The newest geochemical and sedimentological studies of the Libkovice Member in the Most Basin revealed existence of a sedimentary cyclicity that is controlled by the change of Earth's orbital parameters and the shape of its orbit. The main objective of this study is to verify the hypothesis whether there is also a similar cyclical record in strata underlying the Libkovice Member. This interval located in top of the Holešice Member consists of lacustrine sediments of a smaller extent represented by the so-called Břešťany Clays. The aim of the diploma thesis was a geochemical analysis of the concentration of selected elements measured by a mobile XRF device from the drilling cores in the stratigraphic interval between the roof of the Main Coal and the base of the Libkovice Member. Also made was a litological description of boreholes and sedimentary texture of selected clay samples. A mineralogical analysis was performed using the X-ray diffraction method. Usefulness of the XRF mobile device was proven especially for the heavier elements (e.g., Fe and Sr) and less for the lighter elements K and Ti. Nevertheless, it was possible to assign the analysed sediments to the already published chemostratigraphic subdivision of the Most Basin and to confirm its validity. The Břešťany Clays horizon was identified...

M.Sc. / The South African wine industry is well respected internationally for producing high quality wines. The possible adulteration of these wines can lead to loss of reputation and a loss of sales and could also be dangerous to consumer’s health. Multi-element analysis of wines is one way of implementing quality control and the same multi-element data can also be used to prove the point of origin. The metal content of the fruit (grapes) should represent the metal content of the soil in which the plants (vineyards) were grown. An Inductively Coupled Plasma Mass Spectrometer (ICP-MS) was used with correct internal standard and interference correction to obtain reliable concentrations for 27 elements (Li, B, Al, Sc, V, Cr, Mn, Co, Ni, Cu, Zn, Se, Rb, Sr, Zr, Nb, Mo, Cd, Sn, Sb, Ba, Ce, Nd, W, Tl, Pb and U) of 1:1 diluted wines and microwave digested vineyard soil from four South-African wine-producing regions: Stellenbosch, Swartland, Robertson and Walker Bay. This multi-element data was then interpreted using multivariate statistical analysis in order to determine which elements have the ability to discriminate between the four regions. Li, B, Sc, Ni, Mn, Co, Cu, and Rb were the elements that were identified to have discrimination ability. 96% of wines and 100% of vineyard soils were correctly classified. Indirectly it has been proven that the metal content of the soil can be correlated to the metal content of the wine. This methodology can be reliably used in industry for quality control and routine provenance determination

[pt] A presente dissertação é uma continuação de pesquisas desenvolvidas por Leite (2006) visando à análise multielementar de rochas (basaltos, obsidianas e folhelhos) por espectrometria de massa com plasma indutivamente acoplado (ICPMS), em combinação com ablação a laser (LA) e utilizando-se vidro borato como alvo de análise. Como no trabalho anterior, os experimentos foram realizados com um sistema LSX-100 (CETAC) acoplado ao espectrômetro Elan 6000 ICPMS (PerkinElmer-Sciex). Como gases carreadores na câmara de ablação foram testados gases puros (Ar, He) e misturas (Ar-He, Ar-N2). Também foram avaliados parâmetros operacionais do laser, tais como: energia de saída, focalização, velocidade de varredura e freqüência de disparo. As novas condições analíticas foram testadas com os padrões preparados por Leite (2006), calculandose os limites de detecção, a exatidão e precisão. Os limites de detecção para 40 elementos (Na, Al, Si, P, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni, Zn, Ga, Rb, Sr, Y, Zr, Nb, Sb, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Ta, Th, U) ficaram