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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.
371

Trace element concentrations in mangrove sediments in the Sundarbans, Bangladesh

Awal, M.A., Hale, William H.G., Stern, Ben January 2009 (has links)
No / Peoples' Republic of Bangladesh and the Asian Development Bank (ADB)
372

The role of suspended matter on trace metal transport in an estuarine environment

Nance, Stephen William 08 1900 (has links)
No description available.
373

Heavy metal accumulation and biomarkers in environmental monitoring of contaminated coastal sediments.

January 2005 (has links)
Tang Wai Lun. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 199-220). / Abstracts in English and Chinese. / Abstract --- p.ii / 摘要 --- p.iv / Acknowledgements --- p.vi / Table of contents --- p.vii / List of Abbreviations --- p.xi / List of Tables --- p.xii / List of Figures --- p.xv / Chapter Chapter One --- Literature Review --- p.1 / Chapter 1.1 --- Marine pollution in Hong Kong --- p.1 / Chapter 1.2 --- Contamination of sediments --- p.3 / Chapter 1.2.1 --- Metals contamination in coastal sediments in Hong Kong --- p.4 / Chapter 1.2.2 --- Other contaminants in sediments --- p.7 / Chapter 1.3 --- Sediment toxicity assessment --- p.9 / Chapter 1.4 --- Fish as examples for the measurement of biological responses to contaminants --- p.9 / Chapter 1.5 --- Biomarkers for toxicity assessment --- p.11 / Chapter 1.5.1 --- Metallothionein (MT) --- p.11 / Chapter 1.5.2 --- Cytochrome P450 1A (CYP1A) --- p.13 / Chapter 1.5.3 --- Vitellogenin (Vtg) --- p.13 / Chapter 1.5.4 --- Enzyme biomarkers: Alanine transaminase (ALT); aspartate transaminase (AST) and creatine kinase (CK) --- p.14 / Chapter 1.5.5 --- DNA damage detected by the comet assay --- p.16 / Chapter 1.6 --- Multi biomarkers for sediment toxicity assessments --- p.16 / Chapter 1.7 --- Objectives --- p.16 / Chapter Chapter Two --- "Concentrations of Heavy Metals and Trace Organics in Coastal Sediments Collected from Victoria Harbour, Deep Bay, Tolo Harbour and Lai Chi Wo" --- p.18 / Chapter 2.1 --- Introduction --- p.18 / Chapter 2.2 --- Materials and Methods --- p.19 / Chapter 2.2.1 --- Sediment collection --- p.19 / Chapter 2.2.2 --- Treatment of sediment samples --- p.21 / Chapter 2.2.3 --- Acid wash of apparatus --- p.21 / Chapter 2.2.4 --- Acid digestion of sediment sample --- p.21 / Chapter 2.2.5 --- Sequential extraction of heavy metals in sediment samples --- p.22 / Chapter 2.2.6 --- Heavy metals measurement --- p.23 / Chapter 2.2.7 --- Trace organic measurement in sediments --- p.24 / Chapter 2.2.8 --- Statistical Analysis --- p.24 / Chapter 2.3 --- Results --- p.25 / Chapter 2.3.1 --- Concentrations of total Metals in sediments --- p.25 / Chapter 2.3.2 --- Speciation of metals in sediments --- p.27 / Chapter 2.3.3 --- Metal abundance in different fractions of sediment --- p.33 / Chapter 2.3.4 --- Concentrations of trace organic in sediments --- p.33 / Chapter 2.3.5 --- Results summary --- p.36 / Chapter 2.4 --- Discussion --- p.36 / Chapter 2.4.1 --- Comparison with international standards --- p.38 / Chapter 2.4.2 --- Comparison with international studies of coastal sediments --- p.39 / Chapter 2.4.3 --- Comparison of the present study with other studies concerning Hong Kong coastal sediments --- p.45 / Chapter Chapter Three --- "Heavy Metals Accumulation in Tissues of Tilapia Exposed to Coastal Sediments Collected from Victoria Harbour, Deep Bay, Tolo Harbour, and Lai Chi Wo" --- p.51 / Chapter 3.1 --- Introduction --- p.51 / Chapter 3.2 --- Materials and Methods --- p.52 / Chapter 3.2.1 --- Collection and treatment of coastal sediments --- p.52 / Chapter 3.2.2 --- Sediment exposure tests with Tilapia --- p.53 / Chapter 3.2.3 --- Dissection of fish samples --- p.54 / Chapter 