Dissertations / Theses: 'Mineral trace elements'

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Peters, James C. "Evaluating the efficacy of dietary organic and inorganic trace minerals in reproducing female pigs on reproductive performance and body mineral composition." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1141661190.

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Tanner, Dominique. "In situ mineral geochemistry as a guide to ore-forming processes." Phd thesis, Canberra, ACT : The Australian National University, 2014. http://hdl.handle.net/1885/125140.

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Isotopic and trace element analyses are essential to our understanding ore-forming processes, but traditionally these techniques have required bulk digestion of rocks and minerals. Recent advances in in situ microanalytical techniques permit us to analyse samples on a mineral-by mineral basis and probe the chemistry of individual growth bands in minerals, providing a near-continuous record in any zoned mineral. This thesis is composed of five studies using the in situ geochemistry of 'gangue' (non-ore) minerals to elucidate cryptic ore-forming processes that are obscured using conventional analyses. The first half of this thesis presents coupled isotopic and trace element analyses in quartz and pyrite from magmatic-hydrothermal Cu-Au deposits. These studies revealed complex chemical zonation, providing a detailed record of cryptic fluid chemistry and depositional processes. A distinct isotopic signature and residual metastable silica hydrates in quartz microcrystals from the El Indio deposit, Chile provided the first evidence for silica maturation in a high-temperature environment and the first evidence for non-equilibrium isotope fractionation in quartz. The second half of this thesis focuses on the trace element chemistry of minerals from the Bellevue Core, a ~3 km drillcore intersecting the upper half of the Bushveld Complex, South Africa - the largest known repository of platinum-group elements (PGEs). These studies revealed a prospective PGE horizon and provide the first evidence for extensive equilibration of plagioclase in cumulate rocks.

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Morrison, Elizabeth. "The contribution of Australian wheat and wheat products essential trace mineral intake." Thesis, Queensland University of Technology, 1996. https://eprints.qut.edu.au/36731/1/36731_Morrison_1996.pdf.

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Nutrition authorities' current recommendations include an increased consumption of whole grain cereal products, including wheat products, in order to increase consumption levels of dietary .fibre. However, the essential trace mineral contribution of such products tends to be underestimated. The trace mineral data for Australian wheat and wheat products, moreover, tends to be lacking or out-of-date. Consequently, a survey was conducted to obtain information on the nutritional value of wheat and wheat products with regard to trace minerals. Wheat grain samples were procured from around Australia, over two seasons in most cases. A method was developed utilising a microwave digestion procedure and inductively-coupled plasma atomic emission spectroscopy (ICP-AES) to analyse these samples for the following minerals (mean result of 233 samples in parenthesis): magnesium (1160mg/kg), zinc (18mg/kg), iron (30mg/kg), manganese (33mg/kg), copper (3.2mg/kg), nickel (0.30mg/kg), chromium (0.04mg/kg), cobalt (0.03mg/kg), cadmium (less than detection limit) and aluminium (3.7mg/kg). Mineral content was, generally, strongly correlated (positively) with protein content. Significant geographical and seasonal variations in the mineral content of wheat grain were identified. A number of wheat products were also analysed as above. An assessment of the contribution of wheat and wheat products to the mineral intake of a general adult Australian population was explored and concluded to be significant.

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Martins, Lucelene. "Geração e migração de magmas graníticos na crosta continental: estudos de detalhe em granitos e migmatitos da região de Nazaré Paulista (SP)." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/44/44135/tde-19042007-155618/.

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As condições de geração e migração de magmas na crosta continental foram investigadas a partir de estudos de detalhe em dois afloramentos de granitos anatéticos tipo Nazaré Paulista (Nappe Socorro Guaxupé, região de Atibaia, SP), utilizando como ferramentas principais a geoquímica de elementos maiores e traços em rochas e minerais e a isotopia Sr-Nd. O granito Nazaré Paulista tem uma ampla variedade composicional, sendo as duas variedades principais um granada leucogranito e um granada-biotita granito cinza com uma rede de vênulas de leucogranito (~625 Ma, U-Pb monazita). Ambos os tipos formam corpos sub-concordantes de dimensões decamétricas nos dois afloramentos; as relações de contato quando observadas indicam a intrusão posterior dos granada leucogranitos. Dois tipos de leucossomas foram reconhecidos em paragnaisses migmatíticos associados aos granitos Nazaré Paulista: (1) granada-biotita tonalito com baixa razão Rb/Sr (0,3), padrões de ETR pouco fracionados ((La/Yb)N = 4-5) e com anomalia negativa de Eu e assinatura isotópica Sr-Nd idêntica à do mesossoma; (2) granada leucogranito, com razão Rb/Sr de ~0,56, padrões de ETR pouco fracionados ((La/Yb)N = 5), com anomalia positiva de Eu e eNd(t) idêntico ao do mesossoma, mas com 87Sr/86Sr(t) mais baixa. Ambos os tipos de leucossomas são distintos dos granitos e foram interpretados como produtos da fusão em presença de água do paragnaisse, respectivamente antes e depois da geração de feldspato potássico no protolito. Alguns contrastes geoquímicos relevantes são observados entre os granitos cinza e os leucogranitos: os primeiros apresentam maior mg# e Zr e padrões de ETR mais fracionados; as razões Rb-Sr de ambos os tipos são semelhantes (0,4-0,7). A assinatura isotópica Sr-Nd dos granitos mostra importante variação (eNd(t) = -16 a -13 e 87Sr/86Sr(t) = 0,716-0,728); apenas duas amostras de leucogranito têm assinatura coincidente com o campo dos paragnaisses regionais. Assumindo os paragnaisses como fonte única dos granitos Nazaré Paulista, é necessário que a fusão tenha ocorrido em desequílibrio e em presença de água. A química de elementos traços em granada foi fundamental para a identificação dos diversos processos de diferenciação que respondem pela variedade de granitos observada. Parte dos granitos cinza carrega um componente restítico, representado por granadas com núcleos ricos em ETRP+Y semelhantes às granadas dos paragnaisses encaixantes. As vênulas de granada leucogranito que cortam o granito cinza são formadas provavelmente pela ?refusão? do mush original durante a rápida ascensão e exibem granadas pobres em ETRP, cujos teores aumentam para a borda, definindo um padrão tipicamente magmático. Os leucogranitos que formam corpos isolados podem em parte corresponder a diferenciados do granito cinza, conforme indicado pelas relações de campo e pela geoquímica de rocha. No entanto os leucogranitos com alta 87Sr/86Sr(t) apresentam granadas com núcleos ricos em ETRP+Y e monazita com composição similar a dos paragnaisses, reforçando a hipótese de serem estes produtos da fusão direta de paragnaisses.
The conditions of melt generation and migration in the continental crust were investigated through a detailed study of two outcrops of the anatectic Nazaré Paulista granites (Socorro-Guaxupé, Nappe, Atibaia region, SE Brazil), using as main tools the rock and mineral major and trace-element geochemistry and Sr-Nd isotopy. The Nazaré Paulista granite shows a wide compositional variation, and can be grouped into two main types: a garnet leucogranite and a veined grey garnet-biotite granite, the latter dated at ~625 Ma (monazite U-Pb ID-TIMS). These types occur as subconcordant bodies 10-50 m wide and are present in both outcrops; where observed, the contact relationships show that the garnet leucogranites intruded after the grey granites. Two types of leucosome were recognized in migmatitic paragneisses associated to the Nazaré Paulista granites: (1) garnet-biotite tonalite with low Rb/Sr (0.3 ), slightly fractionated REE patterns ((La/Yb)N = 4-5) with negative Eu anomalies and Sr-Nd isotope signature identical to that of the mesosome; and (2) garnet leucogranite, with Rb/Sr ~0.56, slightly fractionated REE patterns ((La/Yb)N ~ 5) with positive Eu anomalies, eNd(t) identical to that of the mesosome, but lower 87Sr/86Sr(t). Both leucosomes are different from the granites, and were interpreted as the products of water-present melting of the paragneiss, respectively before and after the crystallization of K-feldspar in the protolith. Some relevant geochemical contrasts are observed between the two types of Nazaré Paulista granites: compared to the leucogranites, the gray granites show greater mg# and Zr and more fractionated REE patterns; the Rb/Sr ratios of both are low (0.4-0.7). The Sr-Nd isotope signature has important variations (eNd(t) = -16 to -13 and 87Sr/86Sr(t) = 0.716-0.728); only two leucogranite samples have signatures that are coincident with the field of the regional paragneisses. Assuming the paragneisses as the only source of the Nazaré Paulista granites would require that melting occurred under disequilibrium and water-present conditions. The trace-element chemistry of garnet was important to identify the differentiation processes that respond for the observed variety of anatectic granites. Part of the gray granites carries a restitic component, represented by ETRP+Y-rich garnet cores that are similar to the garnets from the country-rock paragneisses. The garnet leucogranite veins that cut the gray granite were probably formed by \"partial remelting\" of the original mush during rapid ascent, their idiomorphic garnet crystals have a distinctive composition (low HREE in the cores, increasing slightly to the rims), interpreted as magmatic. Some of the leucogranites forming isolated bodies may have been generated by fractionation from the gray granite, as indicated by field relations and rock geochemistry. On the other hand, the leucogranite with high 87Sr/86Sr(t) has ETRP+Y-rich garnet cores and its monazite is compositionally similar to that of the paragneisses, features indicative that they were probably produced by direct melting of these rocks.

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Hill, David T. "Removal of trace elements from coal using a multiple-property processing circuit." Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-01242009-063125/.

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Marozas, Dianne Catherine. "The effects of mineral reactions on trace metal characteristics of groundwater in desert basins of southern Arizona." Diss., The University of Arizona, 1987. http://hdl.handle.net/10150/191127.

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The geochemistry, of groundwater collected from deep wells in the western section of the lower Santa Cruz basin of southeastern Arizona, was studied in order to determine the extent to which geochemica] analysis can be used to assess fluid flow and major and trace element migration patterns along hydrologic flowpaths in desert basins. Interaction between groundwater and enclosing sediments, and mixing between chemically distinct basin groundwater is found to exert a significant control on the chemical patterns that have evolved in the system. Activity-activity diagrams of the Na-Si-O-H system show that groundwater throughout the basin clusters near the three phase boundary between fluid, kaolinite, and montmorillonite and trends along the boundary to higher log (aNa⁺/aH⁺) values. A reaction model generated with computer program PHREEQE, that combines silicate weathering, kaolinite-Na-beidellite equilibrium, calcite equilibrium, and solution mixing, can simulate trends in groundwater composition along flowpaths in the basin. Trace metals introduced into the basin by the weathering of a buried porphyry copper deposit become spatially separated upon migration. Metal concentrations are found to be correlated to major cation concentrations. Cu is associated with high Na concentrations and a high ratio of Carbonate:Ca, whereas Zn is associated with high Ca concentration and a low ratio of Carbonate:Ca. Behavior of Cu and Zn during low-temperature transport can be controlled by the effects of mineral alteration on groundwater composition. Computer analysis of early basin diagenesis shows that changes in major solute composition that accompany weathering, constrained by equilibrium with clays and calcite, can produce the metal segregation pattern observed in the basin. Because the aquifer is strongly influenced by silicate and carbonate mineral equilibrium, the introduction of Central Arizona Project recharge, which is not in equilibrium with alluvial minerals, into the basin, requires a response by mineral reactions that attempt to restore the system to a state of equilibrium with kaolinite, montmorillonite, and calcite. A reaction model is developed to predict the consequent effects of outside recharge on groundwater quality.

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Nel, Marika Verita. "The influence of coal-associated trace elements on sintering and agglomeration of a model coal mineral mixture / M.V. Nel." Thesis, North-West University, 2009. http://hdl.handle.net/10394/6413.

