for verification. Dissolution in mixtures of various inorganic acids has been tested, as well as Na2CO3 fusion technique. The results obtained by different methods have been compared and dissolution in the mixture of HNO3 + HF has been recommended as optimal.

  16. Approximate Analytic and Numerical Solutions to Lane-Emden Equation via Fuzzy Modeling Method

    Directory of Open Access Journals (Sweden)

    De-Gang Wang

    2012-01-01

    Full Text Available A novel algorithm, called variable weight fuzzy marginal linearization (VWFML method, is proposed. This method can supply approximate analytic and numerical solutions to Lane-Emden equations. And it is easy to be implemented and extended for solving other nonlinear differential equations. Numerical examples are included to demonstrate the validity and applicability of the developed technique.

  17. Flammable gas safety program. Analytical methods development: FY 1994 progress report

    International Nuclear Information System (INIS)

    This report describes the status of developing analytical methods to account for the organic components in Hanford waste tanks, with particular focus on tanks assigned to the Flammable Gas Watch List. The methods that have been developed are illustrated by their application to samples obtained from Tank 241-SY-101 (Tank 101-SY)

  18. Application of the analytic hierarchy process method in the selection of optimal tactical radio communication systems

    Directory of Open Access Journals (Sweden)

    Saša M. Devetak

    2011-07-01

    Full Text Available This article deals with the analytic hierarchy process method in selecting an optimal tactic radio communication system. The problem has been defined, followed by the description of the AHP method procedure as well as the criteria and alternatives for radio communication systems. The problem was solved using the mathematical model and the presented software.

  19. Application of the analytic hierarchy process method in the selection of optimal tactical radio communication systems

    OpenAIRE

    Saša M. Devetak; Miroslav R. Terzić

    2011-01-01

    This article deals with the analytic hierarchy process method in selecting an optimal tactic radio communication system. The problem has been defined, followed by the description of the AHP method procedure as well as the criteria and alternatives for radio communication systems. The problem was solved using the mathematical model and the presented software.

  20. Development of analytical methods for the separation of plutonium, americium, curium and neptunium from environmental samples

    OpenAIRE

    Salminen, Susanna

    2009-01-01

    In this work, separation methods have been developed for the analysis of anthropogenic transuranium elements plutonium, americium, curium and neptunium from environmental samples contaminated by global nuclear weapons testing and the Chernobyl accident. The analytical methods utilized in this study are based on extraction chromatography. Highly varying atmospheric plutonium isotope concentrations and activity ratios were found at both Kurchatov (Kazakhstan), near the former Semipalatinsk...

  1. The nuclear analytical method in historical science: the case of precious metals from the new world

    International Nuclear Information System (INIS)

    The power of the nuclear analytical method using a cyclotron to solve the economic problems of contempory history is demonstrated with two examples. This method allows, for the first time, to estimate the percentage and therefore the true contribution of American silver and gold to European monetary and economic growth in the 16th early 17th and in the 18th century

  2. Analytical method for high resolution liquid chromatography for quality control French Macaw

    International Nuclear Information System (INIS)

    Was developed and validated an analytical method for high resolution liquid chromatography applicable to quality control of drugs dry French Macaw (Senna alata L. Roxb.) With ultraviolet detection at 340 nm. The method for high resolution liquid chromatography used to quantify the sennosides A and B, main components, was validated and proved to be specific, linear, precise and accurate. (Author)

  3. An analytical nodal method for time-dependent one-dimensional discrete ordinates problems

    International Nuclear Information System (INIS)

    In recent years, relatively little work has been done in developing time-dependent discrete ordinates (SN) computer codes. Therefore, the topic of time integration methods certainly deserves further attention. In this paper, we describe a new coarse-mesh method for time-dependent monoenergetic SN transport problesm in slab geometry. This numerical method preserves the analytic solution of the transverse-integrated SN nodal equations by constants, so we call our method the analytical constant nodal (ACN) method. For time-independent SN problems in finite slab geometry and for time-dependent infinite-medium SN problems, the ACN method generates numerical solutions that are completely free of truncation errors. Bsed on this positive feature, we expect the ACN method to be more accurate than conventional numerical methods for SN transport calculations on coarse space-time grids

  4. System and Method for Providing a Climate Data Analytic Services Application Programming Interface Distribution Package

    Science.gov (United States)

    Schnase, John L. (Inventor); Duffy, Daniel Q. (Inventor); Tamkin, Glenn S. (Inventor)

    2016-01-01

    A system, method and computer-readable storage devices for providing a climate data analytic services application programming interface distribution package. The example system can provide various components. The system provides a climate data analytic services application programming interface library that enables software applications running on a client device to invoke the capabilities of a climate data analytic service. The system provides a command-line interface that provides a means of interacting with a climate data analytic service by issuing commands directly to the system's server interface. The system provides sample programs that call on the capabilities of the application programming interface library and can be used as templates for the construction of new client applications. The system can also provide test utilities, build utilities, service integration utilities, and documentation.

  5. Analytical studies on local damage to reinforced concrete structures under impact loading by discrete element method

    International Nuclear Information System (INIS)

    This paper proposes a new analytical approach for assessing local damage to reinforced concrete structures subjected to impact load, by applying the discrete element method (DEM). It first outlines the basis concept and analytical formulation of the DEM. Next, it discusses the results of simulation analyses of concrete material tests, uni-axial compression tests and tensile splitting tests conducted to determine appropriate analytical parameters such as material constants, failure criteria and strength increase factors depending on strain rate. Finally, the adaptability of the DEM to local damage to reinforced concrete structures impacted by rigid and deformable missiles is verified through simulation analyses of various types of impact tests. Furthermore, the various impact response characteristics and failure mechanisms, such as impact forces, penetration behavior, reduction in missile velocity and energy transfer process, which are difficult to obtain experimentally, are analytically evaluated by the DEM. (orig.)

