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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.
31

Sorption of heavy metals on a hydrous manganese oxide

Loganathan, Paripurnananda, January 1971 (has links)
Thesis (Ph. D.)--University of California, Davis, 1971. / Includes bibliographical references (leaves 131-146).
32

Evaluation of the impact of contaminant on trace metal content of compost

Zhou, Lixian. January 2010 (has links)
Thesis (M. Sc.)--University of Alberta, 2010. / Title from pdf file main screen (viewed on June 18, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science in Environmental Engineering, Department of Civil and Environmental Engineering, University of Alberta. Includes bibliographical references.
33

Approaches to assess heavy metal toxicity in the marine environment /

Fung, Chi-tuen. January 2006 (has links)
Thesis (M. Sc.)--University of Hong Kong, 2006.
34

METAL ACCUMULATION AND ABUNDANCE OF TURTLES ON THE WEST KENTUCKY WILDLIFE MANAGEMENT AREA/DOE PADUCAH GASEOUS DIFFUSION PLANT COMPLEX

Yu, Shuangying 01 December 2009 (has links)
Heavy metals have been detected in aquatic and terrestrial environment around the Paducah Gaseous Diffusion Plant (PGDP). However, little is known regarding their accumulation and associated effects in turtles inhabiting aquatic ecosystems near the PGDP. The current study was initiated to evaluate accumulation of heavy metals and its associated effects in aquatic turtle species and to determine species composition and abundance in ponds near the PGDP. A total of 382 turtles composed of 6 species were captured at 6 ponds during 2007 and 2008. Red-eared slider turtles (Trachemys scripta elegans) were the most abundant species (81.2% of the total number of turtles captured), and the abundance and densities ranged from 12 to 88 turtles and from 39 to 122 turtles/ha among study ponds, respectively. Only Cu concentrations in liver tissue differed among ponds, which may be associated with the age of one study pond. However, a gradient of increasing concentrations from ponds upstream to ponds midstream and downstream of the PGDP was observed for Pb and Hg in liver. Copper and Hg were detected in red-eared slider eggs. Copper concentrations in eggs were positively correlated with female Cu concentrations in kidney. Metal concentrations in turtle tissues and sediment were lower than previously reported concentrations associated with adverse effects. Total white blood cell counts, ratios of heterophils to lymphocytes, numbers of lymphocytes and eosinophils, and T-cell mediated immunity were correlated with metal concentrations. Hematocrits were not correlated with any metal concentrations in any tissues. Hemoparasites were observed in 40.7% of the red-eared slider turtles studied. Concentrations of heavy metals in turtle tissues, eggs, and sediment measured in the current study were low, and are not thought to be adversely affecting aquatic turtles near the PGDP. Although some hematological and immunological indices were correlated with some metal concentrations, further studies are needed to determine if these effects are associated with metal exposure, with hemoparasites, or other contaminants or disease.
35

Mercury accumulation by the eelpout (Zoarces vivparus L.) in the Forth Estuary, Scotland

Mathieson, Scot January 1993 (has links)
No description available.
36

Copper, lead and zinc sorption on Wyoming montmorillonite

Cooper, Roger Brian January 1976 (has links)
Exchange adsorption of Cu²⁺ , Pb²⁺ and Zn²⁺ for Na on Wyoming mont-morillonite, in chloride and nitrate electrolyte solutions less than 10⁻³ M total heavy metal concentration, can be modelled with a simple equilibrium ion-exchange reaction: Me²⁺ + 2 Na{Mont} = Me{Mont}₂ + 2 Na⁺ where Me. and Mont represent a given heavy metal and montmorillonite. Equilibrium constants for this reaction are equal for Cu²⁺ and Zn²⁺ at 3.0 ± 1, slightly less than that for Pb²⁺ at 5.0 ± 1, and comparable to constants calculated for monopositive exchange of K⁺ for Na⁺ (3.0 ± 1) and H⁺ for Na⁺ (2.5 ± .5). Above 10⁻³ M total metal concentration, heavy metal exchange for Na is complicated by variable total Na exchange capacity and by apparent anionic interferences. CuCl₂ and ZnCl₂ electrolyte solutions are more effective Na exchangers at 0.1 M than Cu(NO₃)₂, Pb(NO₃)₂, KC1 or HC1 solutions at the same concentration. Retardation factors of Cu, Pb and Zn spots eluted across thin layers of Na-montmorillonite (supported by silica gel) by aqueous NaCl and NaNO₃ solutions of 0.05 to 3.0 M concentration suggest, when interpreted with a rudimentary ion-exchange mass transfer model, that metals migrate mainly as monopositive species—perhaps as monohydroxo-complexes within the clay micelle. Precipitation of Pb chloride or hydroxy-chloride is indicated by multiple Pb spots on NaCl-eluted chromatograms. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
37

