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Application of x-ray emission spectrometry to some environmental problems in Africa

Posted on:1994-06-28Degree:Ph.DType:Dissertation
University:Universitaire Instelling Antwerpen (Belgium)Candidate:Eltayeb, Mohamed Ahmed HassanFull Text:PDF
GTID:1471390014992342Subject:Chemistry
Abstract/Summary:
In this work we studied trace element concentrations in four types of environmental samples. In the first part two types of applications of hair trace element analysis were studied: hair as a monitor for environmental exposure to heavy elements and age-related variations in hair trace element content. Analysis of hair from a population group which is thought to stand high risk of contamination by lead from the work environment and to a control group which comprised university students of similar age as the members of the first group was performed. All the members of the exposed group could be differentiated by the high hair lead content. To elucidate the effect of age on hair trace element content, three groups of different age were studied. The first group showed a significantly higher hair trace element content as compared to the other two groups.; In the second part we implemented two types of emission techniques, EDXRF and PIXE, for the analysis of aerosol samples collected at Khartoum, Sudan. High concentrations for the crustal elements were observed in Khartoum aerosol, and relatively low concentrations for the elements which result from anthropogenic activities.; Single particle analysis for the samples collected on Nuclepore showed that most of the particles were soil dust particles.; In the third study, we examined the relationship between mineral aerosol and the soil from which the aerosol is generated and the utility of the currently used reference materials and reference elements for enrichment factors calculation. In this study, the elemental concentration and enrichment factors calculated relative to a specific reference material or reference element showed remarkable similarity in both Sahara and Namib soil and mineral aerosol. In the two types of soils, all the elements, except Si, showed positive fractionation with decrease in the particle size. The concentration for the elements Al, Si, K, Rb and Sr increased slightly with decrease in the particle size, while the concentration for the elements Ti, Mn, Fe, Y and Zr increased by more than a factor of two when the particle size decreased.; In the last part of this study, we developed, optimized and applied a preconcentration technique for the elemental analysis of environmental waters by EDXRF. In this study preconcentration of trace elements in environmental waters on Al(OH){dollar}sb3{dollar} carrier was studied. (Abstract shortened by UMI.)...
Keywords/Search Tags:Environmental, Trace element, Studied, Two types, Concentration
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