3.2.4 --- Acid digestion of fish samples --- p.54 / Chapter 3.2.5 --- Statistical Analysis --- p.55 / Chapter 3.3 --- Results --- p.55 / Chapter 3.3.1 --- Metal accumulation --- p.55 / Chapter 3.3.2 --- "Dose, duration and source of sediments affecting metals uptake" --- p.95 / Chapter 3.3.3 --- Results summary --- p.99 / Chapter 3.4 --- Discussion --- p.99 / Chapter 3.4.1 --- Site comparison --- p.99 / Chapter 3.4.2 --- Comparison with other studies --- p.100 / Chapter 3.4.3 --- Safety limits --- p.112 / Chapter Chapter Four --- "Expression of Biomarker Genes (MT, CYP1 A, Vtg) in Tissues of Male Tilapia After Eexposure to Coastal Sediments Collected from Victoria Harbour, Deep Bay, Tolo Harbour and Lai Chi Wo" --- p.115 / Chapter 4.1 --- Introduction --- p.115 / Chapter 4.2 --- Materials and Methods --- p.116 / Chapter 4.2.1 --- Sample collection --- p.116 / Chapter 4.2.2 --- Preparation of apparatus --- p.117 / Chapter 4.2.3 --- mRNA expression analysis --- p.117 / Chapter 4.2.3.1 --- Isolation of RNA --- p.117 / Chapter 4.2.3.2 --- Reverse transcription --- p.118 / Chapter 4.2.3.3 --- Real time PCR --- p.118 / Chapter 4.2.4 --- Vitellogenin (Vtg) --- p.120 / Chapter 4.2.5 --- Statistics analysis --- p.121 / Chapter 4.3 --- Results --- p.121 / Chapter 4.3.1 --- MT mRNA expression in tissues of male Tilapia exposed to sediments --- p.121 / Chapter 4.3.2 --- CYP1A mRNA expression in tissues of male Tilapia exposed to sediments --- p.129 / Chapter 4.3.3 --- Vtg expression in tissues of male Tilapia exposed to sediments --- p.137 / Chapter 4.3.4 --- Dose and time dependent relationships --- p.137 / Chapter 4.3.5 --- Results summary --- p.137 / Chapter 4.4 --- Discussion --- p.142 / Chapter 4.4.1 --- Correlation of MT and CYP1A expression with metals uptake in gills and liver --- p.142 / Chapter 4.4.2 --- MT as a biomarker of metals exposure --- p.144 / Chapter 4.4.3 --- CYP1A as a biomarker of trace organics exposure --- p.145 / Chapter 4.4.4 --- Real-time PCR --- p.147 / Chapter 4.4.5 --- Vtg as a biomarker of xenoestrogen exposure --- p.147 / Chapter Chapter Five --- "Expression of Enzyme Biomarkers (ALT, AST and CK) in Tissues of Male Tilapia After Exposure to Coastal Sediments Collected From Victoria Harbour, Deep Bay, Tolo Harbour and Lai Chi Wo" --- p.149 / Chapter 5.1 --- Introduction --- p.149 / Chapter 5.2 --- Materials and Methods --- p.150 / Chapter 5.2.1 --- Samples collection --- p.150 / Chapter 5.2.2 --- Alanine transaminase (ALT) and Aspartate transaminase (AST) --- p.151 / Chapter 5.2.3 --- Creatine kinase (CK) --- p.152 / Chapter 5.2.4 --- Statistical analysis --- p.153 / Chapter 5.3 --- Results --- p.153 / Chapter 5.3.1 --- ALT --- p.153 / Chapter 5.3.2 --- AST --- p.157 / Chapter 5.3.3 --- CK in gills --- p.157 / Chapter 5.3.4 --- CK in muscle --- p.164 / Chapter 5.3.5 --- "Dose, duration and source of sediments affecting metals uptake" --- p.164 / Chapter 5.3.6 --- Results summary --- p.169 / Chapter 5.4 --- Discussion --- p.169 / Chapter Chapter Six --- "DNA Damage in Liver of Male Tilapia After Exposure to Coastal Sediments Collected from Victoria Harbour, Deep Bay, Tolo Harbour and Lai Chi Wo" --- p.174 / Chapter 6.1 --- Introduction --- p.174 / Chapter 6.2 --- Materials and Methods --- p.176 / Chapter 6.2.1 --- Samples collection --- p.176 / Chapter 6.2.2 --- Tissue Preparation --- p.176 / Chapter 6.2.3 --- Single Cell Gel Electrophoresis (Comet) Assay --- p.176 / Chapter 6.2.4 --- Image analysis --- p.177 / Chapter 6.2.5 --- Statistical analysis --- p.178 / Chapter 6.3 --- Results --- p.180 / Chapter 6.4 --- Discussion --- p.187 / Chapter Chapter Seven --- General Discussion and Conclusion --- p.190 / Chapter 7.1 --- General discussion --- p.190 / Chapter 7.2 --- Conclusion --- p.198 / References --- p.199 / Appendix --- p.221
374