The removal of heavy metals from municipal wastewaters by lime-magnesium coagulation

MacLean, Byard H. January 1977 (has links)
The evidence of heavy metal build up in the aquatic environment near sewage treatment plant outfalls around Vancouver,coupled with the generally held theory that secondary treatment is not required in this area, leads to the conclusion that a treatment method is required that is primarily aimed at heavy metal removal. In this study, jar tests were performed to evaluate the heavy metal removal efficiency of the lime-magnesium coagulation process. Five heavy metals (Cr³⁺ , Cu²⁺ , Pb²⁺ , Ni²⁺ and Zn²⁺ ) were all tested at initial concentrations of .5, 2.5 and 5.0 mg/1 individually and in combination. The experiments were performed on prechlorinated primary effluent and raw sewage at the natural alkalinity levels (120-130 mg/1 as CaCO₃), and some work was done at elevated alkalinity (190-200 mg/1). The need for filtration in the process was also researched. Results of the study indicated that the heavy metal removal efficiency was enhanced by the presence of Mg²⁺ at a given lime dosage for all of the heavy metals except nickel. A comparison indicated that intermediate lime treatment (220 mg/1) coupled with 33 mg/1 Mg²⁺ might be a more attractive process than just straight high lime treatment (400 mg/1). / Applied Science, Faculty of / Civil Engineering, Department of / Graduate
38

A study of the toxic effects and binding capacity for the heavy metals cadmium, copper, and zinc by the blue-green alga Chroococcus paris.

Les, Albin Paul 01 January 1983 (has links) (PDF)
No description available.
39

Phytoremediation of contaminated soil from a petroleum refinery land treatment unit

Gomez, Katherine Emma 03 December 2001 (has links)
No description available.
40

Heavy metal accumulation in free and immobilized pseudomonas picketti.

