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1

Gonçalves, Cátia Vanessa Maio. "Contribution of biomass combustion to air pollutant emissions". Doctoral thesis, Universidade de Aveiro, 2011. http://hdl.handle.net/10773/8104.

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Doutoramento em Ciências e Engenharia do Ambiente
In Portugal, it was estimated that around 1.95 Mton/year of wood is used in residential wood burning for heating and cooking. Additionally, in the last decades, burnt forest area has also been increasing. These combustions result in high levels of toxic air pollutants and a large perturbation of atmospheric chemistry, interfere with climate and have adverse effects on health. Accurate quantification of the amounts of trace gases and particulate matter emitted from residential wood burning, agriculture and garden waste burning and forest fires on a regional and global basis is essential for various purposes, including: the investigation of several atmospheric processes, the reporting of greenhouse gas emissions, and quantification of the air pollution sources that affect human health at regional scales. In Southern Europe, data on detailed emission factors from biomass burning are rather inexistent. Emission inventories and source apportionment, photochemical and climate change models use default values obtained for US and Northern Europe biofuels. Thus, it is desirable to use more specific locally available data. The objective of this study is to characterise and quantify the contribution of biomass combustion sources to atmospheric trace gases and aerosol concentrations more representative of the national reality. Laboratory (residential wood combustion) and field (agriculture/garden waste burning and experimental wildland fires) sampling experiments were carried out. In the laboratory, after the selection of the most representative wood species and combustion equipment in Portugal, a sampling program to determine gaseous and particulate matter emission rates was set up, including organic and inorganic aerosol composition. In the field, the smoke plumes from agriculture/garden waste and experimental wildland fires were sampled. The results of this study show that the combustion equipment and biofuel type used have an important role in the emission levels and composition. Significant differences between the use of traditional combustion equipment versus modern equipments were also observed. These differences are due to higher combustion efficiency of modern equipment, reflecting the smallest amount of particulate matter, organic carbon and carbon monoxide released. With regard to experimental wildland fires in shrub dominated areas, it was observed that the largest organic fraction in the samples studied was mainly composed by vegetation pyrolysis products. The major organic components in the smoke samples were pyrolysates of vegetation cuticles, mainly comprising steradienes and sterol derivatives, carbohydrates from the breakdown of cellulose, aliphatic lipids from vegetation waxes and methoxyphenols from the lignin thermal degradation. Despite being a banned practice in our country, agriculture/garden waste burning is actually quite common. To assess the particulate matter composition, the smoke from three different agriculture/garden residues have been sampled into 3 different size fractions (PM2.5, PM2.5-10 and PM>10). Despite distribution patterns of organic compounds in particulate matter varied among residues, the amounts of phenolics (polyphenol and guaiacyl derivatives) and organic acids were always predominant over other organic compounds in the organosoluble fraction of smoke. Among biomarkers, levoglucosan, β-sitosterol and phytol were detected in appreciable amounts in the smoke of all agriculture/garden residues. In addition, inositol may be considered as an eventual tracer for the smoke from potato haulm burning. It was shown that the prevailing ambient conditions (such as high humidity in the atmosphere) likely contributed to atmospheric processes (e.g. coagulation and hygroscopic growth), which influenced the particle size characteristics of the smoke tracers, shifting their distribution to larger diameters. An assessment of household biomass consumption was also made through a national scale survey. The information obtained with the survey combined with the databases on emission factors from the laboratory and field tests allowed us to estimate the pollutant amounts emitted in each Portuguese district. In addition to a likely contribution to the improvement of emission inventories, emission factors obtained for tracer compounds in this study can be applied in receptor models to assess the contribution of biomass burning to the levels of atmospheric aerosols and their constituents obtained in monitoring campaigns in Mediterranean Europe.
Em Portugal, estima-se que 1.95 Mton/ano de lenha sejam utilizadas na queima doméstica para aquecimento e confecção de alimentos. Em simultâneo, nas últimas décadas, a área de floresta ardida também tem vindo a aumentar. Estes tipos de combustão contribuem para a libertação de quantidades elevadas de poluentes tóxicos que perturbam a química da atmosfera, interferem com o clima e possuem efeitos nefastos na saúde. A quantificação rigorosa, à escala regional e global, das emissões de gases e matéria particulada associada à queima doméstica, queima de resíduos agrícolas e fogos florestais é fundamental para vários fins, nomeadamente na investigação dos diversos processos atmosféricos, na elaboração de relatórios de emissões de gases de estufa, e na quantificação de fontes de poluição atmosférica que afectam a saúde humana. No sul da Europa, as bases de dados com factores de emissão detalhados são praticamente inexistentes. Os modelos climáticos, a modelização fotoquímica, os inventários de emissões e os estudos de identificação de fontes emissoras utilizam valores típicos obtidos para biomassa norte-americana ou do norte da Europa. Assim, é conveniente utilizar valores mais específicos obtidos localmente. Este estudo teve como principal objectivo a caracterização e quantificação dos gases e aerossóis emitidos por fontes de queima de biomassa, englobando as espécies lenhosas mais representativas da realidade nacional. Foram realizadas experiências de amostragem em laboratório (queima doméstica) e no campo (queima de resíduos agrícolas/jardim e fogos florestais controlados). Em laboratório, após selecção das espécies de biomassa e dos equipamentos de queima mais representativos em Portugal, estabeleceu-se um programa de amostragem para determinar os factores de emissão de poluentes gasosos e particulados, incluindo a composição orgânica e inorgânica dos aerossóis. Ao nível do campo, efectuou-se a amostragem das plumas de fumo resultantes da queima de resíduos agrícolas/jardim e de fogos controlados numa área dominada por espécies arbustivas. Os resultados deste estudo mostram que o tipo de equipamento de combustão e o tipo de biomassa utilizados têm um papel importante nos níveis e composição dos poluentes emitidos. Diferenças significativas entre o uso de equipamentos de combustão tradicionais versus equipamentos modernos foram observadas. Estas diferenças devem-se à maior eficiência de combustão dos equipamentos modernos, reflectindo-se na menor quantidade de matéria particulada, carbono orgânico e monóxido de carbono libertados. No que diz respeito ao fogo controlado em áreas dominadas por espécies arbustivas observou-se que a fracção orgânica estudada nas amostras de fumo é composta essencialmente por produtos resultantes da pirólise da vegetação. Estes produtos são constituídos na sua maioria por esteredienos e derivados de esteróis, hidratos de carbono resultantes da quebra das moléculas de celulose, produtos alifáticos provenientes de ceras vegetais e metoxifenóis resultantes da degradação térmica da lenhina. A queima de resíduos agrícolas e de jardim, apesar de ser uma prática proibida no nosso país, é uma realidade bastante frequente. Para avaliar a composição das emissões de alguns tipos de resíduos foram recolhidas amostras de três tamanhos diferentes (PM2.5, PM2.5-10 and PM>10). Apesar de se poder observar uma grande variabilidade em termos de compostos orgânicos dependendo do tipo de resíduo queimado, os compostos fenólicos (derivados do polifenol e guaiacil) e os ácidos orgânicos foram sempre predominantes em relação à restante fracção orgânica. O levoglucosano, o β-sitosterol e o fitol foram os traçadores de queima de biomassa detectados em quantidades mais apreciáveis na generalidade dos resíduos agrícolas e de jardim. O inositol pode ser considerado um bom traçador para as emissões resultantes da queima de rama de batata. Observou-se que as condições ambientais (tais como valores elevados de humidade relativa na atmosfera) provavelmente contribuíram para processos de coagulação e de crescimento higroscópico que influenciaram as características dos traçadores de biomassa, mudando sua distribuição para diâmetros maiores. Foi também feita a avaliação do consumo doméstico de biomassa na forma de um inquérito aplicado à escala nacional. Os resultados obtidos, conjugados com as bases de dados sobre factores de emissão obtidas nos ensaios de queima laboratoriais, permitiram estimar as quantidades emitidas de vários poluentes em cada distrito de Portugal continental. Além de contribuir significativamente para o aperfeiçoamento dos inventários de emissões, os factores de emissão obtidos para vários compostos traçadores poderão ser aplicados em modelos no receptor de forma a avaliar a contribuição da queima de biomassa para os níveis de aerossóis atmosféricas e seus constituintes obtidos em campanhas de monitorização na Europa mediterrânea.
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2

Upton, Nigel Keith. "Algorithmic solution of air-pollutant cloud models". Thesis, Cranfield University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.304572.

