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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.
41

Development and application of a new passive sampling device : the lipid-free tube (LFT) sampler /

Quarles, Lucas W. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2010. / Printout. Includes bibliographical references. Also available on the World Wide Web.
42

The development of an immobilised-enzyme bioprobe for the detection of phenolic pollutants in water

Russell, Ingrid Margaret January 1999 (has links)
The possibility of developing an immobilised-enzyme bioprobe, based on mushroom polyphenol oxidase, for the purely biological detection and quantification of phenolic pollutants in water was investigated. Polyphenol oxidase catalyses the bioconversion of many phenolic compounds into quinone-related coloured products. Thus, in an immobilised form, the enzyme serves as a visible indicator of the presence and concentration of phenolic pollutants in water. The objective of this research was to develop a portable, disposable bioprobe incorporating polyphenol oxidase for this purpose. The intensity of the colour changes produced by the enzyme on reaction with p-cresol, p-chlorophenol and phenol was found to increase proportionally with increasing concentrations of these substrates in solution. Immobilisation of the enzyme on various supports did not appear to significantly affect the catalytic activity of the enzyme. The enzyme was immobilised by adsorption and cross-linking on polyethersulphone, nitrocellulose and nylon membranes with the production of various colour ranges on reaction with the phenolic substrates. The most successful immobilisation of the enzyme, in terms of quantity and distribution of enzyme immobilised and colour production, was obtained with the enzyme immobilised by adsorption on nylon membranes in the presence of 3-methyl-2-benzothiazolinone hydrazone (MBTH). The enzyme, immobilised using this method, produced ranges of maroon colours in phenolic solutions and orange colours in cresylic solutions. The colour intensities produced were found to increase proportionally with increasing substrate concentration after 5 minutes exposure to the substrates. The bioprobe had a broad substrate specificity and was sensitive to substrate concentrations down to 0.05 mg/L. The enzyme activity of the bioprobe was not significantly affected in a pH range from 4 to 10 and in a temperature range from 5-25⁰C. The bioprobe activity was not affected by various concentrations of salt and metal ions and the bioprobe was able to detect and semi-quantify phenolic substrates in industrial effluent samples. These features of the bioprobe indicate that the commercialisation of such a bioprobe is feasible and this technology has been patented (Patent No. SA 97/0227). / KMBT_363 / Adobe Acrobat 9.54 Paper Capture Plug-in
43

Estimativa da emissão de poluentes pelo setor de transporte e análise das ocorrências de doenças respiratórias na área de proteção ambiental do Sistema Cantareira / Estimation of pollutant emissions by sector and transport analysis of respiratory diseases in the area of environmental protection System Cantareira

Jesus, Cerise Rocha de 07 July 2011 (has links)
Orientador: Sônia Regina da Cal Seixas / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-18T23:26:18Z (GMT). No. of bitstreams: 1 Jesus_CeriseRochade_M.pdf: 2644103 bytes, checksum: 05f4712a8d58083a2d560698a273106d (MD5) Previous issue date: 2011 / Resumo: A matriz energética mundial é composta, principalmente, pelos combustíveis fósseis que, quando queimados, liberam poluentes atmosféricos afetando o meio ambiente e a saúde humana. Nesse sentido, o monitoramento de morbidades relacionadas à poluição do ar torna-se importante, porque reforça a necessidade de mudança na matriz energética nacional e internacional. Essa dissertação traz uma discussão sobre a poluição do ar decorrente dos transportes e sua influência na saúde humana, tendo como área de estudo das Rodovias Dom Pedro I (SP-065), construída no final da década de 60, e Fernão Dias (BR-381), duplicada a partir da década de 90. Sendo assim, o objetivo geral desse trabalho foi realizar estimativas de emissões de poluentes, gerados pelo setor de transporte nessas Rodovias, e verificar possíveis impactos dessas emissões na saúde da população residente na APA do Sistema Cantareira, no período de 1998 a 2007. Para realização desse estudo, utilizou-se o método Bottom-up que permite a identificação e quantificação das emissões dos poluentes separadamente, facilitando o estudo de políticas e projetos para a redução dessas emissões. Foi realizada, também, a observação e análise dos dados de internação por doenças do aparelho respiratório dos sete municípios da APA Cantareira, coletados no Banco de Dados do Sistema Único de Saúde- DATASUS. Buscou-se desenvolver este tipo de estudo devido ao fluxo intenso de carros e caminhões nas rodovias e também porque a maior parte das internações nos municípios da APA está acima da média do Estado de São Paulo. Essa dissertação de Mestrado em Planejamento de Sistemas Energéticos (PSE-FEM), Universidade Estadual de Campinas, contou com apoio financeiro da Fundação de Amparo a Pesquisa do Estado de São Paulo - FAPESP, através de bolsa de estudo (processo n.2009/04871-0) / Abstract: The global energy matrix is mainly composed by fossil fuels which when burned release air pollutants that affect the environment and human health. In this sense, monitoring health problems related to air pollution is important because it reinforces the need for change in national and international energy policies. This thesis presents a discussion on air pollution caused by transport and its influence on human health, with the study area of the Highways Dom Pedro I (SP-065) built in the late 60th and the duplication of the Highway Fernão Dias (BR -381) from the 90's. Thus, the general objective of this study was to estimate emissions of pollutants generated by the transportation sector on those Highways and verify the possible impacts of these emissions on the health of people living in APA Cantareira from 1998 to 2007. To conduct this study, we used the method Bottom-up that allows the identification and quantification of greenhouse gas emissions separately, facilitating the study of policies and projects designed to reduce those emissions. Was also carried out the observation and data analysis of hospital admission for respiratory diseases of the seven counties of the APA Cantareira collected in DATASUS. This study has been developed due to the heavy flow of cars and trucks on the highways and also because the majority of hospitalizations in the municipalities of the APA is above the average state of Sao Paulo. This Master's thesis in Energy Systems Planning (PSEFEM), University of Campinas had the financial support from the FAPESP, through a scholarship (process n.2009/04871- 0) / Mestrado / Planejamento de Sistemas Energeticos / Mestre em Planejamento de Sistemas Energéticos
44

