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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.
81

An examination of selected trace elements in modern and ancient samples of Triticum spelta

Langston, Joy January 1994 (has links)
Analyses were made of concentrations of six elements (the micronutrients copper, iron, manganese and zinc, and the macronutrients calcium and magnesium) in samples of Triticum spetta and the soil they were grown on to investigate relationships between the two, and the possibility of sourcing material found in the archaeological record. Charred and fresh grains of geographically and geologically diverse locations were broken down in nitric acid using a microwave digestion technique. The resultant solutions were analysed by atomic absorption spectroscopy. Soil extractions using nitric acid and diethylene triamine penta-acetic acid allowed analyses of total and available elements. The results of soil / grain digests were investigated but no consistently significant relationships could be discerned. Growth experiments were performed by growing grain samples from various locations on one soil type to assess which factors were primarily important in elemental uptake. Calcium and magnesium uptake appears strongly influenced by the growing environment, but that of the micronutrients is additionally affected by genetic factors. In order to assess changes in elemental concentration due to burial, diagenetic experiments were carried out using grain from various locations and a series of differing burial periods. It was found that there was a trend for concentrations of the micronutrients and magnesium to decrease, whilst calcium concentrations increased substantially. On completion of work with modem grain, samples from the archaeological record were analysed. Elemental concentrations were found to be very different in ancient material and more significantly related to the burial environment. It appears possible to differentiate between leached, rural and waterlogged/urban sites.
82

Trace elements in a porphyry copper deposit by atomic absorption spectrometry

Jeon, Gyoo Jeong January 1983 (has links)
This study concerns the origin of a porphyry copper deposit. For the study 25 rock samples were taken from a porphyry copper deposit. Rock samples were analyzed for these trace elements: strontium, barium, copper, zinc, and vanadium. The results indicated that elevation correlations are not apparent for copper, zinc, and vanadium content, but definite correlations appear between strontium and barium content. This study determined that strontium is one of the trace elements which could be used as a possible exploration guide to porphyry copper mineralization. This study also provided that distribution of trace elements demonstrates the presence of a regional difference in the strontium and barium contents of the sample locations between the Dome Peak Quadrangle area and the Agnes Mountain area of the Cloudy Pass batholith; the volcanics of the former possess higher levels of strontium and barium concentrations.
83

Adsorptive stripping voltammetry of trace elements on a glassy carbon mercury film electrode /

Pablo, Fleurdelis. January 1994 (has links)
Thesis (Ph.D)--University of Western Sydney, Nepean, 1994. / Includes bibliography.
84

Hydride generation and laser spectroscopy techniques for trace analytical measurements of antimony and selenium /

Chari, Sangeetha. January 2008 (has links)
Thesis (M.S.)--Youngstown State University, 2008. / Includes bibliographical references (leaves 74-79). Also available via the World Wide Web in PDF format.
85

Speciation dynamics in the freshwater environment : unifying concepts in metal speciation and bioavailability /

Murimboh, John David, January 1900 (has links)
Thesis (Ph. D.)--Carleton University, 2002. / Includes bibliographical references. Also available in electronic format on the Internet.
86

The concentration of selected trace metals in South African soils /

Herselman, J. E. January 2007 (has links)
Thesis (PhDAgric)--University of Stellenbosch, 2007. / Bibliography. Also available via the Internet.
87

Trace analysis by crystal sorption detector and recovery of dental waste

Lee, Chau-wing. January 1981 (has links)
Thesis (M.Phil.)--University of Hong Kong, 1981. / Also available in print.
88

Biomonitoring and assessment of atmospheric trace elements in Portugal methods, response modelling and nuclear analytical techniques /

Reis, Miguel Adrião Mateus dos. January 1900 (has links)
Thesis (doctoral)--Technische Universiteit Delft, 2001. / Includes bibliographical references (p. 139-150).
89

Mass balance determination for trace elements at coal-, peat- and bark-fired power plants /

Tolvanen, Merja. January 2004 (has links) (PDF)
Thesis (doctoral)--University of Helsinki, 2004. / Includes bibliographical references (p. 133-139). Also available on the World Wide Web.
90

Trace elements in the sediments of western Lake Superior and the Duluth-Superior Harbor

Koons, Robert Dey, January 1976 (has links)
Thesis (M.S.)--University of Wisconsin--Madison. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 190-198).

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