  6. Analytical solution of population balance equation involving aggregation and breakage in terms of auxiliary equation method

    Indian Academy of Sciences (India)

    Zehra Pinar; Abhishek Dutta; Guido Bény; Turgut Öziş

    2015-01-01

    This paper presents an effective analytical simulation to solve population balance equation (PBE), involving particulate aggregation and breakage, by making use of appropriate solution(s) of associated complementary equation via auxiliary equation method (AEM). Travelling wave solutions of the complementary equation of a nonlinear PBE with appropriately chosen parameters is taken to be analogous to the description of the dynamic behaviour of the particulate processes. For an initial proof-of-concept, a general case when the number of particles varies with respect to time is chosen. Three cases, i.e. (1) balanced aggregation and breakage, (2) when aggregation can dominate and (3) breakage can dominate, are selected and solved for their corresponding analytical solutions. The results are then compared with the available analytical solution, based on Laplace transform obtained from literature. In this communication, it is shown that the solution approach proposed via AEM is flexible and therefore more efficient than the analytical approach used in the literature.

  7. Analytical Method in Solving Flow of Viscoelastic Fluid in a Porous Converging Channel

    OpenAIRE

    M. Esmaeilpour; Naeem Roshan; Negar Roshan; D.D. Ganji

    2011-01-01

    An analytical method, called homotopy perturbation method (HPM), is used to compute an approximation to the solution of the nonlinear differential equation governing the problem of two-dimensional and steady flow of a second-grade fluid in a converging channel. The table and figures are presented for influencing various parameters on the velocity field. The results compare well with those obtained by the numerical method. The method is straightforward and concise, and it can also be applied t...

  8. Development and Validation of Analytical Method for Determination of Uranium Enrichment in Standard Nuclear Material

    International Nuclear Information System (INIS)

    A non-destructive analytical method has been developed for determination of uranium enrichment using hyper pure germanium (HPGe) gamma ray detector. The absolute efficiency was measured experimentally by different radioactive sources at different distances from the detector crystal. The variation of the absolute peak efficiency for 185.7 keV with source to detector distances has been determined and used to estimate the absolute peak efficiency for the nuclear material samples at 185 keV with the help of analytical method. The validity of the developed analytical method has been confirmed by measuring the 235U enrichment of uranium oxide powders (U3O8) contained in cylindrical aluminum cans

  9. Simplified Analytical Methods to Analyze Lock Gates Submitted to Ship Collisions and Earthquakes

    Directory of Open Access Journals (Sweden)

    Buldgen Loic

    2015-09-01

    Full Text Available This paper presents two simplified analytical methods to analyze lock gates submitted to two different accidental loads. The case of an impact involving a vessel is first investigated. In this situation, the resistance of the struck gate is evaluated by assuming a local and a global deforming mode. The super-element method is used in the first case, while an equivalent beam model is simultaneously introduced to capture the overall bending motion of the structure. The second accidental load considered in this paper is the seismic action, for which an analytical method is presented to evaluate the total hydrodynamic pressure applied on a lock gate during an earthquake, due account being taken of the fluid-structure interaction. For each of these two actions, numerical validations are presented and the analytical results are compared to finite-element solutions.

  10. Analysis profile of the fully grouted rock bolt in jointed rock using analytical and numerical methods

    Institute of Scientific and Technical Information of China (English)

    Ghadimi Mostafa; Shahriar Kourosh; Jalalifar Hossein

    2014-01-01

    The purpose of this study was to investigate the effect of bolt profile on load transfer mechanism of fully grouted bolts in jointed rocks using analytical and numerical methods. Based on the analytical method with development of methods, a new model is presented. To validate the analytical model, five different profiles modeled by ANSYS software. The profile of rock bolts T3 and T4 with load transfer capacity, respectively 180 and 195 kN in the jointed rocks was selected as the optimum profiles. Finally, the selected profiles were examined in Tabas Coal Mine. FLAC analysis indicates that patterns 6+7 with 2NO flexi bolt 4 m better than other patterns within the faulted zone.

  11. Development of CAD implementing the algorithm of boundary elements’ numerical analytical method

    Directory of Open Access Journals (Sweden)

    Yulia V. Korniyenko

    2015-03-01

    Full Text Available Up to recent days the algorithms for numerical-analytical boundary elements method had been implemented with programs written in MATLAB environment language. Each program had a local character, i.e. used to solve a particular problem: calculation of beam, frame, arch, etc. Constructing matrices in these programs was carried out “manually” therefore being time-consuming. The research was purposed onto a reasoned choice of programming language for new CAD development, allows to implement algorithm of numerical analytical boundary elements method and to create visualization tools for initial objects and calculation results. Research conducted shows that among wide variety of programming languages the most efficient one for CAD development, employing the numerical analytical boundary elements method algorithm, is the Java language. This language provides tools not only for development of calculating CAD part, but also to build the graphic interface for geometrical models construction and calculated results interpretation.

  12. 2D Stabilised analytic signal method in DC pole-pole potential data interpretation

    Indian Academy of Sciences (India)

    Paras R Pujari; Rambhatla G Sastry

    2003-03-01

    Using analytic signal method, interpretation of pole-pole secondary electric potentials due to 2D conductive/resistive prisms is presented. The estimated parameters are the location, lateral extent or width and depth to top surface of the prism. Forward modelling is attempted by 2D-Finite Difference method. The proposed stabilised analytic signal algorithm (RES2AS) uses Tikhonov's regularization scheme and FFT routines. The algorithm is tested on three theoretical examples and field data from the campus of Roorkee University. The stability of RES2AS is also tested on synthetic error prone secondary pole-pole potential data.

  13. Possibilities of Utilizing the Method of Analytical Hierarchy Process Within the Strategy of Corporate Social Business

    Science.gov (United States)

    Drieniková, Katarína; Hrdinová, Gabriela; Naňo, Tomáš; Sakál, Peter

    2010-01-01

    The paper deals with the analysis of the theory of corporate social responsibility, risk management and the exact method of analytic hierarchic process that is used in the decision-making processes. The Chapters 2 and 3 focus on presentation of the experience with the application of the method in formulating the stakeholders' strategic goals within the Corporate Social Responsibility (CSR) and simultaneously its utilization in minimizing the environmental risks. The major benefit of this paper is the application of Analytical Hierarchy Process (AHP).

