Revisiting factors controlling methane emissions from high-Arctic tundra

DEFF Research Database (Denmark)

Mastepanov, M.; Sigsgaard, C.; Tagesson, T.

2013-01-01

controlling methane emission, i.e. temperature and water table position. Late in the growing season CH4 emissions were found to be very similar between the study years (except the extremely dry 2010) despite large differences in climatic factors (temperature and water table). Late-season bursts of CH4...... short-term control factors (temperature and water table). Our findings suggest the importance of multiyear studies with a continued focus on shoulder seasons in Arctic ecosystems....

Analysis of Passenger Car Emission Factors in RDE Tests

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Pielecha Jacek

2016-01-01

Full Text Available The article presents a study on emission measurements in passenger cars in tests conducted under real traffic conditions – Real Driving Emissions using a Portable Emission Measurement System type of equipment. A special feature of the outlined RDE tests is that they were performed in Polish road conditions, and thus their parameters may differ from their counterparts adopted in most European Union countries. Based on the findings vehicle emission conformity factors were developed, characterized as the fractional increase (or decrease of traffic emissions during the homologation test or under normal operation conditions in relation to the emission limit standards (for chosen emission class of the vehicle. Conducted research and the calculated conformity factors allowed for the environmental impact assessment of the vehicles of various emission classes, while also allowing early actions to restrict the emissions of selected components in passenger vehicles. The methods and measures used can also be applied to other types of vehicles (e.g. heavy duty or off-road vehicles or vehicles powered by other fuels.

Revised emission factors for gas engines including start/stop emissions

Energy Technology Data Exchange (ETDEWEB)

Nielsen, Malene; Boll Illerup, J.; Birr-Petersen, K.

2008-06-15

Liberalisation of the electricity market has led to Danish gas engine plants increasingly converting to the spot and regulating power markets. In order to offer regulating power, plants need to be able to start and stop the engines at the plants quickly. The liberalisation causes a considerable change of operation practice of the engines e.g. less full load operation hours /year. The project provides an inventory determining the scale of the emissions during the start and stop sequence as well as proposals for engine modifications aimed at reducing start/stop emissions. This report includes calculation of emission factors as well as an inventory of total emissions and reduction potentials. (au)

Particle and VOC emission factor measurements for anthropogenic sources in West Africa

Directory of Open Access Journals (Sweden)

S. Keita

2018-06-01

Full Text Available A number of campaigns have been carried out to establish the emission factors of pollutants from fuel combustion in West Africa, as part of work package 2 (Air Pollution and Health of the DACCIWA (Dynamics-Aerosol-Chemistry-Cloud Interactions in West Africa FP7 program. Emission sources considered here include wood (hevea and iroko and charcoal burning, charcoal making, open trash burning, and vehicle emissions, including trucks, cars, buses and two-wheeled vehicles. Emission factors of total particulate matter (TPM, elemental carbon (EC, primary organic carbon (OC and volatile organic compounds (VOCs have been established. In addition, emission factor measurements were performed in combustion chambers in order to reproduce field burning conditions for a tropical hardwood (hevea, and obtain particulate emission factors by size (PM0.25, PM1, PM2.5 and PM10. Particle samples were collected on quartz fiber filters and analyzed using gravimetric method for TPM and thermal methods for EC and OC. The emission factors of 58 VOC species were determined using offline sampling on a sorbent tube. Emission factor results for two species of tropical hardwood burning of EC, OC and TPM are 0.98 ± 0.46 g kg−1 of fuel burned (g kg−1, 11.05 ± 4.55 and 41.12 ± 24.62 g kg−1, respectively. For traffic sources, the highest emission factors among particulate species are found for the two-wheeled vehicles with two-stroke engines (2.74 g kg−1 fuel for EC, 65.11 g kg−1 fuel for OC and 496 g kg−1 fuel for TPM. The largest VOC emissions are observed for two-stroke two-wheeled vehicles, which are up to 3 times higher than emissions from light-duty and heavy-duty vehicles. Isoprene and monoterpenes, which are usually associated with biogenic emissions, are present in almost all anthropogenic sources investigated during this work and could be as significant as aromatic emissions in wood burning (1 g kg−1 fuel. EC is

Development of cotton gin PM10 emission factors for EPA’s AP-42

Science.gov (United States)

The Compilation of Air Pollution Emission Factors (AP-42) emission factors are assigned ratings, from A (Excellent) to E (Poor), based on the quality of data used to develop them. All current PM10 cotton gin emission factors received quality ratings of D or lower. In an effort to improve these ratin...

Update on the development of cotton gin PM10 emission factors for EPA's AP-42

Science.gov (United States)

A cotton ginning industry-supported project was initiated in 2008 to update the U.S. Environmental Protection Agency’s (EPA) Compilation of Air Pollution Emission Factors (AP-42) to include PM10 emission factors. This study develops emission factors from the PM10 emission factor data collected from ...

Differentiation of nitrous oxide emission factors for agricultural soils

International Nuclear Information System (INIS)

Lesschen, Jan Peter; Velthof, Gerard L.; Vries, Wim de; Kros, Johannes

2011-01-01

Nitrous oxide (N 2 O) direct soil emissions from agriculture are often estimated using the default IPCC emission factor (EF) of 1%. However, a large variation in EFs exists due to differences in environment, crops and management. We developed an approach to determine N 2 O EFs that depend on N-input sources and environmental factors. The starting point of the method was a monitoring study in which an EF of 1% was found. The conditions of this experiment were set as the reference from which the effects of 16 sources of N input, three soil types, two land-use types and annual precipitation on the N 2 O EF were estimated. The derived EF inference scheme performed on average better than the default IPCC EF. The use of differentiated EFs, including different regional conditions, allows accounting for the effects of more mitigation measures and offers European countries a possibility to use a Tier 2 approach. - Highlights: → We developed an N 2 O emission factor inference scheme for agricultural soils. → This scheme accounts for different N-input sources and environmental conditions. → The derived EF inference scheme performed better than the default IPCC EF. → The use of differentiated EFs allows for better accounting of mitigation measures. - Emission factors for nitrous oxide from agricultural soils are derived as a function of N-input sources and environmental conditions on the basis of empirical information.

Factor Decomposition Analysis of Energy-Related CO2 Emissions in Tianjin, China

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Zhe Wang

2015-07-01

Full Text Available Tianjin is the largest coastal city in northern China with rapid economic development and urbanization. Energy-related CO2 emissions from Tianjin’s production and household sectors during 1995–2012 were calculated according to the default carbon-emission coefficients provided by the Intergovernmental Panel on Climate Change. We decomposed the changes in CO2 emissions resulting from 12 causal factors based on the method of Logarithmic Mean Divisia Index. The examined factors were divided into four types of effects: energy intensity effect, structure effect, activity intensity effect, scale effect and the various influencing factors imposed differential impacts on CO2 emissions. The decomposition outcomes indicate that per capita GDP and population scale are the dominant positive driving factors behind the growth in CO2 emissions for all sectors, while the energy intensity of the production sector is the main contributor to dampen the CO2 emissions increment, and the contributions from industry structure and energy structure need further enhancement. The analysis results reveal the reasons for CO2 emission changes in Tianjin and provide a solid basis upon which policy makers may propose emission reduction measures and approaches for the implementation of sustainable development strategies.

Pre-Harvest Sugarcane Burning: Determination of Emission Factors through Laboratory Measurements

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João Andrade Carvalho

2012-02-01

Full Text Available Sugarcane is an important crop for the Brazilian economy and roughly 50% of its production is used to produce ethanol. However, the common practice of pre-harvest burning of sugarcane straw emits particulate material, greenhouse gases, and tropospheric ozone precursors to the atmosphere. Even with policies to eliminate the practice of pre-harvest sugarcane burning in the near future, there is still significant environmental damage. Thus, the generation of reliable inventories of emissions due to this activity is crucial in order to assess their environmental impact. Nevertheless, the official Brazilian emissions inventory does not presently include the contribution from pre-harvest sugarcane burning. In this context, this work aims to determine sugarcane straw burning emission factors for some trace gases and particulate material smaller than 2.5 μm in the laboratory. Excess mixing ratios for CO2, CO, NOX, UHC (unburned hydrocarbons, and PM2.5 were measured, allowing the estimation of their respective emission factors. Average estimated values for emission factors (g kg−1 of burned dry biomass were 1,303 ± 218 for CO2, 65 ± 14 for CO, 1.5 ± 0.4 for NOX, 16 ± 6 for UHC, and 2.6 ± 1.6 for PM2.5. These emission factors can be used to generate more realistic emission inventories and therefore improve the results of air quality models.

Emission factors from residential combustion appliances burning Portuguese biomass fuels.

Science.gov (United States)

Fernandes, A P; Alves, C A; Gonçalves, C; Tarelho, L; Pio, C; Schimdl, C; Bauer, H

2011-11-01

Smoke from residential wood burning has been identified as a major contributor to air pollution, motivating detailed emission measurements under controlled conditions. A series of experiments were performed to compare the emission levels from two types of wood-stoves to those of fireplaces. Eight types of biomass were burned in the laboratory: wood from seven species of trees grown in the Portuguese forest (Pinus pinaster, Eucalyptus globulus, Quercus suber, Acacia longifolia, Quercus faginea, Olea europaea and Quercus ilex rotundifolia) and briquettes produced from forest biomass waste. Average emission factors were in the ranges 27.5-99.2 g CO kg(-1), 552-1660 g CO(2) kg(-1), 0.66-1.34 g NO kg(-1), and 0.82-4.94 g hydrocarbons kg(-1) of biomass burned (dry basis). Average particle emission factors varied between 1.12 and 20.06 g kg(-1) biomass burned (dry basis), with higher burn rates producing significantly less particle mass per kg wood burned than the low burn rates. Particle mass emission factors from wood-stoves were lower than those from the fireplace. The average emission factors for organic and elemental carbon were in the intervals 0.24-10.1 and 0.18-0.68 g kg(-1) biomass burned (dry basis), respectively. The elemental carbon content of particles emitted from the energy-efficient "chimney type" logwood stove was substantially higher than in the conventional cast iron stove and fireplace, whereas the opposite was observed for the organic carbon fraction. Pinus pinaster, the only softwood species among all, was the biofuel with the lowest emissions of particles, CO, NO and hydrocarbons.

Estimating end-use emissions factors for policy analysis: the case of space cooling and heating.

Science.gov (United States)

Jacobsen, Grant D

2014-06-17

This paper provides the first estimates of end-use specific emissions factors, which are estimates of the amount of a pollutant that is emitted when a unit of electricity is generated to meet demand from a specific end-use. In particular, this paper provides estimates of emissions factors for space cooling and heating, which are two of the most significant end-uses. The analysis is based on a novel two-stage regression framework that estimates emissions factors that are specific to cooling or heating by exploiting variation in cooling and heating demand induced by weather variation. Heating is associated with similar or greater CO2 emissions factor than cooling in all regions. The difference is greatest in the Midwest and Northeast, where the estimated CO2 emissions factor for heating is more than 20% larger than the emissions factor for cooling. The minor differences in emissions factors in other regions, combined with the substantial difference in the demand pattern for cooling and heating, suggests that the use of overall regional emissions factors is reasonable for policy evaluations in certain locations. Accurately quantifying the emissions factors associated with different end-uses across regions will aid in designing improved energy and environmental policies.

Emissions from laboratory combustion of wildland fuels: Emission factors and source profiles

Science.gov (United States)

L.-W. Anthony Chen; Hans Moosmuller; W. Patrick Arnott; Judith C. Chow; John G. Watson; Ronald A. Susott; Ronald E. Babbitt; Cyle E. Wold; Emily N. Lincoln; Wei Min Hao

2007-01-01

Combustion of wildland fuels represents a major source of particulate matter (PM) and light-absorbing elemental carbon (EC) on a national and global scale, but the emission factors and source profiles have not been well characterized with respect to different fuels and combustion phases. These uncertainties limit the accuracy of current emission inventories, smoke...

Time trend of polycyclic aromatic hydrocarbon emission factors from motor vehicles

Science.gov (United States)

Tao, Shu; Shen, Huizhong; Wang, Rong; Sun, Kang

2010-05-01

Motor vehicle is an important emission source of polycyclic aromatic hydrocarbons (PAHs) and this is particularly true in urban areas. Motor vehicle emission factors (EFs) for individual PAH compound reported in the literature varied for 4 to 5 orders of magnitude, leading to high uncertainty in emission estimation. In this study, the major factors affecting EFs were investigated and characterized by regression models. Based on the model developed, a motor vehicle PAH emission inventory at country level was developed. It was found that country and model year are the most important factors affecting EFs for PAHs. The influence of the two factors can be quantified by a single parameter of per capita gross domestic production (purchasing power parity), which was used as the independent variables of the regression models. The models developed using randomly selected 80% of measurements and tested with the remained data accounted for 28 to 48% of the variations in EFs for PAHs measured in 16 countries over 50 years. The regression coefficients of the EF prediction models were molecular weight dependent. Motor vehicle emission of PAHs from individual countries in the world in 1985, 1995, 2005, 2015, and 2025 were calculated and the global emission of total PAHs were 470, 390, and 430 Gg in 1985, 1995, and 2005 and will be 290 and 130 Gg in 2015 and 2025, respectively. The emission is currently passing its peak and will decrease due to significant decrease in China and other developing countries.

Determining size-specific emission factors for environmental tobacco smoke particles

Energy Technology Data Exchange (ETDEWEB)

Klepeis, Neil E.; Apte, Michael G.; Gundel, Lara A.; Sextro, Richard G.; Nazaroff, William W.

2002-07-07

Because size is a major controlling factor for indoor airborne particle behavior, human particle exposure assessments will benefit from improved knowledge of size-specific particle emissions. We report a method of inferring size-specific mass emission factors for indoor sources that makes use of an indoor aerosol dynamics model, measured particle concentration time series data, and an optimization routine. This approach provides--in addition to estimates of the emissions size distribution and integrated emission factors--estimates of deposition rate, an enhanced understanding of particle dynamics, and information about model performance. We applied the method to size-specific environmental tobacco smoke (ETS) particle concentrations measured every minute with an 8-channel optical particle counter (PMS-LASAIR; 0.1-2+ micrometer diameters) and every 10 or 30 min with a 34-channel differential mobility particle sizer (TSI-DMPS; 0.01-1+ micrometer diameters) after a single cigarette or cigar was machine-smoked inside a low air-exchange-rate 20 m{sup 3} chamber. The aerosol dynamics model provided good fits to observed concentrations when using optimized values of mass emission rate and deposition rate for each particle size range as input. Small discrepancies observed in the first 1-2 hours after smoking are likely due to the effect of particle evaporation, a process neglected by the model. Size-specific ETS particle emission factors were fit with log-normal distributions, yielding an average mass median diameter of 0.2 micrometers and an average geometric standard deviation of 2.3 with no systematic differences between cigars and cigarettes. The equivalent total particle emission rate, obtained integrating each size distribution, was 0.2-0.7 mg/min for cigars and 0.7-0.9 mg/min for cigarettes.

Influence factors and forecast of carbon emission in China: structure adjustment for emission peak

Science.gov (United States)

Wang, B.; Cui, C. Q.; Li, Z. P.

2018-02-01

This paper introduced Principal Component Analysis and Multivariate Linear Regression Model to verify long-term balance relationships between Carbon Emissions and the impact factors. The integrated model of improved PCA and multivariate regression analysis model is attainable to figure out the pattern of carbon emission sources. Main empirical results indicate that among all selected variables, the role of energy consumption scale was largest. GDP and Population follow and also have significant impacts on carbon emission. Industrialization rate and fossil fuel proportion, which is the indicator of reflecting the economic structure and energy structure, have a higher importance than the factor of urbanization rate and the dweller consumption level of urban areas. In this way, some suggestions are put forward for government to achieve the peak of carbon emissions.

Emissions of trace gases from Australian temperate forest fires: emission factors and dependence on modified combustion efficiency

Science.gov (United States)

Guérette, Elise-Andrée; Paton-Walsh, Clare; Desservettaz, Maximilien; Smith, Thomas E. L.; Volkova, Liubov; Weston, Christopher J.; Meyer, Carl P.

2018-03-01

We characterised trace gas emissions from Australian temperate forest fires through a mixture of open-path Fourier transform infrared (OP-FTIR) measurements and selective ion flow tube mass spectrometry (SIFT-MS) and White cell FTIR analysis of grab samples. We report emission factors for a total of 25 trace gas species measured in smoke from nine prescribed fires. We find significant dependence on modified combustion efficiency (MCE) for some species, although regional differences indicate that the use of MCE as a proxy may be limited. We also find that the fire-integrated MCE values derived from our in situ on-the-ground open-path measurements are not significantly different from those reported for airborne measurements of smoke from fires in the same ecosystem. We then compare our average emission factors to those measured for temperate forest fires elsewhere (North America) and for fires in another dominant Australian ecosystem (savanna) and find significant differences in both cases. Indeed, we find that although the emission factors of some species agree within 20 %, including those of hydrogen cyanide, ethene, methanol, formaldehyde and 1,3-butadiene, others, such as acetic acid, ethanol, monoterpenes, ammonia, acetonitrile and pyrrole, differ by a factor of 2 or more. This indicates that the use of ecosystem-specific emission factors is warranted for applications involving emissions from Australian forest fires.

Small-Chamber Measurements of Chemical-Specific Emission Factors for Drywall

Energy Technology Data Exchange (ETDEWEB)

Maddalena, Randy; Russell, Marion; Apte, Michael G.

2010-06-01

Imported drywall installed in U.S. homes is suspected of being a source of odorous and potentially corrosive indoor pollutants. To support an investigation of those building materials by the Consumer Products Safety Commission (CPSC), Lawrence Berkeley National Laboratory (LBNL) measured chemical-specific emission factors for 30 samples of drywall materials. Emission factors are reported for 75 chemicals and 30 different drywall samples encompassing both domestic and imported stock and incorporating natural, synthetic, or mixed gypsum core material. CPSC supplied all drywall materials. First the drywall samples were isolated and conditioned in dedicated chambers, then they were transferred to small chambers where emission testing was performed. Four sampling and analysis methods were utilized to assess (1) volatile organic compounds, (2) low molecular weight carbonyls, (3) volatile sulfur compounds, and (4) reactive sulfur gases. LBNL developed a new method that combines the use of solid phase microextraction (SPME) with small emission chambers to measure the reactive sulfur gases, then extended that technique to measure the full suite of volatile sulfur compounds. The testing procedure and analysis methods are described in detail herein. Emission factors were measured under a single set of controlled environmental conditions. The results are compared graphically for each method and in detailed tables for use in estimating indoor exposure concentrations.

Emission factors of the iron and steel sector for the emission reporting; Emissionsfaktoren zur Eisen- und Stahlindustrie fuer die Emissionsberichterstattung

Energy Technology Data Exchange (ETDEWEB)

Hensmann, Michael; Haardt, Sebastian; Ebert, Dominik [Betriebsforschungsinstitut VDEh-Institut fuer Angewandte Forschung GmbH, Duesseldorf (Germany)

2012-10-15

The German Umweltbundesamt (UBA) records emission factors of important groups of emitters of the iron- and steelmaking industry in a central database named ''Zentrales System Emissionen'' (ZSE) since 1990. This data is being used for calculations of emission inventories. The main purposes are the generation of forecasts, calculating emissions of other plants and the appraisal of potential measures for reduction of pollution. This makes it possible to identify and appraise future problems and measures. Because of steadily increasing requirements to data quality and quality assurance, it became necessary to update the ZSE with characteristical emission data in order to give a representative view of relevant stages in the iron- and steelmaking industry with respect to emissions. In 2008, the VDEh-Betriebsforschungsinstitut (BFI) was assigned to determine up-to-date emission factors for the following relevant stages in the iron- and steelmaking industry: - sintering plant - coking plant - blast furnace - steel making (differentiated between oxygen and electric steel making) - production of rolled steel Due to a wide diversity of data quality, a consecutive project to determine the corresponding uncertainty of the emission factors was integrated into the ongoing project. This is necessary to create reliable forecasts of emissions and to meet national and international duties of reporting. The project was supported by 18 companies of the German iron- and steelmaking industry. A total of 40 relevant sources of emissions were identified within the five stages of steelmaking and taken into consideration. The emission data for documenting organic and inorganic components of harmful gas, heavy metals and air borne dusts in the ZSE was taken from the reports of emissions 2008 of the supporting companies and made up for a total of 63 plants. Due to a wide variety of data quality the emissions of point sources and diffuse sources are treated separately. While

Emissions from decentralised CHP plants 2007 - Energinet.dk Environmental project no. 07/1882. Project report 5 - Emission factors and emission inventory for decentralised CHP production

Energy Technology Data Exchange (ETDEWEB)

Nielsen, Malene; Nielsen, Ole-Kenneth; Thomsen, M.

2010-06-15

Updated emission factors for decentralised combined heat and power (CHP) plants with a capacity < 25MWe have been estimated based on project emission measurements as well as emission measurements performed in recent years that were collected. The emission factors valid for 2006/2007 have been estimated for the plant technologies: Municipal solid waste (MSW) incineration plants, plants combusting straw or wood, natural gas fuelled reciprocating engines, biogas fuelled engines, natural gas fuelled gas turbines, gas oil fuelled reciprocating engines, gas oil fuelled gas turbines, steam turbines combusting residual oil and reciprocating engines combusting biomass producer gas based on wood. The emission factors for MSW incineration plants are much lower than the emission factors that were estimated for year 2000. The considerable reduction in the emission factors is a result of lower emission limit values in Danish legislation since 2006 that has lead to installation of new and improved flue gas cleaning systems in most MSW incineration plants. For CHP plants combusting wood or straw no major technical improvements have been implemented. The emission factors for natural gas fuelled reciprocating engines have been reduced since year 2000 as a result of technical improvements that have been carried out due to lower emission limit values in Danish legislation. The NO{sub x} emission factor for natural gas fuelled gas turbines has decreased 62 % since year 2000. This is a result of installation of low-NO{sub x} burners in almost all gas turbines that has been necessary to meet new emission limits in Danish legislation. The emission measurements programme included screening of the emissions of HCB, PCB, PCDD/-F and PBDD/-F. Compared to the Danish national emission decentralized CHP plants are major emission sources for CH{sub 4}, NO{sub x}, SO{sub 2}, heavy metals and HCB. (author)

Revised methane emissions factors and spatially distributed annual carbon fluxes for global livestock

Energy Technology Data Exchange (ETDEWEB)

Wolf, Julie; Asrar, Ghassem R.; West, Tristram O.

2017-09-29

Background: Livestock play an important role in carbon cycling through consumption of biomass and emissions of methane. Recent research suggests that existing bottom-up inventories of livestock methane emissions in the US, such as those made using 2006 IPCC Tier 1 livestock emissions factors, are too low. This may be due to outdated information used to develop these emissions factors. In this study, we update information for cattle and swine by region, based on reported recent changes in animal body mass, feed quality and quantity, milk productivity, and management of animals and manure. We then use this updated information to calculate new livestock methane emissions factors for enteric fermentation in cattle, and for manure management in cattle and swine.

Temperature Dependence of Factors Controlling Isoprene Emissions

Science.gov (United States)

Duncan, Bryan N.; Yoshida, Yasuko; Damon, Megan R.; Douglass, Anne R.; Witte, Jacquelyn C.

2009-01-01

We investigated the relationship of variability in the formaldehyde (HCHO) columns measured by the Aura Ozone Monitoring Instrument (OMI) to isoprene emissions in the southeastern United States for 2005-2007. The data show that the inferred, regional-average isoprene emissions varied by about 22% during summer and are well correlated with temperature, which is known to influence emissions. Part of the correlation with temperature is likely associated with other causal factors that are temperature-dependent. We show that the variations in HCHO are convolved with the temperature dependence of surface ozone, which influences isoprene emissions, and the dependence of the HCHO column to mixed layer height as OMI's sensitivity to HCHO increases with altitude. Furthermore, we show that while there is an association of drought with the variation in HCHO, drought in the southeastern U.S. is convolved with temperature.

Emissions factors for gaseous and particulate pollutants from offshore diesel engine vessels in China

Science.gov (United States)

Zhang, F.; Chen, Y.; Tian, C.; Li, J.; Zhang, G.; Matthias, V.

2015-09-01

Shipping emissions have significant influence on atmospheric environment as well as human health, especially in coastal areas and the harbor districts. However, the contribution of shipping emissions on the environment in China still need to be clarified especially based on measurement data, with the large number ownership of vessels and the rapid developments of ports, international trade and shipbuilding industry. Pollutants in the gaseous phase (carbon monoxide, sulfur dioxide, nitrogen oxides, total volatile organic compounds) and particle phase (particulate matter, organic carbon, elemental carbon, sulfates, nitrate, ammonia, metals) in the exhaust from three different diesel engine power offshore vessels in China were measured in this study. Concentrations, fuel-based and power-based emissions factors for various operating modes as well as the impact of engine speed on emissions were determined. Observed concentrations and emissions factors for carbon monoxide, nitrogen oxides, total volatile organic compounds, and particulate matter were higher for the low engine power vessel than for the two higher engine power vessels. Fuel-based average emissions factors for all pollutants except sulfur dioxide in the low engine power engineering vessel were significantly higher than that of the previous studies, while for the two higher engine power vessels, the fuel-based average emissions factors for all pollutants were comparable to the results of the previous studies. The fuel-based average emissions factor for nitrogen oxides for the small engine power vessel was more than twice the International Maritime Organization standard, while those for the other two vessels were below the standard. Emissions factors for all three vessels were significantly different during different operating modes. Organic carbon and elemental carbon were the main components of particulate matter, while water-soluble ions and elements were present in trace amounts. Best-fit engine speeds

Temporal and spatial variation in recent vehicular emission inventories in China based on dynamic emission factors.

Science.gov (United States)

Cai, Hao; Xie, Shaodong

2013-03-01

The vehicular emission trend in China was tracked for the recent period 2006-2009 based on a database of dynamic emission factors of CO, nonmethane volatile organic compounds (NMVOC), NOx, PM10, CO2, CH4, and N2O for all categories of on-road motor vehicles in China, which was developed at the provincial level using the COPERT 4 model, to account for the effects of rapid advances in engine technologies, implementation of improved emission standards, emission deterioration due to mileage, and fuel quality improvement. Results show that growth rates of CO and NMVOC emissions slowed down, but NOx and PM10 emissions continued rising rapidly for the period 2006-2009. Moreover CO2, CH4, and N2O emissions in 2009 almost doubled compared to those in 2005. Characteristics of recent spatial distribution of emissions and emission contributions by vehicle category revealed that priority of vehicular emission control should be put on the eastern and southeastern coastal provinces and northern regions, and passenger cars and motorcycles require stricter control for the reduction of CO and NMVOC emissions, while effective reduction of NOx and PM10 emissions can be achieved by better control of heavy-duty vehicles, buses and coaches, and passenger cars. Explicit provincial-level Monte Carlo uncertainty analysis, which quantified for the first time the Chinese vehicular emission uncertainties associated with both COPERT-derived and domestically measured emission factors by vehicle technology, showed that CO, NMVOC, and NOx emissions for the period 2006-2009 were calculated with the least uncertainty, followed by PM10 and CO2, despite relatively larger uncertainties in N2O and CH4 emissions. The quantified low uncertainties of emissions revealed a necessity of applying vehicle technology- and vehicle age-specific dynamic emission factors for vehicular emission estimation, and these improved methodologies are applicable for routine update and forecast of China's on-road motor vehicle

Analysis of regional difference on impact factors of China’s energy – Related CO2 emissions

International Nuclear Information System (INIS)

Li, Huanan; Mu, Hailin; Zhang, Ming; Gui, Shusen

2012-01-01

With the intensification of global warming, the issue of carbon emissions causes more and more attention in recent years. In this paper, China’s 30 provincial-level administrative units are divided into five emission regions according to the annual average value of provincial CO 2 emissions per capita during 1990 and 2010. The regional differences in impact factors on CO 2 emissions are discussed using STIRPAT (stochastic impacts by regression on population, affluence, and technology) model. The results indicate that although GDP (Gross domestic product) per capita, industrial structure, population, urbanization and technology level have different impacts on CO 2 emissions in different emission regions, they are almost always the main factors in all emission regions. In most emission regions, urbanization and GDP per capita has a bigger impact on CO 2 emissions than other factors. Improving technology level produces a small reduction in CO 2 emissions in most emission regions, but it is still a primary way for CO 2 reduction in China. It’s noteworthy that industrial structure isn’t the main factor and improving technology level increases CO 2 emissions in high emission region. Different measures should be adopted for CO 2 reductions according to local conditions in different regions. -- Highlights: ► Regional differences of the impact factors on China’s CO 2 emissions are analyzed. ► Five macro factors like GDP per capita are almost always main influence factors in all regions. ► The impacts of different factors are different. ► Improving technology has no significant reduction on CO 2 emission in most regions. ► Policy on CO 2 reduction should be adapted to local conditions.

Measurements of air pollution emission factors for marine transportation in SECA

Directory of Open Access Journals (Sweden)

B. Alföldy

2013-07-01

Full Text Available The chemical composition of the plumes of seagoing ships was measured during a two week long measurement campaign in the port of Rotterdam, Hoek van Holland The Netherlands, in September 2009. Altogether, 497 ships were monitored and a statistical evaluation of emission factors (g kg−1 fuel was provided. The concerned main atmospheric components were SO2, NO2, NOx and the aerosol particle number. In addition, the elemental and water-soluble ionic composition of the emitted particulate matter was determined. Emission factors were expressed as a function of ship type, power and crankshaft rotational speed. The average SO2 emission factor was found to be roughly half of what is allowed in sulphur emission control areas (16 vs. 30 g kg−1 fuel, and exceedances of this limit were rarely registered. A significant linear relationship was observed between the SO2 and particle number emission factors. The intercept of the regression line, 4.8 × 1015 (kg fuel−1, gives the average number of particles formed during the burning of 1 kg zero sulphur content fuel, while the slope, 2 × 1018, provides the average number of particles formed with 1 kg sulphur burnt with the fuel. Water-soluble ionic composition analysis of the aerosol samples from the plumes showed that ~144 g of particulate sulphate was emitted from 1 kg sulphur burnt with the fuel. The mass median diameter of sulphate particles estimated from the measurements was ~42 nm.

Analysis on influence factors of China's CO2 emissions based on Path-STIRPAT model

International Nuclear Information System (INIS)

Li Huanan; Mu Hailin; Zhang Ming; Li Nan

2011-01-01

With the intensification of global warming and continued growth in energy consumption, China is facing increasing pressure to cut its CO 2 (carbon dioxide) emissions down. This paper discusses the driving forces influencing China's CO 2 emissions based on Path-STIRPAT model-a method combining Path analysis with STIRPAT (stochastic impacts by regression on population, affluence and technology) model. The analysis shows that GDP per capita (A), industrial structure (IS), population (P), urbanization level (R) and technology level (T) are the main factors influencing China's CO 2 emissions, which exert an influence interactively and collaboratively. The sequence of the size of factors' direct influence on China's CO 2 emission is A>T>P>R>IS, while that of factors' total influence is A>R>P>T>IS. One percent increase in A, IS, P, R and T leads to 0.44, 1.58, 1.31, 1.12 and -1.09 percentage change in CO 2 emission totally, where their direct contribution is 0.45, 0.07, 0.63, 0.08, 0.92, respectively. Improving T is the most important way for CO 2 reduction in China. - Highlights: → We analyze the driving forces influencing China's CO 2 emissions. → Five macro factors like per capita GDP are the main influencing factors. → These factors exert an influence interactively and collaboratively. → Different factors' direct and total influence on China's CO 2 emission is different. → Improving technology level is the most important way for CO 2 reduction in China.

Revised methane emissions factors and spatially distributed annual carbon fluxes for global livestock.

Science.gov (United States)

Wolf, Julie; Asrar, Ghassem R; West, Tristram O

2017-09-29

Livestock play an important role in carbon cycling through consumption of biomass and emissions of methane. Recent research suggests that existing bottom-up inventories of livestock methane emissions in the US, such as those made using 2006 IPCC Tier 1 livestock emissions factors, are too low. This may be due to outdated information used to develop these emissions factors. In this study, we update information for cattle and swine by region, based on reported recent changes in animal body mass, feed quality and quantity, milk productivity, and management of animals and manure. We then use this updated information to calculate new livestock methane emissions factors for enteric fermentation in cattle, and for manure management in cattle and swine. Using the new emissions factors, we estimate global livestock emissions of 119.1 ± 18.2 Tg methane in 2011; this quantity is 11% greater than that obtained using the IPCC 2006 emissions factors, encompassing an 8.4% increase in enteric fermentation methane, a 36.7% increase in manure management methane, and notable variability among regions and sources. For example, revised manure management methane emissions for 2011 in the US increased by 71.8%. For years through 2013, we present (a) annual livestock methane emissions, (b) complete annual livestock carbon budgets, including carbon dioxide emissions, and (c) spatial distributions of livestock methane and other carbon fluxes, downscaled to 0.05 × 0.05 degree resolution. Our revised bottom-up estimates of global livestock methane emissions are comparable to recently reported top-down global estimates for recent years, and account for a significant part of the increase in annual methane emissions since 2007. Our results suggest that livestock methane emissions, while not the dominant overall source of global methane emissions, may be a major contributor to the observed annual emissions increases over the 2000s to 2010s. Differences at regional and local scales may help

Influence of economic factors on future global emissions

International Nuclear Information System (INIS)

Duffey, R.B.; Poehnell, T.G.; Miller, A.I.; Tamm, J.A.

2001-01-01

The climate change debate is really about economics, and reducing greenhouse gas (GHG) emissions and climate change potential at a reasonable and acceptable cost for everyone. In this paper, we examine the major economic factors behind defining climate change policies that relate to reducing GHG emissions, and the value to be placed on CO 2 . We examine the impacts and the 'cost of carbon' based on the studies of GHG reduction strategies in the US and the European Union (EU). We show that a series of self-defeating assumptions have been used in the latest analyses regarding relative future energy and power costs, and hence future GHG emissions. We estimate: the 'natural value' of GHG emissions based on world economic factors, the value of electricity and energy based on world data, the cost advantage of using a given new technology, and the value of avoided GHG emissions in future global and national climate change projections. The use of electricity is shown to be key in aiding economic growth for the entire world. Using the latest Intergovernmental Panel on Climate Change (IPCC) 2000 climate change projections as a base, we reflect the impacts of differing energy prices on future global climate conditions and GHG reductions. We conduct a similar analysis for Canada using the latest 'Energy in Canada 2000' projections. We show how the use of advanced technology for the traditional production of electricity, and for hydrogen-based transportation fuels, can stabilize global emissions and assist in managing adverse climate change conditions without causing economic penalties. The method we develop is sufficiently general that it can be used for valuing the economic impact of the emission reductions for any technology. We estimate the embedded value and potential economic benefit of nuclear technology and electric contribution for both the world economy to 2100, and for the latest projections for Canada to 2020. (author)

Improved Rice Residue Burning Emissions Estimates: Accounting for Practice-Specific Emission Factors in Air Pollution Assessments of Vietnam

Science.gov (United States)

Lasko, Kristofer; Vadrevu, Krishna

2018-01-01

In Southeast Asia and Vietnam, rice residues are routinely burned after the harvest to prepare fields for the next season. Specific to Vietnam, the two prevalent burning practices include: a). piling the residues after hand harvesting; b). burning the residues without piling, after machine harvesting. In this study, we synthesized field and laboratory studies from the literature on rice residue burning emission factors for Particulate Matter less than 2.5 microns (PM2.5). We found significant differences in the resulting burning-practice specific emission factors, with 16.9 grams per square kilogram (plus or minus 6.9) for pile burning and 8.8 grams per square kilogram (plus or minus 3.5) for non-pile burning. We calculated burning practice specific emissions based on rice area data, region-specific fuel-loading factors, combined emission factors, and estimates of burning from the literature. Our results for year 2015 estimate 180 gigagrams of PM2.5 result from the pile burning method and 130 gigagrams result from non-pile burning method, with the most-likely current emission scenario of 150 gigagrams PM2.5 emissions for Vietnam. For comparison purposes, we calculated emissions using generalized agricultural emission factors employed in global biomass burning studies. These results estimate 80 gigagrams PM2.5, which is only 44 percent of the pile burning-based estimates, suggesting underestimation in previous studies. We compare our emissions to an existing all-combustion sources inventory, results show emissions account for 14-18 percent of Vietnam's total PM2.5 depending on burning practice. Within the highly-urbanized and cloud-covered Hanoi Capital region (HCR), we use rice area from Sentinel-1A to derive spatially-explicit emissions and indirectly estimate residue burning dates. Results from HYSPLIT (Hybrid Single-Particle Lagrangian Integrated Trajectory) back-trajectory analysis stratified by season show autumn has most emission trajectories originating in

Real-time black carbon emission factor measurements from light duty vehicles.

Science.gov (United States)

Forestieri, Sara D; Collier, Sonya; Kuwayama, Toshihiro; Zhang, Qi; Kleeman, Michael J; Cappa, Christopher D

2013-11-19

Eight light-duty gasoline low emission vehicles (LEV I) were tested on a Chassis dynamometer using the California Unified Cycle (UC) at the Haagen-Smit vehicle test facility at the California Air Resources Board in El Monte, CA during September 2011. The UC includes a cold start phase followed by a hot stabilized running phase. In addition, a light-duty gasoline LEV vehicle and ultralow emission vehicle (ULEV), and a light-duty diesel passenger vehicle and gasoline direct injection (GDI) vehicle were tested on a constant velocity driving cycle. A variety of instruments with response times ≥0.1 Hz were used to characterize how the emissions of the major particulate matter components varied for the LEVs during a typical driving cycle. This study focuses primarily on emissions of black carbon (BC). These measurements allowed for the determination of BC emission factors throughout the driving cycle, providing insights into the temporal variability of BC emission factors during different phases of a typical driving cycle.

Real-world vehicle emission factors in Chinese metropolis city--Beijing.

Science.gov (United States)

Wang, Qi-dong; He, Ke-bin; Huo, Hong; Lents, James

2005-01-01

The dynamometer tests with different driving cycles and the real-world tests are presented. Results indicated the pollutants emission factors and fuel consumption factor with ECE15 + EUDC driving cycle usually take the lowest value and with real world driving cycle occur the highest value, and different driving cycles will lead to significantly different vehicle emission factors with the same vehicle. Relative to the ECE15 + EUDC driving cycle, the increasing rate of pollutant emission factors of CO, NOx and HC are - 0.42-2.99, -0.32-0.81 and -0.11-11 with FTP75 testing, 0.11-1.29, -0.77-0.64 and 0.47-10.50 with Beijing 1997 testing and 0.25-1.83, 0.09-0.75 and - 0.58-1.50 with real world testing. Compared to the carburetor vehicles, the retrofit and MPI + TWC vehicles' pollution emissionfactors decrease with different degree. The retrofit vehicle (Santana) will reduce 4.44%-58.44% CO, -4.95%-36.79% NOx, -32.32%-33.89% HC, and -9.39%-14.29% fuel consumption, and especially that the MPI + TWC vehicle will decrease CO by 82.48%-91.76%, NOx by 44.87%-92.79%, HC by 90.00%-93.89% and fuel consumption by 5.44%-10.55%. Vehicles can cause pollution at a very high rate when operated in high power modes; however, they may not often operate in these high power modes. In analyzing vehicle emissions, it describes the fraction of time that vehicles operate in various power modes. In Beijing, vehicles spend 90% of their operation in low power modes or decelerating.

78 FR 64496 - Acid Rain Program: Notice of Annual Adjustment Factors for Excess Emissions Penalty

Science.gov (United States)

2013-10-29

... Factors for Excess Emissions Penalty AGENCY: Environmental Protection Agency (EPA). ACTION: Notice of annual adjustment factors for excess emissions penalty. SUMMARY: The Acid Rain Program under title IV of... excess tons emitted times $2,000 as adjusted by an annual adjustment factor, which must be published in...

Factors influencing CO2 emissions in China's power industry: Co-integration analysis

International Nuclear Information System (INIS)

Zhao, Xiaoli; Ma, Qian; Yang, Rui

2013-01-01

More than 40% of China's total CO 2 emissions originate from the power industry. The realization of energy saving and emission reduction within China's power industry is therefore crucial in order to achieve CO 2 emissions reduction in this country. This paper applies the autoregressive-distributed lag (ARDL) co-integration model to study the major factors which have influenced CO 2 emissions within China's power industry from 1980 to 2010. Results have shown that CO 2 emissions from China's power industry have been increasing rapidly. From 1980 to 2010, the average annual growth rate was 8.5%, and the average growth rate since 2002 has amounted to 10.5%. Secondly, the equipment utilization hour (as an indicator of the power demand) has the greatest influence on CO 2 emissions within China's power industry. In addition, the impact of the industrial added value of the power sector on CO 2 emissions is also positive from a short-term perspective. Thirdly, the Granger causality results imply that one of the important motivators behind China's technological progress, within the power industry, originates from the pressures created by a desire for CO 2 emissions reduction. Finally, this paper provides policy recommendations for energy saving and emission reduction for China's power industry. - Highlights: ► We study the major factors influencing China's power industry CO 2 emissions. ► The average annual growth rate of CO 2 emission from power industry is calculated. ► Installed capacity has the greatest influence on power industry CO 2 emission. ► The Granger causality between CO 2 emission and its effecting factors is analyzed

Emission factors of carbonaceous particulate matter and polycyclic aromatic hydrocarbons from residential solid fuel combustions

Energy Technology Data Exchange (ETDEWEB)

Shen, Guofeng [Jiangsu Academy of Environmental Science, Nanjing (China). Inst. of Atmospheric Sciences

2014-07-01

Emission inventory is basic for the understanding of environmental behaviors and potential effects of compounds, however, current inventories are often associated with relatively high uncertainties. One important reason is the lack of emission factors, especially for the residential solid fuel combustion in developing countries. In the present study, emission factors of a group of pollutants including particulate matter, organic carbon, elemental carbon (sometimes known as black carbon) and polycyclic aromatic hydrocarbons were measured for a variety of residential solid fuels including coal, crop straw, wood, and biomass pellets in rural China. The study provided a large number of emission factors that can be further used in emission estimation. Composition profiles and isomer ratios were investigated and compared so as to be used in source apportionment. In addition, the present study identified and quantified the influence of factors like fuel moisture, volatile matter on emission performance.

Real world vehicle fleet emission factors: Seasonal and diurnal variations in traffic related air pollutants

Science.gov (United States)

Wang, Jonathan M.; Jeong, Cheol-Heon; Zimmerman, Naomi; Healy, Robert M.; Evans, Greg J.

2018-07-01

Temporal variations of vehicle emissions are affected by various compounding factors in the real world. The focus of this study is to determine the effects of ambient conditions and post-tailpipe changes on traffic emissions measured in the near-road region. Emission factors allowed for the isolation of the traffic signal and accounted for effects of local meteorology and dilution. Five month-long measurement campaigns were conducted at an urban near-road site that exhibited a broad range of ambient conditions with temperatures ranging between -18 and +30 °C. Particle number emission factors were 2.0× higher in the winter relative to the summer, which was attributed to changes in particles post-tailpipe. Conversely, toluene emissions were 2.5× higher in the summer relative to the winter, attributed to changes in fuel composition. Diurnal trends of emission factors showed substantial increases in emissions during the morning rush hour for black carbon (1.9×), particle number (2.4×), and particle-bound polycyclic aromatic hydrocarbons (3.0×), affected by fleet make-up. In contrast, particle number emission factors were highest midday with mean values 3.7× higher than at night. This midday increase was attributed to particle formation or growth from local traffic emissions and showed different wind direction dependence than regional events.

Tailpipe, resuspended road dust, and brake-wear emission factors from on-road vehicles

Science.gov (United States)

Abu-Allaban, Mahmoud; Gillies, John A.; Gertler, Alan W.; Clayton, Russ; Proffitt, David

Intensive mass and chemical measurements were performed at roadside locations in Reno, Nevada, and Durham/Research Triangle Park), North Carolina to derive tailpipe, resuspended road dust, and brake-wear emission factors from in-use vehicles. Continuous particulate matter (PM) data were utilized to derive total emission factors while integrated PM data were used to attribute the calculated emission factors to different mechanisms using chemical mass balance receptor modeling and scanning electron microscopy techniques. Resuspended road dust and tailpipe emissions were found to be the dominant mechanisms that contribute significantly to the total PM 10 and PM 2.5 emission factors, respectively. Small contributions from brake-wear were observed at locations where strong braking occurs, but no tire-wear was seen at any sampling location. PM 10 emission rates from light-duty spark ignition (LDSI) vehicles ranged from 40 to 780 mg/km, 10 to 70 mg/km, and 0 to 80 mg/km per vehicle for road dust, tailpipe, and brake-wear, respectively. PM 10 emission rates from heavy-duty vehicles ranged from 230 to 7800 mg/km, 60 to 570 mg/km, and 0 to 610 mg/km per vehicle for road dust, tailpipe, and brake-wear, respectively. PM 2.5 emission rates from LDSI vehicles ranged from 2 to 25 mg/km, 10 to 50 mg/km, and 0 to 5 mg/km per vehicle for road dust, tailpipe, and brake-wear, respectively. PM 2.5 emission rates from heavy-duty vehicles ranged from 15 to 300 mg/km, 60 to 480 mg/km, and 0 to 15 mg/km per vehicle for road dust, tailpipe, and brake-wear, respectively.

CO2 emission factors for waste incineration: Influence from source separation of recyclable materials

DEFF Research Database (Denmark)

Larsen, Anna Warberg; Astrup, Thomas

2011-01-01

variations between emission factors for different incinerators, but the background for these variations has not been thoroughly examined. One important reason may be variations in collection of recyclable materials as source separation alters the composition of the residual waste incinerated. The objective...... routed to incineration. Emission factors ranged from 27 to 40kg CO2/GJ. The results appeared most sensitive towards variations in waste composition and water content. Recycling rates and lower heating values could not be used as simple indicators of the resulting emission factors for residual household...... different studies and when using the values for environmental assessment purposes....

Emission factors from biomass burning in three types of appliances: fireplace, woodstove and pellet stove

Science.gov (United States)

Duarte, Márcio; Vicente, Estela; Calvo, Ana; Nunes, Teresa; Tarelho, Luis; Alves, Célia

2014-05-01

In the last years, the importance of biomass fuels has increased mainly for two reasons. One of them is the effort to control the emissions of greenhouse gases, and on the other hand, the increasing costs associated with fossil fuels. Besides that, biomass burning is now recognised as one of the major sources contributing to high concentrations of particulate matter, especially during winter time. Southern European countries have a lack of information regarding emission profiles from biomass burning. Because of that, in most source apportionment studies, the information used comes from northern and alpine countries, whose combustion appliances, fuels and habits are different from those in Mediterranean countries. Due to this lack of information, series of tests using different types of equipment, as well as fuels, were carried out in order to obtain emission profiles and emission factors that correspond to the reality in southern European countries. Tests involved three types of biomass appliances used in Portugal, a fireplace, a woodstove and a modern pellet stove. Emission factors (mg.kg-1 fuel, dry basis) for CO, THC and PM10 were obtained. CO emission factors ranged from 38, for pine on the woodstove, to 84 for eucalyptus in the fireplace. THC emissions were between 4 and 24, for pine in the woodstove and eucalyptus in the fireplace, respectively. PM10 emission factors were in the range from 3.99, for pine in the woodstove, to 17.3 for eucalyptus in the fireplace. On average, the emission factors obtained for the fireplace are 1.5 (CO) to 4 (THC) times higher than those of the woodstove. The fireplace has emission factors for CO, THC and PM10 10, 35 and 32 times, respectively, higher than the pellet stove.

Emission factors for CH{sub 4}, NO{sub x}, particulates and black carbon for domestic shipping in Norway, revision 1

Energy Technology Data Exchange (ETDEWEB)

Nielsen, Joergen Bremnes; Stenersen, Dag

2010-11-15

In this report new and updated emission factors for diesel, HFO and gas fuelled ships are presented and discussed as follows; NO{sub x} reduction factors from ships with NO{sub x} reduction measures; NO{sub x} emission factor from gas operated vessels; Methane emission factors for gas operated vessels; Updated emission factors for particulate emissions (PM) with a specific factor for the black carbon (BC) fraction of particulate emissions; A discussion on how low sulfur fuel will affect emissions of PM emissions and the BC fraction of PM is also included. (Author)

Accuracy of exhaust emission factor measurements on chassis dynamometer

NARCIS (Netherlands)

Joumard, R.; Laurikko, J.; Han, T.L.; Geivanidis, S.; Samaras, Z.; Merétei, T.; Devaux, P.; André, J.-M.; Cornelis, E.; Lacour, S.; Prati, M.V.; Vermeulen, R.; Zallinger, M.

2009-01-01

The influence of 20 parameters on the measurement of light-vehicle emission factors on chassis dynamometer based on driving patterns, vehicle-related parameters, vehicle sampling, and laboratory-related parameters, was studied. The results were based on literature synthesis, ≈ 2700 specific tests

A Study on Vehicle Emission Factor Correction Based on Fuel Consumption Measurement

Science.gov (United States)

Wang, Xiaoning; Li, Meng; Peng, Bo

2018-01-01

The objective of this study is to address the problem of obvious differences between the calculated and measured emissions of pollutants from motor vehicle by using the existing "Environmental Impact Assessment Specification of Highway Construction Projects". First, a field study collects the vehicle composition ratio, speed, slope, fuel consumption and other essential data. Considering practical applications, the emission factors corresponding to 40km/h and 110km/h and 120km/h velocity are introduced by data fitting. Then, the emission factors of motor vehicle are revised based on the measured fuel consumption, and the pollutant emission modified formula was calculated and compared with the standard recommendation formula. The results show the error between calculated and measured values are within 5%, which can better reflect the actual discharge of the motor vehicle.

Development of cotton gin PM10 emission factors for EPA’s AP-42-DUPLICATE DO NOT USE

Science.gov (United States)

The Compilation of Air Pollution Emission Factors (AP-42) emission factors are assigned ratings, from A (Excellent) to E (Poor), based on the quality of data used to develop them. All current PM10 cotton gin emission factors received quality ratings of D or lower. In an effort to improve these ratin...

GHG emission factors developed for the recycling and composting of municipal waste in South African municipalities

Energy Technology Data Exchange (ETDEWEB)

Friedrich, Elena, E-mail: Friedriche@ukzn.ac.za; Trois, Cristina

2013-11-15

Highlights: • GHG emission factors for local recycling of municipal waste are presented. • GHG emission factors for two composting technologies for garden waste are included. • Local GHG emission factors were compared to international ones and discussed. • Uncertainties and limitations are presented and areas for new research highlighted. - Abstract: GHG (greenhouse gas) emission factors for waste management are increasingly used, but such factors are very scarce for developing countries. This paper shows how such factors have been developed for the recycling of glass, metals (Al and Fe), plastics and paper from municipal solid waste, as well as for the composting of garden refuse in South Africa. The emission factors developed for the different recyclables in the country show savings varying from −290 kg CO{sub 2} e (glass) to −19 111 kg CO{sub 2} e (metals – Al) per tonne of recyclable. They also show that there is variability, with energy intensive materials like metals having higher GHG savings in South Africa as compared to other countries. This underlines the interrelation of the waste management system of a country/region with other systems, in particular with energy generation, which in South Africa, is heavily reliant on coal. This study also shows that composting of garden waste is a net GHG emitter, releasing 172 and 186 kg CO{sub 2} e per tonne of wet garden waste for aerated dome composting and turned windrow composting, respectively. The paper concludes that these emission factors are facilitating GHG emissions modelling for waste management in South Africa and enabling local municipalities to identify best practice in this regard.

GHG emission factors developed for the recycling and composting of municipal waste in South African municipalities

International Nuclear Information System (INIS)

Friedrich, Elena; Trois, Cristina

2013-01-01

Highlights: • GHG emission factors for local recycling of municipal waste are presented. • GHG emission factors for two composting technologies for garden waste are included. • Local GHG emission factors were compared to international ones and discussed. • Uncertainties and limitations are presented and areas for new research highlighted. - Abstract: GHG (greenhouse gas) emission factors for waste management are increasingly used, but such factors are very scarce for developing countries. This paper shows how such factors have been developed for the recycling of glass, metals (Al and Fe), plastics and paper from municipal solid waste, as well as for the composting of garden refuse in South Africa. The emission factors developed for the different recyclables in the country show savings varying from −290 kg CO 2 e (glass) to −19 111 kg CO 2 e (metals – Al) per tonne of recyclable. They also show that there is variability, with energy intensive materials like metals having higher GHG savings in South Africa as compared to other countries. This underlines the interrelation of the waste management system of a country/region with other systems, in particular with energy generation, which in South Africa, is heavily reliant on coal. This study also shows that composting of garden waste is a net GHG emitter, releasing 172 and 186 kg CO 2 e per tonne of wet garden waste for aerated dome composting and turned windrow composting, respectively. The paper concludes that these emission factors are facilitating GHG emissions modelling for waste management in South Africa and enabling local municipalities to identify best practice in this regard

Nitrous oxide emission factors from N-fertilizer in sugarcane production in Brazil

Science.gov (United States)

Galdos, M. V.; Siqueira Neto, M.; Feigl, B. J.; Carvalho, J. L.; Cerri, C. E.; Cerri, C. C.

2013-12-01

The Brazilian sugarcane production is rapidly expanding due to the increase of global demand for ethanol. Concurrently the necessary inputs to culture, especially N-fertilizer, are growing, since N is one of the key element to maintain sugarcane productivity. However, it is known that N-fertilizer is responsible for the largest share of N2O emissions from agricultural soils. The Intergovernmental Panel on Climate Changes (IPCC) estimated that under favorable climatic conditions approximately 1% of the N-fertilizer applied can be emitted as N2O. Our goal was to estimate N2O emission factors from N-fertilizer used in the sugarcane ratoon for ethanol production. A field study was conducted at the Capuava Mill, located in southeastern Brazil. The experimental design was completely randomized, with four replications in a factorial scheme (2 x 2): two N sources (urea and ammonium nitrate), two application rates (80 and 120 kg ha-1), and a control treatment. N2O concentrations were determined by gas chromatography using a Shimadzu© GC-mini. N2O fluxes were calculated from linear regressions of concentration versus incubation time in the soil static chambers. The N2O emission factor of N-fertilizer was calculated according to the methodology described in the Guidelines for National Greenhouse Gas Inventories (IPCC). Comparatively, ammonium nitrate emitted 45 to 75% less N2O than urea application. There was no significant difference in N2O emission between the two applied rates of urea. Also the N2O emission factor of ammonium nitrate (0.3×0.2%) was lower than that of urea (1.1×0.4%). Our results indicated that on average the N fertilization of sugarcane plantation has an emission factor of 0.7×0.5% suggesting that N-fertilizer management can be used to reduce greenhouse gas emissions in order to improve the sustainability of bioethanol from sugarcane.