compreendidos entre 0,004 mg kg-1 (Tb) e 850 mg kg-1 (Si). Exatidões foram estimadas a partir de análises de materiais de referência certificados (USGS BIR-1, BHVO-2, SCo-1), obtendo-se erros < 10% para Sc, V, Co, Ni, Zn, Rb, Y, Ba, La, Pr, Nd, Tb, Lu e Th e entre 10-20% Na, Al, Si, P, K, Ca, Mn, Fe, Ga, Sr, Y, Zr, Nb, Ce, Sm, Eu, Gd, Dy, Er, Yb, Lu, Hf e U. Precisões, calculadas a partir dos desvios-padrão residuais das curvas de calibração, ficaram em média em 6%, sendo de no máximo 10% para 30 elementos (Na, Al, Si, P, Ca, Sc, V, Cr, Mn, Fe, Co, Zn, Ga, Sr, Y, Zr, Sb, La, Ce, Pr, Eu, Gd, Tb, Dy, Er, Tm, Yb, Lu, Hf e Ta). Foram preparados novos padrões de calibração a partir de dois materiais de referência certificados, o basalto USGS BCR-2 e o folhelho USGS SGR-1. Os novos padrões foram validados utilizando os padrões preparados por Leite (2006) e através de análises independentes. Os coeficientes de determinação (R2) para 24 elementos (Na, Mg, Al, K, Sc, V, Cr, Mn, Fe, Co, Ga, Rb, Sr, Y, Nb, Ce, Nd, Eu, Ho, Yb, Lu, Ta, Pb, U) foram maiores que 0,98 e para os outros 16 elementos, no mínimo, maiores que 0,95 (Si, P, Ca, Zn, Zr, Ba, La, Pr, Sm, Gd, Tb, Dy, Er, Tm, Hf, Th). As metodologias foram utilizadas na caracterização multielementar de amostras de folhelhos, de grande interesse geológico na área de petróleo, e os resultados preliminares são apresentados e discutidos. / [en] The present master dissertation is a continuation of a research study developed by Leite (2006) aiming at the multielemental analysis of rock samples (basalts, obsidians and shale) by inductively coupled plasma mass spectrometry (ICPMS), in combination with laser ablation (LA) and using borate glass as analytical targets. As in the former work, the experiments were performed with a LSX-100 (CETAC) system coupled to an Elan 6000 ICPMS (PerkinElmer-Sciex). Pure gases (Ar, He) and mixtures (Ar-He, Ar-N2) were tested as carrier gas for transporting the aerosol from the ablation cell to the plasma. Different operational parameters of the laser, such as energy, focus, scanning speed and laser frequency were also studied. The new and optimized analytical conditions were tested with the calibration standards prepared by Leite (2006), and limits of detection (LOD), accuracies and precisions (RSD) were estimated. For 40 elements (Na, Al, Si, P, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni, Zn, Ga, Rb, Sr, Y, Zr, Nb, Sb, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Ta, Th, U), the LODs were in the range of 0,004 mg kg-1 (Tb) and 850 mg kg-1 (Si). Accuracies, estimated from the analysis of certified reference materials (USGS BIR-1, BHVO-2, SCo-1), were better 10% for Sc, V, Co, Ni, Zn, Rb, Y, Ba, La, Pr, Nd, Tb, Lu, and Th, and between 10 to 20% for Na, Al, Si, P, K, Ca, Mn, Fe, Ga, Sr, Y, Zr, Nb, Ce, Sm, Eu, Gd, Dy, Er, Yb, Lu, Hf, and U. Analytical precisions, calculated from the residual standard deviations of calibration curves were typically 6%, and at most 10% for 30 elements (Na, Al, Si, P, Ca, Sc, V, Cr, Mn, Fe, Co, Zn, Ga, Sr, Y, Zr, Sb, La, Ce, Pr, Eu, Gd, Tb, Dy, Er, Tm, Yb, Lu, Hf, Ta). New targets were prepared from two certified reference materials: (USGS BCR-2 (basalt) and USGS SGR-1 (shale). These new calibration standards were validated against those prepared by Leite (2006) and also by an independent technique. Coefficients of determination (R2) for 24 elements (Na, Mg, Al, K, Sc, V, Cr, Mn, Fe, Co, Ga, Rb, Sr, Y, Nb, Ce, Nd, Eu, Ho, Yb, Lu, Ta, Pb, U) were better than 0.98, and for further 16 elements better than 0.95 (Si, P, Ca, Zn, Zr, Ba, La, Pr, Sm, Gd, Tb, Dy, Er, Tm, Hf, Th). The method was then used for the multielement characterization of marine shale samples, which are of great geological interest in petroleum research, and preliminary results are presented and discussed.