  14. Advantages of Analytical Transformations in Monte Carlo Methods for Radiation Transport

    International Nuclear Information System (INIS)

    Monte Carlo methods for radiation transport typically attempt to solve an integral by directly sampling analog or weighted particles, which are treated as physical entities. Improvements to the methods involve better sampling, probability games or physical intuition about the problem. We show that significant improvements can be achieved by recasting the equations with an analytical transform to solve for new, non-physical entities or fields. This paper looks at one such transform, the difference formulation for thermal photon transport, showing a significant advantage for Monte Carlo solution of the equations for time dependent transport. Other related areas are discussed that may also realize significant benefits from similar analytical transformations

  15. Verification of an Analytical Method for Measuring Crystal Nucleation Rates in Glasses from DTA Data

    Science.gov (United States)

    Ranasinghe, K. S.; Wei, P. F.; Kelton, K. F.; Ray, C. S.; Day, D. E.

    2004-01-01

    A recently proposed analytical (DTA) method for estimating the nucleation rates in glasses has been evaluated by comparing experimental data with numerically computed nucleation rates for a model lithium disilicate glass. The time and temperature dependent nucleation rates were predicted using the model and compared with those values from an analysis of numerically calculated DTA curves. The validity of the numerical approach was demonstrated earlier by a comparison with experimental data. The excellent agreement between the nucleation rates from the model calculations and fiom the computer generated DTA data demonstrates the validity of the proposed analytical DTA method.

  16. [Behavioral therapy, cognitive behavioral therapy and cognitive-analytic methods in treatment of anorexia].

    Science.gov (United States)

    Schmidt, U

    1997-01-01

    This paper describes the current state of behavioural, cognitive-behavioural and cognitive-analytical treatments of anorexia nervosa and the underlying theoretical models. Purely behavioural treatment methods have been evaluated in a number of single case studies. Although effective in terms of increasing body weight, these methods are obsolete in view of their unpleasant side-effects. Cognitive-behavioural and cognitive-analytical therapies are much more appropriate for these patients given their complex symptomatology and frequently ambivalent attitude to treatment. However, so far evaluations of these treatments are rare. The reasons for this are discussed. PMID:9411461

  17. Analytical methods for determination of selected principal organic hazardous constituents in combustion products

    Energy Technology Data Exchange (ETDEWEB)

    Adams, R.E.; James, R.H.; Farr, L.B.; Thomason, M.M.; Miller, H.C.

    1986-01-01

    The paper gives an overview of generalized analytical procedures for determining designated principal organic hazardous constituents (POHCs) in combustion products; it also gives some examples of the techniques used for compounds such as 2,3,7,8-tetrachlorodibenzodioxin, selenourea, and several organo-arsenicals. Emissions from hazardous-waste combustion must be monitored to determine the destruction removal efficiency (DRE) for each designated POHC. Analytical methods for more than 150 POHCs were reviewed. A generalized HRGC/LRMS method to determine volatile, thermally stable POHCs was developed. A method based on HPLC with UV detection was also developed to provide an alternative for determining nonvolatile or thermally labile compounds. The generalized methods are applicable to many compounds, but specific POHCs may require variations in GC/MS or HPLC procedures. Inclusion in the paper does not mean that the sampling or analysis method is an official EPA method.

  18. Comparison of statistical validation parameters for three analytical methods for determination of total uranium fluorometric

    International Nuclear Information System (INIS)

    Three analytical methods for determination of uranium in environmental samples by fluorescent technique have been compared. The first method depends on uranium purification from iron using the mercury anode technique, while, in the second method, uranium was purified from iron using the ion exchange technique (Dowex 1x4), employing a solution of hydrochloric acid (4.5 mol l-1), ascorbic acid (7%) and hydrazine hydrate (1.8%). The third method was performed using the ion exchange technique followed by uranium elution using a diluted sulfuric acid. The results have showed that the third method was the best among the studied methods. This is due to better values for detection limits, repeatability, replicability and recovery coefficient, in addition to low quantities of consumed chemical materials and less analytical time being required. (author)

  19. Analytical numerical methods applied to linear discontinuous angular approximations of the transport equation in slab geometry

    International Nuclear Information System (INIS)

    In this paper we describe two analytical numerical methods applied to one-speed slab-geometry deep penetration transport problems. The linear discontinuous (LDN) equations are used to approximate the monoenergetic Boltzmann equation in slab geometry; they are obtained by considering a linear expansion of the angular flux inside each of the N elements of a uniform angular grid. The two analytical numerical methods are referred to as the spectral Green's function (SGF) nodal method and the Laplace transform (LTLDN) method. The SGF nodal method and the LTLDN method generate numerical solutions to the LDN equations that are completely free of spatial approximations, apart from finite arithmetic considerations. Numerical results to typical model problems and suggestions for future work are also presented. (orig.)

  20. Research on the simultaneous multi-components analytical method for polluted soil

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Kang Sup; Song, Duk Young; Choi, Byung In; Kim, Kun Han; Eum, Chul Hun; Jeon, Chi Wan; Lee, Jung Hwa [Korea Institute of Geology Mining and Materials, Taejon (Korea)

    1998-12-01

    Dissolution properties for the several inorganic pollutants in soils have been studied and simultaneous multi-components analytical method has been established with using ICP/MS for 13 monitoring elements in order to protect water and soil environments. And addition, more effective new analytical methods have been studied for TPH(total petroleum hydrocarbon) and organophosphorus compounds in soils. Several inorganic pollutants were spiked to 3 kinds of fresh soils which were sand, clay, loam. The dissolution properties of the prepared samples were investigated under the various extracting conditions such as extracting time, acid concentration, particle size, etc. in order to take basic information about the process of extraction test and improvement of related analytical methods. As the results, dissolution properties were affected mainly by acid concentration in extraction procedure and mineral composition of soils. On the other hand, extracting time, sort of acids and particle size of soils has a little influence on the dissolution properties. Cd revealed very high dissolving efficiency and As was very low in whole extracting test. Current analytical methods for the determination of soils are based on the purge and trap for volatiles such as gasoline and solvent extraction for semivolatiles such as kerosene and diesel oils. These methods are not proper in cost and time. In addition to, there are potential for analyte contamination and some problems in pretreatment procedure. In this study , we have discussed simultaneous determination of TPH containing gasoline, kerosene, diesel oils and etc. And determination of Organophosphorus compounds in soils has studied. In this procedure, the application of ultrasonication methods and several extraction methods were compared. In the results of this study, we could take very low practical detection limit and good precision. Approved methods were suitable for the determination of oils and pesticides in soil at high and low

  1. Analytical calculation of spectral phase of grism pairs by the geometrical ray tracing method

    Science.gov (United States)

    Rahimi, L.; Askari, A. A.; Saghafifar, H.