Greenhouse gas emission factor development for coal-fired power plants in Korea

International Nuclear Information System (INIS)

Jeon, Eui-Chan; Myeong, Soojeong; Sa, Jae-Whan; Kim, Jinsu; Jeong, Jae-Hak

2010-01-01

Accurate estimation of greenhouse gas emissions is essential for developing an appropriate strategy to mitigate global warming. This study examined the characteristics of greenhouse gas emission from power plants, a major greenhouse gas source in Korea. The power plants examined use bituminous coal, anthracite, and sub-bituminous coal as fuel. The CO 2 concentration from power plants was measured using GC-FID with methanizer. The amount of carbon, hydrogen, and calorific values in the input fuel was measured using an elemental analyzer and calorimeter. For fuel analysis, CO 2 emission factors for anthracite, bituminous coal, and sub-bituminous coal were 108.9, 88.4, and 97.9 Mg/kJ, respectively. The emission factors developed in this study were compared with those for IPCC. The results showed that CO 2 emission was 10.8% higher for anthracite, 5.5% lower for bituminous coal, and 1.9% higher for sub-bituminous coal than the IPCC figures.

Emission factors for gaseous and particulate pollutants from offshore diesel engine vessels in China

Science.gov (United States)

Zhang, Fan; Chen, Yingjun; Tian, Chongguo; Lou, Diming; Li, Jun; Zhang, Gan; Matthias, Volker

2016-05-01

Shipping emissions have significant influence on atmospheric environment as well as human health, especially in coastal areas and the harbour districts. However, the contribution of shipping emissions on the environment in China still need to be clarified especially based on measurement data, with the large number ownership of vessels and the rapid developments of ports, international trade and shipbuilding industry. Pollutants in the gaseous phase (carbon monoxide, sulfur dioxide, nitrogen oxides, total volatile organic compounds) and particle phase (particulate matter, organic carbon, elemental carbon, sulfates, nitrate, ammonia, metals) in the exhaust from three different diesel-engine-powered offshore vessels in China (350, 600 and 1600 kW) were measured in this study. Concentrations, fuel-based and power-based emission factors for various operating modes as well as the impact of engine speed on emissions were determined. Observed concentrations and emission factors for carbon monoxide, nitrogen oxides, total volatile organic compounds, and particulate matter were higher for the low-engine-power vessel (HH) than for the two higher-engine-power vessels (XYH and DFH); for instance, HH had NOx EF (emission factor) of 25.8 g kWh-1 compared to 7.14 and 6.97 g kWh-1 of DFH, and XYH, and PM EF of 2.09 g kWh-1 compared to 0.14 and 0.04 g kWh-1 of DFH, and XYH. Average emission factors for all pollutants except sulfur dioxide in the low-engine-power engineering vessel (HH) were significantly higher than that of the previous studies (such as 30.2 g kg-1 fuel of CO EF compared to 2.17 to 19.5 g kg-1 fuel in previous studies, 115 g kg-1 fuel of NOx EF compared to 22.3 to 87 g kg-1 fuel in previous studies and 9.40 g kg-1 fuel of PM EF compared to 1.2 to 7.6 g kg-1 fuel in previous studies), while for the two higher-engine-power vessels (DFH and XYH), most of the average emission factors for pollutants were comparable to the results of the previous studies, engine type was

Research on impacts of population-related factors on carbon emissions in Beijing from 1984 to 2012

International Nuclear Information System (INIS)

Yang, Yayun; Zhao, Tao; Wang, Yanan; Shi, Zhaohui

2015-01-01

Carbon emissions related to population factors have aroused great attention around the world. A multitude of literature mainly focused on single demographic impacts on environmental issues at the national level, and comprehensive studies concerning population-related factors at a city level are rare. This paper employed STIRPAT (Stochastic Impacts by Regression on Population, Affluence and Technology) model incorporating PLS (Partial least squares) regression method to examine the influence of population-related factors on carbon emissions in Beijing from 1984 to 2012. Empirically results manifest that urbanization is the paramount driver. Changes in population age structure have significantly positive impacts on carbon emissions, and shrinking young population, continuous expansion of working age population and aging population will keep on increasing environmental pressures. Meanwhile, shrinking household size and expanding floating population boost the discharge of carbon emissions. Besides, per capita consumption is an important contributor of carbon emissions, while industry energy intensity is the main inhibitory factor. Based upon these findings and the specific circumstances of Beijing, policies such as promoting clean and renewable energy, improving population quality and advocating low carbon lifestyles should be enhanced to achieve targeted emissions reductions. - Highlights: • We employed the STIRPAT model to identify population-related factors of carbon emissions in Beijing. • Urbanization is the paramount driver of carbon emissions. • Changes in population age structure exert significantly positive impacts on carbon emissions. • Shrinking household size, expanding floating population and improving consumption level increase carbon emissions. • Industry energy intensity decreases carbon emissions

Research on impacts of population-related factors on carbon emissions in Beijing from 1984 to 2012

Energy Technology Data Exchange (ETDEWEB)

Yang, Yayun; Zhao, Tao; Wang, Yanan, E-mail: wyn3615@126.com; Shi, Zhaohui

2015-11-15

Carbon emissions related to population factors have aroused great attention around the world. A multitude of literature mainly focused on single demographic impacts on environmental issues at the national level, and comprehensive studies concerning population-related factors at a city level are rare. This paper employed STIRPAT (Stochastic Impacts by Regression on Population, Affluence and Technology) model incorporating PLS (Partial least squares) regression method to examine the influence of population-related factors on carbon emissions in Beijing from 1984 to 2012. Empirically results manifest that urbanization is the paramount driver. Changes in population age structure have significantly positive impacts on carbon emissions, and shrinking young population, continuous expansion of working age population and aging population will keep on increasing environmental pressures. Meanwhile, shrinking household size and expanding floating population boost the discharge of carbon emissions. Besides, per capita consumption is an important contributor of carbon emissions, while industry energy intensity is the main inhibitory factor. Based upon these findings and the specific circumstances of Beijing, policies such as promoting clean and renewable energy, improving population quality and advocating low carbon lifestyles should be enhanced to achieve targeted emissions reductions. - Highlights: • We employed the STIRPAT model to identify population-related factors of carbon emissions in Beijing. • Urbanization is the paramount driver of carbon emissions. • Changes in population age structure exert significantly positive impacts on carbon emissions. • Shrinking household size, expanding floating population and improving consumption level increase carbon emissions. • Industry energy intensity decreases carbon emissions.

Emission factor of ammonia (NH3) from on-road vehicles in China: tunnel tests in urban Guangzhou

Science.gov (United States)

Liu, Tengyu; Wang, Xinming; Wang, Boguang; Ding, Xiang; Deng, Wei; Lü, Sujun; Zhang, Yanli

2014-05-01

Ammonia (NH3) is the primary alkaline gas in the atmosphere that contributes to formation of secondary particles. Emission of NH3 from vehicles, particularly gasoline powered light duty vehicles equipped with three-way catalysts, is regarded as an important source apart from emissions from animal wastes and soils, yet measured emission factors for motor vehicles are still not available in China, where traffic-related emission has become an increasingly important source of air pollutants in urban areas. Here we present our tunnel tests for NH3 from motor vehicles under ‘real world conditions’ in an urban roadway tunnel in Guangzhou, a central city in the Pearl River Delta (PRD) region in south China. By attributing all NH3 emissions in the tunnel to light-duty gasoline vehicles, we obtained a fuel-based emission rate of 2.92 ± 0.18 g L-1 and a mileage-based emission factor of 229.5 ± 14.1 mg km-1. These emission factors were much higher than those measured in the United States while measured NO x emission factors (7.17 ± 0.60 g L-1 or 0.56 ± 0.05 g km-1) were contrastingly near or lower than those previously estimated by MOBILE/PART5 or COPERT IV models. Based on the NH3 emission factors from this study, on-road vehicles accounted for 8.1% of NH3 emissions in the PRD region in 2006 instead of 2.5% as estimated in a previous study using emission factors taken from the Emission Inventory Improvement Program (EIIP) in the United States.

Emission factor of ammonia (NH3) from on-road vehicles in China: tunnel tests in urban Guangzhou

International Nuclear Information System (INIS)

Liu, Tengyu; Wang, Xinming; Ding, Xiang; Deng, Wei; Lü, Sujun; Zhang, Yanli; Wang, Boguang

2014-01-01

Ammonia (NH 3 ) is the primary alkaline gas in the atmosphere that contributes to formation of secondary particles. Emission of NH 3 from vehicles, particularly gasoline powered light duty vehicles equipped with three-way catalysts, is regarded as an important source apart from emissions from animal wastes and soils, yet measured emission factors for motor vehicles are still not available in China, where traffic-related emission has become an increasingly important source of air pollutants in urban areas. Here we present our tunnel tests for NH 3 from motor vehicles under ‘real world conditions’ in an urban roadway tunnel in Guangzhou, a central city in the Pearl River Delta (PRD) region in south China. By attributing all NH 3 emissions in the tunnel to light-duty gasoline vehicles, we obtained a fuel-based emission rate of 2.92 ± 0.18 g L −1 and a mileage-based emission factor of 229.5 ± 14.1 mg km −1 . These emission factors were much higher than those measured in the United States while measured NO x emission factors (7.17 ± 0.60 g L −1 or 0.56 ± 0.05 g km −1 ) were contrastingly near or lower than those previously estimated by MOBILE/PART5 or COPERT IV models. Based on the NH 3 emission factors from this study, on-road vehicles accounted for 8.1% of NH 3 emissions in the PRD region in 2006 instead of 2.5% as estimated in a previous study using emission factors taken from the Emission Inventory Improvement Program (EIIP) in the United States. (letter)

Novel method for on-road emission factor measurements using a plume capture trailer.

Science.gov (United States)

Morawska, L; Ristovski, Z D; Johnson, G R; Jayaratne, E R; Mengersen, K

2007-01-15

The method outlined provides for emission factor measurements to be made for unmodified vehicles driving under real world conditions at minimal cost. The method consists of a plume capture trailer towed behind a test vehicle. The trailer collects a sample of the naturally diluted plume in a 200 L conductive bag and this is delivered immediately to a mobile laboratory for subsequent analysis of particulate and gaseous emissions. The method offers low test turnaround times with the potential to complete much larger numbers of emission factor measurements than have been possible using dynamometer testing. Samples can be collected at distances up to 3 m from the exhaust pipe allowing investigation of early dilution processes. Particle size distribution measurements, as well as particle number and mass emission factor measurements, based on naturally diluted plumes are presented. A dilution profile relating the plume dilution ratio to distance from the vehicle tail pipe for a diesel passenger vehicle is also presented. Such profiles are an essential input for new mechanistic roadway air quality models.

Explanatory factors of CO2 per capita emission inequality in the European Union

International Nuclear Information System (INIS)

Padilla, Emilio; Duro, Juan Antonio

2013-01-01

The design of European mitigation policies requires a detailed examination of the factors explaining the unequal emissions in the different countries. This research analyzes the evolution of inequality in CO 2 emissions per capita in the European Union (EU-27) in the period 1990–2009 and its explanatory factors. For this purpose, we decompose the Theil index of inequality into the contributions of the different Kaya factors. The decomposition is also applied to the inequality between and within groups of countries (North Europe, South Europe, and East Europe). The analysis shows an important reduction in inequality, to a large extent due to the smaller differences between groups and because of the lower contribution of the energy intensity factor. The importance of the GDP per capita factor increases and becomes the main explanatory factor. However, within the different groups of countries the carbonization index appears to be the most relevant factor in explaining inequalities. The policy implications of the results are discussed. - Highlights: • CO 2 inequality in EU-27 (Theil index) is decomposed into explanatory (Kaya) factors. • It decreases more between than within regions (North, South, East). • Energy intensity contribution falls and turns negative. GDP pc becomes main factor. • Carbonization makes most relevant contribution to inequality within groups. • Policy implications on feasibility of agreements and mitigation policy are discussed

Vehicle emission factors of solid nanoparticles in the laboratory and on the road using Portable Emission Measurement Systems (PEMS

Directory of Open Access Journals (Sweden)

Barouch eGiechaskiel

2015-12-01

Full Text Available Emission inventories are used to quantify sources and identify trends in the emissions of air pollutants. They use vehicle-specific emission factors that are typically determined in the laboratory, through remote-sensing, vehicle chasing experiments and, more recently, on-board Portable Emission Measurement Systems (PEMS. Although PEMS is widely applied to measure gaseous pollutants, their application to Solid Particle Number (SPN emissions is new. In this paper, we discuss the current status of determining SPN emission factors both on the chassis dynamometer and on-road using PEMS-SPN. First, we determine the influence of the measurement equipment, ambient temperature, driving style and cycle characteristics, and the extra mass of the PEMS equipment on the SPN emissions. Afterward, we present the SPN emissions under type-approval conditions as well as on the road of two heavy-duty diesel vehicles equipped with Diesel Particulate Filter (DPF (one Euro VI, two light-duty diesel vehicles equipped with DPF, one light-duty vehicle equipped with a Port Fuel Injection engine (PFI, and seven Gasoline Direct Injection (GDI passenger cars (two Euro 6. We find that cold-start and strong accelerations tend to substantially increase SPN emissions. The two heavy-duty vehicles showed emissions around 2×10^13 p/km (Euro V truck and 6×10^10 p/km (Euro VI truck, respectively. One of the DPF-equipped light-duty vehicles showed emissions of 8×10^11 p/km, while the other one had one order of magnitude lower emissions. The PFI car had SPN emissions slightly higher than 1×10^12 p/km. The emissions of GDI cars spanned approximately from 8×10^11 p/km to 8×10^12 p/km. For the cars without DPF, the SPN emissions remained within a factor of two of the laboratory results. This factor was on average around 0.8 for the Euro 6 and 1.6 for the Euro 5 GDIs. The DPF equipped vehicles showed a difference of almost one order of magnitude between laboratory and on-road tests

Integral emission factors for methane determined using urban flux measurements and local-scale inverse models

Science.gov (United States)

Christen, Andreas; Johnson, Mark; Molodovskaya, Marina; Ketler, Rick; Nesic, Zoran; Crawford, Ben; Giometto, Marco; van der Laan, Mike

2013-04-01

The most important long-lived greenhouse gas (LLGHG) emitted during combustion of fuels is carbon dioxide (CO2), however also traces of the LLGHGs methane (CH4) and nitrous oxide (N2O) are released, the quantities of which depend largely on the conditions of the combustion process. Emission factors determine the mass of LLGHGs emitted per energy used (or kilometre driven for cars) and are key inputs for bottom-up emission modelling. Emission factors for CH4 are typically determined in the laboratory or on a test stand for a given combustion system using a small number of samples (vehicles, furnaces), yet associated with larger uncertainties when scaled to entire fleets. We propose an alternative, different approach - Can integrated emission factors be independently determined using direct micrometeorological flux measurements over an urban surface? If so, do emission factors determined from flux measurements (top-down) agree with up-scaled emission factors of relevant combustion systems (heating, vehicles) in the source area of the flux measurement? Direct flux measurements of CH4 were carried out between February and May, 2012 over a relatively densely populated, urban surface in Vancouver, Canada by means of eddy covariance (EC). The EC-system consisted of an ultrasonic anemometer (CSAT-3, Campbell Scientific Inc.) and two open-path infrared gas analyzers (Li7500 and Li7700, Licor Inc.) on a tower at 30m above the surface. The source area of the EC system is characterised by a relative homogeneous morphometry (5.3m average building height), but spatially and temporally varying emission sources, including two major intersecting arterial roads (70.000 cars drive through the 50% source area per day) and seasonal heating in predominantly single-family houses (natural gas). An inverse dispersion model (turbulent source area model), validated against large eddy simulations (LES) of the urban roughness sublayer, allows the determination of the spatial area that

Trend Prediction and Decomposed Driving Factors of Carbon Emissions in Jiangsu Province during 2015–2020

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Decai Tang

2016-10-01

Full Text Available According to the economic and energy consumption statistics in Jiangsu Province, we combined the GM (1, 1 grey model and polynomial regression to forecast carbon emissions. Historical and projected emissions were decomposed using the Logarithmic Mean Divisia Index (LMDI approach to assess the relative contribution of different factors to emission variability. The results showed that carbon emissions will continue to increase in Jiangsu province during 2015–2020 period and cumulative carbon emissions will increase by 39.5487 million tons within the forecast period. The growth of gross domestic product (GDP per capita plays the greatest positive role in driving carbon emission growth. Furthermore, the improvement of energy usage efficiency is the primary factor responsible for reducing carbon emissions. Factors of population, industry structure adjustment and the optimization of fuel mix also help to reduce carbon emissions. Based on the LMDI analysis, we provide some advice for policy-makers in Jiangsu and other provinces in China.

Real-time emission factor measurements of isocyanic acid from light duty gasoline vehicles.

Science.gov (United States)

Brady, James M; Crisp, Timia A; Collier, Sonya; Kuwayama, Toshihiro; Forestieri, Sara D; Perraud, Véronique; Zhang, Qi; Kleeman, Michael J; Cappa, Christopher D; Bertram, Timothy H

2014-10-07

Exposure to gas-phase isocyanic acid (HNCO) has been previously shown to be associated with the development of atherosclerosis, cataracts and rheumatoid arthritis. As such, accurate emission inventories for HNCO are critical for modeling the spatial and temporal distribution of HNCO on a regional and global scale. To date, HNCO emission rates from light duty gasoline vehicles, operated under driving conditions, have not been determined. Here, we present the first measurements of real-time emission factors of isocyanic acid from a fleet of eight light duty gasoline-powered vehicles (LDGVs) tested on a chassis dynamometer using the Unified Driving Cycle (UC) at the California Air Resources Board (CARB) Haagen-Smit test facility, all of which were equipped with three-way catalytic converters. HNCO emissions were observed from all vehicles, in contrast to the idealized laboratory measurements. We report the tested fleet averaged HNCO emission factors, which depend strongly on the phase of the drive cycle; ranging from 0.46 ± 0.13 mg kg fuel(-1) during engine start to 1.70 ± 1.77 mg kg fuel(-1) during hard acceleration after the engine and catalytic converter were warm. The tested eight-car fleet average fuel based HNCO emission factor was 0.91 ± 0.58 mg kg fuel(-1), within the range previously estimated for light duty diesel-powered vehicles (0.21-3.96 mg kg fuel(-1)). Our results suggest that HNCO emissions from LDGVs represent a significant emission source in urban areas that should be accounted for in global and regional models.

Revised methane emissions factors and spatially distributed annual carbon fluxes for global livestock

Science.gov (United States)

Livestock play an important role in carbon cycling through consumption of biomass and emissions of methane. Recent research suggests that existing bottom-up inventories of livestock methane emissions in the U.S., such as those made using 2006 IPCC Tier 1 livestock emissions factors, are too low. Thi...

Transport sector CO2 emissions growth in Asia: Underlying factors and policy options

International Nuclear Information System (INIS)

Timilsina, Govinda R.; Shrestha, Ashish

2009-01-01

This study analyze the potential factors influencing the growth of transport sector carbon dioxide (CO 2 ) emissions in selected Asian countries during the 1980-2005 period by decomposing annual emissions growth into components representing changes in fuel mix, modal shift, per capita gross domestic product (GDP) and population, as well as changes in emission coefficients and transportation energy intensity. We find that changes in per capita GDP, population growth and transportation energy intensity are the main factors driving transport sector CO 2 emission growth in the countries considered. While growth in per capita income and population are responsible for the increasing trend of transport sector CO 2 emissions in China, India, Indonesia, Republic of Korea, Malaysia, Pakistan, Sri Lanka and Thailand; the decline of transportation energy intensity is driving CO 2 emissions down in Mongolia. Per capita GDP, population and transportation energy intensity effects are all found responsible for transport sector CO 2 emissions growth in Bangladesh, the Philippines and Vietnam. The study also reviews existing government policies to limit CO 2 emissions growth, such as fiscal instruments, fuel economy standards and policies to encourage switching to less emission intensive fuels and transportation modes.

Improving and disaggregating N_2O emission factors for ruminant excreta on temperate pasture soils

International Nuclear Information System (INIS)

Krol, D.J.; Carolan, R.; Minet, E.; McGeough, K.L.; Watson, C.J.; Forrestal, P.J.; Lanigan, G.J.; Richards, K.G.

2016-01-01

Cattle excreta deposited on grazed grasslands are a major source of the greenhouse gas (GHG) nitrous oxide (N_2O). Currently, many countries use the IPCC default emission factor (EF) of 2% to estimate excreta-derived N_2O emissions. However, emissions can vary greatly depending on the type of excreta (dung or urine), soil type and timing of application. Therefore three experiments were conducted to quantify excreta-derived N_2O emissions and their associated EFs, and to assess the effect of soil type, season of application and type of excreta on the magnitude of losses. Cattle dung, urine and artificial urine treatments were applied in spring, summer and autumn to three temperate grassland sites with varying soil and weather conditions. Nitrous oxide emissions were measured from the three experiments over 12 months to generate annual N_2O emission factors. The EFs from urine treated soil was greater (0.30–4.81% for real urine and 0.13–3.82% for synthetic urine) when compared with dung (− 0.02–1.48%) treatments. Nitrous oxide emissions were driven by environmental conditions and could be predicted by rainfall and temperature before, and soil moisture deficit after application; highlighting the potential for a decision support tool to reduce N_2O emissions by modifying grazing management based on these parameters. Emission factors varied seasonally with the highest EFs in autumn and were also dependent on soil type, with the lowest EFs observed from well-drained and the highest from imperfectly drained soil. The EFs averaged 0.31 and 1.18% for cattle dung and urine, respectively, both of which were considerably lower than the IPCC default value of 2%. These results support both lowering and disaggregating EFs by excreta type. - Highlights: • N_2O emissions were measured from cattle excreta applied to pasture. • N_2O was universally higher from urine compared with dung. • N_2O was driven by rainfall, temperature and soil moisture deficit. • Emission

Characterization of emission factors related to source activity for trichloroethylene degreasing and chrome plating processes.

Science.gov (United States)

Wadden, R A; Hawkins, J L; Scheff, P A; Franke, J E

1991-09-01

A study at an automotive parts fabrication plant evaluated four metal surface treatment processes during production conditions. The evaluation provides examples of how to estimate process emission factors from activity and air concentration data. The processes were open tank and enclosed tank degreasing with trichloroethylene (TCE), chromium conversion coating, and chromium electroplating. Area concentrations of TCE and chromium (Cr) were monitored for 1-hr periods at three distances from each process. Source activities at each process were recorded during each sampling interval. Emission rates were determined by applying appropriate mass balance models to the concentration patterns around each source. The emission factors obtained from regression analysis of the emission rate and activity data were 16.9 g TCE/basket of parts for the open-top degreaser; 1.0 g TCE/1000 parts for the enclosed degreaser; 1.48-1.64 mg Cr/1000 parts processed in the hot CrO3/HNO3 tank for the chrome conversion coating; and 5.35-9.17 mg Cr/rack of parts for chrome electroplating. The factors were also used to determine the efficiency of collection for the local exhaust systems serving each process. Although the number of observations were limited, these factors may be useful for providing initial estimates of emissions from similar processes in other settings.

The emission factor of volatile isoprenoids: stress, acclimation, and developmental responses

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Ü. Niinemets

2010-07-01

Full Text Available The rate of constitutive isoprenoid emissions from plants is driven by plant emission capacity under specified environmental conditions (E_S, the emission factor and by responsiveness of the emissions to instantaneous variations in environment. In models of isoprenoid emission, E_S has been often considered as intrinsic species-specific constant invariable in time and space. Here we analyze the variations in species-specific values of E_S under field conditions focusing on abiotic stresses, past environmental conditions and developmental processes. The reviewed studies highlight strong stress-driven, adaptive (previous temperature and light environment and growth CO₂ concentration and developmental (leaf age variations in E_S values operating at medium to long time scales. These biological factors can alter species-specific E_S values by more than an order of magnitude. While the majority of models based on early concepts still ignore these important sources of variation, recent models are including some of the medium- to long-term controls. However, conceptually different strategies are being used for incorporation of these longer-term controls with important practical implications for parameterization and application of these models. This analysis emphasizes the need to include more biological realism in the isoprenoid emission models and also highlights the gaps in knowledge that require further experimental work to reduce the model uncertainties associated with biological sources of variation.

How the user can influence particulate emissions from residential wood and pellet stoves: Emission factors for different fuels and burning conditions

Science.gov (United States)

Fachinger, Friederike; Drewnick, Frank; Gieré, Reto; Borrmann, Stephan

2017-06-01

For a common household wood stove and a pellet stove we investigated the dependence of emission factors for various gaseous and particulate pollutants on burning phase, burning condition, and fuel. Ideal and non-ideal burning conditions (dried wood, under- and overload, small logs, logs with bark, excess air) were used. We tested 11 hardwood species (apple, ash, bangkirai, birch, beech, cherry, hickory, oak, olive, plum, sugar maple), 4 softwood species (Douglas fir, pine, spruce, spruce/fir), treated softwood, beech and oak wood briquettes, paper briquettes, brown coal, wood chips, and herbaceous species (miscanthus, Chinese silver grass) as fuel. Particle composition (black carbon, non-refractory, and some semi-refractory species) was measured continuously. Repeatability was shown to be better for the pellet stove than for the wood stove. It was shown that the user has a strong influence on wood stove emission behavior both by selection of the fuel and of the burning conditions: Combustion efficiency was found to be low at both very low and very high burn rates, and influenced particle properties such as particle number, mass, and organic content in a complex way. No marked differences were found for the emissions from different wood species. For non-woody fuels, much higher emission factors could be observed (up to five-fold increase). Strongest enhancement of emission factors was found for burning of small or dried logs (up to six-fold), and usage of excess air (two- to three-fold). Real world pellet stove emissions can be expected to be much closer to laboratory-derived emission factors than wood stove emissions, due to lower dependence on user operation.

International inequalities in per capita CO2 emissions: a decomposition methodology by Kaya factors

International Nuclear Information System (INIS)

Duro, J.A.; Universitat de Barcelona; Padilla, E.

2006-01-01

In this paper, we provide a methodology for decomposing international inequalities in per capita CO 2 emissions into Kaya (multiplicative) factors and two interaction terms. We use the Theil index of inequality and show that this decomposition methodology can be extended for analyzing between- and within-group inequality components. We can thus analyze the factors behind inequalities in per capita CO 2 emissions across countries, between groups of countries and within groups of countries. The empirical illustration for international data suggests some points. Firstly, international inequality in per capita CO 2 emissions is mainly attributable to inequalities in per capita income levels, which helps to explain its recent reduction, while differences in carbon intensity of energy and energy intensity have made a less significant contribution. This result is strongly influenced by the performance of China and India. Secondly, the between-group inequality component, which is the biggest component, is also largely explained by the income factor. Thirdly, the within-group inequality component increased slightly during the period, something mainly due to the change in the income factor and the interaction terms in a few regions. (author)

Quantification of variability and uncertainty in lawn and garden equipment NOx and total hydrocarbon emission factors.

Science.gov (United States)

Frey, H Christopher; Bammi, Sachin

2002-04-01

Variability refers to real differences in emissions among multiple emission sources at any given time or over time for any individual emission source. Variability in emissions can be attributed to variation in fuel or feedstock composition, ambient temperature, design, maintenance, or operation. Uncertainty refers to lack of knowledge regarding the true value of emissions. Sources of uncertainty include small sample sizes, bias or imprecision in measurements, nonrepresentativeness, or lack of data. Quantitative methods for characterizing both variability and uncertainty are demonstrated and applied to case studies of emission factors for lawn and garden (L&G) equipment engines. Variability was quantified using empirical and parametric distributions. Bootstrap simulation was used to characterize confidence intervals for the fitted distributions. The 95% confidence intervals for the mean grams per brake horsepower/hour (g/hp-hr) emission factors for two-stroke engine total hydrocarbon (THC) and NOx emissions were from -30 to +41% and from -45 to +75%, respectively. The confidence intervals for four-stroke engines were from -33 to +46% for THCs and from -27 to +35% for NOx. These quantitative measures of uncertainty convey information regarding the quality of the emission factors and serve as a basis for calculation of uncertainty in emission inventories (EIs).

The influencing factors of CO2 emission intensity of Chinese agriculture from 1997 to 2014.

Science.gov (United States)

Long, Xingle; Luo, Yusen; Wu, Chao; Zhang, Jijian

2018-05-01

In China, agriculture produces the greatest chemical oxygen demand (COD) emissions in wastewater and the most methane (CH 4 ) emissions. It is imperative that agricultural pollution in China be reduced. This study investigated the influencing factors of the CO 2 emission intensity of Chinese agriculture from 1997 to 2014. We analyzed the influencing factors of the CO 2 emission intensity through the first-stage least-square regression. We also analyzed determinants of innovation through the second-stage least-square regression. We found that innovation negatively affected the CO 2 emission intensity in the model of the nation. FDI positively affected innovation in China. It is important to enhance indigenous innovation for green agriculture through labor training and collaboration between agriculture and academia.

Emission factors of greenhouse gases from layer and broiler barns in Cameroon

Science.gov (United States)

Ngwabie, N. Martin; Acobta, Ada N.; Manga, Veronica E.; VanderZaag, Andrew C.

2018-03-01

Limited information is available in the literature on greenhouse gas (GHG) quantification from livestock production systems in Africa. Therefore, this project was carried out to generate baseline emission factors of methane (CH4), nitrous oxide (N2O) and carbon dioxide (CO2) from broiler and layer barns with building design typical of Cameroon. Emissions were measured from two broiler barns during the entire production cycles and a layer barn for a limited period using flux chambers. Methane emission factors from the broiler barns with mud and cement floors were 0.96 ± 1.04 and 0.36 ± 0.17 mg bird-1 hr-1 respectively, and 0.76 ± 0.56 mg bird-1 hr-1 from the layer barn with cement floor. Nitrous oxide emission from the broiler barns with mud and cement floors were 12.94 ± 10.11 and 1.68 ± 1.02 mg bird-1 hr-1 respectively, and 0.21 ± 0.28 mg bird-1 hr-1 from the layer barn. Carbon dioxide emission factors from the broiler barns with mud and cement floors were 9327 ± 3508 and 25526 ± 6904 mg bird-1 hr-1 respectively, and 8942 ± 36756 mg bird-1 hr-1 from the layer barn. When scaled per livestock unit (LU), where 1 LU is 500 kg bird weight, CH4 emissions were 0.16 ± 0.17 and 0.06 ± 0.03 g LU-1 hr-1 from the broiler barns, and 0.19 ± 0.14 g LU-1 hr-1 from the layer barn. Nitrous oxide emissions were 2.16 ± 1.69 and 0.28 ± 0.17 g LU-1 hr-1 from the broiler barns, and 0.05 ± 0.07 g LU-1 hr-1 from the layer barn. Broilers reared in management systems with wood shavings on mud floor had relatively high CH4 and N2O emissions compared to broilers on wood shavings and cement floor, with the contrary observed for CO2. The emissions N2O were significantly higher from broiler barns compared to layer barns. Emissions were higher in the mornings compared to later periods of the day. Given the observed results, GHG emission mitigation strategies need to be customised for each building design and management system.

Determination of OB/OD/SF Emission Factors Using Unmanned Aerial Systems

Science.gov (United States)

A presentation to the Demilitarization Symposium. This proposal will present the methods of tethered aerostat and unmanned aerial system for collection of plume samples and determination of emission factors form open burning, open detonation, and static firing for weapon demilita...

Evaluation of life-cycle air emission factors of freight transportation.

Science.gov (United States)

Facanha, Cristiano; Horvath, Arpad

2007-10-15

Life-cycle air emission factors associated with road, rail, and air transportation of freight in the United States are analyzed. All life-cycle phases of vehicles, infrastructure, and fuels are accounted for in a hybrid life-cycle assessment (LCA). It includes not only fuel combustion, but also emissions from vehicle manufacturing, maintenance, and end of life, infrastructure construction, operation, maintenance, and end of life, and petroleum exploration, refining, and fuel distribution. Results indicate that total life-cycle emissions of freight transportation modes are underestimated if only tailpipe emissions are accounted for. In the case of CO2 and NOx, tailpipe emissions underestimate total emissions by up to 38%, depending on the mode. Total life-cycle emissions of CO and SO2 are up to seven times higher than tailpipe emissions. Sensitivity analysis considers the effects of vehicle type, geography, and mode efficiency on the final results. Policy implications of this analysis are also discussed. For example, while it is widely assumed that currently proposed regulations will result in substantial reductions in emissions, we find that this is true for NOx, emissions, because fuel combustion is the main cause, and to a lesser extent for SO2, but not for PM10 emissions, which are significantly affected by the other life-cycle phases.

Seasonal Variation and Ecosystem Dependence of Emission Factors for Selected Trace Gases and PM2.5 for Southern African Savanna Fires

Science.gov (United States)

Korontzi, S.; Ward, D. E.; Susott, R. A.; Yokelson, R. J.; Justice, C. O.; Hobbs, P. V.; Smithwick, E. A. H.; Hao, W. M.

2003-01-01

In this paper we present the first early dry season (early June-early August) emission factor measurements for carbon dioxide (CO2), carbon monoxide (CO), methane (Ca), nonmethane hydrocarbons (NMHC), and particulates with a diameter less than 2.5 microns (pM2.5) for southern African grassland and woodland fires. Seasonal emission factors for grassland fires correlate linearly with the proportion of green grass, used as a surrogate for the fuel moisture content, and are higher for products of incomplete combustion in the early part of the dry season compared with later in the dry season. Models of emission factors for NMHC and PM(sub 2.5) versus modified combustion efficiency (MCE) are statistically different in grassland compared with woodland ecosystems. We compare predictions based on the integration of emissions factors from this study, from the southern African Fire-Atmosphere Research Initiative 1992 (SAFARI-92), and from SAFARI-2000 with those based on the smaller set of ecosystem-specific emission factors to estimate the effects of using regional-average rather than ecosystem-specific emission factors. We also test the validity of using the SAFARI-92 models for emission factors versus MCE to predict the early dry season emission factors measured in this study. The comparison indicates that the largest discrepancies occur at the low end (0.907) and high end (0.972) of MCE values measured in this study. Finally, we combine our models of MCE versus proportion of green grass for grassland fires with emission factors versus MCE for selected oxygenated volatile organic compounds measured in the SAFARI-2000 campaign to derive the first seasonal emission factors for these compounds. The results of this study demonstrate that seasonal variations in savanna fire emissions are important and should be considered in modeling emissions at regional to continental scales.

NOx emission calculations for bulk carriers by using engine power probabilities as weighting factors.

Science.gov (United States)

Cheng, Chih-Wen; Hua, Jian; Hwang, Daw-Shang

2017-10-01

An important marine pollution issue identified by the International Maritime Organization (IMO) is NO x emissions; however, the stipulated method for determining the NO x certification value does not reflect the actual high emission factors of slow-speed two-stroke diesel engines over long-term slow steaming. In this study, an accurate method is presented for calculating the NO x emission factors and total amount of NO x emissions by using the actual power probabilities of the diesel engines in four types of bulk carriers. The proposed method is suitable for all types and purposes of diesel engines, is not restricted to any operating modes, and is highly accurate. Moreover, it is recommended that the IMO-stipulated certification value calculation method be modified accordingly to genuinely reduce the amount of NO x emissions. The successful achievement of this level of reduction will help improve the air quality, especially in coastal and port areas, and the health of local residents. As per the IMO, the NO x emission certification value of marine diesel engines having a rated power over 130 kW must be obtained using specified weighting factor (WF)-based calculation. However, this calculation fails to represent the current actual situation. Effective emission reductions of 6.91% (at sea) and 31.9% (in ports) were achieved using a mathematical model of power probability functions. Thus, we strongly recommend amending the certification value of NO x Technical Code 2008 (NTC 2008) by removing the WF constraints, such that the NO x emissions of diesel engines is lower than the Tier-limits at any load level to obtain genuine NO x emission reductions.

Research on carbon emission driving factors of China’s provincial construction industry

Science.gov (United States)

Shang, Mei; Dong, Rui; Fu, Yujie; Hao, Wentao

2018-03-01

As a pillar industry of the national economy, the damage to the environment by construction industry can not be ignored. In the context of low carbon development, identifying the main driving factors for the carbon emission of the provincial construction industry are the key for the local government to formulate the development strategy for construction. In the paper, based on the Kaya factor decomposition method, the carbon intensity of the energy structure, energy intensity and the impact of the construction output on the carbon emission of provincial construction industry are studied, and relevant suggestions for low carbon development of provincial construction industry are proposed. The conclusion of this paper provides a theoretical basis for the early realization of low-carbon development in China’s provincial construction industry.

Improving and disaggregating N{sub 2}O emission factors for ruminant excreta on temperate pasture soils

Energy Technology Data Exchange (ETDEWEB)

Krol, D.J., E-mail: kroldj@tcd.ie [Teagasc, Crops, Land Use and Environment Programme, Johnstown Castle, Co., Wexford (Ireland); Carolan, R. [Agri-Food and Biosciences Institute (AFBI), Belfast BT9 5PX (Ireland); Minet, E. [Teagasc, Crops, Land Use and Environment Programme, Johnstown Castle, Co., Wexford (Ireland); McGeough, K.L.; Watson, C.J. [Agri-Food and Biosciences Institute (AFBI), Belfast BT9 5PX (Ireland); Forrestal, P.J. [Teagasc, Crops, Land Use and Environment Programme, Johnstown Castle, Co., Wexford (Ireland); Lanigan, G.J., E-mail: gary.lanigan@teagasc.ie [Teagasc, Crops, Land Use and Environment Programme, Johnstown Castle, Co., Wexford (Ireland); Richards, K.G. [Teagasc, Crops, Land Use and Environment Programme, Johnstown Castle, Co., Wexford (Ireland)

2016-10-15

Cattle excreta deposited on grazed grasslands are a major source of the greenhouse gas (GHG) nitrous oxide (N{sub 2}O). Currently, many countries use the IPCC default emission factor (EF) of 2% to estimate excreta-derived N{sub 2}O emissions. However, emissions can vary greatly depending on the type of excreta (dung or urine), soil type and timing of application. Therefore three experiments were conducted to quantify excreta-derived N{sub 2}O emissions and their associated EFs, and to assess the effect of soil type, season of application and type of excreta on the magnitude of losses. Cattle dung, urine and artificial urine treatments were applied in spring, summer and autumn to three temperate grassland sites with varying soil and weather conditions. Nitrous oxide emissions were measured from the three experiments over 12 months to generate annual N{sub 2}O emission factors. The EFs from urine treated soil was greater (0.30–4.81% for real urine and 0.13–3.82% for synthetic urine) when compared with dung (− 0.02–1.48%) treatments. Nitrous oxide emissions were driven by environmental conditions and could be predicted by rainfall and temperature before, and soil moisture deficit after application; highlighting the potential for a decision support tool to reduce N{sub 2}O emissions by modifying grazing management based on these parameters. Emission factors varied seasonally with the highest EFs in autumn and were also dependent on soil type, with the lowest EFs observed from well-drained and the highest from imperfectly drained soil. The EFs averaged 0.31 and 1.18% for cattle dung and urine, respectively, both of which were considerably lower than the IPCC default value of 2%. These results support both lowering and disaggregating EFs by excreta type. - Highlights: • N{sub 2}O emissions were measured from cattle excreta applied to pasture. • N{sub 2}O was universally higher from urine compared with dung. • N{sub 2}O was driven by rainfall, temperature

Consideration of Real World Factors Influencing Greenhouse Gas Emissions in ALPHA

Science.gov (United States)

Discuss a variety of factors that influence the simulated fuel economy and GHG emissions that are often overlooked and updates made to ALPHA based on actual benchmarking data observed across a range of vehicles and transmissions. ALPHA model calibration is also examined, focusin...

Emission Factors of Selected Organic Compounds from Domestic Hardwood Combustion

Czech Academy of Sciences Publication Activity Database

Hopan, F.; Šyc, Michal; Horák, J.; Dej, M.; Krpec, K.; Ocelka, T.; Tomšej, T.; Pekárek, Vladimír

LVI, č. 3 (2009), s. 81-85 ISSN 1210-0471 R&D Projects: GA MŽP(CZ) SP/1A2/116/07; GA MŠk 2B08048 Institutional research plan: CEZ:AV0Z40720504 Keywords : wood * small sources * emission factors Subject RIV: DI - Air Pollution ; Quality http://transactions.fs.vsb.cz/2009-3/12hop.pdf

GHG emission factors developed for the collection, transport and landfilling of municipal waste in South African municipalities

Energy Technology Data Exchange (ETDEWEB)

Friedrich, Elena, E-mail: Friedriche@ukzn.ac.za [CRECHE Centre for Research in Environmental, Coastal and Hydrological Engineering, School of Engineering, Civil Engineering Programme, University of KwaZulu-Natal, Howard College Campus, Durban (South Africa); Trois, Cristina [CRECHE Centre for Research in Environmental, Coastal and Hydrological Engineering, School of Engineering, Civil Engineering Programme, University of KwaZulu-Natal, Howard College Campus, Durban (South Africa)

2013-04-15

Highlights: ► An average GHG emission factor for the collection and transport of municipal solid waste in South Africa is calculated. ► A range of GHG emission factors for different types of landfills (including dumps) in South Africa are calculated. ► These factors are compared internationally and their implications for South Africa and developing countries are discussed . ► Areas for new research are highlighted. - Abstract: Greenhouse gas (GHG) emission factors are used with increased frequency for the accounting and reporting of GHG from waste management. However, these factors have been calculated for developed countries of the Northern Hemisphere and are lacking for developing countries. This paper shows how such factors have been developed for the collection, transport and landfilling of municipal waste in South Africa. As such it presents a model on how international results and methodology can be adapted and used to calculate country-specific GHG emission factors from waste. For the collection and transport of municipal waste in South Africa, the average diesel consumption is around 5 dm{sup 3} (litres) per tonne of wet waste and the associated GHG emissions are about 15 kg CO{sub 2} equivalents (CO{sub 2} e). Depending on the type of landfill, the GHG emissions from the landfilling of waste have been calculated to range from −145 to 1016 kg CO{sub 2} e per tonne of wet waste, when taking into account carbon storage, and from 441 to 2532 kg CO{sub 2} e per tonne of wet waste, when carbon storage is left out. The highest emission factor per unit of wet waste is for landfill sites without landfill gas collection and these are the dominant waste disposal facilities in South Africa. However, cash strapped municipalities in Africa and the developing world will not be able to significantly upgrade these sites and reduce their GHG burdens if there is no equivalent replacement of the Clean Development Mechanism (CDM) resulting from the Kyoto agreement

On-road assessment of light duty vehicles in Delhi city: Emission factors of CO, CO2 and NOX

Science.gov (United States)

Jaiprakash; Habib, Gazala

2018-02-01

This study presents the technology based emission factors of gaseous pollutants (CO, CO2, and NOX) measured during on-road operation of nine passenger cars of diesel, gasoline, and compressed natural gas (CNG). The emissions from two 3-wheelers, and three 2-wheelers were measured by putting the vehicles on jacks and operating them according to Modified Indian Driving Cycle (MIDC) at no load condition. The emission factors observed in the present work were significantly higher than values reported from dynamometer study by Automotive Research Association of India (ARAI). Low CO (0.34 ± 0.08 g km-1) and high NOX (1.0 ± 0.4 g km-1) emission factors were observed for diesel passenger cars, oppositely high CO (2.2 ± 2.6 g km-1) and low NOX (1.0 ± 1.6 g km-1) emission factors were seen for gasoline powered cars. The after-treatment technology in diesel vehicles was effective in CO reduction. While the use of turbocharger in diesel vehicles to generate high combustion temperature and pressure produces more NOx, probably which may not be effectively controlled by after-treatment device. The after-treatment devices in gasoline powered Post-2010, Post-2005 vehicles can be acclaimed for reduced CO emissions compared to Post-2000 vehicles. This work presents a limited data set of emission factors from on-road operations of light duty vehicles, this limitation can be improved by further measurements of emissions from similar vehicles.

Direct nitrous oxide emissions in Mediterranean climate cropping systems : Emission factors based on a meta-analysis of available measurement data

NARCIS (Netherlands)

Cayuela, Maria L.; Aguilera, Eduardo; Sanz-Cobena, Alberto; Adams, Dean C.; Abalos, Diego; Barton, Louise; Ryals, Rebecca; Silver, Whendee L.; Alfaro, Marta A.; Pappa, Valentini A.; Smith, Pete; Garnier, Josette; Billen, Gilles; Bouwman, Lex; Bondeau, Alberte; Lassaletta, Luis

2017-01-01

Many recent reviews and meta-analyses of N2O emissions do not include data from Mediterranean studies. In this paper we present a meta-analysis of the N2O emissions from Mediterranean cropping systems, and propose a more robust and reliable regional emission factor (EF) for N2O, distinguishing the

Geographical Detector Model for Influencing Factors of Industrial Sector Carbon Dioxide Emissions in Inner Mongolia, China

Directory of Open Access Journals (Sweden)

Rina Wu

2016-02-01

Full Text Available Studying the influencing factors of carbon dioxide emissions is not only practically but also theoretically crucial for establishing regional carbon-reduction policies, developing low-carbon economy and solving the climate problems. Therefore, we used a geographical detector model which is consists of four parts, i.e., risk detector, factor detector, ecological detector and interaction detector to analyze the effect of these social economic factors, i.e., GDP, industrial structure, urbanization rate, economic growth rate, population and road density on the increase of energy consumption carbon dioxide emissions in industrial sector in Inner Mongolia northeast of China. Thus, combining with the result of four detectors, we found that GDP and population more influence than economic growth rate, industrial structure, urbanization rate and road density. The interactive effect of any two influencing factors enhances the increase of the carbon dioxide emissions. The findings of this research have significant policy implications for regions like Inner Mongolia.

Analysis of Grid Emission Factors for the Electricity Sector in Caribbean Countries

DEFF Research Database (Denmark)

Hinostroza, Miriam L.; Desgain, Denis DR; Perez Martín, David

by undertaking a study to calculate standardized grid emissionfactors (GEF) for sixteen independent nations or groups of countries in the Caribbean region as a basis to the further identification of mitigation activities such as CDM PoAs or any other market-related instrument to be approved by the UNFCCC......As part of their capacity development efforts to promote mitigation actions, the UNEP DTU Partnership, together with the UNFCCC Regional Collaborating Centre in the Caribbean, UNDP and OLADE, agreed to collaborate with Caribbean countries willing to update or establish their grid emission factors...... emission factor for countries with generation units with similar characteristics. Data on the power systems of the different countries have been collected from several centres and institutions, including the UNEP DTU Partnership, the Latin American Energy Organization (OLADE), the Caribbean Community...

Transport sector CO{sub 2} emissions growth in Asia: Underlying factors and policy options

Energy Technology Data Exchange (ETDEWEB)

Timilsina, Govinda R., E-mail: gtimilsina@worldbank.or [Development Research Group, World Bank, 1818H Street, NW, Washington, DC 20433 (United States); Shrestha, Ashish [Development Research Group, World Bank, 1818H Street, NW, Washington, DC 20433 (United States)

2009-11-15

This study analyze the potential factors influencing the growth of transport sector carbon dioxide (CO{sub 2}) emissions in selected Asian countries during the 1980-2005 period by decomposing annual emissions growth into components representing changes in fuel mix, modal shift, per capita gross domestic product (GDP) and population, as well as changes in emission coefficients and transportation energy intensity. We find that changes in per capita GDP, population growth and transportation energy intensity are the main factors driving transport sector CO{sub 2} emission growth in the countries considered. While growth in per capita income and population are responsible for the increasing trend of transport sector CO{sub 2} emissions in China, India, Indonesia, Republic of Korea, Malaysia, Pakistan, Sri Lanka and Thailand; the decline of transportation energy intensity is driving CO{sub 2} emissions down in Mongolia. Per capita GDP, population and transportation energy intensity effects are all found responsible for transport sector CO{sub 2} emissions growth in Bangladesh, the Philippines and Vietnam. The study also reviews existing government policies to limit CO{sub 2} emissions growth, such as fiscal instruments, fuel economy standards and policies to encourage switching to less emission intensive fuels and transportation modes.

Transport sector CO{sub 2} emissions growth in Asia. Underlying factors and policy options

Energy Technology Data Exchange (ETDEWEB)

Timilsina, Govinda R.; Shrestha, Ashish [Development Research Group, The World Bank, 1818H Street, NW, Washington, DC 20433 (United States)

2009-11-15

This study analyze the potential factors influencing the growth of transport sector carbon dioxide (CO{sub 2}) emissions in selected Asian countries during the 1980-2005 period by decomposing annual emissions growth into components representing changes in fuel mix, modal shift, per capita gross domestic product (GDP) and population, as well as changes in emission coefficients and transportation energy intensity. We find that changes in per capita GDP, population growth and transportation energy intensity are the main factors driving transport sector CO{sub 2} emission growth in the countries considered. While growth in per capita income and population are responsible for the increasing trend of transport sector CO{sub 2} emissions in China, India, Indonesia, Republic of Korea, Malaysia, Pakistan, Sri Lanka and Thailand; the decline of transportation energy intensity is driving CO{sub 2} emissions down in Mongolia. Per capita GDP, population and transportation energy intensity effects are all found responsible for transport sector CO{sub 2} emissions growth in Bangladesh, the Philippines and Vietnam. The study also reviews existing government policies to limit CO{sub 2} emissions growth, such as fiscal instruments, fuel economy standards and policies to encourage switching to less emission intensive fuels and transportation modes. (author)

N2O emission hotspots at different spatial scales and governing factors for small scale hotspots

International Nuclear Information System (INIS)

Heuvel, R.N. van den; Hefting, M.M.; Tan, N.C.G.; Jetten, M.S.M.; Verhoeven, J.T.A.

2009-01-01

Chronically nitrate-loaded riparian buffer zones show high N 2 O emissions. Often, a large part of the N 2 O is emitted from small surface areas, resulting in high spatial variability in these buffer zones. These small surface areas with high N 2 O emissions (hotspots) need to be investigated to generate knowledge on the factors governing N 2 O emissions. In this study the N 2 O emission variability was investigated at different spatial scales. Therefore N 2 O emissions from three 32 m 2 grids were determined in summer and winter. Spatial variation and total emission were determined on three different scales (0.3 m 2 , 0.018 m 2 and 0.0013 m 2 ) at plots with different levels of N 2 O emissions. Spatial variation was high at all scales determined and highest at the smallest scale. To test possible factors inducing small scale hotspots, soil samples were collected for slurry incubation to determine responses to increased electron donor/acceptor availability. Acetate addition did increase N 2 O production, but nitrate addition failed to increase total denitrification or net N 2 O production. N 2 O production was similar in all soil slurries, independent of their origin from high or low emission soils, indicating that environmental conditions (including physical factors like gas diffusion) rather than microbial community composition governed N 2 O emission rates

Emission factors of polybrominated diphenyl ethers (PBDEs) from plastics processing and recycling facilities

Energy Technology Data Exchange (ETDEWEB)

Sakai, Shin-ichi; Hirai, Yasuhiro [National Institute for Environmental Studies, Tsukuba (Japan); Ota, Shizuko; Sudo, Kinichi [Ministry of Environment (Japan)

2004-09-15

With regard to polybrominated diphenyl ether (PBDE), there is few scientific knowledge on the emission patterns into the environment and exposure pathways to humans, and basic information is insufficient to consider what measures effective are. For the purpose of promoting risk reduction of target substances more effectively and efficiently, it is desirable to comprehend accurately the causal chain from the target substances utilization to the risk intake, and to evaluate the measures covering the whole applications of target substances. As the existing researches on the PBDE emission inventory, there are EU risk assessment report (European Chemical Bureau 2000, 2002, 2003), Danish EPA (1999), Palm et al.(2002) and Alcock et al. (2003). In addition, emissions of DecaBDE are published in TRI (Toxic Release Inventory) of US EPA. However, the primary information of the previous inventories is often the same and estimations based on the measured values are few. In light of the situation, PBDE emission concentrations from processing facilities of flame retardant plastics and recycling facilities of home electric appliances are measured in practice to presume material flow of PBDE and to estimate emission factors and inventories from each phase of life cycles. The validities of emission factors are examined in comparison to measured values of atmospheric depositions surroundings, which are close to sources.

Development of a life-cycle fugitive methane emissions model utilizing device level emissions and activity factors

Science.gov (United States)

Englander, J.; Brandt, A. R.

2017-12-01

There has been numerous studies in quantifying the scale of fugitive emissions from across the natural gas value chain. These studies have typically focused on either specific types of equipment (such as valves) or on a single part of the life-cycle of natural gas production (such as gathering stations).1,2 However it has been demonstrated that average emissions factors are not sufficient for representing leaks in the natural gas system.3 In this work, we develop a robust estimate of fugitive emissions rates by incorporating all publicly available studies done at the component up to the process level. From these known studies, we create a database of leaks with normalized nomenclature from which leak estimates can be drawn from actual leak observations. From this database, and parameterized by meta-data such as location, scale of study, or placement in the life-cycle, we construct stochastic emissions factors specific for each process unit. This will be an integrated tool as part of the Oil production greenhouse gas estimator (OPGEE) as well as the Fugitive Emissions Abatement Simulation Toolkit (FEAST) models to enhances their treatment of venting and fugitive emissions, and will be flexible to include user provided data and input parameters.4,51. Thoma, ED et al. Assessment of Uinta Basin Oil and Natural Gas Well Pad Pneumatic Controller Emissions. J. Environ. Prot. 2017. 2. Marchese, AJ et al. Methane Emissions from United States Natural Gas Gathering and Processing. ES&T 2015. doi:10.1021/acs.est.5b02275 3. Brandt, AR et al. Methane Leaks from Natural Gas Systems Follow Extreme Distributions. ES&T 2016. doi:10.1021/acs.est.6b04303 4. El-Houjeiri, HM et al. An open-source LCA tool estimating greenhouse gas emissions from crude oil production using field characteristics. ES&T 2013. doi: 10.1021/es304570m 5. Kemp, CE et al. Comparing Natural Gas Leakage Detection Technologies Using an Open-Source `Virtual Gas Field' Simulator. ES&T 2016. doi:10.1021/acs.est.5b

Surface-plasmon-induced modification on the spontaneous emission spectrum via subwavelength-confined anisotropic Purcell factor.

Science.gov (United States)

Gu, Ying; Wang, Luojia; Ren, Pan; Zhang, Junxiang; Zhang, Tiancai; Martin, Olivier J F; Gong, Qihuang

2012-05-09

The mechanism of using the anisotropic Purcell factor to control the spontaneous emission linewidths in a four-level atom is theoretically demonstrated; if the polarization angle bisector of the two dipole moments lies along the axis of large/small Purcell factor, destructive/constructive interference narrows/widens the fluorescence center spectral lines. Large anisotropy of the Purcell factor, confined in the subwavelength optical mode volume, leads to rapid spectral line narrowing of atom approaching a metallic nanowire, nanoscale line width pulsing following periodically varying decay rates near a periodic metallic nanostructure, and dramatic modification on the spontaneous emission spectrum near a custom-designed resonant plasmon nanostructure. The combined system opens a good perspective for applications in ultracompact active quantum devices.

Measurements of air pollution emission factors for marine transportation in SECA

NARCIS (Netherlands)

Alföldy, B.; Lööv, J.; Lagler, F.; Mellqvist, J.; Berg, N.; Beecken, J.; Weststrate, J.H.; Duyzer, J.H.; Bencs, L.; Horemans, B.; Cavalli, F.; Putaud, J.P.; Janssens-Maenhout, G.; Csordas, A.P.; Grieken, R. van; Borowiak, A.; Hjorth, J.

