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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.
1

The analyses of polycyclic aromatic hydrocarbons in soils

Kaisaki, Frederick Mikio. January 1981 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1981. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 71-82).
2

Diversity of marine polycyclic aromatic hydrocarbon degrading bacteria and their dioxygenases /

Hedlund, Brian P. January 2000 (has links)
Thesis (Ph. D.)--University of Washington, 2000. / Vita. Includes bibliographical references (leaves 119-136).
3

Carcinogenic polycyclic aromatic hydrocarbons : theoretical, molecular, in vitro and cellular characterization of biotransformation and DNA damage /

Dreij, Kristian, January 2005 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2005. / Härtill 5 uppsatser.
4

Modulation of aryl hydrocarbon receptor (AhR) activity by flavonoids.

January 2011 (has links)
Poon, Ching Ho. / "October 2010." / Thesis (M.Phil.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 95-102). / Abstracts in English and Chinese. / ACKNOWLEDGEMENTS --- p.3 / TABLE OF CONTENTS --- p.4 / ABSTRACT --- p.6 / 摘要 --- p.8 / ABBREVIATIONS --- p.10 / LIST OF FIGURES --- p.11 / Chapter CHAPTER 1 --- GENERAL INTRODUCTION --- p.14 / Chapter CHAPTER 2 --- MATERIALS AND METHODS --- p.26 / Chemicals and materials --- p.26 / Mammalian cell culture --- p.27 / Reporter gene assay --- p.28 / Semi-quantitative real-time PCR --- p.30 / RNA degradation assay --- p.31 / Western Blotting --- p.32 / Electrophoretic mobility shift assay (EMSA) --- p.34 / EROD assay in intact cells --- p.35 / Statistical Analysis --- p.35 / Chapter CHAPTER 3 --- Two citrus bioflavonoids suppress DMBA-induced CYP1 gene expression and activity via antagonizing AhR transactivation activity --- p.36 / Chapter CHAPTER 4 --- Modulation of AhR-mediated CYP1 enzymes transcription by licorice flavonoids isoliquiritigenin --- p.60 / Chapter CHAPTER 5 --- Protein kinase signaling pathways are not involved in the modulation of AhR transactivation activity by flavonoids --- p.81 / Chapter CHAPTER 6 --- SUMMARY --- p.94 / BIBLIOGRAPHY --- p.97
5

The distribution and PAH-degradative potential of Cycloclasticus spp. in the marine environment /

Geiselbrecht, Allison D. January 1998 (has links)
Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographical references (leaves [106]-120).
6

Characterization of toxicological effects of a novel in vivo benzo[a]pyrene metabolite in colonic cells /

Nordling, Mirjam, January 2004 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 4 uppsatser.
7

Polycyclic heteroaromatic hydrocarbons containing a benzoisoindole core

Richter, Marcus, Schellhammer, Karl Sebastian, Machata, Peter, Cuniberti, Gianaurelio, Popov, Alexey, Ortmann, Frank, Berger, Reinhard, Müllen, Klaus, Feng, Xinliang 31 January 2020 (has links)
By the combination of 9a-azaphenalene and a perpendicularly oriented acene, we have synthesized three derivatives of a series of novel, fully-conjugated nitrogen-containing polycyclic aromatic hydrocarbons (PAHs), namely [7,8]naphtho[2′,3′:1,2]indolizino[6,5,4,3-def]phenanthridine, with an acetylene triisopropylsilyl (TIPS), phenyl or benzothiophenyl substituent. Their optoelectronic properties were studied via UV-Vis-NIR absorption, fluorescence spectroscopy and cyclic voltammetry. In addition, in situ spectroelectrochemistry was performed to investigate the optical and magnetic properties of the mono-radical cation and anion by quasi-reversible oxidation and reduction of 11-(tert-butyl)-5,17-bis((triisopropylsilyl)ethynyl)[7,8]naphtho[2′,3′:1,2]indolizino[6,5,4,3-def]phenanthridine (1a). Theoretical modelling confirmed the predominately closed-shell electronic ground state with a weak diradical character depending on the geometry.
8

