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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.
11

Use of spent mushroom compost of pleurotus pulmonarius as a source of ligninolytic enzymes for organopollutant degradation.

January 2004 (has links)
Tsang Yiu-Yuen. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 198-218). / Abstracts in English and Chinese. / Abstract --- p.i / 摘要 --- p.iii / Acknowledgments --- p.v / Table of contents --- p.vi / List of figures --- p.xi / List of tables --- p.xvi / Abbreviations --- p.xviii / Chapter 1. --- Introduction / Chapter 1.1 --- Organic pollutant and environment --- p.1 / Chapter 1.2 --- Polycyclic aromatic hydrocarbon --- p.3 / Chapter 1.2.1 --- Distributions and treatment standards of two target PAHs --- p.5 / Chapter 1.3 --- Pentachlorophenol --- p.8 / Chapter 1.3.1 --- Distribution and treatment standard of PCP --- p.10 / Chapter 1.4 --- Dichlorodiphenyltrichloroethane --- p.12 / Chapter 1.4.1 --- Distribution and treatment standard of DDT --- p.13 / Chapter 1.5 --- Indigo carmine --- p.15 / Chapter 1.6 --- Cleanup technologies towards organopollutants --- p.16 / Chapter 1.6.1 --- Treatment methods for organopollutants --- p.16 / Chapter 1.6.2 --- Enzyme technology on environmental cleanup --- p.18 / Chapter 1.6.3 --- Oxidoreductase --- p.19 / Chapter 1.6.4 --- Enzyme preparation --- p.20 / Chapter 1.6.5 --- Spent mushroom compost --- p.21 / Chapter 1.6.5.1 --- Laccase --- p.22 / Chapter 1.6.5.2 --- Catalytic cycle of laccase --- p.23 / Chapter 1.6.5.3 --- Lignin peroxidase --- p.25 / Chapter 1.6.5.4 --- Catalytic cycle of LiP --- p.26 / Chapter 1.6.5.5. --- Manganese peroxidase --- p.27 / Chapter 1.6.5.6 --- Catalytic cycle of MnP --- p.28 / Chapter 1.6.6 --- Limitations on enzyme technology --- p.29 / Chapter 1.6.7 --- Enhancement of laccase activity and/or catalytic lifetime --- p.30 / Chapter 1.6.8 --- Enhancement of MnP activity and/or catalytic lifetime --- p.32 / Chapter 1.6.9 --- Other general approaches to maintain enzyme activity --- p.34 / Chapter 1.7 --- Aims of my study --- p.35 / Chapter 2. --- Materials and Methods / Chapter 2.1 --- Materials --- p.36 / Chapter 2.1.1 --- Production of spent mushroom compost (SMC) --- p.36 / Chapter 2.2 --- Effect of age and batches of SMCs on enzyme qualities --- p.37 / Chapter 2.3 --- Maximization of enzymes extracted from SMC --- p.38 / Chapter 2.3.1 --- Effect of extraction solution type --- p.38 / Chapter 2.3.2 --- Effect of extraction volume --- p.39 / Chapter 2.3.3 --- Effect of extraction time --- p.39 / Chapter 2.3.4 --- Effect of rotation speed --- p.39 / Chapter 2.4 --- Enzyme and protein quality --- p.39 / Chapter 2.4.1 --- Protein assay --- p.39 / Chapter 2.4.2 --- Laccase assay --- p.40 / Chapter 2.4.3 --- Manganese peroxidase assay --- p.40 / Chapter 2.4.4 --- Lignin peroxidase assay --- p.41 / Chapter 2.4.5 --- p-glucanase assay --- p.41 / Chapter 2.4.6 --- Carboxymethylcellulase assay --- p.42 / Chapter 2.4.7 --- Xylanase assay --- p.42 / Chapter 2.4.8 --- Lipase assay --- p.43 / Chapter 2.4.9 --- Protease assay --- p.43 / Chapter 2.5 --- Freeze-drying on crude enzyme preparation --- p.44 / Chapter 2.5.1 --- Effect of freeze-drying --- p.44 / Chapter 2.6 --- Partial purification on crude