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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.
11

Time series regression modelling of air quality data in Hong Kong /

Yan Ka-lok. January 1900 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1994. / Includes bibliographical references (leaf 56).
12

A study of passive sampling and modelling techniques for urban air pollution determination /

Wong, Ming-hong, Daniel. January 1999 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1999. / Includes bibliographical references (leaves 97-99).
13

A study of suspended airborne particulates monitoring in Hong Kong /

Tong, Wai-fong. January 1997 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1997. / Includes bibliographical references (leaf 50-56).
14

Apportionment of air particulate sources in Hong Kong : development of sampling and analytical methods for the determination of organic and inorganic compounds /

Cheung, Ho-kwong. January 1996 (has links)
Thesis (Ph. D.)--University of Hong Kong, 1996. / Includes bibliographical references.
15

Using a radiative transfer model in conjunction with UV-MFRSR irradiance data for studying aerosols in El Paso-Juarez airshed

Medina Calderon, Richard. January 2009 (has links)
Thesis (M.S.)--University of Texas at El Paso, 2009. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.
16

Particulate modeling and control strategy for Atlanta, Georgia

Park, Sun-kyoung. January 2005 (has links)
Thesis (Ph. D.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2006. / Mulholland, James, Committee Member ; Bergin, Michael, Committee Member ; Russell, Armistead, Committee Chair ; Wang, Yuhang, Committee Member ; Nenes, Athanasios, Committee Member. Vita.
17

The study of volatile organic compounds in urban and indoor air

Clarkson, Paul Jonathan January 1998 (has links)
Chapter 1 is a review of the literature concerning the study of volatile organic compounds in the atmosphere. It examines the basic chemistry of the atmosphere and the roles that organic compounds play in it. Also investigated are the methods of sampling and analysing the volatile organic compounds in the air, paying particular attention to the role of solid phase sampling. Chapter 1 also examines the role of volatile organic compounds on air quality. Chapter 2 describes the experimental procedures that were employed during the course of this research project. Chapter 3 examines a multi-method approach to the study of volatile organic compounds in urban and indoor air. The methods employed were capillary electrophoresis, high performance liquid chromatography and gas chromatography. Although good results were obtained for the various methods that were investigated Chapter 3 concludes that a more unified analytical approach is needed to the study of the air. Chapter 4 investigates the possibilities of using a unified approach to the study of VOC's. This is achieved by the development of an air sampling method that uses solid phase extraction cartridges. By investigating many aspects of air sampling mechanisms the results show that a simple yet efficient method for the sampling of VOC in air has been developed. The SPE method is a reusable, yet reliable method that by using sequential solvent desorption has been shown to exhibit some degree of selectivity. The solid phase that gave the best results was styrene-divinyl benzene however other phases were also investigated. The use of a single gas chromatography method was also investigated for the purpose of confirmatory identification of the VOC's. Various detection systems were used including MS and AED. It was shown that by optimising the GC's it was possible to get complimentary results. Also investigated was the possibility of compound tagging in an attempt to confirm the identity of several of the compounds found in the air. Chapter 5 is a theoretical discussion of the ways presenting the data obtained experimentally in an easy to understand way. Instead of targeting 7 or 8 compounds as being representative of air quality it is argued that by using a technique such as Air Fingerprinting, it is possible to show data that is indicative of the whole air sample. Using actual data it is possible to show the origin of the air sample in a simple yet effective way using air fingerprints. Also discussed is the Individual Component Air Quality Index, this is a method of quantifying air quality. By taking into account compound toxicity, atmospheric lifetime and UV exposure, the ICAQI, it is argued, is a technique that presents a more accurate picture of air quality. Chapter 6 concludes the thesis by drawing together the themes and issues that were raised.
18

The use of charcoal cloth in passive sampling of the environment

Mann, Hardip Singh January 1991 (has links)
No description available.
19

Measurements of carbonaceous aerosol across the U.S. : sources and role in visibility degradation /

Shah, Jitendra J. January 1981 (has links)
Thesis (Ph. D.)--Oregon Graduate Center, 1981.
20

Modeling Air Quality Near Freeways Using a Three Dimensional Eulerian Model

Kota, Sri Harsha 2009 August 1900 (has links)
Near-road air quality studies have indicated the presence of high levels of pollutants. In this study, a three dimensional Eulerian model is developed which can be used to study the air quality near freeways. A vehicle-induced turbulence parameterization is included in the model to estimate better the turbulent diffusion of pollutants. The near-road air quality model is used to study two different cases. In the first case, the model is validated using the data from General Motor's SF6 dispersion experiment, conducted at Michigan in 1976. Sensitivity of the model to meteorology and traffic-related parameters are studied in detail. In the second case, the spatial distribution of ozone, carbon monoxide, NOx and 1,3-Butadiene near a simulated 8-lane freeway was studied. Model simulation for the first case yielded better results than US EPA's CALINE models which were previously used for regulatory purposes. Model performance when analyzed at different wind directions shows an overall good performance. The results also show that the model performs well at surface but slightly over predicts pollutant concentration at higher elevations. The simulation results for second case at different directions of wind and at different boundary conditions for model species, places emphasis on the importance of the inclusion of the chemical mechanism in the study of near-road air quality.

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