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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.
1

Trace elements (MN, B, Zn, Cu and Mo) their effect on the growth of trees, particularly Pinus resinosa, Robinia pseudoacacia and Alnus glutinosa /

Iyer, Jaya Ganpathi, January 1962 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1962. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 43-51).
2

Bioavailability of cadmium, copper, nickel and zinc in soils treated with biosolids and metal salts : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy at Lincoln University /

Black, Amanda. January 2010 (has links)
Thesis (Ph. D.) -- Lincoln University, 2010. / Main page numbering ends at 206 followed by single page numbered 224. Also available via the World Wide Web.
3

Chromium in San Francisco Bay inorganic speciation, distribution, and geochemical processes /

Abu-Saba, Khalil Elias. January 1994 (has links)
Thesis (M.S.)--University of California, Santa Cruz, 1994. / Typescript. Includes bibliographical references (leaves 159-166).
4

Geochemical aspects of atmospherically transported trace metals over the Georgia bight

Mullins, Ballard Marvin 05 1900 (has links)
No description available.
5

Trace elements determination in cancerous and noncancerous human tissues using instrumental neutron activation analysis

Choi, In Sup 08 1900 (has links)
No description available.
6

Activation analysis of trace elements in serum

Varcoe, Frederick Turner, January 1974 (has links)
Thesis--University of Florida. / Description based on print version record. Typescript. Vita. Bibliography: leaves 185-202.
7

Lead, copper and zinc in deciduous teeth and the diet of schoolchildren in Kamloops and Trail, B.C.

Onishi, Geraldine Mineko January 1980 (has links)
The accumulation of metal contaminants in the human environment has received a great deal of attention during the last several years as it has become apparent that their presence, in excess, represents a threat to human health. Biochemical assays to determine concentrations of metals in the human body have used such tissues as blood, bone, hair, nails and, more recently, teeth. The present study attempts to provide further evidence for the use of deciduous teeth as indicators of human exposure to concentrations of lead, copper and zinc as a result of ore smelting operations in Kamloops and Trail, British Columbia. Kamloops represents an area of minimum exposure to smelter operations in contrast to Trail where a lead/zinc smelter has been operating for many years. Concentrations of lead, copper and zinc in deciduous teeth from geographically-stable Kamloops children, aged 5 years to 12 years, were compared to concentrations found in a similar population of geographically-stable Trail children. Whole teeth were digested in nitric and perchloric acids and trace element concentrations were determined using inductively coupled plasma emission spectroscopy. Mean lead and zinc concentrations for Kamloops and Trail teeth, respectively, were: 31.6 ± 7.33 ppm and 48.2. ± 11.5 ppm for lead (p < 0.05) and 103.4 ± 23.6 ppm and 111.9 ± 15.4 ppm for zinc. Copper was undetectable at < 1 ppm in all teeth. Locally-grown foods from each area and foods grown elsewhere were also analyzed for lead, copper and zinc in an effort to establish the possible contribution of these elements from local food resources in Kamloops and Trail. Twenty-four hour diet composites were collected and analyzed for copper and zinc by atomic absorption spectroscopy. Mean copper and zinc concentrations for foods grown in Kamloops and Trail, respectively, were: 1.5 ± 0.4 ppm and 1.6 ± 0.9 ppm for copper and 3. 2 ± 1.3 ppm and 3.1 ± 0.9 ppm for zinc. Mean copper and zinc concentrations for non-locally grown foods collected from Kamloops and Trail, respectively, were: 1.1 ± 0.2 ppm and 1.6 ± 0.8 ppm for copper and 5.8 ± 1.9 ppm and 6.5 ± 0.3 ppm for zinc. Lead was determined by plasma emission spectroscopy, and was found to be undetectable at < 1 ppm in all food samples. To assess the extent of maximal consumption of locally-grown foods, selected home gardeners in the Brocklehurst district of Kamloops and the Genelle district of Trail were interviewed. Seasonal consumption and home food preservation practices were determined. In addition, 24-hour diet recalls were obtained from 177 Brocklehurst district children in September and April, 1977-78 to determine "typical" eating patterns of these children. . The amount of locally-grown foods consumed was dependent mainly on season of the year; however, choice of food by the children on the whole did not differ from fall to spring. The recalls also indicated that males consumed more food than females, particularly protein. Meals, especially breakfast, were frequently missed, and non-nutritious snacks were common to the diets of many of the children. Results from this study indicated that, although deciduous tooth lead concentrations were significantly (p<0.05) higher in Trail than in Kamloops, samples of locally-grown foods obtained in 1978 from these two communities were not excessively high in lead, zinc or copper. In fact, these elements in foods compared well to concentrations reported in other areas of North America. It would appear, then, that the higher concentrations of lead in Trail teeth are a result of increased intake from other environmental sources. Analyses of food consumption patterns of gardening families revealed that local foods comprised an important part of the diet. Measures should be taken to ensure the continued safety of foods in areas where mineral mining and smelting occur. / Land and Food Systems, Faculty of / Graduate
8