2013-01-01

The chemical composition of the plumes of seagoing ships was measured during a two week long measure- ment campaign in the port of Rotterdam, Hoek van Holland The Netherlands, in September 2009. Altogether, 497 ships were monitored and a statistical evaluation of emission factors (g kg−1 fuel) was

International inequalities in per capita CO{sub 2} emissions: a decomposition methodology by Kaya factors

Energy Technology Data Exchange (ETDEWEB)

Duro, J.A. [Universitat Rovira i Virgili, Reus (Spain). Dept. d' Economia; Universitat de Barcelona (Spain). Inst. de Analisis Economico; Padilla, E. [Universitat de Barcelona (Spain). Dept. d' Economia Aplicada

2006-03-15

In this paper, we provide a methodology for decomposing international inequalities in per capita CO{sub 2} emissions into Kaya (multiplicative) factors and two interaction terms. We use the Theil index of inequality and show that this decomposition methodology can be extended for analyzing between- and within-group inequality components. We can thus analyze the factors behind inequalities in per capita CO{sub 2} emissions across countries, between groups of countries and within groups of countries. The empirical illustration for international data suggests some points. Firstly, international inequality in per capita CO{sub 2} emissions is mainly attributable to inequalities in per capita income levels, which helps to explain its recent reduction, while differences in carbon intensity of energy and energy intensity have made a less significant contribution. This result is strongly influenced by the performance of China and India. Secondly, the between-group inequality component, which is the biggest component, is also largely explained by the income factor. Thirdly, the within-group inequality component increased slightly during the period, something mainly due to the change in the income factor and the interaction terms in a few regions. (author)

Updated greenhouse gas and criteria air pollutant emission factors and their probability distribution functions for electricity generating units

International Nuclear Information System (INIS)

Cai, H.; Wang, M.; Elgowainy, A.; Han, J.

2012-01-01

Greenhouse gas (CO 2 , CH 4 and N 2 O, hereinafter GHG) and criteria air pollutant (CO, NO x , VOC, PM 10 , PM 2.5 and SO x , hereinafter CAP) emission factors for various types of power plants burning various fuels with different technologies are important upstream parameters for estimating life-cycle emissions associated with alternative vehicle/fuel systems in the transportation sector, especially electric vehicles. The emission factors are typically expressed in grams of GHG or CAP per kWh of electricity generated by a specific power generation technology. This document describes our approach for updating and expanding GHG and CAP emission factors in the GREET (Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation) model developed at Argonne National Laboratory (see Wang 1999 and the GREET website at http://greet.es.anl.gov/main) for various power generation technologies. These GHG and CAP emissions are used to estimate the impact of electricity use by stationary and transportation applications on their fuel-cycle emissions. The electricity generation mixes and the fuel shares attributable to various combustion technologies at the national, regional and state levels are also updated in this document. The energy conversion efficiencies of electric generating units (EGUs) by fuel type and combustion technology are calculated on the basis of the lower heating values of each fuel, to be consistent with the basis used in GREET for transportation fuels. On the basis of the updated GHG and CAP emission factors and energy efficiencies of EGUs, the probability distribution functions (PDFs), which are functions that describe the relative likelihood for the emission factors and energy efficiencies as random variables to take on a given value by the integral of their own probability distributions, are updated using best-fit statistical curves to characterize the uncertainties associated with GHG and CAP emissions in life-cycle modeling with GREET.

Spatial estimation of air PM2.5 emissions using activity data, local emission factors and land cover derived from satellite imagery

Science.gov (United States)

Gibe, Hezron P.; Cayetano, Mylene G.

2017-09-01

Exposure to particulate matter (PM) is a serious environmental problem in many urban areas on Earth. In the Philippines, most existing studies and emission inventories have mainly focused on point and mobile sources, while research involving human exposures to particulate pollutants is rare. This paper presents a method for estimating the amount of fine particulate (PM2.5) emissions in a test study site in the city of Cabanatuan, Nueva Ecija, in the Philippines, by utilizing local emission factors, regionally procured data, and land cover/land use (activity data) interpreted from satellite imagery. Geographic information system (GIS) software was used to map the estimated emissions in the study area. The present results suggest that vehicular emissions from motorcycles and tricycles, as well as fuels used by households (charcoal) and burning of agricultural waste, largely contribute to PM2.5 emissions in Cabanatuan. Overall, the method used in this study can be applied in other small urbanizing cities, as long as on-site specific activity, emission factor, and satellite-imaged land cover data are available.

Forecasting Energy-Related CO2 Emissions Employing a Novel SSA-LSSVM Model: Considering Structural Factors in China

Directory of Open Access Journals (Sweden)

Huiru Zhao

2018-03-01

Full Text Available Carbon dioxide (CO2 emissions forecasting is becoming more important due to increasing climatic problems, which contributes to developing scientific climate policies and making reasonable energy plans. Considering that the influential factors of CO2 emissions are multiplex and the relationships between factors and CO2 emissions are complex and non-linear, a novel CO2 forecasting model called SSA-LSSVM, which utilizes the Salp Swarm Algorithm (SSA to optimize the two parameters of the least squares support sector machine (LSSVM model, is proposed in this paper. The influential factors of CO2 emissions, including the gross domestic product (GDP, population, energy consumption, economic structure, energy structure, urbanization rate, and energy intensity, are regarded as the input variables of the SSA-LSSVM model. The proposed model is verified to show a better forecasting performance compared with the selected models, including the single LSSVM model, the LSSVM model optimized by the particle swarm optimization algorithm (PSO-LSSVM, and the back propagation (BP neural network model, on CO2 emissions in China from 2014 to 2016. The comparative analysis indicates the SSA-LSSVM model is greatly superior and has the potential to improve the accuracy and reliability of CO2 emissions forecasting. CO2 emissions in China from 2017 to 2020 are forecast combined with the 13th Five-Year Plan for social, economic and energy development. The comparison of CO2 emissions of China in 2020 shows that structural factors significantly affect CO2 emission forecasting results. The average annual growth of CO2 emissions slows down significantly due to a series of policies and actions taken by the Chinese government, which means China can keep the promise that greenhouse gas emissions will start to drop after 2030.

Quantification of vehicle fleet PM_1_0 particulate matter emission factors from exhaust and non-exhaust sources using tunnel measurement techniques

International Nuclear Information System (INIS)

Lawrence, Samantha; Sokhi, Ranjeet; Ravindra, Khaiwal

2016-01-01

Road tunnels act like large laboratories; they provide an excellent environment to quantify atmospheric particles emission factors from exhaust and non-exhaust sources due to their known boundary conditions. Current work compares the High Volume, Dichotomous Stacked Filter Unit and Partisol Air Sampler for coarse, PM_1_0 and PM_2_._5 particle concentration measurement and found that they do not differ significantly (p = 95%). PM_2_._5 fraction contributes 66% of PM_1_0 proportions and significantly influenced by traffic (turbulence) and meteorological conditions. Mass emission factors for PM_1_0 varies from 21.3 ± 1.9 to 28.8 ± 3.4 mg/vkm and composed of Motorcycle (0.0003–0.001 mg/vkm), Cars (26.1–33.4 mg/vkm), LDVs (2.4–3.0 mg/vkm), HDVs (2.2–2.8 mg/vkm) and Buses (0.1 mg/vkm). Based on Lawrence et al. (2013), source apportionment modelling, the PM_1_0 emission of brake wear (3.8–4.4 mg/vkm), petrol exhaust (3.9–4.5 mg/vkm), diesel exhaust (7.2–8.3 mg/vkm), re-suspension (9–10.4 mg/vkm), road surface wear (3.9–4.5 mg/vkm), and unexplained (7.2 mg/vkm) were also calculated. The current study determined that the combined non-exhaust fleet PM_1_0 emission factor (16.7–19.3 mg/vkm) are higher than the combined exhaust emission factor (11.1–12.8 mg/vkm). Thus, highlight the significance of non-exhaust emissions and the need for legislation and abatement strategies to reduce their contributions to ambient PM concentrations. - Highlights: • Calculations of exhaust/non-exhaust particulate emission factors using tunnel sampling and source apportionment techniques. • Non-exhaust emission dominates in the fine particle fraction, considered responsible for adverse human health impacts. • Emission factors for non-exhaust sources (e.g. tyre and brake) were calculated. • Fleet source PM_1_0 emission factor were also calculated, which can be used in dispersion modelling and health risk assessment. • Tukey mean

Urban Household Carbon Emission and Contributing Factors in the Yangtze River Delta, China

Science.gov (United States)

Xu, Xibao; Tan, Yan; Chen, Shuang; Yang, Guishan; Su, Weizhong

2015-01-01

Carbon reduction at the household level is an integral part of carbon mitigation. This study analyses the characteristics, effects, contributing factors and policies for urban household carbon emissions in the Yangtze River Delta of China. Primary data was collected through structured questionnaire surveys in three cities in the region – Nanjing, Ningbo, and Changzhou in 2011. The survey data was first used to estimate the magnitude of household carbon emissions in different urban contexts. It then examined how, and to what extent, each set of demographic, economic, behavioral/cognitive and spatial factors influence carbon emissions at the household level. The average of urban household carbon emissions in the region was estimated to be 5.96 tonnes CO2 in 2010. Energy consumption, daily commuting, garbage disposal and long-distance travel accounted for 51.2%, 21.3%, 16.0% and 11.5% of the total emission, respectively. Regulating rapidly growing car-holdings of urban households, stabilizing population growth, and transiting residents’ low-carbon awareness to household behavior in energy saving and other spheres of consumption in the context of rapid population aging and the growing middle income class are suggested as critical measures for carbon mitigation among urban households in the Yangtze River Delta. PMID:25884853

Emission factor ratios, SOA mass yields, and the impact of vehicular emissions on SOA formation

Science.gov (United States)

Ensberg, J. J.; Hayes, P. L.; Jimenez, J. L.; Gilman, J. B.; Kuster, W. C.; de Gouw, J. A.; Holloway, J. S.; Gordon, T. D.; Jathar, S.; Robinson, A. L.; Seinfeld, J. H.

2014-03-01

The underprediction of ambient secondary organic aerosol (SOA) levels by current atmospheric models in urban areas is well established, yet the cause of this underprediction remains elusive. Likewise, the relative contribution of emissions from gasoline- and diesel-fueled vehicles to the formation of SOA is generally unresolved. We investigate the source of these two discrepancies using data from the 2010 CalNex experiment carried out in the Los Angeles Basin (Ryerson et al., 2013). Specifically, we use gas-phase organic mass (GPOM) and CO emission factors in conjunction with measured enhancements in oxygenated organic aerosol (OOA) relative to CO to quantify the significant lack of closure between expected and observed organic aerosol concentrations attributable to fossil-fuel emissions. Two possible conclusions emerge from the analysis to yield consistency with the ambient data: (1) vehicular emissions are not a dominant source of anthropogenic fossil SOA in the Los Angeles Basin, or (2) the ambient SOA mass yields used to determine the SOA formation potential of vehicular emissions are substantially higher than those derived from laboratory chamber studies.

Influencing Factors of Companies’ Behavior for Mitigation: A Discussion within the Context of Emission Trading Scheme

Directory of Open Access Journals (Sweden)

Yidan Chen

2018-02-01

Full Text Available China built pilot carbon emission trading schemes in seven regions and established a national carbon trading market in electricity sector in December 2017. This study conducted a questionnaire survey of 570 companies in 29 regions nationwide and found that companies still need to improve mitigation measures regarding fossil fuel combustion, production technology, output adjustment and environmental management. By establishing regression models, influencing factors of carbon emission reduction are identified. Pilot emission trading policy has a significant impact on company emission reduction behaviors. Companies inside or outside the pilot region respond differently to the influencing factors. Companies inside emphasize more on energy price and mitigation potential, while enterprises outside pay more attention to investment and familiarity with technology and policy.

A Factor Decomposition on China’s Carbon Emission from 1997 to 2012 Based on IPAT-LMDI Model

Directory of Open Access Journals (Sweden)

Wei Li

2015-01-01

Full Text Available We probe into the key factors that possess significant effects on China’s CO2 emissions during 1997–2012 on the basis of IPAT-LMDI model. Carbon dioxide emissions are specifically decomposed into CO2 emission intensity, energy structure, energy intensity, industrial structure, economic output, and population scale effects. Results indicate that the paramount driving factors that resulted in the growth of CO2 emissions are economic output, population scale, and energy structure. In contrast, energy intensity and industrial structure generally play an outstanding role in reducing emissions. This paper constructs a new weight assessment system by introducing “contribution value-significant factor-effect coefficient” to replace “contribution value-contribution rate” in the previous literature. According to the most significant positive effect and the most negative effect from the conclusion, we point out the effective policies that can not only accelerate the target of “China’s carbon emissions per unit of GDP could be cut down by 40–45% by 2020, from 2005 levels,” but also have crucial significance on the low-carbon economic development strategy of China.

An empirical research on the influencing factors of regional CO2 emissions: Evidence from Beijing city, China

International Nuclear Information System (INIS)

Wang, Zhaohua; Yin, Fangchao; Zhang, Yixiang; Zhang, Xian

2012-01-01

Highlights: ► We adapt STIRPAT model to regional context and conduct PLS regress analysis. ► Energy technology related patent is innovatively used to measure technical factors. ► Urbanization level has the greatest interpretative ability for CO 2 emissions. ► We do not find evidence of Environmental Kuznets Curve in Beijing. ► Beijing should focus more on tertiary industry and residential energy consumption. -- Abstract: In order to further study the realization of carbon intensity target, find the key influencing factors of CO 2 emissions, and explore the path of developing low-carbon economy, this paper empirically studied the influences of urbanization level, economic level, industry proportion, tertiary industry proportion, energy intensity and R and D output on CO 2 emissions in Beijing using improved STIRPAT (stochastic impacts by regression on population, affluence and technology) model. The model is examined using partial least square regression. Results show that urbanization level, economic level and industry proportion positively influence the CO 2 emissions, while tertiary industry proportion, energy intensity and R and D output negatively do. Urbanization level is the main driving factor of CO 2 emissions, and tertiary industry proportion is the main inhibiting factor. In addition, along with the growth of per capita GDP, the increase of CO 2 emissions does not follow the Environmental Kuznets Curve model. Based on these empirical findings and the specific circumstances of Beijing, we provide some policy recommendations on how to reduce carbon intensity. Beijing should pay more attention to tertiary industry and residential energy consumption for carbon emission reduction. It is necessary to establish a comprehensive evaluation index of social development. Investing more capital on carbon emission reduction science and technology, and promoting R and D output is also an efficient way to reduce CO 2 emissions.

Factors affecting CO2 emission from the power sector of selected countries in Asia and the Pacific

International Nuclear Information System (INIS)

Shrestha, Ram M.; Anandarajah, Gabrial; Liyanage, Migara H.

2009-01-01

This study analyzes the key factors behind the CO 2 emissions from the power sector in fifteen selected countries in Asia and the Pacific using the Log-Mean Divisia Index method of decomposition. The roles of changes in economic output, electricity intensity of the economy, fuel intensity of power generation and generation structure are examined in the evolution of CO 2 emission from the power sector of the selected countries during 1980-2004. The study shows that the economic growth was the dominant factor behind the increase in CO 2 emission in ten of the selected countries (i.e., Australia, China, India, Japan, Malaysia, Pakistan, South Korea, Singapore, Thailand and Vietnam, while the increasing electricity intensity of the economy was the main factor in three countries (Bangladesh, Indonesia and Philippines). Structural changes in power generation were found to be the main contributor to changes in the CO 2 emission in the case of Sri Lanka and New Zealand.

An empirical study on the institutional factors of energy conservation and emissions reduction: Evidence from listed companies in China

International Nuclear Information System (INIS)

Zhang, Zhaoguo; Jin, Xiaocui; Yang, Qingxiang; Zhang, Yi

2013-01-01

Corporate excessive energy consumption and emissions are negative externality problems, with the basic countermeasure of establishing a series of institutional programs to promote corporate energy conservation and emissions reduction. This paper analyzes the influence of institutional factors such as laws, tax policies, credit policies, government subsidies, media supervision and marketization degree on corporate energy conservation and emissions reduction from the institutional perspective. The data, from 84 listed Chinese chemical and steel companies from 2006 to 2010, was analyzed using both a fixed effect model and the generalized method of moments (GMM) model. The empirical results demonstrate that these institutional factors positively affect corporate energy conservation and emissions reduction. Specifically, four factors – tax policies, government subsidies, credit policies and media supervision – have a significant positive relationship with corporate energy conservation and emissions reduction; whereas laws and marketization degree exhibit no significant effects. The research findings are theoretically and practically significant to the Chinese government with regard to improving the institutional environment and promoting corporate energy conservation and emissions reduction. - Highlights: ► Theoretical analysis of the influence of institutional factors based on NIE. ► Empirical analysis of the influence of institutional factors on ECER by regression. ► Economic measures and public opinions have positive influence on ECER in China. ► Laws and the degree of marketization have weak influence on ECER in China

Emission factors of black carbon and co-pollutants from diesel vehicles in Mexico City

Science.gov (United States)

Zavala, Miguel; Molina, Luisa T.; Yacovitch, Tara I.; Fortner, Edward C.; Roscioli, Joseph R.; Floerchinger, Cody; Herndon, Scott C.; Kolb, Charles E.; Knighton, Walter B.; Paramo, Victor Hugo; Zirath, Sergio; Mejía, José Antonio; Jazcilevich, Aron

2017-12-01

Diesel-powered vehicles are intensively used in urban areas for transporting goods and people but can substantially contribute to high emissions of black carbon (BC), organic carbon (OC), and other gaseous pollutants. Strategies aimed at controlling mobile emissions sources thus have the potential to improve air quality and help mitigate the impacts of air pollutants on climate, ecosystems, and human health. However, in developing countries there are limited data on the BC and OC emission characteristics of diesel-powered vehicles, and thus there are large uncertainties in the estimation of the emission contributions from these sources. We measured BC, OC, and other inorganic components of fine particulate matter (PM), as well as carbon monoxide (CO), nitrogen oxides (NOx), sulfur dioxide (SO2), ethane, acetylene, benzene, toluene, and C2-benzenes under real-world driving conditions for 20 diesel-powered vehicles encompassing multiple emission level technologies in Mexico City with the chasing technique using the Aerodyne mobile laboratory. Average BC emission factors ranged from 0.41-2.48 g kg-1 of fuel depending on vehicle type. The vehicles were also simultaneously measured using the cross-road remote sensing technique to obtain the emission factors of nitrogen oxide (NO), CO, total hydrocarbons, and fine PM, thus allowing for the intercomparison of the results from the two techniques. There is overall good agreement between the two techniques and both can identify high and low emitters, but substantial differences were found in some of the vehicles, probably due to the ability of the chasing technique to capture a larger diversity of driving conditions in comparison to the remote sensing technique. A comparison of the results with the US EPA MOVES2014b model showed that the model underestimates CO, OC, and selected VOC species, whereas there is better agreement for NOx and BC. Larger OC / BC ratios were found in comparison to ratios measured in California using

Emission factors of black carbon and co-pollutants from diesel vehicles in Mexico City

Directory of Open Access Journals (Sweden)

M. Zavala

2017-12-01

Full Text Available Diesel-powered vehicles are intensively used in urban areas for transporting goods and people but can substantially contribute to high emissions of black carbon (BC, organic carbon (OC, and other gaseous pollutants. Strategies aimed at controlling mobile emissions sources thus have the potential to improve air quality and help mitigate the impacts of air pollutants on climate, ecosystems, and human health. However, in developing countries there are limited data on the BC and OC emission characteristics of diesel-powered vehicles, and thus there are large uncertainties in the estimation of the emission contributions from these sources. We measured BC, OC, and other inorganic components of fine particulate matter (PM, as well as carbon monoxide (CO, nitrogen oxides (NOx, sulfur dioxide (SO2, ethane, acetylene, benzene, toluene, and C2-benzenes under real-world driving conditions for 20 diesel-powered vehicles encompassing multiple emission level technologies in Mexico City with the chasing technique using the Aerodyne mobile laboratory. Average BC emission factors ranged from 0.41–2.48 g kg−1 of fuel depending on vehicle type. The vehicles were also simultaneously measured using the cross-road remote sensing technique to obtain the emission factors of nitrogen oxide (NO, CO, total hydrocarbons, and fine PM, thus allowing for the intercomparison of the results from the two techniques. There is overall good agreement between the two techniques and both can identify high and low emitters, but substantial differences were found in some of the vehicles, probably due to the ability of the chasing technique to capture a larger diversity of driving conditions in comparison to the remote sensing technique. A comparison of the results with the US EPA MOVES2014b model showed that the model underestimates CO, OC, and selected VOC species, whereas there is better agreement for NOx and BC. Larger OC / BC ratios were found in comparison to ratios

Updated greenhouse gas and criteria air pollutant emission factors and their probability distribution functions for electricity generating units

Energy Technology Data Exchange (ETDEWEB)

Cai, H.; Wang, M.; Elgowainy, A.; Han, J. (Energy Systems)

2012-07-06

Greenhouse gas (CO{sub 2}, CH{sub 4} and N{sub 2}O, hereinafter GHG) and criteria air pollutant (CO, NO{sub x}, VOC, PM{sub 10}, PM{sub 2.5} and SO{sub x}, hereinafter CAP) emission factors for various types of power plants burning various fuels with different technologies are important upstream parameters for estimating life-cycle emissions associated with alternative vehicle/fuel systems in the transportation sector, especially electric vehicles. The emission factors are typically expressed in grams of GHG or CAP per kWh of electricity generated by a specific power generation technology. This document describes our approach for updating and expanding GHG and CAP emission factors in the GREET (Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation) model developed at Argonne National Laboratory (see Wang 1999 and the GREET website at http://greet.es.anl.gov/main) for various power generation technologies. These GHG and CAP emissions are used to estimate the impact of electricity use by stationary and transportation applications on their fuel-cycle emissions. The electricity generation mixes and the fuel shares attributable to various combustion technologies at the national, regional and state levels are also updated in this document. The energy conversion efficiencies of electric generating units (EGUs) by fuel type and combustion technology are calculated on the basis of the lower heating values of each fuel, to be consistent with the basis used in GREET for transportation fuels. On the basis of the updated GHG and CAP emission factors and energy efficiencies of EGUs, the probability distribution functions (PDFs), which are functions that describe the relative likelihood for the emission factors and energy efficiencies as random variables to take on a given value by the integral of their own probability distributions, are updated using best-fit statistical curves to characterize the uncertainties associated with GHG and CAP emissions in life

Development and review of Euro 5 passenger car emission factors based on experimental results over various driving cycles

OpenAIRE

Fontaras, Georgios; Franco, Vicente; Dilara, Panagiota; Martini, Giorgio; Manfredi, Urbano

2014-01-01

The mass emissions of CO2 and regulated pollutants (NOX, HC, CO, PM) of thirteen Euro 5 compliant passenger cars (seven gasoline, six Diesel) were measured on a chassis dynamometer. The vehicles were driven repeatedly over the European type-approval driving cycle (NEDC) and the more dynamic WMTC and CADC driving cycles. Distance-specific emission factors were derived for each pollutant and sub-cycle which were subsequently compared to the corresponding emission factors provided by the referen...

Magnetic Field Emission Comparison at Different Quality Factors with Series-Parallel Compensation Network for Wireless Power Transfer to Vehicles

DEFF Research Database (Denmark)

Batra, Tushar; Schaltz, Erik

2014-01-01

to the surroundings also increase with increase in the quality factor. In this paper, first analytical expressions are developed for comparing magnetic emissions at different quality factors. Theoretical and simulation (Comsol) results show comparatively lower increase for the magnetic field emissions to the linear...

Decomposition of factors determining the trend of CO{sub 2} emissions from car travel in Great Britain (1970-2000)

Energy Technology Data Exchange (ETDEWEB)

Kwon, Tae-Hyeong [The Korea Transport Institute (KOTI), 2311 Daehwa-dong, Ilsan-gu, Goyang-Shi, Gyeonggi-do, 411-701 (Korea, Republic of)

2005-04-15

Carbon dioxide (CO{sub 2}) is the most important of the greenhouse gases that are causing global warming. The transport sector currently accounts for more than one-quarter of CO{sub 2} emissions and more importantly its share in total emissions is increasing in most countries. This paper investigates the key factors in the change in CO{sub 2} emissions from car travel in Great Britain over the last 30 years. It attempts to disentangle determinants of growth in CO{sub 2} emissions from car travel, which has the largest share of emissions in road transport. The study is based on various decomposition analyses, starting from the IPAT identity. As summarised in the IPAT identity, the degree of the Impact of human activity on the environment is determined by changes in Population, Affluence (per-capita consumption) and Technology (environmental impact per quantity of consumption). In the case of CO{sub 2} emissions from car travel in Great Britain, the affluence (A) factor (car driving distance per person) was a dominant force for the growth of emissions over the last 30 years. Not only do people travel longer distances by cars than 30 years ago, but car occupancy rates have also decreased, contributing to the growth of car driving distance per person. Although technology (T) factors such as fuel efficiency and fuel substitution to diesel fuel partly cancelled out these growth effects of affluence factors, this contribution was relatively small. However, in the 1990s there emerged a different pattern in the trend. Of the affluence (A) factors, the growth rate of car trip distance per person weakened considerably. As for the technology (T) effect, the carbon intensity of car driving kept decreasing over this period. Therefore, although CO{sub 2} emissions from car travel (I) continued to increase, the growth rate became substantially lower than in the earlier periods. More detailed investigation into the determinants of both affluence (A) factors and technology (T

Magnetic field emission comparison at different quality factors with series-series compensation network for inductive power transfer to vehicles

DEFF Research Database (Denmark)

Batra, Tushar; Schaltz, Erik

2014-01-01

Inductive power transfer is non-contact transfer of energy by means of magnetic fields. A higher secondary side quality factor at fixed input current ensures a linear increase in power transfer across the air gap. But also at the same time magnetic emissions to the surroundings increase. First...... of all in this paper an analytic expression for comparing the magnetic emissions at different quality factors is introduced. It is shown with help of simulations on Comsol that emissions have a lower increase as compared to linear increase in the power transferred with the quality factor as suggested...

New estimates of direct N2O emissions from Chinese croplands from 1980 to 2007 using localized emission factors

Directory of Open Access Journals (Sweden)

F. S. Zhang

2011-10-01

Full Text Available Nitrous oxide (N2O is a long-lived greenhouse gas with a large radiation intensity and it is emitted mainly from agricultural land. Accurate estimates of total direct N2O emissions from croplands on a country scale are important for global budgets of anthropogenic sources of N2O emissions and for the development of effective mitigation strategies. The objectives of this study were to re-estimate direct N2O emissions using localized emission factors and a database of measurements from Chinese croplands. We obtained N2O emission factors for paddy fields (0.41 ± 0.04% and uplands (1.05 ± 0.02% from a normalization process through cube root transformation of the original data. After comparing the results of normalization from the original values, Logarithmic and cube root transformations were used because the frequency of the original data was not normally distributed. Direct N2O emissions from Chinese croplands from 1980 to 2007 were estimated using IPCC (2006 guidelines combined with separate localized emission factors for paddy fields and upland areas. Direct N2O emissions from paddy fields showed little change, increasing by 10.5% with an annual rate of increase of 0.4% from 32.3 Gg N2O-N in 1980 to 35.7 Gg N2O-N in 2007. In contrast, emissions from uplands changed dramatically, increasing by 308% with an annual rate of 11% from 68.0 Gg N2O-N in 1980 to 278 Gg N2O-N in 2007. Total direct N2O emissions from Chinese croplands increased by 213% with an annual rate of 7.6% from 100 Gg N2O-N in 1980 to 313 Gg N2O-N in 2007, and were determined mainly by upland emissions (accounting for 67.8–88.6% of total emissions from 1980 to 2007. Synthetic N fertilizers played a major role in N2O emissions from agricultural land, and the magnitude of the contributions to total direct N2O emissions made by different amendments was synthetic N fertilizer > manure > straw, representing about 78, 15, and 6% of total direct N2O emissions, respectively, between

Evaluation of emission factors for light-duty gasoline vehicles based on chassis dynamometer and tunnel studies in Shanghai, China

Science.gov (United States)

Huang, Cheng; Tao, Shikang; Lou, Shengrong; Hu, Qingyao; Wang, Hongli; Wang, Qian; Li, Li; Wang, Hongyu; Liu, Jian'gang; Quan, Yifeng; Zhou, Lanlan

2017-11-01

CO, THC, NOx, and PM emission factors of 51 light-duty gasoline vehicles (LDGVs) spanning the emission standards from Euro 2 to Euro 5 were measured by a chassis dynamometer. High frequencies of high-emitting vehicles were observed in Euro 2 and Euro 3 LDGV fleet. 56% and 33% of high-emitting vehicles contributed 81%-92% and 82%-85% of the emissions in Euro 2 and Euro 3 test fleet, respectively. Malfunctions of catalytic convertors after high strength use are the main cause of the high emissions. Continuous monitoring of a gasoline vehicle dominated tunnel in Shanghai, China was conducted to evaluate the average emission factors of vehicles in real-world. The results indicated that the emission factors of LDGVs were considerably underestimated in EI guidebook in China. The overlook of high-emitting vehicles in older vehicle fleet is the main reason for this underestimation. Enhancing the supervision of high emission vehicles and strengthening the compliance tests of in-use vehicles are essential measures to control the emissions of in-use gasoline vehicles at the present stage in China.

Modelling nitrous oxide emissions from organic and conventional cereal-based cropping systems under different management, soil and climate factors

DEFF Research Database (Denmark)

Doltra, J; Olesen, Jørgen E; Báez, D

2015-01-01

Mitigation of greenhouse gas emissions from agriculture should be assessed across cropping systems and agroclimatic regions. In this study, we investigate the ability of the FASSET model to analyze differences in the magnitude of N2O emissions due to soil, climate and management factors in cereal...... on the seasonal soil N2O fluxes than the environmental factors. Overall, in its current version FASSET reproduced the effects of the different factors investigated on the cumulative seasonal soil N2O emissions but temporally it overestimated emissions from nitrification and denitrification on particular days when...... soil operations, ploughing or fertilization, took place. The errors associated with simulated daily soil N2O fluxes increased with the magnitude of the emissions. For resolving causes of differences in simulated and measured fluxes more intensive and temporally detailed measurements of N2O fluxes...

Effect of Fuels and Domestic Heating Appliance Types on Emission Factors of Selected Organic Pollutants

Czech Academy of Sciences Publication Activity Database

Šyc, Michal; Horák, J.; Hopan, F.; Krpec, K.; Tomšej, T.; Ocelka, T.; Pekárek, Vladimír

2011-01-01

Roč. 45, č. 21 (2011), s. 9427-9434 ISSN 0013-936X R&D Projects: GA MŽP(CZ) SP/1A2/116/07 Institutional research plan: CEZ:AV0Z40720504 Keywords : domestic combustion * PCDD/F * emission factors Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 5.228, year: 2011

Estimation of N2O emission factors for soils depending on environmental conditions and crop management

NARCIS (Netherlands)

Lesschen, J.P.; Velthof, G.L.

2009-01-01

Nitrous oxide (N2O) contributes 8% to anthropogenic global warming, of which about one third are direct emissions of agricultural soils. These N2O emissions are often estimated using the default IPCC 2006 emission factor of 1% of the amount of N applied for mineral fertilizer, manure and crop

Deriving fuel-based emission factor thresholds to interpret heavy-duty vehicle roadside plume measurements.

Science.gov (United States)

Quiros, David C; Smith, Jeremy D; Ham, Walter A; Robertson, William H; Huai, Tao; Ayala, Alberto; Hu, Shaohua

2018-04-13

Remote sensing devices have been used for decades to measure gaseous emissions from individual vehicles at the roadside. Systems have also been developed that entrain diluted exhaust and can also measure particulate matter (PM) emissions. In 2015, the California Air Resources Board (CARB) reported that 8% of in-field diesel particulate filters (DPF) on heavy-duty (HD) vehicles were malfunctioning and emitted about 70% of total diesel PM emissions from the DPF-equipped fleet. A new high-emitter problem in the heavy-duty vehicle fleet had emerged. Roadside exhaust plume measurements reflect a snapshot of real-world operation, typically lasting several seconds. In order to relate roadside plume measurements to laboratory emission tests, we analyzed carbon dioxide (CO 2 ), oxides of nitrogen (NO X ), and PM emissions collected from four HD vehicles during several driving cycles on a chassis dynamometer. We examined the fuel-based emission factors corresponding to possible exceedances of emission standards as a function of vehicle power. Our analysis suggests that a typical HD vehicle will exceed the model year (MY) 2010 emission standards (of 0.2 g NO X /bhp-hr and 0.01 g PM/bhp-hr) by three times when fuel-based emission factors are 9.3 g NO X /kg fuel and 0.11 g PM/kg using the roadside plume measurement approach. Reported limits correspond to 99% confidence levels, which were calculated using the detection uncertainty of emissions analyzers, accuracy of vehicle power calculations, and actual emissions variability of fixed operational parameters. The PM threshold was determined for acceleration events between 0.47 and 1.4 mph/sec only, and the NO X threshold was derived from measurements where aftertreatment temperature was above 200°C. Anticipating a growing interest in real-world driving emissions, widespread implementation of roadside exhaust plume measurements as a compliment to in-use vehicle programs may benefit from expanding this analysis to a larger

Determining residential energy consumption-based CO2 emissions and examining the factors affecting the variation in Ankara, Turkey

Science.gov (United States)

Kus, Melike; Akan, Perihan; Aydinalp Koksal, Merih; Gullu, Gulen

2017-11-01

Energy demand of Turkey has been showing a remarkable increase in the last two decades due to rapid increase in population and changes in consumption trends. In parallel to the increase in energy demand, the CO2 emissions in Turkey are also increasing dramatically due to high usage of fossil fuels. CO2 emissions from the residential sector covers almost one fourth of the total sectoral emissions. In this study, CO2 emissions from the residential sector are estimated, and the factors affecting the emission levels are determined for the residential sector in Ankara, Turkey. In this study, detailed surveys are conducted to more than 400 households in Ankara. Using the information gathered from the surveys, the CO2 emissions associated with energy consumption of the households are calculated using the methodology outlined at IPCC. The statistical analyses are carried out using household income, dwelling characteristics, and household economic and demographic data to determine the factors causing the variation in emission levels among the households. The results of the study present that the main factors impacting the amount of total energy consumption and associated CO2 emissions are household income, dwelling construction year, age, education level of the household, and net footage of the dwelling.

On-line Field Measurements of Speciated PM1 Emission Factors from Common South Asian Combustion Sources

Science.gov (United States)

DeCarlo, P. F.; Goetz, J. D.; Giordano, M.; Stockwell, C.; Maharjan, R.; Adhikari, S.; Bhave, P.; Praveen, P. S.; Panday, A. K.; Jayarathne, T. S.; Stone, E. A.; Yokelson, R. J.

2017-12-01

Characterization of aerosol emissions from prevalent but under sampled combustion sources in South Asia was performed as part of the Nepal Ambient Monitoring and Source Testing Experiment (NAMaSTE) in April 2015. Targeted emission sources included cooking stoves with a variety of solid fuels, brick kilns, garbage burning, crop-residue burning, diesel irrigation pumps, and motorcycles. Real-time measurements of submicron non-refractory particulate mass concentration and composition were obtained using an Aerodyne mini Aerosol Mass Spectrometer (mAMS). Speciated PM1 mass emission factors were calculated for all particulate species (e.g. organics, sulfates, nitrates, chlorides, ammonium) and for each source type using the carbon mass balance approach. Size resolved emission factors were also acquired using a novel high duty cycle particle time-of-flight technique (ePTOF). Black carbon and brown carbon absorption emission factors and absorption Angström exponents were measured using filter loading and scattering corrected attenuation at 370 nm and 880 nm with a dual spot aethalometer (Magee Scientific AE-33). The results indicate that open garbage burning is a strong emitter of organic aerosol, black carbon, and internally mixed particle phase hydrogen chloride (HCl). Emissions of HCl were attributed to the presence chlorinated plastics. The primarily coal fired brick kilns were found to be large emitters of sulfate but large differences in the organic and light absorbing component of emissions were observed between the two kiln types investigated (technologically advanced vs. traditional). These results, among others, bring on-line and field-tested aerosol emission measurements to an area of atmoshperic research dominated by off-line or laboratory based measurements.

Variability in operation-based NO(x) emission factors with different test routes, and its effects on the real-driving emissions of light diesel vehicles.

Science.gov (United States)

Lee, Taewoo; Park, Junhong; Kwon, Sangil; Lee, Jongtae; Kim, Jeongsoo

2013-09-01

The objective of this study is to quantify the differences in NO(x) emissions between standard and non-standard driving and vehicle operating conditions, and to estimate by how much NO(x) emissions exceed the legislative emission limits under typical Korean road traffic conditions. Twelve Euro 3-5 light-duty diesel vehicles (LDDVs) manufactured in Korea were driven on a chassis dynamometer over the standard New European Driving Cycle (NEDC) and a representative Korean on-road driving cycle (KDC). NO(x) emissions, average speeds and accelerations were calculated for each 1-km trip segment, so called averaging windows. The results suggest that the NO(x) emissions of the tested vehicles are more susceptible to variations in the driving cycles than to those in the operating conditions. Even under comparable operating conditions, the NO(x) control capabilities of vehicles differ from each other, i.e., NO(x) control is weaker for the KDC than for the NEDC. The NO(x) emissions over the KDC for given vehicle operating conditions exceed those over the NEDC by more than a factor of 8. Consequently, on-road NO(x) emission factors are estimated here to exceed the Euro 5 emission limit by up to a factor of 8, 4 and 3 for typical Korean urban, rural, and motorway road traffic conditions, respectively. Our findings support the development of technical regulations for supplementary real-world emission tests for emission certification and the corresponding research actions taken by automotive industries. Copyright © 2013 Elsevier B.V. All rights reserved.

Were mercury emission factors for Chinese non-ferrous metal smelters overestimated? Evidence from onsite measurements in six smelters

International Nuclear Information System (INIS)

Zhang Lei; Wang Shuxiao; Wu Qingru; Meng Yang; Yang Hai; Wang Fengyang; Hao Jiming

2012-01-01

Non-ferrous metal smelting takes up a large proportion of the anthropogenic mercury emission inventory in China. Zinc, lead and copper smelting are three leading sources. Onsite measurements of mercury emissions were conducted for six smelters. The mercury emission factors were 0.09–2.98 g Hg/t metal produced. Acid plants with the double-conversion double-absorption process had mercury removal efficiency of over 99%. In the flue gas after acid plants, 45–88% was oxidized mercury which can be easily scavenged in the flue gas scrubber. 70–97% of the mercury was removed from the flue gas to the waste water and 1–17% to the sulfuric acid product. Totally 0.3–13.5% of the mercury in the metal concentrate was emitted to the atmosphere. Therefore, acid plants in non-ferrous metal smelters have significant co-benefit on mercury removal, and the mercury emission factors from Chinese non-ferrous metal smelters were probably overestimated in previous studies. - Highlights: ► Acid plants in smelters provide significant co-benefits for mercury removal (over 99%). ► Most of the mercury in metal concentrates for smelting ended up in waste water. ► Previously published emission factors for Chinese metal smelters were probably overestimated. - Acid plants in smelters have high mercury removal efficiency, and thus mercury emission factors for Chinese non-ferrous metal smelters were probably overestimated.

Emission Characteristics of Gas-Fired Boilers based on Category-Specific Emission Factor from Field Measurements in Beijing, China

Science.gov (United States)

Itahashi, S.; Yan, X.; Song, G.; Yan, J.; Xue, Y.

2017-12-01

Gas-fired boilers will become the main stationary sources of NOx in Beijing. However, the knowledge of gas-fired boilers in Beijing is limited. In the present study, the emission characteristics of NOx, SO2, and CO from gas-fired boilers in Beijing were established using category-specific emission factors (EFs) from field measurements. In order to obtain category-specific EFs, boilers were classified through influence analysis. Factors such as combustion mode, boiler type, and installed capacity were considered critical for establishing EFs because they play significant roles in pollutant formation. The EFs for NOx, CO, and SO2 ranged from 1.42-6.86 g m-3, 0.05-0.67 g m-3 and 0.03-0.48 g m-3. The emissions of NOx, SO2, and CO for gas-fired boilers in Beijing were 11121 t, 468 t, and 222 t in 2014, respectively. The emissions were spatially allocated into grid cells with a resolution of 1 km × 1 km, and the results indicated that top emitters were in central Beijing. The uncertainties were quantified using a Monte Carlo simulation. The results indicated high uncertainties in CO (-157% to 154%) and SO2 (-127% to 182%) emissions, and relatively low uncertainties (-34% to 34%) in NOx emission. Furthermore, approximately 61.2% and 96.8% of the monitored chamber combustion boilers (CCBs) met the standard limits for NOx and SO2, respectively. Concerning NOx, low-NOx burners and NOx emission control measures are urgently needed for implementing of stricter standards. Adopting terminal control measures is unnecessary for SO2, although its concentration occasionally exceeds standard limits, because reduction of its concentration can be achieved thorough control of the sulfur content of natural gas at a stable low level. Furthermore, the atmospheric combustion boilers (ACBs) should be substituted with CCBs, because ACBs have a higher emission despite lower gross installed capacity. The results of this study will enable in understanding and controlling emissions from gas

Real-world emission factors of fine and ultrafine aerosol particles for different traffic situations in Switzerland.

Science.gov (United States)

Imhof, David; Weingartner, Ernest; Ordónez, Carlos; Gehrig, Robert; Hill, Matz; Buchmann, Brigitte; Baltensperger, Urs

2005-11-01

Extended field measurements of particle number (size distribution of particle diameters, D, in the range between 18 nm and 10 microm), surface area concentrations, and PM1 and PM10 mass concentrations were performed in Switzerland to determine traffic emissions using a comprehensive set of instruments. Measurements took place at roads with representative traffic regimes: at the kerbside of a motorway (120 km h(-1)), a highway (80-100 km h(-1)), and in an urban area with stop-and-go traffic (0-50 km h(-1)) regulated by light signals. Mean diurnal variations showed that the highest pollutant concentrations were during the morning rush hours, especially of the number density in the nanoparticle size range (D real-life" emission factors were derived using NOx concentrations to calculate dilution factors. Particle number and volume emission factors of different size ranges (18-50 nm, 18-100 nm, and 18-300 nm) were derived for the total vehicle fleet and separated into a light-duty (LDV) and a heavy-duty vehicle (HDV) contribution. The total particle number emissions per vehicle were found to be about 11.7-13.5 x 10(14) particles km(-1) for constant speed (80-120 km h(-1) and 3.9 x 10(14) particles km(-1) for urban driving conditions. LDVs showed higher emission factors at constant high speed than under urban disturbed traffic flow. In contrast, HDVs emitted more air pollutants during deceleration and acceleration processes in stop-and-go traffic than with constant speed of about 80 km h(-1). On average, one HDV emits a 10-30 times higher amount of particulate air pollutants (in terms of both number and volume) than one LDV.

Emission factors of particulate matter, polycyclic aromatic hydrocarbons, and levoglucosan from wood combustion in south-central Chile.

Science.gov (United States)

Jimenez, Jorge; Farias, Oscar; Quiroz, Roberto; Yañez, Jorge

2017-07-01

In south-central Chile, wood stoves have been identified as an important source of air pollution in populated areas. Eucalyptus (Eucalyptus globulus), Chilean oak (Nothofagus oblique), and mimosa (Acacia dealbata) were burned in a single-chamber slow-combustion wood stove at a controlled testing facility located at the University of Concepción, Chile. In each experiment, 2.7-3.1 kg of firewood were combusted while continuously monitoring temperature, exhaust gases, burn rate, and collecting particulate matter samples in Teflon filters under isokinetic conditions for polycyclic aromatic hydrocarbon and levoglucosan analyses. Mean particulate matter emission factors were 2.03, 4.06, and 3.84 g/kg dry wood for eucalyptus, oak, and mimosa, respectively. The emission factors were inversely correlated with combustion efficiency. The mean emission factors of the sums of 12 polycyclic aromatic hydrocarbons in particle phases were 1472.5, 2134.0, and 747.5 μg/kg for eucalyptus, oak, and mimosa, respectively. Fluoranthene, pyrene, benzo[a]anthracene, and chrysene were present in the particle phase in higher proportions compared with other polycyclic aromatic hydrocarbons that were analyzed. Mean levoglucosan emission factors were 854.9, 202.3, and 328.0 mg/kg for eucalyptus, oak, and mimosa, respectively. Since the emissions of particulate matter and other pollutants were inversely correlated with combustion efficiency, implementing more efficient technologies would help to reduce air pollutant emissions from wood combustion. Residential wood burning has been identified as a significant source of air pollution in populated areas. Local wood species are combusted for home cooking and heating, which releases several toxic air pollutants, including particulate matter, carbon monoxide, and polycyclic aromatic hydrocarbons. Air pollutant emissions depend on the type of wood and the technology and operational conditions of the wood stove. A better understanding of emissions from

Modelling site-specific N2O emission factors from Austrian agricultural soils for targeted mitigation measures (NitroAustria)

Science.gov (United States)

Amon, Barbara; Zechmeister-Boltenstern, Sophie; Kasper, Martina; Foldal, Cecilie; Schiefer, Jasmin; Kitzler, Barbara; Schwarzl, Bettina; Zethner, Gerhard; Anderl, Michael; Sedy, Katrin; Gaugitsch, Helmut; Dersch, Georg; Baumgarten, Andreas; Haas, Edwin; Kiese, Ralf

2016-04-01

Results from a previous project "FarmClim" highlight that the IPCC default emission factor is not able to reflect region specific N2O emissions from Austrian arable soils. The methodology is limited in identifying hot spots and hot moments of N2O emissions. When estimations are based on default emission factors no recommendations can be given on optimisation measures that would lead to a reduction of soil N2O emissions. The better the knowledge is about Nitrogen and Carbon budgets in Austrian agricultural managed soils the better the situation can be reflected in the Austrian GHG emission inventory calculations. Therefore national and regionally modelled emission factors should improve the evidence for national deviation from the IPCC default emission factors and reduce the uncertainties. The overall aim of NitroAustria is to identify the drivers for N2O emissions on a regional basis taking different soil types, climate, and agricultural management into account. We use the LandscapeDNDC model to update the N2O emission factors for N fertilizer and animal manure applied to soils. Key regions in Austria were selected and region specific N2O emissions calculated. The model runs at sub-daily time steps and uses data such as maximum and minimum air temperature, precipitation, radiation, and wind speed as meteorological drivers. Further input data are used to reflect agricultural management practices, e.g., planting/harvesting, tillage, fertilizer application, irrigation and information on soil and vegetation properties for site characterization and model initialization. While at site scale, arable management data (crop cultivation, rotations, timings etc.) is obtained by experimental data from field trials or observations, at regional scale such data need to be generated using region specific proxy data such as land use and management statistics, crop cultivations and yields, crop rotations, fertilizer sales, manure resulting from livestock units etc. The farming

Decomposition Analysis of the Factors that Influence Energy Related Air Pollutant Emission Changes in China Using the SDA Method

Directory of Open Access Journals (Sweden)

Shichun Xu

2017-09-01

Full Text Available We decompose factors affecting China’s energy-related air pollutant (NOx, PM2.5, and SO2 emission changes into different effects using structural decomposition analysis (SDA. We find that, from 2005 to 2012, investment increased NOx, PM2.5, and SO2 emissions by 14.04, 7.82 and 15.59 Mt respectively, and consumption increased these emissions by 11.09, 7.98, and 12.09 Mt respectively. Export and import slightly increased the emissions on the whole, but the rate of the increase has slowed down, possibly reflecting the shift in China’s foreign trade structure. Energy intensity largely reduced NOx, PM2.5, and SO2 emissions by 12.49, 14.33 and 23.06 Mt respectively, followed by emission efficiency that reduces these emissions by 4.57, 9.08, and 17.25 Mt respectively. Input-output efficiency slightly reduces the emissions. At sectoral and sub-sectoral levels, consumption is a great driving factor in agriculture and commerce, whereas investment is a great driving factor in transport, construction, and some industrial subsectors such as iron and steel, nonferrous metals, building materials, coking, and power and heating supply. Energy intensity increases emissions in transport, chemical products and manufacturing, but decreases emissions in all other sectors and subsectors. Some policies arising from our study results are discussed.

Development of Hot Exhaust Emission Factors for Iranian-Made Euro-2 Certified Light-Duty Vehicles.

Science.gov (United States)

Banitalebi, Ehsan; Hosseini, Vahid

2016-01-05

Emission factors (EFs) are fundamental, necessary data for air pollution research and scenario implementation. With the vision of generating national EFs of the Iranian transportation system, a portable emission measurement system (PEMS) was used to develop the basic EFs for a statistically significant sample of Iranian gasoline-fueled privately owned light duty vehicles (LDVs) operated in Tehran. A smaller sample size of the same fleet was examined by chassis dynamometer (CD) bag emission measurement tests to quantify the systematic differences between the PEMS and CD methods. The selected fleet was tested over four different routes of uphill highways, flat highways, uphill urban streets, and flat urban streets. Real driving emissions (RDEs) and fuel consumption (FC) rates were calculated by weighted averaging of the results from each route. The activity of the fleet over each route type was assumed as a weighting factor. The activity data were obtained from a Tehran traffic model. The RDEs of the selected fleet were considerably higher than the certified emission levels of all vehicles. Differences between Tehran real driving cycles and the New European Driving Cycle (NEDC) was attributed to the lower loading of NEDC. A table of EFs based on RDEs was developed for the sample fleet.

Analyzing impact factors of CO2 emissions using the STIRPAT model

International Nuclear Information System (INIS)

Fan Ying; Liu Lancui; Wu Gang; Wei Yiming

2006-01-01

Using the STIRPAT model, this paper analyzes the impact of population, affluence and technology on the total CO 2 emissions of countries at different income levels over the period 1975-2000. Our main results show at the global level that economic growth has the greatest impact on CO 2 emissions, and the proportion of the population between ages 15 and 64 has the least impact. The proportion of the population between 15 and 64 has a negative impact on the total CO 2 emissions of countries at the high income level, but the impact is positive at other income levels. This may illustrate the importance of the 'B' in the 'I = PABT'; that is to say that different behavior fashions can greatly influence environmental change. For low-income countries, the impact of GDP per capita on total CO 2 emissions is very great, and the impact of energy intensity in upper-middle income countries is very great. The impact of these factors on the total CO 2 emissions of countries at the high income level is relatively great. Therefore, these empirical results indicate that the impact of population, affluence and technology on CO 2 emissions varies at different levels of development. Thus, policy-makers should consider these matters fully when they construct their long-term strategies for CO 2 abatement

Exhaust constituent emission factors of printed circuit board pyrolysis processes and its exhaust control

Energy Technology Data Exchange (ETDEWEB)

Chiang, Hung-Lung, E-mail: hlchiang@mail.cmu.edu.tw [Department of Health Risk Management, China Medical University, Taichung, Taiwan (China); Lin, Kuo-Hsiung [Department of Environmental Engineering and Science, Fooyin University, Kaohsiung, Taiwan (China)

2014-01-15

Highlights: • Recycling of waste printed circuit boards is an important issue. • Pyrolysis is an emerging technology for PCB treatment. • Emission factors of VOCs are determined for PCB pyrolysis exhaust. • Iron-Al{sub 2}O{sub 3} catalyst was employed for the exhaust control. -- Abstract: The printed circuit board (PCB) is an important part of electrical and electronic equipment, and its disposal and the recovery of useful materials from waste PCBs (WPCBs) are key issues for waste electrical and electronic equipment. Waste PCB compositions and their pyrolysis characteristics were analyzed in this study. In addition, the volatile organic compound (VOC) exhaust was controlled by an iron-impregnated alumina oxide catalyst. Results indicated that carbon and oxygen were the dominant components (hundreds mg/g) of the raw materials, and other elements such as nitrogen, bromine, and copper were several decades mg/g. Exhaust constituents of CO, H{sub 2}, CH{sub 4}, CO{sub 2}, and NOx, were 60–115, 0.4–4.0, 1.1–10, 30–95, and 0–0.7 mg/g, corresponding to temperatures ranging from 200 to 500 °C. When the pyrolysis temperature was lower than 300 °C, aromatics and paraffins were the major species, contributing 90% of ozone precursor VOCs, and an increase in the pyrolysis temperature corresponded to a decrease in the fraction of aromatic emission factors. Methanol, ethylacetate, acetone, dichloromethane, tetrachloromethane and acrylonitrile were the main species of oxygenated and chlorinated VOCs. The emission factors of some brominated compounds, i.e., bromoform, bromophenol, and dibromophenol, were higher at temperatures over 400 °C. When VOC exhaust was flowed through the bed of Fe-impregnated Al{sub 2}O{sub 3}, the emission of ozone precursor VOCs could be reduced by 70–80%.

LBA-ECO TG-10 Fire Emission Factors in Mato Grosso, Para, and Amazonas, Brazil: 2004

Data.gov (United States)

National Aeronautics and Space Administration — ABSTRACT: This data set provides derived emission factors (EFs), reported in grams of compound emitted per kilogram of dry fuel (g/kg), for PM10 (particulate matter...

Study of greenhouse gases emission factor for nuclear power chain of China

International Nuclear Information System (INIS)

Ma Zhonghai; Pan Ziqiang; Xie Jianlun; Xiu Binglin

2001-01-01

The Greenhouse Gases Emission Factor (GGEF) for nuclear power chain of China is calculated based on Life Cycle Analysis method and the definition of full energy chain. There is no greenhouse gases released directly from nuclear power plant. The greenhouse gases emission from nuclear power plant is mainly from coal-fired electricity supply to nuclear power plant for its normal operation and the production of construction materials those are used in the nuclear power plant. The total GGEF of nuclear power chain in China is 13.71 g-co 2 /kWh. It is necessary to regulate un-rational power source mix and to use the energy sources in rational way for reducing the greenhouse gas effect. Nuclear power for electricity generation is one of effective ways to reduce greenhouse gases emission and retard the greenhouse effect

Development of real-world driving cycles and estimation of emission factors for in-use light-duty gasoline vehicles in urban areas.

Science.gov (United States)

Hwa, Mei-Yin; Yu, Tai-Yi

2014-07-01

This investigation adopts vehicle tracking manner to establish real-world driving patterns and estimates emission factors with dynamometers with 23 traffic-driving variables for 384 in-use light-duty passenger vehicles during non-rush hour. Adequate numbers of driving variables were decided with factor analysis and cluster analysis. The dynamometer tests were performed on FTP75 cycle and five local driving cycles derived from real-world speed profiles. Results presented that local driving cycles and FTP75 cycle were completely different in driving characteristic parameters of typical driving cycles and emission factors. The highest values of emission factor ratios of local driving cycle and FTP75 cycle for CO, NMHC, NO x , CH4, and CO2 were 1.38, 1.65, 1.58, 1.39, and 1.14, respectively.

