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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

Determination of metal concentrations in vegetation, soil, dust, and water in the vicinity of a cement factory in North West province, South Africa / M.H Huyser

Huyser, M H January 2012 (has links)
On a per capita basis, cement is the second most widely consumed product in the world and its demand is increasing globally due to population growth and urbanisation. Manufacturing plants produce cement kiln dust (CKD) as one of the by-products while coal provides the dominant energy source in the manufacturing process. Various meta ls are found in CKD and some of these are micro nutrients with potentially toxic effects. If these are present in large quantities, they pose a direct threat to vegetation, animals and humans. The aim o f this 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 collected. In addition, similar samples (except for water) were taken from a control site situated 72 kilometres in a north-western direction from the factory. The water control sample was collected from the Ditsobotla municipal water supply. Soil. plant and dust samples as well as the sediment from the water sample were acid digested to obtain total metal concentrations . The acid digested samples were analyzed for selected metal concentrations using the ICP-MS. The relationship between soil metal concentrations and particle size distribution as well as the relationship between dust concentrations and Ca concentrations was established to determine the link with the presence on a CMP in the area. The control samples, reference standards and results from similar research performed were used to compare with metal concentrations found in this study. The study revealed that Ni and Cu concentrations are higher in the silt fraction of the soil whilst V, Co, Zn and Pb in the silt fraction are only marginally higher than the complete soil sample. Only Cr and Mn concentrations were higher in soil samples than the control and reference values, while metal concentrations for Cr, Cu, Pb and Mn were higher in the dust samples than the control and the Emission Limit Value (EL V). Moreover, metal concentrations in the vegetation samples are not a concern as the concentrations a re lower than reference values. Cadmium and As levels are of no concern in this study area especially since dust samples had undetectably low levels. The condition of the environment m relation to pollution from the cement factory was established. Although some metals revealed lower concentrations, the study demonstrated the potential of metal contamination particularly Ni, Mn and Cr to the environment vis-a vis on the surrounding vegetation, animals and possibly on humans. It was therefore recommended that ELV limits for South Africa should be established and monitored for cement factories in South Africa coupled with sustainable land management policies. / Thesis (M.Sc.(Environmental Science) North-West University, Mafikeng Campus, 2012
2

Kinetics of the reaction of carbon dioxide/carbon monoxide gas mixtures with iron oxides and the role of the pseudo phases of wustite

Worral, Elizabeth. Coley, Ken January 2005 (has links)
Thesis (Ph.D.)--McMaster University, 2006. / Supervisor: K. S. Coley Includes bibliographical references (leaves 200-209).
3

Development of computer aided heat treatment planning system (CAHTPS)

Vader, Ranjeet D. January 2002 (has links)
Thesis (M.S.)--Worcester Polytechnic Institute. / Keywords: Heat treatment planning system. Includes bibliographical references (p. 129-130).
4

A conic-section simulation analysis of two-dimensional fracture problems using finite element method.

Lau, Kwok-jing. January 1975 (has links)
Thesis (Ph. D.)--University of Hong Kong, 1976. / Typescript.
5

Experimental testing of a computer aided heat treatment planning system

Vaidya, Rohit Subhash. January 2003 (has links)
Thesis (M.S.)--Worcester Polytechnic Institute. / Keywords: heat treatment. Includes bibliographical references.
6

Development in the spectrochemical analysis of metals, alloys, and related metallurgical products /

Nobbs, Jack McKay. January 1900 (has links) (PDF)
Thesis (M.Sc.) University of Adelaide, 1950. / Typewritten copy.
7

The factors influencing the price of metals on the metal market

Walsh, Thomas Patrick F. January 1920 (has links) (PDF)
Thesis (M.S.)--University of Missouri, School of Mines and Metallurgy, 1920. / Thomas P. Walsh determined to be Thomas Patrick F. Walsh from "1874-1999 MSM-UMR Alumni Directory". The entire thesis text is included in file. Typescript. Illustrated by author. Title from title screen of thesis/dissertation PDF file (viewed May 11, 2009)
8

Design, fabrication, and calibration of an instrumented drop weight impact tester /

Dempsey, Craig Thomas, January 1994 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references (leaves 144-147). Also available via the Internet.
9

Effect of mechanical properties on erosion resistance of ductile materials /

Levin, Boris F., January 1998 (has links)
Thesis (Ph. D.)--Lehigh University, 1998. / Includes vita. Includes bibliographical references (leaves 128-132).
10

A conic-section simulation analysis of two-dimensional fracture problems using finite element method

Lau, Kwok-jing. January 1975 (has links)
Thesis (Ph.D.)--University of Hong Kong, 1976. / Also available in print.

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