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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.
291

Assessment of airborne lead sources in Hong Kong using stable lead isotopic ratios.

January 2001 (has links)
Poon Lok-man. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 126-128). / Abstracts in English and Chinese. / ABSTRACT --- p.ii / ACKNOWLEDGEMENT --- p.v / LIST OF TABLES --- p.vi / LIST OF FIGURES --- p.vii / GLOSSARY --- p.viii / Chapter CHAPTER 1: --- INTRODUCTION --- p.1 / Chapter CHAPTER 2: --- AIR POLLUTANTS AND ENVIRONMENTAL MONITORING --- p.8 / Chapter CHAPTER 3: --- PRINCIPLE OF LEAD FINGERPRINTING --- p.15 / Chapter CHAPTER 4: --- INSTRUMENTATION AND THEORY --- p.20 / Chapter CHAPTER 5: --- OPTIMIZATION OF ANALYTICAL PERFORMANCE IN LEAD ISOTOPE ANALYSIS --- p.29 / Chapter CHAPTER 6: --- DETERMINATION OF LEAD CONTENTS AND ISOTOPIC RATIOS IN POTENTIAL AIRBORNE LEAD SOURCES --- p.55 / Chapter CHAPTER 7: --- DETERMINATION OF LEAD CONTENT IN PARTICULATES COLLECTED ONTO HV-FILTERS --- p.69 / Chapter CHAPTER 8: --- ENVIRONMENTAL SURVEY --- p.74 / Chapter CHAPTER 9: --- "CONCLUSIONS, LIMITATIONS AND FURTHER DIRECTION" --- p.97 / APPENDICES --- p.105 / BIBLIOGRAPHY --- p.126
292

A socio-economic and spatial investigation into the health implications of air pollution in Richards Bay, KwaZulu-Natal, South Africa.

