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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

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.
2

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.
3

Trace elements determination in Syrian phosphate rocks

Al-Merey, Rafaat January 1989 (has links)
No description available.
4

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
5

Isotopic exchange and complexation of iron, zinc, and manganese in a long-term marine phytoplankton culture

Riedel, Gerhardt Frederick 03 August 1977 (has links)
Graduation date: 1978
6

Topics in the behaviour of atmospheric trace gases /

Khalil, Mohammad Aslam Khan. January 1979 (has links)
Thesis (Ph. D.)--Oregon Graduate Center, 1979.
7

Clinical application of trace analysis of carbon monoxide in expired air /

Wong, Kung-hin. January 1986 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1987.
8

Analysis of trace metals in palm oil.

Fung, Ying-sing, January 1977 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1977.
9

Trace element incorporation in modern speleothem calcite and implications for paleoclimate reconstruction

Hatch, Rosemary 02 February 2015 (has links)
Trace element compositions, expressed as ratios relative to Ca (Mg/Ca, Sr/Ca and Ba/Ca), in drip water and modern speleothem calcite were measured at multiple sites within a single cave system (Natural Bridge Caverns) in central Texas. These measurements are used to investigate how water and calcite compositions respond to changes in climate. Drip water trace element ratios respond to changes in climate and in soil, vadose zone and/or in-cave processes, which are in turn influenced by climate. It is commonly assumed that speleothem calcite directly reflects these changes in the drip water composition. To test this assumption, this study quantifies the partitioning of trace elements into speleothem calcite in a natural cave setting. To determine the controls on calcite trace element ratios, empirical partition coefficients (K [subscript D]) for Mg, Sr, and Ba are measured using a unique time series of water and modern calcite geochemistry at two drip sites. One drip site, dominantly supplied by conduit flow, has relatively invariant calcite trace element compositions that reflect correspondingly small variations in drip water chemistry. A second drip site, supplied by a combination of conduit and diffuse flow, exhibits a seasonal change in drip water composition due to changes in cave-air CO₂ concentrations. The drip water seasonality at this site is recorded in the calcite trace element compositions; however the partitioning of Mg/Ca from drip water to calcite is not controlled by the same mechanism(s) that control Sr/Ca and Ba/Ca partitioning. Results of this study indicate that the partitioning of Mg changes with drip water Mg concentration, temperature and location of the calcite relative to the point of drip impact. Calcite Sr/Ca and Ba/Ca ratios are more strongly influenced by changes in cave-air CO₂ that cause changes in CO₂ degassing, affecting calcite precipitation. This element specific partitioning complicates the interpretation of speleothem trace element records, since calcite Mg/Ca and Sr/Ca may not always covary even at drip sites that experience PCP. Although there is a strong correlation between Mg/Ca and Sr/Ca ratios in the drip water at these sites, there is considerable scatter between these two values in calcite. Average K [subscript D] values at both sites fall within the range of previous theoretical and empirical studies and are 0.025, 0.12 and 0.15 for Mg, Sr and Ba respectively. It is important to note that not all trace element partitioning is controlled by the same mechanism, since this has implications for interpretations of hydrologic processes from speleothems. / text
10

Analysis of Trace Elements in South African Clinkers using Latent Variable Model and Clustering

Abonyi, J, Tamás, FD, Potgieter, S, Potgieter, H 19 March 2003 (has links)
The trace element content of clinkers (and possibly of cements) can be used to identify the manufacturing factory. The Mg, Sr, Ba, Mn, Ti, Zr, Zn and V content of clinkers give detailed information for the determination of the origin of clinkers produced in different factories. However, for the analysis of such complex data there is a need for algorithmic tools for the visualization and clustering of the samples. This paper proposes a new approach for this purpose. The analytical data are transformed into a twodimensional latent space by factor analysis (probabilistic principal component analysis) and dendograms are constructed for cluster formation. The classification of South African clinkers is used as an illustrative example for the approach.

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