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3

Ogunlaja, Olumuyiwa Omotola. "Measurement of Air Pollutant Emissions from a Confined Poultry Facility". DigitalCommons@USU, 2009. https://digitalcommons.usu.edu/etd/392.

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Air emissions from animal feeding operations have become a growing concern. Much work has been done to study occupational exposures and the exhaust concentrations associated with animal facilities; however little information has been provided about air quality around the houses. Ammonia (NH3 ), ethanol (EtOH), nitrous oxide (N2O), carbon dioxide (CO2), and particulate matter (PM 2.5 and PM10) emissions were monitored in two different buildings for laying hens in northern Utah. Over the six-month sampling period, the observed average temperatures for the west and east fan banks of the high-rise building were 21.2±4 and 19.4±1.3°C, respectively, and the average inside relative humidities during the same period were 43.7±7.2 and 48.4±7.9%, respectively. Furthermore, the observed average temperatures for the west and east fan banks of the manure-belt building were 20.6±4.4 and 17.9±2.7°C, respectively, and the average percent inside relative humidities during the same period were 44.4 ±7.6 and 49.3±7.4%, respectively. The ventilation rates ranged from 0.80 m3 h-1 bird-1 to 4.80 m3 h-1 bird -1 with an average of 2.02 m3 h -1 bird -1 for the high-rise barn and from 0.80 m3 h-1 bird -1 to 6.0 m3 h-1 bird-1 with an average of 2.20 m3 h-1 bird-1 for the manure-belt building over the sampling period of September, October, November, and December 2008 and January 2009. Average NH3 emission factors were 72±17 g d-1 AU-1 for the high-rise system and 9.1±7 g d-1 AU-1 for the manure-belt (1 AU is equal to 500 kg of animal live weight). The NH3 emission reduction factor for the manure-belt technique compared to the high-rise technique was 87%. Ammonia levels outside the house appeared to be less than 1 ppm. No significant emissions were registered for N2O, H2S, and EtOH, which were consistently close to zero for both techniques. The carbon dioxide (CO2) emission factor from the high-rise building was 104±11 g day-1 AU-1 and from the manure-belt building, 105±20 g day-1 AU-1. PM emissions were greater from the manure-belt system in comparison with the high-rise system, showing mean values of 165 vs. 114 g day-1 AU-1 for PM 2.5, 1,987 vs. 1,863 g day-1 AU-1for PM10 and 4,460 vs. 3,462 g day-1 AU-1 for TSP respectively. None of the 24-h PM 2.5 measurements collected from both management techniques exceeded the U.S. EPA 24-hr National Ambient Air Quality Standard (NAAQS) of 35 μg/m 3.
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4

Rayfield, David. "Estimation of road traffic pollutant emissions in Greater Manchester". Thesis, Manchester Metropolitan University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364058.

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5

Linaritakis, Konstantinos N. "Factors affecting traffic-related air pollutant levels in urban streets". Thesis, Imperial College London, 1988. http://hdl.handle.net/10044/1/47154.

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6

Moore, Kori D. "Measurement of Agriculture-Related Air Pollutant Emissions using Point and Remote Sensors". DigitalCommons@USU, 2017. https://digitalcommons.usu.edu/etd/6907.

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Measuring air pollution emissions from agricultural activities is usually difficult because of their large area and variability. Traditional air quality sensors, called point samplers, measure conditions in one location, which may not adequately measure a plume. Remote sensors, instruments that measure pollution along a line rather than at a single point, are better able to measure conditions around large areas. This dissertation reports on four agricultural air emissions studies that used both point and remote sensors for comparison. The methods used to calculate the emissions are based on previous work and are further developed in these studies. In particular, an atmospheric dispersion model was developed and tested that can account for a particle behaving different than the surrounding gas due to gravity and inertia and depositing out of the flow. Particulate matter (PM) emissions values are reported for two agricultural tillage conservation management practices (CMPs)and the corresponding traditional tillage methods in order to determine how well the CMP reduces emissions. In addition, gas-phase ammonia (NH3) emissions for a dairy operation and PM emissions from a feedlot operation are reported. These studies can help us better measure emissions from agricultural operations and understand how much air pollution is being emitted.
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7

Mashio, Tomoka 1973. "A study of ground-level air pollutant emissions from airport mobile sources". Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/80650.

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8

Graville, Stephen Rhys. "Pollutant formation during the combustion of heavy liquid fuels". Thesis, University College London (University of London), 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262602.

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9

Chandru, Santosh. "Trans-boundary pollutant impacts of emissions in the Imperial Valley-Calexico region and from Southern California". Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/24770.

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Thesis (M. S.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2008.
Committee Chair: Russell, Armistead; Committee Member: Mulholland, James; Committee Member: Odman, Talat.
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10

Klapmeyer, Michael Evan. "Characterization of Urban Air Pollutant Emissions by Eddy Covariance using a Mobile Flux Laboratory". Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/37675.

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Air quality management strategies in the US are developed largely from estimates of emissions, some highly uncertain, rather than actual measurements. Improved knowledge based on measurements of real-world emissions is needed to increase the effectiveness of these strategies. Consequently, the objectives of this research were to (1) quantify relationships among urban emissions sources, land use, and demographics, (2) determine the spatial and temporal variability of emissions, and (3) evaluate the accuracy of official emissions estimates. These objectives guided three field campaigns that employed a unique mobile laboratory equipped to measure pollutant fluxes by eddy covariance. The first campaign, conducted in Norfolk, Virginia, represented the first time fluxes of nitrogen oxides (NOx) were measured by eddy covariance in an urban environment. Fluxes agreed to within 10% of estimates in the National Emissions Inventory (NEI), but were three times higher than those of an inventory used for air quality modeling and planning. Additionally, measured fluxes were correlated with road density and increased development. The second campaign took place in the Tijuana-San Diego border region. Distinct spatial differences in fluxes of carbon dioxide (CO2), NOx, and particles were revealed across four sampling locations with the lowest fluxes occurring in a residential neighborhood and the highest ones at a port of entry characterized by heavy motor vehicle traffic. Additionally, observed emissions of NOx and carbon monoxide were significantly higher than those in emissions inventories, suggesting the need for further refinement of the inventories. The third campaign focused on emissions at a regional airport in Roanoke, Virginia. NOx and particle number emissions indices (EIs) were calculated for aircraft, in terms of grams of pollutant emitted per kilogram of fuel burned. Observed NOx EIs were ~20% lower than those in an international databank. NOx EIs from takeoffs were significantly higher than those from taxiing, but relative differences for particle EIs were mixed. Observed NOx fluxes at the airport agreed to within 25% of estimates derived from the NEI. The results of this research will provide greater knowledge of urban impacts to air quality and will improve associated management strategies through increased accuracy of official emissions estimates.
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11

Deighton, Jacob. "Methane and Hazardous Air Pollutant Emissions from Marginally Producing “Stripper”Oil and Natural Gas Wells in Appalachian Ohio". University of Cincinnati / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1554120171141725.

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12

Meade, Wilbert E. "On Road Mobile Source Air Pollutant Emissions; Identifying Hotspots and Ranking Roads in the State of Ohio". Miami University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=miami1305070342.

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13

Lim, Guo Quan. "Evaluation of the Influence of Non-Conventional Sources of Emissions on Ambient Air Pollutant Concentrations in North Texas". Thesis, University of North Texas, 2015. https://digital.library.unt.edu/ark:/67531/metadc804841/.