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A series of experiments was conducted to investigate the potential influence of selected inorganic compounds on sintering and agglomeration of a model mineral mixture. The minerals and inorganic compounds were chosen based on the constituents found in coal. The study simulated ash formation processes in the temperature range of 500 °C to 1000 DC. The mineral mixture consisted of kaolinite, quartz, pyrite, siderite, calcite, Ti02 and magnesite in a fIxed ratio. The mixture was doped with 4% (by weight) of each trace or minor element species. Different analytical methods were employed to investigate the extent of sintering and agglomeration and to identify the possible interactions between the species. Compressive strength measurements, TG/DTA, SEMIEDS and XRD analysis were used to evaluate the interactions in oxidizing and inert atmospheres. The influence of the compounds on the reducing-atmosphere ash fusion temperatures of the mineral mixture was also investigated. The results indicated that NaCl, Na2C03, Ge02, Mn20 3, NbS2, srCo3 and PbS increased sintering in the mineral mixture in the oxidizing atmosphere. Sintering was increased by enhancing sulfation of limestone, and/or by affecting the characteristics of the aluminosilicate phases. Na2C03, Ge02 and Mn20 3 increased sintering of the mineral mixture in the inert atmosphere by affecting the characteristics of the alurninosilicate phases. MOS2 and PbMo04 decreased sintering of the mineral mixture in the oxidizing atmosphere, while CU2S, CuS, PbS and NaCI decreased sintering in the inert atmosphere. The results obtained in oxidizing and inert atmospheres indicated that the oxidation numbers of the cations and the anions associated with the different compounds affected the potential of the additives to influence sintering and agglomeration of the mineral mixture. The influence of the inorganic compounds on the mineral mixture at different ashing temperatures was investigated with the ash fusion temperature test. The results indicated that the ash fusion temperatures were decreased by the addition of GeS and PbC03 at an ashing temperature of 500 °C, decreased by SrC03 at an ashing temperature of 815°C, and increased by cr03 at an ashing temperature of 500°C. The results confirm that the addition of trace element compounds can result in the formation of species with lower melting points, and that the ashing temperature has an influence on the ash fusion temperatures.
Thesis (Ph.D. (Chemistry))--North-West University, Potchefstroom Campus, 2010.

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Ashley, Kyle Thomas. "Constraining Metamorphic and Tectonic Evolution in Convergent Terranes: How Trace Elements and Mineral Inclusions Shape Mechanical and Reconstructive Models." Diss., Virginia Tech, 2015. http://hdl.handle.net/10919/52888.

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Conventional thermobarometry in metamorphic systems has been primarily limited to constraining peak temperature (or pressure) along a generalized P-T loop. This is largely attributed to the assumption that mineral assemblages and chemistries achieve a state closest to equilibrium with the maximum thermal (and therefore energetic) input at these peak conditions. However, this traditional approach is limited in providing much information about the evolution of a metamorphic terrane, which is modified by tectonic (kinematic) forces, fluid and component mobility, and heating duration. The ubiquity of quartz in the continental crust has driven much interest in using the phase for thermobarometric purposes. In this dissertation, I discss the application of elastic theory in reconstructing conditions of inclusion encapsulation through inclusion pressure estimation with Raman spectroscopy. In some instances, overpressuring of quartz inclusions in garnet give evidence for high-pressure formation conditions. When analyses are collected from garnet core to rim, pressure paths along garnet growth can be inferred (if temperature can be reasonably estimated). In high-T, low-P terranes, quartz may become dilated if the inclusion adheres to the host. If a quartz inclusion is sufficiently stretched, transformation to a low-density polymorph may occur. Trace element uptake, particularly Ti, have been characterized in quartz and understood to be the result of a temperature- (and to a lesser extent, pressure-) sensitive substitution for Si4+. However, the application of the Ti-in-quartz thermobarometer in quartz mylonites has led to mixed results due to the low-Ti resetting that occurs with dynamic recrystallization. We applied defect energy simulations and took a global assessment of deformed quartz trace element chemistries to infer that sweeping grain boundaries provide short pathways that allows localized re-equilibration with a Ti-undersaturated medium, resulting in Ti removal from the quartz lattice. In addition, thermodynamic pseudosection modeling has provided a method to assess Ti activity as a dynamic parameter – one that evolves as the phase stability changes through prograde and retrograde metamorphic reactions. With this understanding, better growth-composition models can be derived to infer complex pressure-temperature-time-deformation (P-T-t-D) histories of metamorphic rocks. These techniques and results are coupled with conventional thermobarometry techniques to provide a more comprehensive picture of the conditions experienced by a rock through the evolution, from burial to exhumation to the Earth's surface. The thermal evolution is used to provide conceptual thermal-kinematic models to explain tectonic evolution and heat advection in the continental lithosphere in ancient mountain belts.
Ph. D.

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Will, Sonia Elisabete Alves de Lima. "Avaliação da concentração de elementos traço e respectivos mapas de distribuição em placenta bovina." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/10/10132/tde-28032011-102928/.

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O desenvolvimento sadio e harmonioso de uma gestação está relacionado diretamente a nutrição fetal equilibrada. Alguns minerais são essenciais por meio das funções desempenhadas no metabolismo, manutenção e crescimento fetal. As carências minerais estão entre os fatores que mais contribuem para a baixa produtividade de rebanho, gerando perdas econômicas significativas. Desse modo estudos que auxiliam na compreensão das razões para a baixa produtividade em rebanhos são importantes. A placenta atua como uma barreira seletiva ao fornecimento adequado de nutrientes durante a gestação. O principal objetivo deste estudo foi determinar a concentração de elementos traço para animais não manipulados (GCO) e clonados (GCL) para períodos gestacionais e obter mapas de distribuição qualitativos para placenta de bovinos GCO e GCL. As amostras de tecido placentário foram selecionadas e agrupadas em três períodos gestacionais: estágio 1, 90 dias; estágio 2, 135 dias e estágio 3, 235 dias. Todas as amostras foram analisadas para os elementos constituintes e traço por Espectrometria de Raios X. Os resultados obtidos nas análises de tecido placentário contendo elementos constituintes e traço indicaram que os procedimentos de preparação foram adequados. Os resultados obtidos indicaram variações significativas para os elementos Na, Mg, P, Cl, K e Ca. Os mapas de distribuição elementar confirmaram que a maior concentração elementar ocorreu na região de interdigitação entre as criptas carunculares do epitélio uterino e as vilosidades cotiledonária com células trofoblásticas na região dos placentônios e nas glândulas endometriais da região interplacentomal, indicando que nestas regiões intensificam-se as trocas de nutrientes entre mãe e feto. Para os resultados obtidos na avaliação dainterelação elementar, quanto as amostras de placentônio bovino clonado observou-se as interelações entre Ca-Fe, Cu-Fe, Zn-Ca, Fe-Zn, Ca-Cu e Cu-Zn. Pelo exposto acima, concluiu-se que as análises químicas foram adequadas para a determinação da concentração de elementos constituintes e traço e que a análise qualitativa dos mapas bidimensionais e mapas de correlação obtidos por meio de experimento com radiação Síncrotron foram essenciais para a discussão sobre as alterações nas regiões selecionadas e períodos de gestação avaliados.
The healthy and harmonious development of a gestation is directly associated to a balanced fetus nutrition. Some minerals are essential because of their functions developed in the metabolism, maintenance and fetus development. Mineral deficiencies are among the factors that contribute the most for a low productivity of the cattle, generating significant economic loss. Thus, studies that help understand the reasons for a low productivity in cattle are important. The placenta works as a selective barrier to the adequate supply of nutrients during the gestation. The aim of this study was to determine the concentration of trace elements for non-manipulative animals (GCO) and cloned animals (GCL) for gestational periods and to obtain maps of qualitative distribution for the placenta of bovines GCO and GCL. Samples of placenta tissues were selected and grouped in three gestational periods: stage 1, 90 days; stage 2, 135 days; and stage 3, 235 days. All the samples were analyzed for the constituent elements and traces by X Rays Spectrometry. The results obtained in the analyses of placenta tissue bearing constituent elements and trace indicated that the procedures of preparation were adequate. The results indicated significant variations for the elements Na, Mg, P, Cl, K e Ca. The maps of elementary distribution confirmed that the highest elementary concentration occurred in the region of inter-digitation of carunculate vaults of the uterine epithelium and cotiledonary vilosities with trophoblast cells, in the regions of the placentons and endometrial glands of the interplacentomal region, confirming that, in these regions, nutrient exchanges intensify between mother and fetus. For the results obtained in evaluation of the elementary interrelation in relation to the samples of cloned bovine placentons we observed that the maps demonstrated several interrelations between Ca-Fe, Cu-Fe, Zn-Ca, Fe-Zn, Ca-Cu, and Cu-Zn. By these results, we concluded that the chemical analyses were adequate for the determination of the elementary concentration of constituent elements and trace and also that the qualitative analysis of the bi-dimensional maps and correlated maps obtained through experiments with Synchrotron radiation were essential for the discussion on alterations on selected regions and on evaluated periods of gestations.

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Moura, e. Silva Francisco César de [UNESP]. "Avaliação dos valores séricos e hepáticos de elementos minerais em novilhas nelore, criadas extensivamente, suplementadas com mistura mineral comercial." Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/89296.

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Made available in DSpace on 2014-06-11T19:23:59Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-01-26Bitstream added on 2014-06-13T20:11:42Z : No. of bitstreams: 1 mouraesilva_fc_me_botfmvz.pdf: 536732 bytes, checksum: b483c8eb0344fa45e6c29e1db8477c14 (MD5)
Fundação para o Desenvolvimento da UNESP (FUNDUNESP)
O presente trabalho teve como objetivo determinar os elementos minerais no soro sangüíneo (magnésio, cobre, selênio, zinco, fósforo, cálcio, potássio, ferro) e no tecido hepático (cobalto, cobre, selênio, manganês, molibdênio e zinco) em seis diferentes momentos durante um período de dezesseis meses e verificar se houve variação entre eles. Foram utilizadas 25 novilhas mestiças Nelore, com idade média de 18 meses, que permaneceram durante todo o tempo do experimento no mesmo pasto de Brachiaria brizantha. Os animais ainda receberam mistura mineral comercial em cocho coberto e água à vontade e foram submetidos à coleta de fragmentos hepáticos e sangue para obtenção de soro. Análises da pastagem também foram realizadas nos mesmos momentos em que foram colhidas as amostras de soro e fígado (exceto em fevereiro 2003). A água e o sal mineral também foram analisadas. Os níveis médios dos elementos no tecido hepático foram, respectivamente para as seis diferentes colheitas: Co 0,27;0,27; 0,23;0,21; 0,23 e 0,24 ppm; Mn 9,07; 8,55; 8,67; 8,40; 7,90 e 7,25 ppm; Mo 4,18; 3,85; 3,68; 3,32; 3,54; 3,19 ppm; Zn 113,4; 101,94; 97,91; 92,46; 88,29 e 81,74 ppm; Cu 40,76; 36,33; 24,50; 24,70; 77,75 e 128,03 ppm e Se 0,86; 1,09; 0,72; 1,21; 0,91 e 0,75 ppm. Destes, os níveis de Co, Mn, Mo, Se e Zn foram considerados adequados para bovinos. Os níveis médios dos elementos no soro foram, para as quatro diferentes colheitas: Ca 118,72; 129,36; 125,19; 112,90; 96,76; 85,37 mg/L; P 109,28; 106,30; 117,03; 103,39; 115,78 e 107,75 mg/L; Mg 19,75; 23,62; 26,54; 20,96; 20,80 e 23,12 mg/L; K 139,64; 134,85; 114,19; 131,65; 130,57 e 116,60 mg/L; Cu 0,52; 0,73; 0,41; 0,59; 0,60 e 0,73 mg/L; Zn 1,19; 1,87; 1,38; 1,13;1,28 e 1,37 mg/L; Fe 2,52; 3,44; 2,21; 3,08; 3,00 e 2,89 mg/L e Se 1,19; 1,87; 0,19; 0,44, 0,40 e 0,51 mg/L...
The objective of the present work was to determinate the mineral levels in beef cattle blood serum (magnesium, copper, selenium, zinc, phosphorus, calcium, potassium, iron) and liver (cobalt, copper, selenium, manganese, molibdenium and zinc) at six different moments throughout sixteen months, to verify the occurrence of variation among them. Twenty-five half-breed nelore heifers, all of them about 18 months old, stayed during the experiment in the same Brachiaria brizantha pasture. They also received commercial mineral mixture in appropriate feeders and free acess to water. Pasture were also analised at the same moments we did for serum and liver (except february 2003). Water and mineral mixture were analised as well. The average levels of the elements in the liver, respectively for the six different moments: Co 0.27,0.27, 0.23, 0.21, 0.23 and 0.24 ppm; Mn 9.07, 8.55, 8.67, 8.40, 7.90 and 7.25 ppm; Mo 4.18, 3.85, 3.68, 3.32, 3.54, 3.19 ppm; Zn 113.4, 101.94, 97.91, 92.46, 88.29 and 81.74 ppm; Cu 40.76, 36.33, 24.50, 24.70, 77.75 and 128.03 ppm and Se 0.86, 1.09, 0.72, 1.21, 0.91 and 0.75 ppm. The levels of Co, Mn, Mo, Se and Zn were considered appropriate for cattle. The average levels of the elements in the serum were, for the six different moments: Ca 118.72, 129.36, 125.19, 112.90, 96.76, 85.37 mg/L; P 109.28, 106.30, 117.03, 103.39, 115.78 and 107.75 mg/L; Mg 19.75, 23.62, 26.54, 20.96, 20.80 and 23.12 mg/L; K 139.64, 134.85, 114.19, 131.65, 130.57 and 116.60 mg/L; Cu 0.52, 0.73, 0.41, 0.59, 0.60 and 0,73 mg/L; Fe 2,52; 3,44; 2,21; 3,08; 3,00 and 2,89 mg/L; Se 1.19, 1.87, 0.19, 0.44, 0.40 and 0.51 mg/L and Zn 1.19, 1.87, 1.38, 1.13,1.28 and 1.37 mg/L. In the serum, Ca, P, Mg, Zn, Fe and Se levels were considered appropriate for beef cattle. There was correlation between the hepatic and serum levels of Cu...(Complete abstract, click electronic address below)

