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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.
171

STEAM EXTRACTION OF POLYCYCLIC AROMATIC HYDROCARBONS AND LEAD FROM CONTAMINATED SEDIMENT USING SURFACTANT, SALT AND AKALINE CONDITIONS

WEINKAM, GRANT 03 July 2007 (has links)
No description available.
172

Firefighters’ Exposure to Fine Particles and Polycyclic Aromatic Hydrocarbons

Hoffman, Joseph D. 19 October 2010 (has links)
No description available.
173

Effects of Cyclodextrin on Extraction and Fungal Remediation of Polycyclic Aromatic Hydrocarbon-contaminated Mahoning River Sediment

Pabba, Sowmya 02 September 2008 (has links)
No description available.
174

Time-Dependent Density-Functional Description of the <sup>1</sup>L<sub>a</sub> State in Polycyclic Aromatic Hydrocarbons

Richard, Ryan M. 20 July 2011 (has links)
No description available.
175

Photoluminescence by Interstellar Dust

Vijh, Uma Parvathy 05 October 2005 (has links)
No description available.
176

The synthesis of some new aromatic polycyclic hydrocarbons

Ojakaar, Leo January 1964 (has links)
In 1933, benzo[a]pyrene, a hydrocarbon, which was and still is of very great importance for cancer research, was isolated from coal tar and also was synthesized. In recent years more than 450 synthetic compounds have been found to be carcinogenic, and more than 200 are polycyclic aromatic hydrocarbons, their derivatives and analogues. Recently a new polynuclear hydrocarbon, a seven ring compound naphtho[2,1-a]perylene was synthesized in This Laboratory Physiological tests have revealed this compound to be a potent carcinogen. This experience has prompted a new initiative to prepare a number of related compounds of this type in order to bring further insight to the relation between chemical structure and the mechanism of physiological activity. During the synthesis of the four new seven fused aromatic ring systems and a new eight fused aromatic ring system, several modifications and improvement of existing synthetic procedures were made. A recently published modification of the Rosenmund-von Braun method of nitrile synthesis was successfully applied to the preparation of 2-(2-naphthylmethyl)benzonitrile. It was found that 2-(2-naphthylmethyl)phenyl-1-naphthyl ketone and 2-(2-naphthylmethyl)phenyl-2-naphthyl ketone could be prepared by the reaction of a Grignard reagent with a nitrile as well as by the inverse addition of a Grignard reagent to the appropriate acid chlorides. The alumina cyclodehydrogenation procedure was confirmed to be the, only method of synthesis that yields 12-(1-naphthyl)-benz[a]anthracene from its precursor ketone. The yield of 12-(2-naphthyl)benz[a]anthracene was increased from 61% to 83% when anhydrous hydrogen fluoride was used in place of 48% hydrogen bromide and glacial acidic acid as the cyclodehydration media of the precursor ketone. A new cyclodehydrogenation procedure was developed. This procedure, which employs a mixture of aluminum chloride-stannic chloride and alumina, was used to prepare a new hydrocarbon, naphtho[l,2-a]-perylene. An aluminum chloride-sodium chloride melt permeated with carbon dioxide was successfully employed in the preparation of naphtho[2,2-1]benzo- (a]pyrene, naphtho(l,2-l]benzo[a]pyrene, and naphtho- (2,3-1]benzo[a]pyrene. It was shown that high temperature gas chromatography with ionization detectors can be used with success to analyze all of the above discussed ketones, benz[a]anthracenes as well as the new perylene and pyrenes. Additional support of the validity of the. structures of naphtho[1,2-a]perylene and naphtho- [2,1-1]benzo[a]pyrene was provided when the cyclodehydrogenation of these hydrocarbons yielded one and the same product, naphtho[l,7,8-efg]anthanthrene. It was observed that the correlation between color and structure of the newly prepared hydrocarbons follows the principles of annelation. When the ultraviolet and visible spectra peak frequencies were compared it was found that the values and positions of the peaks follow the principles of the annelation method. The examination of the infrared absorption spectra revealed that naphtho[l,2-a]perylene, naphtho[2,1l-1]benzo[a]pyrene, naphtho[1,2-1]benzo[a]-pyrene, and naphtho[2,3-1]benzo[a]pyrene exhibited Peaks at all four, "solo," "duo," "trio," and "quartet", carbon-hydrogen vibration regions, but as expected naphtho[1,7,8-efg]anthanthrene had the "quartet" carbon-hydrogen peak missing between 770 and 755 cm. which further substantiated the validity of the naphtho[1,7,8-efg]anthanthrene structure. The TNF molecular adducts of the five newly prepared compounds, naphtho[1,2-a]perylene, naphtho- [2,1-1]benzo[a]pyrene, naphtho1l,2-1]benzo[a]pyrene, naphtho[2,3-1]benzo[a]pyrene, and naphtho[1,7,8-efg]-anthanthrene were prepared and their melting points recorded. In order to ascertain the structures of the naphtho[1,2-a]perylene and the naphtho[1,2-l]benzo[a]-pyrene obtained from the cyclodehydrogenation of 12-(1-naphthyl)benz[a]anthracene and 12-(2-naphthyl)-benz[a]anthracene, respectively, other routes of synthesis were undertaken. The hydrocarbon, 11-(1-naphthyl)benz[a]anthracene, was prepared by the reaction of 1-naphthylmagnesium bromide with 11-keto-5,6,8,9,10,11-hexahydrobenz[a]- anthracene which on distillation under reduced pressure gave 11-(1-naphthyl)-5,6,8,9-tetrahydrobenz[a]anthracene and on aromatization yielded 11-(1-naphthyl)benz[a]-anthracene. When 1-naphthyl magnesium bromide was allowed to react with the 11-keto-8,9,10,11-tetrahydrobenz[a]anthracene, 11-(1-naphthyl)-8,9~dihydrobenz[a]anthracene was obtained when distilled under reduced pressure. This, likewise, gave 11-(1-naphthyl)- benz[a]anthracene on aromatization. Naphtho[1,2-a]perylene was synthesized unequivocally from 11-(1-naphthyl)benz[a]anthracene via a cyclodehydrogenation reaction. The hydrocarbon, 1-(1-naphthyl)-1,2,3,4-tetrahydrobenz[a]anthracene, was prepared by the reaction of 1-naphthylmagnesium bromide with 1-keto-1,2,3,4- tetrahydrobenz[a]anthracene. On distillation under reduced pressure 1-(1-naphthyl)-1,2,3,4-tetrahydrobenz[a]anthracene was obtained. Under the conditions of an aromatization procedure, naphtho[1,2-1]benzo[a]-pyrene was obtained. The hydrocarbons 11-(1l-naphthyl)-5,6,8,9-tetrahydrobenz[a]anthracene, 11-(1-naphthyl)-8,9-dihydrobenz[a]anthracene, 11-(1-naphthyl)benz[a]-anthracene, 1-(1-naphthyl)-1,2,3,4-tetrahydrobenz[a]anthracene are additional new compounds. / Ph. D.
177

