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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.
261

Measurement and analysis of ambient atmospheric particulate matter in urban and remote environments

Hagler, Gayle S. W. 09 May 2007 (has links)
Atmospheric particulate matter pollution is a challenging environmental concern in both urban and remote locations worldwide. It is intrinsically difficult to control, given numerous anthropogenic and natural sources (e.g. fossil fuel combustion, biomass burning, dust, and seaspray) and atmospheric transport up to thousands of kilometers after production. In urban regions, fine particulate matter (particles with diameters under 2.5 m) is of special concern for its ability to penetrate the human respiratory system and threaten cardiopulmonary health. A second major impact area is climate, with particulate matter altering Earth s radiative balance through scattering and absorbing solar radiation, modifying cloud properties, and reducing surface reflectivity after deposition in snow-covered regions. While atmospheric particulate matter has been generally well-characterized in populated areas of developed countries, particulate pollution in developing nations and remote regions is relatively unexplored. This thesis characterizes atmospheric particulate matter in locations that represent the extreme ends of the spectrum in terms of air pollution the rapidly-developing and heavily populated Pearl River Delta Region of China, the pristine and climate-sensitive Greenland Ice Sheet, and a remote site in the Colorado Rocky Mountains. In China, fine particles were studied through a year-long field campaign at seven sites surrounding the Pearl River Delta. Fine particulate matter was analyzed for chemical composition, regional variation, and meteorological impacts. On the Greenland Ice Sheet and in the Colorado Rocky Mountains, the carbonaceous fraction (organic and elemental carbon) of particulate matter was studied in the atmosphere and snow pack. Analyses included quantifying particulate chemical and optical properties, assessing atmospheric transport, and evaluating post-depositional processing of carbonaceous species in snow.
262

The Kaohsiung Siaogang Residents¡¦ Environmental Perception

Liu, Chun-Hsiu 26 July 2012 (has links)
Cognition, attitudes, behavior and feel things from the environment to explore the small Port of Kaohsiung residents in the air pollution control fee levied in the Republic of China 87 years, for housing the regional air pollution perception of air quality to improve satisfaction and surfacetake the behavior of the current situation of air pollution.To explore the residents of different backgrounds, perception, the air pollution and air quality to improve the satisfaction and take the differences of behavior. This study used a random convenience sampling questionnaire, collection of air pollution fee on air quality questionnaire "to refer to the relevant literature and experts to discuss the small port area residents as a research tool.In this study, questionnaire survey was small Port of Kaohsiung residents to random convenience sampling survey, issued 233 questionnaires were valid questionnaires was 212. Finally, the collected data using descriptive statistics, independent sample t test, one-way ANOVA, Pearson correlation analysis and simple regression and other statistical methods, data processing analysis. The results of this study found that the small port area residents are the upper level air pollution Perception extent. However, a small port area residents as both are not satisfied with the degree of satisfaction for today's small port area of air quality improvement.Acts taken in the face of air pollution is mostly self-protection, and group behavior, and petition the face of lack of government subsidies, while complaints. The results showed that although the high degree of Perception of the small port area residents air pollution, but taken in the face of air pollution, but a means of self-protection, so this study will analyze relevant statistical data and the last suggestions reference, and more availableinformation for the government to improve air quality.
263

Improving aerosol simulations: assessing and improving emissions and secondary organic aerosol formation in air quality modeling

Baek, Jaemeen 21 August 2009 (has links)
Both long-term and short-term exposure to fine particulate matter (PM2.5) has been shown to increase the rate of respiratory and cardiovascular illness, premature death, and hospital admissions from respiratory causes. It is important to understand what contributes to ambient PM2.5 level to establish effective regulation, and air quality model can provide guidance based on the best scientific understanding available. However, PM2.5 simulations in air quality models have often found performance less than desirable, particularly for organic carbon levels. Here, some of major shortcomings of current air quality model will be addressed and improved by using CMAQ, receptor models, and regression analysis. Detailed source apportionment of PM2.5 performed using the CMAQ-tracer method suggests that wood combustion and mobile sources are the largest sources of PM2.5, followed by meat cooking and industrial processes. Biases in emission estimates are investigated using tracer species, such as organic molecular markers and trace metals that are used in receptor models. Comparison of simulated and observed tracer species shows some consistent discrepancies, which enables us to quantify biases in emissions and improve CMAQ simulations. Secondary organic aerosol (SOA) is another topic that is investigated. CMAQ studies on organic aerosol usually underestimate organic carbon with larger than a 50% bias. Formation of aged aerosol from multigenerational semi-volatile organic carbon is added to CMAQ, significantly improving performance of organic aerosol simulations.
264