Solid Particle Number Emission Factors of Euro VI Heavy-Duty Vehicles on the Road and in the Laboratory

Science.gov (United States)

Giechaskiel, Barouch

2018-01-01

Particulate matter (PM), and in particular ultrafine particles, have a negative impact on human health. The contribution of vehicle PM emissions to air pollution is typically quantified with emission inventories, which need vehicle emission factors as input. Heavy-duty vehicles, although they represent a small percentage of the vehicle population in nearly every major country, contribute the majority of the on-road PM emissions. However, the published data of modern heavy-duty vehicle emissions are scarce, and for the newest Euro VI technologies, almost non-existent. The main objective of this paper is to present Solid Particle Number (SPN) emission factors from Euro VI heavy-duty vehicles using diesel, Compressed Natural Gas (CNG), or Liquefied Natural Gas (LNG). Urban, rural and motorway (highway) emissions were determined on the road at various European cities using SPN Portable Emission Measurement Systems (PEMS). Additional tests on a heavy-duty chassis dynamometer showed that the solid sub-23 nm fraction, which is not covered at the moment in the European regulation, is high, especially for CNG engines. The significant contribution of regeneration events and the effect of ambient temperature and engine cold-start on particle emissions were also discussed. PMID:29425174

Solid Particle Number Emission Factors of Euro VI Heavy-Duty Vehicles on the Road and in the Laboratory

Directory of Open Access Journals (Sweden)

Barouch Giechaskiel

2018-02-01

Full Text Available Particulate matter (PM, and in particular ultrafine particles, have a negative impact on human health. The contribution of vehicle PM emissions to air pollution is typically quantified with emission inventories, which need vehicle emission factors as input. Heavy-duty vehicles, although they represent a small percentage of the vehicle population in nearly every major country, contribute the majority of the on-road PM emissions. However, the published data of modern heavy-duty vehicle emissions are scarce, and for the newest Euro VI technologies, almost non-existent. The main objective of this paper is to present Solid Particle Number (SPN emission factors from Euro VI heavy-duty vehicles using diesel, Compressed Natural Gas (CNG, or Liquefied Natural Gas (LNG. Urban, rural and motorway (highway emissions were determined on the road at various European cities using SPN Portable Emission Measurement Systems (PEMS. Additional tests on a heavy-duty chassis dynamometer showed that the solid sub-23 nm fraction, which is not covered at the moment in the European regulation, is high, especially for CNG engines. The significant contribution of regeneration events and the effect of ambient temperature and engine cold-start on particle emissions were also discussed.

Solid Particle Number Emission Factors of Euro VI Heavy-Duty Vehicles on the Road and in the Laboratory.

Science.gov (United States)

Giechaskiel, Barouch

2018-02-09

Particulate matter (PM), and in particular ultrafine particles, have a negative impact on human health. The contribution of vehicle PM emissions to air pollution is typically quantified with emission inventories, which need vehicle emission factors as input. Heavy-duty vehicles, although they represent a small percentage of the vehicle population in nearly every major country, contribute the majority of the on-road PM emissions. However, the published data of modern heavy-duty vehicle emissions are scarce, and for the newest Euro VI technologies, almost non-existent. The main objective of this paper is to present Solid Particle Number (SPN) emission factors from Euro VI heavy-duty vehicles using diesel, Compressed Natural Gas (CNG), or Liquefied Natural Gas (LNG). Urban, rural and motorway (highway) emissions were determined on the road at various European cities using SPN Portable Emission Measurement Systems (PEMS). Additional tests on a heavy-duty chassis dynamometer showed that the solid sub-23 nm fraction, which is not covered at the moment in the European regulation, is high, especially for CNG engines. The significant contribution of regeneration events and the effect of ambient temperature and engine cold-start on particle emissions were also discussed.

Size-resolved particle emission factors for individual ships

Science.gov (United States)

Jonsson, Åsa M.; Westerlund, Jonathan; Hallquist, Mattias

2011-07-01

In these experiments size-resolved emission factors for particle number (EFPN) and mass (EFPM) have been determined for 734 individual ship passages for real-world dilution. The method used is an extractive sampling method of the passing ship plumes where particle number/mass and CO2 were measured with high time resolution (1 Hz). The measurements were conducted on a small island located in the entrance to the port of Gothenburg (N57.6849, E11.838), the largest harbor in Scandinavia. This is an emission control area (ECA) and in close vicinity to populated areas. The average EFPN and EFPM were 2.55 ± 0.11 × 1016 (kg fuel)-1 and 2050 ± 110 mg (kg fuel)-1, respectively. The determined EF for ships with multiple passages showed a great reproducibility. Size-resolved EFPN were peaking at small particle sizes ˜35 nm. Smaller particle sizes and hence less mass were observed by a gas turbine equipped ship compared to diesel engine equipped ships. On average 36 to 46% of the emitted particles by number were non-volatile and 24% by mass (EFPN 1.16 ± 0.19 × 1016 [kg fuel]-1 and EFPM 488 ± 73 mg [kg fuel]-1, respectively). This study shows a great potential to gain large data-sets regarding ship emission determining parameters that can improve current dispersion modeling for health assessments on local and regional scales. The global contributions of total and non-volatile particle mass from shipping using this extensive data-set from an ECA were estimated to be at least 0.80 Tgy-1 and 0.19 Tgy-1.

Averaged emission factors for the Hungarian car fleet

Energy Technology Data Exchange (ETDEWEB)

Haszpra, L. [Inst. for Atmospheric Physics, Budapest (Hungary); Szilagyi, I. [Central Research Inst. for Chemistry, Budapest (Hungary)

1995-12-31

The vehicular emission of non-methane hydrocarbon (NMHC) is one of the largest anthropogenic sources of NMHC in Hungary and in most of the industrialized countries. Non-methane hydrocarbon plays key role in the formation of photo-chemical air pollution, usually characterized by the ozone concentration, which seriously endangers the environment and human health. The ozone forming potential of the different NMHCs differs from each other significantly, while the NMHC composition of the car exhaust is influenced by the fuel and engine type, technical condition of the vehicle, vehicle speed and several other factors. In Hungary the majority of the cars are still of Eastern European origin. They represent the technological standard of the 70`s, although there are changes recently. Due to the long-term economical decline in Hungary the average age of the cars was about 9 years in 1990 and reached 10 years by 1993. The condition of the majority of the cars is poor. In addition, almost one third (31.2 %) of the cars are equipped with two-stroke engines which emit less NO{sub x} but much more hydrocarbon. The number of cars equipped with catalytic converter was negligible in 1990 and is slowly increasing only recently. As a consequence of these facts the traffic emission in Hungary may differ from that measured in or estimated for the Western European countries and the differences should be taken into account in the air pollution models. For the estimation of the average emission of the Hungarian car fleet a one-day roadway tunnel experiment was performed in the downtown of Budapest in summer, 1991. (orig.)

LBA-ECO TG-10 Fire Emission Factors in Mato Grosso, Para, and Amazonas, Brazil: 2004

Data.gov (United States)

National Aeronautics and Space Administration — This data set provides derived emission factors (EFs), reported in grams of compound emitted per kilogram of dry fuel (g/kg), for PM10 (particulate matter up to 10...

Fate factors and emission flux estimates for emerging contaminants in surface waters

Directory of Open Access Journals (Sweden)

Hoa T. Trinh

2016-01-01

Full Text Available Pharmaceuticals, personal care products, hormones, and wastewater products are emerging environmental concerns for manifold reasons, including the potential of some compounds found in these products for endocrine disruption at a very low chronic exposure level. The environmental occurrences and sources of these contaminants in the water, soil, sediment and biota in European nations and the United States are well documented. This work reports a screening-level emission and fate assessment of thirty compounds, listed in the National Reconnaissance of the United States Geological Survey (USGS, 1999–2000 as the most frequently detected organic wastewater contaminants in U.S. streams and rivers. Estimations of the surface water fate factors were based on Level II and Level III multimedia fugacity models for a 1000 km2 model environment, the size of a typical county in the eastern United States. The compounds are categorized into three groups based upon the sensitivity of their predicted surface water fate factors to uncertainties in their physicochemical property values and the landscape parameters. The environmental fate factors, mass distributions, and loss pathways of all of the compounds are strongly affected by their assumed modes of entry into the environment. It is observed that for thirteen of the thirty organic wastewater contaminants most commonly detected in surface waters, conventional treatment strategies may be ineffective for their removal from wastewater effluents. The surface water fate factors predicted by the fugacity models were used in conjunction with the surface water concentrations measured in the USGS reconnaissance to obtain emission flux estimates for the compounds into U.S. streams and rivers. These include estimated fluxes of 6.8 × 10−5 to 0.30 kg/h km2 for the biomarker coprostanol; 1.7 × 10−5 to 6.5 × 10−5 kg/h km2 for the insect repellent N,N-diethyltoluamide; and 4.3 × 10−6 to 3.1 × 10−5 kg/h km2 for

A decomposition analysis of the driving factors of CO_2 (Carbon dioxide) emissions from the power sector in the European Union countries

International Nuclear Information System (INIS)

Karmellos, M.; Kopidou, D.; Diakoulaki, D.

2016-01-01

The scope of this paper is to investigate the driving factors of CO_2 emissions from electricity generation in all European Union countries (EU-28) during the period 2000–2012. Particular emphasis is placed on the assessment of any potential association between the examined driving factors and major climate and energy policies implemented during the examined period. In addition, the analysis distinguishes two subperiods, namely 2000–2007 and 2007–2012 in order to detect the impact of the economic crisis on each distinct driving factor and, consequently, on the total level of CO_2 emissions from the power sector. The model developed to analyse the changes in CO_2 emissions from the power sector across EU-28, is based on LMDI-I method and takes into account five driving factors: level of activity, electricity intensity, electricity trade, efficiency of electricity generation and fuel mix. The obtained results show that in times of economic growth the main factor counterbalancing the activity effect was in most countries the decreasing electricity intensity, while the contribution of all other factors becomes apparent later, despite the economic crisis and in view of the Kyoto targets. - Highlights: • LMDI is used to identify driving forces of CO_2 emissions from EU's power sector. • Declining electricity intensity was the main restrictive factor before 2007. • Fuel shifts contributed to emissions fall mostly after 2007, despite the crisis. • Trade effect is notable and indicates growing carbon leakage in the power sector.

Update of emission factors for nitrous oxide from agricultural soils on the basis of measurements in the Netherlands

NARCIS (Netherlands)

Kuikman, P.J.; Hoek, van der K.W.; Smit, A.; Zwart, K.B.

2006-01-01

Emissions of nitrous oxide (N2O) in the Netherlands are reported to the UNFCCC on the basis of a country specific methodology. In this study we have identified and analysed the values for emission factors in measurement from in the Netherlands in the period 1993 – 2003. The overall averaged emission

Dioxin emission factors for automobiles from tunnel air sampling in Northern Taiwan.

Science.gov (United States)

Chang, Moo Been; Chang, Shu Hao; Chen, Yuan Wu; Hsu, Hsuan Chien

2004-06-05

This study measured PCDD/F concentrations in tunnel air and vehicle exhaust. The ambient air samples were collected with air samplers (Tisch PS-1) complying with USEPA TO-9A. The results indicate that the tunnel air had a PCDD/F TEQ concentration about two times as high as that of outside air (47.3 and 57.1 fg-I-TEQ/m3 for tunnel air vs. 37.1 fg-I-TEQ/m3 and 23.3 fg-I-TEQ/m3 for outside air, respectively). This provides the direct evidence that PCDD/F compounds are emitted from the combustion processes in gasoline- and diesel-fueled engines. According to the tunnel study, the emission factors ranged from 5.83 to 59.2 pg I-TEQ/km for gasoline vehicles and 23.32 to 236.65 pg I-TEQ/km of diesel vehicles. This indicates that the dioxin emission factor in Taiwan is lower than that measured in USA, Norway and Germany. When the speed of the diesel vehicle was set at 40 km/h, the dioxin concentration emitted from diesel vehicle was 278 pg/m3 (6.27 pg-I-TEQ/m3) from tailpipe testing. However, when the diesel vehicle was idled, the dioxin concentration increased greatly to 4078 pg/m3 (41.9 pg-I-TEQ/m3). From the results of tunnel air sampling, the PCDD/Fs emission from automobiles in Taiwan was estimated as 3.69 g I-TEQ per year. Copryright 2003 Elsevier B.V.

Driving factors of carbon dioxide emissions and the impact from Kyoto Protocol

Energy Technology Data Exchange (ETDEWEB)

Grunewald, Nicole [Goettingen Univ. (Germany). Dept. of Economics; Martinez-Zarzoso, Inmaculada [Jaume I Univ. (Spain). International Economics Institute

2009-08-15

In the last two decades increasing attention has been paid to the relationship between environmental degradation and economic development. According to the Environmental Kuznets Curve (EKC) hypothesis this relationship may be described by an inverted-U curve. However, recent evidence rejects the EKC hypothesis for GHG emissions in a broad sense. In this paper we aim to investigate whether the EKC behavior for CO2 emissions could be proved on the behalf of institutional regulations. We analyze the driving factors of CO2 for developed and developing countries to test the theory of the EKC in the context of environmental regulations using a static and dynamic panel data model. We consider the Kyoto Protocol and the Clean Development Mechanism (CDM). The results from this study indicate that the Kyoto obligations have a reducing effect on CO2 emissions in developed and developing countries. (orig.)

Identification of factors most important for ammonia emission from fertilized soils for potato production using principal component analysis

Science.gov (United States)

Guodoong Liu; Yuncong Li; Kati W. Migliaccio; Ying Ouyang; Ashok K. Alva

2011-01-01

Ammonia (NH3) emissions from fertilized soils are a costly problem that is undermining agricultural and ecological sustainability worldwide. Ammonia emissions from crop production have been reliably documented in recent years. However, insufficient efforts have been made to determine the factors most influential in facilitating NH3 emissions. The goal of this study was...

Towards factor analysis exploration applied to positron emission tomography functional imaging for breast cancer characterization

International Nuclear Information System (INIS)

Rekik, W.; Ketata, I.; Sellami, L.; Ben slima, M.; Ben Hamida, A.; Chtourou, K.; Ruan, S.

2011-01-01

This paper aims to explore the factor analysis when applied to a dynamic sequence of medical images obtained using nuclear imaging modality, Positron Emission Tomography (PET). This latter modality allows obtaining information on physiological phenomena, through the examination of radiotracer evolution during time. Factor analysis of dynamic medical images sequence (FADMIS) estimates the underlying fundamental spatial distributions by factor images and the associated so-called fundamental functions (describing the signal variations) by factors. This method is based on an orthogonal analysis followed by an oblique analysis. The results of the FADMIS are physiological curves showing the evolution during time of radiotracer within homogeneous tissues distributions. This functional analysis of dynamic nuclear medical images is considered to be very efficient for cancer diagnostics. In fact, it could be applied for cancer characterization, vascularization as well as possible evaluation of response to therapy.

Estimation of the emission factors of PAHs by traffic with the model of atmospheric dispersion and deposition from heavy traffic road.

Science.gov (United States)

Ozaki, N; Tokumitsu, H; Kojima, K; Kindaichi, T

2007-01-01

In order to consider the total atmospheric loadings of the PAHs (polycyclic aromatic hydrocarbons) from traffic activities, the emission factors of PAHs were estimated and from the obtained emission factors and vehicle transportation statistics, total atmospheric loadings were integrated and the loadings into the water body were estimated on a regional scale. The atmospheric concentration of PAHs was measured at the roadside of a road with heavy traffic in the Hiroshima area in Japan. The samplings were conducted in summer and winter. Atmospheric particulate matters (fine particle, 0.6-7 microm; coarse particle, over 7 microm) and their PAH concentration were measured. Also, four major emission sources (gasoline and diesel vehicle emissions, tire and asphalt debris) were assumed for vehicle transportation activities, the chemical mass balance method was applied and the source partitioning at the roadside was estimated. Furthermore, the dispersion of atmospheric particles from the vehicles was modelled and the emission factors of the sources were determined by the comparison to the chemical mass balance results. Based on emission factors derived from the modelling, an atmospheric dispersion model of nationwide scale (National Institute of Advanced Industrial Science and Technology - Atmospheric Dispersion Model for Exposure and Risk assessment) was applied, and the atmospheric concentration and loading to the ground were calculated for the Hiroshima Bay watershed area.

Role of management strategies and environmental factors in determining the emissions of biogenic volatile organic compounds from urban greenspaces.

Science.gov (United States)

Ren, Yuan; Ge, Ying; Gu, Baojing; Min, Yong; Tani, Akira; Chang, Jie

2014-06-03

Biogenic volatile organic compound (BVOC) emissions from urban greenspace have recently become a global concern. To identify key factors affecting the dynamics of urban BVOC emissions, we built an estimation model and utilized the city of Hangzhou in southeastern China as an example. A series of single-factor scenarios were first developed, and then nine multifactor scenarios using a combination of different single-factor scenarios were built to quantify the effects of environmental changes and urban management strategies on urban BVOC emissions. Results of our model simulations showed that (1) annual total BVOC emissions from the metropolitan area of Hangzhou were 4.7×10(8) g of C in 2010 and were predicted to be 1.2-3.2 Gg of C (1 Gg=10(9) g) in our various scenarios in 2050, (2) urban management played a more important role in determining future urban BVOC emissions than environmental changes, and (3) a high ecosystem service value (e.g., lowest BVOC/leaf mass ratio) could be achieved through positive coping in confronting environmental changes and adopting proactive urban management strategies on a local scale, that is, to moderately increase tree density while restricting excessive greenspace expansion and optimizing the species composition of existing and newly planted trees.

A Global Outlook to the Carbon Dioxide Emissions in the World and Emission Factors of the Thermal Power Plants in Turkey

International Nuclear Information System (INIS)

Atimtay, Aysel T.

2003-01-01

World primary energy demand increases with increases in population and economic development. Within the last 25 yr, the total energy consumption has almost doubled. For the purpose of meeting this demand, fossil energy sources are used and various pollutants are generated. CO 2 is also one of these gases, which cannot be removed like other pollutants, and it causes greenhouse effect and climate change. Reducing the CO 2 emission is very important because of the environmental concerns and regulations, especially the Kyoto Protocol. This paper reviews the estimated world carbon emissions, Turkey's situation in electrical energy production, emission amounts estimated until the year 2020 and emission factors for dust, SO 2 , NO x and CO 2 . The estimated results show that CO 2 emissions from thermal power plants in Turkey will make about 0.66 % of the global CO 2 emissions in 2020

Sensitivity Analysis of b-factor in Microwave Emission Model for Soil Moisture Retrieval: A Case Study for SMAP Mission

Directory of Open Access Journals (Sweden)

Dugwon Seo

2010-05-01

Full Text Available Sensitivity analysis is critically needed to better understand the microwave emission model for soil moisture retrieval using passive microwave remote sensing data. The vegetation b-factor along with vegetation water content and surface characteristics has significant impact in model prediction. This study evaluates the sensitivity of the b-factor, which is function of vegetation type. The analysis is carried out using Passive and Active L and S-band airborne sensor (PALS and measured field soil moisture from Southern Great Plains experiment (SGP99. The results show that the relative sensitivity of the b-factor is 86% in wet soil condition and 88% in high vegetated condition compared to the sensitivity of the soil moisture. Apparently, the b-factor is found to be more sensitive than the vegetation water content, surface roughness and surface temperature; therefore, the effect of the b-factor is fairly large to the microwave emission in certain conditions. Understanding the dependence of the b-factor on the soil and vegetation is important in studying the soil moisture retrieval algorithm, which can lead to potential improvements in model development for the Soil Moisture Active-Passive (SMAP mission.

Characterization of air pollutant concentrations, fleet emission factors, and dispersion near a North Carolina interstate freeway across two seasons

Science.gov (United States)

Saha, Provat K.; Khlystov, Andrey; Snyder, Michelle G.; Grieshop, Andrew P.

2018-03-01

We present field measurement data and modeling of multiple traffic-related air pollutants during two seasons at a site adjoining Interstate 40, near Durham, North Carolina. We analyze spatial-temporal and seasonal trends and fleet-average pollutant emission factors and use our data to evaluate a line source dispersion model. Month-long measurement campaigns were performed in summer 2015 and winter 2016. Data were collected at a fixed near-road site located within 10 m from the highway edge, an upwind background site and, under favorable meteorological conditions, along downwind perpendicular transects. Measurements included the size distribution, chemical composition, and volatility of submicron particles, black carbon (BC), nitrogen oxides (NOx), meteorological conditions and traffic activity data. Results show strong seasonal and diurnal differences in spatial distribution of traffic sourced pollutants. A strong signature of vehicle emissions was observed within 100-150 m from the highway edge with significantly higher concentrations during morning. Substantially higher concentrations and less-sharp near-road gradients were observed in winter for many species. Season-specific fleet-average fuel-based emission factors for NO, NOx, BC, and particle number (PN) were derived based on up- and down-wind roadside measurements. The campaign-average NOx and PN emission factors were 20% and 300% higher in winter than summer, respectively. These results suggest that the combined effect of higher emissions and their slower downwind dispersion in winter dictate the observed higher downwind concentrations and wider highway influence zone in winter for several species. Finally, measurements of traffic data, emission factors, and pollutant concentrations were integrated to evaluate a line source dispersion model (R-LINE). The dispersion model captured the general trends in the spatial and temporal patterns in near-road concentrations. However, there was a tendency for the model

Combustion efficiency and emission factors for wildfire-season fires in mixed conifer forests of the northern Rocky Mountains, US

Science.gov (United States)

S. P. Urbanski

2013-01-01

In the US, wildfires and prescribed burning present significant challenges to air regulatory agencies attempting to achieve and maintain compliance with air quality regulations. Fire emission factors (EF) are essential input for the emission models used to develop wildland fire emission inventories. Most previous studies quantifying wildland fire EF of temperate...

Development and review of Euro 5 passenger car emission factors based on experimental results over various driving cycles.

Science.gov (United States)

Fontaras, Georgios; Franco, Vicente; Dilara, Panagiota; Martini, Giorgio; Manfredi, Urbano

2014-01-15

The emissions of CO2 and regulated pollutants (NOx, HC, CO, PM) of thirteen Euro 5 compliant passenger cars (seven gasoline, six Diesel) were measured on a chassis dynamometer. The vehicles were driven repeatedly over the European type-approval driving cycle (NEDC) and the more dynamic WMTC and CADC driving cycles. Distance-specific emission factors were derived for each pollutant and sub-cycle, and these were subsequently compared to the corresponding emission factors provided by the reference European models used for vehicle emission inventory compilation (COPERT and HBEFA) and put in context with the applicable European emission limits. The measured emissions stayed below the legal emission limits when the type-approval cycle (NEDC) was used. Over the more dynamic cycles (considered more representative of real-world driving) the emissions were consistently higher but in most cases remained below the type-approval limit. The high NOx emissions of Diesel vehicles under real-world driving conditions remain the main cause for environmental concern regarding the emission profile of Euro 5 passenger cars. Measured emissions of NOx exceeded the type-approval limits (up to 5 times in extreme cases) and presented significantly increased average values (0.35 g/km for urban driving and 0.56 g/km for motorway driving). The comparison with the reference models showed good correlation in all cases, a positive finding considering the importance of these tools in emission monitoring and policy-making processes. © 2013. Published by Elsevier B.V. All rights reserved.

Variability in Light-Duty Gasoline Vehicle Emission Factors from Trip-Based Real-World Measurements.

Science.gov (United States)

Liu, Bin; Frey, H Christopher

2015-10-20

Using data obtained with portable emissions measurements systems (PEMS) on multiple routes for 100 gasoline vehicles, including passenger cars (PCs), passenger trucks (PTs), and hybrid electric vehicles (HEVs), variability in tailpipe emission rates was evaluated. Tier 2 emission standards are shown to be effective in lowering NOx, CO, and HC emission rates. Although PTs are larger, heavier vehicles that consume more fuel and produce more CO2 emissions, they do not necessarily produce more emissions of regulated pollutants compared to PCs. HEVs have very low emission rates compared to tier 2 vehicles under real-world driving. Emission factors vary with cycle average speed and road type, reflecting the combined impact of traffic control and traffic congestion. Compared to the slowest average speed and most congested cycles, optimal emission rates could be 50% lower for CO2, as much as 70% lower for NOx, 40% lower for CO, and 50% lower for HC. There is very high correlation among vehicles when comparing driving cycles. This has implications for how many cycles are needed to conduct comparisons between vehicles, such as when comparing fuels or technologies. Concordance between empirical and predicted emission rates using the U.S. Environmental Protection Agency's MOVES model was also assessed.

Isoprene Emission Factors for Subtropical Street Trees for Regional Air Quality Modeling.

Science.gov (United States)

Dunn-Johnston, Kristina A; Kreuzwieser, Jürgen; Hirabayashi, Satoshi; Plant, Lyndal; Rennenberg, Heinz; Schmidt, Susanne

2016-01-01

Evaluating the environmental benefits and consequences of urban trees supports their sustainable management in cities. Models such as i-Tree Eco enable decision-making by quantifying effects associated with particular tree species. Of specific concern are emissions of biogenic volatile organic compounds, particularly isoprene, that contribute to the formation of photochemical smog and ground level ozone. Few studies have quantified these potential disservices of urban trees, and current models predominantly use emissions data from trees that differ from those in our target region of subtropical Australia. The present study aimed (i) to quantify isoprene emission rates of three tree species that together represent 16% of the inventoried street trees in the target region; (ii) to evaluate outputs of the i-Tree Eco model using species-specific versus currently used, generic isoprene emission rates; and (iii) to evaluate the findings in the context of regional air quality. Isoprene emission rates of (Myrtaceae) and (Proteaceae) were 2.61 and 2.06 µg g dry leaf weight h, respectively, whereas (Sapindaceae) was a nonisoprene emitter. We substituted the generic isoprene emission rates with these three empirical values in i-Tree Eco, resulting in a 182 kg yr (97%) reduction in isoprene emissions, totaling 6284 kg yr when extrapolated to the target region. From these results we conclude that care has to be taken when using generic isoprene emission factors for urban tree models. We recommend that emissions be quantified for commonly planted trees, allowing decision-makers to select tree species with the greatest overall benefit for the urban environment. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Impact of some field factors on inhalation exposure levels to bitumen emissions during road paving operations.

Science.gov (United States)

Deygout, François; Auburtin, Guy

2015-03-01

Variability in occupational exposure levels to bitumen emissions has been observed during road paving operations. This is due to recurrent field factors impacting the level of exposure experienced by workers during paving. The present study was undertaken in order to quantify the impact of such factors. Pre-identified variables currently encountered in the field were monitored and recorded during paving surveys, and were conducted randomly covering current applications performed by road crews. Multivariate variance analysis and regressions were then used on computerized field data. The statistical investigations were limited due to the relatively small size of the study (36 data). Nevertheless, the particular use of the step-wise regression tool enabled the quantification of the impact of several predictors despite the existing collinearity between variables. The two bitumen organic fractions (particulates and volatiles) are associated with different field factors. The process conditions (machinery used and delivery temperature) have a significant impact on the production of airborne particulates and explain up to 44% of variability. This confirms the outcomes described by previous studies. The influence of the production factors is limited though, and should be complemented by studying factors involving the worker such as work style and the mix of tasks. The residual volatile compounds, being part of the bituminous binder and released during paving operations, control the volatile emissions; 73% of the encountered field variability is explained by the composition of the bitumen batch. © The Author 2014. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

Advancing national greenhouse gas inventories for agriculture in developing countries: improving activity data, emission factors and software technology

International Nuclear Information System (INIS)

Ogle, Stephen M; Hartman, Melannie; Spencer, Shannon; Buendia, Leandro; Butterbach-Bahl, Klaus; Breidt, F Jay; Yagi, Kazuyuki; Nayamuth, Rasack; Wirth, Tom; Smith, Pete

2013-01-01

Developing countries face many challenges when constructing national inventories of greenhouse gas (GHG) emissions, such as lack of activity data, insufficient measurements for deriving country-specific emission factors, and a limited basis for assessing GHG mitigation options. Emissions from agricultural production are often significant sources in developing countries, particularly soil nitrous oxide, and livestock enteric and manure methane, in addition to wetland rice methane. Consequently, estimating GHG emissions from agriculture is an important part of constructing developing country inventories. While the challenges may seem insurmountable, there are ways forward such as: (a) efficiently using resources to compile activity data by combining censuses and surveys; (b) using a tiered approach to measure emissions at appropriately selected sites, coupled with modeling to derive country-specific emission factors; and (c) using advanced software systems to guide compilers through the inventory process. With a concerted effort by compilers and assistance through capacity-building efforts, developing country compilers could produce transparent, accurate, complete, consistent and comparable inventories, as recommended by the IPCC (Intergovernmental Panel on Climate Change). In turn, the resulting inventories would provide the foundation for robust GHG mitigation analyses and allow for the development of nationally appropriate mitigation actions and low emission development strategies. (letter)

[Perinatal factors affecting the detection of otoacoustic emissions in vaginally delivered, healthy newborns, during the first 48 hours of life].

Science.gov (United States)

Sequi-Canet, José M; Sala-Langa, María J; Collar Del Castillo, José I

2014-01-01

Most hospitals perform neonatal hearing screening because it is a very useful procedure. Otoacoustic emissions are an ideal technique for this screening. We analyse the possible influence on screening results of some perinatal factors. We collected retrospective data from 8,239 healthy newborns delivered vaginally at the maternity ward of our hospital. We compared multiple perinatal factors vs the results of otoacoustic emissions performed within the first 48 h of life, before discharge. A total of 6.4% of newborns had an abnormal response and failed the screening. Univariate and multivariate analysis showed a significant (P<.0001) positive relationship between breastfeeding and normal otoacoustic emissions (OR: 0.65). Another, less significant factor was female gender. The remaining variables, including origin, education or employment status of the mother, maternal smoking, dystocic delivery, presentation, need for resuscitation, preterm labour (34-36 weeks), weight, length and frequent maternal pathology, such as streptococcus detection, hypothyroidism, hypertension or diabetes, were not significant. Breastfeeding was the most important factor related to a normal response in otoacoustic emissions. It may improve final results and reduce the number of neonates who need to be rescheduled for a repeated test, as well as the associated anxiety and the possibility of losing patients during follow-up. These are major problems in neonatal hearing screening. Copyright © 2013 Elsevier España, S.L. All rights reserved.

Characterisation factors for life cycle impact assessment of sound emissions.

Science.gov (United States)

Cucurachi, S; Heijungs, R

2014-01-15

Noise is a serious stressor affecting the health of millions of citizens. It has been suggested that disturbance by noise is responsible for a substantial part of the damage to human health. However, no recommended approach to address noise impacts was proposed by the handbook for life cycle assessment (LCA) of the European Commission, nor are characterisation factors (CFs) and appropriate inventory data available in commonly used databases. This contribution provides CFs to allow for the quantification of noise impacts on human health in the LCA framework. Noise propagation standards and international reports on acoustics and noise impacts were used to define the model parameters. Spatial data was used to calculate spatially-defined CFs in the form of 10-by-10-km maps. The results of this analysis were combined with data from the literature to select input data for representative archetypal situations of emission (e.g. urban day with a frequency of 63 Hz, rural night at 8000 Hz, etc.). A total of 32 spatial and 216 archetypal CFs were produced to evaluate noise impacts at a European level (i.e. EU27). The possibility of a user-defined characterisation factor was added to support the possibility of portraying the situation of full availability of information, as well as a highly-localised impact analysis. A Monte Carlo-based quantitative global sensitivity analysis method was applied to evaluate the importance of the input factors in determining the variance of the output. The factors produced are ready to be implemented in the available LCA databases and software. The spatial approach and archetypal approach may be combined and selected according to the amount of information available and the life cycle under study. The framework proposed and used for calculations is flexible enough to be expanded to account for impacts on target subjects other than humans and to continents other than Europe. © 2013 Elsevier B.V. All rights reserved.

Emission factors from road traffic from a tunnel study (Gubrist tunnel, Switzerland). Part 1 Concept and first results

Energy Technology Data Exchange (ETDEWEB)

Staehelin, Johannes; Brunner, Dominik; Baumle, Martin [Atmospheric Science, ETH-Hoenggerberg, Zuerich (Switzerland); Schlapfer, Kurt [Carbotech AG, Basel (Switzerland); Burgin, Toni; Meier, Markus [Amt fuer Technische Anlagen und Lufthygiene Kanton Zuerich ATAL, Zuerich (Switzerland); Steinemann, Urs [Ingenieurbuero Steinemann, Wollerau (Switzerland); Schneider, Stefan; Zahner, Christoph; Keiser, Stephan [Planungsbuero Jud AG, Zuerich (Switzerland); Stahel, Werner; Keller, Christian [Sem. for Statistics, ETH-Z, Zuerich (Switzerland)

1995-06-22

In the industrialized world a large part of the emission of the primary air pollutants (NO{sub x}, volatile organic compounds (VOC) and CO) originates from road traffic. Here we present the concept and first results of a tunnel study which took place from September 20th to September 26th, 1993, at the Gubrist tunnel (close to Zuerich, Switzerland) in which the emission factors of a large number of individual VOCs, total hydrocarbons (t-HC), CO, NO{sub x} and SO{sub 2} are determined. The first tentative results of the emission factors of NO{sub x}, CO, t-HC and 26 individual hydrocarbons (alkanes and aromatics in the volatility range from n-heptane to n-decane) for the average of all vehicles and the light duty vehicles at an average speed of 90 km/h are given

The Scale, Structure and Influencing Factors of Total Carbon Emissions from Households in 30 Provinces of China—Based on the Extended STIRPAT Model

Directory of Open Access Journals (Sweden)

Yong Wang

2018-05-01

Full Text Available Household carbon emissions are important components of total carbon emissions. The consumer side of energy-saving emissions reduction is an essential factor in reducing carbon emissions. In this paper, the carbon emissions coefficient method and Consumer Lifestyle Approach (CLA were used to calculate the total carbon emissions of households in 30 provinces of China from 2006 to 2015, and based on the extended Stochastic Impacts by Regression on Population, Affluence, and Technology (STIRPAT model, the factors influencing the total carbon emissions of households were analyzed. The results indicated that, first, over the past ten years, the energy and products carbon emissions from China’s households have demonstrated a rapid growth trend and that regional distributions present obvious differences. Second, China’s energy carbon emissions due to household consumption primarily derived from the residents’ consumption of electricity and coal; China’s products household carbon emissions primarily derived from residents’ consumption of the high carbon emission categories: residences, food, transportation and communications. Third, in terms of influencing factors, the number of households in China plays a significant role in the total carbon emissions of China’s households. The ratio of children 0–14 years old and gender ratio (female = 100 are two factors that reflect the demographic structure, have significant effects on the total carbon emissions of China’s households, and are all positive. Gross Domestic Product (GDP per capita plays a role in boosting the total carbon emissions of China’s households. The effect of the carbon emission intensity on total household carbon emissions is positive. The industrial structure (the proportion of secondary industries’ added value to the regional GDP has curbed the growth of total carbon emissions from China’s household consumption. The results of this study provide data to support the

[Emission factors and PM chemical composition study of biomass burning in the Yangtze River Delta region].

Science.gov (United States)

Tang, Xi-Bin; Huang, Cheng; Lou, Sheng-Rong; Qiao, Li-Ping; Wang, Hong-Li; Zhou, Min; Chen, Ming-hua; Chen, Chang-Hong; Wang, Qian; Li, Gui-Ling; Li, Li; Huang, Hai-Ying; Zhang, Gang-Feng

2014-05-01

The emission characteristics of five typical crops, including wheat straw, rice straw, oil rape straw, soybean straw and fuel wood, were investigated to explore the gas and particulates emission of typical biomass burning in Yangzi-River-Delta area. The straws were tested both by burning in stove and by burning in the farm with a self-developed measurement system as open burning sources. Both gas and fine particle pollutants were measured in this study as well as the chemical composition of fine particles. The results showed that the average emission factors of CO, NO, and PM2,5 in open farm burning were 28.7 g.kg -1, 1.2 g.kg-1 and 2.65 g kg-1 , respectively. Due to insufficient burning in the low oxygen level environment, the emission factors of stove burning were higher than those of open farm burning, which were 81.9 g kg-1, 2. 1 g.kg -1 and 8.5 gkg -1 , respectively. Oil rape straw had the highest emission factors in all tested straws samples. Carbonaceous matter, including organic carbon(OC) and element carbon(EC) , was the foremost component of PM2, 5from biomass burning. The average mass fractions of OC and EC were (38.92 +/- 13.93)% and (5.66 +/-1.54)% by open farm burning and (26.37 +/- 10. 14)% and (18.97 +/- 10.76)% by stove burning. Water soluble ions such as Cl-and K+ had a large contribution. The average mass fractions of CI- and K+ were (13.27 +/-6. 82)% and (12.41 +/- 3.02)% by open farm burning, and were (16.25 +/- 9.34)% and (13.62 +/- 7.91)% by stove burning. The K +/OC values of particles from wheat straw, rice straw, oil rape straw and soybean straw by open farm burning were 0. 30, 0. 52, 0. 49 and 0. 15, respectively, which can be used to evaluate the influence on the regional air quality in YRD area from biomass burning and provide direct evidence for source apportionment.

The leaf-level emission factor of volatile isoprenoids: caveats, model algorithms, response shapes and scaling

Directory of Open Access Journals (Sweden)

Ü. Niinemets

2010-06-01

Full Text Available In models of plant volatile isoprenoid emissions, the instantaneous compound emission rate typically scales with the plant's emission potential under specified environmental conditions, also called as the emission factor, E_S. In the most widely employed plant isoprenoid emission models, the algorithms developed by Guenther and colleagues (1991, 1993, instantaneous variation of the steady-state emission rate is described as the product of E_S and light and temperature response functions. When these models are employed in the atmospheric chemistry modeling community, species-specific E_S values and parameter values defining the instantaneous response curves are often taken as initially defined. In the current review, we argue that E_S as a characteristic used in the models importantly depends on our understanding of which environmental factors affect isoprenoid emissions, and consequently need standardization during experimental E_S determinations. In particular, there is now increasing consensus that in addition to variations in light and temperature, alterations in atmospheric and/or within-leaf CO₂ concentrations may need to be included in the emission models. Furthermore, we demonstrate that for less volatile isoprenoids, mono- and sesquiterpenes, the emissions are often jointly controlled by the compound synthesis and volatility. Because of these combined biochemical and physico-chemical drivers, specification of E_S as a constant value is incapable of describing instantaneous emissions within the sole assumptions of fluctuating light and temperature as used in the standard algorithms. The definition of E_S also varies depending on the degree of aggregation of E_S values in different parameterization schemes (leaf- vs. canopy- or region-scale, species vs. plant functional type levels and various

40 CFR 94.218 - Deterioration factor determination.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Deterioration factor determination. 94... Deterioration factor determination. Manufacturers shall determine exhaust emission deterioration factors using good engineering judgement according to the provisions of this section. Every deterioration factor must...

Field Derived Emission Factors For Formaldehyde and other Volatile Organic Compounds in FEMA Temporary Housing Units

Energy Technology Data Exchange (ETDEWEB)

Parthasarathy, Srinandini; Maddalena, Randy L.; Russell, Marion L.; Apte, Michael G.

2010-10-01

Sixteen previously occupied temporary housing units (THUs) were studied to assess emissions of volatile organic compounds. The whole trailer emission factors wereevaluated for 36 VOCs including formaldehyde. Indoor sampling was carried out in the THUs located in Purvis staging yard in Mississippi, USA. Indoor temperature andrelative humidity (RH) were also measured in all the trailers during sampling. Indoor temperatures were varied (increased or decreased) in a selection of THUs using theheating, ventilation and air conditioning (HVAC) systems. Indoor temperatures during sampling ranged from 14o C to 33o C, and relative humidity (RH) varied between 35percentand 74percent. Ventilation rates were increased in some trailers using bathroom fans and vents during some of the sampling events. Ventilation rates measured during some aselection of sampling events varied from 0.14 to 4.3 h-1. Steady state indoor formaldehyde concentrations ranged from 10 mu g-m-3 to 1000 mu g-m-3. The formaldehyde concentrations in the trailers were of toxicological significance. The effects of temperature, humidity and ventilation rates were also studied. A linearregression model was built using log of percentage relative humidity, inverse of temperature (in K-1), and inverse log ACH as continuous independent variables, trailermanufacturer as a categorical independent variable, and log of the chemical emission factors as the dependent variable. The coefficients of inverse temperature, log relativehumidity, log inverse ACH with log emission factor were found to be statistically significant for all the samples at the 95percent confidence level. The regression model wasfound to explain about 84percent of the variation in the dependent variable. Most VOC concentrations measured indoors in the Purvis THUs were mostly found to be belowvalues reported in earlier studies by Maddalena et al.,1,2 Hodgson et al.,3 and Hippelein4. Emissions of TMPB-DIB (a plasticizer found in vinyl products) were found

Identification of the driving factors' influences on regional energy-related carbon emissions in China based on geographical detector method.

Science.gov (United States)

Zhang, Xinlin; Zhao, Yuan

2018-04-01

To investigate the influences of different factors on spatial heterogeneity of regional carbon emissions, we firstly studied the spatial-temporal dynamics of regional energy-related carbon emissions using global Moran's I and Getis-Ord Gi and applied geographical detector model to explain the spatial heterogeneity of regional carbon emissions. Some conclusions were drawn. Regional carbon emissions showed significant global and local spatial autocorrelation. The carbon emissions were greater in eastern and northern regions than in western and southern regions. Fixed assets investment and economic output had been the main contributing factors over the study period, and economic output had been decreasing its influence. Industrial structure's influence showed a decrease trend and became smaller in 2015. The results of the interaction detections in 2015 can be divided into two types: enhance and nonlinear, and enhance and bivariate. The interactive influences between technological level and fixed assets investment, economic output and technological level, population size and technological level, and economic output and economic development were greater than others. Some policy recommendations were proposed.

Development of net energy ratio and emission factor for quad-generation pathways

DEFF Research Database (Denmark)

Rudra, Souman; Rosendahl, Lasse; Kumar, Amit

2014-01-01

of this study was to evaluate the energy performance, reduce GHG and acid rain precursor emission, and use of biomass for different outputs based on demand. Finally, a sensitivity analysis and a comparative study ar conducted for expected technological improvements and factors that could increase the energy......, methanol and methane. Circulating fluidized bed gasifier and the gas technology institute (GTI) gasifier technologies are used for this quad-generation process. Two different biomass feedstocks are considered in this study. The net energy ratio for six different pathways having the range of between 1...

Particulate emission factor: A case study of a palm oil mill boiler

International Nuclear Information System (INIS)

Chong, W.C.; Rashid, M.; Ramli, M.; Zainura, Z.N.; NorRuwaida, J.

2010-01-01

A study to investigate the particulate emission from a boiler of a palm oil mill plant equipped with a multi-cyclones particulate arrest or was performed and reported in this paper. The particulate emission concentration was measured at the outlet of a 8 mt/ hr capacity water-tube typed boiler of a palm oil mill plant processing 27mt/ hr of fresh fruit bunch (FFB). The particulate sample was collected iso-kinetically using the USEPA method 5 sampling train through a sampling port made at the duct of the exiting flue gas between the boiler and a multi-cyclones unit. Results showed that the particulate emission rates exiting the boiler varied from 0.09 to 0.60 g/s with an average of 0.29 + 0.18 g/ s. While the average particulate emission concentration exiting the boiler was 12.1 + 7.36 g/ Nm 3 (corrected to 7 % oxygen concentration), ranging from 3.62 to 25.3 g/ Nm 3 (at 7 % O 2 ) of the flue gas during the measurement. Based on the 27 mt/ hr FFB processed and the capacity of the boiler of 8mt steam/ hr, the calculated particulate emission factor was 39 g particulate/ mt FFB processed or 131 g particulate/ mt boiler capacity, respectively. In addition, based on the finding and in order to comply with the emission limits of 0.4 g/ Nm 3 , the collection efficiency of any given particulate emission pollution control system to consider for the mill will be from 87 to 98 %, which is not easily achievable with the existing multi-cyclones unit. A considerable amount of efforts are still needed pertaining to the particulate emission control problem in the industry. (author)

Statistical analysis of nitrous oxide emission factors from pastoral agriculture field trials conducted in New Zealand

International Nuclear Information System (INIS)

Kelliher, F.M.; Cox, N.; Weerden, T.J. van der; Klein, C.A.M. de; Luo, J.; Cameron, K.C.; Di, H.J.; Giltrap, D.; Rys, G.

2014-01-01

Between 11 May 2000 and 31 January 2013, 185 field trials were conducted across New Zealand to measure the direct nitrous oxide (N 2 O) emission factors (EF) from nitrogen (N) sources applied to pastoral soils. The log(EF) data were analysed statistically using a restricted maximum likelihood (REML) method. To estimate mean EF values for each N source, best linear unbiased predictors (BLUPs) were calculated. For lowland soils, mean EFs for dairy cattle urine and dung, sheep urine and dung and urea fertiliser were 1.16 ± 0.19% and 0.23 ± 0.05%, 0.55 ± 0.19% and 0.08 ± 0.02% and 0.48 ± 0.13%, respectively, each significantly different from one another (p 12°, mean EFs were significantly lower. Thus, urine and dung EFs should be disaggregated for sheep and cattle as well as accounting for terrain. -- Highlights: • Nitrous oxide emission factors (EFs) for pastoral soils measured in 185 field trials. • For lowland, the mean (±standard error) urea nitrogen fertiliser EF was 0.5 ± 0.1%. • For lowland, mean dairy cattle urine and dung EFs were 1.2 and 0.2%, respectively. • For lowland, mean sheep urine and dung EFs were 0.6 and 0.1%, respectively. • For pastoral soils in terrain with slopes >12°, mean EFs were significantly lower. -- From 185 field trials, mean nitrous oxide emission factors for pastoral soils were 0.1% for sheep dung up to 1.2% for dairy cattle urine, while that for urea fertiliser was 0.5%

The astigmatism factor for semiconductor injection lasers

International Nuclear Information System (INIS)

Zhao Yiguang; Guo Changzhi

1988-03-01

The relations between the astigmatism factor and the waveguide structure, working conditions etc. were accurately calculated, using a method for deriving a self-consistent solution of the optical field equation and the carrier diffusion equation. Various theoretical models regarding the spontaneous emission factor were analyzed and compared. The results show that there is a difference between astigmatism factors of semiconductor lasers with different waveguide structures. W. Streifer's results, for a model having an invariable distribution of the complex refractive index, are larger by a factor of 6 to 80 than the accurate calculated value. K. Petermann's theory regarding the spontaneous emission factor is more appropriate than other theories. (author). 19 refs, 6 figs

On the indiscriminate use of imported emission factors in environmental impact assessment: A case study in Chile

International Nuclear Information System (INIS)

Bernal, María Fernanda; Oyarzún, Jorge; Oyarzún, Ricardo

2017-01-01

Environmental Impact Assessment (EIA) aims to determine if the environmental effect of an activity or project complies with standards and regulations. A primary component of the environment to evaluate is air and the effect that various activities can have on its quality. To this end, emission factors (EFs), which are empirical coefficients or mathematical relationships, are normally used. The present research critically analyzes the implications and consequences of using imported EFs in environmental impact studies (EISs), taking as case of study the situation in Chile. Among the main results, the widespread use of EFs in EISs in the country and the lack of assessments of their actual applicability stand out. In addition, the official guidelines related to emissions estimation that are used for EIA in the country mostly include EFs derived elsewhere, without considering the recommendations or restrictions that the original sources indicate for their use. Finally, the broad use of default values defined for the Metropolitan Region in Central Chile, is highly questionable for a country that extends north-south along more than 35° of latitude, with wide variability in climate, traffic conditions, population, soil types, etc. Finally, it is very likely that situations similar to those observed in the present work occurs in other countries with young environmental impact assessment systems, and therefore, that the results herein presented should be of general interest and relevance. - Highlights: • Emission factors are widely used in environmental impact assessment in Chile. • There is a lack of a proper understanding of the limitations of EFs for EIA. • Imported emission factors use requires caution and full understanding. • Misuse of foreign EFs may have serious environmental and economic consequences.

On the indiscriminate use of imported emission factors in environmental impact assessment: A case study in Chile

Energy Technology Data Exchange (ETDEWEB)

Bernal, María Fernanda [Civil and Environmental Engineering, Universidad de La Serena (Chile); Oyarzún, Jorge [Department of Mining Engineering, Universidad de La Serena (Chile); Oyarzún, Ricardo, E-mail: royarzun@userena.cl [Department of Mining Engineering, Universidad de La Serena (Chile); Centro de Estudios Avanzados en Zonas Aridas, La Serena (Chile)

2017-05-15

Environmental Impact Assessment (EIA) aims to determine if the environmental effect of an activity or project complies with standards and regulations. A primary component of the environment to evaluate is air and the effect that various activities can have on its quality. To this end, emission factors (EFs), which are empirical coefficients or mathematical relationships, are normally used. The present research critically analyzes the implications and consequences of using imported EFs in environmental impact studies (EISs), taking as case of study the situation in Chile. Among the main results, the widespread use of EFs in EISs in the country and the lack of assessments of their actual applicability stand out. In addition, the official guidelines related to emissions estimation that are used for EIA in the country mostly include EFs derived elsewhere, without considering the recommendations or restrictions that the original sources indicate for their use. Finally, the broad use of default values defined for the Metropolitan Region in Central Chile, is highly questionable for a country that extends north-south along more than 35° of latitude, with wide variability in climate, traffic conditions, population, soil types, etc. Finally, it is very likely that situations similar to those observed in the present work occurs in other countries with young environmental impact assessment systems, and therefore, that the results herein presented should be of general interest and relevance. - Highlights: • Emission factors are widely used in environmental impact assessment in Chile. • There is a lack of a proper understanding of the limitations of EFs for EIA. • Imported emission factors use requires caution and full understanding. • Misuse of foreign EFs may have serious environmental and economic consequences.

Life Cycle Building Carbon Emissions Assessment and Driving Factors Decomposition Analysis Based on LMDI—A Case Study of Wuhan City in China

Directory of Open Access Journals (Sweden)

Yuanyuan Gong

2015-12-01

Full Text Available Carbon emissions calculation at the sub-provincial level has issues in limited data and non-unified measurements. This paper calculated the life cycle energy consumption and carbon emissions of the building industry in Wuhan, China. The findings showed that the proportion of carbon emissions in the construction operation phase was the largest, followed by the carbon emissions of the indirect energy consumption and the construction material preparation phase. With the purpose of analyzing the contributors of the construction carbon emissions, this paper conducted decomposition analysis using Logarithmic Mean Divisia Index (LMDI. The results indicated that the increasing buidling area was the major driver of energy consumption and carbon emissions increase, followed by the behavior factor. Population growth and urbanization, to some extent, increased the carbon emissions as well. On the contrary, energy efficiency was the main inhibitory factor for reducing the carbon emissions. Policy implications in terms of low-carbon construction development were highlighted.

40 CFR 86.432-78 - Deterioration factor.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Deterioration factor. 86.432-78... 1978 and Later New Motorcycles, General Provisions § 86.432-78 Deterioration factor. (a) Deterioration factors shall be developed for each test vehicle from the emission test results. A separate factor shall...

Emissions, activity data, and emission factors of fluorinated greenhouse gases (F-Gases) in Germany 1995-2002

Energy Technology Data Exchange (ETDEWEB)

Schwarz, Winfried [Oeko-Recherche, Buero fuer Umweltforschung und -beratung GmbH, Frankfurt am Main (Germany)

2005-06-15

Before the 1997 Kyoto Protocol on Climate Protection, the fluorinated greenhouse gases HFCs, PFCs, and SF6 (F-gases) aroused little public attention. Since then, the standards on surveying and reporting on national emissions have been rising constantly. Amongst others, the annual reporting to the UNFCCC secretariat makes detailed declarations on use and emissions of F-gases necessary, which have to be filled in specified formats for submission (Common Reporting Format = CRF). The scientific basis has been set out by the UNFCCC guidelines on reporting, in accordance with the instructions laid down in IPCC good practice guidance. Additionally, in Germany the Centralised System of Emissions (ZSE) shall provide a suitable tool to satisfy any quality needs of both activity data and emission factors. From 1995 onwards, activity data and emissions of each individual application sector shall be presented in a comprehensible and transparent way. Therefore, the way of data collection as well as the estimation methods applied must be well documented. Moreover, data has to be prepared for appropriate importation into ZSE. It is the objective of this study to provide the transparency demanded within 40 national application sectors of F-gases, for the period between 1995 and 2002. - Firstly, all the activity data as well as the emissions related to them are presented and commented. This applies to manufacturing of products, F-gases banked in operating systems, and decommissioning. - Secondly, the methodologies applied to calculate the emissions are described and all sources of information are revealed, e.g. literature, names of experts from the manufacturing industry, users, trade, and academia. - Thirdly, reliability and safety of data are discussed. - Fourthly, possible deviations from the IPCC default values are stated and given reasons for. Wherever this intensive reviewing of 40 sectors through eight years of reporting uncovers gaps or inconsistencies in previous reports

Factors affecting ultraviolet-A photon emission from β-irradiated human keratinocyte cells.

Science.gov (United States)

Le, M; Mothersill, C E; Seymour, C B; Ahmad, S B; Armstrong, A; Rainbow, A J; McNeill, F E

2015-08-21

The luminescence intensity of 340±5 nm photons emitted from HaCaT (human keratinocyte) cells was investigated using a single-photon-counting system during cellular exposure to (90)Y β-particles. Multiple factors were assessed to determine their influence upon the quantity and pattern of photon emission from β-irradiated cells. Exposure of 1 x 10(4) cells/5 mL to 703 μCi resulted in maximum UVA photoemission at 44.8 x 10(3)±2.5 x 10(3) counts per second (cps) from live HaCaT cells (background: 1-5 cps); a 16-fold increase above cell-free controls. Significant biophoton emission was achieved only upon stimulation and was also dependent upon presence of cells. UVA luminescence was measured for (90)Y activities 14 to 703 μCi where a positive relationship between photoemission and (90)Y activity was observed. Irradiation of live HaCaT cells plated at various densities produced a distinct pattern of emission whereby luminescence increased up to a maximum at 1 x 10(4) cells/5 mL and thereafter decreased. However, this result was not observed in the dead cell population. Both live and dead HaCaT cells were irradiated and were found to demonstrate different rates of photon emission at low β activities (⩽400 μCi). Dead cells exhibited greater photon emission rates than live cells which may be attributable to metabolic processes taking place to modulate the photoemissive effect. The results indicate that photon emission from HaCaT cells is perturbed by external stimulation, is dependent upon the activity of radiation delivered, the density of irradiated cells, and cell viability. It is postulated that biophoton emission may be modulated by a biological or metabolic process.