Determinação de HPA em ambiente ocupacional de indústria de cimento que co-processa resíduos / Determination of PAH in occupational environment of a cement industry co-processing residues

Silva, Renata Pinho da 18 May 2009 (has links)
O co-processamento de resíduos em fornos de cimenteiras é uma alternativa de destinação de resíduos que consiste em substituir combustíveis ou matérias primas usados na fabricação do clínquer por diversos resíduos que apresentem poder calorífico e propriedades similares. Os resíduos são co-processados a temperaturas altas, porém podem ocorrer emissões de diversos poluentes devido a variedade de resíduos que podem ser co-processados. Entre esses poluentes estão os Hidrocarbonetos Policíclicos Aromáticos (HPA), que podem ser emitidos nas chaminés dos fornos das cimenteiras, ou também podem estar presentes no ambiente interno das mesmas. Considerando que os HPA são compostos orgânicos que apresentam potencial carcinogênico e/ou mutagênico, e assim oferecem risco à saúde humana, esse estudo tem o objetivo apresentar uma avaliação preliminar da presença e dos níveis de concentração de HPA em uma indústria de cimento que co-processa resíduos. As análises de HPA no ambiente ocupacional foram realizadas seguindo a metodologia proposta do NIOSH (National Institute for Occupational Safety and Health). Para isso utilizou-se como ferramenta analítica a técnica de cromatografia a líquido de alto desempenho (CLAE) com detecção por fluorescência, acompanhada da otimização e avaliação dos principais parâmetros analíticos do método, possibilitando assim a determinação dos 17 HPA prioritários pela NIOSH com confiabilidade analítica. Os resultados indicaram a presença de vários HPA no ambiente de trabalho estudado, porém numa concentração baixa (faixa de ng.m-3) e dentro da faixa de concentração encontrada em trabalhos em ambientes convencionais. Este estudo foi desenvolvido com a colaboração da FUNDACENTRO/MTE. / The co-processing of residues in furnaces of cement industries is an alternative to dispose residues by substituting conventional combustibles and raw materials used for production of clinker by diverse organic residues of similar properties and calorific power. Co-processing is made at high temperatures, but emission of diverse pollutants may occur as a consequence of the large diversity of residues that are processed. Among these pollutants, Polycyclic Hydrocarbons (PAH) may be either emitted in the chimneys of the furnaces, or be present in the interior ambient of these industries. PAH pose risk to human health because they are organic compounds having potential carcinogenic and mutagenic activities. The present study aims to show the results of a preliminary evaluation of the presence and concentration levels of PAH in a cement industry co-processing residues. PAH analyses in the occupational environment were made according the methodology recommended by NIOSH (National Institute of Occupational Safety and Health). High performance chromatography (HPLC) with fluorescence detection was the analytical technique used for analyses. Optimization and evaluation of the major analytical parameters allowed the determination of the 17 PAH prioritized by NIOSH to be made with analytical confidence. Results showed the presence of several PAH in the studied environment, but at low concentrations (in the range of ng.m-3). These concentrations are of similar magnitude to the ones found in conventional environments. The present study was made in collaboration with FUNDACENTRO/MTE.
9

Determinação de HPA em ambiente ocupacional de indústria de cimento que co-processa resíduos / Determination of PAH in occupational environment of a cement industry co-processing residues