January 1990 (has links)
by Li Sze Kwan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1990. / Bibliography: leaves 234-259. / ACKNOWLEDGEMENT --- p.i / ABSTRACT --- p.ii / CONTENTS : / Chapter CHAPTER 1: --- GENERAL INTRODUCTION --- p.1 / Chapter 1.1 --- Our Environment Is Polluted --- p.1 / Chapter 1.2 --- Heavy Metal Contamination --- p.3 / Chapter 1.3 --- The Effect of Cadmium and Some Related Metals on Environment --- p.5 / Chapter 1.4 --- The Uses of Microorganisms in Cleaning Up Environment --- p.9 / Chapter 1.5 --- Mechanisms of Cadmium Uptake in Cadmium Accumulating Strains --- p.10 / Chapter 1.6 --- Techniques for Cell Immobilization --- p.13 / Chapter 1.7 --- Prospect --- p.20 / Chapter CHAPTER 2: --- ISOLATION OF CADMUIM ACCUMULATNIG MICROORGANISMS --- p.22 / Chapter 2.1 --- Introduction --- p.22 / Chapter 2.2 --- Materials and Methods --- p.25 / Chapter 2.2.1 --- Recipes Used for Growing Various Organisms --- p.25 / Chapter 2.2.2 --- Methods Used for Collecting Organisms to be Tested --- p.27 / Chapter 2.2.3 --- Observation of Samples by Microscope --- p.28 / Chapter 2.2.4 --- Enrichment of Cadmium Resistant Microorganisms --- p.28 / Chapter 2.2.5 --- Selection and Isolation of Cadmium Resistant Microorganisms --- p.29 / Chapter 2.2.6 --- Purification of Microbial Colonies --- p.30 / Chapter 2.2.7 --- Preliminary Classification of Selected Microorganisms --- p.30 / Chapter 2.2.8 --- Screening of Cadmium Accumulating Strains --- p.30 / Chapter 2.2.9 --- Cadmium Analysis --- p.31 / Chapter 2.3 --- Result --- p.32 / Chapter 2.3.1 --- Selection of Cadmium Resistant --- p.32 / Chapter 2.3.2 --- Cadmium Resistance of Isolates --- p.36 / Chapter 2.3.3 --- Screening of Cadmium Accumulating Microorganisms --- p.38 / Chapter 2.4 --- Discussion --- p.39 / Chapter CHAPTER 3: --- GENERAL CHARACTERIZATION OF STRAIN 1000A --- p.43 / Chapter 3.1 --- Introduction --- p.43 / Chapter 3.1.1 --- Various Factors Affecting the Accumulation of Cadmium of Strain 1000A --- p.43 / Chapter 3.1.2 --- Identification --- p.44 / Chapter 3.2 --- Materials and Methods --- p.45 / Chapter 3.2.1 --- "Preparation of Solutions, Antibiotics and Reagents" --- p.45 / Chapter 3.2.2 --- Culture Media Used --- p.47 / Chapter 3.2.3 --- Growth Kenetics Determination --- p.48 / Chapter 3.2.4 --- Determination of the Effect of Cadmium Concentration on Cd-uptake in Free Cells --- p.49 / Chapter 3.2.5 --- Determination of the Effect of Phosphate Concentration on Cd-uptake in Free Cell --- p.49 / Chapter 3.2.6 --- Determination of the Cd-uptake in Free Cells in Continuous Cultures --- p.50 / Chapter 3.2.7 --- Determination of Antibiotic Resistance of Strain 1000A --- p.51 / Chapter 3.2.8 --- Dstermination of Relationship between Chloramphenicol Resistance and Cd-uptake --- p.52 / Chapter 3.2.9 --- Cadmium Analysis --- p.52 / Chapter 3.2.10 --- Determination of Inorganic Precipitation of Cadmium --- p.53 / Chapter 3.2.11 --- Assimilation Tests --- p.54 / Chapter 3.2.12 --- Identification of Strain 1000A --- p.55 / Chapter 3.3 --- Result --- p.55 / Chapter 3.3.1 --- Growth Kinetics of Strain 1000A in Cadmium Supplemented Peptone Medium --- p.55 / Chapter 3.3.2 --- Cd-uptake of Strain 1000A at Various Cadiuin Concentration --- p.65 / Chapter 3.3.3 --- Effect of Phosphate concentration on Cd-uptake of Strain 1000A --- p.65 / Chapter 3.3.4 --- Cd-uptake of Strain 1000A in Continuous Cultures --- p.70 / Chapter 3.3.5 --- Inorganic Precipitation of Cadmium Phosphate --- p.75 / Chapter 3.3.6 --- Determination of Antibiotic-Resistance of Strain 1000A --- p.78 / Chapter 3.3.7 --- Effect of Chloramphenicol on Cd-uptake and Cadmium Resistance of Strain 1000A --- p.82 / Chapter 3.3.8 --- Determination of the Effect of Tetracyclin --- p.85 / Chapter 3.3.9 --- Assimilation Tests --- p.94 / Chapter 3.3.10 --- Identification of Strain 1000A --- p.94 / Chapter 3.4 --- Discussion --- p.97 / Chapter CHAPTER 4: --- DETERMINATION OF CADMIUM UPTAKE MECHANISM IN P. PICKETTI 1000A --- p.102 / Chapter 4.1 --- Introduction --- p.102 / Chapter 4.2 --- Materials and Methods --- p.105 / Chapter 4.2.1 --- Preparation of Solutions and Reagents --- p.105 / Chapter 4.2.2 --- Preparation of Reagents for SDS-PAGE --- p.105 / Chapter 4.2.3 --- Recipes for Growing Cells --- p.107 / Chapter 4.2.4 --- Protein Determination --- p.108 / Chapter 4.2.5 --- Examination of Cadmium Accommodation in P. picketti 1000A by Transmission Electron Microscope --- p.108 / Chapter 4.2.6 --- SDS-polyacrylamide Gel Electrophoretic Determination of Protein Profiles --- p.109 / Chapter 4.2.7 --- Phosphate Assay --- p.111 / Chapter 4.2.8 --- Orthophosphate Estimation --- p.112 / Chapter 4.2.9 --- Sulphide Analysis --- p.112 / Chapter 4.2.10 --- Cadmium Analysis --- p.113 / Chapter 4.2.11 --- Cd-binding Determination through Column Separation --- p.113 / Chapter 4.2.12 --- Cd-binding Determinate ion through SDS Electrophoresis --- p.114 / Chapter 4.2.13 --- Determination of Cadmium Distribution of Cells --- p.115 / Chapter 4.3 --- Result --- p.116 / Chapter 4.3.1 --- SDS-PAGE Determination of Protein Profiles of P. picketti 1000A --- p.116 / Chapter 4.3.2 --- Determination of Cd-binding Protein of P. picketti 1000A --- p.121 / Chapter 4.3.3 --- "Determination of the Relationship of Cellular Cadmium, Sulphide and Phosphate" --- p.131 / Chapter 4.3.4 --- Examination of Cadmium Accumulation of P. picketti 1000A by Transmission Electron Microscope --- p.142 / Chapter 4.3.5 --- Cadmium Distribution of Cadmium-Accommodated Cells --- p.148 / Chapter 4.4 --- Discussion --- p.152 / Chapter CHAPTER 5: --- CORRELATION AMONG METALS IN HEAVY METAL UPTAKE --- p.158 / Chapter 5.1 --- Introduction --- p.158 / Chapter 5.2 --- Materials and Methods --- p.158 / Chapter 5.2.1 --- Preparation of Solutions --- p.159 / Chapter 5.2.2 --- "Determination of Effect of Zn+2 ," --- p.160 / Chapter 5.2.3 --- Determination of Effect of Cu+2 . --- p.161 / Chapter 5.2.4 --- "Correlation among Cd+2, Cu+2 and Zn+2" --- p.161 / Chapter 5.2.5 --- Growth Kenetics Determination --- p.162 / Chapter 5.2.6 --- Cell Sample Preparation --- p.162 / Chapter 5.2.7 --- Orthophosphate Estimation --- p.162 / Chapter 5.2.8 --- Metal Analysis --- p.163 / Chapter 5.3 --- Result --- p.163 / Chapter 5.3.1 --- Effect of Zn+2 --- p.163 / Chapter 5.3.2 --- Effect of Cu+2 --- p.173 / Chapter 5.3.3 --- "Correlation among Cd+2, Cu+2 and Zn+2" --- p.178 / Chapter 5.4 --- Discussion --- p.195 / Chapter CHAPTER 6: --- HEAVY METAL UPTAKE OF IMMOBILIZED CELL --- p.197 / Chapter 6.1 --- Introduction --- p.197 / Chapter 6.2 --- Materials and Methods --- p.199 / Chapter 6.2.1 --- Preparation of Solutions and Medium --- p.199 / Chapter 6.2.2 --- Harvesting of Cells --- p.199 / Chapter 6.2.3 --- Immobilization of Cells --- p.199 / Chapter 6.2.4 --- Determination of the Effect of Temperature --- p.200 / Chapter 6.2.5 --- Determination of Optimum Cell Concentration in Polyacrylamide Gel --- p.201 / Chapter 6.2.6 --- Determination of pH Effect on Cd-uptake --- p.201 / Chapter 6.2.7 --- Pretreatment with 70% Methanol --- p.202 / Chapter 6.2.8 --- Combined Pretreatment with Methanol and NaOH --- p.202 / Chapter 6.2.9 --- Effect of Phosphate on Cd-uptake of Immobilized Cell --- p.202 / Chapter 6.2.10 --- Comparison of Cadmium- and Copper-uptakes in Cells Immobilized in K-carrageenan and in Polyacrylamide --- p.203 / Chapter 6.3 --- Result --- p.204 / Chapter 6.3.1 --- Effect of Temperature on Cd-uptake --- p.204 / Chapter 6.3.2 --- Determination of Optimum Cell Concentration in Polyacrylamide Gel --- p.204 / Chapter 6.3.3 --- Effect of pH on Cd-uptake of Immobilized Cells --- p.207 / Chapter 6.3.4 --- Effect of Methanol on Cd-uptake --- p.210 / Chapter 6.3.5 --- Combined Effect of pH and Methanol on Cd-uptake --- p.213 / Chapter 6.3.6 --- Effect of Phosphate on Cd-uptake of Immobilized Cells --- p.213 / Chapter 6.3.7 --- Comparison between Cadmium- and Copper-uptake of Cells Immobilized in K-carrageenan and in Polyacrylamide --- p.220 / Chapter 6.4 --- Discussion --- p.228 / Chapter CHAPTER 7: --- CONCLUSION --- p.232 / REFERENCES --- p.234

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