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Emissions of air pollutants from non-conventional sources have been on the rise in the North Texas area over the past decade. These include primary pollutants such as volatile organic compound (VOC) and oxides of nitrogen (NOx) which also act as precursors in the formation of ozone. Most of these have been attributed to a significant increase in oil and gas production activities since 2000 within the Barnett Shale region adjacent to the Dallas-Fort Worth metroplex region. In this study, air quality concentrations measured at the Denton Airport and Dallas Hinton monitoring sites operated by the Texas Commission on Environmental Quality (TCEQ) were evaluated. VOC concentration data from canister-based sampling along with continuous measurement of oxides of nitrogen (NOx), ozone (O3), particulate matter (PM2.5), and meteorological conditions at these two sites spanning from 2000 through 2014 were employed in this study. The Dallas site is located within the urban core of one of the fastest growing cities in the United States, while the Denton site is an exurban site with rural characteristics to it. The Denton Airport site was influenced by natural gas pads surrounding it while there are very few natural gas production facilities within close proximity to the Dallas Hinton site. As of 2013, there were 1362 gas pads within a 10 mile radius to the Denton Airport site but there were only 2 within a 10 mile radius to Dallas Hinton site. The Dallas site displayed higher concentrations of NOx and much lower concentrations of VOC than the Denton site. Extremely high levels of VOC measured at the Denton site corresponded with the increase in oil and gas production activities in close proximity to the monitoring site. Ethane and propane are two major contributors to the measured VOC concentration, suggesting the influence of fugitive emissions of natural gas. In Dallas, the mean and maximum values of ozone had decreased since 2000 by about 2% and 25%, respectively. Similarly NOx decreased by 50% and 18% in the mean and maximum values. However, the mean VOC value showed a 21% decrease while the maximum value increased by about 46%. In Denton, the change in percentage of ozone and NOx were similar to Dallas but the mean VOC concentration increased by about 620% while the max value increased 1960%. Source apportionment analysis confirmed the findings by identifying the production of natural gas to be the primary source of VOC emissions in Denton, while traffic sources were more influential near the Dallas site. In light of the recent proposal by EPA to revise the ozone standard, the influence of these new unconventional sources should be further evaluated.
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14

Li, Xiang. "Characterization of Air Pollutant and Greenhouse Gas Emissions from Energy Use and Energy Production Processes in United States". Research Showcase @ CMU, 2017. http://repository.cmu.edu/dissertations/1082.

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Air pollutants and greenhouse gases are two groups of important trace components in the earth’s atmosphere that can affect local air quality, be detrimental to the human health and ecosystem, and cause climate change. Human activities, especially the energy use and energy production processes, are responsible for a significant share of air pollutants and greenhouse gases in the atmosphere. In this work, I specifically focused on characterizing air pollutants and greenhouse gas emissions from the on-road gasoline and diesel vehicles, which is an important energy use process that largely contributes to the urban air pollutions, and from the natural gas production systems, which is a major energy production process that has increased dramatically in recent years and is expected to have a long-lasting impact in the future. We conducted multi-seasonal measurements in the Fort Pitt Tunnel in Pittsburgh, PA to update the on-road vehicle emission factors, to measure the size distribution of vehicle emitted particulate matter (PM), and to quantify the volatility distributions of the vehicle emitter primary organic aerosol (POA). We also conducted mobile measurements in the Denver-Julesburg Basin, the Uintah Basin, and the Marcellus Shale to quantify facility-level VOC emission from natural gas production facilities, and I constructed a gridded (0.1° × 0.1°) methane emission inventory of natural gas production and distribution over the contiguous US. I found that the stricter emission standards were effective on regulating NOx and PM emissions of diesel vehicles and the NOx, CO and organic carbon (OC) emissions of gasoline vehicles, while the elemental carbon (EC) emissions of gasoline vehicles did not change too much over the past three decades. Vehicle-emitted particles may be largely externally mixed, and a large fraction of vehicle-emitted particles may be purely composed of volatile component. Vehicle-emitted smaller particles (10– 60 nm) are dominantly (over 75%) composed of volatile component. The size-resolved particles and particles emission factors for both gasoline and diesel vehicles are also reported in this work. I also found that the POA volatility distribution measured in the dynamometer studies can be applied to describe gas-particle partitioning of ambient POA emissions. The POA volatility distribution measured in the tunnel does not have significant diurnal or seasonal variations, which indicate that a single volatility distribution is adequate to describe the gas-particle partitioning of vehicle emitted POA in the urban environment. The facility-level VOC emission rates measured at gas production facilities in all three gas production fields are highly variable and cross a range of ~2-3 order of magnitudes. It suggests that a single VOC emission profile may not be able to characterize VOC emissions from all natural gas production facilities. My gridded methane emission inventory over the contiguous US show higher methane emissions over major natural gas production fields compared with the Environmental Protection Agency Inventory of US Greenhouse Gas Emission and Sinks (EPA GHGI) and the Emission Database for Global Atmospheric Research, version 4.2 (Edgar v4.2). The total methane emissions of the natural gas production and distribution sector estimated by my inventory are 74% and 20% higher than the Edgar v4.2 and EPA GHGI, respectively. I also run the GEOS-Chem methane simulation with my inventory and EPA GHGI and compare with the GOSAT satellite data, and results show that my inventory can improve the model and satellite comparison, but the improvement is very limited. The size-resolved emission factors of vehicle emitted particles and POA volatility distribution reported in this work can be applied by the chemical transport models to better quantify the contribution of vehicle emissions to the PM in the atmosphere. Since our measurement of VOC emissions of natural gas production facilities were conducted before EPA started to regulate VOC emissions from the O&NG production facilities in 2016, the facility-level VOC emission rates reported in this work can serve as the basis for future studies to test the effectiveness of the regulatory policies. The spatially resolved methane emission inventory of natural gas production and distribution constructed in this work can be applied to update the current default methane emission inventory of GEOS-Chem, and the updated methane emission inventory can be used as a better a priori emission field for top-down studies that inversely estimate methane emissions from atmospheric methane observation.
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15

Sá, Maria Elisa Seabra Azevedo Cunha e. "Regional and urban air quality modelling under a climate change scenario". Doctoral thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/14518.

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Doutoramento em Ciências e Engenharia do Ambiente
The better understanding of the interactions between climate change and air quality is an emerging priority for research and policy. Climate change will bring changes in the climate system, which will affect the concentration and dispersion of air pollutants. The main objective of the current study is to assess the impacts of climate change on air quality in 2050 over Portugal and Porto urban area. First, an evaluation and characterization of the air quality over mainland Portugal was performed for the period between 2002 and 2012. The results show that NO2, PM10 and O3 are the critical pollutants in Portugal. Also, the influence of meteorology on O3, NO2 and PM10 levels was investigate in the national main urban areas (Porto and Lisboa) and was verified that O3 has a statistically significant relationship with temperature in most of the components. The results also indicate that emission control strategies are primary regulators for NO2 and PM10 levels. After, understanding the national air quality problems and the influence that meteorology had in the historical air quality levels, the air quality modelling system WRF-CAMx was tested and the required inputs for the simulations were prepared to fulfil the main goal of this work. For the required air quality modelling inputs, an Emission Projections under RCP scenarios (EmiPro-RCP) model was developed to assist the estimation of future emission inventories for GHG and common air pollutants. Also, the current emissions were estimated for Portugal with a higher detailed disaggregation to improve the performance of the air quality simulations. The air quality modelling system WRF/CAMx was tested and evaluated over Portugal and Porto urban area and the results point out that is an adequate tool for the analysis of air quality under climate change. For this purpose, regional simulations of air quality during historical period and future (2045-2050) were conducted with CAMx version 6.0 to evaluate the impacts of simulated future climate and anthropogenic emission projections on air quality over the study area. The climate and the emission projections were produced under the RCP8.5 scenario. The results from the simulations point out, that if the anthropogenic emissions keep the same in 2050, the concentrations of NO2, PM10 and O3 will increase in Portugal. When, besides the climate change effects, is consider the projected anthropogenic emissions the annual mean concentrations of NO2 decrease significantly in Portugal and Porto urban area, and on the contrary the annual mean PM10 concentrations increases in Portugal and decrease in Porto urban area. The O3 results are mainly caused by the reduction of ozone precursors, getting the higher reductions in urban areas and increases in the surrounding areas. All the analysis performed for both simulations for Porto urban area support that, for PM10 and O3, there will be an increase in the occurrence of extreme values, surpassing the annual legislated parameters and having more daily exceedances. This study constitutes an innovative scientific tool to help in future air quality management in order to mitigate future climate change impacts on air quality.
A interação entre as alterações climáticas e a qualidade do ar é neste momento um assunto emergente em termos de implementação de políticas e de investigação. As alterações climáticas causarão mudanças no clima, o que irá afetar a concentração e dispersão dos poluentes atmosféricos. Assim, o principal objetivo deste trabalho é avaliar os impactos das alterações climáticas na qualidade do ar em 2050 em Portugal e na área urbana do Porto. Numa primeira fase, realizou-se uma caracterização da qualidade do ar em Portugal para o período de 2002 a 2012, na qual se identificou que os poluentes NO2, PM10 e O3 são os mais críticos em termos de qualidade do ar. Adicionalmente, foi analisada a influência da meteorologia na qualidade do ar para esses três poluentes nas duas maiores áreas urbanas nacionais (Porto e Lisboa), sendo que o O3 é estatisticamente dependente da temperatura na maioria das suas componentes. Após o entendimento dos problemas de qualidade do ar nacionais e da influência da meteorologia nos mesmos, o sistema de modelos WRF-CAMx foi testado e todos os seus dados de entrada foram preparados. As emissões nacionais atuais foram estimadas com maior detalhe de desagregação para melhorar as simulações de qualidade do ar; o modelo de emissões, EmiPro-RCP, foi desenvolvido para estimar as emissões de 2050 tendo em conta os cenários de emissão RCPs. O sistema de modelos WRF-CAMx foi testado e avaliado para Portugal e para a área urbana do Porto, verificando-se que é uma ferramenta adequada para realizar as simulações de qualidade do ar em cenário climático. Realizaram-se simulações regionais com o modelo CAMx versão 6.0, para dois períodos: histórico e futuro (2045-2050), de forma a simular os impactos do clima futuro e das futuras emissões antropogénicas na qualidade do ar para a região de estudo. O cenário climático, bem como as emissões, foram projetadas tendo como base o cenário RCP8.5. Os resultados provenientes das simulações demonstram que, se as emissões antropogénicas se mantiverem constantes em 2050, as concentrações de NO2, PM10 e O3 irão aumentar em Portugal. Quando, aos efeitos das alterações climáticas se juntaram as futuras emissões antropogénicas, verifica-se que as concentrações médias anuais de NO2 irão diminuir e as concentrações médias anuais de PM10 aumentam em Portugal e diminuem na área urbana do Porto. Os resultados de O3 estão relacionados com as variações de concentração dos seus precursores, verificando-se as maiores reduções nas áreas urbanas e os aumentos nas áreas suburbanas. Toda a análise realizada aos dados das simulações para a área urbana do Porto indica que, no caso de PM10 e O3, irá existir um aumento de ocorrência de valores extremos de concentração, ultrapassando os valores legislados de cada poluente. Este estudo constitui uma ferramenta científica inovadora que pode ser relevante para uma futura e cuidada gestão da qualidade do ar, de forma a mitigar os impactes das alterações climáticas na qualidade do ar.
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16