Geophysical studies of sediments in waters near Hong Kong and in the Gulf of St. Lawrence

Wong, How-Kin., 黃孝建. January 1967 (has links)
published_or_final_version / Physics / Doctoral / Doctor of Philosophy
375

Gas production from hydrate-bearing sediments:geo-mechanical implications

Jung, Jongwon 10 November 2010 (has links)
Gas hydrate consists of guest gas molecules encaged in water molecules. Methane is the most common guest molecule in natural hydrates. Methane hydrate forms under high fluid pressure and low temperature and is found in marine sediments or in permafrost region. Methane hydrate can be an energy resource (world reserves are estimated in 20,000 trillion m3 of CH4), contribute to global warming, or cause seafloor instability. Research documented in this thesis starts with an investigation of hydrate formation and growth in the pores, and the assessment of formation rate, tensile/adhesive strength and their impact on sediment-scale properties, including volume change during hydrate formation and dissociation. Then, emphasis is placed on identifying the advantages and limitations of different gas production strategies with emphasis on a detailed study of CH4-CO2 exchange as a unique alternative to recover CH4 gas while sequestering CO2. The research methodology combines experimental studies, particle-scale numerical simulations, and macro-scale analyses of coupled processes.
376

Gas hydrate formation in Gulf of Mexico sediments

Dearman, Jennifer L., January 2007 (has links)
Thesis (Ph.D.)--Mississippi State University. Dave C. Swalm School of Chemical Engineering. / Title from title screen. Includes bibliographical references.
377

Deciphering Phosphorus and Aluminum Physiochemical Associations in Paleolake Sediments of Long Pond, GA

Tidwell, Christopher 12 August 2016 (has links)
This study focuses on Long Pond, a groundwater-fed sinkhole lake in Georgia, which does not exhibit any evidence of eutrophication drivers despite high concentrations of sedimentary phosphorus (P) (> 3000 mg/kg P) in the recent sediment record. Chemical analyses have shown a strong correlation (r2>0.99) between P and aluminum (Al) throughout the core, suggesting Al plays a significant role in sequestering most of the P, and limiting its availability to phytoplankton, thereby inhibiting eutrophication. The purpose of this study is to decipher P and Al physicochemical associations in the sediments. After the samples were fractionated into amorphous and non-amorphous phases, the correlation was maintained in both phases. Evidence suggests two modes of Al-P associations: a sorption and/or co-precipitation occurring mostly in the amorphous phase and a mode whereby Al and P are being inputted to the lake bound together.
378

Sedimentology of Estero Marua, Sonora, Mexico

Sandusky, Clinton LeRoy, 1942- January 1969 (has links)
No description available.
379

Sediment and solute loads in a small Hong Kong stream

霍年亨, Fok, Lincoln. January 2001 (has links)
published_or_final_version / Geography and Geology / Master / Master of Philosophy
380

Autotrophic denitrification in nitrate-induced marine sediment remediation

Shao, Mingfei., 邵明非. January 2009 (has links)
published_or_final_version / Civil Engineering / Doctoral / Doctor of Philosophy

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