Ces travaux de thèse apportent de nouvelles contraintes sur la concentration et le comportement de l’H dans le manteau lithosphérique et reposent sur l’étude pétro-géochimique de trois séries de xénolites de péridotites à spinelle, associant les concentrations en élément majeurs et en traces y compris l’H dans les minéraux dits anhydres (les NAMs, ici, olivine, pyroxènes) et hydratés (amphibole). Les effets de la remontée des xénolites dans du magma hôte sur les concentrations en H des NAMs ont pu être étudiés sur une série de xénolites de péridotite du champ volcanique d’Eifel (Allemagne). Une variation intra cristalline de concentration en H peut être identifiée dans l’olivine et non dans les pyroxènes coexistant. Ces profils de concentration en H peuvent être utilisés pour estimer des vitesses de remontées des magmas. Dans le cas des volcans étudiés, ces vitesses sont estimées entre 3.5 et 12 m.s-1. Ces résultats suggèrent que les pyroxènes sont de meilleurs proxy que l’olivine pour quantifier la concentration mantellique de l’H. Les xénolites de Ray Pic (Massif Central, France) ont permis de discuter dans un contexte de point chaud, l’effet de la fusion partielle et du métasomatisme à grande échelle sur les concentrations en H des NAMs. Les concentrations en H des minéraux ne suggèrent pas de lien avec le métasomatisme subit, qu’il soit modal, cryptique, à rapport liquide/roche élevé ou faible. Cependant, en comparant les concentrations en H avec un marqueur de la fusion partielle (Yb du cpx), l’H semble avoir un comportement similaire à une MREE (e.g., Sm ; D(cpx/liquide)~0.29). Enfin, des xénolites composites associant une péridotite accolée à un agent métasomatique ont permis de cibler l’influence du métasomatisme de petite échelle (pluri-centimétrique). L’interaction magma roche identifiée sur une harzburgite en contact avec du basalte montre dans les cas des olivines, des variations chimiques couplé entre éléments majeurs en fonction de leur proximité au filon et les concentrations en H. Plus l’olivine se rééquilibre avec le liquide moins elle contient d’H. Parallèlement dans cette étude, trois échantillons présentent une lherzolite en contact avec une pyroxénite avec 14% d’amphibole, une clinopyroxénite avec 40 % d’amphibole et une amphibolite (98% d’amphibole). Cette contiguïté avec un filon métasomatique permet l’étude du comportement de l’H en contexte de percolation en bordure de filon. Chaque échantillon présente des concentrations en H homogènes pour chacune des phases minérales. Cependant plus les filons contiennent d’amphibole moins il y a d’H dans les NAMs. D’autre part, une nouvelle fois, la corrélation positive entre les concentrations en H des NAMs et le Sm(cpx) en tant que marqueur de métasomatisme suggère que l’H se comporte comme une MREE.En conclusion, les minéraux des spl-harzburgites contiennent en moyenne un peu plus d’H que ceux des spl-lherzolites. Les concentrations en H des olivines sont sensibles à la dévolatilisation lors de la remontée dans le système magmatique et le rééquilibrage avec le magma. Au contraire, les concentrations en H des pyroxènes, spécialement l’opx, sont très homogènes suggérant des concentrations mantelliques. Le comportement de l’H lors de la fusion partielle et du métasomatisme reste complexe ; nos données suggèrent que l’H suit les MREE tel que le Sm. / This thesis provides new constrains on H concentrations and H behaviour in the lithospheric mantle and is based on a petro-geochemical study on 3 spinel-peridotite xenoliths series with major and traces elements analyses, including H in nominally anhydrous minerals (NAMs, olivine and pyroxenes) as well as hydrous minerals (amphibole).Ascent effects through a magmatic system on H concentration of NAMs are studied for a xenoliths series from the Eifel volcanic field (Germany). Intracrystalline variation in H concentration are observe in olivine but not in the coexisting pyroxenes. Such H concentration profiles are used to calculate the rate of magma ascent. For the studied volcanoes, the calculated rate of magma ascent is between 3.5 and 12 m.s-1. Such H concentration variations imply a devolatilisation affecting only olivine, whereas the pyroxenes are homogeneous and then can be used as a better proxy for mantle H concentrations.Ray Pic xenoliths (French Massif