Lee, Jae Choon. "The Effects of Urban Form on Vehicle Emissions - Focusing On Urban Form Factors and Three Conventional Air Pollutions and Carbon Dioxide -". The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1354657016.

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17

Ribeiro, Isabel Lavrador. "The impact of biofuels for road traffic on air quality : a modelling approach". Doctoral thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/13948.

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Doutoramento em Ciências e Engenharia do Ambiente
The selection of the energy source to power the transport sector is one of the main current concerns, not only relative with the energy paradigm but also due to the strong influence of road traffic in urban areas, which highly affects human exposure to air pollutants and human health and quality of life. Due to current important technical limitations of advanced energy sources for transportation purposes, biofuels are seen as an alternative way to power the world’s motor vehicles in a near-future, helping to reduce GHG emissions while at the same time stimulating rural development. Motivated by European strategies, Portugal, has been betting on biofuels to meet the Directive 2009/28/CE goals for road transports using biofuels, especially biodiesel, even though, there is unawareness regarding its impacts on air quality. In this sense, this work intends to clarify this issue by trying to answer the following question: can biodiesel use contribute to a better air quality over Portugal, particularly over urban areas? The first step of this work consisted on the characterization of the national biodiesel supply chain, which allows verifying that the biodiesel chain has problems of sustainability as it depends on raw materials importation, therefore not contributing to reduce the external energy dependence. Next, atmospheric pollutant emissions and air quality impacts associated to the biodiesel use on road transports were assessed, over Portugal and in particular over the Porto urban area, making use of the WRF-EURAD mesoscale numerical modelling system. For that, two emission scenarios were defined: a reference situation without biodiesel use and a scenario reflecting the use of a B20 fuel. Through the comparison of both scenarios, it was verified that the use of B20 fuels helps in controlling air pollution, promoting reductions on PM10, PM2.5, CO and total NMVOC concentrations. It was also verified that NO2 concentrations decrease over the mainland Portugal, but increase in the Porto urban area, as well as formaldehyde, acetaldehyde and acrolein emissions in the both case studies. However, the use of pure diesel is more injurious for human health due to its dominant VOC which have higher chronic hazard quotients and hazard indices when compared to B20.
A escolha de fontes energéticas para o sector dos transportes é uma das preocupações da sociedade moderna devido a questões relacionadas com o paradigma energético, e ao facto de este ser uma das principais fontes de polução do ar nas cidades, afectando significativamente a saúde humana e a sua qualidade de vida. Devido às limitações técnicas com que as formas de mobilidade avançadas ainda se deparam, os biocombustíveis são considerados uma alternativa viável para as próximas décadas, contribuindo para a redução de gases com efeito de estufa e estimulando o desenvolvimento rural. Portugal, motivado pelas políticas Europeias, tem aposto nos biocombustíveis, em especial no biodiesel, a fim de atingir a meta da Directiva 2009/28/CE. No entanto, não são conhecidos os impactos na qualidade do ar decorrentes da utilização de biodiesel. Assim, este trabalho pretende clarificar esta situação respondendo à seguinte questão: a utilização de biodiesel promove uma melhoria na qualidade do ar em Portugal, particularmente nas áreas urbanas? A primeira tarefa deste trabalho consistiu na caracterização da cadeia de biocombustíveis em Portugal, verificando-se que a cadeia tem problemas de sustentabilidade, uma vez que toda a matéria-prima usada é importada, não estando a promover a redução da dependência energética externa. Posteriormente foram avaliados os impactos associados à utilização de biodiesel nas emissões de poluentes atmosféricos e na qualidade do ar em Portugal e em particular na área urbana do Porto, através da utilização do sistema de modelação numérica à mesoscala WRF-EURAD e tendo por base 2 cenários de emissões: o cenário de referência que considera que não é usado biodiesel e o cenário B20 que reflecte a utilização de um combustível constituído por 80% de gasóleo fóssil e 20% de biodiesel. Com este trabalho, verificou-se que o uso de B20 pode ajudar a controlar os níveis de poluição atmosférica tanto em Portugal como na área urbana do Porto, promovendo a redução das emissões de PM10, PM2.5, CO e COVNM e respectivas concentrações no ambiente atmosférico. Por outro lado, são esperados aumentos nas emissões de formaldeído, acetaldeído e acroleína com o uso de B20 e aumentos nas concentrações de NO2 na área urbana do Porto. Apesar destes compostos serem considerados tóxicos e cancerígenos, os COVNM dominantes no gasóleo de origem fóssil, presentes em quantidades reduzidas no biodiesel, têm coeficientes de perigo crónico mais elevados. Assim, a utilização de B20 nos transportes rodoviários apresenta maiores benefícios para a saúde humana e para a qualidade do ar quando comparado com a utilização de gasóleo convencional.
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18

Dohanich, Francis Albert. "On-Road Remote Sensing of Motor Vehicle Emissions: Associations between Exhaust Pollutant Levels and Vehicle Parameters for Arizona, California, Colorado, Illinois, Texas, and Utah". Thesis, University of North Texas, 2003. https://digital.library.unt.edu/ark:/67531/metadc5524/.

