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Constraining Metamorphic and Tectonic Evolution in Convergent Terranes: How Trace Elements and Mineral Inclusions Shape Mechanical and Reconstructive ModelsAshley, Kyle T. 01 June 2015 (has links)
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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Mechanistic understanding of biogeochemical transformations of trace elements in contaminated minewaste materials under reduced conditionsKarna, Ranju Rani January 1900 (has links)
Doctor of Philosophy / Department of Agronomy / Ganga M. Hettiarachchi / The milling and mining operations of metal ores are one of the major sources of heavy metal contamination at earth’s surface. Due to historic mining activities conducted in the Tri-State mining district, large area of land covered with mine waste, and soils enriched with lead (Pb), zinc (Zn) and cadmium (Cd) remain void of vegetation influencing ecosystem and human health. It has been hypothesized that if these minewaste materials are disposed of in the flooded subsidence pits; metals can be transformed into their sulfide forms under reduced conditions limiting their mobility, and toxicity. These mine waste materials are high in pH, low in organic carbon (OC) and sulfur (S). The objective of this study was to examine the effect of OC and S addition on the biogeochemical transformations of Pb, Zn and Cd in submerged mine waste containing microcosms. Advanced molecular spectroscopic and microbiological techniques were used to obtain a detail, mechanistic, and molecular scale understanding of the effect of natural and stimulated redox conditions on biogeochemical transformation and dynamics of Pb, Zn and Cd essential for designing effective remediation and mitigation strategies.
The results obtained from these column studies indicated that Pb, Zn and Cd were effectively immobilized upon medium (119-day) and long-term (252-day) submergence regardless of treatment. The OC plus S treatment enhanced sulfide formation as supported by scanning electron microscopy- energy dispersive X-ray technique, and synchrotron based bulk-, and micro-X-ray fluorescence and absorption spectroscopy analyses. Microbial community structure changed with OC and S addition with the enhancement sulfur reducing bacteria genes (dsrA/B), and decreased metal resistance genes over time. The long-term submergence of existing mine tailings with OC plus S addition reduced trace metals mobility most likely through dissimilatory sulfate reduction under stimulated reduced conditions. Colloidal assisted metal transportation (<1% of both Pb and Cd) occurred during initial submergence. Retention filters are suggested to avoid colloidal metal transport in order to meet the maximum concentration limit for Pb and Cd in surface and groundwater.
This research enhances our understanding of the redox processes associated with the sequestration of non-redox sensitive metals through dissimilatory reduction of sulfates in mine waste materials and/or waste water and provides regulators with useful scientific evidence for optimizing remediation goals.
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A study of obsidian in prehistoric central and Eastern Europe, and it's trace element characterization : an analytically-based study of archaeological obsidian in Central and Eastern Europe, an investigation of obsidian sources in this area, and the characterization of these obsidians using neutron activation analysisThorpe, Olwen Williams January 1978 (has links)
Fieldwork in the Zemplen Mountain area of north-eastern Hungary showed that there are at least eight geological sources of obsidian here, five of which have obsidian of a workable quality. There are a further three sources in the Slovak Zemplen, all of which provide workable obsidian. Sources in Central Slovakia are highly devitrified and not useable, and reported sources in Rumania had been discounted earlier (Nandris, 1975). Forty-six samples of obsidian from the Zemplen sources, and 293 pieces from 87 archaeological sites in Central and Eastern Europe, were analysed by neutron activation analysis for 15 trace and two major elements. The trace elements used included those which are geochemically likely to show the greatest variation between different obsidian sources, and which are not badly affected by devitrification and hydration of the obsidian, for example the rare earth elements. The analytical data was processed using Cluster Analysis. 242 of the archaeological samples came from Slovak sources, 22 from Hungarian sources, 9 from Lipari and 5 from Melos. In addition, 6 samples were tentatively assigned to Carpathian sources, and 9 could not be assigned to any source. Obsidian from the Zemplen Mountains was distributed up to a distance of approximately 480 km from the sources; it was used extensively in Slovakia and Hungary and reached southern Poland, Austria, Moravia, central Yugoslavia, north-east Italy and central Rumania. Obsidian use in central and eastern Europe began in the Mousterian period. The earliest pieces analysed were Aurignacian and came from Hungarian sources. Later, in the Gravettian, Slovakian sources began to be exploited and remained predominant until obsidian use declined sharply in the Later Neolithic, and Copper and Bronze Ages. The Carpathian obsidian distribution overlaps with the Liparian distribution at one site in north-east Italy. There is no evidence for an overlap with Aegean or Near Eastern sources. The rate of fall off of obsidian away from the sources suggests a down-the-line trading mechanism.