    2016-07-01

    The most optimum operation of a grism pair is practically approachable when an analytical expression of its spectral phase is in hand. In this paper, we have employed the accurate geometrical ray tracing method to calculate the analytical phase shift of a grism pair, at transmission and reflection configurations. As shown by the results, for a great variety of complicated configurations, the spectral phase of a grism pair is in the same form of that of a prism pair. The only exception is when the light enters into and exits from different facets of a reflection grism. The analytical result has been used to calculate the second-order dispersions of several examples of grism pairs in various possible configurations. All results are in complete agreement with those from ray tracing method. The result of this work can be very helpful in the optimal design and application of grism pairs at various configurations.

  2. Comparative analysis of methods for real-time analytical control of chemotherapies preparations.

    Science.gov (United States)

    Bazin, Christophe; Cassard, Bruno; Caudron, Eric; Prognon, Patrice; Havard, Laurent

    2015-10-15

    Control of chemotherapies preparations are now an obligation in France, though analytical control is compulsory. Several methods are available and none of them is presumed as ideal. We wanted to compare them so as to determine which one could be the best choice. We compared non analytical (visual and video-assisted, gravimetric) and analytical (HPLC/FIA, UV/FT-IR, UV/Raman, Raman) methods thanks to our experience and a SWOT analysis. The results of the analysis show great differences between the techniques, but as expected none us them is without defects. However they can probably be used in synergy. Overall for the pharmacist willing to get involved, the implementation of the control for chemotherapies preparations must be widely anticipated, with the listing of every parameter, and remains according to us an analyst's job. PMID:26299761

  3. Design and structural verification of locomotive bogies using combined analytical and experimental methods

    Science.gov (United States)

    Manea, I.; Popa, G.; Girnita, I.; Prenta, G.

    2015-11-01

    The paper presents a practical methodology for design and structural verification of the locomotive bogie frames using a modern software package for design, structural verification and validation through combined, analytical and experimental methods. In the initial stage, the bogie geometry is imported from a CAD program into a finite element analysis program, such as Ansys. The analytical model validation is done by experimental modal analysis carried out on a finished bogie frame. The bogie frame own frequencies and own modes by both experimental and analytic methods are determined and the correlation analysis of the two types of models is performed. If the results are unsatisfactory, the structural optimization should be performed. If the results are satisfactory, the qualification procedures follow by static and fatigue tests carried out in a laboratory with international accreditation in the field. This paper presents an application made on bogie frames for the LEMA electric locomotive of 6000 kW.

  4. Comparison and validation of two analytical methods for measurement of urinary sucrose and fructose excretion

    OpenAIRE

    Song, Xiaoling; Navarro, Sandi L.; Diep, Pho; Thomas, Wendy K.; Razmpoosh, Elena C.; Schwarz, Yvonne; Wang, Ching-Yun; Kratz, Mario; Neuhouser, Marian L; Lampe, Johanna W.

    2013-01-01

    Urinary sugars excretion has been proposed as a potential biomarker for intake of sugars. In this study we compared two analytical methods [gas chromatography (GC) and enzymatic reactions – UV absorption] for quantifying urinary fructose and sucrose using 24-hour urine samples from a randomized cross-over controlled feeding study. All samples were successfully quantified by the GC method; however 21% and 1.9% of samples were below the detection limit of the enzymatic method for sucrose and fr...

  5. Modifications of spectrophotometric methods for antioxidative vitamins determination convenient in analytic practice

    OpenAIRE

    Maciej Rutkowski; Krzysztof Grzegorczyk

    2007-01-01

    Although there are numerous methods for quantitative determination of antioxidative vitamins: C, E, and A, there are no methods favourable for the broadly understood analytic practice – they have various faults and limitations or require expensive apparatus. Therefore, we have elaborated modifications of valuable spectrophotometric methods for determination each of those vitamins, which originally could not be applied for laboratory practice from various regards. They are based on: ...

  6. Analytical methods used at IPR (Instituto de Pesquisas Radioativas - Minas Gerais, Brazil)

    International Nuclear Information System (INIS)

    The analytical methods available at IPR (MG-Brazil) for the routine determination of uranium are described. These methods are: gravimetric analysis; fluorescence spectroscopy, voltametry, polarography, absorption spectroscopy, beta-and gamma-radiometric analysis, gamma spectroscopy, activation analysis, X-rays fluorescence analysis and delayed neutron analysis. Some additional methods for the study of mineral ores, such as X-rays diffractometry, emmission spectroscopy, thermal analysis, etc, are also discussed

  7. Analytical method for the K/Ca age determination of geological samples

    International Nuclear Information System (INIS)

    An analytical procedure for the K/Ca age determination of geological samples is described, the relevant equations are developed and two alternative analytical methods are discussed according to their precision. An important precondition for the feasibility of the K/Ca method is the measurement of precise Ca isotope ratios. The ratio 40Ca/42Ca is used to determine the relative radiogenic 40Ca portion, whereas the 42Ca/44Ca ratio is taken as an internal standard. K and Ca in minerals are determined by flame atomic emission spectrometry with an internal lithium standard and by isotope dilution mass spectrometry, respectively. The contamination problem during the reprocessing of the samples is discussed. The results achieved by dating a langbeinite and a microcline sample by the K/Ca method agree well with those achieved by other age determination methods. The standard deviation of the K/Ca method in analyzing several feldspars ranges from 1.8-7.6%. (orig.)

  8. Analytical method used for intermediate products in continuous distillation of furfural

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Z.L.; Jia, M.; Wang, L.J.; Deng, Y.X.