The synthesis and reactions of 2-(1-Naphthylmethyl)-2'- Carboxybenzophenone

Greenwood, Edward James 09 November 2012 (has links)
The structures of the six new compounds and the TNF molecular complex were substantiated by satisfactory elemental analyser. The infrared and ultraviolet absorption spectra of the six new compounds were recorded. / Master of Science
178

The biosynthesis of ravidomycin

Keyes, Robert F. 25 August 2008 (has links)
Ravidomycin is a yellow antitumor antibiotic produced by Streptomyces ravidus. Ravidomycin shows strong antitumor activity against P388 lymphocytic leukemia, the colon 38 tumor, and the CD8Fl mammary tumor. It is also very active against Gram positive bacteria. Biosynthetic studies have shown that the aglycone unit comes from the folding of a polyketide chain with the vinyl unit arising from propionic acid. Since this vinyl functionality is believed to playa role in the antitumor activity of the antibiotic, it is of interest to elucidate the stereochemical selectivity in its formation from propionic acid. The synthesis of (R) and (S)-L2-²H₁ j propionate, incorporation of the labelled material, and chemical analysis of the resulting antibiotic was be used to determine the stereochemistry of formation of the vinyl side chain. It was found that propionate was incorporated with ravidomycin with stereospecific loss of the 2-(pro-R)-proton. / Master of Science
179

The polycyclic aromatic hydrocarbon content and mutagenicity of the residue from cane burning and vehicle emissions.