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Etude de la dynamique, des sources et de la spéciation des éléments tracés dans le bassin versant de l’orge (Essonne, France) / Dynamics, sources and speciation of trace elemetns in the Orge River watershed (Essonne, France)Le pape, Pierre 04 December 2012 (has links)
Ce travail a pour but d’étudier la dynamique des éléments traces (ETs) dans la colonne d’eau d’une rivière anthropisée : l’Orge. La partie amont du bassin versant draine en majorité des terrains boisés et des terres agricoles, et vers l’aval, des zones urbanisées de plus en plus denses jusqu’à son exutoire dans la Seine, au sud de Paris. Quatre campagnes de prélèvements ont été effectuées le long de l’Orge suivant une année hydrologique (2010/2011). Le suivi spatio-temporel des concentrations dans la phase dissoute (< 0,45 µm) et dans les matières en suspension (MES) a été associé à des outils de traçage isotopique (δ34S [SO42-], 206Pb/207Pb) pour comprendre la dynamique de la partition des ETs ainsi que pour caractériser leurs sources en rivière sous pression urbaine. Une caractérisation fine de la spéciation solide du zinc, contaminant inorganique majeur en rivière dans ce bassin versant a été effectuée en couplant diffraction des rayons X, microscopie électronique à balayage et à transmission associée à la microanalyse, et spectroscopie d’absorption des rayons X sous rayonnement synchrotron. Les résultats géochimiques caractérisent les rejets de ruissellement et les rejets liés à l’assainissement comme des sources majeures d’ETs en rivière. Les résultats des analyses isotopiques ont permis de créer un indicateur de la pression anthropique en rivière, traçant à la fois les compartiments dissous et particulaire, tout en tenant compte des paramètres physico-chimiques des eaux et de l’hydrodynamisme. L’analyse de la spéciation solide du zinc dans les MES a permis d’identifier les phases porteuses principales de cet élément comme étant les oxyhydroxydes de fer et manganèse à composante phosphatée, la calcite, les phases argileuses et la silice amorphe. La microscopie confirme l’existence de ces phases ainsi que l’existence de phases porteuses accessoires dans la colonne d’eau oxygénée, notamment des sulfures. Plus généralement, l’ensemble de ces investigations a permis de mieux comprendre le fonctionnement des cycles biogéochimiques des ETs en rivière urbanisée, et offre de nouvelles perspectives de recherche encore largement sous exploitées grâce à l’analyse conjointe de la spéciation et de l’isotopie des métaux. / The aim of this work is to study the dynamics of trace elements (TE) in the water column of the Orge River. In the upstream part of the watershed, land uses consist mainly in forests and agricultural soils, whereas downstream, the population density reaches up to 8,000 inh. km-2, in the suburbs of Paris Megacity. The sampling sites were chosen to describe a gradation in urbanization influence from up to downstream in this particularly contrasted catchment. Four sampling campaigns were performed at seven selected sites along the Orge River during an hydrological year (2010/2011). The spatio-temporal monitoring of the concentrations in the dissolved phase (< 0.45 µm) and in suspended particulate matter (SPM) was associated to isotopic tools (δ34S [SO42-], 206Pb/207Pb) to understand both the dynamics of TE partition and the sources of contamination. Speciation of zinc was investigated as it is the main inorganic contaminant in the Orge River catchment, using X-ray diffraction, scanning/transmission electron microscopy coupled to microanalysis, and synchrotron X-ray spectroscopy. Results of geochemical analyses showed that runoff and sewer releases are major sources of contamination in river. Results from isotopic measurements allow to build a hydro-geochemical indicator of anthropogenic pressure in river which considers both physico-chemistry and hydrodynamics, by tracing simultaneously dissolved and particulate compartments. The investigation of zinc speciation permits to identify iron and manganese oxyhydroxydes, calcite, clays and amorphous silica as main bearing phases for this element. Microscopy results confirmed the existence of such phases in river and allowed the identification of secondary zinc bearing phases as sulfides, “surprisingly” present in the oxic water column. At last, this work permitted a better understanding of biogeochemical cycling of TE in urbanized rivers, and to explore new research schemes by coupling speciation and isotopic measurements for specific elements.
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Accumulation et translocation de cinq éléments traces dans la biomasse aérienne de végétaux d’intérêt dans un contexte de phytoremédiationLapierre, Esther 05 1900 (has links)
No description available.