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Peplow, Dan. "The influence of mine waste contamination on invertebrates and fish in the Methow River Valley, Okanogan County, Washington (U.S.A.) /." Thesis, Connect to this title online; UW restricted, 2003. http://hdl.handle.net/1773/5519.

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Moura, e. Silva Francisco César de. "Avaliação dos valores séricos e hepáticos de elementos minerais em novilhas nelore, criadas extensivamente, suplementadas com mistura mineral comercial /." Botucatu : [s.n.], 2007. http://hdl.handle.net/11449/89296.

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Orientador: Alexandre Secorun Borges
Banca: Márcio Rubens Graaf Kuchembuck
Banca: Ivan Roque de Barros Filho
Resumo: O presente trabalho teve como objetivo determinar os elementos minerais no soro sangüíneo (magnésio, cobre, selênio, zinco, fósforo, cálcio, potássio, ferro) e no tecido hepático (cobalto, cobre, selênio, manganês, molibdênio e zinco) em seis diferentes momentos durante um período de dezesseis meses e verificar se houve variação entre eles. Foram utilizadas 25 novilhas mestiças Nelore, com idade média de 18 meses, que permaneceram durante todo o tempo do experimento no mesmo pasto de Brachiaria brizantha. Os animais ainda receberam mistura mineral comercial em cocho coberto e água à vontade e foram submetidos à coleta de fragmentos hepáticos e sangue para obtenção de soro. Análises da pastagem também foram realizadas nos mesmos momentos em que foram colhidas as amostras de soro e fígado (exceto em fevereiro 2003). A água e o sal mineral também foram analisadas. Os níveis médios dos elementos no tecido hepático foram, respectivamente para as seis diferentes colheitas: Co 0,27;0,27; 0,23;0,21; 0,23 e 0,24 ppm; Mn 9,07; 8,55; 8,67; 8,40; 7,90 e 7,25 ppm; Mo 4,18; 3,85; 3,68; 3,32; 3,54; 3,19 ppm; Zn 113,4; 101,94; 97,91; 92,46; 88,29 e 81,74 ppm; Cu 40,76; 36,33; 24,50; 24,70; 77,75 e 128,03 ppm e Se 0,86; 1,09; 0,72; 1,21; 0,91 e 0,75 ppm. Destes, os níveis de Co, Mn, Mo, Se e Zn foram considerados adequados para bovinos. Os níveis médios dos elementos no soro foram, para as quatro diferentes colheitas: Ca 118,72; 129,36; 125,19; 112,90; 96,76; 85,37 mg/L; P 109,28; 106,30; 117,03; 103,39; 115,78 e 107,75 mg/L; Mg 19,75; 23,62; 26,54; 20,96; 20,80 e 23,12 mg/L; K 139,64; 134,85; 114,19; 131,65; 130,57 e 116,60 mg/L; Cu 0,52; 0,73; 0,41; 0,59; 0,60 e 0,73 mg/L; Zn 1,19; 1,87; 1,38; 1,13;1,28 e 1,37 mg/L; Fe 2,52; 3,44; 2,21; 3,08; 3,00 e 2,89 mg/L e Se 1,19; 1,87; 0,19; 0,44, 0,40 e 0,51 mg/L...(Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The objective of the present work was to determinate the mineral levels in beef cattle blood serum (magnesium, copper, selenium, zinc, phosphorus, calcium, potassium, iron) and liver (cobalt, copper, selenium, manganese, molibdenium and zinc) at six different moments throughout sixteen months, to verify the occurrence of variation among them. Twenty-five half-breed nelore heifers, all of them about 18 months old, stayed during the experiment in the same Brachiaria brizantha pasture. They also received commercial mineral mixture in appropriate feeders and free acess to water. Pasture were also analised at the same moments we did for serum and liver (except february 2003). Water and mineral mixture were analised as well. The average levels of the elements in the liver, respectively for the six different moments: Co 0.27,0.27, 0.23, 0.21, 0.23 and 0.24 ppm; Mn 9.07, 8.55, 8.67, 8.40, 7.90 and 7.25 ppm; Mo 4.18, 3.85, 3.68, 3.32, 3.54, 3.19 ppm; Zn 113.4, 101.94, 97.91, 92.46, 88.29 and 81.74 ppm; Cu 40.76, 36.33, 24.50, 24.70, 77.75 and 128.03 ppm and Se 0.86, 1.09, 0.72, 1.21, 0.91 and 0.75 ppm. The levels of Co, Mn, Mo, Se and Zn were considered appropriate for cattle. The average levels of the elements in the serum were, for the six different moments: Ca 118.72, 129.36, 125.19, 112.90, 96.76, 85.37 mg/L; P 109.28, 106.30, 117.03, 103.39, 115.78 and 107.75 mg/L; Mg 19.75, 23.62, 26.54, 20.96, 20.80 and 23.12 mg/L; K 139.64, 134.85, 114.19, 131.65, 130.57 and 116.60 mg/L; Cu 0.52, 0.73, 0.41, 0.59, 0.60 and 0,73 mg/L; Fe 2,52; 3,44; 2,21; 3,08; 3,00 and 2,89 mg/L; Se 1.19, 1.87, 0.19, 0.44, 0.40 and 0.51 mg/L and Zn 1.19, 1.87, 1.38, 1.13,1.28 and 1.37 mg/L. In the serum, Ca, P, Mg, Zn, Fe and Se levels were considered appropriate for beef cattle. There was correlation between the hepatic and serum levels of Cu...(Complete abstract, click electronic address below)
Mestre

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Ma, Yamin. "Vegetation as a biotic driver for the formation of soil geochemical anomalies for mineral exploration of covered terranes." University of Western Australia. School of Earth and Geographical Sciences, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0235.

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[Tuncated abstract] Soil is a relatively low cost and robust geochemical sampling medium and is an essential part of most mineral exploration programs. In areas of covered terrain, however, soils are less reliable as a sampling medium because they do not always develop the geochemical signature of the buried mineralisation; possibly a result of limited upward transport of ore related elements into the surficial overburden. As economic demands on the resources industry grow, mineral exploration continues to expand further into areas of covered terrain where the rewards of finding a new deposit relative to the risks of finding it may be comparatively low. Thus, improving the costeffectiveness of a geochemical exploration program requires a sound understanding of the mechanisms by which soil geochemical anomalies form in transported overburden. This thesis examines the deep biotic uplift of ore related elements by deep rooting vegetation as a mechanism for the development of soil geochemical anomalies within transported overburdens, in semi-arid and arid regions. '...' Vegetation and soils were analysed at two Au prospects in Western Australia: Berkley, Coolgardie and Torquata, 210 km south-east of Kambalda, in semi-arid Western Australia to complement both the mass balance and the differential modelling. At Berkley, both the vegetation and soils located directly over the mineralisation showed high concentrations of Au. There may be indirect evidence for the operation of the deep plant uptake flux taking effect from the field evidence at Berkley. Firstly, anomalous concentrations of Au were found in the surface soils, with no detectable Au in the transported overburden. Secondly, the trace element concentrations in vegetation showed correlation to the buried lithology, which to our knowledge has not been reported elsewhere. The results from the samples at Torquata, in contrast, were less conclusive because the Au is almost exclusively associated with a surficial calcrete horizon (at <5 m soil depth). Strong correlations of Ca and Au in leaf samples however, suggest that the vegetation may be involved in the formation of calcrete and the subsequent association of Au with the calcrete. Among the vegetation components, the litter and leaf samples gave the greatest anomaly contrast at both prospects. Finally, three main drivers for the deep biotic uplift of elements were identified based on the results from the mechanistic numerical modelling exercise: i) the deep uptake flux; ii) the maximum plant concentration and; iii) the erosional flux. The relative sizes of these three factors control the rates of formation and decay, and trace element concentrations, of the soil anomaly. The main implication for the use of soils as exploration media in covered terranes is that soil geochemical anomalies may only be transient geological features, forming and dispersing as a result of the relative sizes of the accumulative and loss fluxes. The thesis culminates in the development of the first quantitative, mechanistic model of trace element accumulation in soils by deep biotic uplift.

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KIRA, CARMEN S. "Estudo da composicao mineral e dos elementos-traco essenciais em amostras de leite e produtos lacteos por espectrometria de emissao atomica com plasma induzido e analise por ativacao com neutrons." reponame:Repositório Institucional do IPEN, 2002. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11040.

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Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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Silva, Felipe. "The Effects of Injectable Trace Mineral Supplements in Donor Cows at the Initiation of a Superovulation Protocol on Embryo Outcomes and Pregnancy Rates in Recipient Females." Thesis, North Dakota State University, 2018. https://hdl.handle.net/10365/28856.

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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.

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Nantapo, Carlos Wyson Tawanda. "Effect of stage of lactation on milk yield, somatic cell counts, mineral and fatty acid profiles in pasture-based Friesian, Jersey and Friesian × Jersey cows." Thesis, University of Fort Hare, 2012. http://hdl.handle.net/10353/d1006810.

