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Nitrifyers in constructed wetlands treating landfill leachates /Sundberg, Carina, January 2008 (has links) (PDF)
Diss. (sammanfattning) Linköping : Linköpings universitet, 2008. / Härtill 4 uppsatser.
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Ecological studies of litter production and decomposition in a mixed forest in Hong Kong with special reference to ficus fistulosa reinv.ex B1. (moraceae)林群聲, Lam, Kwan-sing, Paul. January 1984 (has links)
published_or_final_version / Zoology / Master / Master of Philosophy
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Microbial degradation of methyl red and its reductive cleavage products.January 1993 (has links)
by Yuen Pui-yee, Joyce. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1993. / Includes bibliographical references (leaves 213-221). / Acknowledgments --- p.i / Abstract --- p.ii / List of Tables --- p.ix / List of Figures --- p.xi / Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Problems of Pollution From Textile Industries --- p.1 / Chapter 1.2 --- Current Treatment Methods of Wastewater from Textile Industries --- p.5 / Chapter 1.3 --- Adverse Effects of Dyes on the Environment --- p.11 / Chapter 1.4 --- Classification of Dyes --- p.16 / Chapter 1.5 --- Azo Dyes --- p.17 / Chapter 1.6 --- Metabolisms of Azo Dyes in Microbial and Animal Systems --- p.21 / Chapter 1.7 --- "Toxicity, Mutagenicity and Carcinogenicity of Azo Dyes" --- p.31 / Chapter 1.8 --- Removal of Azo Dyes --- p.35 / Chapter 1.8.1 --- Biological Methods --- p.35 / Chapter 1.8.2 --- Physico-chemical Methods --- p.49 / Chapter 1.9 --- Purposes of Study --- p.50 / Chapter 2. --- Objectives --- p.53 / Chapter 3. --- Materials and Methods --- p.54 / Chapter 3.1 --- "Isolation, Selection and Characterization of Methyl Red-degrading and N,N-Dimethyl-p-phenylene diamine-degrading Microbial Isolates" --- p.54 / Chapter 3.1.1 --- "Isolation of Methyl Red-degrading Microbial Isolates from Dye- containing Wastewater, Activated Sludge and Soil" --- p.54 / Chapter 3.1.2 --- Selection of Methyl Red-degrading Microbial Isolates --- p.56 / Chapter 3.1.3 --- "Enrichment of N,N-Dimethyl-p-phenylene diamine-degrading Bacteria from Dye-containing wastewater, Activated Sludge and Soil" --- p.59 / Chapter 3.1.4 --- "Isolation of N,N-Dimethyl-p-phenylene diamine-degrading Bacteria " --- p.60 / Chapter 3.1.5 --- Selection of N,N-Dimethyl-p-phenylene diamine-degrading Bacteria --- p.60 / Chapter 3.1.6 --- "Identification of the Selected Methyl Red-degrading and N,N- Dimethyl-p-phenylene diamine-degrading Bacteria " --- p.61 / Chapter 3.1.7 --- Correlationship of Dry Weight and Absorbance of Cells of Selected Methyl Red-degrading Bacterial Isolates --- p.63 / Chapter 3.2 --- "Characterization of Methyl Red, N,N-Dimethyl-p-phenylene diamine and o-Aminobenzoic acid " --- p.64 / Chapter 3.2.1 --- "Chemical Stability of Methyl Red, N,N-Dimethyl-p-phenylene diamine and o-Aminobenzoic acid " --- p.64 / Chapter 3.2.2 --- Change of UV-Vis Spectra of Methyl Red and N,N-Dimethyl-p- phenylene diamine at Different pH and Matrixes --- p.64 / Chapter 3.2.3 --- "UV-Vis Spectra and Standard Curves of Methyl Red, N,N- Dimethyl-p-phenylene diamine and o-Aminobenzoic acid " --- p.66 / Chapter 3.2.4 --- "HPLC separation of Methyl Red, N,N-Dimethyl-p-phenylene diamine and o-Aminobenzoic acid " --- p.67 / Chapter 3.3 --- Methyl Red Degradation by Selected Methyl Red-degrading Microbial Isolates --- p.68 / Chapter 3.3.1 --- "Monitoring of Percentage of Methyl Red Cleaved, Degradation Value of N,N-Dimethyl-p-phenylene diamine and o- Aminobenzoic acid, and Growth of Selected Methyl Red- degrading Bacteria by Spectrophotometric Analysis " --- p.68 / Chapter 3.3.2 --- Study of Degrading Products of Methyl Red by Selected Methyl Red-degrading Isolates --- p.71 / Chapter 3.4 --- Degradation of Other Azo Dyes by Selected Methyl Red-degrading Isolates --- p.73 / Chapter 4. --- Results --- p.74 / Chapter 4.1 --- "Isolation, Selection and Characterization of Methyl Red-degrading and N,N-dimethyl-p-phenylene diamine-degrading Microbial