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Interactions between aqueous fluids and silicate melts : equilibration, partitioning and complexation of trace elementsBorchert, Manuela January 2010 (has links)
The origin and evolution of granites has been widely studied because granitoid rocks constitute a major portion of the Earth ́s crust. The formation of granitic magma is, besides temperature mainly triggered by the water content of these rocks. The presence of water in magmas plays an important role due to the ability of aqueous fluids to change the chemical composition of the magma. The exsolution of aqueous fluids from melts is closely linked to a fractionation of elements between the two phases. Then, aqueous fluids migrate to shallower parts of the Earth ́s crust because of it ́s lower density compared to that of melts and adjacent rocks. This process separates fluids and melts, and furthermore, during the ascent, aqueous fluids can react with the adjacent rocks and alter their chemical signature. This is particularly impor- tant during the formation of magmatic-hydrothermal ore deposits or in the late stages of the evolution of magmatic complexes. For a deeper insight to these processes, it is essential to improve our knowledge on element behavior in such systems. In particular, trace elements are used for these studies and petrogenetic interpretations because, unlike major elements, they are not essential for the stability of the phases involved and often reflect magmatic processes with less ambiguity. However, for the majority of important trace elements, the dependence of the geochemical behavior on temperature, pressure, and in particular on the composition of the system are only incompletely or not at all experimentally studied. Former studies often fo- cus on the determination of fluid−melt partition coefficients (Df/m=cfluid/cmelt) of economically interesting elements, e.g., Mo, Sn, Cu, and there are some partitioning data available for ele- ments that are also commonly used for petrological interpretations. At present, no systematic experimental data on trace element behavior in fluid−melt systems as function of pressure, temperature, and chemical composition are available. Additionally, almost all existing data are based on the analysis of quenched phases. This results in substantial uncertainties, particularly for the quenched aqueous fluid because trace element concentrations may change upon cooling. The objective of this PhD thesis consisted in the study of fluid−melt partition coefficients between aqueous solutions and granitic melts for different trace elements (Rb, Sr, Ba, La, Y, and Yb) as a function of temperature, pressure, salinity of the fluid, composition of the melt, and experimental and analytical approach. The latter included the refinement of an existing method to measure trace element concentrations in fluids equilibrated with silicate melts di- rectly at elevated pressures and temperatures using a hydrothermal diamond-anvil cell and synchrotron radiation X-ray fluorescence microanalysis. The application of this in-situ method enables to avoid the main source of error in data from quench experiments, i.e., trace element concentration in the fluid. A comparison of the in-situ results to data of conventional quench experiments allows a critical evaluation of quench data from this study and literature data.
In detail, starting materials consisted of a suite of trace element doped haplogranitic glasses with ASI varying between 0.8 and 1.4 and H2O or a chloridic solution with m NaCl/KCl=1 and different salinities (1.16 to 3.56 m (NaCl+KCl)). Experiments were performed at 750 to 950◦C and 0.2 or 0.5 GPa using conventional quench devices (externally and internally heated pressure vessels) with different quench rates, and at 750◦C and 0.2 to 1.4 GPa with in-situ analysis of the trace element concentration in the fluids. The fluid−melt partitioning data of all studied trace elements show
1. a preference for the melt (Df/m < 1) at all studied conditions,
2. one to two orders of magnitude higher Df/m using chloridic solutions compared to experiments with H2O,
3. a clear dependence on the melt composition for fluid−melt partitioning of Sr, Ba, La, Y, and Yb in experiments using chloridic solutions,
4. quench rate−related differences of fluid−melt partition coefficients of Rb and Sr, and
5. distinctly higher fluid−melt partitioning data obtained from in-situ experiments than from
comparable quench runs, particularly in the case of H2O as starting solution.
The data point to a preference of all studied trace elements for the melt even at fairly high salinities, which contrasts with other experimental studies, but is supported by data from studies of natural co-genetically trapped fluid and melt inclusions. The in-situ measurements of trace element concentrations in the fluid verify that aqueous fluids will change their composition upon cooling, which is in particular important for Cl free systems. The distinct differences of the in-situ results to quench data of this study as well as to data from the literature signify the im- portance of a careful fluid sampling and analysis. Therefore, the direct measurement of trace element contents in fluids equilibrated with silicate melts at elevated PT conditions represents an important development to obtain more reliable fluid−melt partition coefficients. For further improvement, both the aqueous fluid and the silicate melt need to be analyzed in-situ because partitioning data that are based on the direct measurement of the trace element content in the fluid and analysis of a quenched melt are still not completely free of quench effects.