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The effect of stage of lactation on milk yield, somatic cell counts, mineral and fatty acid profiles in pasture-based Friesian, Jersey and Friesian × Jersey cows was investigated. Twenty Friesian, twenty Jersey and twenty Friesian × Jersey cows were randomly selected from a dairy herd. A total of 202 milk samples were collected and analysed in three stages of lactation. Genotypic differences were observed in milk yield and fat content. Friesian cows produced the highest yield and lowest fat content whereas the opposite was true for Jersey cows (P<0.01). No significant differences were observed in SCC in the different genotypes, but SCC levels were higher in mid and late lactation (P<0.001). There was no effect (P<0.005) of genotype and stage of lactation interaction on Ca, P, Mg, Na, Mn and Bo concentration. Jersey cows had the least concentration of Fe and Cu in all stages of lactation. Strong positive correlations were observed among Ca and P, Mg and Zn. Aluminium had a strong positive relationship with Bo, Fe, Mn and Zn (P<0.001). Generally, SCC had a weak positive relationship with macro elements but a significant negative relationship with microelements. Yield levels were negatively correlated with Mg, Na, Al, Mn and SCC. Pasture ALA, SFA, n-3, n-6/n-3 and PUFA/MUFA concentration did not differ across the study period. Linoleic acid was highest in the second phase which coincides with mid lactation in cows (P<0.001). Highest moisture content coincided with the least fat free dry matter content in early lactation (P<0.001). Significantly high fat content was observed in late lactation than in early lactation. Highest butyric, caproic, linoleic, n-6 and PUFA were observed for Friesian cows. All other fatty acids ratios were not significantly different among different genotypes. Highest CLA, ALA, LA, SFA, PUFA, n-6, and n-3 and atherogenicity index were observed in early lactation whereas desaturase activity indices were highest in late lactation. Strong positive correlations were observed among milk vaccenic, ALA, LA and CLA concentrations. Inverse relationships were observed between SFA and long chain fatty acids. It can be concluded, it may be of advantage to consume milk from early stage of lactation poses a lower risk to coronary diseases and are much safer to consume.

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Griffault, Lise. "Bilan des transferts de matière (majeurs et terres rares) dans les altérations hydrothermales des granites : exemple du granite du ballon d'alsace (vosges méridionales)." Poitiers, 1987. http://www.theses.fr/1987POIT2302.

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Etude de deux systemes d'alteration hydrothermale: - une alteration pervasive, se manifestant par la chloritisation des ferromagnesiens, le formation d'illite dans les plagioclases et la cristallisation de calcite; - une alteration a illite dans les epontes de veines liees a la mise en place de filins de fluorine. Cette etude montre que le comportement geochimique des terres rares ne peut etre assimile au comportement des elements majeurs au cours des processus hydrothermaux ou des mineraux argileux sont formes. Les mecanismes de fixation des terres rares correspondent a des phenomenes de sorption des elements sur les surfaces des particules argileuses et non a des substitutions

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França, Elvis Joacir de. "A biomonitoração da Mata Atlântica na conservação da biodiversidade: espécies arbóreas nativas acumuladoras de elementos químicos." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/91/91131/tde-17102006-170028/.

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O projeto BIOTA Diversidade, dinâmica e conservação de florestas do Estado de São Paulo: 40 ha de parcelas permanentes vem sendo conduzido para o conhecimento dos processos geradores, mantenedores e reguladores da biodiversidade nas principais formações vegetacionais do Estado. Uma parcela permanente de 10 ha foi instalada na unidade de conservação correspondente à Floresta Ombrófila Densa (Mata Atlântica) para a caracterização completa do ecossistema. A investigação de elementos químicos nesse ecossistema altamente ameaçado foi desenvolvida nesta Tese de Doutoramento. Diversos processos são responsáveis pela manutenção de ecossistemas naturais. À ciclagem mineral corresponde o caminhamento dos elementos químicos, que fluem entre os compartimentos bióticos (folha e serrapilheira) e abióticos (atmosfera e solo). A complexidade desse mecanismo regulatório está relacionada com a deficiência, a toxicidade, a fitodisponibilidade e as interações dos elementos químicos, além das condições ambientais de crescimento como luminosidade, temperatura e umidade. Devido à sua adaptabilidade, as plantas absorvem elementos químicos, acumulando-os nos seus tecidos. A acumulação é ativa, ou seja, independentemente do meio, as plantas mantêm as concentrações de determinados elementos. Essa característica corrobora o uso desses organismos para a quantificação da qualidade do ambiente a partir dos estudos de biomonitoração de poluição atmosférica. A análise por ativação neutrônica instrumental INAA foi a técnica analítica empregada para a biomonitoração devido ao seu nível metrológico elevado e sua capacidade de determinação simultânea de diversos elementos. Para a comparabilidade dos resultados gerados, a qualidade do procedimento analítico, a representatividade das amostras e o efeito da contaminação com particulados de terra aderida à superfície das folhas foram também estudados. Os compartimentos solo, serrapilheira e folha tiveram sua composição química avaliada por INAA. De modo geral, foram detectadas concentrações totais de elementos químicos mais elevadas nos solos de vales (baixa altitude) do que nas regiões de alta altitude (solos mais desenvolvidos). Essa variabilidade não foi determinante das concentrações encontradas nas folhas, indicando a composição química elementar intrínseca das plantas. As concentrações nas folhas também não se alteraram significativamente (nível de 95% de confiança) de acordo com os resultados provenientes de quatro épocas de coleta diferenciadas. Foram identificadas espécies acumuladoras dos nutrientes Ca, Co, K, Na, Se e Zn, dos elementos traços Br, Ba, Cs, Hg, Rb, Sc, Sr e dos lantanídeos Ce, La e Sm. A utilização das espécies arbóreas para a biomonitoração da parcela permanente proporcionou o conhecimento das concentrações naturais dos elementos químicos. O trecho de Mata Atlântica avaliado foi considerado de baixo nível de poluição, pois a maior parte das espécies estudadas apresentou concentrações dos elementos químicos dentro da faixa esperada, com exceção das espécies naturalmente acumuladoras. Elementos traços como As, Cd, Cr e Ni ficaram abaixo dos limites de detecção. O trabalho concentrou esforços para o estabelecimento de padrões de referência para estudos de impacto ambiental considerando a composição química da parcela permanente da Mata Atlântica. O reservatório de elementos químicos no ecossistema foi estimado, evidenciando-se a importância desse conhecimento para a conservação da biodiversidade.
The BIOTA Project Diversity, dynamic and conservation of forests from the São Paulo State: 40 ha of permanent parcels has been conducted to provide the knowledge on the generation, sustainability and regulation processes of the biodiversity of the State. A long-term plot (permanent parcel) was installed in the conservation unit corresponding to the Dense Ombrophilous Forest (Atlantic Forest) for the environmental characterization of the ecosystem. The investigation of chemical elements in this highly threatened forest was performed in this Doctorate Thesis. Several processes are responsible for the sustainability of the natural ecosystems. Mineral cycling defines the pathway of chemical elements from non-biotic compartments (soil and atmosphere) to biotic compartments (leaf and litter). The complexity of this regulatory mechanism is related to the deficiency, toxicity, phytoavailability and the interactions of the chemical elements, in addition to environmental growth conditions like luminosity, temperature and humidity. Due to its adaptability, plants are able to uptake and accumulate chemical elements in their tissues. This accumulation is an active process in which the plants tend to maintain the concentrations of some chemical elements independently of the environmental conditions. Such characteristic corroborates the use of these organisms for quantifying the environmental quality by biomonitoring studies of atmospheric pollution. Instrumental neutron activation analysis INAA was the analytical technique employed for biomonitoring due to its high metrological level and its capability for simultaneous determination of several chemical elements. For the comparability of the results, the quality of analytical procedure, the representativeness of samples and the effect of contamination with earth particles adhered to the leaf surface were also studied. The chemical composition of the soil, litter and leaf compartments was evaluated by INAA. The concentrations of some elements were higher for the soils of the valleys and considerably lower for the soils at higher altitudes. Such variability was not observed for the concentrations found in leaves, indicating the intrinsic chemical composition in plants. The concentrations in leaf did not change significantly (at the 95% confidence level) as demonstrated by the results from four different periods of sampling. Some tree species were able to accumulate the nutrients Ca, Co, K, Na, Se and Zn, the trace elements Br, Ba, Cs, Rb, Sc and Sr and the lanthanides Ce, Eu, La, Sm, Tb and Yb. The use of plants species for biomonitoring the long-term plot provided knowledge on the background concentrations of chemical elements. The Atlantic Forest can be considered to have a low status of pollution since most plants have shown concentrations within the expected range with exception of the accumulator species. Concentrations of some trace elements like As, Cd, Cr and Ni were below the detection limits. This work concentrated efforts to establish reference standards for studies on environmental impact considering the chemical composition in the long-term plot of the Atlantic Forest. The reservoir of chemical elements in the ecosystem was estimated, evidencing the importance of such knowledge for the biodiversity conservation.

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Bosze, Stephanie Lynn. "SURFACE STRUCTURALLY CONTROLLED SECTORAL ZONING IN FLUORITE: IMPLICATIONS TO UNDERSTANDING HETEROGENEOUS REACTIVITY AT THE MINERAL-WATER INTERFACE." Oxford, Ohio : Miami University, 2001. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=miami981052842.

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Nelson, Wendy Rae. "Mineral-Scale Sr Isotopic Study of Plagioclase in the Mafic Dikes of the North American Wall and the Diorite of the Rockslides, Yosemite Valley, California." Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1204.pdf.

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21

Hartung, Eva. "Early magmatism and the formation of a ‘Daly Gap’ at Akaroa Shield Volcano, New Zealand." Thesis, University of Canterbury. Geological Sciences, 2011. http://hdl.handle.net/10092/5584.

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The origin of compositional gaps in volcanic deposits remains controversial. In Akaroa Volcano (9.6 to 8.6 Ma), New Zealand, a dramatic compositional gap exists between basaltic and trachytic magmas. Previously, the formation of more evolved magmas has been ascribed to crustal melting. However, the interpretation of new major and trace element analysis from minerals and bulk-rocks coupled with the mechanics of crystal-liquid separation offers an alternative explanation that alleviates the thermal restrictions required for crustal melting models. In a two-stage model, major and trace element trends can be reproduced by polybaric crystal fractionation from dry melts (less than 0.5 wt.% H2O) at the QFM buffer. In the first stage, picritic basalts are separated from an olivine-pyroxene dominant mush near the crust-mantle boundary (9 to 10 kbar). Ascending magmas stagnated at mid-crustal levels (5 to 6 kbar) and fractionated an olivine-plagioclase assemblage to produce the alkali basalt-hawaiite trend. In the second stage, trachyte melt is extracted from a crystal mush of hawaiite to mugearite composition at mid-to-upper crustal levels (3 to 5 kbar) after the melt has crystallised 50 vol.%. The fractionated assemblage of plagioclase, olivine, clinopyroxene, magnetite, and apatite is left in a cumulate residue which corresponds to the mineral assemblage of sampled ultramafic enclaves. The results of trace element modelling of Rayleigh fractionation using this extraction window is in close agreement with the concentrations measured in trachyte (= liquid) and enclaves (= cumulate residue). The compositional gap observed in the bulk-rock data of eruptive products is not recorded in the feldspar data, which show a complete solid solution from basalt and co-magmatic enclaves to trachyte. Complexly zoned plagioclases further suggest episodical magma recharge events of hotter, more mafic magmas, which lead to vigorous convection and magma mixing. In summary, these models indicate that the Daly Gap of Akaroa Volcano formed by punctuated melt extraction from a crystal mush at the brittle-ductile transition.

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Yang, Panseok. "Trace element partitioning between coexisting metamorphic minerals and trace element zoning in metamorphic minerals from Gagnon Terrane, western Labrador /." Internet access available to MUN users only, 2002. http://collections.mun.ca/u?/theses,35173.

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Akinyemi, Segun Ajayi. "Geochemical and mineralogical evaluation of toxic contaminants mobility in weathered coal fly ash: as a case study, Tutuka dump site, South Africa." Thesis, University of the Western Cape, 2011. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_1226_1360593017.