enzyme preparation --- p.44 / Chapter 2.6.1 --- PAGE analyses on Pleurotus SMC's laccase and MnP --- p.44 / Chapter 2.6.2 --- Effect of dialysis --- p.45 / Chapter 2.7 --- Characterization of crude enzyme powder --- p.46 / Chapter 2.7.1 --- Metal analysis --- p.46 / Chapter 2.7.2 --- Anion contents --- p.47 / Chapter 2.7.3 --- H202 content --- p.47 / Chapter 2.8 --- Stability of crude enzyme at storage --- p.48 / Chapter 2.9 --- Optimization of crude enzyme activities --- p.48 / Chapter 2.9.1 --- Ligninolytic enzyme --- p.48 / Chapter 2.9.1.1 --- Crude enzyme amount --- p.48 / Chapter 2.9.1.2 --- pH effect --- p.49 / Chapter 2.9.1.3 --- Temperature effect --- p.49 / Chapter 2.9.1.4 --- EDTA addition --- p.49 / Chapter 2.9.1.5 --- Copper ion addition --- p.49 / Chapter 2.9.1.6 --- Manganese ion addition --- p.50 / Chapter 2.9.1.7 --- Hydrogen peroxide addition --- p.50 / Chapter 2.9.1.8 --- Malonic acid addition --- p.50 / Chapter 2.9.2 --- "Other enzymes (beta-glucanase, carboxymethylcellulase and xylanase)" --- p.51 / Chapter 2.9.2.1 --- Temperature effect --- p.51 / Chapter 2.9.2.2 --- pH effect --- p.51 / Chapter 2.10 --- Studies on the degradation ability of crude enzyme towards organopollutants --- p.51 / Chapter 2.10.1 --- Removal of PAH (naphthalene and phenanthrene) --- p.52 / Chapter 2.10.1.1 --- Experimental setup --- p.52 / Chapter 2.10.1.2 --- Effect of PAH concentration --- p.53 / Chapter 2.10.1.3 --- Effect of ABTS addition --- p.54 / Chapter 2.10.1.4 --- Effect of incubation time --- p.54 / Chapter 2.10.1.5 --- Putative identification and quantification of PAHs --- p.54 / Chapter 2.10.2 --- Removal of pentachlorophenol --- p.56 / Chapter 2.10.2.1 --- Experimental setup --- p.56 / Chapter 2.10.2.2 --- Effect of PCP concentration --- p.57 / Chapter 2.10.2.3 --- Effect ofABTS addition --- p.57 / Chapter 2.10.2.4 --- Effect of incubation time --- p.57 / Chapter 2.10.2.5 --- Putative identification and quantification of PCP --- p.57 / Chapter 2.10.3 --- "Removal of 4,4´ة-DDT" --- p.58 / Chapter 2.10.3.1 --- Experimental setup --- p.58 / Chapter 2.10.3.2 --- Effect of DDT concentration --- p.59 / Chapter 2.10.3.3 --- Effect ofABTS addition --- p.59 / Chapter 2.10.3.4 --- Effect of incubation time --- p.59 / Chapter 2.10.3.5 --- Putative identification and quantification of DDT --- p.60 / Chapter 2.10.4 --- Removal of dye ´ؤ Indigo carmine --- p.61 / Chapter 2.10.4.1 --- Experimental setup --- p.61 / Chapter 2.10.4.2 --- Effect of dye concentration --- p.62 / Chapter 2.10.4.3 --- Effect of ABTS addition --- p.62 / Chapter 2.10.4.4 --- Effect of incubation time --- p.62 / Chapter 2.11 --- Assessment criteria --- p.62 / Chapter 2.11.1 --- Degradation ability --- p.62 / Chapter 2.11.2 --- Toxicity of treated samples (Microtox® test) --- p.63 / Chapter 2.12 --- Statistical analysis --- p.64 / Chapter 3. --- Results / Chapter 3.1 --- The best SMC for enzyme preparation --- p.65 / Chapter 3.2 --- Maximization of enzymes extracted from SMC --- p.72 / Chapter 3.2.1 --- Effect of extraction solution type and volume on crude enzyme recovery --- p.72 / Chapter 3.2.2 --- Effect of extraction time on crude enzyme recovery --- p.79 / Chapter 3.2.3 --- Effect of rotation speed on crude enzyme recovery --- p.79 / Chapter 3.3 --- Effect of dialysis on crude enzyme preparation --- p.82 / Chapter 3.4 --- Freeze-drying on crude enzyme preparation --- p.82 / Chapter 3.5 --- Characterization of crude enzyme powder --- p.86 / Chapter 3.6 --- Optimization of crude enzyme activities --- p.87 / Chapter 3.7 --- Storage stability of crude enzyme in powder form and liquid form --- p.115 / Chapter 3.8 --- Studies on degradation ability of crude enzyme towards organopollutants --- p.135 / Chapter 3.8.1 --- Degradation of naphthalene (NAP) by crude enzyme solution --- p.135 / Chapter 3.8.2 --- Degradation of phenanthrene (PHE) by crude enzyme solution. --- p.141 / Chapter 3.8.3 --- Degradation of pentachlorphenol (PCP) by crude enzyme solution --- p.147 / Chapter 3.8.4 --- "Degradation of 4,4´ة-DDT by crude enzyme solution" --- p.152 / Chapter 3.8.5 --- Degradation of Indigo carmine by crude enzyme solution --- p.158 / Chapter 4. --- Discussion / Chapter 4.1 --- The best SMC for enzyme preparation --- p.163 / Chapter 4.2 --- Maximization of ligninolytic enzymes extracted from SMC --- p.168 / Chapter 4.2.1 --- Effect of extraction solution type and volume on crude enzyme recovery --- p.168 / Chapter 4.2.2 --- Effect of extraction time on crude enzyme recovery --- p.169 / Chapter 4.2.3 --- Effect of rotation speed on crude enzyme recovery --- p.169 / Chapter 4.3 --- Effect of dialysis on crude enzyme extract --- p.171 / Chapter 4.4 --- Freeze-drying on crude enzyme extract --- p.171 / Chapter 4.5 --- Characterization of crude enzyme powder --- p.172 / Chapter 4.6 --- Optimization of crude enzyme activities --- p.173 / Chapter 4.6.1 --- Effect of crude enzyme amount --- p.173 / Chapter 4.6.2 --- Effect of incubation pH --- p.174 / Chapter 4.6.3 --- Effect of incubation temperature --- p.176 / Chapter 4.6.4 --- Effect of EDTA addition --- p.177 / Chapter 4.6.5 --- Effect of copper and manganese ion addition --- p.177 / Chapter 4.6.6 --- Effect of hydrogen peroxide addition --- p.179 / Chapter 4.6.7 --- Effect of malonic acid on maintaining enzyme activities --- p.180 / Chapter 4.6.8 --- Activities and stabilities of ligninolytic enzymes under the combined optimal conditions --- p.181 / Chapter 4.7 --- Storage stability of crude enzyme in powder form and liquid form --- p.182 / Chapter 4.7.1 --- "β-glucanase, carboxymethylcellulase (CMCase) and xylanase activities" --- p.182 / Chapter 4.7.2 --- Protein content --- p.182 / Chapter 4.7.3 --- Laccase activity --- p.183 / Chapter 4.7.4 --- MnP activity --- p.183 / Chapter 4.8 --- Studies on the degradation ability of crude enzyme towards organopollutants --- p.185 / Chapter 4.8.1 --- Degradation of naphthalene (NAP) by crude enzyme solution --- p.185 / Chapter 4.8.2 --- Degradation of phenanthrene (PHE) by crude enzyme solution. --- p.187 / Chapter 4.8.3 --- Degradation of pentachlorophenol (PCP) by crude enzyme solution --- p.189 / Chapter 4.8.4 --- "Degradation of 4,4-DDT by crude enzyme solution" --- p.190 / Chapter 4.8.5 --- Degradation of Indigo carmine by crude enzyme solution --- p.191 / Chapter 4.9 --- Prospect for SMC as a source of organopollutant-degrading enzyme --- p.193 / Chapter 5. --- Conclusions --- p.195 / Chapter 6. --- Further Investigation --- p.197 / Chapter 7. --- References --- p.198
12