Central) belongs to a mantle plume setting, implying the possibility to assess the effect of partial melting and large scale metasomatism on H concentration of NAMs. The H concentrations determined do not suggest a strong link with the suffered metasomatism whether modal, cryptic, at low or high melt rock ratio. However, using H concentrations and a marker of the partial melting (Yb in cpx), H seems to behave as a MREE (e.g., Sm, D(cpx/melt) ~ 0.29).Finally, the composite xenoliths with a peridotite adjacent to a metasomatic agent allow to target the influence of small scale metasomatism (pluri-centimetric). A magma-rock interaction between a harzburgite and a basaltic patch shows that, for olivines, chemical variations in major element as a function of olivine proximity to the vein, is coupled to H concentrations of NAMs. More the olivines are close to equilibrium with the basalt, more the H concentrations are low. Alongside in this study, three samples consist of a lherzolite adjacent a pyroxenite (14% amphibole), to a clinopyroxenite (40% amphibole) and to an amphibolite (98% amphibole) respectively. This special relationship with a metasomatic vein allows to study the behaviour of H during wall rock percolation. Each sample display homogeneous H concentration within each NAMs. However, H concentration is inversely correlated to modal content in amphiboles in the peridotite. Furthermore, a positive correlation between H in NAMs and Sm(cpx) here as a marker of metasomatism suggests, again, that H behaves as a MREE.To conclude, minerals from harzburgite contain in average a bit more H than the one in lherzolite. The H concentration in olivine are sensitive to degassing during magma ascent toward the surface and reequilibrium with magma. On the contrary, H concentration in pyroxenes, especially opx, are very homogeneous suggesting mantle concentration. The behaviour of H during partial melting and metasomatism is complex. However, our data suggest that H broadly follows MREE.

Fifty fragments of young, fresh basalts from the Explorer Ridge, Paul Revere Ridge (Fracture Zone), Dellwood Knolls, and the J. Tuzo Wilson Knolls have been analysed for 12 major and minor elements, as well as 11 trace elements, by X-ray fluorescence spectrometry. Rare earth element concentrations in 25 of the samples have been determined by instrumental neutron activation, and Sr⁸⁷/Sr⁸⁶ ratios have been obtained for 11 of the basalts. The Explorer Ridge basalts have major element compositions similar to most mid-ocean ridge basalts (MORB), and can be classified as ferrobasalts, similar to those of the southern Juan de Fuca Ridge. The incompatible minor and trace elements K, Ti, Rb, Zr, and Nb are weakly to strongly enriched in the Explorer samples, with respect to MORB, part of which is the result of crystal fractionation. The observed trace element and light rare earth element (LREE) enrichment of many of the samples, particularly those from Explorer Deep, suggest that a weak hotspot may exist beneath the Explorer Deep. The adjacent ridge segments, Explorer Rift and the Southern Explorer Ridge, are erupting basalts both enriched and depleted in incompatible elements, which could be an indicator of a chemically heterogenous mantle source, or may be the result of intermittent injection of enriched magmas from the postulated hotspot beneath Explorer Deep into areas producing normal MORB. The enriched basalts do not have significantly different Sr⁸⁷/Sr⁸⁶ ratios from the depleted basalts. All the samples fall within the range of values typical for Juan de Fuca and Gorda Ridge basalts, and East Pacific Rise tholeiites in general. Thus, although the source areas for the 2 basalt types may differ chemically, they are similar radiogenically, unlike-other hypothetically plume-influenced areas such as the Mid-Atlantic Ridge at 45°N and the FAMOUS area. The basalts from the northwest and southeast Dellwood Knolls appear to be related by crystal fractionation, based on major element analysis. However, the very different REE patterns and Sr⁸⁷/Sr⁸⁶ ratios exhibited by the two knolls suggest that they have different mantle sources, one typically depleted (northwest knoll) and one chemically and radiogenically enriched (southeast knoll). In terms of their major and trace element chemistry, the J. Tuzo Wilson Knolls