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The management and disposal of huge volumes of coal combustion by products such as fly ash has constituted a major challenge to the environment. In most cases due to the inadequate alternative use of coal fly ash, the discarded waste is stored in holding ponds, slag heaps, or stock piled in ash dumps. This practice has raised concerns on the prospect of inorganic metals release to the surface and groundwater in the vicinity of the ash dump. Acceptable scientific studies are lacking to determine the best ash disposal practices. Moreover, knowledge about the mobility patterns of inorganic species as a function of mineralogical association or pH susceptibility of the dry disposed ash dump under natural weathering conditions are scarce in the literature. Fundamental understanding of chemical interactions of dry disposed ash with ingressed CO2 from atmosphere, percolating rain water and brine irrigation within ash disposal sites were seen as key areas requiring investigation. The mineralogical association of inorganic species in the dry disposed ash cores can be identified and quantified. This would provide a basis for understanding of chemical weathering, mineralogical transformations or mobility patterns of these inorganic species in the dry ash disposal scenario. The current study therefore aims to provide a comprehensive characterisation of weathered dry disposed ash cores, to reveal mobility patterns of chemical species as a function of depth and age of ash, with a view to assessing the potential environmental impacts. Fifty-nine samples were taken from 3 drilled cores obtained respectively from the 1 year, 8 year and 20-year-old sections of sequentially dumped,
weathered, dry disposed ash in an ash dump site at Tutuka - a South African coal burning power station. The core samples were characterized using standard analytical procedures viz: X-ray fluorescence (XRF), X-ray diffraction (XRD), Fourier transforms infrared (FTIR) techniques, Scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS) and Acid neutralisation capacity (ANC) test. A modified sequential extraction (SE) method was used in this study. The chemical partitioning, mobility and weathering patterns in 1 year, 8 year and 20-year-old sections of the ash dump were respectively investigated using this modified sequential extraction scheme. The sequence of the extractions was as follows: (1) water soluble, (2) exchangeable, (3) carbonate, (4) iron and manganese and (5) residual. The results obtained from the 5 steps sequential extraction scheme were validated with the total metal content of the original sample using mass balance method. The distribution of major and trace elements in the different liquid fractions obtained after each step of sequential extraction of the 59 drilled core samples was determined by inductively coupled plasma mass spectrometry (ICPMS). The data generated for various ash core samples were explored for the systematic analysis of mineralogical transformation and change in ash chemistry with ageing of the ash. Furthermore, the data was analyzed to reveal the impact of ingressed CO2 from atmosphere, infiltrating rain water and brine irrigation on the chemistry of ash core samples. Major mineral phases in original ash core samples prior to extraction are quartz (SiO2) and mullite (3Al2O3·
2SiO2). Other minor mineral phases identified were hematite (Fe2O3), calcite (CaCO3), lime (CaO), anorthite (CaAl2Si2O8), mica (Ca (Mg, Al)3 (Al3Si) O10 (OH)2), and enstatite (Mg2Si2O6). X-ray diffraction results show significant loss of crystallinity in the older ash cores. The presence of minor phases of calcite and mica in dry disposed ash cores are attributed to reduction in the pore water pH due to hydration, carbonation and pozzolanic reactions. The X-ray diffraction technique was unable to detect Fe-oxyhydroxide phase and morealuminosilicate phases in ash core samples due to their low abundance and amorphous character. X-ray fluorescence results of the original ash core samples showed the presence of major oxides, such as SiO2, Al2O3, Fe2O3, while CaO, K2O, TiO2, Na2O, MnO, MgO, P2O5, and SO3 occur in minor concentrations. The ratio of SiO2/Al2O3 classified the original core samples prior to extraction as a silico-aluminate class F fly ash. The ternary plot of major elements in 1-year-old ash core samples was both sialic and ferrocalsialic but 8 year and 20-year-old ash core samples were sialic in chemical composition. It is noteworthy that the mass % of SiO2 varies through the depth of the core with an increase of nearly 3 %, to 58 mass % of SiO2 at a depth of 6 m in the 1-year-old core whereas in the case of the 8-year-old core a 2 % increase of SiO2 to a level of 57.5 mass % can be observed at levels between 4-8 m, showing dissolution of major components in the matrix of older ash cores.. The Na2O content of the Tutuka ash cores was low and varied between 0.6-1.1 mass % for 1-year-old ash cores to around 0.6-0.8 mass % for 8-year-old ash cores. Sodium levels were higher in 1-year-old ash cores compared to 8 year and 20-year-old ashcores. Observed trends indicate that quick weathering of the ash (within a year) leached out Na+ from the ash dump. No evidence of Na+ encapsulation even though the ash dump was brine irrigated. Thus the dry disposal ash placement method does not result in a sustainable salt sink for Na-containing species over time. The total content of each of the elements in 1 year and 20-year-old ash cores was normalised with their total content in fresh ash from same power station to show enrichment and depletion factor. Major elements such as K+, Mn showed enrichment in 1-year-old ash cores whereas Al, Si, Na+, Ti, Ca, Mg, S and Fe showed depletion due to over time erosion. Trace elements such as Cr, Sr, P, Ba, Pb, V and Zn showed enrichment but Ni, Y, Zr showed depletion attributed to over time erosion. In 20-year-old ash cores, major elements such as Al, Na+ and Mn showed enrichment while Si, K+, Fe, Mg and Ca showed depletion highlighting their mobility. Trends indicated intensive flushing of major soluble components such as buffering constituents (CaO) by percolating rain water. The 1-year-old and 20-year-old coal ash cores showed a lower pH and greater loss/depletion of the soluble buffering constituents than the 2-week-old placed ash, indicating significant chemical weathering within a year. Based
on ANC results the leaching behaviours of Ca, Mg, Na+, K+, Se, Cr, and Sr were found to be controlled by the pH of the leachant indicating high mobility of major soluble species in the ash cores when in contact with slightly acid rain water. Other investigated toxic metals such as As, Mo and Pb showed amphoteric behaviour with respect to the pH of the leachant. Chemical alterations and formation of transient minor secondary mineral phases was found to have a significant effect on the acid susceptibility and depletion pattern of chemical species in the core ash samples when compared to fresh ash. These ANC results correlated well with the data generated from the sequential extraction scheme. Based on sequential extraction results elements, showed noticeable mobility in the water soluble, exchangeable and carbonate fractions due to adsorption and desorption caused by variations in the pore water pH. In contrast, slight mobility of elements in the Fe and Mn, and residual fractions of dry disposed fly ashes are attributed to the co-precipitation and dissolution of minor amount of less soluble secondary phase overtime. The 1-year-old dry disposed ash cores were the least weathered among the 3 drilled ash cores. Therefore low concentration of toxic metals in older ash cores were ascribed to extensive weathering with slower release from residual mineral phases over time. Elements were found to associate with different mineral phases depending on the age or depth of the core samples showing greater heterogeneity in dispersion. For instance the average amount of total calcium in different mineral associations of 1-year-old ash cores is as follows
water soluble (10.2 %), exchangeable (37.04 %), carbonate (37.9 %), Fe and Mn (7.1 %) and residual (2.97 %). The amount of total Na+ in different mineral phases of 1-year-old ash cores followed this trend: water soluble (21 %), exchangeable (11.26 %), carbonate (2.6 %), Fe and Mn (4.7 %) and residual (53.9 %). The non-leachable portion of the total Na+ content (namely that contained in the residual fraction) in the 1-year-old ash core samples under conditions found in nature ranged between 5-91 %. This non-leachable portion of the Na+ showed the metastability of the mineral phases with which residual Na+ associates. Results showed older ash cores are enriched in toxic elements. Toxic elements such as As, B, Cr, Mo and Pb are enriched in the residual fraction of older ash cores. For instance As concentration in the residual fraction varied between 0.0003- 0.00043 mg kg-1 for 1-year-old ash cores to around 0.0003-0.0015 mg kg-1 for 20-year-old ash cores. This suggests that the older ash is enriched in toxic elements hence dust from the ash dump would be toxic to human health. The knowledge of mobility and ecotoxicological significance of coal fly ash is needed when considering its disposal or reuse in the environment. The mobility and ecotoxicology of inorganic metals in coal fly ash are determined by (i) mineralogical associations of inorganic species (ii) in-homogeneity in the ash dumps (iii) long and short term exposure to ingress CO2 and percolating rain water. Management issues such as inconsistent placement of ash in the dumps, poor choice of ash dump site, in-homogeneity in brine irrigation, no record of salt load put on the ash dumps and lack of proper monitoring requires improvement. The thesis provides justification for the use of the modified sequential extraction scheme as a predictive tool and could be employed in a similar research work. This thesis also proved that the dry ash disposal method was not environmental friendly in terms of overall leaching potential after significant chemical weathering. Moreover the study proved that the practice of brine co-disposal or irrigation on ash dumps is not sustainable as the ash dump did not act as a salt sink.

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24

Hassani, Bibizahra 1959. "Binding of trace elements with various dietary fiber sources." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/277058.

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Mineral binding capacity of rice bran, oat hull, soy bran, wheat bran, peanut, apple, tomato, and barley fiber were investigated. Defatted fibers were analyzed for ash, protein, acid detergent fiber, and lignin. The fibers were washed with 1% HCl and Acid washed samples were studied for their mineral binding ability. The minerals tested were zinc, copper, and magnesium. Analysis of acid washed samples showed that most of the original minerals had been stripped from the fiber. In most of the fibers studied, the order of binding was copper > zinc > magnesium. Among the eight fibers studied, oat hull and apple fiber had the lowest consistent binding capacity for the three minerals investigated. This in vitro binding study has been run to duplicate intestinal condition of pH 6.8.

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25

Bouch, Jonathan E. E. "Trace element geochemistry of authigenic heavy minerals in reservoir sandstones." Thesis, University of Aberdeen, 1996. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU089767.

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Authigenic growths of heavy minerals, crystallised under relatively low temperature diagenetic conditions have been recognised in a number of sedimentary sequence. A range of microbeam techniques have revealed trace element geochemical variations on several scales in authigenic titanites and apatites. These variations occur, within individual cement grains and patches, within a single sedimentary sequence, and between different sedimentary sequences. Mixed fluvial-aeolian, Permian, sediments at the Cock of Arran (Isle of Arran, Scotland) contain pore filling titanite cements. The titanites show a range of zoning patterns, dominated by compositional sector zones. The sector zones are defined by large (order of magnitude) differences in rare earth element (REE) and high field strength element (HFSE) concentrations between titanite grown at different crystal faces. The mechanism responsible for sector zone formation is considered to relate to differences in the surface structure of titanite at different crystal faces. Faces of the forms { 100 } and { 001 } are likely to have surface configurations more amenable for impurity element incorporation than faces of the form { 161 }. This evidence for disequlibirium titanite growth, and the large differences which must exist between effective partition coefficients at different titanite crystal faces, makes models of equilibrium trace element partitioning effectively meaningless. Minor growth zones are also present and relate to subtle differences in the REE composition of the titanite. These variations have been used to construct a model of titanite-fluid REE partitioning which suggests that the HREE have higher effective titanite-fluid partition coefficients than the LREE. In the continental Statfjord Formation (Jurassic, North Viking Graben) authigenic apatite occurs as overgrowths on variably corroded detrital cores. The authigenic apatite is chemically very distinct from the detrital apatite and contains high concentrations of Sr, REE, F, and probable concentrations of C.

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26

Sze, Kwan-Lok, and 施均樂. "Electrophoretic methodologies for the determinations of minerals and trace elements in milk." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B43085246.

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Ahmed, Shafiqur Rahman. "Studies on metabolism of minerals and trace elements in vitamin A deficiency." Kyoto University, 1997. http://hdl.handle.net/2433/202192.

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Sze, Kwan-Lok. "Electrophoretic methodologies for the determinations of minerals and trace elements in milk." Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B43085246.

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ROCKWAY, SUSIE WILSON. "INTERACTION AND BIOAVAILABILITY OF TRACE MINERALS WITH CEREAL BRANS (FIBER, COPPER)." Diss., The University of Arizona, 1985. http://hdl.handle.net/10150/187963.