Jaggernath, Jyotikumarie. January 2013 (has links)
There is increasing recognition of the links between air pollution and human health. Epidemiological studies have shown that there are numerous air pollutants that are associated with indoor energy use and with the production processes of industries, and most represent some sort of health implication. However, in-depth and fundamental knowledge of the health impact relationship of most pollutants is limited. This research evaluates the socio-economic and spatial aspects of the health implications of air pollution in Richards Bay (located 200 km north of Durban), KwaZulu-Natal. The research explores community perceptions and complaints relating to human health impacts emanating from air pollution in Richards Bay. The research is informed by a multi-conceptual framework (political economy incorporating political ecology, place perspectives and environmental justice) which influenced the methods chosen in conducting the research. Standard quantitative and qualitative methods were employed in the study to generate data relating to the research objectives. The process of triangulation which is the use of multiple methods that cuts across the qualitativequantitative divide was used. The various sources of information validate and clarify data by deepening and widening an understanding of the main issues under examination. The research was implemented in various communities in Richards Bay that reflect socioeconomic differences, which contributes significantly to ascertain whether health impacts are differentially experienced by different socio-economic groups. Furthermore, the research cross-tabulated experiences, perceptions and coping strategies of different socio-economic groups in the area, especially in relation to upper, middle and lower income clusters. The spatial aspect of the research (mapping of key social and health variables) is a major contribution of this research, which draws from the field of medical geography. Information on the main residential areas was illicitied from documents providing background details on Richards Bay. A purposive sampling approach was adopted to identify the seven communities, namely, Alton, Aquadene/ Brackenham, Arboretum, Meer-en-See, Empangeni Rail, Nseleni and Umhlathuze. Simple random point sampling was used to identify the households within the communities. The number of households in each community was determined using proportionate sampling. Four hundred and seventy nine housholds (479) were interviewed which was deemed to be a statistically relevant sampling size at a 95% confidence level. The study findings indicate that the lower income areas (Nseleni, Empangeni Rail and Umhlathuze) and the middle income areas (Aquadene/ Brackenham and Arboretum) have a more youthful population with a significant number being children, while the upper income areas (Alton and Meer en See) have a more elderly population. A similar trend was also found in relation to household size. There are clearly major variations in household income and employment types in Richards Bay, linked in part to the geographical location of communities based on economic and racial groups. Lower earning respondents were located mostly in the lower status areas which were classified as predominantly African populated areas as per the historical race classification and apartheid segregated areas. More than half of the respondents indicated that industrial smoke was the cause of their present health conditions. Other stated reasons were wide ranging and therefore there was no discernible pattern that emerged in relation to the causes for poor health experienced by the affected household member. However, the data did show that more respondents living in middle/ upper income areas identified causes. Reported health conditions include allergies (30.9%), coughing (29.8%), wheezing (25.5%), chest pains (18.4%) and asthmatic bronchitis/ asthma (17.7%). With regards to health care, the findings from the study show that the economically better off communities (Alton, Aquadene/ Brackenham, Arboretum and Meer en See) used the private, more expensive health care sector while generally households in lower income areas tend to rely on public or traditional health care facilities. An interesting finding was that most respondents rate their general health status as either excellent, good (more respondents from the middle/ upper income areas than the lower income areas) or satisfactory (more respondents from Umhlathuze). A large majority of the respondents reported air pollution as the main problem that is associated with industries in Richards Bay while the health impacts of pollutants from the industries manufacturing processes was the second main cause. The areas deemed to be the most polluted were generally in or in close proximity to the industrial area or the port area. Lower income areas tendered to be most polluted, according to respondents residing in these areas or who lived in similar low income areas. The majority of respondents were found to be living in dwellings/ households made from dwellings constructed with brick and asbestos, brick and zinc, stone and other traditional materials which is indicative of housing in the poorer communities who live in informal dwellings/ households and may be a causal contributing factor of the poor health status of these communities. The participatory mapping exercise conducted during the focus group discussion revealed that participants identified the industrial areas (including the port and surrounds) as the most polluted areas. Areas outside Richards Bay were considered to be the least polluted areas. The research findings indicate that there are a complex mix of socio-economic, environmental and spatial dynamics that influence air pollution and health impacts. Thus, health issues in the context of widespread air pollution concerns are linked to social, political and environmental aspects that require urgent attention. Air pollution and health impacts remain major concerns in many parts of the world, especially in areas of high levels of industrial development such as Richards Bay. The results of this research, therefore supports the findings of other researchers who reveal that communities/ neighborhoods of lower income status are most likely to bear the brunt of negative impacts and that air pollution from indoor uses of energy, behavioral factors such as cigarette smoking and industrial processes contribute to an individual’s/ community’s quality of life. / Thesis (Ph.D.)-University of KwaZulu-Natal, Durban, 2013.
293

Development of policies to ameliorate the environmental impact of cars in Perth City, using the results of a stated preference survey and air pollution modelling

Siddique, Sharif Rayhan January 2007 (has links)
[Truncated abstract] Air pollution is increasingly perceived to be a serious intangible threat to humanity, with air quality continuing to deteriorate in most urban areas. The main sources of inner city pollution are motor vehicles, which generate emissions from the tail pipe as well as by evaporation. These contain toxic gaseous components which have adverse health effects. The major components are carbon monoxide (CO), nitrogen dioxide (NO2), nitric oxide (NO), sulphur dioxide (SO2), particulates (PM10), and volatile organic compounds (VOC). CO and oxides of nitrogen (NOx) are major emissions from cars. This study focuses on pollutant concentration in Perth city and has sought to develop measures to improve air quality. To estimate concentrations, the study develops air pollution models for CO and NOx; on the basis of the model estimates, effective policy is devised to improve the air quality by managing travel to the city. Two peaks, due to traffic, are observed in hourly CO and NOx concentrations. Unlike traffic, however, the morning peak does not reach the level of the afternoon peak. The reasons for this divergence are assessed and quantified. Separate causal models of hourly concentrations of CO and NOx explain their fluctuations accurately. They take account of the complex effects of the urban street canyon and winds in the city. The angle of incidence of the wind has significant impact on pollution level; a wind flow from the south-west increases pollution and wind from the north-east decreases it. The models have been shown to be equivalent to engineering and scientific models in estimating emission rate in the context of street canyons. However the study models are much more precise in the Perth context. ... The models are used to calculate the marginal effects for all attributes and elasticity for fuel price. In almost all attributes the non-work group is more responsive than the work group. Finally, the SP model results are integrated into an econometric model for the purpose of prediction. The travel behaviour prediction is used to estimate the policy impact on air quality. The benefit from the air quality improvement is reported in terms of life saved. The estimated relationships between probability of death and air pollution determines the number of lives that could be saved under various policy scenarios. A ratio of benefits to the financial and perceived sacrifices by drivers is calculated to compare the effectiveness of the suggested policies. A car size charge policy was found to be the most cost effective measure to ameliorate the environmental impact of cars in Perth, with a morning peak entry time charge being almost as cost effective. The study demonstrates the need for appropriate modelling of air pollution and travel behaviour. It brings together analytical methods at three levels of causality, vehicle to air pollution, charge to travel response, and air pollution to health.
294