Composting as a bioremediation technology for remediation of PAHs contaminated soil

Wan, Cheung Kuen 01 January 2000 (has links)
No description available.
13

Remediation of trace metal contaminated soils

Tejowulan, Raden Sri. January 1999 (has links)
No description available.
14

Bioremediation of low-permeability, pentachlorophenol-contaminated soil by laboratory and full-scale processes

Havighorst, Mark B. 30 January 1998 (has links)
Ex-situ bioremediation of saturated soil contaminated with pentachlorophenol and 2,3,5,6-TeCP is commonly accomplished by landfarming or by treatment in a bioreactor. Treating saturated, low-permeability soils in bioreactors, without pre-treatment requires a reactor capable of promoting anaerobic and/or aerobic removal of chlorophenols without transferring these contaminants to the aqueous phase. A pilot-scale bioreactor was designed to treat 3.7 cubic meters of contaminated soil with a saturated hydraulic conductivity of 0.12 cm/day. The bioreactor demonstrated significant removal of chlorophenols when soil was infused with a treatment mixture containing imitation vanilla flavoring as an electron donor for reductive dechlorination and primary substrate for aerobic cometabolism. Bench scale studies showed greater overall removal when feed mixtures included an inoculated biomass, or when treatment mixtures were maintained anaerobically prior to use. The combined results of these studies suggest that concentrations of pentachlorophenol and 2,3,5,6-TeCP in soil can be significantly reduced using fill and draw batch reactors, operated for three to five week long cycles, using a variety of treatment mixtures. / Graduation date: 1998
15

The plant soil interface nickel bioavailability and the mechanisms of plant hyperaccumulation /

McNear, David H. January 2006 (has links)
Thesis (Ph.D.)--University of Delaware, 2006. / Principal faculty advisor: Donald L. Sparks, Dept. of Plant & Soil Science. Includes bibliographical references.
16

Groundwater remediation at a former oil service site

Han, Liping 29 August 2005 (has links)
As an intern with URS Corporation, I participated in several remediation and wastewater treatment projects during the year 2004. A groundwater remediation project was selected to present in this record of study for my Doctor of Engineering degree not only because I spent more time on it than any other project, but also because it represents the broadness and depth of a typical URS remediation project. In this report, findings from previous environmental investigations were summarized and used for computer modeling and remediation strategy evaluation. Computer models were used to simulate site conditions and assist in remedy design for the site. Current pump-and-treat systems were evaluated by the model under various scenarios. Recommendations were made for the pump-and-treat system to control the contaminant plume. Various remediation technologies were evaluated and compared for their applicability at the site. A combination of on-site remediation and downgradient plume control was chosen as the site remediation strategy. Treatability studies and additional modeling work are needed for the remediation system design and optimization.
17

Mathematical simulation of a dipole delivery system for in-situ remediation

Huo, Chao 19 February 2010 (has links)
Abstract In-situ remediation using reactive zones is a promising groundwater contaminant treatment technology that involves the injection of a reagent(s) into the subsurface to destruct harmful target chemicals. For efficient and effective treatment the reagent has to be delivered into a specific contaminated zone for the desired chemical reaction(s) to occur. The most commonly used delivery method is a conventional well where the distribution of injected reagent is mainly controlled by the surrounding hydraulic conductivity field. In this case, the reagent is easily delivered into the higher hydraulic conductivity zones but the lower hydraulic conductivity zones are missed. The goal of this research effort is to investigate a novel delivery method involving a single well vertical recirculation system or a dipole well. The configuration of this single dipole well is that injection and extraction occurs from two chambers separated by an impermeable central packer. Thus, this dipole well system can induce predominantly vertical flow across bedding plane features and it is therefore hypothesised that this delivery system can overcome physical heterogeneities creating a more uniform reactive zone. The objective of this research was to demonstrate that the dipole well is a useful delivery tool compared to the commonly used single injection well. Mathematical simulations were used to investigate the delivery performance of a dipole well using steady-state and transient approaches. A simple analytical model was used to determine the steady-state dipole flow field and observe the impact of system parameters on reagent delivery behaviour. The size of coverage area (the area swept by the injected reagent) was used as the performance metric to assess the impact of each system parameter on the dipole well performance. Numerical simulations were used to extend this investigation to homogeneous and heterogeneous (structured or randomly correlated hydraulic conductivity) aquifers under pulsed operation to identify those situations where the dipole delivery system is more efficient or effective. Both forward and backward particle path lines were used to identify reagent coverage areas around the injection well and down gradient. The impact of each system parameters on the dipole well performance was studied. The shoulder length and the injection cost are characteristic parameters that affect dipole delivery performance. A relationship between the down gradient coverage area vs. characteristic system parameters was developed and can be used to predict the dipole well performance in homogenous aquifers. The impact of the hydraulic conductivity distribution on dipole well performance is consistent with either a structured hydraulic conductivity field or randomly correlated hydraulic conductivity fields. Regions of lower hydraulic conductivity can be swept by the dipole well and the dipole well outperforms a single injection well, which is analyzed as a base case in terms of the shape of down gradient coverage area. However, the advantage of dipole well over a single well delivery is small if the degree of heterogeneity is large or the horizontal extent of the bedding plane is small.
18