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The ability of wheat bran and oat hulls to bind copper and zinc using a new chromatographic technique was investigated and compared to a centrifugation method. Also investigated was the bioavailability of copper which had been exogenously bound to wheat bran then fed to mice and rats. Wheat bran bound 6 mg Cu/g fiber when pH was raised to 7. Less binding occurred at lower pHs. Seven mg of zinc bound to wheat bran at pH 5 while only a trace bound at pH less than 2. Oat hulls bound 3 mg Cu/g fiber at pH 5, and less than 1 mg of zinc bound per g of oat hull at pH 6. Binding for both fibers depended on the level of mineral added to the fiber slurry during incubation. But only wheat bran binding capacity was influenced by pH. The two methods used did not compare favorably, in all cases, to the amount of mineral bound to fiber. Copper when bound to wheat bran, was utilized in both species, with differences occurring between species was noted. Rats fed the copper bound diet compared favorably with rats fed the copper-adequate diet as determined by body weight, weight gain, heart weight, liver copper concentration and heart copper concentration. Mice, on the other hand showed similar liver and heart concentrations of copper for mice fed either the copper-bound diet or the copper-adequate diets. The in vitro results showed that binding of copper or zinc to wheat bran occurred at a pH similar to the intestinal pH and wheat bran binds more copper and zinc than oat hulls. Oat hulls may prove to be a better dietary fiber source for those people who need to increase their dietary fiber, because oat hulls do not appear to bind copper or zinc and would not likely impair their absorption. Although wheat bran had a high binding capacity for copper, this binding did not significantly inhibit copper absorption as determined in animal studies suggesting that fiber-mineral binding (at least for copper bound to wheat bran) does not cause mineral deficiency symptoms as claimed by many researchers.

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30

Zack, Thomas. "Trace element mineral analysis in high pressure metamorphic rocks from Trescolmen, Central Alps." [S.l. : s.n.], 1999. http://deposit.ddb.de/cgi-bin/dokserv?idn=963753924.

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31

Dabbs, Jennifer Marie, and Jennifer Marie Dabbs. "Trace Element Composition of Apatite from Intrusive Rocks in Northeastern Nevada, USA." Thesis, The University of Arizona, 2016. http://hdl.handle.net/10150/620842.

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The apatite crystal structure-A5(TO4)3X-allows for complex substitutions of various minor and trace elements including volatile constituents, rare earth elements, and redox sensitive elements (e.g., As, Mn, Fe, S) (Piccoli and Candela, 1994; Piccoli and Candela, 2002; Pan and Fleet, 2002; Teiber et al., 2015; Harlov, 2015). In this study, apatite grains from 19 intrusions across northeastern Nevada with varied petrogenetic and metallogenic properties were analyzed by electron probe microanalysis (EPMA) to obtain major and trace element abundances. Systematic variations in Sr and REE concentrations in apatite grains from granitic host rocks are the result of competition with pre-existing and coexisting minerals in silicate melts. The presence of zoning in cathodoluminescence colors combined with high Sr concentrations in apatite from many of the Eocene granodiorite rocks suggest magma mixing affected the geochemical evolution in many of the Eocene igneous systems. In addition, high Sr concentrations in apatite grains from Late Cretaceous two-mica granites may reflect significant magmatic input from lower crustal and/or mantle sources despite the felsic nature of these intrusive rocks.A new EPMA analytical routine to measure arsenic down to detection limits of approximately 20 ppm allowed a more extensive characterization of As concentration in igneous apatite than has previously been published. Still, correlations between As and other trace-element concentrations are not evident, which may reflect the simple substitution of As5+ for P5+ in the apatite structure. Petrologic controls on As content include redox state, indicated by the high Asapat/Asbulk-rock in relatively oxidized intrusive rocks. An additional control is competition among other magmatic phases, exsolving aqueous fluids, or sulfide melts, indicated by enrichment of As in apatite cores relative to apatite rims. Past studies on redox-sensitive elements in igneous apatite have focused on Mn and S, but with further investigation, As may also prove to be a key redox-sensitive trace element in apatite for interpreting igneous and hydrothermal processes.

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32

Smith, Cornel. "The effect of preserving liver tissue in formalin on the concentration of trace minerals in the liver." Pretoria : [s.n.], 2005. http://upetd.up.ac.za/thesis/available/etd-08052005-101056/.

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33

Evans, Guy Nathaniel. "Trace element proxies and mineral indicators of hydrothermal fluid composition and seafloor massive sulfide deposit formation processes." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/111731.

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Thesis: Ph. D. in Marine Geology, Joint Program in Marine Geology and Geophysics (Massachusetts Institute of Technology, Department of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), 2017.
Cataloged from PDF version of thesis.
Includes bibliographical references.
This thesis analyzes compositions of seafloor massive sulfide (SMS) deposits and related hydrothermal vent fluids to identify proxies of reaction zone conditions (host-rock lithology, hydrothermal fluid temperature and chemistry). Chapter 2 investigates the morphology, mineralogy, and geochemistry of SMS deposits from six vent fields along the Eastern Lau Spreading Center (ELSC), demonstrating that ELSC SMS deposits record differences in hydrothermal fluid temperature, pH, sulfur fugacity and host-rock lithology related to proximity to the nearby Tonga Subduction Zone. Chapters 3 and 4 focus on partitioning of Co, Ni, Ga, Ag, and In between hydrothermal vent fluids and chalcopyrite lining fluid conduits in black smoker chimneys. Chapter 3 develops secondary ion mass spectrometry (SIMS) as a technique to measure Co, Ni, Ga, Ag, and In in chalcopyrite and identifies a correlation between Ga and In in chalcopyrite and hydrothermal fluid pH. Chapter 4 presents new data on these elements in ELSC hydrothermal fluids that, combined with SIMS analyses of chalcopyrite chimney linings and previously published data on vent fluids from the Manus Basin, provide evidence that supports partitioning of Ag a lattice substitution for Cu. Together, concentrations of Ga, In, and Ag in chalcopyrite provide proxies of hydrothermal fluid pH and metal (i.e., Ag and Cu) contents.
by Guy Nathaniel Evans.
Ph. D. in Marine Geology

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34

Moretto, Robert. "Étude sédimentologique et géochimique des dépôts de la série salifère paléogène du bassin de Bourg-en-Bresse (France)." Nancy 1, 1986. http://www.theses.fr/1986NAN10393.

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On étudie la série salifère paléogène du bassin de Bourg-en-Bresse par diverses méthodes. L'analyse diagraphique permet d'établir des corrélations spatiales entre les différents ensembles de cette série. Des études pétrographiques, faciologiques, sédimentologiques, minéralogiques et géochimiques détaillées permettent de mieux appréhender les modalités de la sédimentation évaporitique dans le fossé bressan et de proposer un schéma de son évolution au cours du paléogène

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35

Monnin, Christophe. "Thermodynamique des eaux naturelles concentrees : solubilite des mineraux a haute temperature et a haute pression et coefficients d'activite des elements en trace." Toulouse 3, 1989. http://www.theses.fr/1989TOU30073.

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Applications geochimiques du modele de pitzer au domaine hydrothermal et aux elements en faible concentration. Mise en evidence de la capacite du modele a predire les densites des solutions et les volumes molaires partiels des solutes a partir de la seule connaissance des proprietes des solutions binaires. Le modele est etendu jusqu'a 200 pour le systeme na-ca-cl-so#4-h#2o. Apres l'estimation des compressibilites molaires partielles, on est en mesure de calculer la variation des coefficients d'activite avec la pression jusqu'a 200 et 1 kbar, ce qui permet de calculer la solubilite de l'anhydrite. L'application du modele aux saumures de la mer rouge a permis de montrer que l'anhydrite est a l'equilibre avec la saumure inferieure de la fosse atlantis ii. On propose un modele de calcul des coefficients d'activite des elements en faible concentration qui permet de calculer avec precision la solubilite des sulfates de baryum et de strontium dans les eaux naturelles

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36

Schröder, Annette [Verfasser], and Gerhard [Akademischer Betreuer] Schmiedl. "Changes of clay mineral and trace element characteristics of sinking particulate matter during transport into the Deep South China Sea / Annette Schröder. Betreuer: Gerhard Schmiedl." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2016. http://d-nb.info/1095766333/34.

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37

Schröder, Annette Verfasser], and Gerhard [Akademischer Betreuer] [Schmiedl. "Changes of clay mineral and trace element characteristics of sinking particulate matter during transport into the Deep South China Sea / Annette Schröder. Betreuer: Gerhard Schmiedl." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2016. http://d-nb.info/1095766333/34.

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38

Robert, Maya [Verfasser], Dieter [Akademischer Betreuer] Wolf-Gladrow, Victor [Gutachter] Smetacek, and Uta [Gutachter] Passow. "Importance of Polysaccharides for the cycling of Minerals and trace elements in the ocean / Maya Robert ; Gutachter: Victor Smetacek, Uta Passow ; Betreuer: Dieter Wolf-Gladrow." Bremen : Staats- und Universitätsbibliothek Bremen, 2010. http://d-nb.info/1154925927/34.

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39

Robert, Maya [Verfasser], Dieter [Akademischer Betreuer] Wolf-Gladrow, Uta [Gutachter] Passow, and Victor [Gutachter] Smetacek. "Importance of polysaccharides for the cycling of minerals and trace elements in the ocean / Maya Robert ; Gutachter: Uta Passow, Victor Smetacek ; Betreuer: Dieter Wolf-Gladrow." Bremen : Staats- und Universitätsbibliothek Bremen, 2010. http://d-nb.info/1162620609/34.

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40

Franzan, Renata. "Preparação e caracterização físico-química de complexos de hidrolisados parciais de proteína com minerais." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/60/60137/tde-02062008-104546/.

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Os minerais essenciais participam de várias funções vitais do organismo, suas deficiências contribuem de maneira significante para a morbidade e mortalidade na infância, especialmente nos países em desenvolvimento, sendo consideradas como problema de saúde pública em todo o mundo. Minerais apresentados na forma de complexos orgânicos têm sido propostos para correção destas deficiências por apresentarem maior biodisponibilidade, quando comparados aos equivalentes sais inorgânicos. Os minerais cobre, ferro, manganês e zinco são essenciais aos organismos vivos (humano e animal), a manutenção de seus níveis de acordo com as necessidade fisiológicas contribuem para a manutenção da saúde, resultando em benefícios econômicos. No presente trabalho foi realizada a preparação e caracterização físico-química de complexos dos minerais Cobre (Cu), Ferro (Fe), Manganês (Mn) e Zinco (Zn) com hidrolisados parciais de proteína de soja. As hidrólises utilizando as enzimas Aranzime e Alcalase foram mais eficientes que as demais hidrólises enzimáticas ou ácidas, entretanto somente a Alcalase foi aprovada para a manufatura de produtos alimentares de consumo humano. A coordenação entre os metais e o hidrolisado pode ser confirmada por pelo deslocamento das bandas ?NH2, ?aCOO- e ?sCOO-. Os complexos obtidos de cobre, ferro, manganês e zinco, posuem em sua composição os respectivos percentuais de ligação: 2,21%, 1,22%, 12,38% e 10,40%.
The essential minerals participate in many vital functions in the organism, its deficiencies contribute in significant way for the morbidity and mortality in the childhood, especially in developing countries, being considered as public health problem in the whole world. Minerals presented in the form of organics complexes have been considered a good choice for these deficiencies, because it presents greater bioavailability when compared with the equivalents inorganic salts. The minerals copper, iron, manganese and zinc are essential to the organisms (human and animal), its physiological levels in accordance with the necessity contribute for the health maintence, resulting in economical benefits. In the present work it was carried through preparation and physical and chemical characterization of mineral complexes of Copper (Cu), Iron (Fe), Manganese (Mn) and Zinc (Zn) with partial hydrolysates of soy protein. The hydrolyses using the Aranzime and Alcalase enzymes had been more efficient than other enzymatic or acid hydrolyses, however only the Alcalase enzyme is approved for the manufacture of alimentary products for human consumption. Coordination between metals and the hydrolysate can be confirmed by the displacement of the ?NH2, ?aCOO- and ?sCOO- bands. The gotten copper, iron, manganese and zinc complexes, had the respective percentages of metal in its composition: 2,21%, 1,22%, 12,38% e 10,40%.

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41

Thorette, Jacques. "Contribution à l'étude de l'hydrothermalisme océanique : exemple du district minéralisé de York-Harbour (massif ophiolitique de Blow-Me-Down, Bay-of-Islands, Terre-Neuve)." Brest, 1986. http://www.theses.fr/1986BRES2002.

