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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
641

Co-Benefits of Global and Domestic Greenhouse Gas Emissions for Air Quality and Human Health

Jason West, J., Zhang, Yuqiang, Smith, Steven J., Silva, Raquel A., Bowden, Jared H., Naik, Vaishali, Li, Ying, Gilfillan, Dennis, Adelman, Zachariah, Fry, Meridith M., Anenberg, Susan C., Horowitz, Larry, Lamarque, Jean Francois 01 January 2017 (has links)
Most co-benefits studies have been conducted on local or national scales. However, we find that for a coordinated international GHG reduction, much of the air quality and health benefits come from GHG reductions in foreign nations. This is particularly true for ozone, which has a longer atmospheric lifetime than PM2.5, and which is affected by methane reductions. Together these findings show that co-benefits for air quality and health are greater when GHG reductions are coordinated with other nations. These results also show that previous co-benefits studies on local or national scale may significantly underestimate the total co-benefits by omitting i.) the benefits of domestic pollutant reductions for regions outside of the domain considered, and ii.) the benefits of foreign GHG reductions if the domestic reduction is coordinated with international action.
642

Retrieval of aerosol optical depth from MODIS data at 500 m resolution compared with ground measurement in the state of Indiana

Alhaj Mohamad, Fahed 05 May 2015 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Objective: "The purpose of this research is: Study the use of Moderate Resolution Imaging Spectroradiometer (MODIS) data in retrieving the aerosol optical depth (AOD) over Indiana State at high resolution of 500 meters. Examine the potential of using the resulted AOD data as an indicator of particulate air pollution by comparing the satellite derived AOD data with the ground measurements (provided from the continuous air monitors available over the study area). If an association should be found, AOD data would be used to map particulate matter (PM) concentration. Assess current and future ambient concentrations of air pollutants in the State of Indiana using the AOD."
643

The use of AERMOD for CAL3QHC applications

Fan, Jiwen 01 April 2002 (has links)
No description available.
644

Assessment of environmental exposure to air pollution within four neighbourhoods of the Western Cape, South Africa

Madonsela, Benett Siyabonga January 2019 (has links)
Thesis (MTech (Environmental Health))--Cape Peninsula University of Technology, 2019. / Background: A recent review on the effects of ambient air pollution on human health in sub-Saharan Africa, specifically calls for an urgent need for more epidemiological studies in developing countries due to a lack of data in these countries. Air pollution information on exposure is important for understanding and addressing its public health impact in developing countries. In many African countries, the spatial distribution of air pollutants has not been quantified even though air pollution is a global public health risk. The main goal of the study was to quantify and compare the seasonal spatial variation of household air pollution in the 4 Western Cape neighbourhoods. Methods: Weekly indoor and outdoor measurements of Particulate Matter (PM2.5), Sulphur dioxide (SO2), Ozone (O3), Carbon monoxide (CO) and Nitrogen dioxide (NO2) were conducted at 127 households in four informal settlement areas (Khayelitsha, Marconi-Beam, Masiphumulele and Oudtshoorn) during one month each in summer and winter. PM2.5 measurements were conducted using Mesa Labs GK2.05 (KTL) cyclone with the GilAir Plus Air Sampling Pump, Gases were measured using Passam passive samplers. Statistical analyses were performed using Stata V12. Simple linear regression was used to evaluate the relationship between continuous exposure levels and the respective predictor variables. These include distance to major roads, bus routes, open grills and waste burning sites. Results: The highest average weekly outdoor PM2.5 and NO2 concentrations for summer were recorded in Milnerton (8.76 µg/m3 and 16.32 µg/m3 respectively). However, the highest average concentrations during winter for PM2.5 were recorded in Oudtshoorn (PM2.5: 16.07 µg/m3), whilst the highest NO2, was recorded in Khayelitsha (NO2: 35.69 µg/m3). SO2 levels were consistently low during both seasons. Noordhoek generally recorded the lowest average levels for all pollutants. Winter average weekly concentrations were generally higher than the levels recorded in summer for all pollutants. In a sub-sample of indoor and outdoor measurements, the results were comparable for PM2.5, NO2 and CO. However, the results of Ozone (O3) showed relatively higher (~10 times) outdoor compared to indoor levels. Linear regression modelling results revealed that significant predictors of elevated exposure to PM2.5 were proximity to construction activities and open grills. Analysis demonstrated a clear dose-response relationship with distance, with open grills within 1000m associated with a 0.33 µg/m3 increase in PM2.5 to 6.77 µg/m3 at a distance of 25 meters. Results from the linear regression modelling revealed that significant predictors of exposure to NO2 were proximity to rapid transport bus stops, bus routes, taxi routes and major routes. Distance to rapid transport bus stops demonstrated an increase in NO2 between 0.09 µg/m3 (at 1km) to 2.16 µg/m3 (at 50m) during summer. A similar pattern was observed for taxi routes and bus routes displaying an increase of 6.26 μg/m3and 6.82 μg/m3 respectively within the proximity of 1000 meters. / MAUERBERGER Foundation Scholarship
645