Trace elements determination in Syrian phosphate rocks

Al-Merey, Rafaat January 1989 (has links)
No description available.
9

Solvent technique for trace analysis in oil-base samples.

January 1979 (has links)
by Mok Chuen Shing. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1979. / Includes bibliographies.
10

Applications of [beta]-cyclodextrin epichlorohydrin copolymer in trace analysis.

January 2003 (has links)
Liu Ho Yan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references. / Abstracts in English and Chinese. / Abstract (Chinese) --- p.ii / Abstract --- p.iii / Acknowledgement --- p.iv / List of Tables --- p.v / List of Figures --- p.vi / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Overview and history --- p.1 / Chapter 1.2 --- Structure of β-cyclodextrin --- p.2 / Chapter 1.3 --- Complexation with aromatic compounds --- p.2 / Chapter 1.4 --- Scope of the thesis --- p.6 / Chapter 1.5 --- References --- p.8 / Chapter Chapter 2 --- Synthesis and characterization of β-cyclodextrin epichlorohydrin copolymer --- p.10 / Chapter 2.1 --- Introduction --- p.10 / Chapter 2.2 --- Effects of major parameters on polymerization --- p.11 / Chapter 2.3 --- Polymerization mechanisms --- p.13 / Chapter 2.4 --- Synthesis and characterization of β-cyclodextrin epichlorohydrin copolymer --- p.13 / Chapter 2.5 --- References --- p.18 / Chapter Chapter 3 --- β-Cyclodextrin epichlorohydrin copolymer as a solid-phase extraction sorbent for aromatic compounds --- p.19 / Chapter 3.1 --- Introduction --- p.19 / Chapter 3.2 --- Experimental --- p.22 / Chapter 3.3 --- Results and discussion --- p.25 / Chapter 3.3.1 --- Effect of pH on the extraction of aromatic compounds --- p.25 / Chapter 3.3.2 --- Optimum stirring time for the extraction of aromatic compounds --- p.28 / Chapter 3.3.3 --- Recoveries of aromatic compounds --- p.28 / Chapter 3.3.4 --- Analysis of synthetic standard sample --- p.30 / Chapter 3.4 --- Conclusions --- p.33 / Chapter 3.5 --- References --- p.33 / Chapter Chapter 4 --- Simultaneous determination of Ni(II) and Cu(II) in tea sample by EDXRF after preconcentration with 4-(2-pyridylazo)resorcinol-included β-cyclodextrin epichlorohydrin copolymer --- p.40 / Chapter 4.1 --- Introduction --- p.40 / Chapter 4.2 --- Experimental --- p.41 / Chapter 4.3 --- Results and discussion --- p.45 / Chapter 4.3.1 --- Optimum pH for the inclusion of PAR in β-CDEP cavity --- p.45 / Chapter 4.3.2 --- Saturation time for the inclusion of PAR in β-CDEP cavity --- p.45 / Chapter 4.3.3 --- Optimum pH for the reaction between PAR and metal ions --- p.47 / Chapter 4.3.4 --- Calibration curves and detection limits of Ni(II) and Cu(II) --- p.47 / Chapter 4.3.5 --- Analysis of synthetic standard sample --- p.50 / Chapter 4.3.6 --- Analysis of tea sample --- p.50 / Chapter 4.4 --- Conclusions --- p.53 / Chapter 4.5 --- References --- p.53 / Chapter Chapter 5 --- Conclusions --- p.55

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