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Les mineralisations a cu-fe-zn de york-harbour sont encaissees dans l'unite volcanique situee au sommet de l'ophiolite cambrienne de blow-me-down. Celle-ci s'est formee a l'axe d'une dorsale oceanique a proximite d'une faille transformante. L'organisation en synclinal du secteur mineralise resulte du rejet des failles synvolcaniques en direction nord 135 et nord 45

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42

Benzaazoua, Mostafa. "Caractérisation physico-chimique et minéralogique de produits miniers sulfurés en vue de la réduction de leur toxicité et de leur valorisation." Vandoeuvre-les-Nancy, INPL, 1996. http://docnum.univ-lorraine.fr/public/INPL_T_1996_BENZAAZOUA_M.pdf.

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Des minerais sulfurés de la ceinture pyriteuse Sud-Ibérique et à or réfractaire ont été analysés à l'échelle microscopique. Les microscopes optique et électronique à balayage, couplés aux microsondes électronique et ionique ont permis d'étudier les teneurs et la répartition d'éléments en traces, tels l'indium et l'or. Des mises au point analytiques ont du être effectués: les interférences spectrales en MSE et de masse en MSI ont été étudiées en détail et il a aussi pu être démontré que le statut cristallochimique de l'or dans une matrice donnée peut influencer l'émission ionique, avec pour conséquence des erreurs possibles de quantification. La spectroscopie Mössbauer de 119Sn s'avère aussi utile dans le cas des paragenèses stannifères ou au moins deux états de l'étain sont présents. Le microscope électronique à transmission apporte, quant à lui, une contribution déterminante dans l'étude de l'or combiné associé à FeAsS. Les conclusions partielles de ces études minéralogiques de détail permettent, dans le cas des sulfures de la mine de Neves Corvo par exemple, de tirer des conclusions utiles aux exploitants miniers, en permettant la confection de bilans de répartition éléments en traces-minéraux porteurs. La question du potentiel polluant des rejets sulfures à pyrite et/ou arsénopyrite a été aussi abordée dans la perspective de dégager des informations qualitatives et quantitatives prévisionnelles. Aux techniques mentionnées plus haut sont venues se rajouter des méthodes de caractérisation des tailles, des surfaces, de la réponse électrochimique et électrique des solides, de la flore microbienne. L’altérabilité d'un stérile peut ainsi être définie en parallèle ou même en préalable aux études de lixiviation. Enfin, les mortiers de stabilisation/solidification par un liant hydraulique de stériles arséno-pyriteux ont été caractérisés, du point de vue de leur microstructure et de leur composition chimique après lixiviation accélérée au laboratoire. L'étude microscopique en lumière réfléchie, l'analyse quantitative des variations élémentaires au sein des fronts dans différentes matrices ont permis de dégager les tendances générales et particulières de l'évolution de l'altération. La rétention d'arsenic est mise en évidence à la fois par DRX et microscopie électronique

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43

MacDonald, James Douglas. "The partitioning of Cd, Cu, Pb and Zn between the solid and solution phase of forest floor horizons in podzolic soils near metal smelters /." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=85575.

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The emission of trace metals (TMs) into boreal forest regions of the northern hemisphere is an important environmental issue due to their potential detrimental impacts on these sensitive ecosystems. One of the foremost factors controlling metal cycling is the chemistry of the overlying organic forest floor of the forest soil. In this thesis we examine the chemistry of forest floor horizons of podzolic soils. Our goal is to improve our ability to predict the partitioning of metals between the soil solid and solution phases.
We developed a standard protocol to produce solutions that resemble lysimeter solutions from podzolic soils using air-dried samples. We hypothesized that the stabilization point of the electrical conductivity (EC) of the soil solution is indicative of the point in which soluble salts and organic material precipitated during sampling and storage are removed from the soil particle surfaces. Solutions produced by leaching the soils, once the EC of wash solutions had stabilized, were comparable to lysimeter solutions from the area where samples were collected with respect to the concentrations of divalent cations, pH, EC and dissolved organic carbon (DOC). The applicability of this procedure to trace metal partitioning in forest floors was explored. Laboratory extractions produced partition coefficients (log Kd) similar to observed lysimeter solutions ranging from 3.4 to 3.9 for Cd, 3.4 to 3.9 for Cu, 3.4 to 4.1 for Ni, 4.1 to 5.2 for Pb and 3.2 to 3.5 for Zn. According to a semi-mechanistic regression model based on observed lysimeter concentrations, the metal concentrations in solution were appropriate relative to known factors that influence metal partitioning in soils: pH, the concentrations of total metals and DOC.
While chemical characteristics of soils have been consistently observed to play important roles in the partitioning and toxicity of metals we wished to place the importance of the chemical characteristics of soil on mobility and toxicity in context. We interpreted field data that had been collected from transects established with distance from two point source emitters in Rouyn PQ, and Sudbury ON. Canada find developed equations that predict dissolved metal concentrations from total metal concentrations, soil pH, soil organic matter (SOM), and DOC contents. We integrated these equations into a simple box model that calculates changes in the concentration of metals in the organic and upper mineral horizons and includes a loop for vegetative return of metals to the forest floor.

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44

Ver, Hoeve Thomas James. "Applications of LA-ICP-MS analysis to zircon : assessing downhole fractionation and pre-treatment effects for U-Pb geochronology and trace element variations in accessory minerals from the Bushveld Complex." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/60201.

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Zircon and other U-Th-Pb-bearing minerals are now recognized as key geochemical and geochronological tracers of the evolution of late-stage fractionated interstitial melt in mafic layered intrusions. Two separate, yet complementary, applications of laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) on zircon from layered intrusions are presented with the goals of advancing the analytical capabilities of LA-ICP-MS and showcasing the powerful geochemical fingerprinting of zircon. The effects of downhole fractionation, the time-dependent evolution of Pb-U ratios during laser ablation, represents a significant limitation on the accuracy of U-Th-Pb zircon geochronology by LA-ICP-MS. Exponential downhole correction models developed from the analyses of three common zircon reference materials (Plešovice, Temora-2, 91500) and applied to low-U zircon from Precambrian mafic intrusions (Laramie, Bushveld, Stillwater) indicate that successful correction requires careful matrix-matching the reference zircon to the unknowns. Pre-treatment protocols, including annealing and leaching, applied to all analyzed zircon produces strong effects on downhole fractionation with correlative impact on the relative accuracy of the calculated ages as a function of the downhole behaviour in the reference material used. In the Paleoproterozoic Bushveld Complex, the world’s largest layered intrusion, the trace element systematics of zircon provide temperature-composition constraints on the near-solidus crystallization of mafic-ultramafic cumulates and overlying granitic rocks. Zircon occurs with other late-stage interstitial minerals (e.g., quartz, biotite, Na-plagioclase) and crystallized at temperatures ranging from 950°C down to 690°C based on Ti-in-zircon thermometry. Forward modeling using rhyolite-MELTS of proposed Bushveld parental magmas yields similar zircon saturation temperatures from melts of intermediate-silicic composition, representing less than ~15% remaining melt, and reproduces the observed mineral assemblages. Anomalously high and variable Th/U in zircon from the Critical Zone (e.g., UG2 chromitite, Merensky Reef) reflects U loss to late, oxidized Cl-rich fluids that exsolved from the fractionated interstitial melt, a process that may be a characteristic feature of large open-system layered intrusions (e.g., Neoarchean Stillwater Complex). The presence of late-stage interstitial zircon and other accessory minerals in layered intrusions provides new in situ geochemical and geochronological tools for evaluating the origin and evolution of mafic-ultramafic magmatism in the Earth’s crust throughout geological time.
Science, Faculty of
Earth, Ocean and Atmospheric Sciences, Department of
Graduate

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45

Zahaby, Mohamed El. "Contribution à la définition d'une norme des sites pollués : élaboration d'une méthodologie pour l'évaluation de la contamination d'un sol par éléments tracés." Vandoeuvre-les-Nancy, INPL, 1998. http://www.theses.fr/1998INPL045N.

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Des études récentes ont montré l'accumulation continue des éléments tracés dans les sols, provoquant des atteintes pour l'environnement et présentant même des dangers pour la santé humaine. De ce fait, apparait aujourd'hui la nécessite d'avoir une nouvelle politique qui peut mettre en place dans un cadre réglementaire et juridique les moyens de protection des milieux naturels. Ce travail de thèse a été effectué dans le but d'établir, au moyen de méthodes statistiques et géostatistiques, un outil de diagnostic et d'évaluation de la qualité du sol et d'apprécier les risques correspondants, afin de contribuer à la détermination de valeurs guides pour les sols français. Dans un premier temps, après avoir rappelé les différents aspects normatifs en Europe et aux USA, ainsi que l'état actuel en France, nous nous attachons à présenter, de façon exhaustive, la répartition des éléments traces dans les différents types de roches et de sols. Vient ensuite une présentation de leur répartition dans les sols au niveau national, dont nous montrons que l'analyse statistique peut permettre d'interpréter au mieux la dynamique et les sources naturelles ou dues à des activités humaines des éléments traces induits dans un sol. Nous mettons notamment l'accent sur la comparaison des teneurs en éléments traces dans les sols français avec les valeurs communément adoptées comme normes ou valeurs guides par les différents pays. Dans un second temps, quatre niveaux de la distribution d'un élément trace dans un sol ont été défini : la concentration de base, le fond géochimique, la contamination et la pollution. Basé sur cette constatation, une méthode a été développée par la suite, avec, pour objectif de différencier le fond géochimique. Un jeu de données de 12 feuilles, 14000 échantillons dans les régions des Vosges et d'Alsace a été fourni par le BRGM afin de mettre au point et de valider les résultats. Enfin, la distribution spatiale des éléments tracés a été modélisée par des méthodes géostatistiques. Une estimation par la méthode de krigeage de probabilité a eu pour objectif la délimitation de la zone de pollution et l'établissement de cartes de risques face à un usage précis du sol.

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46

Moulahoum, Omar. "Dualité du magmatisme d'âge pan-africain : Aspects structuraux et pétrologiques des granites subalcalins et alumineux de la région de Tamanrasset (Hoggar central, Algérie." Nancy 1, 1988. http://www.theses.fr/1988NAN10049.

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Durant l'orogène du "Pan-Africain" (~ 600 Ma), la région du Hoggar central, à l'instar de l'ensemble du Bouclier Touareg, a été intensément affectée. Cet évènement est accompagné de la mise en place d'ensembles magmatiques variés. Dans la région de Tamanrasset, deux magmatismes de nature différente sont mis en évidence : magmatisme subalcalin et magmatisme alumineux. Le premier est représenté par les massifs syn à tardi-orogéniques (Anfeg - Tifferkit), voire post-orogénique (Aheleheg') tandis que le second est exclusivement constitué par les plutons post-orogéniques (In-Tounine et intrusions granitiques à albite-topaze). Compte tenu des critères de terrain, pétrographiques, géochimiques et parfois isotopiques, trois groupes magmatiques peuvent être distingués.

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47

Tang, Eng Hoo Joseph. "The Petrogenesis Of The Station Creek Igneous Complex And Associated Volcanics, Northern New England Orogen." Thesis, Queensland University of Technology, 2004. https://eprints.qut.edu.au/15902/1/Joseph_Tang_Thesis.pdf.