basalts are typical of late-stage volcanism on ocean islands associated with mantle plumes. The hawaiites strongly resemble alkali basalts dredged from several seamounts in the Pratt-Welker Chain, which are co-latitudinal with the J. Tuzo Wilson Knolls on a small circle about the Pacific-Hotspot pole of rotation. Geochronological evidence questions the hypothesis that the mantle plume responsible for Pratt-Welker volcanism is also the source for the J. Tuzo Wilson basalts. The existence of a second mantle plume, 300 km southeast of the first, would explain minor chemical and physiographical differences between the Knolls and the other Pratt-Welker seamounts, as well as the evidence for two phases of volcanism on the southeastern seamounts of the chain. A second plume also explains the coeval volcanism of Bowie Seamount and the J. Tuzo Wilson Knolls. Recent geophysical evidence suggests that the J. Tuzo Wilson Knolls are also part of the Explorer-Dellwood spreading system. Although the JTW basalts are plume-type basalts chemically, the situation appears to be somewhat analagous to other ridge segments where plumes are coincident with the ridge itself. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate

Seamounts play an important role in facilitating the exchange of elements between the oceanic lithosphere and the overlying seawater. This water-rock interaction is caused by circulating seawater and controls the chemical exchange in submarine and sub-seafloor rocks. The exchange mechanism plays a major role in determining the final composition of these submarine rocks. This investigation is designed to evaluate the (i) degree of alteration and element mobility, (ii) to identify relations between alteration types and (iii) to characterise the chemical processes that takes place during seafloor and sub-seafloor alteration in the Central Atlantic region. The investigated submarine rocks are typically altered. They are composed mostly of calcite and clay minerals in addition to original magmatic feldspar, olivine, pyroxene, quartz, biotite, and amphibole.  Elemental analyses show that submarine rocks with high water-rock ratio have experienced near complete loss of Silica and alkali elements to seawater but are enriched in calcium and phosphorous. In addition, there is a strong enrichment of trace elements such as Sr, Ti, Rb and trivalent REEs in altered submarine samples that are likely residual in character. Oxygen and hydrogen isotopic values indicate a low temperature alteration process at less than 50℃.  Nannofossils were present in one sample and investigation suggests that the seamount south of El Hierro evolved from a young Canary activity rather than the early Cretaceous magmatic events as has been argued previously. / Djuphavsberg spelar en viktig roll för att underlätta utbytet av element mellan den oceaniska litosfären och det överliggande havsvattnet. Interaktionen mellan vattnet och bergarterna orsakas av cirkulerande havsvatten och kontrollerar det kemiska utbytet i undervattensbergarterna och som även spelar en viktig roll för att bestämma de slutliga produkterna i dessa bergarter. Undersökningen syftar till att (i) utvärdera graden av kemisk omvandling och rörlighet av elementen, (ii) identifiera samband mellan olika omvandlingstyper och (iii) att karakterisera de kemiska processer som äger rum vid kemisk omvandling av bergarter vid och under havsbottnen i Centralatlanten. De undersökta undervattensbergarterna är generellt kemiskt omvandlade och består av kalcit och lermineral utöver ursprungligt magmatiskt fältspat, olivin, pyroxen, kvarts, biotit och amfibol. Elementanalyser visar att de undervattensbergarter med en hög vatten-berg kvot har förlorat i stort sett all Si och nästan alla alkaliska element till havsvattnet medan en anrikning har skett av kalcium och fosfor. Dessutom har det i de omvandlade undervattensproverna skett en tydlig anrikning av spårämnena Sr, Ti, Rb och av trivalenta sällsynta jordartsmetaller. Syre- och väteisotopvärden indikerar en omvandlingsprocess vid låga temperaturer mindre än 50 °C. I ett prov fanns nannofossiler och en undersökning av dessa tyder på att djuphavsberget söder om El Hierro bildades under en yngre vulkanisk aktivitet än den magmatiska aktivitet som tidigare föreslagits som ägde rum under perioden Krita.