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On-road remote sensing has the ability to operate in real-time, and under real world conditions, making it an ideal candidate for detecting gross polluters on major freeways and thoroughfares. In this study, remote sensing was employed to detect carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxide (NO). On-road remote sensing data taken from measurements performed in six states, (Arizona, California, Colorado, Illinois, Texas, and Utah) were cleaned and analyzed. Data mining and exploration were first undertaken in order to search for relationships among variables such as make, year, engine type, vehicle weight, and location. Descriptive statistics were obtained for the three pollutants of interest. The data were found to have non-normal distributions. Applied transformations were ineffective, and nonparametric tests were applied. Due to the extremely large sample size of the dataset (508,617 records), nonparametric tests resulted in "p" values that demonstrated "significance." The general linear model was selected due to its ability to handle data with non-normal distributions. The general linear model was run on each pollutant with output producing descriptive statistics, profile plots, between-subjects effects, and estimated marginal means. Due to insufficient data within certain cells, results were not obtained for gross vehicle weight and engine type. The "year" variable was not directly analyzed in the GLM because "year" was employed in a weighted least squares transformation. "Year" was found to be a source of heteroscedasticity; and therefore, the basis of a least-squares transformation. Grouped-years were analyzed using medians, and the results were displayed graphically. Based on the GLM results and descriptives, Japanese vehicles typically had the lowest CO, HC, and NO emissions, while American vehicles ranked high for the three. Illinois, ranked lowest for CO, while Texas ranked highest. Illinois and Colorado were lowest for HC emissions, while Utah and California were highest. For NO, Colorado ranked highest with Texas and Arizona, lowest.
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19

Weger, Coenen Lindsey [Verfasser], Mark [Akademischer Betreuer] Lawrence, Bodo [Akademischer Betreuer] Bookhagen, Mark [Gutachter] Lawrence, Andreas [Gutachter] Goldthau y Noelle Eckley [Gutachter] Selin. "Exploring potential impacts from transitions in German and European energy on GHG and air pollutant emissions and on ozone air quality / Lindsey Weger Coenen ; Gutachter: Mark Lawrence, Andreas Goldthau, Noelle Eckley Selin ; Mark Lawrence, Bodo Bookhagen". Potsdam : Universität Potsdam, 2021. http://d-nb.info/1230468315/34.

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20

Wu, Hao. "Assessing urban air quality through measurements and modelling and its implications for human exposure assessment". Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/28755.

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Outdoor air pollution is a major contributor to adverse health effects of citizens, in particular those living in urban environments. Air quality monitoring networks are set up to measure air quality in different environments in compliance with national and European legislation. Generally, only a few fixed monitoring sites are located within a city and thus cannot represent air pollutant concentrations in urban areas accurately enough to allow for a detailed human exposure assessment. Other approaches to derive detailed urban air pollutant concentration estimates exist, such as dispersion models and land-use regression (LUR) models. Low-cost portable air quality monitors are also emerging, which have the potential to add value to existing monitoring networks by providing measurements at greater spatial resolution and also to provide individual-level exposure assessment. The aim of this thesis is to demonstrate how measurements and modelling in combination allow detailed investigations of the variability of air pollutants in space and time in urban area, and in turn improve on the current exposure assessment methods. Three types of low-cost portable monitors measuring NO2, O3 (Aeroqual monitors) and PM2.5 (microPEM monitor) were evaluated against their respective reference instruments. The Aeroqual O3 monitor showed very good correlation (r2 > 0.9) with the respective reference instruments, but biases in the slope and intercept coefficients indicated that calibration of Aeroqual O3 monitor was needed. The Aeroqual NO2 monitor was subject to cross-sensitivity from O3, which, as demonstrated, can be effectively corrected by making O3 and NO2 measurements in tandem. Correlation between the microPEM monitor and its reference instrument was poor (r2 < 0.1) when PM2.5 concentrations were low (< 10 μg m-3), but significantly improved (r2 > 0.69) during periods with elevated PM2.5 concentrations. Relative humidity was not found to affect the raw results of PM2.5 measurements in a consistent manner. All three types of monitors cannot be used as equivalent or indicative methods instead of reference methods in studies that require quantification of absolute pollutant concentrations. However, the generally good correlations with reference instruments reassure their application in studies of relative trends of air pollution. Concentrations of PM2.5, ultrafine particles (UFP) and black carbon (BC) were quantified using portable monitors through a combination of mobile and static measurements in the city of Edinburgh, UK. The spatial variability of UFP and BC was large, of similar magnitude and about 3 times higher than the spatial variability of PM2.5. Elevated concentrations of UFP and BC were observed along streets with high traffic volumes whereas PM2.5 showed less variation between streets and a footpath without road traffic. Both BC and UFP significantly correlated with traffic counts, while no significant correlation between PM2.5 and traffic counts was observed. The relationships between UFP, NO2 and inorganic components of PM2.5 were further investigated through long-term measurements at roadside, urban background and rural sites. UFP moderately correlated with NOx (NO2 + NO) and showed varying relationships with NOx depending on the particle size distribution. Principal component analysis and air-mass back trajectory analysis revealed that PM2.5 concentrations were dominated by long-range transport of secondary inorganic aerosols, whereas UFP were mainly related to varying local emissions and meteorological conditions. These findings imply the need for different policies for managing human exposure to these different particle components: control of much BC and UFP appears to be manageable at local scale by restricting traffic emissions; however, abatement of PM2.5 requires a more strategic approach, in cooperation with other regions and countries on emissions control to curb long-range transport of PM2.5 precursors. A dispersion model (ADMS-Urban) was used to simulate high resolution NO2 and O3 concentrations in Edinburgh. The effects of different emission and meteorological input datasets on the resulting modelled NO2 concentrations were investigated. The modelled NO2 and O3 concentrations using the optimal model setup were validated against reference instrument and diffusion tube measurements. Temporal variability of NO2 was predicted well at locations that were not heavily influenced by local effects, such as road junctions and bus stops. Temporal variability of O3 was predicted better than for NO2. Long-term spatial variability of NO2 was found to correlate well with diffusion tube measurements, while modelled spatial variability of O3 in ADMS-Urban compared poorly with diffusion tube measurements. However, it was found that the O3 diffusion tube measurements may be subject to some unidentified biases affecting their accuracy. Land-use regression (LUR) models are widely used to estimate exposure to air pollution in urban areas. An appropriately sized and designed monitoring network is an important component for the development of a robust LUR model. Concentrations of NO2 were simulated by ADMS-Urban at ‘virtual’ monitoring sites in 54 different network designs of varying numbers and types of site, using a 25 km2 area including much of the Edinburgh city area. Separate LUR models were developed for each network. These LUR models were then used to estimate ambient NO2 concentrations at all residential addresses, which were evaluated against the ADMS-Urban modelled concentration at these addresses. The improvement in predictive capability of the LUR models was insignificant above ~30 monitoring sites, although more sites tended to yield more precise LUR models. Monitoring networks containing sites located within highly populated areas better estimated NO2 concentrations across all residential locations. LUR models constructed from networks containing more roadside sites better characterised the high end of residential NO2 concentrations but had increased errors when considering the whole range of concentrations. No particular composition of monitoring network resulted in good estimation simultaneously across all residential NO2 concentration and of the highest NO2 levels implying a lack of spatial contrast in LUR-modelled pollution surface compared with the dispersion model. Finally, the results from the measurement and modelling studies presented in thesis are synthesised in the context of current exposure assessment studies. Low-cost air-quality monitors currently do not possess and are unlikely in the near future to provide the robustness and accuracy to replace the existing routine monitoring network. Development of the low-cost air-quality should be aiming at upgrading them as the indicative method as defined in the data quality objective in the EU directive. The monitoring sites used to build LUR models should capture well the population distribution in the study area as opposed to capturing the greatest pollution contrast. The traditional methods of evaluating LUR models are also ineffective in characterising the models’ capability at estimating pollutant concentration at residential address. Given that the dispersion models are also subject to the availability and uncertainties in the input data, future air quality model development should endeavour to incorporate both dispersion and land-use regression models, where the uncertainty in the input data can be reduced by using LUR models built on actual measurements, and the limitation in the statistical modelling can be replaced by adopting the deterministic approach used in the dispersion model.
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21

Pattinson, Woodrow Jules. "An investigation into local air quality throughout two residential communities bisected by major highways in South Auckland, New Zealand". Thesis, University of Canterbury. Environmental Science, 2014. http://hdl.handle.net/10092/10002.