    1981-01-01

    During distillation of furfural, analysis of main components in the crude furfural condensate and intermediate products is very important. Since furfural and methylfurfural are homologous and both furfural and acetone contain a carbonyl group, components in the sample must be separated before analysis. An improved analytical method has been studied, the accuracy and precision of which would meet the requirement of industrial standards. The analytical procedure was provided as follows: to determine the furfural content with gravimetric method of barbituric acid; to determine the methanol content with dichromate method after precipitating furfural and acetone, and distilling the liquid for analysis; and to determine the methylfurfural content with bromide-bromate method, which can be used only in the sample containing higher content of methylfurfural. For the sample in low content, the gas-liquid chromatographic method can be used. 7 references.

  9. T-2 toxin, a trichothecene mycotoxin: Review of toxicity, metabolism, and analytical methods

    Science.gov (United States)

    This review focuses on the toxicity and metabolism of T-2 toxin and the analytical methods used for the determination of T-2 toxin. Among the naturally occurring trichothecenes in food and feed, T-2 toxin is a cytotoxic fungal secondary metabolite produced by various species of Fusarium. Following...

  10. A conjugate direction method for approximating the analytic center of a polytope

    OpenAIRE

    Megiddo Nimrod; Mizuno Shinji; Kojima Masakazu

    1998-01-01

    The analytic center of an -dimensional polytope with a nonempty interior is defined as the unique minimizer of the logarithmic potential function over . It is shown that one cycle of a conjugate direction method, applied to the potential function at any such that , generates a point such that .

  11. Materials of the Second Sumy-Cracow-Muenster Symposium on Nuclear Analytical Methods

    International Nuclear Information System (INIS)

    The applications of nuclear analytical methods in physico-chemical, biological and medical studies have been presented in large number of applications. Environmental, geological and biological materials have been analysed by means of neutron activation analysis, proton microprobe, x-ray diffraction, synchrotron radiation X-ray spectrum analysis, ESR and others

  12. Development and validation of analytical methods for monomeric and oligomeric migrants from nylon 12 packaging materials.

    NARCIS (Netherlands)

    Stoffers, N.H.; Brandl, F.; Linssen, J.P.H.; Franz, R.

    2003-01-01

    Analytical methods for the determination of laurolactam-the monomer of nylon 12-as well as the cyclic dimer and trimer were established. High performance liquid chromatography using ultraviolet (HPLC-UV) and mass spectrometric detection (HPLC-MS) were both found suitable to identify and quantify mon

  13. An exact analytical solution of pool swell dynamics during depressurization by the method of characteristics

    International Nuclear Information System (INIS)

    An exact analytical solution, based on the method of characteristics, has been obtained for the spatial and temporal variation of vapor volumetric (void) fraction in a depressurizing pool. Numerical evaluations have shown that the axial void profile is strongly dependent on the drift velocity formulation, and that wall heat flux plays only a minor role in the pool swell transient. (Auth.)

  14. Knowledge, Skills, and Abilities for Entry-Level Business Analytics Positions: A Multi-Method Study

    Science.gov (United States)

    Cegielski, Casey G.; Jones-Farmer, L. Allison

    2016-01-01

    It is impossible to deny the significant impact from the emergence of big data and business analytics on the fields of Information Technology, Quantitative Methods, and the Decision Sciences. Both industry and academia seek to hire talent in these areas with the hope of developing organizational competencies. This article describes a multi-method…

  15. The development of analytical system for tracer level elements using laser enhanced ionization method

    International Nuclear Information System (INIS)

    An analytical system based on the laser enhanced ionization method was assembled. The LEI signal of Manganese was measured utilizing a one-color two-photon scheme. The linear relation between element concentration and electric charge in the quantitative analysis was ensured even at ppb level. For matrix-free Manganese, the detection limit of this system was 0.01ppb. (author)

  16. MULTI-ANALYTE CHEMISTRY METHODS FOR PESTICIDES WHICH ARE ACETOLACTATE SYNTHASE (ALS) INHIBITORS IN SOIL

    Science.gov (United States)

    A joint EPA/state/industry working group has developed several multi-analyte methods to analyze soils for low ppb (parts per billion) levels of herbicides (such as sulfonylureas, imidazolinones, and sulfonamides) that are acetolactate synthase (ALS) inhibitors and may cause phyto...

  17. Aspects of investigating scrambling in the synthesis of porphyrins Different analytical methods

    DEFF Research Database (Denmark)

    Nielsen, C.B.; Krebs, Frederik C

    2005-01-01

    Herein, we discuss the analyses and quantification of the different components in porphyrin mixtures, prepared from p-anisaidehyde, p-tolualdehyde, and 5-(4-bromophenyl)-dipyrromethane with acid catalysis, using NMR and HPLC. The advantages and disadvantages of these analytical methods are emphas...

  18. Semi-Analytical Weight Estimation Method for Fuselages with Oval Cross-Section

    NARCIS (Netherlands)

    Vos, R.; Hoogreef, M.F.M.

    2013-01-01

    This paper presents a semi-analytical method for the weight estimation of fuselages with an oval cross-section, applied to blended wing body aircraft. The weight estimation of the fuselage primary structure is based on a structural analysis of two-dimensional crosssections and it is completed by a s

  19. Analytical Quality by Design Approach in RP-HPLC Method Development for the Assay of Etofenamate in Dosage Forms

    OpenAIRE

    Peraman, R.; Bhadraya, K.; Reddy, Y. Padmanabha; Reddy, C. Surayaprakash; Lokesh, T.

    2015-01-01

    By considering the current regulatory requirement for an analytical method development, a reversed phase high performance liquid chromatographic method for routine analysis of etofenamate in dosage form has been optimized using analytical quality by design approach. Unlike routine approach, the present study was initiated with understanding of quality target product profile, analytical target profile and risk assessment for method variables that affect the method response. A liquid chromatogr...

  20. Vertical equilibrium with sub-scale analytical methods for geological CO2 sequestration

    KAUST Repository

    Gasda, S. E.