Characterizing the photochemical environment over China

Liu, Zhen 30 March 2012 (has links)
The rapid rising anthropogenic emissions driven by economic growth over China documented by satellite observations and bottom-up inventories have led to severely degraded air quality, and also have been suggested to be linked to the recent upward trends of tropospheric O₃ over the regions downwind of China. Multi-scale modeling analyses facilitated by ground-level, aircraft and satellite observations have been conducted to understand the atmospheric chemistry over China. Analyses using a 1-D photochemical model constrained by measurements at Beijing in August of 2007 suggest that reactive aromatic VOCs are the major source (~75%) of peroxy acetyl nitrate (PAN). Detailed radical budget analyses reveal the very fast ROₓ (OH + HO₂ + RO₂) production, recycling and destruction driven by VOC oxidation and heterogeneous processes. Photoenhanced aerosol surface uptake of NO₂ is found to be the predominant source of nitrous acid (HONO) during daytime (~70%). 3-D regional modeling analyses of tropospheric vertical column densities of glyoxal (CHOCHO) from SCIAMACHY show that anthropogenic emissions of aromatic VOCs are substantially underestimated (by a factor of 5 - 6, regionally varied) over China. Such an underestimation is the main cause of a large missing source of CHOCHO over the region in current global models, and could also partly explain the underestimation of organic aerosols in previous modeling studies.
265

Evaluating Hong Kong's air pollution legislation and policies

Wong, Ping-hei, Benny, 黃丙熙 January 2014 (has links)
Air pollution is a major environmental problem that poses numerous health risks to those exposed to it. The adverse health effects are compounded in a place as dense as Hong Kong and further intensified due to its proximity to industrial and manufacturing plants across the border in Mainland China. Hong Kong has attempted to address the issue of air pollution through the enactment of legislation and policies such as the 1983 Air Pollution Control Ordinance and Air Quality Objectives, but so far these measures have not proven to be particularly effective. The new Air Quality Objectives are not as stringent as claimed by the Environmental Protection Department, the legal system is limited in enforcing air pollution legislation, and the Air Pollution Control Ordinance itself is flawed at best and requires urgent attention. An examination of the air pollution legislation and policies of overseas jurisdictions such as Ontario, California, and Tokyo show that these regions have made significant progress in addressing air pollution by prioritizing public health and utilizing a variety of measures to reduce air pollution. Ontario’s Environmental Protection Act gives the Ministry of the Environment numerous ways to deal with polluters and the Environmental Bill of Rights helps facilitate public participation in environmental decision-making by granting the public the right to apply for an investigation or review of existing legislation and policies. California’s Air Resources Board has been commended for enacting air pollution regulations that are more stringent than national standards and many states have adopted the Golden State’s standards as their own. In Japan, government, corporate, and public responsibilities for reducing air pollution and protecting the environmental are outlined in the Basic Environmental Law. Legislation providing compensation to victims of pollution as well as the use of a Total Mass Emissions Control system has helped the country achieve an extraordinary rate of compliance with national air quality standards. By studying, modifying and applying air pollution control legislation and policies being used in the three jurisdictions to its own Air Pollution Control Ordinance and air pollution control management as a whole, Hong Kong can be better prepared to protect public health and it’s environment in the future. / published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
266

Large eddy simulations of wind flow and pollution dispersion in an urban street canyon

So, Shuk-pan, Ellen., 蘇淑彬. January 2003 (has links)
published_or_final_version / abstract / toc / Mechanical Engineering / Master / Master of Philosophy
267

The characterization of particulate pollutants in southern Arizona: the historical data base and field study

Linak, William Patrick January 1980 (has links)
No description available.
268

Dimensions of air pollution policies among the American states, 1967-1970

Nelson, Peter Evan, 1944- January 1974 (has links)
No description available.
269

Cadmium content in sphalerites, copper ores, soils and plants in southern Arizona

Kresan, Peter Lawrence, 1948- January 1975 (has links)
No description available.
270

AIR POLLUTION PARTICULATE MAPPING

Longley-Cook, Barbara Ann Norman, 1942- January 1971 (has links)
No description available.

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