X-RAY ABSORPTION, NUCLEAR INFRARED EMISSION, AND DUST COVERING FACTORS OF AGNs: TESTING UNIFICATION SCHEMES

Energy Technology Data Exchange (ETDEWEB)

Mateos, S.; Carrera, F. J.; Alonso-Herrero, A.; Hernán-Caballero, A.; Barcons, X. [Instituto de Física de Cantabria (CSIC-Universidad de Cantabria), E-39005, Santander (Spain); Ramos, A. Asensio; Almeida, C. Ramos [Instituto de Astrofísica de Canarias, E-38205, La Laguna, Tenerife (Spain); Watson, M. G.; Blain, A. [Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom); Caccianiga, A.; Ballo, L. [INAF-Osservatorio Astronomico di Brera, via Brera 28, I-20121 Milano (Italy); Braito, V., E-mail: mateos@ifca.unican.es [INAF-Osservatorio Astronomico di Brera, Via Bianchi 46, I-23807 Merate (Italy)

2016-03-10

We present the distributions of the geometrical covering factors of the dusty tori (f{sub 2}) of active galactic nuclei (AGNs) using an X-ray selected complete sample of 227 AGNs drawn from the Bright Ultra-hard XMM-Newton Survey. The AGNs have z from 0.05 to 1.7, 2–10 keV luminosities between 10{sup 42} and 10{sup 46} erg s{sup −1}, and Compton-thin X-ray absorption. Employing data from UKIDSS, 2MASS, and the Wide-field Infrared Survey Explorer in a previous work, we determined the rest-frame 1–20 μm continuum emission from the torus, which we model here with the clumpy torus models of Nenkova et al. Optically classified type 1 and type 2 AGNs are intrinsically different, with type 2 AGNs having, on average, tori with higher f{sub 2} than type 1 AGNs. Nevertheless, ∼20% of type 1 AGNs have tori with large covering factors, while ∼23%–28% of type 2 AGNs have tori with small covering factors. Low f{sub 2} are preferred at high AGN luminosities, as postulated by simple receding torus models, although for type 2 AGNs the effect is certainly small. f{sub 2} increases with the X-ray column density, which implies that dust extinction and X-ray absorption take place in material that share an overall geometry and most likely belong to the same structure, the putative torus. Based on our results, the viewing angle, AGN luminosity, and also f{sub 2} determine the optical appearance of an AGN and control the shape of the rest-frame ∼1–20 μm nuclear continuum emission. Thus, the torus geometrical covering factor is a key ingredient of unification schemes.

Identifying key factors and strategies for reducing industrial CO2 emissions from a non-Kyoto protocol member's (Taiwan) perspective

International Nuclear Information System (INIS)

Lin, Sue J.; Lu, I.J.; Lewis, Charles

2006-01-01

In this study we use Divisia index approach to identify key factors affecting CO 2 emission changes of industrial sectors in Taiwan. The changes of CO 2 emission are decomposed into emission coefficient, energy intensity, industrial structure and economic growth. Furthermore, comparisons with USA, Japan, Germany, the Netherlands and South Korea are made to have a better understanding of emission tendency in these countries and to help formulate our CO 2 reduction strategies for responding to the international calls for CO 2 cuts. The results show that economic growth and high energy intensity were two key factors for the rapid increase of industrial CO 2 emission in Taiwan, while adjustment of industrial structure was the main component for the decrease. Although economic development is important, Taiwan must keep pace with the international trends for CO 2 reduction. Among the most important strategies are continuous efforts to improve energy intensity, fuel mix toward lower carbon, setting targets for industrial CO 2 cuts, and advancing green technology through technology transfer. Also, the clean development mechanism (CDM) is expected to play an important role in the future

Estimation of the self-attenuation correction factor for gamma rays emission from nuclear materials

International Nuclear Information System (INIS)

Badawy, A.; El-Gammal, W.A.

2001-01-01

This work presents an investigation of the self-attenuation of gamma-rays emission from nuclear materials (NMs) for measuring the U-235 enrichment, U-235 mass content and isotopic composition of NMs by non-destructive assay technique [NDA]. The measurements then would not need the use of suitable NM Standards which may not be available in many situations. The self-attenuation correction factor (F) may be estimated by the use of the linear attenuation factor of the assayed sample, the geometrical configuration of the assay set-up and the position of the assayed sample relative to the detector. A developed mathematical analysis makes use of specific parameters which affect the estimation of the self-attenuation of the source-detector system which emits passive gamma-rays at certain prominent signatures

What factors influence mitigative capacity?

International Nuclear Information System (INIS)

Winkler, Harald; Baumert, Kevin; Blanchard, Odile; Burch, Sarah; Robinson, John

2007-01-01

This article builds on Yohe's seminal piece on mitigative capacity, which elaborates 'determinants' of mitigative capacity, also reflected in the IPCC's third assessment report. We propose a revised definition, where mitigative capacity is a country's ability to reduce anthropogenic greenhouse gas emissions or enhance natural sinks. By 'ability' we mean skills, competencies, fitness, and proficiencies that a country has attained which can contribute to GHG emissions mitigation. A conceptual framework is proposed, linking mitigative capacity to a country's sustainable development path, and grouping the factors influencing mitigative capacity into three main sets: economic factors, institutional ones, and technology. Both quantitative and qualitative analysis of factors is presented, showing how these factors vary across countries. We suggest that it is the interplay between the three economic factors-income, abatement cost and opportunity cost-that shape mitigative capacity. We find that income is an important economic factor influencing mitigative capacity, while abatement cost is important in turning mitigative capacity into actual mitigation. Technology is a critical mitigative capacity, including the ability to absorb existing climate-friendly technologies or to develop innovative ones. Institutional factors that promote mitigative capacity include the effectiveness of government regulation, clear market rules, a skilled work force and public awareness. We briefly investigate such as high abatement cost or lack of political willingness that prevent mitigative capacity from being translated into mitigation

Nitrous oxide exchanges with the atmosphere of a constructed wetland treating wastewater. Parameters and implications for emission factors

International Nuclear Information System (INIS)

Johansson, A.E.; Svenssom, B.H.; Kasimir Klemedtsson, Aa.; Klemedtsson, L.

2003-01-01

Static chamber measurements of N 2 O fluxes were taken during the 1998 and 1999 growth seasons in a Swedish constructed wetland receiving wastewater. The dominating plant species in different parts of the wetland were Lemna minor L., Typha latifolia L., Spirogyra sp. and Glyceria maxima (Hartm.) and Phalaris arundinacea (L.), respectively. There were large temporal and spatial variations in N 2 O fluxes, which ranged from consumption at -350 to emissions at 1791 μg N 2 O/m 2 /h. The largest positive flux occurred in October 1999 and the lowest in the middle of July 1999. The average N 2 O flux for the two years was 130 μg N 2 O/m 2 /h (SD = 220). No significant differences in N 2 O fluxes were found between the years, even though the two growing seasons differed considerably with respect to both air temperature and precipitation. 15% of the fluxes were negative, showing a consumption of N 2 O. Consumption occurred on a few occasions at most measurement sites and ranged from 1 - 350 μg N 2 O/m 2 /h. 13 - 43% of the variation in N 2 O fluxes was explained by multiple linear regression analysis including principal components. Emission factors were calculated according to IPCC methods from the N 2 O fluxes in the constructed wetland. The calculated emission factors were always lower (0.02 - 0.27%) compared to the default factor provided by the IPCC (0.75%). Thus, direct application of the IPCC default factor may lead to overestimation of N 2 O fluxes from constructed wastewater-treating wetlands

[Mercury Distribution Characteristics and Atmospheric Mercury Emission Factors of Typical Waste Incineration Plants in Chongqing].

Science.gov (United States)

Duan, Zhen-ya; Su, Hai-tao; Wang, Feng-yang; Zhang, Lei; Wang, Shu-xiao; Yu, Bin

2016-02-15

Waste incineration is one of the important atmospheric mercury emission sources. The aim of this article is to explore the atmospheric mercury pollution level of waste incineration industry from Chongqing. This study investigated the mercury emissions from a municipal solid waste incineration plant and a medical waste incineration plant in Chongqing. The exhaust gas samples in these two incineration plants were obtained using USA EPA 30B method. The mercury concentrations in the fly ash and bottom ash samples were analyzed. The results indicated that the mercury concentrations of the municipal solid waste and medical waste incineration plant in Chongqing were (26.4 +/- 22.7) microg x m(-3) and (3.1 +/- 0.8) microg x m(-3) in exhaust gas respectively, (5279.2 +/- 798.0) microg x kg(-1) and (11,709.5 +/- 460.5) microg x kg(-1) in fly ash respectively. Besides, the distribution proportions of the mercury content from municipal solid waste and medical waste in exhaust gas, fly ash, and bottom ash were 34.0%, 65.3%, 0.7% and 32.3%, 67.5%, 0.2% respectively; The mercury removal efficiencies of municipal solid waste and medical waste incineration plants were 66.0% and 67.7% respectively. The atmospheric mercury emission factors of municipal solid waste and medical waste incineration plants were (126.7 +/- 109.0) microg x kg(-1) and (46.5 +/- 12.0) microg x kg(-1) respectively. Compared with domestic municipal solid waste incineration plants in the Pearl River Delta region, the atmospheric mercury emission factor of municipal solid waste incineration plant in Chongqing was lower.

Techniques for Estimating Emissions Factors from Forest Burning: ARCTAS and SEAC4RS Airborne Measurements Indicate which Fires Produce Ozone

Science.gov (United States)

Chatfield, Robert B.; Andreae, Meinrat O.

2016-01-01

Previous studies of emission factors from biomass burning are prone to large errors since they ignore the interplay of mixing and varying pre-fire background CO2 levels. Such complications severely affected our studies of 446 forest fire plume samples measured in the Western US by the science teams of NASA's SEAC4RS and ARCTAS airborne missions. Consequently we propose a Mixed Effects Regression Emission Technique (MERET) to check techniques like the Normalized Emission Ratio Method (NERM), where use of sequential observations cannot disentangle emissions and mixing. We also evaluate a simpler "consensus" technique. All techniques relate emissions to fuel burned using C(burn) = delta C(tot) added to the fire plume, where C(tot) approximately equals (CO2 = CO). Mixed-effects regression can estimate pre-fire background values of C(tot) (indexed by observation j) simultaneously with emissions factors indexed by individual species i, delta, epsilon lambda tau alpha-x(sub I)/C(sub burn))I,j. MERET and "consensus" require more than emissions indicators. Our studies excluded samples where exogenous CO or CH4 might have been fed into a fire plume, mimicking emission. We sought to let the data on 13 gases and particulate properties suggest clusters of variables and plume types, using non-negative matrix factorization (NMF). While samples were mixtures, the NMF unmixing suggested purer burn types. Particulate properties (b scant, b abs, SSA, AAE) and gas-phase emissions were interrelated. Finally, we sought a simple categorization useful for modeling ozone production in plumes. Two kinds of fires produced high ozone: those with large fuel nitrogen as evidenced by remnant CH3CN in the plumes, and also those from very intense large burns. Fire types with optimal ratios of delta-NOy/delta- HCHO associate with the highest additional ozone per unit Cburn, Perhaps these plumes exhibit limited NOx binding to reactive organics. Perhaps these plumes exhibit limited NOx binding to

Size-resolved particle number emission patterns under real-world driving conditions using positive matrix factorization.

Science.gov (United States)

Domínguez-Sáez, Aida; Viana, Mar; Barrios, Carmen C; Rubio, Jose R; Amato, Fulvio; Pujadas, Manuel; Querol, Xavier

2012-10-16

A novel on-board system was tested to characterize size-resolved particle number emission patterns under real-world driving conditions, running in a EURO4 diesel vehicle and in a typical urban circuit in Madrid (Spain). Emission profiles were determined as a function of driving conditions. Source apportionment by Positive Matrix Factorization (PMF) was carried out to interpret the real-world driving conditions. Three emission patterns were identified: (F1) cruise conditions, with medium-high speeds, contributing in this circuit with 60% of total particle number and a particle size distribution dominated by particles >52 nm and around 60 nm; (F2) transient conditions, stop-and-go conditions at medium-high speed, contributing with 25% of the particle number and mainly emitting particles in the nucleation mode; and (F3) creep-idle conditions, representing traffic congestion and frequent idling periods, contributing with 14% to the total particle number and with particles in the nucleation mode (emissions depending on particle size and driving conditions. Differences between real-world emission patterns and regulatory cycles (NEDC) are also presented, which evidence that detecting particle number emissions real-world driving conditions.

Examination of Environmental Factors Influencing the Emission Rates of Semivolatile Organic Compounds

Directory of Open Access Journals (Sweden)

Sunwoo Lee

2018-01-01

Full Text Available Some types of semivolatile organic compounds (SVOCs that are emitted from plastics used in building materials and household appliances have been associated with health risks, even at low concentrations. It has been reported that di-2-ethylhexyl phthalate (DEHP—one of the most commonly used plasticizers—causes asthma and allergic symptoms in children at home. The amount of emitted DEHP, which is classified as a SVOC, can be measured using a microchamber by the thermal desorption test chamber method. To accurately measure the SVOC emission rates, the relation between SVOC and environmental factors should be clarified. Herein, we examined the effects of the temperature, relative humidity, concentration of airborne particles, and flow field in the microchamber on SVOC emission rates. The flow fields inside the microchamber were analyzed via computational fluid dynamics (CFD. The emission rate of SVOC released from PVC flooring increased under high temperatures and at high concentrations of airborne particles but did not depend on the relative humidity. From an evaluation performed using an index of air change efficiency, such as the air age and the coefficient of air change performance, we found that a fixed air exchange rate of 1.5 h−1 in the microchamber is desirable.

Non-relativistic Free–Free Emission due to the n -distribution of Electrons—Radiative Cooling and Thermally Averaged and Total Gaunt Factors

Energy Technology Data Exchange (ETDEWEB)

De Avillez, Miguel A. [Department of Mathematics, University of Évora, R. Romão Ramalho 59, 7000 Évora (Portugal); Breitschwerdt, Dieter, E-mail: mavillez@galaxy.lca.uevora.pt [Zentrum für Astronomie und Astrophysik, Technische Universität Berlin, Hardenbergstrasse 36, D-10623 Berlin (Germany)

2017-09-01

Tracking the thermal evolution of plasmas, characterized by an n -distribution, using numerical simulations, requires the determination of the emission spectra and of the radiative losses due to free–free emission from the corresponding temperature-averaged and total Gaunt factors. Detailed calculations of the latter are presented and associated with n -distributed electrons with the parameter n ranging from 1 (corresponding to the Maxwell–Boltzmann distribution) to 100. The temperature-averaged and total Gaunt factors with decreasing n tend toward those obtained with the Maxwell–Boltzmann distribution. Radiative losses due to free–free emission in a plasma evolving under collisional ionization equilibrium conditions and composed by H, He, C, N, O, Ne, Mg, Si, S, and Fe ions, are presented. These losses decrease with a decrease in the parameter n , reaching a minimum when n  = 1, and thus converge with the loss of thermal plasma. Tables of the thermal-averaged and total Gaunt factors calculated for n -distributions, and a wide range of electron and photon energies, are presented.

Non-relativistic Free–Free Emission due to the n -distribution of Electrons—Radiative Cooling and Thermally Averaged and Total Gaunt Factors

International Nuclear Information System (INIS)

De Avillez, Miguel A.; Breitschwerdt, Dieter

2017-01-01

Tracking the thermal evolution of plasmas, characterized by an n -distribution, using numerical simulations, requires the determination of the emission spectra and of the radiative losses due to free–free emission from the corresponding temperature-averaged and total Gaunt factors. Detailed calculations of the latter are presented and associated with n -distributed electrons with the parameter n ranging from 1 (corresponding to the Maxwell–Boltzmann distribution) to 100. The temperature-averaged and total Gaunt factors with decreasing n tend toward those obtained with the Maxwell–Boltzmann distribution. Radiative losses due to free–free emission in a plasma evolving under collisional ionization equilibrium conditions and composed by H, He, C, N, O, Ne, Mg, Si, S, and Fe ions, are presented. These losses decrease with a decrease in the parameter n , reaching a minimum when n  = 1, and thus converge with the loss of thermal plasma. Tables of the thermal-averaged and total Gaunt factors calculated for n -distributions, and a wide range of electron and photon energies, are presented.

Emission factors of air pollutants from CNG-gasoline bi-fuel vehicles: Part I. Black carbon.

Science.gov (United States)

Wang, Yang; Xing, Zhenyu; Xu, Hui; Du, Ke

2016-12-01

Compressed natural gas (CNG) is considered to be a "cleaner" fuel compared to other fossil fuels. Therefore, it is used as an alternative fuel in motor vehicles to reduce emissions of air pollutants in transportation. To quantify "how clean" burning CNG is compared to burning gasoline, quantification of pollutant emissions under the same driving conditions for motor vehicles with different fuels is needed. In this study, a fleet of bi-fuel vehicles was selected to measure the emissions of black carbon (BC), carbon monoxide (CO), hydrocarbon (HC) and nitrogen oxide (NO x ) for driving in CNG mode and gasoline mode respectively under the same set of constant speeds and accelerations. Comparison of emission factors (EFs) for the vehicles burning CNG and gasoline are discussed. This part of the paper series reports BC EFs for bi-fuel vehicles driving on the real road, which were measured using an in situ method. Our results show that burning CNG will lead to 54%-83% reduction in BC emissions per kilometer, depending on actual driving conditions. These comparisons show that CNG is a cleaner fuel than gasoline for motor vehicles in terms of BC emissions and provide a viable option for reducing BC emissions cause by transportation. Copyright © 2016 Elsevier B.V. All rights reserved.

Factors controlling regional differences in forest soil emission of nitrogen oxides (NO and N2O

Directory of Open Access Journals (Sweden)

K. Pilegaard

2006-01-01

Full Text Available Soil emissions of NO and N2O were measured continuously at high frequency for more than one year at 15 European forest sites as part of the EU-funded project NOFRETETE. The locations represent different forest types (coniferous/deciduous and different nitrogen loads. Geographically they range from Finland in the north to Italy in the south and from Hungary in the east to Scotland in the west. The highest NO emissions were observed from coniferous forests, whereas the lowest NO emissions were observed from deciduous forests. The NO emissions from coniferous forests were highly correlated with N-deposition. The site with the highest average annual emission (82 μg NO-N m−2 h−1 was a spruce forest in South-Germany (Höglwald receiving an annual N-deposition of 2.9 g m−2. NO emissions close to the detection limit were observed from a pine forest in Finland where the N-deposition was 0.2 g N m−2 a−1. No significant correlation between N2O emission and N-deposition was found. The highest average annual N2O emission (20 μg N2O-N m−2 h−1 was found in an oak forest in the Mátra mountains (Hungary receiving an annual N-deposition of 1.6 g m−2. N2O emission was significantly negatively correlated with the C/N ratio. The difference in N-oxide emissions from soils of coniferous and deciduous forests may partly be explained by differences in N-deposition rates and partly by differences in characteristics of the litter layer and soil. NO was mainly derived from nitrification whereas N2O was mainly derived from denitrification. In general, soil moisture is lower at coniferous sites (at least during spring time and the litter layer of coniferous forests is thick and well aerated favouring nitrification and thus release of NO. Conversely, the higher rates of denitrification in deciduous forests due to a compact and moist litter layer lead to N2O production and NO consumption in the soil. The two factors soil moisture and soil temperature are

Nitrous oxide exchanges with the atmosphere of a constructed wetland treating wastewater. Parameters and implications for emission factors

Energy Technology Data Exchange (ETDEWEB)

Johansson, A.E.; Svenssom, B.H. [Linkoeing Univ. (Sweden). Dept. of Water and Environmental Studies; Kasimir Klemedtsson, Aa. [Trollhaettan/Uddevalla Univ. College, Trollhaettan (Sweden). Dept. of Informatics and Mathematics; Klemedtsson, L. [Goeteborg Univ. (Sweden). Botanical Inst.

2003-07-01

Static chamber measurements of N{sub 2}O fluxes were taken during the 1998 and 1999 growth seasons in a Swedish constructed wetland receiving wastewater. The dominating plant species in different parts of the wetland were Lemna minor L., Typha latifolia L., Spirogyra sp. and Glyceria maxima (Hartm.) and Phalaris arundinacea (L.), respectively. There were large temporal and spatial variations in N{sub 2}O fluxes, which ranged from consumption at -350 to emissions at 1791 {mu}g N{sub 2}O/m{sup 2}/h. The largest positive flux occurred in October 1999 and the lowest in the middle of July 1999. The average N{sub 2}O flux for the two years was 130 {mu}g N{sub 2}O/m{sup 2}/h (SD = 220). No significant differences in N{sub 2}O fluxes were found between the years, even though the two growing seasons differed considerably with respect to both air temperature and precipitation. 15% of the fluxes were negative, showing a consumption of N{sub 2}O. Consumption occurred on a few occasions at most measurement sites and ranged from 1 - 350 {mu}g N{sub 2}O/m{sup 2}/h. 13 - 43% of the variation in N{sub 2}O fluxes was explained by multiple linear regression analysis including principal components. Emission factors were calculated according to IPCC methods from the N{sub 2}O fluxes in the constructed wetland. The calculated emission factors were always lower (0.02 - 0.27%) compared to the default factor provided by the IPCC (0.75%). Thus, direct application of the IPCC default factor may lead to overestimation of N{sub 2}O fluxes from constructed wastewater-treating wetlands.

Application of positive matrix factorization to on-road measurements for source apportionment of diesel- and gasoline-powered vehicle emissions in Mexico City

Directory of Open Access Journals (Sweden)

D. A. Thornhill

2010-04-01

Full Text Available The goal of this research is to quantify diesel- and gasoline-powered motor vehicle emissions within the Mexico City Metropolitan Area (MCMA using on-road measurements captured by a mobile laboratory combined with positive matrix factorization (PMF receptor modeling. During the MCMA-2006 ground-based component of the MILAGRO field campaign, the Aerodyne Mobile Laboratory (AML measured many gaseous and particulate pollutants, including carbon dioxide, carbon monoxide (CO, nitrogen oxides (NO_x, benzene, toluene, alkylated aromatics, formaldehyde, acetaldehyde, acetone, ammonia, particle number, fine particulate mass (PM_2.5, and black carbon (BC. These serve as inputs to the receptor model, which is able to resolve three factors corresponding to gasoline engine exhaust, diesel engine exhaust, and the urban background. Using the source profiles, we calculate fuel-based emission factors for each type of exhaust. The MCMA's gasoline-powered vehicles are considerably dirtier, on average, than those in the US with respect to CO and aldehydes. Its diesel-powered vehicles have similar emission factors of NO_x and higher emission factors of aldehydes, particle number, and BC. In the fleet sampled during AML driving, gasoline-powered vehicles are found to be responsible for 97% of total vehicular emissions of CO, 22% of NO_x, 95–97% of each aromatic species, 72–85% of each carbonyl species, 74% of ammonia, negligible amounts of particle number, 26% of PM_2.5, and 2% of BC; diesel-powered vehicles account for the balance. Because the mobile lab spent 17% of its time waiting at stoplights, the results may overemphasize idling conditions, possibly resulting in an underestimate of NO_x and overestimate of CO emissions. On the other hand, estimates of the inventory that do not correctly account for emissions during idling are likely to produce bias in the opposite direction.The resulting fuel

Are emissions of black carbon from gasoline vehicles overestimated? Real-time, in situ measurement of black carbon emission factors.

Science.gov (United States)

Wang, Yang; Xing, Zhenyu; Zhao, Shuhui; Zheng, Mei; Mu, Chao; Du, Ke

2016-03-15

Accurately quantifying black carbon (BC) emission factors (EFs) is a prerequisite for estimation of BC emission inventory. BC EFs determined by measuring BC at the roadside or chasing a vehicle on-road may introduce large uncertainty for low emission vehicles. In this study, BC concentrations were measured inside the tailpipe of gasoline vehicles with different engine sizes under different driving modes to determine the respective EFs. BC EFs ranged from 0.005-7.14 mg/kg-fuel under the speeds of 20-70 km/h, 0.05-28.95 mg/kg-fuel under the accelerations of 0.5-1.5m/s(2). Although the water vapor in the sampling stream could result in an average of 12% negative bias, the BC EFs are significantly lower than the published results obtained with roadside or chasing vehicle measurement. It is suggested to conduct measurement at the tailpipe of gasoline vehicles instead of in the atmosphere behind the vehicles to reduce the uncertainty from fluctuation in ambient BC concentration. Copyright © 2015 Elsevier B.V. All rights reserved.

Field determination of multipollutant, open area combustion source emission factors with a hexacopter unmanned aerial vehicle

Science.gov (United States)

Aurell, J.; Mitchell, W.; Chirayath, V.; Jonsson, J.; Tabor, D.; Gullett, B.

2017-10-01

An emission sensor/sampler system was coupled to a National Aeronautics and Space Administration (NASA) hexacopter unmanned aerial vehicle (UAV) to characterize gases and particles in the plumes emitted from open burning of military ordnance. The UAV/sampler was tested at two field sites with test and sampling flights spanning over 16 h of flight time. The battery-operated UAV was remotely maneuvered into the plumes at distances from the pilot of over 600 m and at altitudes of up to 122 m above ground level. While the flight duration could be affected by sampler payload (3.2-4.6 kg) and meteorological conditions, the 57 sampling flights, ranging from 4 to 12 min, were typically terminated when the plume concentrations of CO2 were diluted to near ambient levels. Two sensor/sampler systems, termed ;Kolibri,; were variously configured to measure particulate matter, metals, chloride, perchlorate, volatile organic compounds, chlorinated dioxins/furans, and nitrogen-based organics for determination of emission factors. Gas sensors were selected based on their applicable concentration range, light weight, freedom from interferents, and response/recovery times. Samplers were designed, constructed, and operated based on U.S. Environmental Protection Agency (EPA) methods and quality control criteria. Results show agreement with published emission factors and good reproducibility (e.g., 26% relative standard deviation for PM2.5). The UAV/Kolibri represents a significant advance in multipollutant emission characterization capabilities for open area sources, safely and effectively making measurements heretofore deemed too hazardous for personnel or beyond the reach of land-based samplers.

Factors affecting temporal H2S emission at construction and demolition (C&D) debris landfills.

Science.gov (United States)

Xu, Qiyong; Townsend, Timothy

2014-02-01

Odor problems associated with H2S emissions often result in odor complaints from nearby residents of C&D debris landfills, especially in the early morning. As part of a field study conducted on H2S removal ability using different cover materials, daily and seasonal H2S emissions through a soil cover layer were monitored at a C&D debris landfill to investigate factors affecting H2S emissions. H2S emission rates were not a constant, but varied seasonally, with an average emission rate of 4.67×10(-6)mgm(-2)s(-1). During a the 10-month field study, as the H2S concentration increased from 140ppm to about 3500ppm underneath the cover soil in the testing cell, H2S emissions ranged from zero to a maximum emission rate of 1.24×10(-5)mgm(-2)s(-1). Continuous emission monitoring indicated that H2S emissions even changed over time throughout the day, generally increasing from morning to afternoon, and were affected by soil moisture and temperature. Laboratory experiments were also conducted to investigate the effects of H2S concentration and cover soil moisture content on H2S emissions. The results showed that increased soil moisture reduced H2S emissions by retarding H2S migration through cover soil and dissolving H2S into soil water. The field study also indicated that due to atmospheric dispersion, high H2S emissions may not cause odor problems. Copyright © 2013 Elsevier Ltd. All rights reserved.

Nitrogen oxide emission calculation for post-Panamax container ships by using engine operation power probability as weighting factor: A slow-steaming case.

Science.gov (United States)

Cheng, Chih-Wen; Hua, Jian; Hwang, Daw-Shang

2017-12-07

In this study, the nitrogen oxide (NO x ) emission factors and total NO x emissions of two groups of post-Panamax container ships operating on a long-term slow-steaming basis along Euro-Asian routes were calculated using both the probability density function of engine power levels and the NO x emission function. The main engines of the five sister ships in Group I satisfied the Tier I emission limit stipulated in MARPOL (International Convention for the Prevention of Pollution from Ships) Annex VI, and those in Group II satisfied the Tier II limit. The calculated NO x emission factors of the Group I and Group II ships were 14.73 and 17.85 g/kWhr, respectively. The total NO x emissions of the Group II ships were determined to be 4.4% greater than those of the Group I ships. When the Tier II certification value was used to calculate the average total NO x emissions of Group II engines, the result was lower than the actual value by 21.9%. Although fuel consumption and carbon dioxide (CO 2 ) emissions were increased by 1.76% because of slow steaming, the NO x emissions were markedly reduced by 17.2%. The proposed method is more effective and accurate than the NO x Technical Code 2008. Furthermore, it can be more appropriately applied to determine the NO x emissions of international shipping inventory. The usage of operating power probability density function of diesel engines as the weighting factor and the NO x emission function obtained from test bed for calculating NO x emissions is more accurate and practical. The proposed method is suitable for all types and purposes of diesel engines, irrespective of their operating power level. The method can be used to effectively determine the NO x emissions of international shipping and inventory applications and should be considered in determining the carbon tax to be imposed in the future.

Aerosol and NOx emission factors and submicron particle number size distributions in two road tunnels with different traffic regimes

Directory of Open Access Journals (Sweden)

D. Imhof

2006-01-01

Full Text Available Measurements of aerosol particle number size distributions (18–700 nm, mass concentrations (PM2.5 and PM10 and NOx were performed in the Plabutsch tunnel, Austria, and in the Kingsway tunnel, United Kingdom. These two tunnels show different characteristics regarding the roadway gradient, the composition of the vehicle fleet and the traffic frequency. The submicron particle size distributions contained a soot mode in the diameter range D=80–100 nm and a nucleation mode in the range of D=20–40 nm. In the Kingsway tunnel with a significantly lower particle number and volume concentration level than in the Plabutsch tunnel, a clear diurnal variation of nucleation and soot mode particles correlated to the traffic density was observed. In the Plabutsch tunnel, soot mode particles also revealed a diurnal variation, whereas no substantial variation was found for the nucleation mode particles. During the night a higher number concentration of nucleation mode particles were measured than soot mode particles and vice versa during the day. In this tunnel with very high soot emissions during daytime due to the heavy-duty vehicle (HDV share of 18% and another 40% of diesel driven light-duty vehicles (LDV semivolatile species condense on the pre-existing soot surface area rather than forming new particles by homogeneous nucleation. With the low concentration of soot mode particles in the Kingsway tunnel, also the nucleation mode particles exhibit a diurnal variation. From the measured parameters real-world traffic emission factors were estimated for the whole vehicle fleet as well as differentiated into the two categories LDV and HDV. In the particle size range D=18–700 nm, each vehicle of the mixed fleet emits (1.50±0.08×1014 particles km-1 (Plabutsch and (1.26±0.10×1014 particles km-1 (Kingsway, while particle volume emission factors of 0.209±0.008 cm3 km-1 and 0.036±0.004 cm3 km-1, respectively, were obtained. PM1 emission factors of 104±4 mg

Revised (Mixed-Effects) Estimation for Forest Burning Emissions of Gases and Smoke, Fire/Emission Factor Typology, and Potential Remote Sensing Classification of Types for Ozone and Black-Carbon Simulation

Science.gov (United States)

Chatfield, Robert B.; Segal Rozenhaimer, M.

2014-01-01

We summarize recent progress (a) in correcting biomass burning emissions factors deduced from airborne sampling of forest fire plumes, (b) in understanding the variability in reactivity of the fresh plumes sampled in ARCTAS (2008), DC3 (2012), and SEAC4RS (2013) airborne missions, and (c) in a consequent search for remotely sensed quantities that help classify forest-fire plumes. Particle properties, chemical speciation, and smoke radiative properties are related and mutually informative, as pictures below suggest (slopes of lines of same color are similar). (a) Mixed-effects (random-effects) statistical modeling provides estimates of both emission factors and a reasonable description of carbon-burned simultaneously. Different fire plumes will have very different contributions to volatile organic carbon reactivity; this may help explain differences of free NOx(both gas- and particle-phase), and also of ozone production, that have been noted for forest-fire plumes in California. Our evaluations check or correct emission factors based on sequential measurements (e.g., the Normalized Ratio Enhancement and similar methods). We stress the dangers of methods relying on emission-ratios to CO. (b) This work confirms and extends many reports of great situational variability in emissions factors. VOCs vary in OH reactivity and NOx-binding. Reasons for variability are not only fuel composition, fuel condition, etc., but are confused somewhat by rapid transformation and mixing of emissions. We use "unmixing" (distinct from mixed-effects) statistics and compare briefly to approaches like neural nets. We focus on one particularly intense fire the notorious Yosemite Rim Fire of 2013. In some samples, NOx activity was not so suppressed by binding into nitrates as in other fires. While our fire-typing is evolving and subject to debate, the carbon-burned delta(CO2+CO) estimates that arise from mixed effects models, free of confusion by background-CO2 variation, should provide a

Studying the Impacts of Environmental Factors and Agricultural Management on Methane Emissions from Rice Paddies Using a Land Surface Model

Science.gov (United States)

Lin, T. S.; Gahlot, S.; Shu, S.; Jain, A. K.; Kheshgi, H. S.

2017-12-01

Continued growth in population is projected to drive increased future demand for rice and the methane emissions associated with its production. However, observational studies of methane emissions from rice have reported seemingly conflicting results and do not all support this projection. In this study we couple an ecophysiological process-based rice paddy module and a methane emission module with a land surface model, Integrated Science Assessment Model (ISAM), to study the impacts of various environmental factors and agricultural management practices on rice production and methane emissions from rice fields. This coupled modeling framework accounts for dynamic rice growth processes with adaptation of photosynthesis, rice-specific phenology, biomass accumulation, leaf area development and structures responses to water, temperature, light and nutrient stresses. The coupled model is calibrated and validated with observations from various rice cultivation fields. We find that the differing results of observational studies can be caused by the interactions of environmental factors, including climate, atmospheric CO2 concentration, and N deposition, and agricultural management practices, such as irrigation and N fertilizer applications, with rice production at spatial and temporal scales.

Field determination of biomass burning emission ratios and factors via open-path FTIR spectroscopy and fire radiative power assessment: headfire, backfire and residual smouldering combustion in African savannahs

CSIR Research Space (South Africa)

Wooster, MJ

2011-01-01

Full Text Available Biomass burning emissions factors are vital to quantifying trace gases releases from vegetation fires. Here the authors evaluate emissions factors for a series of savannah fires in Kruger National Park (KNP), South Africa using ground-based open...

Factors that determine the emission of gaseous and particle pollutants for the combustion of fossil fuels

International Nuclear Information System (INIS)

Bobadilla Edgar; Gomez Elias; Ramirez Beatriz

1997-01-01

The effect of physical-chemical, kinetic, estequiometric factors and of the mixture conditions on the emissions of five main classes of pollutants produced by the combustion equipments is analyzed. The emissions of monoxide of carbon (CO) are ruled by temperature and the proportion air - fuel. The production of nitrogen oxides (NOx) is determined by operation conditions (mainly temperature) and the composition of the fuel. The oxides of sulfur (SOx) are highly influenced by the temperature; in general, the formation of SO2 is faster than the oxidation of SO3. The temperature and the degree of homogenization of the mixture are decisive in the formation of organic volatile compounds. The emission of soot and fine ashes depends basically on the temperature, ratio air - fuel and conditions of homogenization of the mixture

Laboratory incubation experiments assessing the factor interactions affecting urine-derived nitrous oxide emissions from spatially and temporally variable upland pastures

Science.gov (United States)

Charteris, Alice; Loick, Nadine; Marsden, Karina; Chadwick, Dave; Whelan, Mick; Rao Ravella, Sreenivas; Mead, Andrew; Cardenas, Laura

2017-04-01

Urine patches deposited to soils by grazing animals represent hot-spots of nitrous oxide (N2O) emissions (Hargreaves et al., 2015), a powerful greenhouse gas (GHG) and precursor of ozone depletion in the stratosphere. Urine N2O emissions are produced via nitrification of ureolysis-derived ammonium (NH4+) and/or subsequent nitrite (NO2-) and nitrate (NO3-) denitrification (Kool et al., 2006). The dominant process and the N2O fluxes generated depend on interactions between urine characteristics (e.g. nitrogen [N] concentration and volume), soil characteristics (e.g. carbon [C] availability and pH) and preceding and prevailing environmental conditions (e.g. soil moisture and temperature; Bergstermann et al., 2011; Butterbach-Bahl et al., 2013; Dijkstra et al., 2013). The spatial and temporal variability of these interactions in grazing systems is potentially large and greatly increases the uncertainty associated with N2O emission estimates from such systems. In particular, the contribution of extensively managed upland agroecosystems, which occupy ca. 5.5 million hectares in the UK and provide the bulk of land for sheep farming (Pollott & Stone, 2004), to UK GHG emissions is poorly defined. Improving understanding of the interactions between the wide range of factors affecting urine-derived N2O production and emission from pasture soils and considering this in the context of the spatial and temporal variability of the grazing environment could therefore be extremely valuable in improving the accuracy of N2O emission estimates from such systems. The factorial laboratory incubation experiments presented have been designed to assess the interactive effects of factors such as urine N concentration, volume and soil moisture affecting soil N2O (and nitric oxide [NO], nitrogen gas [N2] and carbon dioxide [CO2]) production and emissions (García-Marco et al., 2014) using the state-of-the-art Denitrification Incubation System (DENIS). This work forms part of a wider project

Field determination of biomass burning emission ratios and factors via open-path FTIR spectroscopy and fire radiative power assessment: headfire, backfire and residual smouldering combustion in African savannahs

Directory of Open Access Journals (Sweden)

M. J. Wooster

2011-11-01

Full Text Available Biomass burning emissions factors are vital to quantifying trace gas release from vegetation fires. Here we evaluate emissions factors for a series of savannah fires in Kruger National Park (KNP, South Africa using ground-based open path Fourier transform infrared (FTIR spectroscopy and an IR source separated by 150–250 m distance. Molecular abundances along the extended open path are retrieved using a spectral forward model coupled to a non-linear least squares fitting approach. We demonstrate derivation of trace gas column amounts for horizontal paths transecting the width of the advected plume, and find for example that CO mixing ratio changes of ~0.01 μmol mol⁻¹ [10 ppbv] can be detected across the relatively long optical paths used here. Though FTIR spectroscopy can detect dozens of different chemical species present in vegetation fire smoke, we focus our analysis on five key combustion products released preferentially during the pyrolysis (CH₂O, flaming (CO₂ and smoldering (CO, CH₄, NH₃ processes. We demonstrate that well constrained emissions ratios for these gases to both CO₂ and CO can be derived for the backfire, headfire and residual smouldering combustion (RSC stages of these savannah fires, from which stage-specific emission factors can then be calculated. Headfires and backfires often show similar emission ratios and emission factors, but those of the RSC stage can differ substantially. The timing of each fire stage was identified via airborne optical and thermal IR imagery and ground-observer reports, with the airborne IR imagery also used to derive estimates of fire radiative energy (FRE, allowing the relative amount of fuel burned in each stage to be calculated and "fire averaged" emission ratios and emission factors to be determined. These "fire averaged" metrics are dominated by the headfire contribution, since the FRE data indicate that the vast majority

Influence of natural and anthropogenic factors on the dynamics of CO2 emissions from chernozems soil

Science.gov (United States)

Syabruk, Olesia

2017-04-01

Twentieth century marked a significant expansion of agricultural production. Soil erosion caused by human activity, conversion of forests and grasslands to cropland, desertification, burning nutrient residues, drainage, excessive cultivation led to intense oxidation of soil carbon to the atmosphere and allocation of additional amounts of CO2. According to the UN Intergovernmental Panel on Climate Change, agriculture is one of the main sources of greenhouse gases emissions to the atmosphere. The thesis reveals main patterns of the impact of natural and anthropogenic factors on CO2 emissions in the chernozems typical and podzolized in a Left-bank Forest-Steppe of Ukraine, seasonal and annual dynamics. New provisions for conducting monitoring CO2 emissions from soil were developed by combining observations in natural and controlled conditions, which allows isolating the impact of hydrological, thermal and trophic factors. During the research, the methods for operational monitoring of emission of carbon losses were improved, using a portable infrared gas analyzer, which allows receiving information directly in the field. It was determined that the volumes of emission losses of carbon chernozems typical and podzolized Left-bank Forest-Steppe of Ukraine during the growing season are 480-910 kg/ha and can vary depending on the soil treatment ±( 4,0 - 6,0) % and fertilizer systems ± (3,8 - 7,1) %. The significant impact of long application of various fertilizer systems and soil treatment on the intensity of carbon dioxide emissions was investigated. It was found that most emission occurs in organic- mineral fertilizers systems with direct seeding. The seasonal dynamics of the potential capacity of the soil to produce CO2 were researched. Under identical conditions of humidity and temperature it has maximum in June and July and the gradual extinction of the autumn. It was determined that the intensity of the CO2 emission from the surface of chernozem fluctuates daily from

Greenhouse gas emission factor for coal power chain in China and the comparison with nuclear power chain

International Nuclear Information System (INIS)

Ma Zhonghai; Pan Ziqiang; He Huimin

1999-01-01

The Greenhouse Gas Emission for coal power chain in China is analyzed in detail and comprehensively by using the Life Cycle Analysis method. The Greenhouse Gas Emission Factors (GGEF) in each link and for the total power chain are calculated. The total GGEF for coal power chain is 1302.3 gCO 2 /kWh, about 40 times more than that for nuclear power chain. And consequently greenhouse effect could not be aggravated further by nuclear power. The energy strategy for nuclear power development is one of reality ways to retard the greenhouse effect, put resources into rational use and protect environment

Monitoring organic loading to swimming pools by fluorescence excitation–emission matrix with parallel factor analysis (PARAFAC)

DEFF Research Database (Denmark)

Seredynska-Sobecka, Bozena; Stedmon, Colin; Boe-Hansen, Rasmus

2011-01-01

Fluorescence Excitation–Emission Matrix spectroscopy combined with parallel factor analysis was employed to monitor water quality and organic contamination in swimming pools. The fluorescence signal of the swimming pool organic matter was low but increased slightly through the day. The analysis...... revealed that the organic matter fluorescence was characterised by five different components, one of which was unique to swimming pool organic matter and one which was specific to organic contamination. The latter component had emission peaks at 420nm and was found to be a sensitive indicator of organic...... loading in swimming pool water. The fluorescence at 420nm gradually increased during opening hours and represented material accumulating through the day....

A laboratory comparison of emission factors, number size distributions and morphology of ultrafine particles from eleven different household cookstove-fuel systems

Data.gov (United States)

U.S. Environmental Protection Agency — This dataset includes all data used to generate figures in the manuscript and supporting information for the publication entitled "Emission factors, number size...

Factors Affecting Aerosol Radiative Forcing

Science.gov (United States)

Wang, J.; Lin, J.; Ni, R.

2016-12-01

Rapid industrial and economic growth has meant large amount of aerosols in the atmosphere with strong radiative forcing (RF) upon the climate system. Over parts of the globe, the negative forcing of aerosols has overcompensated for the positive forcing of greenhouse gases. Aerosol RF is determined by emissions and various chemical-transport-radiative processes in the atmosphere, a multi-factor problem whose individual contributors have not been well quantified. In this study, we analyze the major factors affecting RF of secondary inorganic aerosols (SIOAs, including sulfate, nitrate and ammonium), primary organic aerosol (POA), and black carbon (BC). We analyze the RFof aerosols produced by 11 major regions across the globe, including but not limited to East Asia, Southeast Asia, South Asia, North America, and Western Europe. Factors analyzed include population size, per capita gross domestic production (GDP), emission intensity (i.e., emissionsper unit GDP), chemical efficiency (i.e., mass per unit emissions) and radiative efficiency (i.e., RF per unit mass). We find that among the 11 regions, East Asia produces the largest emissions and aerosol RF, due to relatively high emission intensity and a tremendous population size.South Asia produce the second largest RF of SIOA and BC and the highest RF of POA, in part due to its highest chemical efficiency among all regions. Although Southeast Asia also has large emissions,its aerosol RF is alleviated by its lowest chemical efficiency.The chemical efficiency and radiative efficiency of BC produced by the Middle East-North Africa are the highest across the regions, whereas its RF is loweredbyasmall per capita GDP.Both North America and Western Europe have low emission intensity, compensating for the effects on RF of large population sizes and per capita GDP. There has been a momentum to transfer industries to Southeast Asia and South Asia, and such transition is expected to continue in the coming years. The resulting

3Ecologies: Visualizing sustainability factors and futures

OpenAIRE

Avila, Martin; Carpenter, John; Mazé, Ramia

2010-01-01

‘3Ecologies’ makes visible factors affecting the sustainability of consumer products. Within engineering and economics, there are a variety of models for analyzing and ‘predicting’ the environmental factors such as energy, emissions and waste involved during production, consumption and disposal. We develop an expanded model, which emphasizes human impact and choices as well as potential consequences and futures. Psychological, sociological and environmental factors are mapped over time – thro...

Meta-analysis of greenhouse gas displacement factors of wood product substitution

International Nuclear Information System (INIS)

Sathre, Roger; O'Connor, Jennifer

2010-01-01

A displacement factor can express the efficiency of using biomass to reduce net greenhouse gas (GHG) emission, by quantifying the amount of emission reduction achieved per unit of wood use. Here we integrate data from 21 different international studies in a meta-analysis of the displacement factors of wood products substituted in place of non-wood materials. We calculate the displacement factors in consistent units of tons of carbon (tC) of emission reduction per tC in wood product. The displacement factors range from a low of -2.3 to a high of 15, with most lying in the range of 1.0 to 3.0. The average displacement factor value is 2.1, meaning that for each tC in wood products substituted in place of non-wood products, there occurs an average GHG emission reduction of approximately 2.1 tC. Expressed in other units, this value corresponds to roughly 3.9 t CO 2 eq emission reduction per ton of dry wood used. The few cases of negative displacement factors are the result of worst-case scenarios that are unrealistic in current practice. This meta-analysis quantifies the range of GHG benefits of wood substitution, and provides a clear climate rationale for increasing wood substitution in place of other products, provided that forests are sustainably managed and that wood residues are used responsibly.

Meta-analysis of greenhouse gas displacement factors of wood product substitution

Energy Technology Data Exchange (ETDEWEB)

Sathre, Roger [Ecotechnology, Mid Sweden University, 83125 Ostersund (Sweden); O' Connor, Jennifer [FPInnovations-Forintek, Vancouver, BC, Canada V6T 1W5 (Canada)

2010-04-15

A displacement factor can express the efficiency of using biomass to reduce net greenhouse gas (GHG) emission, by quantifying the amount of emission reduction achieved per unit of wood use. Here we integrate data from 21 different international studies in a meta-analysis of the displacement factors of wood products substituted in place of non-wood materials. We calculate the displacement factors in consistent units of tons of carbon (tC) of emission reduction per tC in wood product. The displacement factors range from a low of -2.3 to a high of 15, with most lying in the range of 1.0 to 3.0. The average displacement factor value is 2.1, meaning that for each tC in wood products substituted in place of non-wood products, there occurs an average GHG emission reduction of approximately 2.1 tC. Expressed in other units, this value corresponds to roughly 3.9 t CO{sub 2} eq emission reduction per ton of dry wood used. The few cases of negative displacement factors are the result of worst-case scenarios that are unrealistic in current practice. This meta-analysis quantifies the range of GHG benefits of wood substitution, and provides a clear climate rationale for increasing wood substitution in place of other products, provided that forests are sustainably managed and that wood residues are used responsibly.

Exploring driving factors of energy-related CO2 emissions in Chinese provinces: A case of Liaoning

International Nuclear Information System (INIS)

Geng, Yong; Zhao, Hongyan; Liu, Zhu; Xue, Bing; Fujita, Tsuyoshi; Xi, Fengming

2013-01-01

In order to uncover driving forces for provincial CO 2 emission in China, a case study was undertaken to shed light on the CO 2 emission growth in such a region. Liaoning province was selected due to its typical features as one industrial province. The environmental input–output analysis and structure decomposing analysis have been conducted in order to provide a holistic picture on Liaoning's CO 2 emissions during 1997–2007. Research outcomes indicate that rapid increase of per capita consumption activities is the main driver for Liaoning to have a significant CO 2 emission growth, followed by consumption structure, production structure and population size. Energy intensity and energy structure partly offset the CO 2 emission increase. Electricity power and heat supply and construction sectors caused the most CO 2 emission, indicating that more specific mitigation policies for these two sectors should be prepared. From final demand point of view, it is clear that trade plays a leading role in regional CO 2 emission, followed by fixed capital investment and urban household consumption which become increasingly important over time. Consequently, in order to realize low carbon development, local governments should consider all these factors so that appropriate mitigation policies can be raised by considering the local realities. - Highlights: • Driving forces for Liaoning's CO 2 emission have been uncovered through the use of IO-SDA model. • Construction and electricity power/heat supply sectors have the highest embodied emissions. • Trade plays a key role on regional CO 2 emission in Chinese old industrial base. • Fixed capital investment and urban households generated more CO 2 emissions

Emission factors and thermal efficiencies of cooking biofuels from five countries

International Nuclear Information System (INIS)

Gupta, S.; Saksena, S.; Shankar, V.R.; Joshi, V.

1998-01-01

The aim of the study was to compare the environmental and thermal performance of cooking biofuels from five countries. The standard water boiling test was used to determine thermal parameters. The fuels were burnt in a metal stove in a test chamber in accordance with standard protocol. Low-flow air samplers were used for particulate matter measurements, both TSP and RSP. Later, benzo(a)pyrene was determined using the high performance liquid chromatography (HPLC) technique after extraction from particulate samples in benzene. CO was measured using an electronic datalogger and HCHO using a passive sampler. The ventilation conditions during the experiments were manipulated by using different combinations of doors, windows and fans to ensure minimum stratification of pollutants in the chamber. The indirect method of deriving emission factors was used. Levels of most of the pollutants measured was found to be higher than that reported by previous studies, especially that of benzo(a)pyrene. (author)

Effect of Non-Stationary Combustion Phases on Emission Factors of Selected Pollutants and PCDD/F from Domestic Combustion

Czech Academy of Sciences Publication Activity Database

Šyc, Michal; Horák, J.; Krpec, K.; Hopan, F.; Ocelka, T.; Stáňa, M.

LVI, č. 2 (2010), s. 183-187 ISSN 1210-0471 R&D Projects: GA MŽP(CZ) SP/1A2/116/07; GA MŠk 2B08048 Institutional research plan: CEZ:AV0Z40720504 Keywords : combustion * emission factors * pollutants Subject RIV: CI - Industrial Chemistry, Chemical Engineering http://transactions.fs.vsb.cz/2010-2/1798.pdf

PARTICULATE MATTER CONCENTRATION AND EMISSION FACTOR IN THREE DIFFERENT LAYING HEN HOUSING SYSTEMS

Directory of Open Access Journals (Sweden)

Annamaria Costa

2009-09-01

Full Text Available The aim of this study was to evaluate PM10 concentration in three different laying hens houses (traditional battery cages with aerated open manure storage, aviary system and vertical tiered cages with manure belts with forced air drying and to evaluate particulate matter emission into atmosphere during one year of observation. Internal and external temperature and relative humidity, ventilation rate, PM10 concentration have been continuously monitored in order to evaluate particulate matter concentration changes during the day and the season and to define PM10 emission factors. PM10 concentration was corrected by gravimetric technique to lower measurements error. In the aviary system house, TSP and fine particulate matter (particles smaller than 2.5 micron concentration was measured. Average yearly PM10 concentration was remarkably higher in the aviary system house with 0.215 mg m-3 vs 108 mg m-3 for the ventilated belt house and vs 0.094 mg m-3 for the traditional battery cages house. In the Aviary system housing, TSP concentration was 0.444 mg m-3 and PM2.5 was 0.032 mg m-3, highlighting the existence of a severe working environment for men and animals. Recorded values for PM10 emission were 0.433 mg h-1 hen-1 for battery cages housing type, 0.081 mg h-1 hen-1 for ventilated belt cages house, values lower than those available in literature, while the aviary system housing type showed the highest PM10 emission (1.230 mg h-1 hen-1 with appreciable peaks during the morning, together with the increased animal activity and daily farmer operations, as feed administration, cleaning and droppings removal.

Allometric biomass and carbon factors database

Energy Technology Data Exchange (ETDEWEB)

Somogyi, Z. [European Commission Joint Research Centre, Ispra (Italy). Institute for Environment and Sustainability]|[Hungarian Forest Research Institute, Budapest (Hungary); Teobaldelli, M.; Federici, S.; Pagliari, V.; Grassi, G.; Seufert, G. [European Commission Joint Research Centre, Ispra (Italy). Institute for Environment and Sustainability; Matteucci, G. [Consiglio Nazionale delle Ricerche, Rende (Italy). Istituto per i Sistemi Agricoli e Forestali del Mediterraneo

2008-09-30

The United Nations Framework Convention on Climate Change (UNFCCC) and its Kyoto Protocol (KP) recognize that forest ecosystems may contribute to mitigate the human-induced greenhouse effect. In particular, Article 3.3 of the KP makes mandatory for countries that have ratified the KP to submit inventory information on the carbon stock changes and non-CO{sub 2} (carbon dioxide) emission from afforestation (A), reforestation (R) and deforestation (D), whereas Article 3.4 of the KP allows countries to elect specific activities, among others forest management (FM), whose emissions and removals must also be included in the greenhouse gas inventories. The greenhouse gas (GHG) inventory information, which Annex I (i.e., developed) countries have to submit to the UNFCCC secretariat annually, provides the basis for climate change policy analysis development, and for checking the compliance with Countries' commitments under the KP. As a Party to both the UNFCCC and its KP, the European Community (EC) has to submit its annual GHG inventory. Within the EC GHG inventory system, the Climate Change Unit of the Joint Research Centre (European Commission, DG-JRC) is responsible for the Quality Assessment/Quality Control of GHG emissions and sinks in the sectors 'Agriculture' and 'Land Use, Land Use Change and Forestry' (LULUCF), which includes the check of Member States' inventories and the contribution to the EC Inventory Report. The work of JRC on the EC inventory is complemented by continuous efforts for harmonizing and improving the measuring and reporting of GHG emissions and sinks in the agriculture and forestry sector in Europe. To this aim, the JRC has established a web site 'AFOLU DATA' with the aim to offer EU-wide data sets, models and other tools to promote transparent, complete, consistent and comparable estimates of GHG emissions and removals. The aim of the present paper is to illustrate one of the databases hosted by AFOLU

Decomposition of CO2 Emission Factors in Baoding

Science.gov (United States)

Li, Wei; Wang, xuyang; Zhang, Hongzhi

2018-01-01

Baoding, as one of the first “five provinces and eight cities” low carbon pilot cities, undertakes an important task and mission. The urgent task is to explore a peak route and emission reduction path suitable for Baoding’s own development, so as to provide reference for the construction of low-carbon pilot cities. At present, the carbon emissions of Baoding city and its subordinate districts and counties are not clear, and the carbon emissions, change trends and emission characteristics of various industries have not been systematically studied. This lead researcherscan not carry out further attribution analysis, the prediction of future emissions trends and put forward specific measures to reduce emissions are impossible.If the government can not accurately and comprehensively understand the problems faced in the construction and development of low-carbon cities, it is difficult to fundamentally put forward effective emission reduction policies and measures.

Characterization factors for thermal pollution in freshwater aquatic environments.

Science.gov (United States)

Verones, Francesca; Hanafiah, Marlia Mohd; Pfister, Stephan; Huijbregts, Mark A J; Pelletier, Gregory J; Koehler, Annette

2010-12-15

To date the impact of thermal emissions has not been addressed in life cycle assessment despite the narrow thermal tolerance of most aquatic species. A method to derive characterization factors for the impact of cooling water discharges on aquatic ecosystems was developed which uses space and time explicit integration of fate and effects of water temperature changes. The fate factor is calculated with a 1-dimensional steady-state model and reflects the residence time of heat emissions in the river. The effect factor specifies the loss of species diversity per unit of temperature increase and is based on a species sensitivity distribution of temperature tolerance intervals for various aquatic species. As an example, time explicit characterization factors were calculated for the cooling water discharge of a nuclear power plant in Switzerland, quantifying the impact on aquatic ecosystems of the rivers Aare and Rhine. The relative importance of the impact of these cooling water discharges was compared with other impacts in life cycle assessment. We found that thermal emissions are relevant for aquatic ecosystems compared to other stressors, such as chemicals and nutrients. For the case of nuclear electricity investigated, thermal emissions contribute between 3% and over 90% to Ecosystem Quality damage.