Phosphorylated nanoporous β-cyclodextrin polymers: synthesis, characterization and their application in water purification

Simelane, Siphamandla 07 June 2012 (has links)
M.Sc. / This study was carried out to investigate the removal of organic and inorganic pollutants from water using phosphorylated and nonphosphorylated cyclodextrin polymers. The β-cyclodextrin was functionalized using various phosphorylating agents and the derivatives obtained were characterised with Fourier Transform-Infrared (FT-IR), Nuclear Magnetic Resonance (NMR) spectroscopy and mass spectrometry. These derivatives were polymerized using hexamethylene diisocyanate (HMDI) as a cross-linking agent. The polymers were obtained in good yields ranging from 72 % to 93 %. They were characterised using Fourier Transform-Infrared (FT-IR), Scanning Electron Microscopy/Energy Dispersive X-ray spectroscopy (SEM)/EDXS), Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA) to confirm the presence of phosphorus groups after polymerization. The removal of cadmium (II), chromium (III), trichlorophenol (TCP) and pentachlorophenol (PCP) was investigated in batch-mode experiments under varying conditions of pH, initial concentration and contact time. The concentration of heavy metal ions in water was determined using inductively-coupled plasma-optical emission spectroscopy (ICP-OES) and that of organic pollutants was determined using ultraviolet-visible (UV-Vis) spectroscopy. The polymers were found to adsorb up to chromium (III) better than cadmium (II) at pH 6.5. The maximum percentage removal of chromium (III) ranged between 83.9 % and 95 % whilst that of cadmium (II) ranged from 24.5 % to 39 %. There was no significant difference in the adsorption capacity of phosphorylated and phosphorus-free polymers in the removal of metals. However, phosphorylation improved the efficiency of the polymers in the removal of chlorophenols. The maximum percentage removal of TCP ranged from 17 % to 80.1 % whilst that of PCP ranged from 23 % to 77.2 %. The results obtained in this study demonstrate that the polymers are promising materials for the removal of Cr (III), TCP and PCP from water.
45

Biological treatment of hazardous air pollutants from corn-to-biofuel dry mill production facilities

Chen, Li-Jung 02 June 2010 (has links)
Development of renewable energy sources such as ethanol has become a priority to meet growing energy demands. In the United States, the majority of ethanol is produced at dry mill facilities that convert corn to ethanol; these facilities can be a major emission source for volatile organic compounds (VOCs). Biofiltration is a promising VOC control technology but its effectiveness for the VOC mixtures emitted from ethanol production facilities has yet to be determined. The main goal of this research was to evaluate the feasibility of using biofiltration to treat ethanol plant air pollutants. To accomplish this, microbial degradation of four representative pollutants (formaldehyde, acetaldehyde, ethanol and acetic acid) was examined first in simplified batch reactors and then in a laboratory-scale biofilter system. The batch data indicate that, at a neutral pH, an enriched microbial consortium was capable of completely degrading formaldehyde, acetaldehyde and ethanol, and the Monod model was successfully utilized to describe single substrate degradation kinetics for these pollutants. However, the consortium only partially degraded acetic acid. In binary substrate experiments, acetaldehyde degradation was not significantly affected by either ethanol or formaldehyde. However, acetaldehyde inhibition of ethanol degradation was observed and inhibition kinetics were necessary to describe the observed ethanol removals. Formaldehyde degradation was inhibited in the presence of acetaldehyde and/or ethanol; however, further research will be required to identify the inhibtion. The biofilter study was performed to investigate the effects of pollutant loading, substrate mixtures and low pH on system performance. The results indicate that it is feasible to achieve greater than 97% overall removal efficiency at a short contact time of 5 seconds under neutral pH conditions. The level of substrate inhibition observed in the batch experiments was not evident in the biofilter experiments. However, low pH conditions gradually decreased the biofilter performance with a more significant impact on acetaldehyde, a result that was supported by batch data. Finally, a numerical model that integrated degradation kinetics was able to describe the biofilter performance under the test conditions. This research demonstrates that biofiltration has the potential to be a viable VOC treatment technology at corn-derived ethanol production facilities. / text
46

The selective catalytic reduction of NO←x by CH←3OH under oxidising conditions over Al←2O←3 based catalysts

Halpin, Eibhlin January 1998 (has links)
No description available.
47

The impact of terraced agriculture upon water quality in the Middle Hills, Nepal

Collins, Robert Peter January 2000 (has links)
No description available.
48

Microbial production of an aromatic cis-1,2-dihydrodiol and its application in chemical synthesis

Sproule, Kenneth January 1992 (has links)
No description available.
49

Investigation of the treatment of mixed tannery wastewater

Song, Zhi January 2000 (has links)
No description available.
50

Indoor exposure to nitrogen dioxide in London

Colucci, Rosa January 1997 (has links)
No description available.

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