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Population exposure to traffic pollution is a rapidly developing, multi-disciplinary scientific field. While the link between long-term exposure and respiratory issues is well-established, there are probable links to a number of more serious health effects, which are still not fully understood. In the interests of protecting human health, it is prudent that we take a cautionary approach and actively seek to reduce exposure levels, especially in the home environment where people spend a significant portion of their time. In many large cities, a substantial number of homes are situated on land immediately adjacent to busy freeways and other heavily-trafficked roads. Characterising exposures of local residents is incredibly challenging but necessary for advancing epidemiological understandings. While existing studies are plentiful, the results are mixed and generally not transferable to other urban areas due to the localised nature of the built environment and meteorological influences. This thesis aimed to employ a variety of methods to develop a holistic understanding of the influence of traffic emissions on near-highway residents' exposure in two communities of South Auckland, New Zealand, where Annual Average Daily Traffic (AADT) is as high as 122,000 vehicles. First, ultrafine particles (UFPs), nitrogen oxides (NOx), carbon monoxide (CO) and particulate matter ≤ 10 μm (PM₁₀) were continuously monitored using a series of fixed stations at different distances from the highways, over several months during the winters of 2010 and 2011. Emissions modelling output (based on traffic composition), was used within a dispersion model to compare modelled concentrations with monitored levels. In addition, community census meshblock units were mapped by level of social deprivation in order to assess potential inequities in highway emissions exposure. The second layer of local air quality investigation involved using a bicycle platform to systematically measure concentrations of UFPs, CO and PM₁₀ using the entire street-grid network throughout each community. This was done forty times - five times at four times of day (07:00, 12:00, 17:00 and 22:00), for each study area, with the aim of mapping the diurnal fluctuation of microspatial variation in concentrations. Using global positioning system (GPS) data and geographical information system (GIS) software, spatially-resolved pollutant levels were pooled by time of day and the median values mapped, providing a visualisation of the spatial extent of the influence of emissions from the highways compared to minor roads. The third layer involved using data from multiple ambient monitors, both within the local areas and around the city, to simulate fifty-four residents' personal exposure for the month of June, 2010. This required collecting timeactivity information which was carried out by door-to-door surveying. The time-activity data were transformed into microenvironment and activity codes reflecting residents movements across a typical week, which were then run through the US-EPA's Air Pollution Exposure Model (APEX). APEX is a probabilistic population exposure model for which the user sets numerous microenvironmental parameters such as Air Exchange Rates (AERs) and infiltration factors, which are used in combination with air pollutant concentrations, meteorological, and geospatial data, to calculate individuals' exposures. Simulated exposure outputs were grouped by residents' occupations and their home addresses were artificially placed at varying distances from the highways. The effects of residential proximity to the highway, occupation, work destination and commute distance were explored using a Generalised Linear Model (GLM). Surveyed residents were also asked a series of Likert-type, ordered response questions relating to their perceptions and understandings of the potential impacts of living near a significant emissions source. Their response scores were explored as a function of proximity to the highway using multivariate linear regression. This formed the final layer of this investigation into air quality throughout these South Auckland communities of Otahuhu and Mangere Bridge. Results show that concentrations of primary traffic pollutants (UFPs, NOx, CO) are elevated by 41 - 64% within the roadside corridor compared to setback distances approximately 150 m away and that the spatial extent of UFPs can reach up to 650 m downwind early in the morning and late in the evening. Further, social deprivation mapping revealed that 100% of all census meshblocks within 150 m either side of both highways are at the extreme end of the deprivation index (NZDep levels 8 - 10). Simulations for residents dispersed across the community of Otahuhu estimated daily NOx and CO exposure would increase by 32 and 37% (p<0.001) if they lived immediately downwind of the highway. If they were to shift 100 m further downwind, daily exposure would decline by 56 - 70% (p<0.001). The difference in individuals' exposure levels by occupation varied across the same distance by a factor of eight (p<0.05), with unemployed or retired persons the most exposed due to having more free time to spend outdoors at home (recreation, gardening, etc.). Those working in ventilated offices were the least exposed, even though ambient concentrations - likely due to a strong urban street canyon effect - were higher than the nearest highway monitor (5 m downwind) by 25 - 30% for NOx and CO, respectively. Inverse linear relationships were identified for distance from highway and measures of concern for health impacts, as well as for noise (p<0.05). Positive linear relationships were identified for distance from highway and ratings of both outdoor and indoor air quality (p<0.05). Measures of level of income had no conclusive statistically significant effect on perceptions (p>0.05). The main findings within this thesis demonstrate that those living within the highway corridor are disproportionately exposed to elevated long-term average concentrations of toxic air pollutants which may impact on physical health. While the socioeconomic characteristics could also heighten susceptibility to potential health impacts in these areas, certain activity patterns can help mitigate exposure. This thesis has also shown that there may be quantifiable psychological benefits of a separation buffer of at least 100 m alongside major highways. These results enhance a very limited knowledge base on the impacts of near-roadway pollution in New Zealand. Furthermore, the results lend additional support to the international literature which is working to reduce residential exposures and population exposure disparities through better policies and improved environmental planning. Where possible, the placement of sensitive population groups within highway corridors, e.g. retirement homes, social housing complexes, schools and childcare centres, should be avoided.
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22

VENTURA, LORIS. "Development and assessment of model-based and sensor-based algorithms for combustion and emission control in diesel engines". Doctoral thesis, Politecnico di Torino, 2022. http://hdl.handle.net/11583/2971995.

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23

Xiu, Meng. "Evaluating the emission of air pollutants from different sources". Thesis, Queensland University of Technology, 2022. https://eprints.qut.edu.au/235386/1/Meng%2BXiu%2BThesis%284%29.pdf.

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This thesis is an evaluative study of air pollution emissions from different sources in Australia and overseas. It investigates indoor and outdoor sources, including indoor combustion, electric equipment, asphalt pavement, forest fires and vehicular traffic. Based on evaluating sources, a simple practical method is proposed to identify pollution sources. This research has important scientific implications and potential for future practical applications, given the paucity of quantitative air quality studies available for pollution control.
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24

Tzillah, Aisha. "The Emissions of Criteria Air Pollutants from Biodiesel Fuel Usage". University of Cincinnati / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1258667095.

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25

Stettler, Marc Emil John. "Aviation emissions of black carbon and other air pollutants". Thesis, University of Cambridge, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.648379.

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26

Cousins, Ian T. "Air-soil exchange of persistent organic pollutants (POPs)". Thesis, Lancaster University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310506.

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27

Pullen, Jon. "The effects of acidic air pollutants on concrete". Thesis, Open University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357226.

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28

Alanezi, Salwa. "Emission inventories from Kuwait petroleum refineries and respective ground level concentration of pollutants in the neighboring residential area". Thesis, Loughborough University, 2013. https://dspace.lboro.ac.uk/2134/12544.

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The State of Kuwait has three large refineries, namely, Mina Al Ahmadi Refinery, Mina Abdullah Refinery and Shuaiba Refinery. These refineries process and refine Kuwait Crude Oil through different process units. There are many heaters, boilers and flares that form a part of the complicated equipment which enhance the different petroleum processes. Fuel gas is used as a firing fuel for those heaters and boilers. As a result, stack emissions like SO2, NOx, CO are predominantly present in the flue gases and this study focuses on those emissions and their impact on the surrounding residential area. The area of interest will be Umm Al-Hyman residential area. This study accumulates emission inventories from the three refineries and the respective ground level concentration of the pollutants in the neighboring residential area. It also focuses on the impact of emissions from the refinery operations on the ground level concentrations in the surrounding areas by using the inventory model and latest emission factors to provide accurate emission estimates. The models were developed and the results were verified with the actual data from the area of impact. As a result of the findings of the major pollutants, namely SO2, NOx & CO, it is found that SO2 and CO are not exceeding Kuwait EPA Ambient Air Quality Standards for Residential Areas normally. However, NOx is observed to exceed occasionally. Even though, NOx emissions from refineries sources represented by plume models were much less, there is a consistent increase in the measured NOx. Furthermore, in 2007, the measured hourly, daily and annual NOx concentration exceeded the international standard many times. The increasing trend in NOx is attributed to continuous increase in population and the number of motor vehicles. The study will go further step in recommending engineering solutions and best practices to reduce the pollutants concentrations which will help in the reduction of human health risks and protect the environment.
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29

Field, Robert Alexander. "The sources and behaviour of selected urban air pollutants". Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.309084.

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30

Allen, Deborah. "The removal of gaseous pollutants during coal combustion". Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335690.

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31

Manomaiphiboon, Kasemsan. "Estimation of Emission Strength and Air Pollutant Concentrations by Lagrangian Particle Modeling". Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/5141.