Isolates " --- p.74 / Chapter 4.1.1 --- "Isolation of Methyl Red-degrading Microbial Isolates from Dye- containing Wastewater, Activated Sludge and Soil " --- p.74 / Chapter 4.1.2 --- Selection of Methyl Red-degrading Microbial Isolates --- p.79 / Chapter 4.1.3 --- "Enrichment of N,N-dimethyl-p-phenylene diamine-degrading Bacteria from Dye-containing Wastewater, Activated Sludge and Soil " --- p.85 / Chapter 4.1.4 --- "Isolation of N,N-Dimethyl-p-phenylene diamine-degrading Bacteria " --- p.85 / Chapter 4.1.5 --- "Selection of N,N-Dimethyl-p-phenylene diamine-degrading Bacteria " --- p.90 / Chapter 4.1.6 --- "Identification of the Selected Methyl Red-degrading and N,N- Dimethyl-p-phenylene diamine-degrading Bacteria " --- p.90 / Chapter 4.1.7 --- Correlationship of Dry Weight and Absorbance of Cells of Selected Methyl Red-degrading Bacterial Isolates --- p.94 / Chapter 4.2 --- "Characterization of Methyl Red, N,N-Dimethyl-p-phenylene diamine and o-Aminobenzoic acid " --- p.94 / Chapter 4.2.1 --- "Chemical Stability of Methyl Red, N,N-Dimethyl-p-phenylene diamine and o-Aminobenzoic acid " --- p.94 / Chapter 4.2.2 --- "Change of UV-Vis Spectra of Methyl Red and N,N-Dimethyl-p- phenylene diamine at Different pH and Matrixes " --- p.108 / Chapter 4.2.3 --- "UV-Vis Spectra and Standard Curves of Methyl Red, N,N- Dimethyl-p-phenylene diamine and o-Aminobenzoic acid " --- p.123 / Chapter 4.2.4 --- "HPLC Separation of Methyl Red, N,N-Dimethyl-p-phenylene diamine and o-Aminobenzoic acid " --- p.129 / Chapter 4.3 --- Methyl Red Degradation by Selected Methyl Red-degrading Microbial Isolates --- p.138 / Chapter 4.3.1 --- "Monitoring of Percentage of Methyl Red Cleaved and Degradation Value of N,N-Dimethyl-p-phenylene diamine and o-Aminobenzoic acid and Growth of Selected Methyl Red- degrading Bacterial Isolates by Spectrophotometric Analysis " --- p.138 / Chapter 4.3.2 --- Study of Degradation Products of Methyl Red by Selected Methyl Red-degrading Isolates by HPLC --- p.175 / Chapter 4.4 --- Degradation of Other Azo Dyes by Selected Methyl Red-degrading Isolates --- p.175 / Chapter 5. --- Discussion --- p.181 / Chapter 5.1 --- "Isolation, Selection and Characterization of Methyl Red-degrading and N,N-dimethyl-p-phenylene diamine-degrading Microbial Isolates " --- p.181 / Chapter 5.1.1 --- "Isolation and Selection of Methyl Red-degrading Microbes from Dye-containing Wastewater, Activated Sludge and Soil " --- p.181 / Chapter 5.1.2 --- "Isolation and Selection of N,N-Dimethyl-p-phenylene diamine- degrading Microbial Isolates from Dye-containing Wastewater, Activated Sludge and Soil " --- p.183 / Chapter 5.1.3 --- Identification of the Selected Methyl Red-degrading and N,N- Dimethyl-p-phenylene diamine-degrading Bacteria --- p.185 / Chapter 5.1.4 --- Correlationship of Dry Weight and Absorbance of Cells of Selected Methyl Red-degrading Bacterial Isolates --- p.185 / Chapter 5.2 --- "Characterization of Methyl Red, N,N-Dimethyl-p-phenylene diamine and o-Aminobenzoic acid " --- p.186 / Chapter 5.2.1 --- "Chemical Stability of Methyl Red, N,N-Dimethyl-p-phenylene diamine and o-Aminobenzoic acid in 0.05 M phosphate buffer and 0.2MHC1 " --- p.186 / Chapter 5.2.2 --- "Change of UV-Vis Spectra of Methyl Red and N,N-Dimethyl-p- phenylene diamine at Different pH and Matrixes " --- p.187 / Chapter 5.2.3 --- "Change of UV-Vis Spectra of N,N-Dimethyl-p-phenylene diamine in Different Matrixes at Different pH " --- p.187 / Chapter 5.2.4 --- "UV-Vis Spectra and Standard Curve of Methyl Red, N,N- dimethyl-p-phenylene diamine and o-Aminobenzoic acid " --- p.188 / Chapter 5.2.5 --- "HPLC Separation of Methyl Red, N,N-Dimethyl-p-phenylene diamine and o-Aminobenzoic acid " --- p.189 / Chapter 5.3 --- Methyl Red Degradation by Selected Methyl Red-degrading Microbial Isolates --- p.190 / Chapter 5.3.1 --- Effect of Glucose --- p.194 / Chapter 5.3.2 --- Effect of Ethanol --- p.196 / Chapter 5.3.3 --- Effect of Ammonium Sulphate --- p.198 / Chapter 5.3.4 --- Effect of Yeast Extract --- p.199 / Chapter 5.3.5 --- Effect of Phosphate Buffer (pH 7) --- p.200 / Chapter 5.3.6 --- Effect of pH --- p.201 / Chapter 5.3.7 --- Effect of Temperature at Static and Shaking Conditions --- p.203 / Chapter 5.3.8 --- Study of Degradation Products of Methyl Red by Selected Methyl Red-degrading Isolates by HPLC Analysis --- p.206 / Chapter 5.4 --- Degradation of Other Azo Dyes by Selected Methyl Red-degrading Isolates --- p.207 / Chapter 6. --- Conclusion --- p.209 / Chapter 7. --- References --- p.213 / Chapter 8. --- Appendix 1: Composition of Media --- p.222 / Appendix 2: Composition of Buffers --- p.225 / Appendix 3 --- p.228