Mathematical simulation of a dipole delivery system for in-situ remediation

Huo, Chao 19 February 2010 (has links)
Abstract In-situ remediation using reactive zones is a promising groundwater contaminant treatment technology that involves the injection of a reagent(s) into the subsurface to destruct harmful target chemicals. For efficient and effective treatment the reagent has to be delivered into a specific contaminated zone for the desired chemical reaction(s) to occur. The most commonly used delivery method is a conventional well where the distribution of injected reagent is mainly controlled by the surrounding hydraulic conductivity field. In this case, the reagent is easily delivered into the higher hydraulic conductivity zones but the lower hydraulic conductivity zones are missed. The goal of this research effort is to investigate a novel delivery method involving a single well vertical recirculation system or a dipole well. The configuration of this single dipole well is that injection and extraction occurs from two chambers separated by an impermeable central packer. Thus, this dipole well system can induce predominantly vertical flow across bedding plane features and it is therefore hypothesised that this delivery system can overcome physical heterogeneities creating a more uniform reactive zone. The objective of this research was to demonstrate that the dipole well is a useful delivery tool compared to the commonly used single injection well. Mathematical simulations were used to investigate the delivery performance of a dipole well using steady-state and transient approaches. A simple analytical model was used to determine the steady-state dipole flow field and observe the impact of system parameters on reagent delivery behaviour. The size of coverage area (the area swept by the injected reagent) was used as the performance metric to assess the impact of each system parameter on the dipole well performance. Numerical simulations were used to extend this investigation to homogeneous and heterogeneous (structured or randomly correlated hydraulic conductivity) aquifers under pulsed operation to identify those situations where the dipole delivery system is more efficient or effective. Both forward and backward particle path lines were used to identify reagent coverage areas around the injection well and down gradient. The impact of each system parameters on the dipole well performance was studied. The shoulder length and the injection cost are characteristic parameters that affect dipole delivery performance. A relationship between the down gradient coverage area vs. characteristic system parameters was developed and can be used to predict the dipole well performance in homogenous aquifers. The impact of the hydraulic conductivity distribution on dipole well performance is consistent with either a structured hydraulic conductivity field or randomly correlated hydraulic conductivity fields. Regions of lower hydraulic conductivity can be swept by the dipole well and the dipole well outperforms a single injection well, which is analyzed as a base case in terms of the shape of down gradient coverage area. However, the advantage of dipole well over a single well delivery is small if the degree of heterogeneity is large or the horizontal extent of the bedding plane is small.
19

Groundwater remediation at a former oil service site

Han, Liping 29 August 2005 (has links)
As an intern with URS Corporation, I participated in several remediation and wastewater treatment projects during the year 2004. A groundwater remediation project was selected to present in this record of study for my Doctor of Engineering degree not only because I spent more time on it than any other project, but also because it represents the broadness and depth of a typical URS remediation project. In this report, findings from previous environmental investigations were summarized and used for computer modeling and remediation strategy evaluation. Computer models were used to simulate site conditions and assist in remedy design for the site. Current pump-and-treat systems were evaluated by the model under various scenarios. Recommendations were made for the pump-and-treat system to control the contaminant plume. Various remediation technologies were evaluated and compared for their applicability at the site. A combination of on-site remediation and downgradient plume control was chosen as the site remediation strategy. Treatability studies and additional modeling work are needed for the remediation system design and optimization.
20

In situ chemical oxidation schemes for the remediation of ground water and soils contaminated by chlorinated solvents

Li, Xuan. January 2002 (has links)
Thesis (Ph. D.)--Ohio State University, 2002. / Title from first page of PDF file. Document formatted into pages; contains xv, 179 p.; also contains graphics (some col.). Includes abstract and vita. Advisor: Franklin W. Schwartz, Dept. of Geosciences. Includes bibliographical references (p. 172-179).

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