Perception of air pollution and its impact on human health in the south urban basin : a community perspective

Vissers, Amanda 11 1900 (has links)
Recent and past events in the South Durban Basin (SDB) have highlighted the possible connection between perceived air pollution concerns and deteriorating health. The aim of this study is to explore how the SDB community perceives air pollution and if this can be related to some of the health problems that are experienced in these communities. The ultimate aim is to determine whether the respondents connect air pollution to specific illnesses and also how they perceive the actions used to combat air pollution and its negative health impacts. This information is gathered through a questionnaire conducted in various study areas both within and outside the SDB, then compared with demographic variables. This is done to determine if perception is related to direct industrial activity or if there are other factors influencing results. Variables such as race and level of education had little impact on the results. The results showed that areas within the SDB experience a high neighborhood satisfaction despite the current general belief of air pollution being connected to ill health. The control areas outside of the SDB support theories of gender and race and its relationship to air pollution, currently presented by researchers in the perception field. Strong associations’ do exist between general environmental satisfaction and gender. Perception of current legal enforcement is exerting a strong effect on air pollution perception formation. Vitally important is the connection of daily concrete experiences of air pollution with the lack of transparency and communication between industry and communities. It is resulting in the current perception of illness being connected to tangible air pollution. The aim is to further future studies on establishing links between health and air quality. Gaining insight from the study of public risk perceptions based on local knowledge and experience in particular places, will help shape the role of environmental policy and management response systems. / Geography / M.A. (Geography)
646

Air pollution and respiratory disease incidence of Guangzhou: a study of spatial interpolation methodsusing GIS, 2003-2004

Yu, Peng, 于朋 January 2008 (has links)
published_or_final_version / Geography / Master / Master of Philosophy
647

The biomonitoring of heavy metal pollution in the wood and leaf chemistry of urban trees in Hong Kong

Ho, Ching-yee, Christina., 何靜宜. January 1999 (has links)
published_or_final_version / Geography and Geology / Master / Master of Philosophy
648

Právní regulace ochrany před znečišťováním z mobilních zdrojů / Legal regulation of protection against pollution from mobile sources

Ottomanský, Miroslav January 2012 (has links)
Miroslav Ottomansky Legal regulation of protection against air pollution from mobile sources The goal of this thesis is to map tools used for legal regulations of mobile pollution sources. Thesis focuses on problematic regulation of motor vehicles' pollution in Czech Republic, however it also outlines basic legal adjustements related to other mobile pollution sources. Thesis starts with basic introduction to this problematic followed by overview of international legal regulations and main conceptional tools used for legal regulations in European Union. In the chapter dedicated to the principles of european law in terms of regulation of mobile sources' pollution thesis tries to research how are those regulations already being applied to specific legal norms. One chapter is dedicated to protection of rights for convenient environment and their prosecution. In the next part of the thesis the normative regulations within emission standarts, approval of types, requirements for fuel quality and control of emissions of motor vehicles are examined. In the last chapter the new legal adjustment of mobile sources' pollution named in the law of enviroment protection is briefly explained in context with increasing number of problems with regulation of road traffic in cities. Key words: air pollution from mobile sources,...
649

Viabilidade e importância da redução da emissão de clorofluorcarbonos (CFCS) por reciclagem e controle no uso / Feasibility and importance of reducing emissions of chlorofluorocarbons (CFCs) for recycling and control in use