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Forensic animal necrophagy in the South-West of Western Australia : species, feeding patterns and taphonomic effectsO'Brien, R. Christopher January 2008 (has links)
[Truncated abstract] One of the standard ways of assessing time since death is from the stages of decomposition of the body. It is well known that the rate of decomposition is affected by environmental factors such as temperature and humidity. Another factor that can affect decompositional rates is the presence of breaches in the protective barrier of the skin, whether arising from antemortem injury or postmortem damage, including that occurring from animal necrophagy. Scavengers have the potential to affect decomposition by breaching the skin allowing access to associated insect material, feeding on the maggot masses, or by consumption of the carcass itself. Each locality will have its own set of features determining the rate of decomposition of the body, and variation may occur within localities based on the seasons. Such variation implies the need for local calibration of time since death against degree of decomposition and to establish the magnitude of interseasonal variation. When the localities are outdoors, the influence of potential scavengers, and the factors affecting their activity need also to be taken into account. This study investigates the interaction of environmental factors and animal scavenging on the rate of decomposition of pig (Sus scrofa) carcasses at four south-west Western Australia sites; Jandakot, Shenton Park, Perup Forest, and Watheroo National Park. Jandakot and Shenton Park are both close to the Perth metropolitan area and the western coast while Perup Forest is southern and inland and Watheroo is northern and inland. ... The most common insectivore feeding in relation to the carcasses was the Willie Wagtail (Rhipidura leucophrys) which was associated with the carcasses in all seasons and all locations except for Perup Forest. The breeding cycle appeared to have a marked influence on the intensity of scavenging by several species. The effect of season on decompositional rates was greatly reduced in carcasses that were exposed to scavenging. It took no additional time for carcasses to achieve skeletonization in winter than in the other seasons in the presence of scavenging. Scavenging had no significant impact on the rate of breakdown of carcasses in summer, when decompositional rates were greatest and scavenging at a minimum. v In Western Australia, it is not uncommon for bodies to remain undiscovered in bush environments for lengthy periods of time due to the low human population density. This study shows conclusively that it is not sufficient simply to consider the accumulated degree day (ADD) when estimating time since death by the degree of decomposition of the body. Attention must also be given to local wildlife assemblages and variations in their activities with the seasons. The implications of this research are in the determination of time of death. If the effects of scavengers accelerate decomposition this must be taken into account when any calculation since time of death is determined. The marked variations between sites in the rates of decomposition of carcasses exposed to natural animal scavenging in this study highlights the need for local calibration of time since death to decompositional stages for all locales. The techniques devised in this study are straight forward and easily conducted yet are informative and essential in determining time since death for bodies which have been exposed to animal scavenging.