Emission factors of modern wood-pellet heating units under typical heating conditions - Final report; Emissionsfaktoren moderner Pelletkessel unter typischen Heizbedingungen - Schlussbericht

Energy Technology Data Exchange (ETDEWEB)

Good, J.; Nussbaumer, T.

2009-12-15

This final report for the Swiss Federal Office of Energy (SFOE) reports on the results of measurements made concerning the emission factors of two modern wood-pellet heating units under typical heating conditions. Using simulations, typical operation in single-family homes and apartment blocks were examined. Emissions during the different phases of operation were examined. Systems with and without buffer storage were also examined. The minimum running times to be striven for are quoted which would lead to a reduction of emissions to an acceptable level. The characteristic operating modes for the two heating units and the results obtained for various emissions are presented and discussed.

Ammonia emission factors from broiler litter in barns, in storage, and after land application.

Science.gov (United States)

Moore, Philip A; Miles, Dana; Burns, Robert; Pote, Dan; Berg, Kess; Choi, In Hag

2011-01-01

We measured NH₃ emissions from litter in broiler houses, during storage, and after land application and conducted a mass balance of N in poultry houses. Four state-of-the-art tunnel-ventilated broiler houses in northwest Arkansas were equipped with NH₃ sensors, anemometers, and data loggers to continuously record NH₃ concentrations and ventilation for 1 yr. Gaseous fluxes of NH₃, N₂O, CH₄, and CO₂ from litter were measured. Nitrogen (N) inputs and outputs were quantified. Ammonia emissions during storage and after land application were measured. Ammonia emissions during the flock averaged approximately 15.2 kg per day-house (equivalent to 28.3 g NH₃per bird marketed). Emissions between flocks equaled 9.09 g NH₃ per bird. Hence, in-house NH₃ emissions were 37.5 g NH₃ per bird, or 14.5 g kg(-1) bird marketed (50-d-old birds). The mass balance study showed N inputs for the year to the four houses totaled 71,340 kg N, with inputs from bedding, chicks, and feed equal to 303, 602, and 70,435 kg, respectively (equivalent to 0.60, 1.19, and 139.56 g N per bird). Nitrogen outputs totaled 70,396 kg N. Annual N output from birds marketed, NH₃ emissions, litter or cake, mortality, and NO₂ emissions was 39,485, 15,571, 14,464, 635, and 241 kg N, respectively (equivalent to 78.2, 30.8, 28.7, 1.3, and 0.5 g N per bird). The percent N recovery for the N mass balance study was 98.8%. Ammonia emissions from stacked litter during a 16-d storage period were 172 g Mg(-1) litter, which is equivalent to 0.18 g NH₃ per bird. Ammonia losses from poultry litter broadcast to pastures were 34 kg N ha (equivalent to 15% of total N applied or 7.91 g NH₃ per bird). When the litter was incorporated into the pasture using a new knifing technique, NH₃ losses were virtually zero. The total NH₃ emission factor for broilers measured in this study, which includes losses in-house, during storage, and after land application, was 45.6 g NH₃ per bird marketed. by the

Measurements of VOC/SVOC emission factors from burning incenses in an environmental test chamber: influence of temperature, relative humidity, and air exchange rate.

Science.gov (United States)

Manoukian, A; Buiron, D; Temime-Roussel, B; Wortham, H; Quivet, E

2016-04-01

This study investigates the influence of three environmental indoor parameters (i.e., temperature, relative humidity, and air exchange rate) on the emission of 13 volatile organic compounds (VOCs) and semi-volatile organic compounds (SVOCs) during incense burning. Experiments have been carried out using an environmental test chamber. Statistical results from a classical two-level full factorial design highlight the predominant effect of ventilation on emission factors. The higher the ventilation, the higher the emission factor. Moreover, thanks to these results, an estimation of the concentration range for the compounds under study can be calculated and allows a quick look of indoor pollution induced by incense combustion. Carcinogenic substances (i.e., benzene, benzo(a)pyrene, and formaldehyde) produced from the incense combustion would be predicted in typical living indoors conditions to reach instantaneous concentration levels close to or higher than air quality exposure threshold values.

Works made by the working group on the division by four by 2050 of France's greenhouse gas emissions, named 'factor 4'. January 19, 2006 meeting

International Nuclear Information System (INIS)

2006-01-01

A working group was created on September 8, 2005 by the French minister of ecology and sustainable development and the French minister of industry with the aim of exploring all possible paths allowing to reach the long term goal of dividing by a factor 4 the French greenhouse gas emissions from now to 2050. This paper gathers the transparencies of three presentations given at the January 19, 2006 meeting of the 'Factor 4' working group: behaviour of energy consumers; which public policies to reach the factor 4; macro-economics of the factor 4. (J.S.)

Success Factors for Clean Development Mechanism Implementation in Malaysia

Directory of Open Access Journals (Sweden)

Say Keat Ooi

2013-09-01

Full Text Available The Clean Development Mechanism (CDM, established under the Kyoto Protocol, is one of the market-based mechanisms developed to assist industrialized countries mitigate greenhouse gas (GHG emissions, achieve emission reduction targets, and at the same time promote sustainable development in developing countries. The CDM, which provides flexibility and costeffectiveness in meeting GHG emission reduction targets, has captured interest globally. CDM implementation is expected to generate benefits, give developing countries a sense of ownership, and share the global load in tackling global warming and climate change. However, CDM implementation faces several complications. The successful participation of developing countries in emission reduction projects presents ongoing challenges, which inhibit their drive towards sustainable development goals. Through a comprehensive review of the literature and theoretical analysis, several factors have been identified as significant to successful CDM implementation in Malaysia. These success factors, which include regulation and a legal framework, competitive advantage, green supply chain, ethical values, financial benefits, and technology transfer, are presented and the importance of each factor is discussed.

How best management practices affect emissions in gas turbine power plants - an important factor to consider when strengthening emission standards.

Science.gov (United States)

Zeng, Jinghai; Xing, Min; Hou, Min; England, Glenn C; Yan, Jing

2018-04-27

The Beijing Municipal Environmental Protection Bureau (EPB) is considering strengthening the Emission Standard of Air Pollutants for Stationary Gas Turbines, originally published in 2011 (DB11/847-2011), with a focus on reducing nitrogen oxides (NOx) emissions. A feasibility study was conducted to evaluate the current operation of twelve (12) existing combined-cycle gas turbine power plants and the design of two (2) new plants in Beijing and their emission reduction potential, in comparison with a state-of-the-art power plant in California, United States. The study found that Best Management Practices (BMPs) could potentially improve the emission level of the power plants, and should be implemented to minimize emissions under current design characteristics. These BMPs include (1) more frequent tuning of turbine combustors; (2) onsite testing of natural gas characteristics in comparison to turbine manufacturer's specifics and tuning of turbine to natural gas quality; (3) onsite testing of aqueous ammonia to ensure adequate ammonia concentration in the mixed solution, and the purity of the solution; (4) more careful inspection of the heat recovery steam generator (HRSG), and the selective catalytic reduction (SCR) during operation and maintenance; (5) annual testing of the catalyst coupon on the SCR to ensure catalyst effectiveness; and (6) annual ammonia injection grid (AIG) tuning. The study found that without major modification to the plants, improving the management of the Beijing gas turbine power plants may potentially reduce the current hourly-average NOx emission level of 5-10 parts per million (ppm, ranges reflects plant variation) by up to 20%. The exact improvement associated with each BMP for each facility requires more detailed analysis, and requires engagement of turbine, HRSG, and SCR manufacturers. This potential improvement is an important factor to consider when strengthening the emission standard. However it is to be noted that with the continuous

How organizational and global factors condition the effects of energy efficiency on CO_2 emission rebounds among the world's power plants

International Nuclear Information System (INIS)

Grant, Don; Jorgenson, Andrew K.; Longhofer, Wesley

2016-01-01

The United Nations Intergovernmental Panel on Climate Change (IPCC), the International Energy Agency (IEA), and several nations suggest that energy efficiency is an effective strategy for reducing energy consumption and associated greenhouse gas emissions. Skeptics contend that because efficiency lowers the price of energy and energy services, it may actually increase demand for them, causing total emissions to rise. While both sides of this debate have researched the magnitude of these so-called rebound effects among end-use consumers, researchers have paid less attention to the conditions under which direct rebounds cause CO_2 emissions to rise among industrial producers. In particular, researchers have yet to explore how organizational and global factors might condition the effects of efficiency on emissions among power plants, the world's most concentrated sources of anthropogenic greenhouse gases. Here we use a unique dataset containing nearly every fossil-fuel power plant in the world to determine whether the impact of efficiency on emissions varies by plants' age, size, and location in global economic and normative systems. Findings reveal that each of these factors has a significant interaction with efficiency and thus shapes environmentally destructive rebound effects. - Highlights: •Skeptics charge that energy efficiency may actually cause CO_2 emissions to rise. •Few have examined whether such rebound effects occur among power plants. •Little also known about whether plants' organizational and global characteristics condition rebounds. •Conduct first analysis of rebound effects among the world's power plants. •Rebounds found to depend on plants' age, size, and location in international economic and normative systems.

Study on Influencing Factors of Carbon Emissions from Energy Consumption of Shandong Province of China from 1995 to 2012

Science.gov (United States)

Song, Jiekun; Song, Qing; Zhang, Dong; Lu, Youyou; Luan, Long

2014-01-01

Carbon emissions from energy consumption of Shandong province from 1995 to 2012 are calculated. Three zero-residual decomposition models (LMDI, MRCI and Shapley value models) are introduced for decomposing carbon emissions. Based on the results, Kendall coordination coefficient method is employed for testing their compatibility, and an optimal weighted combination decomposition model is constructed for improving the objectivity of decomposition. STIRPAT model is applied to evaluate the impact of each factor on carbon emissions. The results show that, using 1995 as the base year, the cumulative effects of population, per capita GDP, energy consumption intensity, and energy consumption structure of Shandong province in 2012 are positive, while the cumulative effect of industrial structure is negative. Per capita GDP is the largest driver of the increasing carbon emissions and has a great impact on carbon emissions; energy consumption intensity is a weak driver and has certain impact on carbon emissions; population plays a weak driving role, but it has the most significant impact on carbon emissions; energy consumption structure is a weak driver of the increasing carbon emissions and has a weak impact on carbon emissions; industrial structure has played a weak inhibitory role, and its impact on carbon emissions is great. PMID:24977216

Study on Influencing Factors of Carbon Emissions from Energy Consumption of Shandong Province of China from 1995 to 2012

Directory of Open Access Journals (Sweden)

Jiekun Song

2014-01-01

Full Text Available Carbon emissions from energy consumption of Shandong province from 1995 to 2012 are calculated. Three zero-residual decomposition models (LMDI, MRCI and Shapley value models are introduced for decomposing carbon emissions. Based on the results, Kendall coordination coefficient method is employed for testing their compatibility, and an optimal weighted combination decomposition model is constructed for improving the objectivity of decomposition. STIRPAT model is applied to evaluate the impact of each factor on carbon emissions. The results show that, using 1995 as the base year, the cumulative effects of population, per capita GDP, energy consumption intensity, and energy consumption structure of Shandong province in 2012 are positive, while the cumulative effect of industrial structure is negative. Per capita GDP is the largest driver of the increasing carbon emissions and has a great impact on carbon emissions; energy consumption intensity is a weak driver and has certain impact on carbon emissions; population plays a weak driving role, but it has the most significant impact on carbon emissions; energy consumption structure is a weak driver of the increasing carbon emissions and has a weak impact on carbon emissions; industrial structure has played a weak inhibitory role, and its impact on carbon emissions is great.

Metal toxicity characterization factors for marine ecosystems: considering the importance of the estuary for freshwater emissions

DEFF Research Database (Denmark)

Dong, Yan; Rosenbaum, Ralph K.; Hauschild, Michael Zwicky

2017-01-01

The study develops site-dependent characterization factors (CFs) for marine ecotoxicity of metals emitted to freshwater, taking their passage of the estuary into account. To serve life cycle assessment (LCA) studies where emission location is often unknown, site-generic marine CFs were developed...... with an estuary removal process to calculate FF. BF and EF were taken from Dong et al. Environ Sci Technol 50:269–278 (2016). Site-generic marine CFs were derived from site-dependent marine CFs. Different averaging principles were tested, and the approach representing estuary discharge rate was identified...... between both methods. Accounting for estuary removal particularly influences marine ecotoxicity CFs for emission to freshwater of metals that have a strong tendency to complex-bind to particles. It indicates the importance of including estuary in the characterization modelling when dealing with those...

Aerosol emissions factors from traditional biomass cookstoves in India: insights from field measurements

Directory of Open Access Journals (Sweden)

A. Pandey

2017-11-01

Full Text Available Residential solid biomass cookstoves are important sources of aerosol emissions in India. Cookstove emissions rates are largely based on laboratory experiments conducted using the standard water-boiling test, but real-world emissions are often higher owing to different stove designs, fuels, and cooking methods. Constraining mass emissions factors (EFs for prevalent cookstoves is important because they serve as inputs to bottom-up emissions inventories used to evaluate health and climate impacts. Real-world EFs were measured during winter 2015 for a traditional cookstove (chulha burning fuel wood, agricultural residue, and dung from different regions of India. Average (±95 % confidence interval EFs for fuel wood, agricultural residue, and dung were (1 PM2.5 mass: 10.5 (7.7–13.4 g kg−1, 11.1 (7.7–15.5 g kg−1, and 22.6 (14.9–32.9 g kg−1, respectively; (2 elemental carbon (EC: 0.9 (0.6–1.4 g kg−1, 1.6 (0.6–3.0 g kg−1, and 1.0 (0.4–2.0 g kg−1, respectively; and (3 organic carbon (OC: 4.9 (3.2–7.1 g kg−1, 7.0 (3.5–12.5 g kg−1, and 12.9 (4.2–15.01 g kg−1, respectively. The mean (±95 % confidence interval OC ∕ EC mass ratios were 6.5 (4.5–9.1, 7.6 (4.4–12.2, and 12.7 (6.5–23.3, respectively, with OC and EC quantified by the IMPROVE_A thermal-optical reflectance protocol. These real-world EFs are higher than those from previous laboratory-based measurements. Combustion conditions have larger effects on EFs than the fuel types. We also report the carbon mass fractions of our aerosol samples determined using the thermal-optical reflectance method. The mass fraction profiles are consistent between the three fuel categories but markedly different from those reported in past literature – including the source profiles for wood stove PM2.5 emissions developed as inputs to receptor modeling studies conducted by the Central Pollution Control Board of India. Thermally

Greybody factors for d-dimensional black holes

DEFF Research Database (Denmark)

Harmark, Troels; Natário, José; Schiappa, Ricardo

2010-01-01

Gravitational greybody factors are analytically computed for static, spherically symmetric black holes in d-dimensions, including black holes with charge and in the presence of a cosmological constant (where a proper definition of greybody factors for both asymptotically de Sitter and anti...... of the details of the black hole. For asymptotically de Sitter black holes the greybody factor is different for even or odd spacetime dimension, and proportional to the ratio of the areas of the event and cosmological horizons. For asymptotically Ads black holes the greybody factor has a rich structure in which...... universality is hidden in the transmission and reflection coefficients. For either charged or asymptotically de Sitter black holes the greybody factors are given by non-trivial functions, while for asymptotically Ads black holes the greybody factor precisely equals one (corresponding to pure blackbody emission)....

Clearinghouse for Inventories and Emissions Factors

Science.gov (United States)

Emissions inventories, modeling, and monitoring are the basis for understanding, controlling and tracking stationary sources of air pollution. This technical site provides access to tools and data to support those efforts.

Wildland fire emissions, carbon, and climate: Emission factors

Science.gov (United States)

Shawn Urbanski

2014-01-01

While the vast majority of carbon emitted by wildland fires is released as CO2, CO, and CH4, wildland fire smoke is nonetheless a rich and complex mixture of gases and aerosols. Primary emissions include significant amounts of CH4 and aerosol (organic aerosol and black carbon), which are short-lived climate forcers. In addition to CO2 and short-lived climate forcers,...

49 CFR 325.73 - Microphone distance correction factors. 1

Science.gov (United States)

2010-10-01

... 49 Transportation 5 2010-10-01 2010-10-01 false Microphone distance correction factors. 1 325.73 Section 325.73 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL MOTOR... MOTOR CARRIER NOISE EMISSION STANDARDS Correction Factors § 325.73 Microphone distance correction...

Effects of Inhalation of Emissions from Cedar Timber on Psychological and Physiological Factors in an Indoor Environment

Directory of Open Access Journals (Sweden)

Kenichi Azuma

2016-12-01

Full Text Available Components extracted from cedar timber have been reported to have stress-reducing effects in humans. If the positive effects of cedar timber in indoor environments are scientifically proven, an indoor environment that utilizes cedar timber may contribute to the improvement or promotion of well-being in humans. In this study, we evaluated the effects of inhaling emissions of volatile constituents from cedar timber (Cryptomeria japonica on the psychological and physiological factors in indoor environments. A case-control study with a crossover design was conducted with 10 subjects occupying two rooms that were controlled for interior materials, indoor climate, and room size. Cedrol and β-eudesmol were specifically detected in the case room. However, no significant differences were observed in psychological and physiological factors. There was a significant loss in vigor in the control group from the time before entering the room to the time after leaving the room; however, this loss in vigor was not seen in the case group. Temperature conditions were higher than the indoor environmental standard in Japan but similar in the two groups. Our results showed a minor positive change in vigor among participants exposed to cedar timber for a short term. Inhalation of emissions of volatile constituents from cedar timber may have positive effects in humans; however, further research on their efficacy is needed.

An equivalence factor between CO2 avoided emissions and sequestration. Description and applications in forestry

International Nuclear Information System (INIS)

Costa, P.M.; Wilson, C.

2000-01-01

Concern about the issue of permanence and reversibility of the effects of carbon sequestration has led to the need to devise accounting methods that quantify the temporal value of storing carbon that has been actively sequestered or removed from the atmosphere, as compared to carbon stored as a result of activities taken to avoid emissions. This paper describes a method for accounting for the atmospheric effects of sequestration-based land-use projects in relation to the duration of carbon storage. Firstly, the time period over which sequestered carbon should be stored in order to counteract the radiative forcing effect of carbon emissions was calculated, based on the residence time and decay pattern of atmospheric CO2, its Absolute Global Warming Potential. This time period was called the equivalence time, and was calculated to be approximately 55 years. From this equivalence time, the effect of storage of 1 t CO2 for 1 year was derived, and found to be similar to preventing the effect of the emission of 0.0182 t CO2. Potential applications of this tonne.year figure, here called the equivalence factor, are then discussed in relation to the estimation of atmospheric benefits over time of sequestration-based land use projects. 15 refs

Emission of hydrogen sulfide (H2S) at a waterfall in a sewer: study of main factors affecting H2S emission and modeling approaches.

Science.gov (United States)

Jung, Daniel; Hatrait, Laetitia; Gouello, Julien; Ponthieux, Arnaud; Parez, Vincent; Renner, Christophe

2017-11-01

Hydrogen sulfide (H 2 S) represents one of the main odorant gases emitted from sewer networks. A mathematical model can be a fast and low-cost tool for estimating its emission. This study investigates two approaches to modeling H 2 S gas transfer at a waterfall in a discharge manhole. The first approach is based on an adaptation of oxygen models for H 2 S emission at a waterfall and the second consists of a new model. An experimental set-up and a statistical data analysis allowed the main factors affecting H 2 S emission to be studied. A new model of the emission kinetics was developed using linear regression and taking into account H 2 S liquid concentration, waterfall height and fluid velocity at the outlet pipe of a rising main. Its prediction interval was estimated by the residual standard deviation (15.6%) up to a rate of 2.3 g H 2 S·h -1 . Finally, data coming from four sampling campaigns on sewer networks were used to perform simulations and compare predictions of all developed models.

Monte Carlo calculation of correction factors for radionuclide neutron source emission rate measurement by manganese bath method

International Nuclear Information System (INIS)

Li Chunjuan; Liu Yi'na; Zhang Weihua; Wang Zhiqiang

2014-01-01

The manganese bath method for measuring the neutron emission rate of radionuclide sources requires corrections to be made for emitted neutrons which are not captured by manganese nuclei. The Monte Carlo particle transport code MCNP was used to simulate the manganese bath system of the standards for the measurement of neutron source intensity. The correction factors were calculated and the reliability of the model was demonstrated through the key comparison for the radionuclide neutron source emission rate measurements organized by BIPM. The uncertainties in the calculated values were evaluated by considering the sensitivities to the solution density, the density of the radioactive material, the positioning of the source, the radius of the bath, and the interaction cross-sections. A new method for the evaluation of the uncertainties in Monte Carlo calculation was given. (authors)

Activation of 125I-Factor IX and 125I-Factor X: Effect of tissue factor and Factor VII, Factor Xsub(a) and thrombin

International Nuclear Information System (INIS)

Oesterud, B.; Rapaport, S.I.

Activation of Factor IX and Factor X was studied by adding 125 I-Factor IX or 125 I-Factor X to reaction mixtures and quantitating cleavage products by reduced sodium dodecylsulfate gel electrophoresis. Thrombin failed to activate Factors IX or X; Factor Xsub(a) produced insignificant amounts of cleavage products of both factors. In contrast, the reaction product of tissue factor and Factor VII cleaved large amounts of both Factor IX and Factor X in purified systems and in plasma. In incubation mixtures of plasma containing added 125 I-Factor IX or 125 I-Factor X, tissue factor and Ca 2+ ions, the percentage of total radioactivity in the heavy chain peak of 125 I-IXsub(a) and the heavy chain of 125 I-Xsub(a) increased at a similar rate. When the tissue factor was diluted, similar curves were obtained for percent cleavage of 125 I-Factor IX and percent cleavage of 125 I-Factor X plotted against tissue factor concentration. These findings support the hypothesis that activation of Factor IX by the tissue factor-Factor VII reaction product represents a physiologically significant step in normal haemostasis. (author)

Mobility as a territorial key factor in the emission of greenhouse gases; La movilidad como factor territorial dominante en la emision de gases de efecto invernadero

Energy Technology Data Exchange (ETDEWEB)

Crespo Garcia, L.; Montane Lopez, M. M.; Garcia Cortes, A.; Jimenez Arroyo, F.

2011-07-01

Transport and energy generation are the two dominant sectors in the overall balance of energy consumption, and thus of greenhouse gases emissions. Placement of energy generation plants responds to strategic reasons relate to energy supply in the Spanish territory, while transport is an economic activity tightly related to the productive structure and territorial characteristics: density of populations, geographic situation, efficient space organization, etc. The analysis of these factors enables to prioritize different strategies according the their energetic efficiency in order to pursue an economy less dependent of fossil fuels, focused in activities of higher added value and that keeps in mind limits and strengths of Spanish reality. (Author) 9 refs.

Environmental data book 2011. Estimated emission factors for fuels, electricity, heat and transport in Sweden; Miljoefaktaboken 2011. Uppskattade emissionsfaktorer foer braenslen, el, vaerme och transporter

Energy Technology Data Exchange (ETDEWEB)

Gode, Jenny; Martinsson, Fredrik; Hagberg, Linus; Oeman, Andreas; Hoeglund, Jonas; Palm, David

2011-04-15

The environmental data book summarizes current and general emission factors for most fuels and sources of Swedish electricity and heat and to power vehicles. Emission data are compiled for wood fuels, energy crops, bio-oils, waste fuels, fossil fuels and peat, biofuels, wind power, hydro power, nuclear power and solar power

Emission of Methane From Enteric Fermentation: National Contribution and Factors Affecting it in Livestock

Directory of Open Access Journals (Sweden)

Budi Haryanto

2009-12-01

Full Text Available Changing in atmosphere condition is affected by the quantity of gases produced from all activities on the earth. Gases that have effects on global warming are CO2, N2O, H2O, and CH4 (methane. Among other sources of methane are enteric fermentation of organic material from ruminants and feces decomposition. Methane production from ruminants is affected by several factors such as breed/type of animal, feed quality, environmental temperature and physiological status of the animal. Energy as methane in ruminants may reach 2 to 15% of the total energy consumption. To reduce the emission of methane from ruminants, it is necessary to apply a strategic feeding system for more efficient utilization of feed.

Modeling state-level soil carbon emission factors under various scenarios for direct land use change associated with United States biofuel feedstock production

International Nuclear Information System (INIS)

Kwon, Ho-Young; Mueller, Steffen; Dunn, Jennifer B.; Wander, Michelle M.

2013-01-01

Current estimates of life cycle greenhouse gas emissions of biofuels produced in the US can be improved by refining soil C emission factors (EF; C emissions per land area per year) for direct land use change associated with different biofuel feedstock scenarios. We developed a modeling framework to estimate these EFs at the state-level by utilizing remote sensing data, national statistics databases, and a surrogate model for CENTURY's soil organic C dynamics submodel (SCSOC). We estimated the forward change in soil C concentration within the 0–30 cm depth and computed the associated EFs for the 2011 to 2040 period for croplands, grasslands or pasture/hay, croplands/conservation reserve, and forests that were suited to produce any of four possible biofuel feedstock systems [corn (Zea Mays L)-corn, corn–corn with stover harvest, switchgrass (Panicum virgatum L), and miscanthus (Miscanthus × giganteus Greef et Deuter)]. Our results predict smaller losses or even modest gains in sequestration for corn based systems, particularly on existing croplands, than previous efforts and support assertions that production of perennial grasses will lead to negative emissions in most situations and that conversion of forest or established grasslands to biofuel production would likely produce net emissions. The proposed framework and use of the SCSOC provide transparency and relative simplicity that permit users to easily modify model inputs to inform biofuel feedstock production targets set forth by policy. -- Highlights: ► We model regionalized feedstock-specific United States soil C emission factors. ► We simulate soil C changes from direct land use change associated with biofuel feedstock production. ► Corn, corn-stover, and perennial grass biofuel feedstocks grown in croplands maintain soil C levels. ► Converting grasslands to bioenergy crops risks soil C loss. ► This modeling framework yields more refined soil C emissions than national-level emissions

Future Emissions from Railway Traffic

DEFF Research Database (Denmark)

Sorenson, Spencer C.

1998-01-01

In investigation of the expected development in factors which influence railway energy consumption and emissions. Traffic factors such as train speed, load, an occupancy were considered. Tehcnical factors such an emissions factors, fleet composition and train weight were also considered. An estim......In investigation of the expected development in factors which influence railway energy consumption and emissions. Traffic factors such as train speed, load, an occupancy were considered. Tehcnical factors such an emissions factors, fleet composition and train weight were also considered...

Procedure for measurement of anisotropy factor for neutron sources

International Nuclear Information System (INIS)

Creazolla, Prycylla Gomes

2017-01-01

Radioisotope neutron sources allow the production of reference fields for calibration of neutron detectors for radiation protection and analysis purposes. When the emission rate of these sources is isotropic, no correction is necessary. However, variations in source encapsulation and in the radioactive material concentration produce differences in its neutron emission rate, relative to the source axis, this effect is called anisotropy. In this study, is describe a procedure for measuring the anisotropy factor of neutron sources performed in the Laboratório de Metrologia de Neutrons (LN) using a Precision Long Counter (PLC) detector. A measurement procedure that takes into account the anisotropy factor of neutron sources contributes to solve some issues, particularly with respect to the high uncertainties associated with neutron dosimetry. Thus, a bibliographical review was carried out based on international standards and technical regulations specific to the area of neutron fields, and were later reproduced in practice by means of the procedure for measuring the anisotropy factor in neutron sources of the LN. The anisotropy factor is determined as a function of the angle of 90° in relation to the cylindrical axis of the source. This angle is more important due to its high use in measurements and also of its higher neutron emission rate if compared with other angles. (author)

PM4 crystalline silica emission factors and ambient concentrations at aggregate-producing sources in California.

Science.gov (United States)

Richards, John R; Brozell, Todd T; Rea, Charles; Boraston, Geoff; Hayden, John

2009-11-01

The California Construction and Industrial Minerals Association and the National Stone, Sand, & Gravel Association have sponsored tests at three sand and gravel plants in California to compile crystalline silica emission factors for particulate matter (PM) of aerodynamic diameter of 4 microm or less (PM4) and ambient concentration data. This information is needed by industrial facilities to evaluate compliance with the Chronic Reference Exposure Level (REL) for ambient crystalline silica adopted in 2005 by the California Office of Environmental Health Hazard Assessment. The REL applies to PM4 respirable PM. Air Control Techniques, P.C. sampled for PM4 crystalline silica using a conventional sampler for PM of aerodynamic diameter of 2.5 microm or less (PM2.5), which met the requirements of 40 Code of Federal Regulations Part 50, Appendix L. The sample flow rate was adjusted to modify the 50% cut size to 4 microm instead of 2.5 microm. The filter was also changed to allow for crystalline silica analyses using National Institute for Occupational Safety and Health (NIOSH) Method 7500. The particle size-capture efficiency curve for the modified Appendix L instrument closely matched the performance curve of NIOSH Method 0600 for PM4 crystalline silica and provided a minimum detection limit well below the levels attainable with NIOSH Method 0600. The results of the tests indicate that PM4 crystalline silica emissions range from 0.000006 to 0.000110 lb/t for screening operations, tertiary crushers, and conveyor transfer points. The PM4 crystalline silica emission factors were proportional to the crystalline silica content of the material handled in the process equipment. Measured ambient concentrations ranged from 0 (below detectable limit) to 2.8 microg/m3. All values measured above 2 microg/m3 were at locations upwind of the facilities being tested. The ambient PM4 crystalline silica concentrations measured during this study were below the California REL of 3 microg/m3

Factoring the car-climate challenge: Insights and implications

International Nuclear Information System (INIS)

DeCicco, John M.

2013-01-01

Three approaches commonly are identified for controlling automobile greenhouse gas (GHG) emissions: reducing travel demand, improving vehicle efficiency and using alternatively (non-petroleum) fueled vehicles (AFVs). Similarly, sector emissions are factored by travel distance, vehicle fuel intensity and fuel GHG (“carbon”) intensity. Analyzing these factors using US and China data reveals that for a broad range of conditions, stringent GHG emissions limits for the auto sector imply limits of comparable stringency for fuel carbon intensity. However, carbon intensity is a modeled representation of complex energy supply and use systems rather than a measurable property of fuels themselves. Carefully examining the locations and magnitudes of fuel-related emissions indicates that the proper policy focus is on the sectors that supply fuel rather than the choice of fuels in the auto sector. Therefore, beyond fundamental R and D, policies to commercialize AFVs are not necessarily required for climate protection at present. In addition to managing travel demand and improving vehicle efficiency, the implied policy priority is limiting net GHG impacts in the energy and other natural resource sectors that supply fuels. Future work is needed to develop GHG management protocols for liquid fuel supply systems involving fungible commodities and dynamic global supply chains. - Highlights: • Factor analysis offers insights about ways to reduce automotive GHG emissions. • Improving vehicle efficiency and reducing travel demand remain important. • Reducing net GHG impacts in energy sectors that supply motor fuels is also a priority. • Commercialization of alternatively fueled vehicles is not necessarily required at present

The spatial distribution of commuting CO2 emissions and the influential factors: A case study in Xi'an, China

Directory of Open Access Journals (Sweden)

Yuan-Yuan Liu

2015-03-01

Full Text Available As the transport sector is a major source of greenhouse gas emissions, the effect of urbanization on transport CO2 emissions in developing cities has become a key issue under global climate change. Examining the case of Xi'an, this paper aims to explore the spatial distribution of commuting CO2 emissions and influencing factors in the new, urban industry zones and city centers considering Xi'an's transition from a monocentric to a polycentric city in the process of urbanization. Based on household survey data from 1501 respondents, there are obvious differences in commuting CO2 emissions between new industry zones and city centers: City centers feature lower household emissions of 2.86 kg CO2 per week, whereas new industry zones generally have higher household emissions of 3.20 kg CO2 per week. Contrary to previous research results, not all new industry zones have high levels of CO2 emissions; with the rapid development of various types of industries, even a minimum level of household emissions of 2.53 kg CO2 per week is possible. The uneven distribution of commuting CO2 emissions is not uniformly affected by spatial parameters such as job–housing balance, residential density, employment density, and land use diversity. Optimum combination of the spatial parameters and travel pattern along with corresponding transport infrastructure construction may be an appropriate path to reduction and control of emissions from commuting.

Physical factors affecting single photon emission computed tomography (SPECT) applied in nuclear medicine

International Nuclear Information System (INIS)

Farag, H.I.; Khalil, W.A.; Hassan, R.A.

2003-01-01

many physical factors degrade single photon emission computed tomography (SPECT) images both qualitatively and quantitatively. Physical properties important for the assessment of the potential of emission computed tomography implemented by collimated detector systems include sensitivity, statistical and angular sampling requirements, attenuation compensation, resolution, uniformity, and multisection design constraints. SPECT has highlighted the used to improve gamma camera performance. Flood field nonuniformity is translated into tomographic the need to improve gamma camera performance. Flood field nonuniformity is translated into tomographic images as major artifacts because it distorts the data obtained at each projection. Also, poor energy resolution translates directly into degraded spatial resolution through reduced ability to reject scattered photons on the basic of pluses height analysis. The aim of this work is study the different and most important acquisition and processing parameters, which affect the quality of the SPECT images. The present study investigates the various parameters effecting SPECT images and experimental results demonstrate that: daily uniformity checks and evaluation are essential to ensure that the SPECT system is working properly. The Core used in the reconstruction process could be correct to avoid data misalignment. 60 mumblers of views gave the best image quality, rather than 20 or 30 views. Time per view (TPV) 30 or 20 sec gave a good image quality, rather than high-resolution collimator, is recommended in order to provide good spatial resolution. On the other hand patient motion could cause serious reconstruction artifacts. A cine display is recommended to identify movement artifacts. In the case of matrix size, matrix 128x128 give the best resolution than matrix 64x64. Energy window width, 15% compared with the standard 20% improved the resolution. Butter worth filter (cut off 0.57 cyc/cm with order 6 ) give the best resolution

Emission factors and congener-specific characterization of PCDD/Fs, PCBs, PBDD/Fs and PBDEs from an off-road diesel engine using waste cooking oil-based biodiesel blends.

Science.gov (United States)

Chen, Shui-Jen; Tsai, Jen-Hsiung; Chang-Chien, Guo-Ping; Huang, Kuo-Lin; Wang, Lin-Chi; Lin, Wen-Yinn; Lin, Chih-Chung; Yeh, C Kuei-Jyum

2017-10-05

Few studies have been performed up to now on the emission factors and congener profiles of persistent organic pollutants (POPs) emitted from off-road diesel engines. This investigation elucidates the emission factors and congener profiles of various POPs, namely polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyl (PCBs), polybrominated dibenzo-p-dioxins and polybrominated dibenzofurans (PBDD/Fs) and polybrominated diphenyl ethers (PBDEs), in the exhausts of a diesel generator fueled with different waste cooking oil-based biodiesel (WCO-based biodiesel) blends. The PCDD/Fs contributed 87.2% of total dioxin-like toxicity (PCDD/Fs+PCBs+PBDD/Fs) in the exhaust, while the PCBs and PBDD/Fs only contributed 8.2% and 4.6%, respectively. Compared with petroleum diesel, B20 (20vol% WCO-based biodiesel+80vol% diesel) reduced total toxicity by 46.5% for PCDD/Fs, 47.1% for PCBs, and 24.5% for PBDD/Fs, while B40 (40vol% WCO-based biodiesel+60vol% diesel) reduced it by 89.5% for PCDD/Fs, 57.1% for PCBs, and 63.2% for PBDD/Fs in POP emission factors. The use of WCO-based biodiesel not only solves the problem of waste oil disposal, but also lowers POP emissions from diesel generators. Copyright © 2017 Elsevier B.V. All rights reserved.

The enhanced nucleation factors and field electron emission property of diamond synthesized by RF-PECVD

Energy Technology Data Exchange (ETDEWEB)

Yang Guangmin [College of Physics, Changchun Normal University, Jilin Province, Changchun 130032 (China); Xu Qiang [Changchun Institute of Technology, Changchun 130021 (China); Wang Xin [Department of Materials Science, Key Laboratory of Mobile Materials, MOE, and State Key Laboratory of Superhard Materials, Jilin University, Changchun 130012 (China); Zheng Weitao, E-mail: wtzheng@jlu.edu.cn [Department of Materials Science, Key Laboratory of Mobile Materials, MOE, and State Key Laboratory of Superhard Materials, Jilin University, Changchun 130012 (China)

2012-03-15

Highlights: Black-Right-Pointing-Pointer Submicron-diamond, microcrystalline diamond, and nanocrystalline diamond were synthesized using different substrates and pretreatment methods. Black-Right-Pointing-Pointer Three techniques have been developed to create some density of diamond on substrate surfaces by PECVD deposition procedure. Black-Right-Pointing-Pointer The field electron emission property was also investigated. - Abstract: In this work, submicron-diamond (SD), microcrystalline diamond (MD), and nanocrystalline diamond (ND) were synthesized using different substrates and pretreatment methods. In order to investigate influencing factors on nucleation, three techniques have been developed to create some density of diamond on substrate surfaces: (a) with chemical-etching technique (NaOH water solution at 80 Degree-Sign C for 3, 8, 15 min, respectively), (b) (Co(NO{sub 3}){sub 3}/Mg(NO{sub 3}){sub 2}{center_dot}6H{sub 2}O or Fe(NO{sub 3}){sub 3}{center_dot}9H{sub 2}O/Mg(NO{sub 3}){sub 2}{center_dot}6H{sub 2}O alcohol solution) dripping on silicon substrate, and (c) NaCl substrate directly by following a same PECVD deposition procedure. Furthermore, the field electron emission property was also investigated.

Exploring the assumed invariance of implied emission factors for forest biomass in greenhouse gas inventories

International Nuclear Information System (INIS)

Smith, James E.; Heath, Linda S.

2010-01-01

Reviews of each nation's annual greenhouse gas inventory submissions including forestland are part of the ongoing reporting process of the United Nations Framework Convention on Climate Change. Goals of these reviews include improving quality and consistency within and among reports. One method of facilitating comparisons is the use of a standard index such as an implied emission factor (IEF), which for forest biomass indicates net rate of carbon emission or sequestration per area. Guidance on the use of IEFs in reviews is limited, but there is an expectation that values should be relatively constant both over time and across spatial scales. To address this hypothesis, we examine IEFs over time, derived from U.S. forests at plot-, state-, and national-levels. Results show that at increasingly aggregated levels, relative heterogeneity decreases but can still be substantial. A net increase in U.S. whole-forest IEFs over time is consistent with results from temperate forests of nations in the European Community. IEFs are better viewed as a distribution of values rather than one constant value principally because of sensitivities to productivity, disturbance, and land use change, which can all vary considerably across a nation's forest land.

New Tropical Peatland Gas and Particulate Emissions Factors Indicate 2015 Indonesian Fires Released Far More Particulate Matter (but Less Methane than Current Inventories Imply

Directory of Open Access Journals (Sweden)

Martin J. Wooster

2018-03-01

Full Text Available Deforestation and draining of the peatlands in equatorial SE Asia has greatly increased their flammability, and in September–October 2015 a strong El Niño-related drought led to further drying and to widespread burning across parts of Indonesia, primarily on Kalimantan and Sumatra. These fires resulted in some of the worst sustained outdoor air pollution ever recorded, with atmospheric particulate matter (PM concentrations exceeding those considered “extremely hazardous to health” by up to an order of magnitude. Here we report unique in situ air quality data and tropical peatland fire emissions factors (EFs for key carbonaceous trace gases (CO2, CH4 and CO and PM2.5 and black carbon (BC particulates, based on measurements conducted on Kalimantan at the height of the 2015 fires, both at locations of “pure” sub-surface peat burning and spreading vegetation fires atop burning peat. PM2.5 are the most significant smoke constituent in terms of human health impacts, and we find in situ PM2.5 emissions factors for pure peat burning to be 17.8 to 22.3 g·kg−1, and for spreading vegetation fires atop burning peat 44 to 61 g·kg−1, both far higher than past laboratory burning of tropical peat has suggested. The latter are some of the highest PM2.5 emissions factors measured worldwide. Using our peatland CO2, CH4 and CO emissions factors (1779 ± 55 g·kg−1, 238 ± 36 g·kg−1, and 7.8 ± 2.3 g·kg−1 respectively alongside in situ measured peat carbon content (610 ± 47 g-C·kg−1 we provide a new 358 Tg (± 30% fuel consumption estimate for the 2015 Indonesian fires, which is less than that provided by the GFEDv4.1s and GFASv1.2 global fire emissions inventories by 23% and 34% respectively, and which due to our lower EFCH4 produces far less (~3× methane. However, our mean in situ derived EFPM2.5 for these extreme tropical peatland fires (28 ± 6 g·kg−1 is far higher than current emissions inventories assume, resulting in our total

Priority hazardous substances for the aquatic environment: critical evaluation of the emission factor method for the indirect estimate of the loads

International Nuclear Information System (INIS)

Azzellino, A.; Vismara, R.

2005-01-01

The European Water Framework Directive require to the EU Member States the knowledge of the priority hazardous pollutant contamination levels. Regional basin management plans (according to Italian laws D.Lgs 152/99 and to D.M. 367/03) generally include a review about the status of water contamination to respond to the Eu legislation prescriptions. However, since the actual monitoring activity of the water contamination is expensive and also extremely difficult in terms of analytical sensitivity, the most of these reviews has been prepared by using indirect emission coefficient estimates derived form literature. It is well known that such emission coefficients have been rarely proved fully reliable; moreover such an approach gives no information about the variability affecting the emission estimates. Aim of this work was to use the data contained into the emission EPER-INES database, european database which contains the IPPC Directive emission declarations, to define emission coefficients more reliable than literature coefficients. The presented results, even though based on a limited number of observations and referring the most only to heavy metals, confirm the scarce affidability of the emission factor method and show remarkable discrepancies (mostly under- but also over-estimations of about ten-fold) of these emission estimates from the actual emission data of the IPPC declarations. These results allow also to evaluate the not negligible variability that affects the definition of emission coefficients [it

Controlling factors of nitrous oxide (N2O) emissions at the field-scale in an agricultural slope

Science.gov (United States)

Vilain, Guillaume; Garnier, Josette; Tallec, Gaëlle; Tournebize, Julien; Cellier, Pierre; Flipo, Nicolas

2010-05-01

Agricultural practices widely contribute to the atmospheric nitrous oxide (N2O) concentration increase and are the major source of N2O which account for 24% of the global annual emission (IPCC, 2007). Soil nitrification and denitrification are the microbial processes responsible for the production of N2O, which also depends on soil characteristics and management. Besides their control by various factors, such as climate, soil conditions and management (content of NO3- and NH4+, soil water content, presence of degradable organic material…), the role of topography is less known although it can play an important role on N2O emissions (Izaurralde et al., 2004). Due to the scarcity of data on N2O direct vs. indirect emission rate from agriculture in the Seine Basin (Garnier et al., 2009), one of the objectives of the study conducted here was to determine the N2O emission rates of the various land use representative for the Seine Basin, in order to better assess the direct N2O emissions, and to explore controlling factor such as meteorology, topography, soil properties and crop successions. The main objective of this study was at the same time to characterize N2O fluxes variability along a transect from an agricultural plateau to a river and to analyze the influence of landscape position on these emissions. We conducted this study in the Orgeval catchment (Seine basin, France; between 48°47' and 48°55' N, and 03°00' and 03°55' E) from May 2008 to August 2009 on two agricultural fields cropped with wheat, barley, oats, corn. N2O fluxes were monitored from weekly to bimonthly using static manual chambers placed along the chosen transect in five different landscape positions from the plateau to the River. This study has shown that soil moisture (expressed as Water Filled Pore Space) and NO3- soil concentrations explained most of the N2O flux variability during the sampling period. Most of N2O was emitted directly after N fertilization application during a relatively

Two showy traits, scent emission and pigmentation, are finely coregulated by the MYB transcription factor PH4 in petunia flowers.

Science.gov (United States)

Cna'ani, Alon; Spitzer-Rimon, Ben; Ravid, Jasmin; Farhi, Moran; Masci, Tania; Aravena-Calvo, Javiera; Ovadis, Marianna; Vainstein, Alexander

2015-11-01

The mechanism underlying the emission of phenylpropanoid volatiles is poorly understood. Here, we reveal the involvement of PH4, a petunia MYB-R2R3 transcription factor previously studied for its role in vacuolar acidification, in floral volatile emission. We used the virus-induced gene silencing (VIGS) approach to knock down PH4 expression in petunia, measured volatile emission and internal pool sizes by GC-MS, and analyzed transcript abundances of scent-related phenylpropanoid genes in flowers. Silencing of PH4 resulted in a marked decrease in floral phenylpropanoid volatile emission, with a concurrent increase in internal pool levels. Expression of scent-related phenylpropanoid genes was not affected. To identify putative scent-related targets of PH4, we silenced PH5, a tonoplast-localized H(+) -ATPase that maintains vacuolar pH homeostasis. Suppression of PH5 did not yield the reduced-emission phenotype, suggesting that PH4 does not operate in the context of floral scent through regulation of vacuolar pH. We conclude that PH4 is a key floral regulator that integrates volatile production and emission processes and interconnects two essential floral traits - color and scent. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

Source apportionment of PAH in Hamilton Harbour suspended sediments: comparison of two factor analysis methods.

Science.gov (United States)

Sofowote, Uwayemi M; McCarry, Brian E; Marvin, Christopher H

2008-08-15

A total of 26 suspended sediment samples collected over a 5-year period in Hamilton Harbour, Ontario, Canada and surrounding creeks were analyzed for a suite of polycyclic aromatic hydrocarbons and sulfur heterocycles. Hamilton Harbour sediments contain relatively high levels of polycyclic aromatic compounds and heavy metals due to emissions from industrial and mobile sources. Two receptor modeling methods using factor analyses were compared to determine the profiles and relative contributions of pollution sources to the harbor; these methods are principal component analyses (PCA) with multiple linear regression analysis (MLR) and positive matrix factorization (PMF). Both methods identified four factors and gave excellent correlation coefficients between predicted and measured levels of 25 aromatic compounds; both methods predicted similar contributions from coal tar/coal combustion sources to the harbor (19 and 26%, respectively). One PCA factor was identified as contributions from vehicular emissions (61%); PMF was able to differentiate vehicular emissions into two factors, one attributed to gasoline emissions sources (28%) and the other to diesel emissions sources (24%). Overall, PMF afforded better source identification than PCA with MLR. This work constitutes one of the few examples of the application of PMF to the source apportionment of sediments; the addition of sulfur heterocycles to the analyte list greatly aided in the source identification process.

Land and Water Use, CO2 Emissions, and Worker Radiological Exposure Factors for the Nuclear Fuel Cycle

Energy Technology Data Exchange (ETDEWEB)

Brett W Carlsen; Brent W Dixon; Urairisa Pathanapirom; Eric Schneider; Bethany L. Smith; Timothy M. AUlt; Allen G. Croff; Steven L. Krahn

2013-08-01

The Department of Energy Office of Nuclear Energy’s Fuel Cycle Technologies program is preparing to evaluate several proposed nuclear fuel cycle options to help guide and prioritize Fuel Cycle Technology research and development. Metrics are being developed to assess performance against nine evaluation criteria that will be used to assess relevant impacts resulting from all phases of the fuel cycle. This report focuses on four specific environmental metrics. • land use • water use • CO2 emissions • radiological Dose to workers Impacts associated with the processes in the front-end of the nuclear fuel cycle, mining through enrichment and deconversion of DUF6 are summarized from FCRD-FCO-2012-000124, Revision 1. Impact estimates are developed within this report for the remaining phases of the nuclear fuel cycle. These phases include fuel fabrication, reactor construction and operations, fuel reprocessing, and storage, transport, and disposal of associated used fuel and radioactive wastes. Impact estimates for each of the phases of the nuclear fuel cycle are given as impact factors normalized per unit process throughput or output. These impact factors can then be re-scaled against the appropriate mass flows to provide estimates for a wide range of potential fuel cycles. A companion report, FCRD-FCO-2013-000213, applies the impact factors to estimate and provide a comparative evaluation of 40 fuel cycles under consideration relative to these four environmental metrics.

Modelling of NO{sub x} emission factors from heavy and light-duty vehicles equipped with advanced aftertreatment systems

Energy Technology Data Exchange (ETDEWEB)

Oliveira, M.L.M., E-mail: monalisa@unifor.br [IDMEC - Institute of Mechanical Engineering, Instituto Superior Tecnico, Technical University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon (Portugal); Silva, C.M. [IDMEC - Institute of Mechanical Engineering, Instituto Superior Tecnico, Technical University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon (Portugal); Moreno-Tost, R. [Departamento de Quimica Inorganica, Cristalografia y Mineralogia, Unidad Asociada al Instituto de Catalisis, CSIC, Universidad de Malaga, Campus de Teatinos, 29071 Malaga (Spain); Farias, T.L. [IDMEC - Institute of Mechanical Engineering, Instituto Superior Tecnico, Technical University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon (Portugal); Jimenez-Lopez, Antonio [IDMEC - Institute of Mechanical Engineering, Instituto Superior Tecnico, Technical University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon (Portugal); Departamento de Quimica Inorganica, Cristalografia y Mineralogia, Unidad Asociada al Instituto de Catalisis, CSIC, Universidad de Malaga, Campus de Teatinos, 29071 Malaga (Spain); Rodriguez-Castellon, E. [Departamento de Quimica Inorganica, Cristalografia y Mineralogia, Unidad Asociada al Instituto de Catalisis, CSIC, Universidad de Malaga, Campus de Teatinos, 29071 Malaga (Spain)

2011-08-15

Highlights: {yields} Alternative SCR materials. {yields} Catalysts used in heavy-duty vehicles are based on V{sub 2}O{sub 5}-WO{sub 3}-TiO{sub 2}. {yields}Zeolites containing transition metal ions as catalysts for urea SCR has increased. {yields} FeZSM5 catalyst can be a possible candidate as far as pollutants regulation is considered. {yields} Regarding N{sub 2}O emissions mordenite based SCR do not emit this pollutant. - Abstract: NO{sub x} emission standards are becoming stringiest over the world especially for heavy-duty vehicles. To comply with current and future regulations some vehicle manufacturers are adopting exhaust aftertreatment systems known as Selective Catalytic Reduction (SCR). The catalysts are based on Vanadium (Va) and the reductant agent based on ammonia. However, Va is listed on the California Proposition 65 List as potentially causing cancer and alternatives are being studied. This paper presents a model based on neural networks that integrated with a road vehicle simulator allows to estimate NO{sub x} emission factors for different powertrain configurations, along different driving conditions, and covering commercial, zeolite and mordenite alternatives as the base monolith for SCR. The research included the experimental study of copper based and iron based zeolites (ZSM5 and Cuban natural mordenite). The response of NO{sub x} conversion efficiency was monitored in a laboratory for varying space velocity, oxygen, sulfur, water, NO{sub x} and SO{sub 2} emulating the conditions of a Diesel engine exhaust along a trip. The experimental data was used for training neural networks and obtaining a mathematical correlation between the outputs and inputs of the SCR system. The developed correlation was integrated with ADVISOR road vehicle simulator to obtain NO{sub x} emission factors and to test each SCR system installed on light-duty and heavy-duty vehicles for standardized driving cycles and real measured driving cycles. Despite having lower NO

Emission factors of air pollutants from CNG-gasoline bi-fuel vehicles: Part II. CO, HC and NOx.

Science.gov (United States)

Huang, Xiaoyan; Wang, Yang; Xing, Zhenyu; Du, Ke

2016-09-15

The estimation of emission factors (EFs) is the basis of accurate emission inventory. However, the EFs of air pollutants for motor vehicles vary under different operating conditions, which will cause uncertainty in developing emission inventory. Natural gas (NG), considered as a "cleaner" fuel than gasoline, is increasingly being used to reduce combustion emissions. However, information is scarce about how much emission reduction can be achieved by motor vehicles burning NG (NGVs) under real road driving conditions, which is necessary for evaluating the environmental benefits for NGVs. Here, online, in situ measurements of the emissions from nine bi-fuel vehicles were conducted under different operating conditions on the real road. A comparative study was performed for the EFs of black carbon (BC), carbon monoxide (CO), hydrocarbons (HCs) and nitrogen oxides (NOx) for each operating condition when the vehicles using gasoline and compressed NG (CNG) as fuel. BC EFs were reported in part I. The part II in this paper series reports the influence of operating conditions and fuel types on the EFs of CO, HC and NOx. Fuel-based EFs of CO showed good correlations with speed when burning CNG and gasoline. The correlation between fuel-based HC EFs and speed was relatively weak whether burning CNG or gasoline. The fuel-based NOx EFs moderately correlated with speed when burning CNG, but weakly correlated with gasoline. As for HC, the mileage-based EFs of gasoline vehicles are 2.39-12.59 times higher than those of CNG vehicles. The mileage-based NOx EFs of CNG vehicles are slightly higher than those of gasoline vehicles. These results would facilitate a detailed analysis of the environmental benefits for replacing gasoline with CNG in light duty vehicles. Copyright © 2016 Elsevier B.V. All rights reserved.

Individual-motivational factors in the acceptability of demand-side and supply-side measures to reduce carbon emissions

International Nuclear Information System (INIS)

Poortinga, Wouter; Spence, Alexa; Demski, Christina; Pidgeon, Nick F.

2012-01-01

As more than a third of all carbon dioxide emissions in the UK are generated by the domestic sector, individuals need to make drastic changes to their current lifestyle in order to play their part in climate change mitigation. Not only do they need to change their personal behaviour, they also have to accept new low-carbon technologies in order to decarbonise the energy they are using. This study uses an adapted version of the Value–Belief-Norm (VBN) model () to examine individual-motivational factors in the acceptability of demand-side and supply-side strategies to reduce carbon emissions. The study found that environmental identity, climate change concern, and personal norms are all significantly associated with the acceptability of both demand-side measures and supply-side technologies. While personal values were also important, their associations were mediated by more specific factors. Overall, the adapted VBN model was better able to explain the acceptability of low-carbon behaviours than of low-carbon energy-supply technologies. Concern about energy security appeared to be of limited importance. It was negatively associated with the willingness to engage in low-carbon behaviours, suggesting that a shift in focus towards energy security issues may not necessarily help a transition to a low-carbon society. - Highlights: ► An adapted VBN model is proposed to study environmentally significant behaviour.► Environmental identity is important for both demand-side and supply-side measures.► Energy security concern is of limited importance to support for supply-side measures.► Energy security concern reduces the willingness to engage in low-carbon behaviours.

Emission factor of gases from the greenhouse effect for the brazilian interconnected system; Fator de emissao de gases de efeito estufa para o sistema interligado brasileiro

Energy Technology Data Exchange (ETDEWEB)

Esparta, A. Ricardo J. [Ecoinvest Carbon S.A., Sao Paulo, SP (Brazil)]. E-mail: esparta@iee.usp.br; esparta@ecoinvestcarbon.com; Fernandez, Pablo [EcoSecurities, Rio de Janeiro, RJ (Brazil)]. E-mail: pablo.fernandez@ecosecurities.com.br; Costa, David Freire da [Econergy Brasil, Sao Paulo, SP (Brazil)]. E-mail: freire@econergy.com.br

2006-07-01

The participation of new power generation projects of the Brazilian interconnected system in the Clean Development Mechanism of the Kyoto Protocol demand the definition of greenhouse gases baseline emission scenarios and monitoring methodologies. The present paper describes the reasoning behind approved methodologies for capacity addition from renewable sources as well as carries out the calculation of the emission factor for the Brazilian interconnected grid. (author)

Tissue factor-dependent activation of tritium-labeled factor IX and factor X in human plasma

International Nuclear Information System (INIS)

Morrison, S.A.; Jesty, J.