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The Station Creek Igneous Complex (SCIC) is one of the largest Middle-Late Triassic plutonic bodies in the northern New England Orogen of Eastern Australia. The igneous complex comprises of five plutons - the Woonga Granodiorite (237 Ma), Woolooga Granodiorite (234 Ma), Rush Creek Granodiorites (231 Ma) and Gibraltar Quartz Monzodiorite and Mount Mucki Diorite (227 Ma respectively), emplaced as high-level or epizonal bodies within the Devonian-Carboniferous subduction complex that resulted from a westward subduction along the east Australian margin. Composition of the SCIC ranges from monzogabbro to monzogranite, and includes diorite, monzodiorite, quartz monzodiorite and granodiorite. The SCIC has the typical I-type granitoid mineralogy, geochemistry and isotopic compositions. Its geochemistry is characteristics of continental arc magma, and has a depleted-upper mantle signature with up to 14 wt% supracrustal components (87Sr/86Srinitial = 0.70312 to 0.70391; Nd = +1.35 to +4.9; high CaO, Sr, MgO; and low Ni, Cr, Ba, Rb, Zr, Nb, Ga and Y). The SCIC (SiO2 47%-76%) has similar Nd and Sr isotopic values to island-arc and continentalised island-arc basalts, which suggests major involvement of upper mantle sourced melts in its petrogenesis. SCIC comprises of two geochemical groups - the Woolooga-Rush Greek Granodiorite group (W-RC) and the Mount Mucki Diorite-Gibraltar Quartz Monzodiorite group (MMD-GQM). The W-RC Group is high-potassium, calc-alkalic and metaluminous, whereas the MMD-GQM Group is medium to high potassium, transitional calc-alkalic to tholeiitic and metaluminous. The two geochemical groups of the SCIC magmas are generated from at least two distinct sources - an isotopically evolved Neoproterozoic mantle-derived source with greater supracrustal component (10-14 wt%), and an isotopically primitive mafic source with upper mantle affinity. Petrogenetic modeling using both major and trace elements established that the variations within respective geochemical group resulted from fractional crystallisation of clinopyroxene, amphibole and plagioclase from mafic magma, and late fractionation of alkalic and albitic plagioclase in the more evolved magma. Volcanic rocks associated with SCIC are the North Arm Volcanics (232 Ma), and the Neara Volcanics (241-242 Ma) of the Toogoolawah Group. The major and trace element geochemistry of the North Arm Volcanics is similar to the SCIC, suggesting possible co-magmatic relationship between the SCIC and the volcanic rock. The age of the North Arm Volcanics matches the age of the fractionated Rush Creek Granodiorite, and xenoliths of the pluton are found within epiclastic flows of the volcanic unit. The Neara Volcanics (87Sr/86Sr= 0.70152-0.70330, 143Nd/144Nd = 0.51253-0.51259) differs isotopically from the SCIC, indicating a source region within the HIMU mantle reservoir (commonly associated with contaminated upper mantle by altered oceanic crust). The Neara Volcanics is not co-magmatic to the SCIC and is derived from partial melting upper-mantle with additional components from the subducting oceanic plate. The high levels emplacement of an isotopically primitive mantle-derived magma of the SCIC suggest periods of extension during the waning stage of convergence associated with the Hunter Bowen Orogeny in the northern New England Orogen. The geochemical change between 237 to 227 Ma from a depleted-mantle source with diminishing crustal components, to depleted-mantle fractionate, reflects a fundamental change in the source region that can be related to the tectonic styles. The decreasing amount of supracrustal component suggests either thinning of the subduction complex due to crustal attenuation, leading to the late Triassic extension that enables mantle melts to reach subcrustal levels.

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48

Tang, Eng Hoo Joseph. "The Petrogenesis Of The Station Creek Igneous Complex And Associated Volcanics, Northern New England Orogen." Queensland University of Technology, 2004. http://eprints.qut.edu.au/15902/.

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The Station Creek Igneous Complex (SCIC) is one of the largest Middle-Late Triassic plutonic bodies in the northern New England Orogen of Eastern Australia. The igneous complex comprises of five plutons - the Woonga Granodiorite (237 Ma), Woolooga Granodiorite (234 Ma), Rush Creek Granodiorites (231 Ma) and Gibraltar Quartz Monzodiorite and Mount Mucki Diorite (227 Ma respectively), emplaced as high-level or epizonal bodies within the Devonian-Carboniferous subduction complex that resulted from a westward subduction along the east Australian margin. Composition of the SCIC ranges from monzogabbro to monzogranite, and includes diorite, monzodiorite, quartz monzodiorite and granodiorite. The SCIC has the typical I-type granitoid mineralogy, geochemistry and isotopic compositions. Its geochemistry is characteristics of continental arc magma, and has a depleted-upper mantle signature with up to 14 wt% supracrustal components (87Sr/86Srinitial = 0.70312 to 0.70391; Nd = +1.35 to +4.9; high CaO, Sr, MgO; and low Ni, Cr, Ba, Rb, Zr, Nb, Ga and Y). The SCIC (SiO2 47%-76%) has similar Nd and Sr isotopic values to island-arc and continentalised island-arc basalts, which suggests major involvement of upper mantle sourced melts in its petrogenesis. SCIC comprises of two geochemical groups - the Woolooga-Rush Greek Granodiorite group (W-RC) and the Mount Mucki Diorite-Gibraltar Quartz Monzodiorite group (MMD-GQM). The W-RC Group is high-potassium, calc-alkalic and metaluminous, whereas the MMD-GQM Group is medium to high potassium, transitional calc-alkalic to tholeiitic and metaluminous. The two geochemical groups of the SCIC magmas are generated from at least two distinct sources - an isotopically evolved Neoproterozoic mantle-derived source with greater supracrustal component (10-14 wt%), and an isotopically primitive mafic source with upper mantle affinity. Petrogenetic modeling using both major and trace elements established that the variations within respective geochemical group resulted from fractional crystallisation of clinopyroxene, amphibole and plagioclase from mafic magma, and late fractionation of alkalic and albitic plagioclase in the more evolved magma. Volcanic rocks associated with SCIC are the North Arm Volcanics (232 Ma), and the Neara Volcanics (241-242 Ma) of the Toogoolawah Group. The major and trace element geochemistry of the North Arm Volcanics is similar to the SCIC, suggesting possible co-magmatic relationship between the SCIC and the volcanic rock. The age of the North Arm Volcanics matches the age of the fractionated Rush Creek Granodiorite, and xenoliths of the pluton are found within epiclastic flows of the volcanic unit. The Neara Volcanics (87Sr/86Sr= 0.70152-0.70330, 143Nd/144Nd = 0.51253-0.51259) differs isotopically from the SCIC, indicating a source region within the HIMU mantle reservoir (commonly associated with contaminated upper mantle by altered oceanic crust). The Neara Volcanics is not co-magmatic to the SCIC and is derived from partial melting upper-mantle with additional components from the subducting oceanic plate. The high levels emplacement of an isotopically primitive mantle-derived magma of the SCIC suggest periods of extension during the waning stage of convergence associated with the Hunter Bowen Orogeny in the northern New England Orogen. The geochemical change between 237 to 227 Ma from a depleted-mantle source with diminishing crustal components, to depleted-mantle fractionate, reflects a fundamental change in the source region that can be related to the tectonic styles. The decreasing amount of supracrustal component suggests either thinning of the subduction complex due to crustal attenuation, leading to the late Triassic extension that enables mantle melts to reach subcrustal levels.

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49

VILA, GUSTAVO B. "Caracterização de silicatos e carbonatos de cálcio aplicados à dosimetria de doses altas." reponame:Repositório Institucional do IPEN, 2012. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10201.

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Made available in DSpace on 2014-10-09T12:35:56Z (GMT). No. of bitstreams: 0
Made available in DSpace on 2014-10-09T13:59:32Z (GMT). No. of bitstreams: 0
Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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50

Al-Amer, Saleh Suliaman. "Nutritional and toxicological studies on New Zealand mutton bird meat (Puffinus griseus)." Lincoln University, 2009. http://hdl.handle.net/10182/1659.

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New Zealand mutton bird or tītī (Puffinus griseus and order procellariiformes) nest in New Zealand during the summer months, migrate to the northern hemisphere during May and return in September. Their eggs are laid during November and December and the chicks are hatched in the following January and February. Large numbers of them are harvested from April to May in New Zealand. They are wild seabirds annually harvested by Maori according to the customary rights agreement set by Treaty of Waitangi.NZ mutton birds also called Sooty Shearwaters are noted for their high proportion of body fat.These birds are interesting since its sole diet is based on krill and other small marine organisms that are potentially rich in n-3 fatty acids and other marine bioactive compounds. The proximate composition, fatty and amino acids and cholesterol content of mutton bird pectoral muscle were determined and compared with other common meat to explore the nutritional value of this New Zealand delicacy. The concentration of twenty two essential and toxic elements including silver (Ag), aluminium (Al), arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), manganese (Mn), lead (Pb), selenium (Se), potassium (K), calcium (Ca), magnesium (Mg), boron (B), iron (Fe), nickel (Ni), sulphur (S), sodium (Na) and cobalt (Co) and zinc (Zn) in mutton bird breast meat (Puffinus griseus) were measured over two years to evaluate its safety for human consumption. Persistent organochlorine, dichlorodiphenyltrichloroethane (DDT) and their metabolites, and aldrin and lindane were also measured.Twenty bird carcasses were purchased in both 2006 and 2007 from a local source. Meat samples from the pectoral muscle of two carcasses were pooled to generate 10 samples for each year. These were used for trace element analysis using inductively coupled plasma-mass spectrometry (ICP-MS). Trace elements were in the range of 0 to 1.09 mg/kg wet weight for Ag, 0 to 3.32 for Al, 0.17 to 0.79 for As, 0.01 to 0.07 for Cd, 0.03 to 0.15 for Cr, 3.56 to 4.88 for Cu, 0 to 0.15 for Hg, 0.22 to 0.50 for Mn, 0 to 0.09 for Pb, 0.66 to 1.18 for Se and 11.49 to 23.70 for Zn. In 2006, Ag, Al, Mn and Zn concentrations were significantly higher but Pb and Hg concentrations significantly lower compared to the 2007 samples (P < 0.05). Apart from one sample in 2006, all the samples were below the published maximum level for concern. However, our preliminary data indicated that the higher level of Cd and other metals in the skin of mutton bird may compromise the overall safety to humans consuming the skin of mutton birds. It is suggested that the evaluation of the metals in different parts and/or the whole mutton bird at different seasons is required to assure complete safety to the consumers.Furthermore, the nutritional value of mutton bird meat was studied over two harvesting seasons (2006 and 2007) to investigate the impact of seasonal variation. The moisture and carbohydrates contents ranged between 54.0 to 55.0 % and 2.8 to 3.0 %, respectively, and no seasonal effects were evident in these components. The values for fat and ash contents were higher and the protein content lower for birds harvested in 2007 compared with the 2006 values which ranged from 11.8 to 13.0, 10.3 to 11.7, and 20.3 to 18.5 % for fat, ash and protein content respectively. The major amino acids in mutton bird pectoral muscle were glutamate, aspartate, lysine, leucine, and arginine. Higher lysine concentrations and lower proline, cystein and methionine were found in mutton birds compared with the literature values for beef, lamb and pork. The essential amino acid content in mutton bird (43.8 and 44.9 % in 2006 and 2007, respectively) was slightly higher than those found in beef and lamb meats (42-43%).The major fatty acids detected were palmitic (C16:0), stearic (C18:0), oleic and isomers (C18:1), eicosenoic (C20:1), Docosahexaenoic acid (DHA) (C22:6), icosapentaenoic acid (EPA) (C 20:5) and these accounted for approximately 77% of the fatty acids. The 3/6 ratio of fats from pectoral muscle was 1.3. The cholesterol concentration varied slightly in the two years with 184.4±37.37and 134.4±25.55mg/100 g fresh weight for 2007 and 2008 respectively. Mutton bird was shown to contain significantly higher cholesterol content (134.4-184.4) than other common meat such as chicken (80.3-88.9), lamb (62.3), fish (52.79) and beef (51.97). Overall, the nutritional value of mutton bird muscle was similar to or superior to the traditionally protein sources such as seafood and red meat. Annual variations existed in the composition of Mutton bird pectoral muscle but this is not of nutritional consequence but might be a useful indicator for ecological events such as feed availability and other environmental issues. Mutton bird seems to be a good source of essential minerals, Zn and Fe compared with other traditional meats source. Mutton bird meat is nutritionally as good as the major sources of red or white meats. It may even have advantages over the other common meats (beef, lamb, fish and chicken) due to its high protein and monounsaturated fatty acids (omega n-3 and n-6) content. However, its high cholesterol content may represent a risk factor for some people.

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