O consumo de peixes e frutos do mar está associado à manutenção de uma dieta saudável em função da sua proteína de elevado valor biológico, da presença de ácidos graxos poli-insaturados e de importantes nutrientes como selênio, ferro, cálcio e fósforo. No entanto, esses organismos representam uma importante fonte de elementos-traço contaminantes para os seres humanos em função da bioacumulação desses elementos que também podem biomagnificar ao longo da cadeia alimentar. Apesar da ocorrência natural de elementos-traço no meio ambiente, sua concentração nos ecossistemas costeiros tem aumentado drasticamente em função de atividades antropogênicas, fazendo com que os organismos marinhos atuem como um elo da contaminação ambiental à contaminação humana. O presente trabalho avalia a concentração de elementos-traço em diferentes tecidos de organismos marinhos sob dois aspectos: (1) o risco alimentar associado ao consumo das espécies analisadas e (2) a bioacumulação dos elementos em diferentes tecidos. Para isso foram analisadas três espécies de peixes comercializadas na cidade de Santos (SP): Sphyraena guachancho (bicuda), Priacanthus arenatus (olho de cão) e Genidens genidens (bagre) e três espécies coletadas em diferentes pontos do Sistema Estuarino de Santos (SP): Callinectes danae (siri azul), Mytella guyanensis (mexilhão) e Mugil curema (parati). O hábito alimentar foi o principal critério para seleção das espécies. O risco alimentar, calculado pelo Índice Provisório de Risco (PHI) e pelo Índice Provisório de Risco Total (PTHI), apresentou valores elevados para Sphyraena guachancho (espécie piscívora) e para peixes e siris coletados no Sistema Estuarino de Santos. A bioacumulação foi associada à espécie, tecido e tipo de elemento avaliado. A espécie piscívora apresentou elevada concentração de Ba, Hg e Ag no tecido muscular, indicando a potencial biomagnificação desses elementos ao longo da cadeia alimentar. Genidens genidens, espécie detritívora, apresentou elevada concentração de Ba, Cd e Pb na nadadeira, possivelmente associado às estratégias de detoxificação da espécie, por meio da imobilização desses contaminantes no esporão ósseo. / The consumption of fish and seafood is associated with the maintenance of a healthy diet due to its protein of high biological value, the presence of polyunsaturated fatty acids and important nutrients as selenium, iron, calcium and phosphorus. However, these organisms represent an important source of contaminant trace elements for humans due to the bioaccumulation of these elements in tissues that can also biomagnify along the food chain. Despite the natural occurrence of trace elements in the environment, its concentration in coastal ecosystems has increased dramatically as a result of anthropogenic activities, causing marine organisms to act as a link between environmental and human contamination. The present work evaluates the concentration of trace elements in different tissues of marine organisms under two aspects: (1) the food risk associated with the consumption of the species analyzed and (2) the bioaccumulation of the elements in different tissues. Three species of fish commercialized in the city of Santos (SP) were analyzed: Sphyraena guachancho (bicuda), Priacanthus arenatus (dog eye) and Genidens genidens (catfish) and three species collected at different points of the Santos Estuarine System (SP): Callinectes danae (blue crab), Mytella guyanensis (mussel) and Mugil curema (parati). The eating habit was the main criteria for selection of the species. The food risk, calculated by means of the Provisional Hazard Index (PHI) and the Provisional Total Hazard Index (PTHI), presented high values for the piscivorous species Sphyraena guachancho and for fish and crabs collected in Santos Estuarine System. The bioaccumulation was associated with the species, tissue and type of element evaluated. The piscivorous species had a high concentration of Ba, Hg and Ag in muscle tissue, indicating the potential biomagnification of these elements along the food chain. Genidens genidens, a detivorous species, presented a high concentration of Ba, Cd and Pb in the fin, possibly associated with the detoxification strategies of the species, through the immobilization of these contaminants in the bone spur.