At present, all available data on element complexation in aqueous fluids in equilibrium with silicate melts at high PT are indirectly derived from partitioning data, which involves in these experiments assumptions on the species present in the fluid. However, the activities of chemical components in these partitioning experiments are not well constrained, which is required for the definition of exchange equilibria between melt and fluid species. For example, the melt-dependent variation of partition coefficient observed for Sr imply that this element can not only be complexed by Cl− as suggested previously. The data indicate a more complicated complexation of Sr in the aqueous fluid. To verify this hypothesis, the in-situ setup was also used to determine strontium complexation in fluids equilibrated with silicate melts at desired PT conditions by the application of X-ray absorption near edge structure (XANES) spectroscopy. First results show a strong effect of both fluid and melt composition on the resulting XANES spectra, which indicates different complexation environments for Sr. / Die Entstehung und Entwicklung von Graniten steht seit Jahrzehnten im Fokus vieler geologischer Studien, da sich die Erdkruste zu großen Teilen aus granitoiden Gesteinen zusammensetzt. Von besonderer Bedeutung für die Bildung von granitischen Schmelzen ist neben der Temperatur, der Wassergehalt der Schmelze, da dieser Parameter die chemische Zusammensetzung der Schmelze entscheidend verändern kann. Die Entmischung wässriger Fluide aus Schmelzen führt zur Neuverteilung von Elementen zwischen diesen Phasen. Bedingt durch die geringere Dichte des wässrigen Fluids im Vergleich zur Schmelze und dem Nebengestein, beginnt dieses aus tieferen Erdschichten aufzusteigen. Damit verknüpft ist nicht nur eine räumliche Trennung von Schmelze und Fluid, sondern auch die Alterierung des Nebengestein. Dieser Prozess ist insbesondere bei der Bildung von magmatisch-hydrothermalen Lagerstätten und in späten Entwicklungsstadien magmatischer Komplexe wichtig. Für ein detailliertes Verständnis dieser Prozesse ist es notwendig, das Elementverhalten in solchen Systemen in Abhängigkeit von Parametern wie Temperatur, Druck und chemischer Zusammensetzung des Systems experimentell zu untersuchen, und Elementverteilungskoeffizienten als Funktion dieser Variablen zu bestimmen. Für die Untersuchungen sind insbesondere Spurenelemente geeignet, da diese im Gegensatz zu Hauptelementen nicht essentiell für die Stabilität weiterer auftretender Phasen sind, aber sehr sensibel auf Änderungen intensiver Variablen reagieren können. Zudem werden bei geochemischen Mineral- und Gesteinsanalysen viele Spurenelemente, Spurenelementverhältnisse, und Spurenelementisotope als petrogenetische Indikatoren verwendet, d.h. diese Daten liefern Informationen darüber, wann und in welcher Tiefe und bei welchen chemischen Bedingungen ein Gestein gebildet worden ist, und welche weiteren Prozesse es auf dem Weg zur Erdoberfläche durchlaufen hat. Allerdings sind für vie- le Spurenelemente die Abhängigkeiten der Verteilung zwischen Fluiden und Schmelzen von intensiven Variablen nicht, oder nur unzureichend experimentell untersucht worden. Zusätzlich dazu basiert die Mehrheit der experimentell gewonnenen Verteilungskoeffizienten und deren Interpretation, insbesondere hinsichtlich der Elementkomplexierung im Fluid, auf der Analyse von schnell abgekühlten Phasen. Bisher ist nicht geklärt, ob solche Analysen repräsentativ sind für die Zusammensetzungen der Phasen bei hohen Drücken und Temperaturen.
Das Ziel dieser Studie war die Erarbeitung eines experimentellen Datensatzes zur Spu- renelementverteilung zwischen granitischen Schmelzen und wässrigen Fluiden in Abhängigkeit von der Schmelzzusammensetzung, der Salinität des Fluids, des Drucks und der Temperatur. Ein Hauptanliegen der Arbeit bestand in der Weiterentwicklung einer experimentellen Methode bei welcher der Spurenelementgehalt im Fluid in-situ, d.h. unter hohen Drücken und Temperaturen, und im Gleichgewicht mit einer silikatischen Schmelze bestimmt wird. Die so gewonnenen Daten können anschließend mit den Resultaten von Abkühlexperimenten vergli- chen werden, um diese und auch Literaturdaten kritisch zu bewerten. Die Daten aller unter- suchten Spurenelemente dieser Arbeit (Rb, Sr, Ba, La, Y und Yb) zeigen:
1. unter den untersuchten Bedingungen eine Präferenz für die Schmelze unabhängig von der chemischen Zusammensetzung von Schmelze und Fluid, Druck oder Temperatur,
2. die Verwendung von chloridhaltigen Fluiden kann die Verteilungskoeffizienten um 1 bis 2 Größenordnungen anheben und
3. für die Verteilungskoeffizienten von Sr, Ba, La, Y und Yb eine starke Abhängigkeit von der Schmelzzusammensetzung im chloridischen System.
Der Vergleich der Daten der verschiedenen Methoden zeigt, dass insbesondere für chloridfreie Fluide große Diskrepanzen zwischen den in-situ Daten und Analysen von abgeschreckten Proben bestehen. Dieses Ergebnis beweist eindeutig, dass beim Abschrecken der Proben Rückreaktionen stattfinden, und dass Daten, welche auf Analysen abgeschreckter Fluide basieren, nur eingeschränkt verwendet werden sollten. Die Variation der Verteilungskoeffizienten von Sr, Ba, La, Yb, und Y als Funktion der Schmelzzusammensetzung ist entweder auf eine Änderung der Komplexierung im Fluid und/oder einen anderen veränderten Einbau dieser Elemente in die Schmelze zurückzuführen. Daher wurde im Rahmen dieser Arbeit erstmals versucht, die Elementkomplexierung in silikatischen Fluiden direkt bei hohen Temperaturen und Drücken zu bestimmen. Die Daten für Sr zeigen, dass abhängig von der Schmelzzusammensetzung unterschiedliche Komplexe stabil sein müssen.