Assunção, João Vicente de 06 July 1993 (has links)
Uma pesquisa de campo foi conduzida para verificar as condições reais de utilização de clorofluorcarbonos em sistemas de refrigeração e de condicionamento de ar. A pesquisa cobriu os setores de refrigeração de supermercados, ar condicionado de edifícios e oficinas de reparação e de manutenção de geladeiras, \"Freezers\" e condicionadores de ar compactos e automotivos. A região escolhida para a pesquisa está localizada no município de São Paulo, tendo uma superfície de 12,504 Km2. As seguintes conclusões principais resultaram deste estudo: Predomina o consumo do HCFC 22 nos usuários pesquisados; a reciclagem e a recuperação ocorrem em pequena escala na região estudada; os sistemas de condicionamento de ar automotivos são a fonte mais significativa de substâncias agressivas à camada de ozônio, nos usuários pesquisados; vazamentos ocorrem por práticas de serviço não adequadas; a utilização do CFC 11 para limpeza de circuitos reduz o ganho obtido em sistemas que empregam o HCFC 22; a manutenção preventiva mostrou ser eficaz tanto para reduzir o consumo de gás refrigerante, como para reduzir a substituição de peças e componentes; a reciclagem e a recuperação do gás refrigerante tem efeito positivo em relação à camada de ozônio, economiza recursos naturais, reduz o consumo de energia, os riscos ao meio ambiente e à saúde da comunidade em geral. Finalmente, são feitas recomendações para o estabelecimento de um programa efetivo de reciclagem e recuperação de gases refrigerantes. / A field study was performed for verifying the actual conditions of the use of chlorofluorcarbons in refrigeration and air conditioning systems. The study has covered the sectors of supermarket refrigeration, building air conditioning systems, and refrigerators freezers and compact and automobile air conditioning systems repair shops. The region chosen for this study is located in the city of Sao Paulo and it has an area of 12.504 km2. The following conclusions resulted from the study: There is a predominance of the of HCFC 22 in the systems surveyied; recycling and recuperation are used in small scale in the region of the study; in the users covered by the study, the automobile air conditioning sector is the most important source of emission of ozone depleting substances; leaks occur because of bad service practices; the use of CFC 11 for circuit cleaning decreases the the gain obtained with the use of HCFC 22; the preventive maintenance has proved to be very efficient both for reducing the consum of refrigeration gases and for reducing the consum of parts and components of the refrigeration system; recycling and recuperation of refrigeration gases have positive effects in relation to the ozone layer, it saves natural resources, and reduces the risk to the enviromnent and to the public health. Finally, recommendations are made for the establishment of an effective refrigerant conservation program.
650

Viabilidade e importância da redução da emissão de clorofluorcarbonos (CFCS) por reciclagem e controle no uso / Feasibility and importance of reducing emissions of chlorofluorocarbons (CFCs) for recycling and control in use

João Vicente de Assunção 06 July 1993 (has links)
Uma pesquisa de campo foi conduzida para verificar as condições reais de utilização de clorofluorcarbonos em sistemas de refrigeração e de condicionamento de ar. A pesquisa cobriu os setores de refrigeração de supermercados, ar condicionado de edifícios e oficinas de reparação e de manutenção de geladeiras, \"Freezers\" e condicionadores de ar compactos e automotivos. A região escolhida para a pesquisa está localizada no município de São Paulo, tendo uma superfície de 12,504 Km2. As seguintes conclusões principais resultaram deste estudo: Predomina o consumo do HCFC 22 nos usuários pesquisados; a reciclagem e a recuperação ocorrem em pequena escala na região estudada; os sistemas de condicionamento de ar automotivos são a fonte mais significativa de substâncias agressivas à camada de ozônio, nos usuários pesquisados; vazamentos ocorrem por práticas de serviço não adequadas; a utilização do CFC 11 para limpeza de circuitos reduz o ganho obtido em sistemas que empregam o HCFC 22; a manutenção preventiva mostrou ser eficaz tanto para reduzir o consumo de gás refrigerante, como para reduzir a substituição de peças e componentes; a reciclagem e a recuperação do gás refrigerante tem efeito positivo em relação à camada de ozônio, economiza recursos naturais, reduz o consumo de energia, os riscos ao meio ambiente e à saúde da comunidade em geral. Finalmente, são feitas recomendações para o estabelecimento de um programa efetivo de reciclagem e recuperação de gases refrigerantes. / A field study was performed for verifying the actual conditions of the use of chlorofluorcarbons in refrigeration and air conditioning systems. The study has covered the sectors of supermarket refrigeration, building air conditioning systems, and refrigerators freezers and compact and automobile air conditioning systems repair shops. The region chosen for this study is located in the city of Sao Paulo and it has an area of 12.504 km2. The following conclusions resulted from the study: There is a predominance of the of HCFC 22 in the systems surveyied; recycling and recuperation are used in small scale in the region of the study; in the users covered by the study, the automobile air conditioning sector is the most important source of emission of ozone depleting substances; leaks occur because of bad service practices; the use of CFC 11 for circuit cleaning decreases the the gain obtained with the use of HCFC 22; the preventive maintenance has proved to be very efficient both for reducing the consum of refrigeration gases and for reducing the consum of parts and components of the refrigeration system; recycling and recuperation of refrigeration gases have positive effects in relation to the ozone layer, it saves natural resources, and reduces the risk to the enviromnent and to the public health. Finally, recommendations are made for the establishment of an effective refrigerant conservation program.

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