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DNA degradation and repair in Escherichia coli following UV irradiation/Fong, Kenneth Shui-yuen January 1977 (has links)
This document only includes an excerpt of the corresponding thesis or dissertation. To request a digital scan of the full text, please contact the Ruth Lilly Medical Library's Interlibrary Loan Department (rlmlill@iu.edu).
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Biodegradability of resilon, a resin based root canal obturating material, by typical endodontic pathogensRexford, Ashleigh M. January 2012 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Root canal therapy is a recommended treatment for apical periodontitis. Root canal failure can occur as a result of microbial leakage. Resilon, a resin based root canal obturating cone material introduced in 2004 attempts to minimize leakage by a unique bonding method of the resin sealer to both the core material and to the dentin of the canal walls. Resilon has no bactericidal or antimicrobial effect15. Furthermore, it has been shown that Resilon is susceptible to alkaline and enzymatic hydrolysis as well as bacterial degradation.73, 184-186 It has been suggested that Resilon may be susceptible to degradation by microorganisms found in the infected root canal space. This work focuses on the susceptibility of root canal obturating materials to be degraded by endodontic pathogens seen in root canal treated teeth with apical periodontitis. The aim of this study was to determine if Resilon could be degraded by selected pathogenic bacteria found in the infected root canal system, and if this degradation is more severe than with gutta-percha, a conventional obturating material.
P. intermedia, E. faecalis and P. aeruginosa, known endodontic pathogens were inoculated on discs of obturating material (Resilon or gutta-percha) mounted on a platform and placed in wells containing TSB incubated at 37°C under aerobic conditions. The discs were polished, examined by SEM, profilometry, and elemental analysis prior to inoculation to establish a baseline, and were then re-examined by these methods one month after inoculation. The overall results were inconclusive; and using these methods it cannot be determined that the selected bacteria can degrade Resilon. An ideal future study would utilize SEM with gold coated samples as well as atomic force microscopy to evaluate for changes in topographical features of these obturating materials. A notable finding was that Resilon turns black when exposed to bacteria, and the significance of this finding should be addressed in future studies.
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Soil aquifer treatment of artificial wastewater under saturated conditionsEssandoh, Helen M.K., Tizaoui, Chedly, Mohamed, Mostafa H.A., Amy, G., Brdjanovic, D. January 2011 (has links)
A 2000 mm long saturated laboratory soil column was used to simulate soil aquifer treatment under saturated conditions to assess the removal of chemical and biochemical oxygen demand (COD and BOD), dissolved organic carbon (DOC), nitrogen and phosphate, using high strength artificial wastewater. The removal rates were determined under a combination of constant hydraulic loading rates (HLR) and variable COD concentrations as well as variable HLR under a constant COD. Within the range of COD concentrations considered (42 mg L(-)(1)-135 mg L(-)(1)) it was found that at fixed hydraulic loading rate, a decrease in the influent concentrations of dissolved organic carbon (DOC), biochemical oxygen demand (BOD), total nitrogen and phosphate improved their removal efficiencies. At the high COD concentrations applied residence times influenced the redox conditions in the soil column. Long residence times were detrimental to the removal process for COD, BOD and DOC as anoxic processes and sulphate reduction played an important role as electron acceptors. It was found that total COD mass loading within the range of 911 mg d(-)(1)-1780 mg d(-)(1) applied as low COD wastewater infiltrated coupled with short residence times would provide better effluent quality than the same mass applied as a COD with higher concentration at long residence times. The opposite was true for organic nitrogen where relatively high concentrations coupled with long residence time gave better removal efficiency.