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Bioindicadores para determinação de metais pesados no Reservatório da Itaipu Binacional, Paraná, Brasil / Bioindicators for the determination of heavy metals in the reservoir of Itaipu, Paraná, BrazilChambo, Ana Paula Sartório 26 August 2011 (has links)
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Previous issue date: 2011-08-26 / Fundação Araucária / This study was conducted in the reservoir of Itaipu Hydroelectric Plant, located in the western region of Paraná State, during the March/2010 to April/2009 and aimed to study the chemical composition (macronutrients, micronutrients and toxic heavy metals), the bioaccumulation of biologically essential metals, copper (Cu), iron (Fe), zinc (Zn) and manganese (Mn), and non-essential toxic heavy metals, cadmium (Cd), chromium (Cr) and lead (Pb) in tissues of the armado (P. granulosus), mollusks (L. fortunei) and aquatic plants (E. densa and E. crasssipes), beyond the study of water quality and sediment under modified atmospheres, such as reservoirs for multiple uses, during the season the year. Fifteen fish were collected monthly to determine the factor relative corporal condition (Kn), the index of viscera total (IVT), visceral fat index (IGV), the hepatosomatic index (HSI) and the metal pollution index (MPI), as well as samples the sediment, water and the biomarkers golden mussel and two species of aquatic macrophytes, E. crassipes and E. dense. It was observed that the carcass of the armado bioaccumulate in the following order Fe, Ca, Zn, Pb, Mn, K, Mg, Cr, Cu e Cd. The nitrogen was concentrated in greater proportion in the carcass (110.58 g kg-1) and fillet (109.96 g kg-1) and phosphorus in the liver (43.26 g kg-1). The Cd was present in 50% of carcass samples (1.20 mg kg-1) and skin (1.00 mg kg-1) and 100% of the samples of gills (1.00 mg kg-1). The Cr was detected in 33% of carcass samples (2.75 mg kg-1) and gills (1.00 mg kg-1) and 17% of fillet samples (2.00 mg kg-1). The presence of lead was found in 100% of samples with levels ranging from 20.17 mg kg-1 in the carcass and 7.83 mg kg-1 in the fillet. The distribution of Cu, Zn and Mn in the sediment and water did not change seasonally. The analytical method used did not detect the presence of Cu and Zn in the water sample. The physical and chemical variables of water were not oscillated along the year season. The index calculated for the E. densa responded significantly seasonal fluctuations, with the highest rates were obtained during the summer followed by spring, winter and autumn. The armado captured during the experiment were contaminated by heavy metals Cd, Cr and Pb at levels above those recommended by current legislation. The rate of metal contamination suggests that the liver is the organ most bioaccumulate heavy metals in the gun. The deposition of heavy metals in sediment and water did not change seasonally, the sampling of sediment, E. densa and root of E. crassipes may indicate the composition of environmental contamination / Este trabalho foi realizado no reservatório da Usina Hidrelétrica de Itaipu Binacional, localizada na região oeste do Estado do Paraná, durante o período de abril/2009 a março/2010 e teve como objetivo o estudo sobre a composição química (macronutrientes, micronutrientes e metais pesados tóxicos), a bioacumulação de metais pesados biologicamente essenciais, cobre (Cu), ferro (Fe), zinco (Zn) e manganês (Mn), e metais pesados tóxicos, cádmio (Cd), cromo (Cr) e chumbo (Pb), nos tecidos do armado (P. granulosus), moluscos (L. fortunei) e plantas aquáticas (E. densa e E. crasssipes), além do estudo da qualidade da água e dos sedimentos em ambientes modificados, como os reservatórios de usos múltiplos, durante as estações do ano. Foram coletados mensalmente quinze peixes para determinação do fator de condição corporal relativo, o índice de víscera total, o índice de gordura visceral, o índice hepatossomático e o índice de poluição por metais, bem como amostras de sedimento, água e dos bioindicadores mexilhão dourado e duas espécies de macrófitas aquáticas E. crassipes e E. densa. Observou-se que a carcaça do armado bioacumulou os elementos na seguinte ordem decrescente Fe, Ca, Zn, Pb, Mn, K, Mg, Cr, Cu e Cd. O nitrogênio concentrou-se em maior proporção na carcaça (110,58 g kg-1) e no filé (109,96 g kg-1) e o fósforo no fígado (43,26 g kg-1). O Cd esteve presente em 50% das amostras de carcaça (1,20 mg kg-1) e pele (1,00 mg kg-1) e em 100% das amostras de brânquias (1,00 mg kg-1). O Cr foi detectado em 33% das amostras de carcaça (2,75mg kg-1) e brânquias (1,00 mg kg-1) e em 17% das amostras de filé (2,00 mg kg-1). A presença de chumbo foi constatada em 100% das amostras com teores variando entre 20,17 mg kg-1 na carcaça e 7,83 mg kg-1 no filé. A distribuição dos metais Cu, Fe, Zn e Mn no sedimento