1984-01-01

A comparism was made of the tissue factor-dependent activation of tritium-labeled factor IX and factor X in a human plasma system and a study was made of the role of proteases known to stimulate factor VII activity. Plasma was defibrinated by heating and depleted of its factors IX and X by passing it through antibody columns. Addition of human brain thromboplastin, Ca2+, and purified 3H-labeled factor X to the plasma resulted, after a short lag, in burst-like activation of the factor X, measured as the release of radiolabeled activation peptide. The progress of activation was slowed by both heparin and a specific inhibitor of factor Xa but factor X activation could not be completely abolished by such inhibitors. In the case of 3H-factor IX activation, the rate also increased for approximately 3 min after addition of thromboplastin, but was not subsequently curtailed. A survey of proteases implicated as activators of factor VII in other settings showed that both factor Xa and factor IXa could accelerate the activation of factor IX. However, factor Xa was unique in obliterating activation when present at concentrations greater than approximately 1 nM. Heparin inhibited the tissue factor-dependent activation of factor IX almost completely, apparently through the effect of antithrombin on the feedback reactions of factors Xa and IXa on factor VII. These results suggest that a very tight, biphasic control of factor VII activity exists in human plasma, which is modulated mainly by factor Xa. At saturation of factor VIIa/tissue factor, factor IX activation was significantly more rapid than was previously found in bovine plasma under similar conditions. The activation of factor X at saturation was slightly more rapid than in bovine plasma, despite the presence of heparin

Development of South African vehicle emission factors

CSIR Research Space (South Africa)

Forbes, P

2009-10-01

Full Text Available for each pollutant, which have been derived from monitoring campaigns in Europe and the USA. In this study, direct exhaust emission monitoring was performed on 58 diesel and 78 petrol passenger vehicles in both idling and accelerated modes. South African...

Implications of diesel emissions control failures to emission factors and road transport NOx evolution

NARCIS (Netherlands)

Ntziachristos, L.; Papadimitriou, G.; Ligterink, N.; Hausberger, S.

2016-01-01

Diesel NOx emissions have been at the forefront of research and regulation scrutiny as a result of failures of late vehicle technologies to deliver on-road emissions reductions. The current study aims at identifying the actual emissions levels of late light duty vehicle technologies, including Euro

Updated US and Canadian normalization factors for TRACI 2.1

DEFF Research Database (Denmark)

Ryberg, Morten; Vieira, Marisa D. M.; Zgola, Melissa

2014-01-01

When LCA practitioners perform LCAs, the interpretation of the results can be difficult without a reference point to benchmark the results. Hence, normalization factors are important for relating results to a common reference. The main purpose of this paper was to update the normalization factors...... for the US and US-Canadian regions. The normalization factors were used for highlighting the most contributing substances, thereby enabling practitioners to put more focus on important substances, when compiling the inventory, as well as providing them with normalization factors reflecting the actual...... situation. Normalization factors were calculated using characterization factors from the TRACI 2.1 LCIA model. The inventory was based on US databases on emissions of substances. The Canadian inventory was based on a previous inventory with 2005 as reference, in this inventory the most significant...

[Investigation of emission characteristics for light duty vehicles with a portable emission measurement system].

Science.gov (United States)

Wang, Hai-Kun; Fu, Li-Xin; Zhou, Yu; Lin, Xin; Chen, Ai-Zhong; Ge, Wei-hu; Du, Xuan

2008-10-01

Emission from 7 typical light-duty vehicles under actual driving conditions was monitored using a portable emission measurement system to gather data for characterization of the real world vehicle emission in Shenzhen, including the effects of driving modes on vehicle emission, comparison of fuel consumption based emission factors (g x L(-1) with mileage based emission factors (g x km(-1)), and the average emission factors of the monitored vehicles. The acceleration and deceleration modes accounted for 66.7% of total travel time, 80.3% of traveling distance and 74.6%-79.2% of vehicle emission; the acceleration mode contributed more than other driving modes. The fuel based emission factors were less dependent on the driving speed; they may be utilized in building macro-scale vehicle emission inventory with smaller sensitivity to the vehicle driving conditions. The effect of vehicle technology on vehicle emission was significant; the emission factors of CO, HC and NO(x) of carbureted vehicles were 19.9-20.5, 5.6-26.1 and 1.8-2.0 times the more advanced vehicles of Euro II, respectively. Using the ECE + EUDC driving cycle would not produce the desired real-world emission rates of light duty vehicles in a typical Chinese city.

Factors and factorizations of graphs proof techniques in factor theory

CERN Document Server

Akiyama, Jin

2011-01-01

This book chronicles the development of graph factors and factorizations. It pursues a comprehensive approach, addressing most of the important results from hundreds of findings over the last century. One of the main themes is the observation that many theorems can be proved using only a few standard proof techniques. This stands in marked contrast to the seemingly countless, complex proof techniques offered by the extant body of papers and books. In addition to covering the history and development of this area, the book offers conjectures and discusses open problems. It also includes numerous explanatory figures that enable readers to progressively and intuitively understand the most important notions and proofs in the area of factors and factorization.

Correction factor for hair analysis by PIXE

International Nuclear Information System (INIS)

Montenegro, E.C.; Baptista, G.B.; Castro Faria, L.V. de; Paschoa, A.S.

1980-01-01

The application of the Particle Induced X-ray Emission (PIXE) technique to analyse quantitatively the elemental composition of hair specimens brings about some difficulties in the interpretation of the data. The present paper proposes a correction factor to account for the effects of the energy loss of the incident particle with penetration depth, and X-ray self-absorption when a particular geometrical distribution of elements in hair is assumed for calculational purposes. The correction factor has been applied to the analysis of hair contents Zn, Cu and Ca as a function of the energy of the incident particle. (orig.)

Correction factor for hair analysis by PIXE

International Nuclear Information System (INIS)

Montenegro, E.C.; Baptista, G.B.; Castro Faria, L.V. de; Paschoa, A.S.

1979-06-01

The application of the Particle Induced X-ray Emission (PIXE) technique to analyse quantitatively the elemental composition of hair specimens brings about some difficulties in the interpretation of the data. The present paper proposes a correction factor to account for the effects of energy loss of the incident particle with penetration depth, and x-ray self-absorption when a particular geometrical distribution of elements in hair is assumed for calculational purposes. The correction factor has been applied to the analysis of hair contents Zn, Cu and Ca as a function of the energy of the incident particle.(Author) [pt

Sensitivity analyses of factors influencing CMAQ performance for fine particulate nitrate.

Science.gov (United States)

Shimadera, Hikari; Hayami, Hiroshi; Chatani, Satoru; Morino, Yu; Mori, Yasuaki; Morikawa, Tazuko; Yamaji, Kazuyo; Ohara, Toshimasa

2014-04-01

Improvement of air quality models is required so that they can be utilized to design effective control strategies for fine particulate matter (PM2.5). The Community Multiscale Air Quality modeling system was applied to the Greater Tokyo Area of Japan in winter 2010 and summer 2011. The model results were compared with observed concentrations of PM2.5 sulfate (SO4(2-)), nitrate (NO3(-)) and ammonium, and gaseous nitric acid (HNO3) and ammonia (NH3). The model approximately reproduced PM2.5 SO4(2-) concentration, but clearly overestimated PM2.5 NO3(-) concentration, which was attributed to overestimation of production of ammonium nitrate (NH4NO3). This study conducted sensitivity analyses of factors associated with the model performance for PM2.5 NO3(-) concentration, including temperature and relative humidity, emission of nitrogen oxides, seasonal variation of NH3 emission, HNO3 and NH3 dry deposition velocities, and heterogeneous reaction probability of dinitrogen pentoxide. Change in NH3 emission directly affected NH3 concentration, and substantially affected NH4NO3 concentration. Higher dry deposition velocities of HNO3 and NH3 led to substantial reductions of concentrations of the gaseous species and NH4NO3. Because uncertainties in NH3 emission and dry deposition processes are probably large, these processes may be key factors for improvement of the model performance for PM2.5 NO3(-). The Community Multiscale Air Quality modeling system clearly overestimated the concentration of fine particulate nitrate in the Greater Tokyo Area of Japan, which was attributed to overestimation of production of ammonium nitrate. Sensitivity analyses were conducted for factors associated with the model performance for nitrate. Ammonia emission and dry deposition of nitric acid and ammonia may be key factors for improvement of the model performance.

Evaluation of Amyloid Protective Factors and Alzheimer Disease Neurodegeneration Protective Factors in Elderly Individuals.

Science.gov (United States)

Vemuri, Prashanthi; Knopman, David S; Lesnick, Timothy G; Przybelski, Scott A; Mielke, Michelle M; Graff-Radford, Jonathan; Murray, Melissa E; Roberts, Rosebud O; Vassilaki, Maria; Lowe, Val J; Machulda, Mary M; Jones, David T; Petersen, Ronald C; Jack, Clifford R

2017-06-01

While amyloid and neurodegeneration are viewed together as Alzheimer disease pathophysiology (ADP), the factors that influence amyloid and AD-pattern neurodegeneration may be considerably different. Protection from these ADP factors may be important for aging without significant ADP. To identify the combined and independent protective factors for amyloid and AD-pattern neurodegeneration in a population-based sample and to test the hypothesis that "exceptional agers" with advanced ages do not have significant ADP because they have protective factors for amyloid and neurodegeneration. This cohort study conducted a prospective analysis of 942 elderly individuals (70-≥90 years) with magnetic resonance imaging and Pittsburgh compound B-positron emission tomography scans enrolled in the Mayo Clinic Study of Aging, a longitudinal population-based study of cognitive aging in Olmsted County, Minnesota. We operationalized "exceptional aging" without ADP by considering individuals 85 years or older to be without significant evidence of ADP. We evaluated predictors including demographics, APOE, intellectual enrichment, midlife risk factors (physical inactivity, obesity, smoking, diabetes, hypertension, and dyslipidemia), and the total number of late-life cardiac and metabolic conditions. We used multivariate linear regression models to identify the combined and independent protective factors for amyloid and AD-pattern neurodegeneration. Using a subsample of the cohort 85 years of age or older, we computed Cohen d-based effect size estimations to compare the quantitative strength of each predictor variable in their contribution with exceptional aging without ADP. The study participants included 423 (45%) women and the average age of participants was 79.7 (5.9) years. Apart from demographics and the APOE genotype, only midlife dyslipidemia was associated with amyloid deposition. Obesity, smoking, diabetes, hypertension, and cardiac and metabolic conditions, but not

Combustion efficiency and emission factors for wildfire-season fires in mixed conifer forests of the northern Rocky Mountains, US

Directory of Open Access Journals (Sweden)

S. P. Urbanski

2013-07-01

Full Text Available In the US, wildfires and prescribed burning present significant challenges to air regulatory agencies attempting to achieve and maintain compliance with air quality regulations. Fire emission factors (EF are essential input for the emission models used to develop wildland fire emission inventories. Most previous studies quantifying wildland fire EF of temperate ecosystems have focused on emissions from prescribed burning conducted outside of the wildfire season. Little information is available on EF for wildfires in temperate forests of the conterminous US. The goal of this work is to provide information on emissions from wildfire-season forest fires in the northern Rocky Mountains, US. In August 2011, we deployed airborne chemistry instruments and sampled emissions over eight days from three wildfires and a prescribed fire that occurred in mixed conifer forests of the northern Rocky Mountains. We measured the combustion efficiency, quantified as the modified combustion efficiency (MCE, and EF for CO2, CO, and CH4. Our study average values for MCE, EFCO2, EFCO, and EFCH4 were 0.883, 1596 g kg−1, 135 g kg−1, 7.30 g kg−1, respectively. Compared with previous field studies of prescribed fires in temperate forests, the fires sampled in our study had significantly lower MCE and EFCO2 and significantly higher EFCO and EFCH4. The fires sampled in this study burned in areas reported to have moderate to heavy components of standing dead trees and down dead wood due to insect activity and previous fire, but fuel consumption data was not available. However, an analysis of MCE and fuel consumption data from 18 prescribed fires reported in the literature indicates that the availability of coarse fuels and conditions favorable for the combustion of these fuels favors low MCE fires. This analysis suggests that fuel composition was an important factor contributing to the low MCE of the fires measured in this study. This study only measured EF for CO2, CO

Factor XII (Hageman factor) deficiency

Science.gov (United States)

... this page: //medlineplus.gov/ency/article/000545.htm Factor XII (Hageman factor) deficiency To use the sharing features on this ... M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health ...

Estimating greenhouse gas emissions using emission factors from the Sugarcane Development Company, Ahvaz, Iran

Directory of Open Access Journals (Sweden)

Amir Zahedi

2018-05-01

Full Text Available Background: Greenhouse gas (GHG emissions are increasing worldwide. They have harmful effects on human health, animals, and plants and play a major role in global warming and acid rain. Methods: This research investigated carbon dioxide (CO2 and CH4 emissions obtained from different parts of the Hakim Farabi, Dobal Khazaei, and Ramin factories which produce ethanol and yeast. Seasonal rates of CO2 at the soil surface at the studied sites were estimated from measurements made on location and at intervals with manual chambers. This study aimed to assess the production rate of GHG emissions (CH4, CO2 in the sugar production units of Hakim Farabi, Dobal Khazaei, and Ramin factories. Results: Mean concentrations of CO2 and CH4 emissions are respectively 279 500.207 and 3087.07 tons/ year from the Hakim Farabi agro-industry, 106 985.24 and 1.14 tons/year at the Dobal Khazaei ethanol producing factory, and 124 766.17 and 1.93 tons/year at the Ramin leavening producing factory. Conclusion: Sugar plant boilers and the burning of sugarcane contributed the most CO2 and CH4 emissions, respectively. Moreover, lime kilns and diesel generators showed the least carbon dioxide and methane emissions, respectively.

Factors affecting the carbon allowance market in the US

Energy Technology Data Exchange (ETDEWEB)

Kim, Hyun Seok; Koo, Won W. [Center for Agricultural Policy and Trade Studies, Department of Agribusiness and Applied Economics, North Dakota State University, Dept 7610, P.O. Box 6050, Fargo, ND 58103-6050 (United States)

2010-04-15

The US carbon allowance market has different characteristic and price determination process from the EU ETS market, since emitting installations voluntarily participate in emission trading scheme. This paper examines factors affecting the US carbon allowance market. An autoregressive distributed lag model is used to examine the short- and long-run relationships between the US carbon allowance market and its determinant factors. In the long-run, the price of coal is a main factor in the determination of carbon allowance trading. In the short-run, on the other hand, the changes in crude oil and natural gas prices as well as coal price have significant effects on carbon allowance market. (author)

Factors affecting the carbon allowance market in the US

International Nuclear Information System (INIS)

Kim, Hyun Seok; Koo, Won W.

2010-01-01

The US carbon allowance market has different characteristic and price determination process from the EU ETS market, since emitting installations voluntarily participate in emission trading scheme. This paper examines factors affecting the US carbon allowance market. An autoregressive distributed lag model is used to examine the short- and long-run relationships between the US carbon allowance market and its determinant factors. In the long-run, the price of coal is a main factor in the determination of carbon allowance trading. In the short-run, on the other hand, the changes in crude oil and natural gas prices as well as coal price have significant effects on carbon allowance market.

Factor 4 planning

International Nuclear Information System (INIS)

Bariol-Mathais, Brigitte; Lavoillotte, Philippine; Gall-Sorrentino, Florence; Malez, Marianne; Sanna, Daniela; Marsauche, Maud; Marquet, Sarah; Debergue, Sophie; Aminu, Olufunmi; Bernard, Helene; Marchand, Jean-Michel; Blin, Frederic; Grange, Jerome; Caillierez, Sophie; Muller, Dania; Clement, Bob; Desire, Jean-Charles; Metais, Benedicte; Lannuzel, Philippe; Pezet-Kuhn, Murielle; Pons, Anne; Rivoire-Meley, Benedicte; Tissot, Heloise

2015-07-01

Factor 4 is the goal of cutting our greenhouse gas emissions by 75% by 2050. Achieving this objective will necessitate radical changes in our practices, in particular concerning transport and housing; the measures currently implemented, such as positive-energy buildings, low-impact mobility and eco-neighbourhoods, will not be enough to meet this goal. These measures must be conceived in the framework of broad territorial planning that integrates environmental and energy objectives far upstream. To this end, the French Environment and Energy Management Agency (ADEME) and the French network of Urban Planning Agencies (FNAU), pursuing their missions in their respective areas of competence, have joined forces to make infrastructure and land use planning an integral part of the environmental and energy transition process. In 2013, the two organisations signed a partnership agreement and compiled an inventory of practices that are relevant to Factor 4 planning. This work was led by Epures, Saint-etienne urban planning agency, along with FNAU, drawing upon the expertise of a dozen urban planning agencies in precursor territories. This inventory describes the stakes, resources and strengths for each territory, which have led to cross-sectoral territorial planning exercises with ambitious environmental and energy objectives; the importance of evaluation in attaining these goals is emphasised. Current experience, questions and available methodological tools are summarised in this document, to encourage territories and help them design their planning policies along a trajectory to achieve Factor 4 goals. The compilation also aims to be a contribution to the COP21 climate conference

Policies for Promotion of Electric Vehicles and Factors Influencing Consumers’ Purchasing Decisions of Low Emission Vehicles

Directory of Open Access Journals (Sweden)

Matjaz Knez

2017-06-01

Full Text Available Recently different studies of green transport have become interesting for policy makers,car manufacturers, customers and energy suppliers. Many stakeholders from the publicand private sectors are investing a lot of effort to identify consumer behaviour for futureimprovements in development of green products and effective strategies, which couldaccelerate the transition to sustainable future. This paper presents the effects of electricvehicle promotional policies and customer preferences about alternative fuel vehicles.This study has shown that the electric vehicle promotional policies adopted in Sloveniahave been unsuccessful, as the share of first-time registered electric vehicles in 2013 wasbelow 1%. For different segments of people whose opinions about low emission vehiclesdiffer, different measures must be adopted. When designing promotional policies focusmust be on the most relevant factors such as the total vehicle price and fuel economy.

Factors Affecting Aerosol Radiative Forcing from Both Production-based and Consumption-based View

Science.gov (United States)

Wang, J.; Lin, J.; Ni, R.

2017-12-01

Aerosol radiative forcing (RF) is determined by emissions and various chemical-transport-radiative processes in the atmosphere, a multi-factor problem whose individual contributors have not been well quantified. This problem becomes more complicated when taking into account the role of international trade, which means reallocated aerosol RF due to separation of regions producing goods and emissions and regions consuming those goods. Here we analyze major factors affecting RF of secondary inorganic aerosols (SIOAs, including sulfate, nitrate and ammonium), primary organic aerosol (POA) and black carbon (BC), extending the work of Lin et al. (2016, Nature Geoscience). We contrast five factors determining production-based (RFp, due to a region's production of goods) and consumption-based (RFc, due to a region's consumption) forcing by 11 major regions, including population size, per capita output, emission intensity (emission per output), chemical efficiency (mass per unit emission) and radiative efficiency (RF per unit mass). Comparing across the 11 regions, East Asia produces the strongest RFp and RFc of SIOA and BC and the second largest RFp and RFc of POA primarily due to its high emission intensity. Although Middle East and North Africa has low emissions, its RFp is strengthened by its largest chemical efficiency for POA and BC and second largest chemical efficiency for SIOA. However, RFp of South-East Asia and Pacific is greatly weakened by its lowest chemical efficiency. Economic trade means that net importers (Western Europe, North America and Pacific OECD) have higher RFc than RFp by 50-100%. And such forcing difference is mainly due to the high emission intensity of the exporters supplying these regions. For North America, SIOA's RFc is 50% stronger than RFp, for that emission intensity of SIOA is 5.2 times in East Asia and 2.5 times in Latin America and Caribbean compared with that in North America, and the chemical efficiency in the top four exporters are

Coupling field and laboratory measurements to estimate the emission factors of identified and unidentified trace gases for prescribed fires

Directory of Open Access Journals (Sweden)

R. J. Yokelson

2013-01-01

Full Text Available An extensive program of experiments focused on biomass burning emissions began with a laboratory phase in which vegetative fuels commonly consumed in prescribed fires were collected in the southeastern and southwestern US and burned in a series of 71 fires at the US Forest Service Fire Sciences Laboratory in Missoula, Montana. The particulate matter (PM_2.5 emissions were measured by gravimetric filter sampling with subsequent analysis for elemental carbon (EC, organic carbon (OC, and 38 elements. The trace gas emissions were measured by an open-path Fourier transform infrared (OP-FTIR spectrometer, proton-transfer-reaction mass spectrometry (PTR-MS, proton-transfer ion-trap mass spectrometry (PIT-MS, negative-ion proton-transfer chemical-ionization mass spectrometry (NI-PT-CIMS, and gas chromatography with MS detection (GC-MS. 204 trace gas species (mostly non-methane organic compounds (NMOC were identified and quantified with the above instruments. Many of the 182 species quantified by the GC-MS have rarely, if ever, been measured in smoke before. An additional 153 significant peaks in the unit mass resolution mass spectra were quantified, but either could not be identified or most of the signal at that molecular mass was unaccounted for by identifiable species.

In a second, "field" phase of this program, airborne and ground-based measurements were made of the emissions from prescribed fires that were mostly located in the same land management units where the fuels for the lab fires were collected. A broad variety, but smaller number of species (21 trace gas species and PM_2.5 was measured on 14 fires in chaparral and oak savanna in the southwestern US, as well as pine forest understory in the southeastern US and Sierra Nevada mountains of California. The field measurements of emission factors (EF are useful both for modeling and to examine the representativeness of our lab fire EF. The lab EF/field EF ratio for

Minimization of the effect of errors in approximate radiation view factors

International Nuclear Information System (INIS)

Clarksean, R.; Solbrig, C.

1993-01-01

The maximum temperature of irradiated fuel rods in storage containers was investigated taking credit only for radiation heat transfer. Estimating view factors is often easy but in many references the emphasis is placed on calculating the quadruple integrals exactly. Selecting different view factors in the view factor matrix as independent, yield somewhat different view factor matrices. In this study ten to twenty percent error in view factors produced small errors in the temperature which are well within the uncertainty due to the surface emissivities uncertainty. However, the enclosure and reciprocity principles must be strictly observed or large errors in the temperatures and wall heat flux were observed (up to a factor of 3). More than just being an aid for calculating the dependent view factors, satisfying these principles, particularly reciprocity, is more important than the calculation accuracy of the view factors. Comparison to experiment showed that the result of the radiation calculation was definitely conservative as desired in spite of the approximations to the view factors

Transportation Energy Futures Series: Effects of the Built Environment on Transportation: Energy Use, Greenhouse Gas Emissions, and Other Factors

Energy Technology Data Exchange (ETDEWEB)

Porter, C. D.; Brown, A.; Dunphy, R. T.; Vimmerstedt, L.

2013-03-01

Planning initiatives in many regions and communities aim to reduce transportation energy use, decrease emissions, and achieve related environmental benefits by changing land use. This report reviews and summarizes findings from existing literature on the relationship between the built environment and transportation energy use and greenhouse gas emissions, identifying results trends as well as potential future actions. The indirect influence of federal transportation and housing policies, as well as the direct impact of municipal regulation on land use are examined for their effect on transportation patterns and energy use. Special attention is given to the 'four D' factors of density, diversity, design and accessibility. The report concludes that policy-driven changes to the built environment could reduce transportation energy and GHG emissions from less than 1% to as much as 10% by 2050, the equivalent of 16%-18% of present-day urban light-duty-vehicle travel. This is one of a series of reports produced as a result of the Transportation Energy Futures (TEF) project, a Department of Energy-sponsored multi-agency project initiated to pinpoint underexplored strategies for abating GHGs and reducing petroleum dependence related to transportation.

Transportation Energy Futures Series. Effects of the Built Environment on Transportation. Energy Use, Greenhouse Gas Emissions, and Other Factors

Energy Technology Data Exchange (ETDEWEB)

Porter, C. D. [National Renewable Energy Lab. (NREL) and Cambridge Systematics, Inc., Golden, CO (United States); Brown, A. [National Renewable Energy Lab. (NREL) and Cambridge Systematics, Inc., Golden, CO (United States); Dunphy, R. T. [National Renewable Energy Lab. (NREL) and Cambridge Systematics, Inc., Golden, CO (United States); Vimmerstedt, L. [National Renewable Energy Lab. (NREL) and Cambridge Systematics, Inc., Golden, CO (United States)

2013-03-15

Planning initiatives in many regions and communities aim to reduce transportation energy use, decrease emissions, and achieve related environmental benefits by changing land use. This report reviews and summarizes findings from existing literature on the relationship between the built environment and transportation energy use and greenhouse gas emissions, identifying results trends as well as potential future actions. The indirect influence of federal transportation and housing policies, as well as the direct impact of municipal regulation on land use are examined for their effect on transportation patterns and energy use. Special attention is given to the 'four D' factors of density, diversity, design and accessibility. The report concludes that policy-driven changes to the built environment could reduce transportation energy and GHG emissions from less than 1% to as much as 10% by 2050, the equivalent of 16%-18% of present-day urban light-duty-vehicle travel. This is one of a series of reports produced as a result of the Transportation Energy Futures (TEF) project, a Department of Energy-sponsored multi-agency project initiated to pinpoint underexplored strategies for abating GHGs and reducing petroleum dependence related to transportation.

Measuring the Total-Factor Carbon Emission Performance of Industrial Land Use in China Based on the Global Directional Distance Function and Non-Radial Luenberger Productivity Index

Directory of Open Access Journals (Sweden)

Wei Wang

2016-04-01

Full Text Available Industry is a major contributor to carbon emissions in China, and industrial land is an important input to industrial production. Therefore, a detailed analysis of the carbon emission performance of industrial land use is necessary for making reasonable carbon reduction policies that promote the sustainable use of industrial land. This paper aims to analyze the dynamic changes in the total-factor carbon emission performance of industrial land use (TCPIL in China by applying a global directional distance function (DDF and non-radial Luenberger productivity index. The empirical results show that the eastern region enjoys better TCPIL than the central and western regions, but the regional gaps in TCPIL are narrowing. The growth in NLCPILs (non-radial Luenberger carbon emission performance of industrial land use in the eastern and central regions is mainly driven by technological progress, whereas efficiency improvements contribute more to the growth of NLCPIL in the western region. The provinces in the eastern region have the most innovative and environmentally-friendly production technologies. The results of the analysis of the influencing factors show implications for improving the NLCPIL, including more investment in industrial research and development (R&D, the implementation of carbon emission reduction policies, reduction in the use of fossil energy, especially coal, in the process of industrial production, actively learning about foreign advanced technology, properly solving the problem of surplus labor in industry and the expansion of industrial development.

Coupling field and laboratory measurements to estimate the emission factors of identified and unidentified trace gases for prescribed fires

Energy Technology Data Exchange (ETDEWEB)

Yokelson, R. J.; Burling, I. R.; Gilman, J. B.; Warneke, C.; Stockwell, C. E.; de Gouw, J.; Akagi, S. K.; Urbanski, S. P.; Veres, P.; Roberts, J. M.; Kuster, W. C.; Reardon, J.; Griffith, D. W. T.; Johnson, T. J.; Hosseini, S.; Miller, J. W.; Cocker III, D. R.; Jung, H.; Weise, D. R.

2013-01-01

Vegetative fuels commonly consumed in prescribed fires were collected from five locations in the southeastern and southwestern U.S. and burned in a series of 77 fires at the U.S. Forest Service Fire Sciences Laboratory in Missoula, Montana. The particulate matter (PM2.5) emissions were measured by gravimetric filter sampling with subsequent analysis for elemental carbon (EC), organic carbon (OC), and 38 elements. The trace gas emissions were measured with a large suite of state-of-the-art instrumentation including an open-path Fourier transform infrared (OP FTIR) spectrometer, proton-transfer-reaction mass spectrometry (PTR-MS), proton-transfer ion-trap mass spectrometry (PIT-MS), negative-ion proton-transfer chemical-ionization mass spectrometry (NI-PT-CIMS), and gas chromatography with MS detection (GC-MS). 204 trace gas species (mostly non-methane organic compounds (NMOC)) were identified and quantified with the above instruments. An additional 152 significant peaks in the unit mass resolution mass spectra were quantified, but either could not be identified or most of the signal at that molecular mass was unaccounted for by identifiable species. As phase II of this study, we conducted airborne and ground-based sampling of the emissions from real prescribed fires mostly in the same land management units where the fuels for the lab fires were collected. A broad variety, but smaller number of species (21 trace gas species and PM2.5) was measured on 14 fires in chaparral and oak savanna in the southwestern US, as well as pine forest understory in the southeastern US and Sierra Nevada mountains of California. These extensive field measurements of emission factors (EF) for temperate biomass burning are useful both for modeling and to examine the representativeness of our lab fire EF. The lab/field EF ratio for the pine understory fuels was not statistically different from one, on average. However, our lab EF for “smoldering compounds” emitted by burning the semi

Development of emission factors for motorcycles and shared auto-rickshaws using real-world driving cycle for a typical Indian city.

Science.gov (United States)

Adak, Prasenjit; Sahu, Ravi; Elumalai, Suresh Pandian

2016-02-15

Vehicular emission is one of the most important contributors of urban air pollution. To quantify the impact of traffic on urban air quality, it is necessary to quantify vehicular emission. In many cities of India, such as Dhanbad, shared auto-rickshaw is the pre-dominant mode of transportation. Indian Driving Cycle (IDC) and Modified Indian Driving Cycle (MIDC) are used for emission testing of motorcycles, shared auto-rickshaws and passenger cars in India for regulatory purposes. IDC used for motorcycles and shared auto-rickshaws does not recognize the difference in two vehicle classes in terms of driving pattern. In real world, shared auto-rickshaws, behave differently than motorcycles. To quantify the impact of shared auto-rickshaws on urban air quality accurately, emission factors (EFs) are required to derive from real-world driving cycles (DCs). In heterogeneous traffic, vehicles of one class affect the behavior of vehicles of other classes. To estimate the emissions from different vehicle classes accurately, EFs for motorcycles and passenger cars are also required to be revised. In this study, real-world DCs were developed for motorcycles, shared auto-rickshaws and passenger cars in Dhanbad. Developed DCs were used to calculate EFs for respective classes. Shared auto-rickshaws were found to have the highest deviation from EFs derived using IDC. Copyright © 2015 Elsevier B.V. All rights reserved.

Investigation on environmental factors of waste plastics into oil and its emulsion to control the emission in DI diesel engine.

Science.gov (United States)

Kumar, P Senthil; Sankaranarayanan, G

2016-12-01

Rapid depletion of conventional fossil fuel resources, their rising prices and environmental issues are the major concern of alternative fuels. On the other hand waste plastics cause a very serious environmental dispute because of their disposal problems. Waste plastics are one of the promising factors for fuel production because of their high heat of combustion and their increasing availability in local communities. In this study, waste plastic oil (WPO) is tested in DI diesel engine to evaluate its performance and emission characteristics. Results showed that oxides of nitrogen (NO x ) emission get increased with WPO when compared to diesel oil. Further, the three phase (O/W/O) plastic oil emulsion is prepared with an aid of ultrasonicater according to the %v (10, 20 & 30). Results expose that brake thermal efficiency (BTE) is found to be increased. NO x and smoke emissions were reduced up to 247ppm and 41% respectively, when compared to diesel at full load condition with use of 30% emulsified WPO. Copyright © 2016 Elsevier Inc. All rights reserved.

Emission factors of polycyclic and nitro-polycyclic aromatic hydrocarbons from residential combustion of coal and crop residue pellets.

Science.gov (United States)

Yang, Xiaoyang; Liu, Shijie; Xu, Yisheng; Liu, Yu; Chen, Lijiang; Tang, Ning; Hayakawa, Kazuichi

2017-12-01

Polycyclic aromatic hydrocarbons (PAHs) and nitro-polycyclic aromatic hydrocarbons (NPAHs) are toxic pollutants mainly produced during fossil fuel combustion. Domestic coal stoves, which emit large amounts of PAHs and NPAHs, are widely used in the Chinese countryside. In this study, emission factors (Efs) for 13 PAH species and 21 NPAH species for four raw coal (three bituminous and one anthracite), one honeycomb briquette, and one crop residue pellet (peanut hulls) samples burned in a typical Chinese rural cooking stove were determined experimentally. The PAH and NPAH Efs for the six fuels were 3.15-49 mg/kg and 0.32-100 μg/kg, respectively. Peanut hulls had very high Efs for both PAHs and NPAHs, and honeycomb briquettes had the lowest Efs. 2-Nitropyrene and 2-nitrofluoranthene, which are NPAHs typically found in secondary organic aerosol, were detected in the emissions from some fuels, suggesting that chemical reactions may have occurred in the dilution tunnel between the flue gas leaving the stove and entering the sampler. The 1-nitropyrene to pyrene diagnostic ratios for coal and peanut hulls were 0.0001 ± 0.0001 and 0.0005, respectively. These were in the same order of magnitude as reference ratios for emissions during coal combustion. The 6-nitrobenzo[a]pyrene to benzo[a]pyrene ratios for the fuels were determined, and the ratios for coal and peanut hulls were 0.0010 ± 0.0001 and 0.0014, respectively. The calculated potential toxic risks indicated that peanut hull emissions were very toxic, especially in terms of NPAHs, compared with emissions from the other fuels. Copyright © 2017 Elsevier Ltd. All rights reserved.

Base Carbone. Documentation about the emission factors of the Base CarboneR database

International Nuclear Information System (INIS)

2014-01-01

The Base Carbone R is a public database of emission factors as required for carrying out carbon accounting exercises. It is administered by ADEME, but its governance involves many stakeholders and it can be added to freely. The articulation and convergence of environmental regulations requires data homogenization. The Base Carbone R proposes to be this centralized data source. Today, it is the reference database for article 75 of the Grenelle II Act. It is also entirely consistent with article L1341-3 of the French Transport Code and the default values of the European emission quotas exchange system. The data of the Base Carbone R can be freely consulted by all. Furthermore, the originality of this tool is that it enables third parties to propose their own data (feature scheduled for February 2015). These data are then assessed for their quality and transparency, then validated or refused for incorporation in the Base Carbone R . Lastly, a forum (planned for February 2015) will enable users to ask questions about the data, or to contest the data. The administration of the Base Carbone R is handled by ADEME. However, its orientation and the data that it contains are validated by a governance committee incorporating various public and private stakeholders. Lastly, transparency is one of the keystones of the Base Carbone R . Documentation details the hypotheses underlying the construction of all the data in the base, and refers to the studies that have enabled their construction. This document brings together the different versions of the Base Carbone R documentation: the most recent version (v11.5) and the previous versions (v11.0) which is shared in 2 parts dealing with the general case and with the specific case of overseas territories

On-road particulate emission measurement

Science.gov (United States)

Mazzoleni, Claudio

Particulate matter (PM) suspended in the atmosphere has harmful health effects, contributes to visibility impairment, and affects atmospheric radiative transfer, thereby contributing to global change. Vehicles contribute substantially to the ambient PM concentration in urban areas, yet the fraction of ambient PM originating from vehicle emissions is poorly characterized because suitable measurement methods have not been available. This dissertation describes the development and the use of a new vehicle emission remote sensing system (VERSS) for the on-road measurement of PM emission factors for vehicles. The PM VERSS measures PM by ultraviolet backscattering and transmission. PM backscattering and transmission mass efficiencies have been calculated from Mie theory based on an homogeneous spherical model for gasoline particles and on a two-layers, spherical model for diesel particles. The VERSS was used in a large-scale study in Las Vegas, NV. A commercial gaseous VERSS was used for the measurement of gaseous emission factors (i.e., carbon monoxide, hydrocarbons, and nitrogen oxide). Speed and acceleration were also measured for each vehicle. A video image of each vehicle's rear license plate was acquired and license plate numbers were matched with the Clark County department of motor vehicle database to retrieve vehicle information such as model year, vehicle weight category and engine ignition type. PM VERSS has precisely estimated PM fleet average emission factors and clearly shown the dependence of PM emission factors on vehicle model year. Under mostly hot-stabilized operation, diesel vehicle PM emission factors are about 25 times higher than those of gasoline vehicles. Furthermore, the fleet frequency distributions of PM emission factors are highly skewed, meaning that most of the fleet emission factor is accounted for by a small portion of the fleet. The PM VERSS can measure PM emission factors for these high emitting vehicles on an individual basis. PM

Factors Affecting Green Residential Building Development: Social Network Analysis

Directory of Open Access Journals (Sweden)

Xiaodong Yang

2018-05-01

Full Text Available Green residential buildings (GRBs are one of the effective practices of energy saving and emission reduction in the construction industry. However, many real estate developers in China are less willing to develop GRBs, because of the factors affecting green residential building development (GRBD. In order to promote the sustainable development of GRBs in China, this paper, based on the perspective of real estate developers, identifies the influential and critical factors affecting GRBD, using the method of social network analysis (SNA. Firstly, 14 factors affecting GRBD are determined from 64 preliminary factors of three main elements, and the framework is established. Secondly, the relationships between the 14 factors are analyzed by SNA. Finally, four critical factors for GRBD, which are on the local economy development level, development strategy and innovation orientation, developer’s acknowledgement and positioning for GRBD, and experience and ability for GRBD, are identified by the social network centrality test. The findings illustrate the key issues that affect the development of GRBs, and provide references for policy making by the government and strategy formulation by real estate developers.

The international research progress of Ammonia(NH3) emissions and emissions reduction technology in farmland ecosystem

Science.gov (United States)

Yang, W. Z.; Jiao, Y.

2017-03-01

NH3 is the important factor leading to the grey haze, and one of the main causes of environmental problems of serious ecological imbalance, such as acid rain and air quality deterioration. The fertilizer excessive application of the current farmland results NH3 emissions intensity greatly. In order to clear the farmland NH3 emissions research status and achievements, the literature of farmland NH3 emission related were retrievaled by the SCI journals and Chinese science citation database. Some factors of NH3 emission were analyzed such as soil factors, climate factors and farmland management measures. The research progress was inductived on farmland NH3 emission reduction technology. The results will help to clarify farmland NH3 emissions research progress. The theoretical guidance was provided on the future of farmland NH3 emissions research.

Factors affecting volume calculation with single photon emission tomography (SPECT) method

International Nuclear Information System (INIS)

Liu, T.H.; Lee, K.H.; Chen, D.C.P.; Ballard, S.; Siegel, M.E.

1985-01-01

Several factors may influence the calculation of absolute volumes (VL) from SPECT images. The effect of these factors must be established to optimize the technique. The authors investigated the following on the VL calculations: % of background (BG) subtraction, reconstruction filters, sample activity, angular sampling and edge detection methods. Transaxial images of a liver-trunk phantom filled with Tc-99m from 1 to 3 μCi/cc were obtained in 64x64 matrix with a Siemens Rota Camera and MDS computer. Different reconstruction filters including Hanning 20,32, 64 and Butterworth 20, 32 were used. Angular samplings were performed in 3 and 6 degree increments. ROI's were drawn manually and with an automatic edge detection program around the image after BG subtraction. VL's were calculated by multiplying the number of pixels within the ROI by the slice thickness and the x- and y- calibrations of each pixel. One or 2 pixel per slice thickness was applied in the calculation. An inverse correlation was found between the calculated VL and the % of BG subtraction (r=0.99 for 1,2,3 μCi/cc activity). Based on the authors' linear regression analysis, the correct liver VL was measured with about 53% BG subtraction. The reconstruction filters, slice thickness and angular sampling had only minor effects on the calculated phantom volumes. Detection of the ROI automatically by the computer was not as accurate as the manual method. The authors conclude that the % of BG subtraction appears to be the most important factor affecting the VL calculation. With good quality control and appropriate reconstruction factors, correct VL calculations can be achieved with SPECT

Emission factors of fine particulate matter, organic and elemental carbon, carbon monoxide, and carbon dioxide for four solid fuels commonly used in residential heating by the U.S. Navajo Nation.

Science.gov (United States)

Champion, Wyatt M; Connors, Lea; Montoya, Lupita D

2017-09-01

Most homes in the Navajo Nation use wood as their primary heating fuel, often in combination with locally mined coal. Previous studies observed health effects linked to this solid-fuel use in several Navajo communities. Emission factors (EFs) for common fuels used by the Navajo have not been reported using a relevant stove type. In this study, two softwoods (ponderosa pine and Utah juniper) and two high-volatile bituminous coals (Black Mesa and Fruitland) were tested with an in-use residential conventional wood stove (homestove) using a modified American Society for Testing and Materials/U.S. Environmental Protection Agency (ASTM/EPA) protocol. Filter sampling quantified PM 2.5 (particulate matter with an aerodynamic diameter ≤2.5 μm) and organic (OC) and elemental (EC) carbon in the emissions. Real-time monitoring quantified carbon monoxide (CO), carbon dioxide (CO 2 ), and total suspended particles (TSP). EFs for these air pollutants were developed and normalized to both fuel mass and energy consumed. In general, coal had significantly higher mass EFs than wood for all pollutants studied. In particular, coal emitted, on average, 10 times more PM 2.5 than wood on a mass basis, and 2.4 times more on an energy basis. The EFs developed here were based on fuel types, stove design, and operating protocols relevant to the Navajo Nation, but they could be useful to other Native Nations with similar practices, such as the nearby Hopi Nation. Indoor wood and coal combustion is an important contributor to public health burdens in the Navajo Nation. Currently, there exist no emission factors representative of Navajo homestoves, fuels, and practices. This study developed emission factors for PM 2.5 , OC, EC, CO, and CO 2 using a representative Navajo homestove. These emission factors may be utilized in regional-, national-, and global-scale health and environmental models. Additionally, the protocols developed and results presented here may inform on-going stove design of

Factors affecting construction performance: exploratory factor analysis

Science.gov (United States)

Soewin, E.; Chinda, T.

2018-04-01

The present work attempts to develop a multidimensional performance evaluation framework for a construction company by considering all relevant measures of performance. Based on the previous studies, this study hypothesizes nine key factors, with a total of 57 associated items. The hypothesized factors, with their associated items, are then used to develop questionnaire survey to gather data. The exploratory factor analysis (EFA) was applied to the collected data which gave rise 10 factors with 57 items affecting construction performance. The findings further reveal that the items constituting ten key performance factors (KPIs) namely; 1) Time, 2) Cost, 3) Quality, 4) Safety & Health, 5) Internal Stakeholder, 6) External Stakeholder, 7) Client Satisfaction, 8) Financial Performance, 9) Environment, and 10) Information, Technology & Innovation. The analysis helps to develop multi-dimensional performance evaluation framework for an effective measurement of the construction performance. The 10 key performance factors can be broadly categorized into economic aspect, social aspect, environmental aspect, and technology aspects. It is important to understand a multi-dimension performance evaluation framework by including all key factors affecting the construction performance of a company, so that the management level can effectively plan to implement an effective performance development plan to match with the mission and vision of the company.

Cooking with Fire: The Mutagenicity- and PAH-Emission ...

Science.gov (United States)

Emissions from solid fuels used for cooking cause ~4 million premature deaths per year. Advanced solid-fuel cookstoves are a potential solution, but they should be assessed by appropriate performance indicators, including biological effects. We evaluated two categories of solid-fuel cookstoves for 8 pollutant- and 4 mutagenicity-emission factors, correlated the mutagenicity-emission factors, and compared them to those of other combustion emissions. We burned red oak in a 3-stone fire (TSF), a natural-draft stove (NDS), and a forced-draft stove (FDS); we combusted propane as a liquified petroleum gas control fuel. We determined emission factors based on useful energy (megajoules delivered, MJd) for carbon monoxide, nitrogen oxides (NOx), black carbon, methane, total hydrocarbons, 32 polycyclic aromatic hydrocarbons, PM2.5, levoglucosan (a wood-smoke marker), and mutagenicity in Salmonella. Other than NOx the emission factors per MJd correlated highly among each other (r2 ≥ 0.92); NOx correlated 0.58-0.76 with the other emission factors. Excluding NOx, the NDS and FDS reduced the emission factors on average 68 and 92%, respectively, relative to the TSF. Nonetheless, the mutagenicity-emission factor based on fuel energy used (MJthermal) for the most efficient stove (FDS) was intermediate to that of a large diesel bus engine and a small diesel generator. Both mutagenicity- and pollutant-emission factors may be informative for characterizing cookstove

Activation of human factor V by factor Xa and thrombin

International Nuclear Information System (INIS)

Monkovic, D.D.; Tracy, P.B.

1990-01-01

The activation of human factor V by factor Xa and thrombin was studied by functional assessment of cofactor activity and sodium dodecyl sulfate-polycarylamide gel electrophoresis followed by either autoradiography of 125 I-labeled factor V activation products or Western blot analyses of unlabeled factor V activation products. Cofactor activity was measured by the ability of the factor V/Va peptides to support the activation of prothrombin. The factor Xa catalyzed cleavage of factor V was observed to be time, phospholipid, and calcium ion dependent, yielding a cofactor with activity equal to that of thrombin-activated factor V (factor Va). The cleavage pattern differed markedly from the one observed in the bovine system. The factor Xa activated factor V subunits expressing cofactor activity were isolated and found to consist of peptides of M r 220,000 and 105,000. Although thrombin cleaved the M r 220,000 peptide to yield peptides previously shown to be products of thrombin activation, cofactor activity did not increase. N-Terminal sequence analysis confirmed that both factor Xa and thrombin cleave factor V at the same bond to generate the M r 220,000 peptide. The factor Xa dependent functional assessment of 125 I-labeled factor V coupled with densitometric analyses of the cleavage products indicated that the cofactor activity of factor Xa activated factor V closely paralleled the appearance of the M r 220,000 peptide. The data indicate that factor Xa is as efficient an enzyme toward factor V as thrombin

Effects of endogenous factors on regional land-use carbon emissions based on the Grossman decomposition model: a case study of Zhejiang Province, China.

Science.gov (United States)

Wu, Cifang; Li, Guan; Yue, Wenze; Lu, Rucheng; Lu, Zhangwei; You, Heyuan

2015-02-01

The impact of land-use change on greenhouse gas emissions has become a core issue in current studies on global change and carbon cycle. However, a comprehensive evaluation of the effects of land-use changes on carbon emissions is very necessary. This paper attempted to apply the Grossman decomposition model to estimate the scale, structural, and management effects of land-use carbon emissions based on final energy consumption by establishing the relationship between the types of land use and carbon emissions in energy consumption. It was shown that land-use carbon emissions increase from 169.5624 million tons in 2000 to 637.0984 million tons in 2010, with an annual average growth rate of 14.15%. Meanwhile, land-use carbon intensity increased from 17.59 t/ha in 2000 to 64.42 t/ha in 2010, with an average annual growth rate of 13.86%. The results indicated that rapid industrialization and urbanization in Zhejiang Province promptly increased urban land and industrial land, which consequently affected land-use extensive emissions. The structural and management effects did not mitigate land-use carbon emissions. By contrast, both factors evidently affected the growth of carbon emissions because of the rigid demands of energy-intensive land-use types and the absence of land management. Results called for the policy implications of optimizing land-use structures and strengthening land-use management.

Effects of Endogenous Factors on Regional Land-Use Carbon Emissions Based on the Grossman Decomposition Model: A Case Study of Zhejiang Province, China

Science.gov (United States)

Wu, Cifang; Li, Guan; Yue, Wenze; Lu, Rucheng; Lu, Zhangwei; You, Heyuan

2015-02-01

The impact of land-use change on greenhouse gas emissions has become a core issue in current studies on global change and carbon cycle. However, a comprehensive evaluation of the effects of land-use changes on carbon emissions is very necessary. This paper attempted to apply the Grossman decomposition model to estimate the scale, structural, and management effects of land-use carbon emissions based on final energy consumption by establishing the relationship between the types of land use and carbon emissions in energy consumption. It was shown that land-use carbon emissions increase from 169.5624 million tons in 2000 to 637.0984 million tons in 2010, with an annual average growth rate of 14.15 %. Meanwhile, land-use carbon intensity increased from 17.59 t/ha in 2000 to 64.42 t/ha in 2010, with an average annual growth rate of 13.86 %. The results indicated that rapid industrialization and urbanization in Zhejiang Province promptly increased urban land and industrial land, which consequently affected land-use extensive emissions. The structural and management effects did not mitigate land-use carbon emissions. By contrast, both factors evidently affected the growth of carbon emissions because of the rigid demands of energy-intensive land-use types and the absence of land management. Results called for the policy implications of optimizing land-use structures and strengthening land-use management.

Impacts of biological and procedural factors on semiquantification uptake value of liver in fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography imaging.

Science.gov (United States)

Mahmud, Mohd Hafizi; Nordin, Abdul Jalil; Ahmad Saad, Fathinul Fikri; Azman, Ahmad Zaid Fattah

2015-10-01

Increased metabolic activity of fluorodeoxyglucose (FDG) in tissue is not only resulting of pathological uptake, but due to physiological uptake as well. This study aimed to determine the impacts of biological and procedural factors on FDG uptake of liver in whole body positron emission tomography/computed tomography (PET/CT) imaging. Whole body fluorine-18 ((18)F) FDG PET/CT scans of 51 oncology patients have been reviewed. Maximum standardized uptake value (SUVmax) of lesion-free liver was quantified in each patient. Pearson correlation was performed to determine the association between the factors of age, body mass index (BMI), blood glucose level, FDG dose and incubation period and liver SUVmax. Multivariate regression analysis was established to determine the significant factors that best predicted the liver SUVmax. Then the subjects were dichotomised into four BMI groups. Analysis of variance (ANOVA) was established for mean difference of SUVmax of liver between those BMI groups. BMI and incubation period were significantly associated with liver SUVmax. These factors were accounted for 29.6% of the liver SUVmax variance. Statistically significant differences were observed in the mean SUVmax of liver among those BMI groups (Pvalue for physiological liver SUVmax as a reference standard for different BMI of patients in PET/CT interpretation and use a standard protocol for incubation period of patient to reduce variation in physiological FDG uptake of liver in PET/CT study.

Emission factors and their uncertainty for the exchange of CO2, CH4 and N2O in Finnish managed peatlands

International Nuclear Information System (INIS)

Alm, J.; Shurpali, N. J.; Minkkinen, K.

2007-01-01

This paper summarises the results of several research groups participating in the research programme 'Greenhouse Impacts of the use of Peat and Peatlands in Finland', and presents emission factors for peat-atmosphere fluxes of CO 2 , CH 4 , and N 2 O, filling gaps in knowledge concerning the afforestation of organic croplands and cutaways, and improves the emission assessment of peatlands drained for forestry. Forest drainage may result in net binding of soil carbon or net release, depending on site characteristics and the tree stand. Use of peatlands for agriculture (48-4821 g CO 2 -eq. m -2 a -1 ), even after the cultivation has ceased, or for milled peat harvesting (1948-2478 g CO 2 -eq. m -2 a -1 ) can cause the highest overall emissions. Extremely high CO 2 emissions are possible from peat harvesting areas during wet and warm summers. Afforestation of those peatlands abandoned from cultivation or peat harvesting can reduce the warming impact at least during the first tree generation. Heterotrophic soil respiration may have a systematic south-north difference in temperature response. More data must be collected before the information on peatland forest soil CO 2 emissions can be adapted for different climatic regions in Finland. A test of the model DNDC against measured data showed that DNDC has to be developed further before it can be used in estimating N 2 O emissions from boreal peatlands. (orig.)

Velocity-dependent emission factors of benzene, toluene and C 2-benzenes of a passenger car equipped with and without a regulated 3-way catalyst

Science.gov (United States)

Heeb, Norbert V.; Forss, Anna-Maria; Bach, Christian; Mattrel, Peter

Time-resolved chemical ionization mass spectrometry (CI-MS) has been used to investigate the velocity-dependent emission factors for benzene, toluene, the C 2-benzenes (xylenes and ethyl benzene) and nitrogen monoxide of a gasoline-driven passenger car (1.4 l, model year 1995) driven with or without catalytic exhaust gas treatment. A set of seven different driving cycles - including the European Driving Cycle (EDC), the US Urban (FTP 75) and the Highway driving cycles - with a total driving time of 12,000 s have been studied. From the obtained emission data, two sets of 15,300 and 17,200 data points which represent transient driving in the velocity range of 0-150 km h -1 and in an acceleration window of -2-3 m s -2 were explored to gain velocity-dependent emission factors. The passenger car, equipped with a regulated rhodium-platinum based three-way catalyst, showed optimal conversion efficiency (>95%) for benzene in the velocity range of 60-120 km h -1. The conversion of benzene was reduced (speed and engine load (>130 km h -1). Whereas the conversion efficiency for the class of C 2-benzenes was reduced to 10%, no net conversion could be found for toluene and benzene when driven above 130 km h -1. In contrast, the benzene and toluene emissions exceeded those of the untreated exhaust gas in the velocity range of 130-150 km h -1 by 50-92% and by 10-34%, respectively. Thus, benzene and toluene were formed across the examined three-way catalyst if the engine is operated for an extended time in a fuel-rich mode (lambda<1).

Methanol emissions from maize: Ontogenetic dependence to varying light conditions and guttation as an additional factor constraining the flux

Science.gov (United States)

Mozaffar, A.; Schoon, N.; Digrado, A.; Bachy, A.; Delaplace, P.; du Jardin, P.; Fauconnier, M.-L.; Aubinet, M.; Heinesch, B.; Amelynck, C.

2017-03-01

Because of its high abundance and long lifetime compared to other volatile organic compounds in the atmosphere, methanol (CH3OH) plays an important role in atmospheric chemistry. Even though agricultural crops are believed to be a large source of methanol, emission inventories from those crop ecosystems are still scarce and little information is available concerning the driving mechanisms for methanol production and emission at different developmental stages of the plants/leaves. This study focuses on methanol emissions from Zea mays L. (maize), which is vastly cultivated throughout the world. Flux measurements have been performed on young plants, almost fully grown leaves and fully grown leaves, enclosed in dynamic flow-through enclosures in a temperature and light-controlled environmental chamber. Strong differences in the response of methanol emissions to variations in PPFD (Photosynthetic Photon Flux Density) were noticed between the young plants, almost fully grown and fully grown leaves. Moreover, young maize plants showed strong emission peaks following light/dark transitions, for which guttation can be put forward as a hypothetical pathway. Young plants' average daily methanol fluxes exceeded by a factor of 17 those of almost fully grown and fully grown leaves when expressed per leaf area. Absolute flux values were found to be smaller than those reported in the literature, but in fair agreement with recent ecosystem scale flux measurements above a maize field of the same variety as used in this study. The flux measurements in the current study were used to evaluate the dynamic biogenic volatile organic compound (BVOC) emission model of Niinemets and Reichstein. The modelled and measured fluxes from almost fully grown leaves were found to agree best when a temperature and light dependent methanol production function was applied. However, this production function turned out not to be suitable for modelling the observed emissions from the young plants

Characterization factors for terrestrial acidification at the global scale: a systematic analysis of spatial variability and uncertainty.