A SPECTROPOLARIMETER FOR THE ANALYSIS OF ATMOSPHERIC AEROSOLS.

Elkins, William Patrick. January 1983 (has links)
No description available.
295

Baseline assessment of the density and diversity of birds around Matimba and Medupi power station / Luckson Muyemeki

Muyemeki, Luckson January 2015 (has links)
Bird populations are changing at unprecedented rates in response to human-induced changes to the global environment, and these rates of change are expected to accelerate over the coming decades. Changes in the levels of sulphur dioxide (SO2) in the atmosphere through emissions from power stations pose a potential threat to bird populations. However, avian response to SO2 pollution is poorly understood. Exploring the relationship between avian diversity and SO2 exposure levels will help in determining species sensitive to air pollution. This study seeks to understand the interactions between avian diversity and SO2 concentration levels around Matimba power station so as to have more insight on the level of avian vulnerability to air pollution. Matimba is an important site in South Africa as a second coal fired power station, Medupi, is currently being constructed with additional stations also a possibility. This study represents an important baseline assessment of the avian population status before the additional pollution burden is realised from Medupi. Ten min repeated point counts were conducted at three sample sites with varying distances from Matimba and Medupi power stations. These counts were used to calculate bird species density and diversity. Cloud-free Landsat 8 imagery acquired on 7 January, 2014 was used to derive habitat structure and productivity variables. Elevation variables were derived using a DEM (Digital Elevation Model) obtained from NASA Global Data Explorer. The AERMOD dispersion model was used to characterise spatio-temporal variations in ambient SO2 concentrations around Matimba power station. Multiple regression analysis was then used to ascertain which of these variables (SO2, habitat structure, productivity and terrain) contribute most to the observed variation in bird species density and diversity around Matimba and Medupi power stations. SO2 polluted air did not have an influence on bird species density and diversity at the community level. At species level two species (Batis molitor and Streptopelia senegalensis) exhibited some measure of negative response to SO2 air pollution. However, after further investigation using multiple regression analysis it was revealed that habitat structure had more influence on the density of these two species compared with ambient SO2 concentrations. Bird species density and diversity varied significantly among the sample sites but were not related to the distance to the source of the SO2 air pollution. Evidence obtained from this study revealed that continuous monitoring of the interactions between SO2 polluted air and bird populations is recommended for a more comprehensive understanding of avian susceptibility towards SO2 air pollution and this will also facilitate in the selection of sensitive and relevant species for future ecology studies at other coal-fired power stations. Furthermore, it is expected that SO2 concentrations will significantly increase with the commissioning of Medupi power station thus further necessitating the need for continuous monitoring of bird species densities around Matimba and Medupi power stations. / MSc (Geography and Environmental Management), North-West University, Potchefstroom Campus, 2015
296

Baseline assessment of the density and diversity of birds around Matimba and Medupi power station / Luckson Muyemeki