    2009-04-23

    Large-scale implementation of geological CO2 sequestration requires quantification of risk and leakage potential. One potentially important leakage pathway for the injected CO2 involves existing oil and gas wells. Wells are particularly important in North America, where more than a century of drilling has created millions of oil and gas wells. Models of CO 2 injection and leakage will involve large uncertainties in parameters associated with wells, and therefore a probabilistic framework is required. These models must be able to capture both the large-scale CO 2 plume associated with the injection and the small-scale leakage problem associated with localized flow along wells. Within a typical simulation domain, many hundreds of wells may exist. One effective modeling strategy combines both numerical and analytical models with a specific set of simplifying assumptions to produce an efficient numerical-analytical hybrid model. The model solves a set of governing equations derived by vertical averaging with assumptions of a macroscopic sharp interface and vertical equilibrium. These equations are solved numerically on a relatively coarse grid, with an analytical model embedded to solve for wellbore flow occurring at the sub-gridblock scale. This vertical equilibrium with sub-scale analytical method (VESA) combines the flexibility of a numerical method, allowing for heterogeneous and geologically complex systems, with the efficiency and accuracy of an analytical method, thereby eliminating expensive grid refinement for sub-scale features. Through a series of benchmark problems, we show that VESA compares well with traditional numerical simulations and to a semi-analytical model which applies to appropriately simple systems. We believe that the VESA model provides the necessary accuracy and efficiency for applications of risk analysis in many CO2 sequestration problems. © 2009 Springer Science+Business Media B.V.

  1. Effective Permeability of Fractured Rocks by Analytical Methods: A 3D Computational Study

    Science.gov (United States)

    Sævik, P. N.; Berre, I.; Jakobsen, M.; Lien, M.

    2013-12-01

    Analytical upscaling methods have been proposed in the literature to predict the effective hydraulic permeability of a fractured rock from its micro-scale parameters (fracture aperture, fracture orientation, fracture content, etc.). In this presentation, we put special emphasis on three effective medium methods (the symmetric and asymmetric self-consistent methods, and the differential method), and evaluate their accuracy for a wide range of parameter values. The analytical predictions are computed using our recently developed effective medium formulations, which are specifically adapted for fractured media. Compared to previous formulations, the new expressions have improved numerical stability properties, and require fewer input parameters. To assess their accuracy, the analytical predictions have been compared with 3D finite element simulations. Specifically, we generated realizations of several different fracture geometries, each consisting of 102 fractures within a unit cube. We applied unit potential difference on two opposing sides, and no-flux conditions on the remaining sides. A commercial finite-element solver was used to calculate the mean flux, from which the effective conductivity was found. This process was repeated for fracture densities up to ɛ = 1.0. Also, a wide range of fracture permeabilities was considered, from completely blocking to infinitely permeable fractures. The results were used to determine the range of applicability for each analytical method, which excels in different regions of the parameter space. For blocking fractures, the differential method is very accurate throughout the investigated parameter range. The symmetric self-consistent method also agrees well with the numerical results on sealed fractures, while the asymmetric self-consistent method is more unreliable. For permeable fractures, the performance of the methods depends on the dimensionless quantity λ = (Kfrac a)/(r Kmat ), describing the contrast between fracture and

  2. Analytical method for internal dose determination caused by chronically radionuclides inhalation to respiration system

    International Nuclear Information System (INIS)

    Analytical method for internal dose determination caused by chronically radionuclides inhalation to respiratory system with the constant rate of radionuclide concentration inhaled has been developed. The dose calculation is solved solved analytically using distribution and accumulation of radionuklida model in respiratory system. A computer program was then made to calculate internal dose in respiratory system easily and quickly. Computer program is arranged using Borland C++ 4.5 language. The value of internal dose on time t after inhalation depend on the radionuclides, the half time ,radionuclides AMAD, radionuclides class, radiation type, energy absorbed by respiratory organ, organ mass, the radionuclides concentration inhaled, the inhalation period

  3. Validation of analytical methods for food control. Report of a Joint FAO/IAEA expert consultation

    International Nuclear Information System (INIS)

    There is a continuing need for reliable analytical methods for use in determining compliance with national regulations as well as international requirements in all areas of food quality and safety. The reliability of a method is determined by some form of a validation procedure. The Codex Alimentarius Commission (CAC), for example, requires that in order for a method of analysis to be included in a Codex commodity standard, certain method performance information should be available. This includes specificity, accuracy, precision (repeatability, reproducibility), limit of detection, sensitivity, applicability and practicability, as appropriate. This very often requires an extensive collaborative study be undertaken to obtain the necessary data. Methods which have successfully undergone this performance review testing have been considered to be validated for purposes of analyses under Codex commodity standards. Within this environment, the entire area of validation of analytical methods used in food control for Codex purposes has been discussed at length by the CCMAS, as well as the CCRVDF and the Codex Committee on Pesticide Residues (CCPR). All three Committees supported the holding of a consultation to provide expert advice and guidance in this area. The present Joint FAO/lAEA Consultation on Validation of Analytical Methods for Food Control was convened for that purpose

  4. A simple analytical method for residual stress measurement on suspended MEM structures using surface profilometry

    International Nuclear Information System (INIS)

    This paper presents an analytical method to calculate residual stress and Young's modulus in clamped–clamped beams. These types of structures are a typical building block of many MEMS devices, and this guarantees accurate transferability of the measured parameters. The method is based on the determination of beam bending as a function of applied load by means of a surface profiler, and as a function of beam length. By modeling analytically both the elastic and the stress contribution to beam bending, it is possible to obtain both the stress value and Young's modulus by a simple fitting of the experimental data. Results are presented for electrodeposited gold beam arrays of different widths, but the method is in principle exploitable for every type of suspended film where the residual stress strongly influences the material properties. Accuracy and limitations of the method are also discussed. (paper)

  5. Analytical synthetic methods of solution of neutron transport equation with diffusion theory approaches energy multigroup

    International Nuclear Information System (INIS)

    In this work we developed a software to model and generate results in tables and graphs of one-dimensional neutron transport problems in multi-group formulation of energy. The numerical method we use to solve the problem of neutron diffusion is analytic, thus eliminating the truncation errors that appear in classical numerical methods, e.g., the method of finite differences. This numerical analytical method increases the computational efficiency, since they are not refined spatial discretization necessary because for any spatial discretization grids used, the numerical result generated for the same point of the domain remains unchanged unless the rounding errors of computational finite arithmetic. We chose to develop a computational application in MatLab platform for numerical computation and program interface is simple and easy with knobs. We consider important to model this neutron transport problem with a fixed source in the context of shielding calculations of radiation that protects the biosphere, and could be sensitive to ionizing radiation

  6. Analytical method for analyzing c-channel stiffener made of laminate composite

    Science.gov (United States)

    Kumton, Tattchapong

    Composite materials play the important role in the aviation industry. Conventional materials such as aluminum were replaced by composite material on the main structures. The objective of this study focuses on development of analytical method to analyze the laminated composite structure with C-channel cross-section. A lamination theory base closed-form solution was developed to analysis ply stresses on the C-channel cross-section. The developed method contains the effects of coupling due to unsymmetrical of both laminate and structural configuration levels. The present method also included the expression of the sectional properties such as centroid, axial and bending stiffnesses of cross-section. The results obtain from analytical method showed an excellent agreement with finite element results.