e na água não sofreram efeito sazonal. O método analítico utilizado não detectou a presença de Cu e Zn na água do reservatório. As variáveis físicas e químicas da água não oscilaram ao longo do ano. O índice de metais pesados calculado para a E. densa respondeu significativamente as oscilações sazonais, sendo que os maiores valores obtidos durante o verão seguidos pela primavera, inverno e outono. Os armados capturados durante o período experimental estavam contaminados pelos metais pesados Cd, Cr e, Pb em níveis acima dos recomendados pela legislação vigente. O índice de contaminação por metais aponta que o fígado é o órgão que mais bioacumulou metais pesados no armado. As deposições de metais pesados no sedimento e na água não sofreram efeito sazonal. A amostragem dos sedimentos, E. densa e raiz da E. crassipes pode indicar a composição da contaminação do ambiente e a E. densa pode ser utilizado como bioindicador em áreas poluídas
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Valorization of Citrus spp. Cultivars cultivated in Sicily for the industrial use of citrus derivatives and in particular for potential alternative uses of essential oils for the enhancement of the island's citrus productionIoppolo, Antonino 17 January 2021 (has links)
[ES] En esta tesis doctoral se discuten una serie de cuestiones científicas relacionadas con a la producción y el procesamiento de algunas especies de cítricos de especial relevancia en Sicilia y en el área mediterránea. Los objetivos se centran en estudiar la trazabilidad y sostenibilidad de la producción de algunas especies de cítricos, así como encontrar nuevas aplicaciones a los subproductos y productos de desecho de la industria, con el fin de mejorar su rentabilidad. Por lo tanto, los temas que se desarrollarán serán los siguientes: caracterización de los compuestos bioactivos presentes en aceites esenciales y en el hidrolato de diferentes especies de cítricos; seguimiento del efecto del estrés hídrico controlado sobre la producción de aceites esenciales en hojas y flores del cv. Sanguinelli de Citrus sinensis y del cv. Clemenules de Citrus reticulata; estudio de los efectos fitotóxicos de los aceites esenciales en cuatro especies arvenses importantes en el área mediterránea, dos monocotiledóneas (Echinochloa crus-galli (L.) P.Beauv. y Avena fatua L.) y dos dicotiledóneas (Amaranthus retroflexus L. y Portulaca oleracea L.) mediante experimentos in vitro e in vivo; estudio del efecto bioestimulantes de las aguas residuales de la industria procesadora de cítricos sobre la comunidad microbiana del suelo; cuantificación de elementos de tierras raras en frutos de limón cultivados en diferentes áreas geográficas, para su posible uso como trazador geoquímico. Los principales resultados obtenidos son la caracterización de diferentes aceites esenciales, de los cuales los producidos por los residuos de la poda podrían ser utilizados como método de extracción de nuevos aceites esenciales con alto rendimiento. También se han encontrado sustancias nutracéuticas y farmacológicas en los hidrolatos industriales de naranja. Por otra parte, el aceite esencial industrial de limón mostró un buen potencial como agente herbicida, siendo, por tanto, de gran interés en la fabricación de herbicidas de origen natural, biodegradables y ecológicos. La aplicación del estrés hídrico controlado después del reposo invernal y, por tanto, en el momento de la brotación incrementó el diámetro final del fruto. La respuesta en el árbol no fue inmediata. La aplicación de hidrolatos de limón, naranja y mandarina al suelo junto al agua de riego, potenció los depósitos de C contribuyendo a aumentar la biomasa y mejoró la actividad microbiana. Estos resultados ponen de manifiesto el papel que los hidrolatos pueden desempeñar en la agricultura sostenible mejorando la fertilidad del suelo. Finalmente, el modelo de elementos de tierras raras podría utilizarse como una herramienta de conexión entre la producción de limón y el suelo del que proviene, contribuyendo, de esta manera, a su caracterización geográfica. En resumen, los resultados obtenidos en esta tesis contribuyen a impulsar el sector cítrico siciliano ya que: proporcionan medios para una agricultura sostenible; aumentan el valor de los subproductos y residuos de la industria; proponen aplicaciones para que el ciclo de producción y transformación sea más rentable y revalorizan los limones sicilianos vinculándolos a su zona de producción. / [CA] En esta tesi doctoral es discutixen una sèrie de qüestions científiques relacionades amb la producció i el processament d'algunes espècies de cítrics d'especial rellevància a Sicília i a l'àrea mediterrània. Els objectius, acordats prèviament amb la indústria de cítrics "EuroFood" i finançats pel projecte d'investigació "PON Industrial Ph.D. - a.a. 2016/2017", es centren en