Science.gov (United States)

Roy, Pierre-Olivier; Azevedo, Ligia B; Margni, Manuele; van Zelm, Rosalie; Deschênes, Louise; Huijbregts, Mark A J

2014-12-01

Characterization factors (CFs) are used in life cycle assessment (LCA) to quantify the potential impact per unit of emission. CFs are obtained from a characterization model which assess the environmental mechanisms along the cause-effect chain linking an emission to its potential damage on a given area of protection, such as loss in ecosystem quality. Up to now, CFs for acidifying emissions did not cover the global scale and were only representative of their characterization model geographical scope. Consequently, current LCA practices implicitly assume that all emissions from a global supply chain occur within the continent referring to the characterization method geographical scope. This paper provides worldwide 2°×2.5° spatially-explicit CFs, representing the change in relative loss of terrestrial vascular plant species due to an emission change of nitrogen oxides (NOx), ammonia (NH3) and sulfur dioxide (SO2). We found that spatial variability in the CFs is much larger compared to statistical uncertainty (six orders of magnitude vs. two orders of magnitude). Spatial variability is mainly caused by the atmospheric fate factor and soil sensitivity factor, while the ecological effect factor is the dominant contributor to the statistical uncertainty. The CFs provided in our study allow the worldwide spatially explicit evaluation of life cycle impacts related to acidifying emissions. This opens the door to evaluate regional life cycle emissions of different products in a global economy. Copyright © 2014 Elsevier B.V. All rights reserved.

Factorization and non-factorization in diffractive hard scattering

International Nuclear Information System (INIS)

Berera, Arjun

1997-01-01

Factorization, in the sense defined for inclusive hard scattering, is discussed for diffractive hard scattering. A factorization theorem similar to its inclusive counterpart is presented for diffractive DIS. For hadron-hadron diffractive hard scattering, in contrast to its inclusive counterpart, the expected breakdown of factorization is discussed. Cross section estimates are given from a simple field theory model for non-factorizing double-pomeron-exchange (DPE) dijet production with and without account for Sudakov suppression

Exchange factor method: an alternative zonal formulation for analysis of radiating enclosures containing participating media

International Nuclear Information System (INIS)

Larsen, M.E.

1983-01-01

The exchange factor method (EFM) is introduced and compared to the zone method (ZM). In both the EFM and ZM the region of interest is discretized into volume and surface elements, each considered to be isothermal, which are small enough to give the required resolution. A suitable set of state variables for the system is composed of the surface element radiosities and the gas element emissive powers. The EFM defines exchange factors as dimensionless total-exchange areas for radiant interchange between volume and surface elements by all possible absorption/re-emission paths, but excluding wall reflections. In the EFM, the exchange factors replace the direct-exchange areas of the ZM and are used to write energy balances for each area and volume element in the system. As in the ZM, the radiant energy balance equations result in a set of algebraic equations linear in the system state variables. The distinguishing feature of the EFM is that exchange factors may be measurable quantities. Relationships between the EFM exchange factors and the ZM direct-exchange areas are presented. EFM conservation and reciprocity laws, analogous to those of the ZM, are also included. Temperature and heat flux distributions, predicted using the EFM, for two- and three-dimensional enclosures containing absorbing/emitting, isotropically scattering, and conducting media are included. An application of the EFM is proposed which calls for the measurement of exchange factors in a scale model of the enclosure to be analyzed. The measurement of these factors in an enclosure containing an isotropically scattering medium is discussed. The effects of isotropic scattering and absorption/re-emission processes are shown to be indistinguishable in their contribution to exchange factor paths

Risk and contributing factors of ecosystem shifts over naturally vegetated land under climate change in China.

Science.gov (United States)

Yin, Yuanyuan; Tang, Qiuhong; Wang, Lixin; Liu, Xingcai

2016-02-12

Identifying the areas at risk of ecosystem transformation and the main contributing factors to the risk is essential to assist ecological adaptation to climate change. We assessed the risk of ecosystem shifts in China using the projections of four global gridded vegetation models (GGVMs) and an aggregate metric. The results show that half of naturally vegetated land surface could be under moderate or severe risk at the end of the 21(st) century under the middle and high emission scenarios. The areas with high risk are the Tibetan Plateau region and an area extended northeastward from the Tibetan Plateau to northeast China. With the three major factors considered, the change in carbon stocks is the main contributing factor to the high risk of ecosystem shifts. The change in carbon fluxes is another important contributing factor under the high emission scenario. The change in water fluxes is a less dominant factor except for the Tibetan Plateau region under the high emission scenario. Although there is considerable uncertainty in the risk assessment, the geographic patterns of the risk are generally consistent across different scenarios. The results could help develop regional strategies for ecosystem conservation to cope with climate change.

Elemental composition of current automotive braking materials and derived air emission factors

NARCIS (Netherlands)

Hulskotte, J.H.J.; Roskam, G.D.; Denier van der Gon, H.A.C.

2014-01-01

Wear-related PM emissions are an important constituent of total PM emissions from road transport. Due to ongoing (further) exhaust emission reduction wear emissions may become the dominant PM source from road transport in the near future. The chemical composition of the wear emissions is crucial

Factors controlling peat chemistry and vegetation composition in Sudbury peatlands after 30 years of pollution emission reductions

International Nuclear Information System (INIS)

Barrett, Sophie E.; Watmough, Shaun A.

2015-01-01

The objective of this research was to assess factors controlling peat and plant chemistry, and vegetation composition in 18 peatlands surrounding Sudbury after more than 30 years of large (>95%) pollution emission reductions. Sites closer to the main Copper Cliff smelter had more humified peat and the surface horizons were greatly enriched in copper (Cu) and nickel (Ni). Copper and Ni concentrations in peat were significantly correlated with that in the plant tissue of Chamaedaphne calyculata. The pH of peat was the strongest determining factor for species richness, diversity, and community composition, although percent vascular plant cover was strongly negatively correlated with surface Cu and Ni concentrations in peat. Sphagnum frequency was also negatively related to peat Cu and Ni concentrations indicating sites close to Copper Cliff smelter remain adversely impacted by industrial activities. - Highlights: • Surface peat in wetlands in Sudbury is contaminated with Cu and Ni. • The pH of peat is positively related to species richness and diversity. • Metal levels in peat is negatively related to vascular vegetation and Sphagnum cover. • Loss of Sphagnum at contaminated peatlands may impede recovery. - Sudbury peatlands remain impacted by industrial activities as indicated by elevated copper and nickel concentrations and diminished vascular plant cover and Sphagnum frequency.

Brown carbon aerosols from burning of boreal peatlands: microphysical properties, emission factors, and implications for direct radiative forcing

Directory of Open Access Journals (Sweden)

R. K. Chakrabarty

2016-03-01

Full Text Available The surface air warming over the Arctic has been almost twice as much as the global average in recent decades. In this region, unprecedented amounts of smoldering peat fires have been identified as a major emission source of climate-warming agents. While much is known about greenhouse gas emissions from these fires, there is a knowledge gap on the nature of particulate emissions and their potential role in atmospheric warming. Here, we show that aerosols emitted from burning of Alaskan and Siberian peatlands are predominantly brown carbon (BrC – a class of visible light-absorbing organic carbon (OC – with a negligible amount of black carbon content. The mean fuel-based emission factors for OC aerosols ranged from 3.8 to 16.6 g kg−1. Their mass absorption efficiencies were in the range of 0.2–0.8 m2 g−1 at 405 nm (violet and dropped sharply to 0.03–0.07 m2 g−1 at 532 nm (green, characterized by a mean Ångström exponent of  ≈  9. Electron microscopy images of the particles revealed their morphologies to be either single sphere or agglomerated “tar balls”. The shortwave top-of-atmosphere aerosol radiative forcing per unit optical depth under clear-sky conditions was estimated as a function of surface albedo. Only over bright surfaces with albedo greater than 0.6, such as snow cover and low-level clouds, the emitted aerosols could result in a net warming (positive forcing of the atmosphere.

Crystal Structure of Human Factor VIII: Implications for the Formation of the Factor IXa-Factor VIIIa Complex

Energy Technology Data Exchange (ETDEWEB)

Ngo, J.C.; Huang, M.; Roth, D.A.; Furie, B.C.; Furie, B. (Wyeth); (MBL)

2008-06-03

Factor VIII is a procofactor that plays a critical role in blood coagulation, and is missing or defective in hemophilia A. We determined the X-ray crystal structure of B domain-deleted human factor VIII. This protein is composed of five globular domains and contains one Ca{sup 2+} and two Cu{sup 2+} ions. The three homologous A domains form a triangular heterotrimer where the A1 and A3 domains serve as the base and interact with the C2 and C1 domains, respectively. The structurally homologous C1 and C2 domains reveal membrane binding features. Based on biochemical studies, a model of the factor IXa-factor VIIIa complex was constructed by in silico docking. Factor IXa wraps across the side of factor VIII, and an extended interface spans the factor VIII heavy and light chains. This model provides insight into the activation of factor VIII and the interaction of factor VIIIa with factor IXa on the membrane surface.

Crystal Structure of Human Factor VIII: Implications for the Formation of the Factor IXa-Factor VIIIa Complex

Energy Technology Data Exchange (ETDEWEB)

Chi Ki Ngo,J.; Huang, M.; Roth, D.; Furie, B.; Furie, B.

2008-01-01

Factor VIII is a procofactor that plays a critical role in blood coagulation, and is missing or defective in hemophilia A. We determined the X-ray crystal structure of B domain-deleted human factor VIII. This protein is composed of five globular domains and contains one Ca(2+) and two Cu(2+) ions. The three homologous A domains form a triangular heterotrimer where the A1 and A3 domains serve as the base and interact with the C2 and C1 domains, respectively. The structurally homologous C1 and C2 domains reveal membrane binding features. Based on biochemical studies, a model of the factor IXa-factor VIIIa complex was constructed by in silico docking. Factor IXa wraps across the side of factor VIII, and an extended interface spans the factor VIII heavy and light chains. This model provides insight into the activation of factor VIII and the interaction of factor VIIIa with factor IXa on the membrane surface.

Activation of factor VII bound to tissue factor: A key early step in the tissue factor pathway of blood coagulation

International Nuclear Information System (INIS)

Rao, L.V.M.; Rapaport, S.I.

1988-01-01

Whether the factor VII/tissue factor complex that forms in tissue factor-dependent blood coagulation must be activated to factor VIIa/tissue factor before it can activate its substrates, factor X and IX, has been a difficult question to answer because the substrates, once activated, back-activate factor VII. The earlier studies suggested that human factor VII/tissue factor cannot activate factor IX. Studies have now been extended to the activation of factor X. Reaction mixtures were made with purified factor VII, X, and tissue factor; in some experiments antithrombin III and heparin were added to prevent back-activation of factor VII. Factor X was activated at similar rates in reaction mixtures containing either VII or factor VIIa after an initial 30-sec lag with factor VII. In reaction mixtures with factor VII a linear activation of factor X was established several minutes before cleavage of 125 I-labeled factor VII to the two-chain activated molecule was demonstrable on gel profiles. These data suggest that factor VII/tissue factor cannot activate measurable amounts of factor X over several minutes. Overall, the results support the hypothesis that a rapid preferential activation of factor VII bound to tissue factor by trace amounts of factor Xa is a key early step in tissue factor-dependent blood coagulation

Modeling Indicator Systems for Evaluating Environmental Sustainable Development Based on Factor Analysis

Institute of Scientific and Technical Information of China (English)

WU Hao; CHEN Xiaoling; HE Ying; HE Xiaorong; CAI Xiaobin; XU Keyan

2006-01-01

Indicator systems of environmental sustainable development in the Poyang Lake Basin are established from 51 elementary indexes by factor analysis, which is composed of four steps such as the factor model, the parameter estimation, the factor rotation and the factor score. Under the condition that the cumulative proportion is greater than 85%, 5 explicit factors of environmental sustainable development as well as its factor score by region are carried out. The result indicates some impact factors to the basin environmental in descending sort order are volume of water, volume of waste gas discharge, volume of solid wastes, the degree to comprehensive utilization of waste gas, waste water and solid wastes, the emission volume of waste gas, waste water and solid wastes. It is helpful and important to provide decision support for constituting sustainable development strategies and evaluate the sustainable development status of each city.

Characterization factors for global warming in life cycle assessment based on damages to humans and ecosystems.

Science.gov (United States)

De Schryver, An M; Brakkee, Karin W; Goedkoop, Mark J; Huijbregts, Mark A J

2009-03-15

Human and ecosystem health damage due to greenhouse gas (GHG) emissions is generally poorly quantified in the life cycle assessment of products, preventing an integrated comparison of the importance of GHGs with other stressor types, such as ozone depletion and acidifying emissions. In this study, we derived new characterization factors for 63 GHGs that quantify the impact of an emission change on human and ecosystem health damage. For human health damage, the Disability Adjusted Life Years (DALYs) per unit emission related to malaria, diarrhea, malnutrition, drowning, and cardiovascular diseases were quantified. For ecosystem health damage, the Potentially Disappeared Fraction (PDF) over space and time of various species groups, including plants, butterflies, birds, and mammals, per unit emission was calculated. The influence of value choices in the modeling procedure was analyzed by defining three coherent scenarios, based on Cultural theory perspectives. It was found that the characterization factor for human health damage by carbon dioxide (CO2) ranges from 1.1 x 10(-2) to 1.8 x 10(+1) DALY per kton of emission, while the characterization factor for ecosystem damage by CO2 ranges from 5.4 x 10(-2) to 1.2 x 10(+1) disappeared fraction of species over space and time ((km2 x year)/kton), depending on the scenario chosen. The characterization factor of a GHG can change up to 4 orders of magnitude, depending on the scenario. The scenario-specific differences are mainly explained by the choice for a specific time horizon and stresses the importance of dealing with value choices in the life cycle impact assessment of GHG emissions.

Factorization of standard model cross sections at ultrahigh energy

Science.gov (United States)

Chien, Yang-Ting; Li, Hsiang-nan

2018-03-01

The factorization theorem for organizing multiple electroweak boson emissions at future colliders with energy far above the electroweak scale is formulated. Taking the inclusive muon-pair production in electron-positron collisions as an example, we argue that the summation over isospins is demanded for constructing the universal distributions of leptons and gauge bosons in an electron. These parton distributions are shown to have the same infrared structure in the phases of broken and unbroken electroweak symmetry, an observation consistent with the Goldstone equivalence theorem. The electroweak factorization of processes involving protons is sketched, with an emphasis on the subtlety of the scalar distributions. This formalism, in which electroweak shower effects are handled from the viewpoint of factorization theorem for the first time, is an adequate framework for collider physics at ultra high energy.

Activation of factor VII bound to tissue factor: a key early step in the tissue factor pathway of blood coagulation.

OpenAIRE

Rao, L V; Rapaport, S I

1988-01-01

Whether the factor VII/tissue factor complex that forms in tissue factor-dependent blood coagulation must be activated to factor VIIa/tissue factor before it can activate its substrates, factor X and factor IX, has been a difficult question to answer because the substrates, once activated, back-activate factor VII. Our earlier studies suggested that human factor VII/tissue factor cannot activate factor IX. Studies have now been extended to the activation of factor X. Reaction mixtures were ma...

Risk Factors

Science.gov (United States)

... cells do not invade nearby tissues or spread. Risk Factors Key Points Factors That are Known to ... chemicals . Factors That are Known to Increase the Risk of Cancer Cigarette Smoking and Tobacco Use Tobacco ...

Indoor inhalation intake fractions of fine particulate matter: Review of influencing factors

DEFF Research Database (Denmark)

Hodas, Natasha; Loh, Miranda; Shin, Hyeong-Moo

2016-01-01

Exposure to fine particulate matter (PM2.5) is a major contributor to the global human disease burden. The indoor environment is of particular importance when considering the health effects associated with PM2.5 exposures because people spend the majority of their time indoors and PM2.5 exposures...... per unit mass emitted indoors are two to three orders of magnitude larger than exposures to outdoor emissions. Variability in indoor PM2.5 intake fraction (iFin,total), which is defined as the integrated cumulative intake of PM2.5 per unit of emission, is driven by a combination of building......-specific, human-specific, and pollutant-specific factors. Due to a limited availability of data characterizing these factors, however, indoor emissions and intake of PM2.5 are not commonly considered when evaluating the environmental performance of product life cycles. With the aim of addressing this barrier...

Determining the Number of Factors in P-Technique Factor Analysis

Science.gov (United States)

Lo, Lawrence L.; Molenaar, Peter C. M.; Rovine, Michael

2017-01-01

Determining the number of factors is a critical first step in exploratory factor analysis. Although various criteria and methods for determining the number of factors have been evaluated in the usual between-subjects R-technique factor analysis, there is still question of how these methods perform in within-subjects P-technique factor analysis. A…

Endogenous electromagnetic forces emissions during cell respiration as additional factor in cancer origin.

Science.gov (United States)

Embi, Abraham A

2016-01-01

Seven decades ago, a seminal paper by Dr. Denham Harman in (J Gerontol 11(3):298-300, 1956), introduced a theory stating that there are good reasons for assuming that endogenous irradiation in the living cells could lead to cancer via an obscure mechanism. The main purpose of this manuscript is to shed some light in said mechanism by proposing a five-step eukaryotic cell cancer triggering cycle. In other words, a new factor is introduced, namely the recently found emissions of electromagnetic forces (EMFs) as a possible causing agent in diseases, including cancer. Introduced is an eukaryotic cell cancer inducing cycle. It includes five sequential steps of endogenous biological process that are backed by published scientific reports. It is a known fact that in order to achieve homeostasis, toxic reactive oxygen species (ROS) i.e. H2O2 molecules are broken down by the protein enzyme catalase. During this reaction EMFs are generated (Embi in AIS Physics 2(3):226-230, 2016). The EMFs recording breakthrough was possible due to the introduction of a novel table top microscopy technique to detect EMFs by using Prussian Blue Stain and nano-sized iron particles. There are different roots in molecular and clinical biology through which DNA damage could be programmed, EMFs emitted (during cell respiration) are herein proposed as an additional cause.

Heparanase enhances the generation of activated factor X in the presence of tissue factor and activated factor VII.

Science.gov (United States)

Nadir, Yona; Brenner, Benjamin; Fux, Liat; Shafat, Itay; Attias, Judith; Vlodavsky, Israel

2010-11-01

Heparanase is an endo-β-D-glucuronidase dominantly involved in tumor metastasis and angiogenesis. Recently, we demonstrated that heparanase is involved in the regulation of the hemostatic system. Our hypothesis was that heparanase is directly involved in activation of the coagulation cascade. Activated factor X and thrombin were studied using chromogenic assays, immunoblotting and thromboelastography. Heparanase levels were measured by enzyme-linked immunosorbent assay. A potential direct interaction between tissue factor and heparanase was studied by co-immunoprecipitation and far-western assays. Interestingly, addition of heparanase to tissue factor and activated factor VII resulted in a 3- to 4-fold increase in activation of the coagulation cascade as shown by increased activated factor X and thrombin production. Culture medium of human embryonic kidney 293 cells over-expressing heparanase and its derivatives increased activated factor X levels in a non-enzymatic manner. When heparanase was added to pooled normal plasma, a 7- to 8-fold increase in activated factor X level was observed. Subsequently, we searched for clinical data supporting this newly identified role of heparanase. Plasma samples from 35 patients with acute leukemia at presentation and 20 healthy donors were studied for heparanase and activated factor X levels. A strong positive correlation was found between plasma heparanase and activated factor X levels (r=0.735, P=0.001). Unfractionated heparin and an inhibitor of activated factor X abolished the effect of heparanase, while tissue factor pathway inhibitor and tissue factor pathway inhibitor-2 only attenuated the procoagulant effect. Using co-immunoprecipitation and far-western analyses it was shown that heparanase interacts directly with tissue factor. Overall, our results support the notion that heparanase is a potential modulator of blood hemostasis, and suggest a novel mechanism by which heparanase increases the generation of activated

Non-methane organic gas emissions from biomass burning: identification, quantification, and emission factors from PTR-ToF during the FIREX 2016 laboratory experiment

Science.gov (United States)

Koss, Abigail R.; Sekimoto, Kanako; Gilman, Jessica B.; Selimovic, Vanessa; Coggon, Matthew M.; Zarzana, Kyle J.; Yuan, Bin; Lerner, Brian M.; Brown, Steven S.; Jimenez, Jose L.; Krechmer, Jordan; Roberts, James M.; Warneke, Carsten; Yokelson, Robert J.; de Gouw, Joost

2018-03-01

Volatile and intermediate-volatility non-methane organic gases (NMOGs) released from biomass burning were measured during laboratory-simulated wildfires by proton-transfer-reaction time-of-flight mass spectrometry (PTR-ToF). We identified NMOG contributors to more than 150 PTR ion masses using gas chromatography (GC) pre-separation with electron ionization, H3O+ chemical ionization, and NO+ chemical ionization, an extensive literature review, and time series correlation, providing higher certainty for ion identifications than has been previously available. Our interpretation of the PTR-ToF mass spectrum accounts for nearly 90 % of NMOG mass detected by PTR-ToF across all fuel types. The relative contributions of different NMOGs to individual exact ion masses are mostly similar across many fires and fuel types. The PTR-ToF measurements are compared to corresponding measurements from open-path Fourier transform infrared spectroscopy (OP-FTIR), broadband cavity-enhanced spectroscopy (ACES), and iodide ion chemical ionization mass spectrometry (I- CIMS) where possible. The majority of comparisons have slopes near 1 and values of the linear correlation coefficient, R2, of > 0.8, including compounds that are not frequently reported by PTR-MS such as ammonia, hydrogen cyanide (HCN), nitrous acid (HONO), and propene. The exceptions include methylglyoxal and compounds that are known to be difficult to measure with one or more of the deployed instruments. The fire-integrated emission ratios to CO and emission factors of NMOGs from 18 fuel types are provided. Finally, we provide an overview of the chemical characteristics of detected species. Non-aromatic oxygenated compounds are the most abundant. Furans and aromatics, while less abundant, comprise a large portion of the OH reactivity. The OH reactivity, its major contributors, and the volatility distribution of emissions can change considerably over the course of a fire.

Non-methane organic gas emissions from biomass burning: identification, quantification, and emission factors from PTR-ToF during the FIREX 2016 laboratory experiment

Directory of Open Access Journals (Sweden)

A. R. Koss

2018-03-01

Full Text Available Volatile and intermediate-volatility non-methane organic gases (NMOGs released from biomass burning were measured during laboratory-simulated wildfires by proton-transfer-reaction time-of-flight mass spectrometry (PTR-ToF. We identified NMOG contributors to more than 150 PTR ion masses using gas chromatography (GC pre-separation with electron ionization, H3O+ chemical ionization, and NO+ chemical ionization, an extensive literature review, and time series correlation, providing higher certainty for ion identifications than has been previously available. Our interpretation of the PTR-ToF mass spectrum accounts for nearly 90 % of NMOG mass detected by PTR-ToF across all fuel types. The relative contributions of different NMOGs to individual exact ion masses are mostly similar across many fires and fuel types. The PTR-ToF measurements are compared to corresponding measurements from open-path Fourier transform infrared spectroscopy (OP-FTIR, broadband cavity-enhanced spectroscopy (ACES, and iodide ion chemical ionization mass spectrometry (I− CIMS where possible. The majority of comparisons have slopes near 1 and values of the linear correlation coefficient, R2, of  >  0.8, including compounds that are not frequently reported by PTR-MS such as ammonia, hydrogen cyanide (HCN, nitrous acid (HONO, and propene. The exceptions include methylglyoxal and compounds that are known to be difficult to measure with one or more of the deployed instruments. The fire-integrated emission ratios to CO and emission factors of NMOGs from 18 fuel types are provided. Finally, we provide an overview of the chemical characteristics of detected species. Non-aromatic oxygenated compounds are the most abundant. Furans and aromatics, while less abundant, comprise a large portion of the OH reactivity. The OH reactivity, its major contributors, and the volatility distribution of emissions can change considerably over the course of a fire.

An integrated analytical framework for quantifying the LCOE of waste-to-energy facilities for a range of greenhouse gas emissions policy and technical factors

International Nuclear Information System (INIS)

Townsend, Aaron K.; Webber, Michael E.

2012-01-01

This study presents a novel integrated method for considering the economics of waste-to-energy (WTE) facilities with priced greenhouse gas (GHG) emissions based upon technical and economic characteristics of the WTE facility, MSW stream, landfill alternative, and GHG emissions policy. The study demonstrates use of the formulation for six different policy scenarios and explores sensitivity of the results to ranges of certain technical parameters as found in existing literature. The study shows that details of the GHG emissions regulations have large impact on the levelized cost of energy (LCOE) of WTE and that GHG regulations can either increase or decrease the LCOE of WTE depending on policy choices regarding biogenic fractions from combusted waste and emissions from landfills. Important policy considerations are the fraction of the carbon emissions that are priced (i.e. all emissions versus only non-biogenic emissions), whether emissions credits are allowed due to reducing fugitive landfill gas emissions, whether biogenic carbon sequestration in landfills is credited against landfill emissions, and the effectiveness of the landfill gas recovery system where waste would otherwise have been buried. The default landfill gas recovery system effectiveness assumed by much of the industry yields GHG offsets that are very close to the direct non-biogenic GHG emissions from a WTE facility, meaning that small changes in the recovery effectiveness cause relatively larger changes in the emissions factor of the WTE facility. Finally, the economics of WTE are dependent on the MSW stream composition, with paper and wood being advantageous, metal and glass being disadvantageous, and plastics, food, and yard waste being either advantageous or disadvantageous depending upon the avoided tipping fee and the GHG emissions price.

Factors affecting metal and radionuclide pollution in the Baltic sea

Directory of Open Access Journals (Sweden)

Martin Lodenius

2016-12-01

Full Text Available External pollution load in the Baltic Sea originates from urban, agricultural and industrial sources. Emissions of heavy metals have decreased substantially in the catchment area but the temporal trends are not always significant and differ with sample, area and pollutant. The most significant source of anthropogenic radioactivity in the Baltic Sea is fallout from the Chernobyl accident in 1986. Many factors affect the future development of pollutant concentrations including anthropogenic emissions, political decisions and changes in salinity, temperature and water currents, in eutrophication and oxygen status, in fisheries and in atmospheric deposition of pollutants. Large scale changes like eutrophication and climate change affect ecosystems in many ways, directly and indirectly, causing biological and abiotic effects. These factors are interrelated and difficult to predict. Measures aiming to enhance the ecological status of the Baltic Sea will certainly give positive results but this will take at least several decades.

Transforming growth factor alpha, Shope fibroma growth factor, and vaccinia growth factor can replace myxoma growth factor in the induction of myxomatosis in rabbits.

Science.gov (United States)

Opgenorth, A; Nation, N; Graham, K; McFadden, G

1993-02-01

The epidermal growth factor (EGF) homologues encoded by vaccinia virus, myxoma virus, and malignant rabbit fibroma virus have been shown to contribute to the pathogenicity of virus infection upon inoculation of susceptible hosts. However, since the primary structures of these growth factors and the disease profiles induced by different poxvirus genera vary substantially, the degree to which the various EGF homologues perform similar roles in viral pathogenesis remains unclear. In order to determine whether different EGF-like growth factors can perform qualitatively similar functions in the induction of myxomatosis in rabbits, we created recombinant myxoma virus variants in which the native growth factor, myxoma growth factor (MGF), was disrupted and replaced with either vaccinia virus growth factor, Shope fibroma growth factor, or rat transforming growth factor alpha. Unlike the control virus containing an inactivated MGF gene, which caused marked attenuation of the disease syndrome and substantially less proliferation of the epithelial cell layers in the conjunctiva and respiratory tract, the recombinant myxoma virus strains expressing heterologous growth factors produced infections which were both clinically and histopathologically indistinguishable from wild-type myxomatosis. We conclude that these poxviral and cellular EGF-like growth factors, which are diverse with respect to primary structure and origin, have similar biological functions in the context of myxoma virus pathogenesis and are mitogenic for the same target cells.

Contact Us About Clearinghouse for Inventories and Emissions Factors

Science.gov (United States)

Emissions inventories, modeling, and monitoring are the basis for understanding, controlling and tracking stationary sources of air pollution. This technical site provides access to tools and data to support those efforts.

Chemical elements in pearl oysters (Paxyodon ponderosus), phytoplankton and estuarine sediments from eastern Amazon (Northern Brazil): Bioaccumulation factors and trophic transfer factors

Science.gov (United States)

Vilhena, Maria P. S. P.; Costa, Marcondes L.; Berrêdo, José F.; Paiva, Rosildo S.; Souza, Crisvaldo C. S.

2016-04-01

The current study was conducted near Barcarena County, which is a mid-sized urban center where aluminum ore processing industries (bauxite) and Vila do Conde cargo terminal are located. It aims to discuss the bioaccumulation factors as well as factors related to the trophic transfer of chemical elements in water, oyster, phytoplankton and bottom sediments from an estuary in the Brazilian Northern coast. The bioaccumulation factor (BAF), trophic transfer factor (TTF) and biota-sediment-water were used to correlate the contents of chemical elements found in organisms. The sediment, surface water, phytoplankton and pearl oysters chemical composition was analyzed by ICP-OES and ICP-MS. Pearl oysters showed K, Ca, Mg, P, Mn, Fe, Zn, Al, Ba and Pb accumulation, which concentration increase is associated with their diet (phytoplankton). Al concentrations are 14 times higher in pearl oysters (Paxyodon ponderosus), assuming that they are associated with wastewater emissions and with industrialization processes in the area. BAF and BSAF values are 1000 times higher than the metal concentrations in water and bioavailable fraction concentrations. The oyster-phytoplankton trophic transfer factor indicates that P, Ba, Ca, Na, Cd and Zn showed the largest transfers (from 5 to 19). These trophic transfers may be sufficient to cause significant ecotoxicological effects on the region biota.

Chinese life cycle impact assessment factors.

Science.gov (United States)

Yang, J X; Nielsen, P H

2001-04-01

The methodological basis and procedures for determination of Chinese normalization references and weighting factors according to the EDIP-method is described. According to Chinese industrial development intensity and population density, China was divided into three regions and the normalization references for each region were calculated on the basis of an inventory of all of the region's environmental emissions in 1990. The normalization reference was determined as the total environmental impact potential for the area in question in 1990 (EP(j)90) divided by the population. The weighting factor was determined as the normalization reference (ER(j)90) divided by society's target contribution in the year 2000 based on Chinese political reduction plans, ER(j)T2000. This paper presents and discuss results obtained for eight different environmental impact categories relevant for China: global warming, stratospheric ozone depletion, acidification, nutrient enrichment, photochemical ozone formation and generation of bulk waste, hazardous waste and slag and ashes.

Evaluating the Bulk Lorentz Factors of Outflow Material: Lessons Learned from the Extremely Energetic Outburst GRB 160625B

Energy Technology Data Exchange (ETDEWEB)

Wang, Yuan-Zhu; Wang, Hao; Zhang, Shuai; Liang, Yun-Feng; Jin, Zhi-Ping; He, Hao-Ning; Liao, Neng-Hui; Fan, Yi-Zhong; Wei, Da-Ming, E-mail: liangyf@pmo.ac.cn, E-mail: jin@pmo.ac.cn, E-mail: dmwei@pmo.ac.cn [Key Laboratory of Dark Matter and Space Astronomy, Purple Mountain Observatory, Chinese Academy of Science, Nanjing, 210008 (China)

2017-02-10

GRB 160625B is an extremely bright outburst with well-monitored afterglow emission. The geometry-corrected energy is high, up to ∼5.2 × 10{sup 52} erg or even ∼8 × 10{sup 52} erg, rendering it the most energetic GRB prompt emission recorded so far. We analyzed the time-resolved spectra of the prompt emission and found that in some intervals there were likely thermal-radiation components and the high energy emission was characterized by significant cutoff. The bulk Lorentz factors of the outflow material are estimated accordingly. We found out that the Lorentz factors derived in the thermal-radiation model are consistent with the luminosity-Lorentz factor correlation found in other bursts, as well as in GRB 090902B for the time-resolved thermal-radiation components, while the spectral cutoff model yields much lower Lorentz factors that are in tension with the constraints set by the electron pair Compton scattering process. We then suggest that these spectral cutoffs are more likely related to the particle acceleration process and that one should be careful in estimating the Lorentz factors if the spectrum cuts at a rather low energy (e.g., ∼tens of MeV). The nature of the central engine has also been discussed, and a stellar-mass black hole is favored.

Capacity factor of wind power realized values vs. estimates

International Nuclear Information System (INIS)

Boccard, Nicolas

2009-01-01

For two decades now, the capacity factor of wind power measuring the average energy delivered has been assumed in the 30-35% range of the name plate capacity. Yet, the mean realized value for Europe over the last five years is below 21%; accordingly private cost is two-third higher and the reduction of carbon emissions is 40% less than previously expected. We document this discrepancy and offer rationalizations that emphasize the long term variations of wind speeds, the behavior of the wind power industry, political interference and the mode of finance. We conclude with the consequences of the capacity factor miscalculation and some policy recommendations.

Factor concentrates for the treatment of factor XIII deficiency.

Science.gov (United States)

Gootenberg, J E

1998-11-01

Factor XIII deficiency is a severe autosomal recessive bleeding disorder associated with a characteristic pattern of neonatal hemorrhage and a lifelong bleeding diathesis. Even relatively minor trauma can be followed by prolonged and recurrent bleeding. Intracranial hemorrhage is a frequent complication. With the development of safe and effective factor XIII concentrates, reliable prophylactic treatment is possible. Two plasma-derived, virus-inactivated factor XIII concentrates are currently in production. The first, Fibrogammin P, (Centeon LLC, King of Prussia, PA, USA; and Centeon Pharma GmbH, Marburg, Germany) is marketed in Europe, South America, South Africa, and Japan. It is distributed in the United States under a Food and Drug Administration Investigational New Drug Application. A second factor XIII concentrate (Bio Products Laboratory, Elstree, UK) is available for use only on a "named patient" compassionate basis in the United Kingdom. Patients with factor XIII deficiency who receive appropriately timed periodic infusions of such factor XIII concentrates are able to live normal lives, free from catastrophic bleeding episodes.

Epidermal growth factor and insulin-like growth factor I upregulate the expression of the epidermal growth factor system in rat liver

DEFF Research Database (Denmark)

Bor, M V; Sørensen, B S; Vinter-Jensen, L

2000-01-01

BACKGROUND/AIM: Both epidermal growth factor and insulin-like growth factor I play a role in connection with the liver. In the present study, the possible interaction of these two growth factor systems was studied by investigating the effect of epidermal growth factor or insulin-like growth factor...... I treatment on the expression of the epidermal growth factor receptor, and its activating ligands, transforming growth factor-alpha and epidermal growth factor. METHODS: Fifty-five male rats received no treatment, human recombinant epidermal growth factor or human recombinant insulin-like growth.......8+/-1.6 fmol/mg protein epidermal growth factor and 144+/-22 fmol/mg protein transforming growth factor-alpha. Both epidermal growth factor and insulin-like growth factor I treatment increased the expression of mRNA for transforming growth factor-alpha and epidermal growth factor receptor, as well...

40 CFR 1039.245 - How do I determine deterioration factors from exhaust durability testing?

Science.gov (United States)

2010-07-01

... PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW AND IN-USE NONROAD... CFR 89.112 are considered to rely on established technology for gaseous emission control, except that... factors for an engine family with established technology based on engineering analysis instead of testing...

Uncertainty in projected climate change arising from uncertain fossil-fuel emission factors

Science.gov (United States)

Quilcaille, Y.; Gasser, T.; Ciais, P.; Lecocq, F.; Janssens-Maenhout, G.; Mohr, S.

2018-04-01

Emission inventories are widely used by the climate community, but their uncertainties are rarely accounted for. In this study, we evaluate the uncertainty in projected climate change induced by uncertainties in fossil-fuel emissions, accounting for non-CO2 species co-emitted with the combustion of fossil-fuels and their use in industrial processes. Using consistent historical reconstructions and three contrasted future projections of fossil-fuel extraction from Mohr et al we calculate CO2 emissions and their uncertainties stemming from estimates of fuel carbon content, net calorific value and oxidation fraction. Our historical reconstructions of fossil-fuel CO2 emissions are consistent with other inventories in terms of average and range. The uncertainties sum up to a ±15% relative uncertainty in cumulative CO2 emissions by 2300. Uncertainties in the emissions of non-CO2 species associated with the use of fossil fuels are estimated using co-emission ratios varying with time. Using these inputs, we use the compact Earth system model OSCAR v2.2 and a Monte Carlo setup, in order to attribute the uncertainty in projected global surface temperature change (ΔT) to three sources of uncertainty, namely on the Earth system’s response, on fossil-fuel CO2 emission and on non-CO2 co-emissions. Under the three future fuel extraction scenarios, we simulate the median ΔT to be 1.9, 2.7 or 4.0 °C in 2300, with an associated 90% confidence interval of about 65%, 52% and 42%. We show that virtually all of the total uncertainty is attributable to the uncertainty in the future Earth system’s response to the anthropogenic perturbation. We conclude that the uncertainty in emission estimates can be neglected for global temperature projections in the face of the large uncertainty in the Earth system response to the forcing of emissions. We show that this result does not hold for all variables of the climate system, such as the atmospheric partial pressure of CO2 and the

Hemophilia B with mutations at glycine-48 of factor IX exhibited delayed activation by the factor VIIa-tissue factor complex.

Science.gov (United States)

Wu, P C; Hamaguchi, N; Yu, Y S; Shen, M C; Lin, S W

2000-10-01

Gly-48 is in the conserved DGDQC sequence (residues 47-51 of human factor IX) of the first EGF (EGF-1)-like domain of factor IX. The importance of the Gly-48 is manifested by two hemophilia B patients; factor IXTainan and factor IXMalmo27, with Gly-48 replaced by arginine (designated IXG48R) and valine (IXG48V), respectively. Both patients were CRM+ exhibiting mild hemophilic episodes with 25% (former) and 19% (latter) normal clotting activities. We characterize both factor IX variants to show the roles of Gly-48 and the conservation of the DGDQC sequence in factor IX. Purified plasma and recombinant factor IX variants exhibited approximately 26%-27% normal factor IX's clotting activities with G48R or G48V mutation. Both variants depicted normal quenching of the intrinsic fluorescence by increasing concentrations of calcium ions and Tb3+, indicating that arginine and valine substitution for Gly-48 did not perturb the calcium site in the EGF-1 domain. Activation of both mutants by factor XIa appeared normal. The reduced clotting activity of factors IXG48R and IXG48V was attributed to the failure of both mutants to cleavage factor X: in the presence of only phospholipids and calcium ions, both mutants showed a 4 to approximately 7-fold elevation in Km, and by adding factor VIIIa to the system, although factor VIIIa potentiated the activation of factor X by the mutants factor IXaG48R and factor IXaG48V, a 2 to approximately 3-fold decrease in the catalytic function was observed with the mutant factor IXa's, despite that they bound factor VIIIa on the phospholipid vesicles with only slightly reduced affinity when compared to wild-type factor IXa. The apparent Kd for factor VIIIa binding was 0.83 nM for normal factor IXa, 1.74 nM for IXaG48R and 1.4 nM for IXaG48V. Strikingly, when interaction with the factor VIIa-TF complex was examined, both mutations were barely activated by the VIIa-TF complex and they also showed abnormal interaction with VIIa-TF in bovine

Factors Affecting Mitigation of Methane Emission from Ruminants: Management Strategies

Directory of Open Access Journals (Sweden)

Afshar Mirzaei-Aghsaghali

2015-06-01

Full Text Available Nowadays, greenhouse gas emission which results in elevating global temperature is an important subject of worldwide ecological and environmental concern. Among greenhouse gases, methane is considered a potent greenhouse gas with 21 times more global warming potential than carbon dioxide. Worldwide, ruminant livestock produce about 80 million metric tons of methane each year, accounting for about 28% of global emissions from human related activities. Therefore it is impelling animal scientists to finding solutions to mitigate methane emission from ruminants. It seems that solutions can be discussed in four topics including: nutrition (feeding, biotechnology, microbiology and management strategies. We have already published the first review article on feeding strategies. In the current review, management strategies such as emphasizing on animals - type and individual variability, reducing livestock numbers, improving animal productivity and longevity as well as pasture management; that can be leads to decreasing methane production from ruminant animal production are discussed.

[Research on carbon reduction potential of electric vehicles for low-carbon transportation and its influencing factors].

Science.gov (United States)

Shi, Xiao-Qing; Li, Xiao-Nuo; Yang, Jian-Xin

2013-01-01

Transportation is the key industry of urban energy consumption and carbon emissions. The transformation of conventional gasoline vehicles to new energy vehicles is an important initiative to realize the goal of developing low-carbon city through energy saving and emissions reduction, while electric vehicles (EV) will play an important role in this transition due to their advantage in energy saving and lower carbon emissions. After reviewing the existing researches on energy saving and emissions reduction of electric vehicles, this paper analyzed the factors affecting carbon emissions reduction. Combining with electric vehicles promotion program in Beijing, the paper analyzed carbon emissions and reduction potential of electric vehicles in six scenarios using the optimized energy consumption related carbon emissions model from the perspective of fuel life cycle. The scenarios included power energy structure, fuel type (energy consumption per 100 km), car type (CO2 emission factor of fuel), urban traffic conditions (speed), coal-power technologies and battery type (weight, energy efficiency). The results showed that the optimized model was able to estimate carbon emissions caused by fuel consumption more reasonably; electric vehicles had an obvious restrictive carbon reduction potential with the fluctuation of 57%-81.2% in the analysis of six influencing factors, while power energy structure and coal-power technologies play decisive roles in life-cycle carbon emissions of electric vehicles with the reduction potential of 78.1% and 81.2%, respectively. Finally, some optimized measures were proposed to reduce transport energy consumption and carbon emissions during electric vehicles promotion including improving energy structure and coal technology, popularizing energy saving technologies and electric vehicles, accelerating the battery R&D and so on. The research provides scientific basis and methods for the policy development for the transition of new energy vehicles

The importance of residues 195-206 of human blood clotting factor VII in the interaction of factor VII with tissue factor

International Nuclear Information System (INIS)

Wildgoose, P.; Kisiel, W.; Kazim, A.L.

1990-01-01

Previous studies indicated that human and bovine factor VII exhibit 71% amino acid sequence identity. In the present study, competition binding experiments revealed that the interaction of human factor VII with cell-surface human tissue factor was not inhibited by 100-fold molar excess of bovine factor VII. This finding indicated that bovine and human factor VII are not structurally homologous in the region(s) where human factor VII interacts with human tissue factor. On this premise, the authors synthesized three peptides corresponding to regions of human factor VII that exhibited marked structural dissimilarity to bovine factor VII; these regions of dissimilarity included residues 195-206, 263-274, and 314-326. Peptide 195-206 inhibited the interaction of factor VII with cell-surface tissue factor and the activation of factor X by a complex of factor VIIa and tissue factor half-maximally at concentrations of 1-2 mM. A structurally rearranged form of peptide 195-206 containing an aspartimide residue inhibited these reactions half-maximally at concentrations of 250-300 μM. In contrast, neither peptide 263-274 nor peptide 314-326, at 2 mM concentration, significantly affected either factor VIIa interaction with tissue factor or factor VIIa-mediated activation of factor X. The data provide presumptive evidence that residues 195-206 of human factor VII are involved in the interaction of human factor VII with the extracellular domain of human tissue factor apoprotein

[Coagulation factor VII levels in uremic patients and theirs influence factors].

Science.gov (United States)

Fang, Jun; Xia, Ling-Hui; Wei, Wen-Ning; Song, Shan-Jun

2004-12-01

This study was aimed to investigate coagulation factor VII level in uremic patients with chronic renal failure and to explore theirs influence factors. The plasma levels of coagulation factor VII were detected in 30 uremic patients with chronic renal failure before and after hemodialysis for 1 month, the factor VII activity (FVII:C) was determined by one-stage coagulation method, while activated factor VII (FVIIa) was measured by one-stage coagulation method using recombinant soluble tissue factor, and factor VII antigen was detected by ELISA. The results showed that: (1) The FVIIa, FVII:C and FVIIAg levels in chronic uremic patients before hemodialysis were 4.00 +/- 0.86 microg/L, (148.5 +/- 40.4)% and (99.8 +/- 21.1)% respectively, which were significantly increased, as compared with healthy controls [2.77 +/- 1.02 microg/L, (113.1 +/- 33.0)% and (73.7 +/- 18.3)% respectively, P factor VII was positively correlated with levels of blood uria nitrogen and serum creatinine before hemodialysis but not after hemodialysis. It is concluded that the enhanced levels of coagulation factor VII in chronic uremic patients suggested abnormal activated state, herperactivity and elevated production of factor VII which correlated with renal functional injury. The abnormality of factor VII in uremia may be aggravated by hemodialysis. Coagulation factor (FVII) may be a risk factor for cardiovascular events in uremic patients who especially had been accepted long-term hemodialysis.

Dynamics of ethylene production in response to compatible Nod factor

DEFF Research Database (Denmark)

Reid, Dugald; Liu, Huijun; Kelly, Simon

2018-01-01

Establishment of symbiotic nitrogen-fixation in legumes is regulated by the plant hormone ethylene, but it has remained unclear whether and how its biosynthesis is regulated by the symbiotic pathway. We established a sensitive ethylene detection system for Lotus japonicus and found that ethylene...... production increased as early as six hours after inoculation with Mesorhizobium loti. This ethylene response was dependent on Nod factor production by compatible rhizobia. Analyses of nodulation mutants showed that perception of Nod factor was required for ethylene emission, while downstream transcription...... factors including CYCLOPS, NIN and ERN1 were not required for this response. Activation of the nodulation signalling pathway in spontaneously nodulating mutants was also sufficient to elevate ethylene production. Ethylene signalling is controlled by EIN2, which is duplicated in L. japonicus. We obtained...

External Factors, Internal Factors and Self-Directed Learning Readiness

Science.gov (United States)

Ramli, Nurjannah; Muljono, Pudji; Afendi, Farit M.

2018-01-01

There are many factors which affect the level of self-directed learning readiness. This study aims to investigate the relationship between external factors, internal factors and self-directed learning readiness. This study was carried out by using a census method for fourth year students of medical program of Tadulako University. Data were…

A factor analysis to detect factors influencing building national brand

Directory of Open Access Journals (Sweden)

Naser Azad

Full Text Available Developing a national brand is one of the most important issues for development of a brand. In this study, we present factor analysis to detect the most important factors in building a national brand. The proposed study uses factor analysis to extract the most influencing factors and the sample size has been chosen from two major auto makers in Iran called Iran Khodro and Saipa. The questionnaire was designed in Likert scale and distributed among 235 experts. Cronbach alpha is calculated as 84%, which is well above the minimum desirable limit of 0.70. The implementation of factor analysis provides six factors including “cultural image of customers”, “exciting characteristics”, “competitive pricing strategies”, “perception image” and “previous perceptions”.

Global warming factors modelled for 40 generic municipal waste management scenarios

DEFF Research Database (Denmark)

Christensen, Thomas Højlund; Simion, F.; Tonini, Davide

2009-01-01

Global warming factors (kg CO2-eq.-tonne—1 of waste) have been modelled for 40 different municipal waste management scenarios involving a variety of recycling systems (paper, glass, plastic and organics) and residual waste management by landfilling, incineration or mechanical—biological waste...... treatment. For average European waste composition most waste management scenarios provided negative global warming factors and hence overall savings in greenhouse gas emissions: Scenarios with landfilling saved 0—400, scenarios with incineration saved 200—700, and scenarios with mechanical...

Procedures for measurement of anisotropy factor of neutron sources

International Nuclear Information System (INIS)

Creazolla, P.G.; Camargo, A.; Astuto, A.; Silva, F.; Pereira, W.W.

2017-01-01

Radioisotope sources of neutrons allow the production of reference fields for calibration of neutron measurement devices for radioprotection and analysis purposes. When the emission rate of these sources is isotropic, no correction is necessary. However, variations in the source capsule material and variations in the concentration of the emitting material may produce differences in its neutron emission rate relative to the source axis, this effect is called anisotropy. A proposed procedure for measuring the anisotropy factor of the sources belonging to the IRD/LNMRI/LN Neutron Metrology Laboratory using a Precision Long Counter (PLC) detector will be presented

Overflow system PM10 emission factors and rates for cotton gins

Science.gov (United States)

This manuscript is part of a series of manuscripts that characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study was...

Unloading system PM10 emission factors and rates for cotton gins

Science.gov (United States)

This manuscript is part of a series of manuscripts that characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study was...

Revisiting factors controlling methane emissions from high-Arctic tundra

DEFF Research Database (Denmark)

Mastepanov, M.; Sigsgaard, Charlotte; Tagesson, Håkan Torbern

2013-01-01

The northern latitudes are experiencing disproportionate warming relative to the mid-latitudes, and there is growing concern about feedbacks between this warming and methane production and release from high-latitude soils. Studies of methane emissions carried out in the Arctic, particularly those...

Time evolution and emission factors of aerosol particles from day and night time savannah fires

Science.gov (United States)

Vakkari, Ville; Beukes, Johan Paul; Tiitta, Petri; Venter, Andrew; Jaars, Kerneels; Josipovic, Miroslav; van Zyl, Pieter; Kulmala, Markku; Laakso, Lauri

2013-04-01

number and size of particles larger than 100 nm; if this is not accounted for the current emission factors may underestimate the CCN-sized particle yield from savannah fires by a factor of two to three. Acknowledgements This research was supported by the Academy of Finland under the project Atmospheric monitoring capacity building in Southern Africa (project number 132640), by the Saastamoinen säätiö, by the North-West University and by the Academy of Finland Center of Excellence program (project number 1118615). References IPCC, Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 2007. Pope, C. A., and Dockery, D. W.: Health effects of fine particulate air pollution: lines that connect, J Air Waste Manag. Assoc., 56, 709-742, 2006. Swap, R. J., Annegarn, H. J., Suttles, J. T., King, M. D., Platnick, S., Privette, J. L., and Scholes, R. J.: Africa burning: A thematic analysis of the Southern African Regional Science Initiative (SAFARI 2000), J. Geophys. Res., 108, 8465, doi:10.1029/2003JD003747, 2003. Vakkari, V., Beukes, J. P., Laakso, H., Mabaso, D., Pienaar, J. J., Kulmala, M., and Laakso, L.: Long-term observations of aerosol size distributions in semi-clean and polluted savannah in South Africa, Atmos. Chem. Phys. Discuss., 12, 24043-24093, doi:10.5194/acpd-12-24043-2012, 2012.

Estimation of long-term environmental inventory factors associated with land application of sewage sludge

DEFF Research Database (Denmark)

Bruun, Sander; Yoshida, Hiroko; Nielsen, Martin P.

2016-01-01

. However, because of the complexity of the agricultural production system, it is difficult to estimate emissions consistently under different conditions. In the current paper, a mechanistic agro-ecosystem model was calibrated to be able to simulate different sludge types stabilized using different...... crop response conditions (i.e. when nitrogen was limiting) and low crop response conditions (i.e. when nitrogen was not limiting). The average high response nitrogen harvest factor over the tested environmental conditions was ranging from 0.06 to 0.30 for the different sludge types included. This means...... that if an additional 1 kg of nitrogen is applied with sludge, between 0.06 and 0.30 kg additional nitrogen is harvested. This is considerably lower than for mineral fertilizer with an average value of 0.63. The low response harvest factors were considerably lower, ranging from 0.03 to 0.13. The emission factor...

Methane conversion factors from cattle manure in Mexico

Energy Technology Data Exchange (ETDEWEB)

Gonzalez-Avalos, E E:mail: egavalos@imp.mx [Instituto Mexicano del Petroleo, Mexico, D.F. (Mexico); Ruiz-Suarez, L G [Centro de Ciencias de la Atmosfera, Universidad Nacional Autonoma de Mexico, Mexico, D.F. (Mexico)

2007-01-15

Methane emission factors from different cattle manure management systems including simulated slurry system fermentation were experimentally determined in this and a previous study (Gonzalez-Avalos and Ruiz-Suarez, 2001). Combining results from both studies, we report values for maximum CH4 yield, called B0, for manure produced by cattle under different production systems and climates, which also implies different quality of feeds and associated methane conversion factors (MCF) for distinct manure management systems. This set of data has the same functionality than that of the current IPCC methodology, but offer a wider set of key parameters to estimate methane emissions from manure, which may be of interest in other countries. In this work, we report MCF can be up to 17.3 times smaller than those suggested in the 1996 Revised IPCC Methodology Guidelines (IPCC, 1997) and Good Practice Guidance (IPCC, 2000). [Spanish] Los factores de emision de metano de diferentes sistemas de manejo de excretas, incluyendo la simulacion de la fermentacion en un sistema de lechada, fueron determinados experimentalmente en este trabajo y en otro anterior (Gonzalez-Avalos y Ruiz-Suarez, 2001). Al combinar ambos, se obtuvieron valores para la produccion maxima de metano (B0) provenientes de excretas producidas por ganado bovino de diferentes sistemas de produccion y climas, lo cual implica diversas calidades de alimento y factores de conversion de metano (MCF) dependiendo de los sistemas de manejo de excretas. Este conjunto de datos tiene la misma funcionalidad que los de la metodologia actual del IPCC, pero ofrece un conjunto de parametros mas amplio para estimar las emisiones de metano por excretas, lo cual puede ser de interes en otros paises. En este trabajo se reporta que los MCF pueden ser hasta 17.3 veces mas pequenos que los sugeridos en las Directrices de la Metodologia Revisada del IPCC de 1996 (IPCC, 1997) y en la Guia de Buenas Practicas (IPCC, 2000).

Zero energy buildings and mismatch compensation factors

DEFF Research Database (Denmark)

Lund, Henrik; Marszal, Anna Joanna; Heiselberg, Per

2011-01-01

This paper takes an overall energy system approach to analysing the mismatch problem of zero energy and zero emission buildings (ZEBs). The mismatch arises from hourly differences in energy production and consumption at the building level and results in the need for exchange of electricity via...... the public grid even though the building has an annual net-exchange of zero. This paper argues that, when looked upon from the viewpoint of the overall electricity supply system, a mismatch can be both negative and positive. Moreover, there are often both an element of levelling out mismatches between...... of the energy production unit. Based on historical data for the electricity supply area in western Denmark, this paper makes a first attempt to quantify mismatch compensation factors. The results indicate that such compensation factors are a little below one for buildings with photovoltaics (PV) and a little...

Examining drivers of the emissions embodied in trade.

Directory of Open Access Journals (Sweden)

Leying Wu

Full Text Available Emissions embodied in provincial trade (EEPT have important effects on provinces' responsibilities for carbon emission reductions. Based on a multi-regional input-output model, we calculated EEPT for China's 30 provinces in 2002, 2007 and 2010, and we attempted to determine the drivers of EEPT. The results showed that, during this period, the ratio of EEPT to production-based emissions increased over time, reaching 40.24% in 2010. In consideration of its important role in carbon emissions, we analyzed the factors attributable to EEPT through structure decomposition analysis. The decomposition results showed that final demand and carbon emission intensity were two major factors in EEPT, while the final demand in other provinces and the carbon emission intensity in the local province were major factors for Emissions embodied in provincial exports and the final demand in the local province and the carbon emission intensity in other provinces were major factors for Emissions embodied in provincial imports. Regarding the differences among the EEPT of different provinces, changes in the structure of trade were the primary reason.