Muyemeki, Luckson January 2015 (has links)
Bird populations are changing at unprecedented rates in response to human-induced changes to the global environment, and these rates of change are expected to accelerate over the coming decades. Changes in the levels of sulphur dioxide (SO2) in the atmosphere through emissions from power stations pose a potential threat to bird populations. However, avian response to SO2 pollution is poorly understood. Exploring the relationship between avian diversity and SO2 exposure levels will help in determining species sensitive to air pollution. This study seeks to understand the interactions between avian diversity and SO2 concentration levels around Matimba power station so as to have more insight on the level of avian vulnerability to air pollution. Matimba is an important site in South Africa as a second coal fired power station, Medupi, is currently being constructed with additional stations also a possibility. This study represents an important baseline assessment of the avian population status before the additional pollution burden is realised from Medupi. Ten min repeated point counts were conducted at three sample sites with varying distances from Matimba and Medupi power stations. These counts were used to calculate bird species density and diversity. Cloud-free Landsat 8 imagery acquired on 7 January, 2014 was used to derive habitat structure and productivity variables. Elevation variables were derived using a DEM (Digital Elevation Model) obtained from NASA Global Data Explorer. The AERMOD dispersion model was used to characterise spatio-temporal variations in ambient SO2 concentrations around Matimba power station. Multiple regression analysis was then used to ascertain which of these variables (SO2, habitat structure, productivity and terrain) contribute most to the observed variation in bird species density and diversity around Matimba and Medupi power stations. SO2 polluted air did not have an influence on bird species density and diversity at the community level. At species level two species (Batis molitor and Streptopelia senegalensis) exhibited some measure of negative response to SO2 air pollution. However, after further investigation using multiple regression analysis it was revealed that habitat structure had more influence on the density of these two species compared with ambient SO2 concentrations. Bird species density and diversity varied significantly among the sample sites but were not related to the distance to the source of the SO2 air pollution. Evidence obtained from this study revealed that continuous monitoring of the interactions between SO2 polluted air and bird populations is recommended for a more comprehensive understanding of avian susceptibility towards SO2 air pollution and this will also facilitate in the selection of sensitive and relevant species for future ecology studies at other coal-fired power stations. Furthermore, it is expected that SO2 concentrations will significantly increase with the commissioning of Medupi power station thus further necessitating the need for continuous monitoring of bird species densities around Matimba and Medupi power stations. / MSc (Geography and Environmental Management), North-West University, Potchefstroom Campus, 2015
297

An evaluation of meteorological data needs for urban pollution modelling

Arciszewska, C. January 2001 (has links)
Atmospheric dispersion models are being increasingly used by local authorities in the United Kingdom as part of their urban air quality management programmes. Output from dispersion models now forms a vital part of any environmental impact assessment, road improvement or traffic management scheme or environmental health study. This study is centred primarily on Northampton, a county town in Southern England and is concerned with the limitations of meteorological data available to local authorities. The first part of the study investigates the variation in certain key meteorological parameters both within Northampton and between synoptic stations up to 70 kilometres away. The second part examines modelling outcomes using different sets of meteorological data and evaluates the performance of an urban dispersion model in relation to monitored air quality data. Special emphasis is placed on the use of cloud cover as a meteorological input variable. A small case study of monitoring and modelling work carried out in the London Borough of Richmond is also presented
298

Air pollution in China: a study of public perception

Yan, Yihong January 1900 (has links)
Master of Regional and Community Planning / Department of Landscape Architecture/Regional and Community Planning / Brent Chamberlain / Air pollution is a serious health and environmental problem. In fact, poor air quality has been linked to numerous diseases and is a significant public health issue related to urban planning. These problems can be clearly seen in urban Chinese cities, most recently with the first ever Red Alert in Beijing China in 2015. In 2015, director Chai Jing developed a documentary depicting the bad effects on health of air pollution in China. However, soon after the release of the film, it was banned. One important finding in the film was the misperception the Chinese people had about the kinds of pollution and the health impacts. Therefore, this study aims to investigate the extent to which Chinese people understand the causes of air pollution and their related health effects. Accordingly, a survey was produced and delivered via Chinese social medium. The survey had three objectives: study the perception of 1) Air quality and the source of air pollution, 2) Health effects if air pollution, and 3) Air pollution and Environmental policies. The results show that 44% Chinese people feel air quality is worse now than a year before, and 72% people feel air pollution has affected their health. One main finding in this study was that younger people took the survey more than older people, as perhaps because they may have started to have a family or become a family; this is significant because air pollution is harmful for children. The other main finding was that 52% people did not know a China Air Pollution and Prevention Law exists.
299

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

Cheung, Ho-kwong., 張可光. January 1996 (has links)
published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
300

A study of suspended airborne particulates monitoring in Hong Kong

Tong, Wai-fong., 唐偉方. January 1997 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management

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