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A Lagrangian particle model was applied to estimating emission strength and air pollutant concentrations specifically for the short-range dispersion of an air pollutant in the atmospheric boundary layer. The model performance was evaluated with experimental data. The model was then used as the platform of parametric uncertainty analysis, in which effects of uncertainties in five parameters (Monin-Obukhov length, friction velocity, roughness height, mixing height, and the universal constant of the random component) of the model on mean ground-level concentrations were examined under slightly and moderately stable conditions. The analysis was performed under a probabilistic framework using Monte Carlo simulations with Latin hypercube sampling and linear regression modeling. In addition, four studies related to the Lagrangian particle modeling was included. They are an alternative technique of formulating joint probability density functions of velocity for atmospheric turbulence based on the Koehler-Symanowski technique, analysis of local increments in a multidimensional single-particle Lagrangian particle model using the algebra of Ito integrals and the Wagner-Platen formula, analogy between the diffusion limit of Lagrangian particle models and the classical theory of turbulent diffusion, and evaluation of some proposed forms of the Lagrangian velocity autocorrelation of turbulence.
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32

Rantanen, Leena. "Interactions between effects of air pollutants and nutrient status of trees". Thesis, Lancaster University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385651.

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33

Frost, David Lloyd. "Effects of atmospheric air pollutants on leaf growth of hybrid poplar". Thesis, Lancaster University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357593.

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34

Rashed, Mahmud Buagela. "A budget for selected pollutants for a major rural motorway". Thesis, Lancaster University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.279650.

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35

Goldstone, Mark Edward. "The behaviour and control of motor vehicle related pollutants in urban air". Thesis, Imperial College London, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.260759.

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36

Dawod, Abdulkadir Mohamed. "The effect of acidifying pollutants deposition on organic upland soils in the UK". Thesis, University of Aberdeen, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.360351.

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This Thesis presents the results of various studies on peat soils and organic surface horizons of peaty podzols derived from acidification-sensitive parent materials. It aims primarily at finding out which peat and organic surface horizon chemical properties correlate most significantly with acidifying deposition parameters, the effect that acidifying pollutant deposition has on growth of vegetation (Calluna vulgaris) and litter decomposition, and the fate of ammonia in peat soils. Two regional surveys were carried out throughout Scotland. Significant correlations were found particularly between the chemical properties of peat and the effective concentrations of the acidifying deposition components. The more significant correlations found with peat pH(water), rather than with pH(CaCl2), point to the fact that the mobile anion effect is important. A method was established for estimating the pH of soil solution at field conditions, i.e. at a dilution factor of unity, and a close similarity was subsequently found between this estimated pH and the effective pH of deposition. It is suggested that this provides an excellent basis for pH prediction for ombrotrophic peats. Significant seasonal variations in peat chemistry were found, with peat pH(water), for example, varying by up to 0.4 pH units throughout the year. A 7-month pot experiment demonstrated significantly lower growth rates of Calluna vulgaris, and slower litter decomposition rates, at higher acidifying deposition inputs. Studies on the retention of NH4+ in peats clearly show that there is only a limited capacity for biological immobilisation of NH4+ at high input concentrations. More information is needed on the fate of NH4+ inputs in the soil, and on the extent to which retention is via cation exchange and biological uptake, and this needs to be taken into consideration when setting critical loads for N.
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37

Ottley, Christopher John. "An evaluation of atmospheric dry deposition of selected pollutants to the North Sea". Thesis, University of Essex, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.292875.

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38

Peng, Chiung-Yu. "Identification and quantification of volatile organic compound emissions from buildings and heating, ventilating and air conditioning systems". Ann Arbor, Mich. : University of Michigan, 1998. http://books.google.com/books?id=yxIvAAAAMAAJ.

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39

Karlsson, Hanna. "Particularly harmful particles? : a study of airborne particles with a focus on genotoxicity and oxidative stress /". Stockholm, 2006. http://diss.kib.ki.se/2006/91-7140-972-6/.

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40

Heng, Yen. "Accounting for Greenhouse Gas Emissions and Toxic Air Pollutants in Trucking Efficiency and Productivity". Thesis, North Dakota State University, 2011. https://hdl.handle.net/10365/29553.

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Air pollution is a threat to the environment and human health. Freight trucking in particular is the main source of freight transportation emissions. Heavy-duty trucks emit large amounts of toxic air pollutants that cause serious diseases and harm public health. In addition, heavy-duty trucks emit great amounts of greenhouse gas (GHG), which is the leading cause of global warming. Despite increased environmental restrictions on air pollution and rising trucking greenhouse gas emissions in the past decades, no economic study has examined the potential GHG and air pollution reductions in the trucking sector and the associated private abatement costs to the industry. This study accounts for GHG emissions and toxic air pollutants in measuring and evaluating efficiency and productivity for the trucking industry in the 48 contiguous states. Moreover, the private costs of abatement to the industry were also estimated. When only GHG was incorporated in the production model, the results showed that each state could expand desirable output and reduce GHG by an average of 11 percent per year between 2000 and 2007. The Malmquist-Luenberger productivity indexes showed that omitting or ignoring GHG in trucking service production yielded biased estimates. On the other hand, due to increased environmental regulations, most of the toxic air pollutants decreased dramatically between 2002 and 2005. The analytical results showed that inefficiency decreased during this period. The private costs of abatement averaged $73 million per state in 2005. When GHG and six toxic air pollutants were incorporated in the production model, the estimated private abatement cost was $76 million per state, which was equivalent to 0.7 percent of the industry output in 2005.
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41

Martínez, Villa Gerardo. "A study of nitrous acid and other air pollutants in the Greater London area". Thesis, Imperial College London, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.251836.

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42

Douce, David Stewart. "Air quality assessment and the use of specific markers to apportion pollutants to source". Thesis, Sheffield Hallam University, 1998. http://shura.shu.ac.uk/19672/.

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The contributions of specific polluting sources to both indoor and outdoor atmospheric pollution are difficult to determine, as solid and gaseous products from different combustion sources are often similar. Sometimes, however, a marker compound can be identified that is unique to a pollution source (or at least not present in most other local combustion sources) and which will allow assessment of the contribution of that source to total atmospheric pollution. The aim of this study was to identify suitable marker compounds and methods for the apportionment (assessment of percentage contribution) of specific sources to atmospheric pollution. The sources selected were diesel exhaust emissions in outdoor, and environmental tobacco smoke (ETS) in indoor environments. Studies with controlled (laboratory) atmospheres would be followed by field studies using these methods and markers to produce apportionments for these sources to air pollution in selected environments. Initial analysis of such polluting sources was therefore the qualitative analysis of volatile compounds and particulate associated material, both organic and inorganic. Volatile organic compounds were adsorbed onto various resins, while particulate material was sampled onto various filter paper types. Organics were determined by GC-AED and GC-MS, and elements by ICP-MS.1-Nitropyrene was identified as a suitable marker for diesel particulate emissions (< 5um). A large volume air sample from Sheffield city centre using 1-nitropyrene as a marker suggested that 63% of atmospheric particulate material (< 5um) might be of diesel origin. However the concentration of 1-nitropyrene is low in atmospheric samples, and in the volumes used in routine sampling the amount of 1-nitropyrene was below the limit of detection on the instrument used. In an alternative approach the aliphatic alkane tetracosane (C24) was used as a diesel marker for urban air, with a 1-nitropyrene:tetracosane ratio derived from the average results from laboratory experiments with a diesel engine running at various speeds and loads. This approach yielded apportionment values ranging from 5-85% for the diesel contribution to particulate material (< 5mum) in the urban air of Sheffield. No volatile marker compound was found for diesel apportionment. The contribution of ETS to atmospheric pollution has previously been estimated from the measurement of respirable suspended particulates (RSP), which was superseded by total UV absorbance and total fluorescence of a methanol extract. More recent work has suggested the use of solanesol or scopoletin as marker compounds. This thesis shows that the non specific methods overestimated the particulate contribution of ETS in some atmospheres, and that solanesol is a better marker compound than scopoletin. Preliminary studies from a small number of smokers homes and offices, with solanesol as a marker compound for particulate ETS, indicated that ETS contributions to total particulate material (< 5mum) ranged from 6 to 49% in homes and 11 to 28% in offices. Pyrrole was used as a marker for ETS contribution to volatile organic pollution, and studies with controlled atmospheres with a smoking machine allowed calculation of the ratios of pyrrole to other volatile organic compounds (VOC's) in ETS. Samples from the field study were used to produce apportionment percentage levels of benzene, toluene, o-xylene and p+m-xylene associated with ETS.In addition the use of tree bark as a atmospheric sink for airborne particulates was investigated. Six nitrated polycyclic aromatic hydrocarbons associated with diesel emissions were quantified in bark extracts and levels of these were found to be highest during winter months.
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43

Schreiber, Ute. "Luftschadstoff- und Treibhausgasemissionen in Sachsen". Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-89094.