  7. In-depth assessment of analytical methods for olive oil purity, safety, and quality characterization.

    Science.gov (United States)

    Tena, Noelia; Wang, Selina C; Aparicio-Ruiz, Ramón; García-González, Diego L; Aparicio, Ramón

    2015-05-13

    This paper evaluates the performance of the current analytical methods (standard and widely used otherwise) that are used in olive oil for determining fatty acids, triacylglycerols, mono- and diacylglycerols, waxes, sterols, alkyl esters, erythrodiol and uvaol, tocopherols, pigments, volatiles, and phenols. Other indices that are commonly used, such as free acidity and peroxide value, are also discussed in relation to their actual utility in assessing quality and safety and their possible alternatives. The methods have been grouped on the basis of their applications: (i) purity and authenticity; (ii) sensory quality control; and (iii) unifying methods for different applications. The speed of the analysis, advantages and disadvantages, and multiple quality parameters are assessed. Sample pretreatment, physicochemical and data analysis, and evaluation of the results have been taken into consideration. Solutions based on new chromatographic methods or spectroscopic analysis and their analytical characteristics are also presented. PMID:25891853

  8. A simple analytical method for heterogeneity corrections in low dose rate prostate brachytherapy

    Science.gov (United States)

    Hueso-González, Fernando; Vijande, Javier; Ballester, Facundo; Perez-Calatayud, Jose; Siebert, Frank-André

    2015-07-01

    In low energy brachytherapy, the presence of tissue heterogeneities contributes significantly to the discrepancies observed between treatment plan and delivered dose. In this work, we present a simplified analytical dose calculation algorithm for heterogeneous tissue. We compare it with Monte Carlo computations and assess its suitability for integration in clinical treatment planning systems. The algorithm, named as RayStretch, is based on the classic equivalent path length method and TG-43 reference data. Analytical and Monte Carlo dose calculations using Penelope2008 are compared for a benchmark case: a prostate patient with calcifications. The results show a remarkable agreement between simulation and algorithm, the latter having, in addition, a high calculation speed. The proposed analytical model is compatible with clinical real-time treatment planning systems based on TG-43 consensus datasets for improving dose calculation and treatment quality in heterogeneous tissue. Moreover, the algorithm is applicable for any type of heterogeneities.

  9. Analytical method for estimating the thermal expansion coefficient of metals at high temperature

    International Nuclear Information System (INIS)

    In this paper, we propose an analytical method for estimating the thermal expansion coefficient (TEC) of metals at high-temperature ranges. Although the conventional method based on quasiharmonic approximation (QHA) shows good results at low temperatures, anharmonic effects caused by large-amplitude thermal vibrations reduces its accuracy at high temperatures. Molecular dynamics (MD) naturally includes the anharmonic effect. However, since the computational cost of MD is relatively high, in order to make an interatomic potential capable of reproducing TEC, an analytical method is essential. In our method, analytical formulation of the radial distribution function (RDF) at finite temperature realizes the estimation of the TEC. Each peak of the RDF is approximated by the Gaussian distribution. The average and variance of the Gaussian distribution are formulated by decomposing the fluctuation of interatomic distance into independent elastic waves. We incorporated two significant anharmonic effects into the method. One is the increase in the averaged interatomic distance caused by large amplitude vibration. The second is the variation in the frequency of elastic waves. As a result, the TECs of fcc and bcc crystals estimated by our method show good agreement with those of MD. Our method enables us to make an interatomic potential that reproduces the TEC at high temperature. We developed the GEAM potential for nickel. The TEC of the fitted potential showed good agreement with experimental data from room temperature to 1000 K. As compared with the original potential, it was found that the third derivative of the wide-range curve was modified, while the zeroth, first and second derivatives were unchanged. This result supports the conventional theory of solid state physics. We believe our analytical method and developed interatomic potential will contribute to future high-temperature material development. (paper)

  10. Analytical method for calculation of navigational data for the position of a satellite

    Science.gov (United States)

    Lala, P.

    1975-01-01

    A method is described for calculating the position of a satellite at the instants when measurements are made on board. The initial conditions used were the mean orbital elements of the satellite and their time derivatives in one orbit. The results of the calculation are compared with those obtained by numerical integration, and it is found that results are identical at the beginning of an orbit, but change as the orbit progresses. The advantages and disadvantages of the analytical method are presented.

  11. Analytical methods for drinking water; Metodi di analisi per le acque destinate al consumo umano

    Energy Technology Data Exchange (ETDEWEB)

    Ottaviani, Massimo; Bonadonna, Lucia [Istituto Superiore di Sanita`, Rome (Italy). Lab. di Igiene Ambientale

    1997-03-01

    These analytical methods for drinking water were elaborated by the second Sub-commission of the Permanent study committee ex-article 9 of Italian Ministerial Decree (DM) of March 26, 1991, established at the Ministry of Health. The methods concern the chemical and microbiological parameters included in the C1, C2 and C3 controls of the Annex II of the Decree of the President of the Republic (DPR) 236/88.

  12. Benchmarking the invariant embedding method against analytical solutions in model transport problems

    OpenAIRE

    Wahlberg Malin; Pázsit Imre

    2006-01-01

    The purpose of this paper is to demonstrate the use of the invariant embedding method in a few model transport problems for which it is also possible to obtain an analytical solution. The use of the method is demonstrated in three different areas. The first is the calculation of the energy spectrum of sputtered particles from a scattering medium without absorption, where the multiplication (particle cascade) is generated by recoil production. Both constant and energy dependent cross-sections ...