estudiar la traçabilitat i sostenibilitat de la producció d'algunes espècies de cítrics, així com de trobar noves aplicacions als subproductes i productes de rebuig de la indústria, amb el fi de millorar la seua rentabilitat. Per tant, els temes que es desenvoluparan seran els següents: caracterització dels compostos bioactius presents en els olis essencials i en el l'hidrolato de diferents espècies de cítrics; seguiment de l'efecte de l'estrés hídric controlat en la producció d'olis essencials en fulles i flors del cv. Sanguinelli de Citrus sinensis i del cv. Clemenules de Citrus reticulata; estudi dels efectes fitotòxicos dels olis essencials de cítrics en quatre espècies arvenses importants en l'àrea mediterrània, dos monocotiledònies (Echinochloa crus-galli (L.) P.Beauv. i Avena fàtua L.) i dos dicotiledònies (Amaranthus retroflexus L. i Portulaca oleracea L.) per mitjà de diferents experiments in vitro i in vivo; estudi de l'efecte bioestimulant de les aigües residuals de la indústria processadora de cítrics sobre la comunitat microbiana del sòl; quantificació d'elements de terres rares en fruits de llima cultivats en diferents àrees geogràfiques, per al seu possible ús com a traçador geoquímic. Els principals resultats obtinguts són la caracterització de diferents olis essencials, dels quals els produïts pels residus de la poda podrien ser utilitzats com a mètode d'extracció de nous olis essencials amb alt rendiment. També s'han trobat substàncies nutracéutiques i farmacològiques en els hidrolats industrials de taronja. D'altra banda, l'oli essencial industrial de llima va mostrar un bon potencial com a agent herbicida, sent, per tant, de gran interés en la fabricació d'herbicides d'origen natural, biodegradables i ecològics. L'aplicació de l'estrés hídric controlat després del repòs hivernal i, per tant, en el moment de la brotació va incrementar el diàmetre final del fruit. La resposta en l'arbre no va ser immediata. L'aplicació de hidrolats de llima, taronja i mandarina al sòl amb l'aigua de reg, va augmentar els depòsits de carbó (C) contribuint a augmentar la biomassa i va millorar l'activitat microbiana. Aquests resultats posen de manifest el paper dels hidrolats en l'agricultura sostenible millorant, d'aquesta manera, la fertilitat del sòl. Finalment, el model d'elements de terres rares podria utilitzar-se com una ferramenta d'enllaç entre la producció de llima i el sòl del què prové, contribuint, d'esta manera, a la seua caracterització geogràfica. En resum, els resultats obtinguts en esta tesi doctoral contribueixen a impulsar el sector cítric sicilià ja que: - proporcionen mitjans per a una agricultura sostenible; - augmenten el valor dels subproductes i residus de la indústria; - proposen aplicacions perquè el cicle de producció i transformació siga de més rendabilitat; - revaloritzen les llimes d'origen sicilià vinculant-les a la seua zona de producció. / [EN] In this doctoral thesis are discussed a series of scientific issues regarding citrus fruits production and processing, species of particular relevance in Sicily and in the Mediterranean area.
Objectives and research activities addressed in this thesis were agreed with the citrus industry "EuroFood" and financed by the research project "PON industrial Ph.D. - a.a. 2016/2017".
The research project was targeted to study the traceability and sustainability of citrus production, and to find new applications to the by-products and waste products of citrus industry with the objective of appreciate and enhance the Sicilian citrus industry.
The following topics are addressed and developed in this thesis:
- Characterization of the bioactive compounds present in essential oils (EOs) and in the hydrolate of different citrus species.
- Monitoring of the effect of controlled water stress on the production of EOs in leaves and flowers of Citrus sinensis (L.) Osbeck cv. 'Sanguinelli' and Citrus reticulata Blanco cv. 'Clemenules';
-Test the phytotoxic effects of citrus EOs on four important weed species in the Mediterranean area, two monocotyledon (Echinochloa crus-galli (L.) P.Beauv. and Avena fatua L.) and two dicotyledon (Amaranthus retroflexus L., and Portulaca oleraceaL.) by different experiments in vitro and in greenhouse conditions;
-Evaluation of the effect as natural biostimulants of wastewaters from citrus processing industry by its application on soil microbial community;
-Quantification of rare earth elements in lemon fruits from different geographical areas for its possible use as geochemical tracers applied to lemon production.
Different Citrus EOs have been characterized in this study and it has been verified that the oils produced by the pruning waste could be used for the extraction of EOs with high yields. In addition, nutraceutical and pharmacological substances have been found in the orange industrial hydrolates.
