Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 187 for “"metal concentrations"”.
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Prediction of Mississippi-Valley type ore fluid metal concentrations from solid solution metal concentrations in ore-stage minerals
… to form MVT deposits is knowledge of their concentrations in the ore fluids. Recent research aimed at determining the concentrations of Pb, Zn, and Ba in the ore fluids that formed the MVT deposits of the U.S. midcontinent, the type examples for the MVT deposit class, has focused on using …
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Trace Metal Concentrations across Trophic Levels in Cotton Fields of Xinjiang Province, China
<p>Trace metals become concentrated in urban and peri-urban soils with the use of agricultural practices and industrial emissions. Fertilizers, liming, sewage sludge, and irrigation water contain metals which accumulate in agricultural fields and pose a risk to humans and wildlife. Coal plants and …
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An Assessment of Heavy Metal Concentrations in Surface Sediments from the Knysna Estuary
… sediment samples in respect of total heavy metal concentrations, sediment grain size, and total organic carbon within 36 surface sediment samples from the Ashmead Channel in the Knysna Estuary. 15 surface sediment samples were also analysed from Chongming Island in the Yangtze Estuary of the …
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Heavy Metal Concentrations in Springs and Sinkholes in and Around Springfield, Greene County, Missouri
… purpose of this study is to determine if heavy metals are present in springs and sinkholes located in and around Springfield, Greene County, Missouri. Water suspended solid samples were collected from eight springs including Ritter East (RE), Ritter West (RW), Jones (J), Sequiota (SQ), Silver …
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Heavy Metal Concentrations in Stream Sediments Adjacent to the Greenfield Sanitary Landfill, Dade County, Missouri
… placed in sanitary landfills contain heavy metals believed to be toxic or cause environmental degradation. The purpose of this study is to determine if heavy metals are entering Wetzel Branch, a stream running adjacent to the closed landfill. The very fine sand fraction of sixty sediment …
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Heavy metal concentrations, primary productivity, chlorophyll-a levels, and the autotrophic indices of stream periphyton subjected to wood preservation waste
… Water samples were analyzed for the three metals; arsenic, chromium, and copper. The highest mean periphyton arsenic and chromium concentration occurred at the station 1.2 miles below the site of contamination. The copper concentration in the periphyton was highest 2.7 miles below the area …
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Characterization of Metal Concentrations in Sediment and Water of the Swan Creek Watershed, A Major Tributary in the Maumee River Area of Concern
… Board, due in part to the presence of heavy metal and organic chemical sediment contamination detrimental to the overall quality of the Great Lakes. The primary objective of this study is to determine current level of metals in water and sediment from Swan Creek, to identify those areas that …
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Determination of metal concentrations in vegetation, soil, dust, and water in the vicinity of a cement factory in North West province, South Africa
… study was to quantify a selected number of trace metal concentrations in vegetation, soil , dust and water samples near a cement manufacturing pl ant in the North West Province. Thirty-one samples at various distances from approximately 500m to 2700m from where the cement factory is situated, were …
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Assessment of heavy metal concentrations in water and sediment of dams in Central Namibia and bioaccumulation of copper in locally occuring crabs and fish
… which can lead to accumulation of heavy metals in aquatic systems. Mining activities in the Karstveld, specifically in the Tsumeb-Grootfontein-Otavi area, may potentially result in heavy metal pollution of water sources. A seasonal study was conducted to assess the concentration of heavy …
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Heavy metal concentrations, aging techniques and population characteristics of mink in Virginia: with a review of the literature on delayed implantation in the mink
Lead, cadmium, zinc and copper concentrations were determined in bone, kidney and liver samples of mink (Mustela vison) trapped during 1981-83 in Virginia. Ages were determined to obtain population information. The literature on delayed implantation in mink was reviewed. Lead and cadmium …
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LITERATURE REVIEW: The Use of Cation-Exchange Resins in Natural Water Trace Metals Research. ARTICLE: Determination of Free Ion Trace Metal Concentrations in Freshwaters Using Cation-Exchange Resin Equilibrium. A Preliminary Investigation.
LITERATURE REVIEW: The desire to measure low metal concentrations in natural waters stems principally from the aim to understand the effects of trace metals on aquatic biota and to understand the fate of metal pollutants. Trace metals rarely exist in the free ion form, with distribution of the …
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Heavy Metal Content in Stream Sediments Adjacent to the Warren County, Missouri Landfill Complex
… absorption techniques were used to determine the concentrations of Cu, Cd, Pb, Zn, Ni, Co, Mn, Ag, Fe, and Cr in sediments of Indian Camp Creek. Results indicated mean metal concentrations increased near the landfill complex. A t-test indicated Cu, Cd, Pb, Zn, Ni, Co, Mn, Ag, and Fe exceeded the …
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Sources of variability in trace metal bioaccumulation by fish
… and channel catfish were collected in 1982 from metal-contaminated Peak Creek, Virginia. Whole-body and tissue concentrations of cadmium, lead, and zinc were determined by atomic absorption spectrophotometry. Variations in metal concentrations within each species were related to duration of …
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Bioaccessibility of Metals in Soils of Parks and Playgrounds – Fort McMurray, Alberta
… the concentration and bioaccessibility of metals present in soils at parks and playgrounds in Fort McMurray, Alberta. Sixty soil samples collected from 20 parks and playgrounds were analyzed for pH, total metal concentration by X-ray fluorescence. In addition, in vitro bioaccessibility …
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Passerine Exposure to Metal Contaminants from Oilsands Mining in the Athabasca Region of Northeastern Alberta, Canada
I characterized passerine exposure to metals from waste-materials associated with oilsands mining. I measured metal concentrations in whole blood of tree swallows (Tachycineta bicolor), Tennessee warblers (Oreothlypis peregrina), and chipping sparrows (Spizella passerina). Additionally, I measured …
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Levels of Heavy Metals in Sediment Samples from Select Creeks in Metro Vancouver, BC, Canada
… physicochemical properties in surface water and metal concentrations in sediments. The pH, total dissolved solids and electrical conductivity in surface water samples ranged from 5.50 to 8.27, 14.0 to 410.0 ppm, and 19.0 to 903.0 µS/cm, respectively, with no discernible relationship between the …
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Dynamics of heavy metals in reedbeds along the banks of the river Scheldt
… was assessed, to be able to predict potential metal accumulation in controlled flooding areas and new wetlands. Moreover, the most important factors that affect metal accumulation and mobility in these marshes were identified. The superficial intertidal sediment layer was found to be …
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Bioaccessibility of metals in soils in selected parks in Montreal
The main focus of this study was to determine the concentrations and bioaccessibility of metals in Montreal city parks. Surface soil samples were collected from nine parks located across Montreal city and analyzed for total metals, pH, carbon content and bioaccessibility. Metal concentrations were …
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