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Dargestellt werden die Verursacher von Luftschadstoffen und Treibhausgasen, u. a. Groß- und Kleinfeuerungsanlagen, Verkehr und Landwirtschaft sowie der prozentuale Anteil ihrer Emissionen. Dazu gehören beispielsweise Kohlendioxid, Methan, Lachgas und die Luftschadstoffe Kohlenmonoxid, Schwefel- und Stickoxide, leicht flüchtige Stoffe, Staub und Feinstaub, Ammoniak, persistente organische Stoffe und Schwermetalle. Nach den deutlichen Verbesserungen der Luftqualität in den 1990er-Jahren haben sich die Emissionen von Luftschadstoffen und Treibhausgasen in den letzten 10 Jahren auf einem stabilen Niveau eingependelt. Mit Ausnahme von Kohlendioxid und Schwefeldioxid liegt Sachsen bei den Luftschadstoffen unter dem Bundesdurchschnitt.
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44

Hassan, Abdel Galiel A. "Computer modelling of the dispersion of air pollutants associated with vehicle emissions in street canyons". Thesis, Glasgow Caledonian University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.688238.

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45

Al-Sulaiman, Sabah. "The formation, distribution and behaviour of gaseous pollutants in the Shuaiba industrial area (SIA) - State of Kuwait". Thesis, University of Bath, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267351.

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46

Surchamp, Alexia. "Emissions potentielles de polluants organiques persistants à partir du milieu urbain et par les activités de traitement des déchets : impact sur la qualité de l'air au voisinage des sources". Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066010/document.

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L’objectif a été de caractériser les émissions indirectes de composés organiques semi-volatils (PCB, HCB, PeCB, HAP, phtalates et PBDE) au droit de milieux potentiellement contaminés par leurs emplois (zones ferroviaires souterraines, axes de circulation) et de sites de traitement de déchets (station d’épuration, élimination, destruction de véhicules hors d’usage). Des réseaux de mesure comprenant des préleveurs d’air actifs « grand volume », des capteurs passifs et des bio-accumulateurs ont été utilisés pour acquérir des données au voisinage des sources potentielles. Les résultats révèlent une ubiquité de tous les composés recherchés dans l’air, où leurs présences en phase gazeuse est majoritaire. La contamination de l’air au niveau des sites d'étude montre une hiérarchisation commune (phtalates>HAP>HCB>PeCB>PCB>PBDE), où la contamination de l’air en période estivale est plus importante, confirmant l’importance relative des émissions diffuses par volatilisation passive. Les résultats obtenus à partir des capteurs passifs démontrent l’intérêt de cet outil complémentaire pour la réalisation d’études à grande échelle spatio-temporelle. L’interprétation de l’état du milieu (IEM) à partir des analyses d’air, de sols, de retombées atmosphériques et de bio-accumulateurs végétaux, indiquent cependant que la contamination au voisinage de zones industrielles demeure le plus souvent du niveau de celle du milieu urbain dense. Les résultats révèlent que les émissions diffuses de COSV non halogénés (phtalates et HAP) par volatilisation passive, constituent un enjeu environnemental et sanitaire qui pourrait dépasser celui des anciens POP (PCB, PBDE)
The objective was to characterize the indirect emissions of SVOCs (PCB, HCB, PeCB, PAHs, phthalates and PBDE) on potentially contaminated environments by their uses (underground railway zones, traffic roads) and waste treatment sites (wastewater treatment plants, elimination, vehicle destruction sites). Measuring networks including "large volume" active air samplers, passive samplers and environmental bio-accumulators have been used to acquire data in the vicinity of potential sources. The results reveal an ubiquity of all the measured compounds in the air, where their presence in the gas phase prevails. The air contamination of the study sites shows a common ranking (phthalates> PAHs> HCB> PeCB> PCBs> PBDEs), where air contamination in summer is more important, confirming the relative importance of diffuse emissions by passive volatilization The results from passive sensors demonstrate the value of this complementary tool for the realization of large spatio-temporal scale study. The interpretation of environmental state from air, soil, atmospheric deposition and plant bio-accumulators analyzes indicates that the contamination remains mostly equivalent to urban area.. The results reveal that diffuse emissions of non-halogenated SVOCs (phthalates and PAHs) by passive volatilization, represent an environmental and health challenge where that could exceed those of past POPs (PCBs, PBDE, ...)
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47

Ren, Zhengen. "Enhanced modelling of indoor air flows, temperatures, pollutant emission and dispersion by nesting sub-zones within a multizone model". Thesis, Queen's University Belfast, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.269182.

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48

Villa, Tommaso Francesco. "Development of an unmanned aerial vehicle (UAV) system for in-situ characterization of combustion source emissions". Thesis, Queensland University of Technology, 2017. https://eprints.qut.edu.au/114062/2/Tommaso_Francesco_Villa_Thesis.pdf.

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This research developed an Unmanned Aerial Vehicle System for atmospheric pollution assessment, contributing new methodology and knowledge to the fields of air quality, human health and human exposure. This system was tested, validated and employed to characterize gaseous and particle pollutant concentration generated by traffic from a motorway in open space within the atmospheric column, and emitted from a ship while operating at sea, to develop ship emission factors. It allows measurements of air pollution under conditions where sampling with the existing techniques is not feasible or poses too high risk.
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49

Huang, Min. "A multi-scale modeling study of the impacts of transported pollutants and local emissions on summertime western US air quality". Diss., University of Iowa, 2012. https://ir.uiowa.edu/etd/2898.

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The impacts of transported and locally-produced pollutants on western US air quality during summer 2008 are studied using the multi-scale Sulfur Transport and Deposition Modeling system. Transported background (TBG) is an indicator of the influences from extra-regional emissions or the lower stratosphere. The magnitude of TBG is expected to increase as the emissions from international sources grow. This trend is especially important in the context of US air quality standards, which tend to become more stringent to protect human health and ecosystems. Forward sensitivity simulations in which the model boundary conditions and emissions are perturbed show that TBG strongly and extensively affect western US surface ozone (more than half of the total), compared to other contributors to background ozone (North American, NA, biomass burning, BB and biogenic emissions), and the impacts differ among various geographical regions and land types. The stratospheric ozone impacts are weak. The TBG ozone contributes most to western US ozone among all TBG species, and TBG peroxyacetyl nitrate is the most important species among ozone precursors. Compared to monthly mean 8-hour daily maximum ozone, the secondary standard metric "W126 monthly index" shows larger responses to TBG perturbations and stronger non-linearity to the size of perturbations. Overall the model-estimated TBG impacts negatively correlate to the vertical resolution and positively correlate to the horizontal resolution. The estimated TBG impacts weakly depend on the magnitude of uncertainties in the US anthropogenic emissions. The transport/subsidence processes that link airmasses aloft with the surface pollution level are analyzed by trajectories, time-lag correlation and adjoint sensitivity analyses. Various types of observations are used to identify source regions and transport processes, and to improve model prediction using the four-dimensional variational data assimilation during a long-range transport episode. The sectoral and geographical contributions to summertime US black carbon (BC) distributions are studied. NA emissions heavily (>70%) affect the BC levels from the surface to 5 km, while non-NA plumes compose more than half of the BC above 5 km. NA and non-NA BB, NA transportation and non-NA residential emissions are the major contributing sectors. Aircraft measurements during the California phase of the Arctic Research of the Composition of the Troposphere from Aircraft andSatellites (ARCTAS-CARB) field campaign show that BC/(organic matter + nitrate + sulfate) mass ratios fairly well represent BC's warming potential over southern California, which can be approximated by BC/(organic matter + sulfate) and BC/sulfate for plumes affected and unaffected by fires, respectively. The responses of BC/(organic matter + sulfate) and BC/sulfate to removing each emission sector indicate that mitigating NA transportation emissions has the highest potential for regional air quality and climate co-benefits. Contributions from NA BB and extra-regional emissions differ for summer and spring (April 2008).
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50

Wang, Linlin. "Inter-pollutant and reactivity-weighted air pollutant emission trading in Texas". Thesis, 2006. http://hdl.handle.net/2152/2651.

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