Industrial lemon EO showed good potential when testing its herbicidal activity. Lemon EO represents a good basis for the development of herbicides of natural origin, biodegradable and eco-friendly.
Thanks to the application of water stress after the winter vegetative restart, a conclusion found was that water stress increased the diameter of the fruit and it was observed that the effects of stress were not immediate on citrus trees, but were evident after some time.
The study of the application of lemon, orange and mandarin hydrolates in the soil, as irrigation water provided the effects on stable and labile soil C pools, on biomass and microbial activity and on main microbial groups. Overall, hydrolates can play a role in sustainable agriculture because when added to a soil, they improve soil quality and fertility.
The Rare Earth Element model could be used as a tool to connect lemon production to the soil where they were produced, for a possible geographical characterization and a direct link between the production and the territory or soil.
The results obtained were very interesting because:
- they provided the means for sustainable agriculture;
- they increased the value of the by-products and waste products of the citrus industry;
- they proposed applications for the citrus production and transformation cycle being more sustainable;
- they could valorize the Sicilian lemons by linking them to their production area.
These results could have practical repercussions in the production cycle of citrus fruits and give a boost to the Sicilian citrus fruit sector. / Objectives and research activities addressed in this thesis were agreed with the citrus industry
"EuroFood" and financed by the research project PON industrial Ph.D. - a.a. 2016/2017 / Ioppolo, A. (2020). Valorization of Citrus spp. Cultivars cultivated in Sicily for the industrial use of citrus derivatives and in particular for potential alternative uses of essential oils for the enhancement of the island's citrus production [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/159385 / TESIS
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Geochemical evidence for incremental emplacement of Palms pluton, southern CaliforniaRoell, Jennifer L. 02 February 2010 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / The objectives of this study are, generally, to analyze and understand internal processes that produce melts in an oceanic-continental subduction setting; and, specifically, to understand the assembly of a Cretaceous magmatic arc pluton (Palms pluton), including the timing of melt emplacement(s) and melt evolution from the source. SiO2 concentrations vary from ~ 69-76 % by weight. Whole rock trace element concentrations vary up to 7 times. Zircon analysis shows a minimum age difference in the pluton of 3 my, if considering the uncertainties of the oldest and youngest samples. According to the model made from the HEAT program, this is approximately six times longer than the estimated crystallization time of one batch of melt with the same physical properties as the Palms pluton. Two distinct sources, perceived from chemical analysis of premagmatic zircons, are found throughout the pluton. REE compositional patterns show a hybridization of Proterozoic and Mesozoic sources in some, but not all, Palms pluton granites. This data suggests that the pluton formed from multiple intrusions and the Proterozoic source remained relatively consistent throughout the pluton’s assembly with few additions of younger Mesozoic source material.
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A study of obsidian in prehistoric central and Eastern Europe, and it's trace element characterization. An analytically-based study of archaeological obsidian in Central and Eastern Europe, an investigation of obsidian sources in this area, and the characterization of these obsidians using neutron activation analysis.Thorpe, Olwen Williams January 1978 (has links)
Fieldwork in the Zemplen Mountain area of north-eastern
Hungary showed that there are at least eight geological
sources of obsidian here, five of which have obsidian of a
workable quality. There are a further three sources in the
Slovak Zemplen, all of which provide workable obsidian.
Sources in Central Slovakia are highly devitrified and not
useable, and reported sources in Rumania had been discounted
earlier (Nandris, 1975). Forty-six samples of obsidian
from the Zemplen sources, and 293 pieces from 87 archaeological
sites in Central and Eastern Europe, were analysed by neutron
activation analysis for 15 trace and two major elements.
The trace elements used included those which are geochemically
likely to show the greatest variation between different
obsidian sources, and which are not badly affected by
devitrification and hydration of the obsidian, for example
the rare earth elements. The analytical data was processed
using Cluster Analysis. 242 of the archaeological samples
came from Slovak sources, 22 from Hungarian sources, 9 from
Lipari and 5 from Melos. In addition, 6 samples were
tentatively assigned to Carpathian sources, and 9 could not
be assigned to any source. Obsidian from the Zemplen
Mountains was distributed up to a distance of approximately
480 km from the sources; it was used extensively in Slovakia
and Hungary and reached southern Poland, Austria, Moravia,
central Yugoslavia, north-east Italy and central Rumania.
Obsidian use in central and eastern Europe began in the
Mousterian period. The earliest pieces analysed were
Aurignacian and came from Hungarian sources. Later, in the
Gravettian, Slovakian sources began to be exploited and
remained predominant until obsidian use declined sharply in
the Later Neolithic, and Copper and Bronze Ages. The
Carpathian obsidian distribution overlaps with the Liparian
distribution at one site in north-east Italy. There is no
evidence for an overlap with Aegean or Near Eastern sources.
The rate of fall off of obsidian away from the sources
suggests a down-the-line trading mechanism.
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