Godefroy, Susan Jessica. January 1992 (has links)
Polycyclic (or polynuclear) aromatic hydrocarbons (PAHs) are environmental pollutants produced during the incomplete combustion of organic matter. Since many of these compounds have been shown to be mutagenic and/or carcinogenic, an investigation was initiated into determining the PAH content and mutagenicity of the ash that remains after sugar cane crop burning, and the soot deposited on toll booths by vehicle exhaust emissions. Due to the large amount of sugar cane farming in the Natal coastal region and that the favoured method of disposing unwanted leafy trash is crop burning, concern was expressed as to the nature of the residue that is formed. PAHs have been identified in the residues from combusted wood and straw and, due to their intrinsic similarity to sugar cane, it was considered that the burning of sugar cane could generate PAHs. It is well documented that vehicle exhaust emissions exhibit mutagenic properties and PAHs have been identified as the major contributors of this observed mutagenicity. Since a toll plaza is an area of high traffic density, it was considered to be an ideal location for an investigation into the build-up of particles emitted by the passing vehicles, and to study to what extent the operators are exposed to harmful compounds. In addition, this sample acted as a control, since the detection of PAHs and mutagenic activity in the soot would be an indication that the correct experimental techniques were being employed. Samples were collected on site. The sugar cane ash was collected off a field immediately after burning had taken place, and the soot was collected either by scraping the toll booth walls and surrounding areas or by wiping the surfaces with cotton wool swabs. The organic portion of the samples was separated from the inorganic and carbonaceous substances by extraction into a suitable solvent; the use of both acetone and dichloromethane was investigated. The extracts were divided into two portions - one was used for the analysis of PAHs and the other for determining mutagenic activity. Analysis for PAHs involved subjecting the extracts to a sample clean-up routine and the use of a number of analytical techniques to characterise the components. The mutagenic properties of the samples were investigated by means of two bacterial mutagenicity tests: the Salmonella typhimurium assay (the Ames test) and a new commercially available test kit, the SOS Chromotest. A number of PARs were identified in the extracts by means of reverse phase high performance liquid chromatography (HPLC) with both ultraviolet and fluorescence detection, the latter being the more sensitive method. Mutagenic activity was detected for both samples in the Ames test and for the toll booth soot in the SOS Chromotest, and this observed mutagenicity was attributed to the presence of the PAHs. / Thesis (M.Sc.)-University of Natal, Durban, 1992.
180

Remediation of abandoned shipyard soil by organic amendment using compost of fungus Pleurotus pulmonarius.