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Removal of dissolved organic carbon and nitrogen during simulated soil aquifer treatmentEssandoh, Helen M.K., Tizaoui, Chedly, Mohamed, Mostafa H.A. January 2013 (has links)
Soil aquifer treatment was simulated in 1 m laboratory soil columns containing silica sand under saturated and unsaturated soil conditions to examine the effect of travel length through the unsaturated zone on the removal of wastewater organic matter, the effect of soil type on dissolved organic carbon removal and also the type of microorganisms involved in the removal process. Dissolved organic carbon removal and nitrification did enhance when the wastewater travelled a longer length through the unsaturated zone. A similar consortium of microorganisms was found to exist in both saturated and unsaturated columns. Microbial concentrations however were lowest in the soil column containing silt and clay in addition to silica sand. The presence of silt and clay was detrimental to DOC removal efficiency under saturated soil conditions due to their negative effect on the hydraulic performance of the soil column and microbial growth.
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Analytical method development for the identification, detection, and quantification of emerging environmental contaminants in complex matricesPlace, Benjamin J. 15 August 2013 (has links)
The development of analytical methods for emerging contaminants creates many unique challenges for analytical chemists. By their nature, emerging contaminants have inherent data gaps related to their environmental occurrence, fate, and impact. This dissertation is a compilation of three studies related to method development for the structural identification of emerging contaminants, the detection and quantification of chemicals used in unprecedented quantities and applications, and the extraction of compounds from complex matrices where the solvent-solute-matrix interactions are not completely understood. The three studies present analytical methods developed for emerging contaminants in complex matrices, including: fluorochemical surfactants in aqueous film-forming foams, oil dispersant surfactants in seawater, and fullerene nanomaterials in carbonaceous solids.
Aqueous film-forming foams, used in military and commercial firefighting, represent environmentally-relevant commercial mixtures that contain a variety of fluorochemical surfactants. Combining the surfactant-selective ionization of fast atom bombardment mass spectrometry with high resolution mass spectrometry, chemical formulas for 11 different fluorochemical classes were identified. Then AFFF-related patents were used to determine the structures. Of the eleven classes of fluorochemicals, ten have little, if any, data on their environmental occurrence, fate, and potential impacts in the peer-reviewed literature. In addition, nine of the identified classes had either cationic or zwitterionic functionalities and are likely to have different transport properties compared to the well-studied anionic fluorochemicals, such as perfluorooctanoate.
After the Deepwater Horizon oil spill in the summer of 2010, one of the emergency response methods for the mitigation of the oil's environmental impact was the use of unprecedented amounts of oil dispersant to break down the oil slick and encourage biodegradation. This event illustrated the need for rapid analytical method development in order to respond to the potential environmental disaster in a timely manner. Using large volume injection liquid chromatography with tandem mass spectrometry, an analytical method was developed for the trace analysis of the multiple dispersant surfactant classes and the potential degradation products of the primary surfactant. Limits of detection ranged from 49 ��� 3,000 ng/L. The method provided excellent recovery (86 ��� 119%) and precision (10 ��� 23% RSD), while also accommodating for the high salinity of seawater samples and analyte contamination.
Despite the fact that fullerene nanomaterials have been studied for almost three decades, research is still being conducted to fully understand the environmental properties of these materials. Previous studies to extract fullerenes from environmental matrices have resulted in low efficiency, high variability, or the extraction efficiencies have gone unreported. Extraction by ultrasonication with toluene and 1-methylnaphthalene increased the recovery 5-fold of a spiked, isotopically-labeled C������ surrogate from carbon lampblack as compared to that of the conventional approach of extracting with 100% toluene. The study revealed the importance of evaluating experimental variables such as extraction solvent composition and volume, and sample mass, as they have a significant impact on the quantitative extraction of fullerenes from environmental matrices. / Graduation date: 2013 / Access restricted to the OSU Community at author's request from Aug. 15, 2012 - Aug. 15, 2013
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