Renata Pinho da Silva 18 May 2009 (has links)
O co-processamento de resíduos em fornos de cimenteiras é uma alternativa de destinação de resíduos que consiste em substituir combustíveis ou matérias primas usados na fabricação do clínquer por diversos resíduos que apresentem poder calorífico e propriedades similares. Os resíduos são co-processados a temperaturas altas, porém podem ocorrer emissões de diversos poluentes devido a variedade de resíduos que podem ser co-processados. Entre esses poluentes estão os Hidrocarbonetos Policíclicos Aromáticos (HPA), que podem ser emitidos nas chaminés dos fornos das cimenteiras, ou também podem estar presentes no ambiente interno das mesmas. Considerando que os HPA são compostos orgânicos que apresentam potencial carcinogênico e/ou mutagênico, e assim oferecem risco à saúde humana, esse estudo tem o objetivo apresentar uma avaliação preliminar da presença e dos níveis de concentração de HPA em uma indústria de cimento que co-processa resíduos. As análises de HPA no ambiente ocupacional foram realizadas seguindo a metodologia proposta do NIOSH (National Institute for Occupational Safety and Health). Para isso utilizou-se como ferramenta analítica a técnica de cromatografia a líquido de alto desempenho (CLAE) com detecção por fluorescência, acompanhada da otimização e avaliação dos principais parâmetros analíticos do método, possibilitando assim a determinação dos 17 HPA prioritários pela NIOSH com confiabilidade analítica. Os resultados indicaram a presença de vários HPA no ambiente de trabalho estudado, porém numa concentração baixa (faixa de ng.m-3) e dentro da faixa de concentração encontrada em trabalhos em ambientes convencionais. Este estudo foi desenvolvido com a colaboração da FUNDACENTRO/MTE. / The co-processing of residues in furnaces of cement industries is an alternative to dispose residues by substituting conventional combustibles and raw materials used for production of clinker by diverse organic residues of similar properties and calorific power. Co-processing is made at high temperatures, but emission of diverse pollutants may occur as a consequence of the large diversity of residues that are processed. Among these pollutants, Polycyclic Hydrocarbons (PAH) may be either emitted in the chimneys of the furnaces, or be present in the interior ambient of these industries. PAH pose risk to human health because they are organic compounds having potential carcinogenic and mutagenic activities. The present study aims to show the results of a preliminary evaluation of the presence and concentration levels of PAH in a cement industry co-processing residues. PAH analyses in the occupational environment were made according the methodology recommended by NIOSH (National Institute of Occupational Safety and Health). High performance chromatography (HPLC) with fluorescence detection was the analytical technique used for analyses. Optimization and evaluation of the major analytical parameters allowed the determination of the 17 PAH prioritized by NIOSH to be made with analytical confidence. Results showed the presence of several PAH in the studied environment, but at low concentrations (in the range of ng.m-3). These concentrations are of similar magnitude to the ones found in conventional environments. The present study was made in collaboration with FUNDACENTRO/MTE.
10

π-Extended and Curved Antiaromatic Polycyclic Hydrocarbons

Liu, Junzhi, Ma, Ji, Zhang, Ke, Ravat, Prince, Machata, Peter, Avdoshenko, Stanislav, Hennersdorf, Felix, Komber, Hartmut, Pisula, Wojciech, Weigand, Jan J., Popov, Alexey A., Berger, Reinhard, Müllen, Klaus, Feng, Xinliang 06 January 2020 (has links)
Synthesis of antiaromatic polycyclic hydrocarbons (PHs) is challenging because the high energy of their highest occupied molecular orbital and low energy of their lowest unoccupied molecular orbital cause them to be reactive and unstable. In this work, two large antiaromatic acene analogues, namely, cyclopenta[pqr]indeno[2,1,7-ijk]tetraphene (CIT, 1a) and cyclopenta[pqr]indeno[7,1,2-cde]picene (CIP, 1b), as well as a curved antiaromatic molecule with 48 πelectrons, dibenzo[a,c]diindeno[7,1,2-fgh:7′,1′,2′-mno]-phenanthro[9,10-k]tetraphene (DPT, 1c), are synthesized on the basis of the corona of indeno[1,2-b]fluorene. These three antiaromatic PHs possess a narrow energy gap down to 1.55 eV and exhibit high kinetic stability under ambient conditions. Moreover, these compounds display reversible electron transfer processes in both the cathodic and anodic regimes. Their cation and anion radicals are characterized by in situ vis−NIR absorption and electron paramagnetic resonance spectroelectrochemistry. The X-ray crystallographic analysis confirms that while CIP and CIT manifest planar structures, DPT shows a curved πconjugated carbon skeleton. The synthetic strategy starting from ortho-substituted benzene units to construct five-membered rings in this work provides a unique entry to novel pentagon-embedding or curved antiaromatic polycyclic hydrocarbons. In addition, besides the detailed chemical and physical investigations, microscale single-crystal fiber field-effect transistors were also fabricated.

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