Thesis (M. Sc.(Chemistry)) -- University of Limpopo, 2017. / Great Letaba and Mokolo Rivers are major sources of water for domestic use, agriculture and recreational activities in Limpopo Province, South Africa. These Rivers are predisposed to pollution sources from atmospheric deposition of mine dust, emissions from power stations and burning fuel, return flows from agriculture and municipal wastewater discharges and sewage effluents, which may potentially affect the quality of water and the inhabiting biota. Arsenic (As) is an element of prime concern in aquatic systems exposed to such pollution sources due to its toxicity to humans and aquatic life. The quantification and speciation of As in Mokolo and Great Letaba Rivers is important to assess the current levels and predict future trends in the quality of the two rivers. Speciation of As in water and sediments is crucial since the toxicity depends on its chemical forms. In this study, various analytical approaches were explored to precisely identify and quantify different As species in water and sediment samples collected from Great Letaba and Mokolo Rivers. Sample preparation was carried out with an intensive care to efficiently identify and quantify As species. Identification of each species in the samples was based on matching standard peaks with retention times by simple injection of standards of As species into Hamilton PRP X100 column. The chromatographic separation and determination of As3+, dimethylarsinic acid (DMA), monomethylarsonic acid (MMA) and As5+ in water and sediment samples were achieved by on-line coupling of high performance liquid chromatography (HPLC) to inductively coupled plasma-mass spectrometry (ICP-MS). A novel extraction method for As species in sediments based on 0.3 M (NH4)2HPO4 and 50 mM EDTA showed no species interconversion during extraction. Baseline separation of four As species was achieved in 12 minutes using gradient elution with 10 mM and 60 mM of NH4NO3 at pH 8.7 as mobile phases. The analytical figures of merits and validation of analytical procedures were assessed and adequate performance and percentage recoveries ranging from 81.1 – 102% for water sample and 73.0 – 92.0% for sediments were achieved. The As species concentration in water and sediment samples were found in the range 0.224 – 7.70 μg/L and 74.0 – 92.0 ng/g, respectively. The DMA was not detected in both water and sediment samples. viii The As content in sediments depends on the solid phase partitioning between inorganic As species and trace elements such as iron (Fe), manganese (Mn) and aluminium (Al). Knowledge of the extent of this partitioning is important to evaluate the distribution and pathways of As in water, aquatic organisms and possible exposure of animals and human beings. Therefore, total concentrations of As, Fe, Mn and Al in water and sediment samples were determined using ICP-MS and inductively coupled plasma–optical emission spectrometry (ICP-OES). The analytical procedures were validated using standard reference materials (SRMs) with percentage recoveries of trace elements ranging 84.0 – 95.6% for water samples and 75.0 – 120% for sediments. The As, Fe, Mn and Al concentrations obtained were further assessed for safe drinking water, irrigation water and for sediments quality about standard guidelines. Moreover, As species concentrations correlated with Fe, Mn and Al and the observed interactions depend on the adsorption capacities between As species and these trace elements. The inorganic species in water samples were also determined by employing off-line mode of solid phase extraction (SPE) procedure using multi-walled carbon nanotubes (MWCNTs) impregnated branched polyethyleneimine (BPEI) as an adsorbent material. The MWCNTs-BPEI characterised with X-ray powder diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and Thermogravimetric analysis (TGA) techniques indicated successful modification of the nanomaterial. The MWCNTs-BPEI exhibited selective retention of As5+ in the presence of As3+ in water samples with the achieved pre-concentration factor of 23.3. The retained As5+ was then eluted and detected using ICP-MS. A limit of detection (LOD) of 0.0537 μg/L and limit of quantification (LOQ) of 0.179 μg/L were achieved. The obtained percentage recovery of 81.0% validated the SPE procedure for selective retention of As5+. The As5+ concentrations determined after the SPE procedure were found in the range of 0.204 – 7.52 μg/L, which are in good agreement with As5+ results obtained using HPLC-ICP-MS.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22425号 / 工博第4686号 / 新制||工||1731(附属図書館) / 京都大学大学院工学研究科都市社会工学専攻 / (主査)教授 小池 克明, 教授 立川 康人, 准教授 柏谷 公希 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM

Concentrations of trace minerals within the body are known to impact reproductive processes. Thus, the current study analyzed the effects of using an injectable trace mineral supplement containing selenium, zinc, copper, and manganese during a superovulation protocol on embryo outcomes in donor beef cows and further effects on pregnancy rate in recipient females. We hypothesized that an injectable trace mineral (TM) supplement provided to cows fed to meet known nutrient requirements would increase TM status and influence superovulation, embryo characteristics, and enhance pregnancy rates. Our findings indicate that the injectable TM increased concentration of Se within the liver. However, superovulatory response, embryo production, quality grade, and developmental stage were not influenced by TM status. In addition, embryo treatment did not influence pregnancy rate, gestation length, or calf body weight.