January 2005 (has links)
by Chan Sze Sze. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 193-218). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abstracts --- p.ii / 摘要 --- p.v / Contents --- p.viii / List of figures --- p.xv / List of tables --- p.xix / Abbreviations --- p.xxii / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- The North Tsing Yi Abandoned Shipyard area --- p.1 / Chapter 1.2 --- Polycyclic aromatic hydrocarbons (PAHs) in the site --- p.3 / Chapter 1.2.1 --- Characteristics of PAHs --- p.3 / Chapter 1.2.2 --- Sources of PAHs --- p.8 / Chapter 1.2.3 --- Environmental fates of PAHs --- p.9 / Chapter 1.2.4 --- Biodegradation of PAHs --- p.10 / Chapter 1.2.5 --- Toxicity of PAHs --- p.13 / Chapter 1.2.6 --- PAHs contamination in Hong Kong --- p.14 / Chapter 1.2.7 --- Soil decontamination assessment in Hong Kong --- p.16 / Chapter 1.2.8 --- Environmental standards of PAHs --- p.18 / Chapter 1.2.9 --- Remediation technology of PAHs --- p.21 / Chapter 1.2.9.1 --- Bioremediation --- p.22 / Chapter 1.3 --- Heavy metals in the site --- p.28 / Chapter 1.3.1 --- "Characteristics of copper, lead and zinc" --- p.29 / Chapter 1.3.2 --- "Sources of copper, lead and zinc" --- p.32 / Chapter 1.3.3 --- "Environmental fates of copper, lead and zinc" --- p.34 / Chapter 1.3.4 --- "Toxicities of copper, lead and zinc" --- p.36 / Chapter 1.3.5 --- "Copper, lead and zinc contamination in Hong Kong" --- p.39 / Chapter 1.3.6 --- "Environmental standards of copper, lead and zinc" --- p.40 / Chapter 1.3.7 --- Remediation technology of heavy metal --- p.42 / Chapter 1.3.7.1 --- Chemical method --- p.42 / Chapter 1.3.7.2 --- Biological method --- p.43 / Chapter 1.3.7.3 --- Stabilization and Solidification --- p.45 / Chapter 1.4 --- Aim of study --- p.47 / Chapter 1.5 --- Objectives --- p.47 / Chapter 1.6 --- Research Strategy --- p.47 / Chapter 1.7 --- Significance of study --- p.48 / Chapter 2 --- Materials and Methods --- p.49 / Chapter 2.1 --- Soil Collection --- p.49 / Chapter 2.2 --- Characterization of soil --- p.49 / Chapter 2.2.1 --- Sample preparation --- p.49 / Chapter 2.2.2 --- "Soil pH, electrical conductivity & salinity" --- p.50 / Chapter 2.2.3 --- Total organic carbon contents --- p.51 / Chapter 2.2.4 --- Soil texture --- p.51 / Chapter 2.2.5 --- Moisture --- p.53 / Chapter 2.2.6 --- Total nitrogen and total phosphorus --- p.53 / Chapter 2.2.7 --- Available nitrogen --- p.53 / Chapter 2.2.8 --- Available phosphorus --- p.54 / Chapter 2.2.9 --- Soil bacterial and fungal population --- p.54 / Chapter 2.2.10 --- Extraction of PAHs and organic pollutants --- p.55 / Chapter 2.2.10.1 --- Extraction procedure --- p.55 / Chapter 2.2.10.2 --- GC-MS condition --- p.56 / Chapter 2.2.10.3 --- Preparation of mixed PAHs stock solution --- p.56 / Chapter 2.2.11 --- Oil and grease content --- p.57 / Chapter 2.2.12 --- Total Petroleum Hydrocarbons (TPH) --- p.57 / Chapter 2.2.13 --- Total heavy metal analysis --- p.58 / Chapter 2.2.14 --- Toxicity characteristic leaching procedure (TCLP) --- p.59 / Chapter 2.2.15 --- Extraction efficiency --- p.59 / Chapter 2.3 --- Production of mushroom compost --- p.60 / Chapter 2.4 --- Characterization of mushroom compost --- p.62 / Chapter 2.4.1 --- Enzyme assay --- p.62 / Chapter 2.4.1.1 --- Laccase assay --- p.62 / Chapter 2.4.1.2 --- Manganese peroxidase assay --- p.62 / Chapter 2.5 --- Addition of mushroom to soil on site --- p.63 / Chapter 2.5.1 --- Transportation of mushroom compost to Tsing Yi --- p.63 / Chapter 2.5.2 --- Mixing of mushroom compost and soil --- p.64 / Chapter 2.6 --- Soil Monitoring --- p.64 / Chapter 2.6.1 --- On site air and soil measurements --- p.64 / Chapter 2.6.1.1 --- Air temperature and moisture --- p.64 / Chapter 2.6.1.2 --- Light intensity --- p.64 / Chapter 2.6.1.3 --- UV intensity --- p.65 / Chapter 2.6.1.4 --- Rainfall --- p.65 / Chapter 2.6.1.5 --- Soil temperature --- p.65 / Chapter 2.6.2 --- Soil chemical characteristic --- p.65 / Chapter 2.6.3 --- Relative residue pollutant (%) --- p.65 / Chapter 2.7 --- Toxicity of treated soil --- p.66 / Chapter 2.7.1 --- Seed germination test --- p.66 / Chapter 2.7.2 --- Indigenous bacterial toxicity test --- p.67 / Chapter 2.7.3 --- Fungal toxicity test --- p.68 / Chapter 2.7.3.1 --- Preparation of ergosterol standard solution --- p.70 / Chapter 2.8 --- Soil Washing --- p.70 / Chapter 2.8.1 --- Optimization of soil washing --- p.70 / Chapter 2.8.1.1 --- Effect of hydrochloric acid concentration --- p.70 / Chapter 2.8.1.2 --- Effect of incubation time --- p.71 / Chapter 2.9 --- Phytoremediation --- p.71 / Chapter 2.10 --- Mycoextraction --- p.72 / Chapter 2.11 --- Integrated bioextraction --- p.72 / Chapter 2.12 --- Cementation --- p.73 / Chapter 2.13 --- Glass encapsulation --- p.73 / Chapter 2.14 --- Statistical analysis --- p.74 / Chapter 3 --- Results --- p.75 / Chapter 3.1 --- Characterization of soil --- p.75 / Chapter 3.2 --- Characterization of mushroom compost --- p.78 / Chapter 3.2.1 --- Enzyme activity --- p.78 / Chapter 3.2.2 --- Total nitrogen and total phosphorus contents --- p.78 / Chapter 3.3 --- Soil monitoring --- p.79 / Chapter 3.3.1 --- Initial pollutant content in biopile and fungal treatment soils --- p.79 / Chapter 3.3.2 --- On site air and soil physical characteristics --- p.81 / Chapter 3.3.2.1 --- Soil temperature and air temperature --- p.81 / Chapter 3.3.3 --- Soil chemical characteristic --- p.84 / Chapter 3.3.3.1 --- Effect of type of treatment on total petroleum hydrocarbon content --- p.85 / Chapter 3.3.3.2 --- Effect of type of treatment on oil and grease content --- p.87 / Chapter 3.3.3.3 --- Soil pH --- p.89 / Chapter 3.3.3.4 --- Moisture --- p.91 / Chapter 3.3.3.5 --- Electrical conductivity --- p.92 / Chapter 3.3.3.6 --- Salinity --- p.93 / Chapter 3.3.3.7 --- Microbial population --- p.95 / Chapter 3.3.3.8 --- Removal of organopollutant PAHs in biopile and fungal treatment --- p.98 / Chapter 3.3.3.9 --- Effect of type of treatment on residual PAHs at Day 4 --- p.104 / Chapter 3.3.3.10 --- Effect of type of treatment on residual PAHs at peak levels --- p.107 / Chapter 3.3.3.11 --- Effect of type of treatment on residual organopollutants at the end of treatments --- p.109 / Chapter 3.3.3.12 --- Effect of type of treatment on total nitrogen and phosphorus contents --- p.111 / Chapter 3.3.3.13 --- Effect of type of treatment on physical and chemical properties of soil --- p.113 / Chapter 3.4 --- Toxicity of treated soil --- p.116 / Chapter 3.4.1 --- Seed germination test --- p.116 / Chapter 3.4.2 --- Indigenous bacterial toxicity test --- p.120 / Chapter 3.4.3 --- Fungal toxicity test --- p.125 / Chapter 3.5 --- Soil washing --- p.129 / Chapter 3.5.1 --- Optimisation of soil washing --- p.129 / Chapter 3.5.1.1 --- The effect of hydrochloric acid concentration --- p.129 / Chapter 3.5.1.2 --- The effect of incubation time --- p.134 / Chapter 3.6 --- Mycoextraction --- p.139 / Chapter 3.7 --- Phytoextraction and integrated bioextraction --- p.146 / Chapter 3.8 --- Cementation --- p.153 / Chapter 3.9 --- Glass encapsulation --- p.158 / Chapter 4 --- Discussion --- p.160 / Chapter 4.1 --- Characterization of soil --- p.160 / Chapter 4.2 --- Characterization of mushroom compost --- p.162 / Chapter 4.2.1 --- Enzyme activity --- p.162 / Chapter 4.2.2 --- Total nitrogen and total phosphorus contents --- p.163 / Chapter 4.3 --- Soil monitoring --- p.163 / Chapter 4.3.1 --- Initial pollutant content in biopile and fungal treatment soil --- p.163 / Chapter 4.3.2 --- On site air and soil physical characteristics --- p.164 / Chapter 4.3.3 --- Soil chemical characteristic --- p.164 / Chapter 4.3.3.1 --- Soil pH --- p.164 / Chapter 4.3.3.2 --- Moisture --- p.165 / Chapter 4.3.3.3 --- Electrical conductivity --- p.165 / Chapter 4.3.3.4 --- Salinity --- p.166 / Chapter 4.3.3.5 --- Microbial population in biopile and fungal treatments --- p.166 / Chapter 4.3.3.6 --- Removal of organopollutant PAHs in biopile and fungal treatments --- p.168 / Chapter 4.3.3.7 --- Effect of type of treatment on residual PAHs at peak levels --- p.170 / Chapter 4.3.3.8 --- Effect of type of treatment on residual oil and grease and TPH contents --- p.171 / Chapter 4.3.3.9 --- Effect of type of treatment on total nitrogen and phosphorus contents --- p.172 / Chapter 4.3.3.10 --- Effect of type of treatment on physical and chemical properties of the soil --- p.173 / Chapter 4.4 --- Toxicity of treated soil --- p.174 / Chapter 4.5 --- Summary of Pleurotus pulmonarius mushroom compost on organopollutant remediation --- p.177 / Chapter 4.6 --- Soil washing --- p.178 / Chapter 4.7 --- Mycoextraction --- p.180 / Chapter 4.8 --- Phytoextraction and integrated bioextraction --- p.182 / Chapter 4.9 --- Cementation --- p.184 / Chapter 4.10 --- Glass encapsulation --- p.185 / Chapter 4.11 --- "Summary of physical, chemical and biological heavy metal removal treatments" --- p.186 / Chapter 4.12 --- Future studies --- p.187 / Chapter 5 --- Conclusion --- p.190 / Chapter 6 --- References --- p.193

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