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 29 for “"concentrations of metals"”.
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A Dendrochemical Analysis of Lead, Aluminum, and Calcium in Southern Appalachian American Beech.
<p>The health of the northern hardwood forest in the Southern Appalachian Mountains of Tennessee, North Carolina, and Virginia has recently gained attention from the media and environmental stakeholders. This project was designed to examine concentrations of metals, including lead, aluminum, and …
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The effects of a toxic metals spill on aquatic fauna in streams near Culpeper, Virginia
The event which prompted this study was a spill of two hundred thousand gallons of chromium-arsenic-copper solution from a holding pond into an adjacent, first-order stream on January 31, 1981. The holding pond, owned by Culpeper Wood Preservers Company of Culpeper, Virginia, was used to store …
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Concentrations and In Vitro Bioaccessibility of Metals in Soils at Urban Green Spaces in Toronto, Ontario
This study investigated metal concentrations and pH in 75 soil samples obtained from 25 urban green spaces within the City of Toronto. In vitro bioaccessibility was determined in eight of the samples as a surrogate for bioavailability. The mean concentrations of metals of interest, As, Cr, Cu, Ni, …
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Assessing the Risks Posed by Metal Contamination to Environmental and Human Health in Millstream Creek, Canada
… race cars at an abandoned raceway in the region of Millstream-Langford on Vancouver Island is hypothesized to pose a risk to environmental and human health. This thesis uses Millstream Creek in the City of Langford as the study region for assessing whether the concentration of metals in sediment …
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Levels of Heavy Metals in Sediment Samples from Select Creeks in Metro Vancouver, BC, Canada
… 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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Distribution of Metals in Soils in Public Parks in South Calgary
AbstractThe concentrations of metals in 60 soil samples from 19 playgrounds across the southwest and southeast quadrants of Calgary were determined by x-ray fluorescence. The mean metal concentrations were below the Canadian Council of Ministers of the Environment soil quality guidelines for …
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An evaluation of a modified membrane filter technique for the recovery of fecal coliforms exposed to selected heavy metals
… fecal coliforms exposed to selected heavy metals. The effects on recovery by increasing time and metal concentration were also examined. The recovery methods employed included the standard membrane filter technique (S-MF) and a modified membrane filter technique (M-MF)~ which consisted of a …
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Assessing Industrial Contamination of Brockport Creek After Removal of Contaminated Sediment
This project assessed the condition of Brockport Creek and a tributary following removal of contaminated sediment from the tributary in 2002. Before the cleanup, PCB concentrations in sediments ranged from 1, 730 to 34,900 µg/kg; after the cleanup they ranged from 288 to 432 µg/kg, below water …
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Heavy metal pollution and blackheaded gull (larus ridibundus L.) breeding ecology
Heavy metals in air, soil and water are a global problem and present a growing threat to the environment. These metals may have profound consequences for birds and can cause a number of sub-lethal effects, such as decreased reproductive success. The concentrations of selected heavy metals (As, Cd. …
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Evaluation of Metal Concentration in Water and Soil in the Southern Region of Lake Nacogdoches
<p>The concentrations of metals (Ba, Cd, Co, Cr, Cu, Mn, Ni, Pb, Sr, V, Zn) were investigated in soil and water samples collected over four different sites in the southern part of Lake Nacogdoches over one year from August 2018 through June 2019. Water samples were analyzed using the USEPA method …
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Particle Size Distribution Analysis of a Mining-Impacted Gravel-Bed Stream in Ohio Using a Hybrid Sediment Sampling Technique
As part of a risk assessment study of the Leading Creek Watershed in Ohio, a prior Virginia Tech researcher collected pavement and subpavement sediment samples at 17 sites using the hybrid areal sampling technique with a clay adhesive. The watershed, which is heavily impacted by mining and …
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Development of Leaching Processes for the Recovery of Rare Earth Elements from Acid Mine Drainage Precipitates
… regulation in the US that requires the treatment of AMD before water can be discharged into the environment. AMD is generated when sulfide minerals are exposed to water and air from mining. The acidic water then leaches metals from the surrounding rock, creating the potential for environmental …
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Development and application of field methods for determination of the extent of acid mine drainage contamination and geochemical characteristics of stream sediment recovery
… surface and ground waters through the generation of acidic mine drainage (AMD). Introduced metals typically are deposited from the water column onto the stream bed downstream of the AMD input(s). The drivers of metal deposition onto stream sediments are through either the formation of insoluble …
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Assessment of flagellate diversity at deep-sea hydrothermal vents using the combined approach of culture-dependent and culture-independent methods
Eighteen strains of flagellated protists representing 9 species were isolated and cultured from four deep-sea hydrothermal vents in the Eastern Pacific Ocean: Juan de Fuca Ridge, Guaymas Basin, and both 21°N and 9°N on the East Pacific Rise (EPR). The hydrothermal vent flagellates belonged to six …
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Relationships between water quality, species composition, biodiversity and ecosystem function in lakes and flooded pits exposed to uranium mining activities in Northern Saskatechewan
… impact aquatic systems through mine drainage (runoff) and the release of treated effluent into nearby watersheds. Such anthropogenic exposure can lead to elevated concentrations of metals and major ions, which may impact aquatic biota. Previous studies have looked at the effects of water quality …
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Characterization of the intraspecific variation within the nickel (Ni) hyperaccumulator species Senecio coronatus (Asteraceae): a preliminary analysis of genetic population structure and shoot proteome expression
… hyperaccumulate and detoxify exceptionally high concentrations of metals in their aboveground tissues, without exhibiting any apparent signs of toxicity. Despite nickel (Ni) hyperaccumulator plants representing the largest percentage of known metal accumulator taxa (over 75%), the underlying …
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Investigating metal exposure on the general populace of the copper mining town of Kitwe, Zambia
… mining contributes to significant elevated metals in the environment, hence increasing the risk of metals exposure to human populations living in and around mining areas. Recent research has focused on the environmental impact of copper mining byproducts such as lead, cadmium, copper, cobalt …
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Analisis kandungan logam berat (Cd Dan Hg) dan struktur histologi insang pada kerang darah (Anadara granosa) di Pantai Bangil Kabupaten Pasuruan
… situation is quite alarming as it gets the flow of waste from industrial centers Bangil and Rembang, which is alleged to have contaminated coastal areas of heavy metal. Waste is likely to contain toxic and hazardous chemicals. One of the waste is estimated to contain heavy metals Cd and Hg. This …
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Metals and polycyclic aromatic hydrocarbons in environmental matrices of the Fleet Lagoon, UK and toxicological investigations using the marine polychaete Hediste diversicolor.
… environment is ubiquitous and may contain both metals and polycyclic aromatic hydrocarbons (PAH’s) individually or within complex mixtures. Contamination may bind directly to organic particles within sediment and may remain undisturbed or re-released during periods of hydrodynamic activity. …
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A metals study to assess human health risks in drinking water from Eastport, Perry, and Pleasant Point, Maine
This study analyzed drinking water for a subset of health concerns expressed by residents in the towns of Eastport, Perry, and Pleasant Point. The town of Pleasant Point is located in the Passamaquoddy tribe's reservation, and all three towns are located in the Boyden Lake watershed in Maine. Water …
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