  13. Development of analytical methods for multiplex bio-assay with inductively coupled plasma mass spectrometry

    OpenAIRE

    Ornatsky, Olga I.; Kinach, Robert; Bandura, Dmitry R.; Lou, Xudong; Tanner, Scott D; Baranov, Vladimir I.; Nitz, Mark; Mitchell A. Winnik

    2008-01-01

    Advances in the development of highly multiplexed bio-analytical assays with inductively coupled plasma mass spectrometry (ICP-MS) detection are discussed. Use of novel reagents specifically designed for immunological methods utilizing elemental analysis is presented. The major steps of method development, including selection of elements for tags, validation of tagged reagents, and examples of multiplexed assays, are considered in detail. The paper further describes experimental protocols for...

  14. Analytical approach for Dirac equation using the saddle-point variational method

    International Nuclear Information System (INIS)

    A general analytical approximate method for Dirac equation with confining power-law scalar plus vector potentials is presented. The method consists in an improved version of a saddle-point variational approach and it is applied to the fundamental state of massless particles for some special cases of interest. Our treatment emphasizes aspects such as the quantum-mechanical relativistic Virial Theorem and the saddle-point character of the critical point of (H), the expectation value of the total energy. (author)

  15. Analytic Input to Societal Emergency Management - On the Design of Methods

    OpenAIRE

    Abrahamsson, Marcus

    2009-01-01

    Information from performed risk and vulnerability analyses, evaluation of responses in relation to actual emergencies etcetera can be very useful in efforts directed at preventing, mitigating and/or preparing for future emergencies. This thesis focuses on the development of methods for such analysis and evaluation. A general process for systematic design of methods is introduced and discussed and some of the main types of analytic input to societal emergency management are examined in terms o...

  16. International symposium on quality assurance for analytical methods in isotope hydrology. Book of extended synopses

    International Nuclear Information System (INIS)

    A large variety of isotopic techniques is available and commonly used in water resources investigations as well as in a wide range of other scientific fields. These techniques include the stable isotope analysis of light elements (H, C, N, O, S), activity measurements of radioactive isotopes at environmental level (3H, 14C, 3H/3He, 85Kr) as well as measurements of CFCs, SF6 and other chemical and isotopic tracers. They provide valuable tools for the assessment of scientific questions and the solution of practical problems. During the last decade, new analytical tools have significantly fostered the application of isotopic techniques in many new fields and caused a steep increase in the number of laboratories applying these methods. International trends in improved analytical quality and requirements for laboratory certification and accreditation have pushed issues of quality control and quality assurance to a high level of importance for the operation of isotope laboratories worldwide. The objectives of the symposium are to promote a wide exchange of information on key issues for high quality isotopic measurements. The main focus is on the analytical techniques and on all means to ensure high quality standards for isotopic measurements. Recent advances in analytical quality assurance and laboratory quality systems will be presented and discussed together with state-of-the-art techniques. The scope of the conference is to demonstrate the use of best laboratory practices in the following fields: calibration of measurements and traceability; interlaboratory comparisons; best laboratory practices for daily analyses of samples; quality control and statistical evaluation of results; calculation of uncertainty budgets; new analytical techniques; improvements in precision and accuracy of analytical methods; laboratory information management, databases and sample handling; laboratory quality systems and international guides. The 42 papers are indexed individually

  17. Analytical Method Validation of Gamma Spectrometric Procedure for the Determination of γ-Emitters in Environmental Samples

    International Nuclear Information System (INIS)

    It is internationally recognized that validation is necessary in analytical laboratories. The use of validated methods is important for an analytical laboratory to show its qualification and competency. This work describes the methods for validation of gamma spectrometric analytical procedure in the determination of some gamma emitters in environmental samples. The method was tested and validated in terms of repeatability, trueness, reproducibility in accordance with ISO guidelines using IAEA reference materials with different matrixes and compositions

  18. Trigonometric and hyperbolic functions method for constructing analytic solutions to nonlinear plane magnetohydrodynamics equilibrium equations

    Energy Technology Data Exchange (ETDEWEB)

    Moawad, S. M., E-mail: smmoawad@hotmail.com [Department of Mathematics, Faculty of Science, Beni-Suef University, Beni-Suef (Egypt)

    2015-02-15

    In this paper, we present a solution method for constructing exact analytic solutions to magnetohydrodynamics (MHD) equations. The method is constructed via all the trigonometric and hyperbolic functions. The method is applied to MHD equilibria with mass flow. Applications to a solar system concerned with the properties of coronal mass ejections that affect the heliosphere are presented. Some examples of the constructed solutions which describe magnetic structures of solar eruptions are investigated. Moreover, the constructed method can be applied to a variety classes of elliptic partial differential equations which arise in plasma physics.

  19. Trigonometric and hyperbolic functions method for constructing analytic solutions to nonlinear plane magnetohydrodynamics equilibrium equations

    Science.gov (United States)

    Moawad, S. M.

    2015-02-01

    In this paper, we present a solution method for constructing exact analytic solutions to magnetohydrodynamics (MHD) equations. The method is constructed via all the trigonometric and hyperbolic functions. The method is applied to MHD equilibria with mass flow. Applications to a solar system concerned with the properties of coronal mass ejections that affect the heliosphere are presented. Some examples of the constructed solutions which describe magnetic structures of solar eruptions are investigated. Moreover, the constructed method can be applied to a variety classes of elliptic partial differential equations which arise in plasma physics.

  20. Trigonometric and hyperbolic functions method for constructing analytic solutions to nonlinear plane magnetohydrodynamics equilibrium equations

    International Nuclear Information System (INIS)

    In this paper, we present a solution method for constructing exact analytic solutions to magnetohydrodynamics (MHD) equations. The method is constructed via all the trigonometric and hyperbolic functions. The method is applied to MHD equilibria with mass flow. Applications to a solar system concerned with the properties of coronal mass ejections that affect the heliosphere are presented. Some examples of the constructed solutions which describe magnetic structures of solar eruptions are investigated. Moreover, the constructed method can be applied to a variety classes of elliptic partial differential equations which arise in plasma physics