No description available.

Fe und Cu wurden als Schlüsselspezies für die Betrachtung von Oberflächenkontamination in der Prozessierung von c-Si-Solarzellen identifiziert. Studien mit gezielt aufgebrachten Metallkonzentrationen vor verschiedenen Passivierungs- und Diffusionsprozessschritten ergaben relativ hohe kritische Werte für Cu, außer bei thermischer Oxidation. Niedrige Werte wurden für beide Elemente vor Hochtemperaturschritten im n-Typ-Hocheffizienzprozess beobachtet, wobei sich die B-Diffusion als etwas weniger empfindlich darstellte. Temporäre Gettereffekte für Fe (in p-Typ-Si) und Cu (in n-Typ-Si) wurden beobachtet. Es zeigte sich, dass As-Cut-Wafer, unabhängig von der Sägeart (SiC-slurry oder Diamantdraht) sehr hohe Metallverunreinigungen (im Bereich 1*1011 – 5*1014 cm-2) in den Prozess einbringen. Das alkalische Ätzen verringert diese Menge kaum, was hohe Anforderungen an die anschließende Reinigung ergibt. Die Optimierung von HF/O3-Reinigungslösung für diese Flächen ergab beste Reinigungsergebnisse bei niedrigen HF-Konzentrationen, abhängig vom alkalischen Ätzschritt und anschließendem HCl/HF-Dip.

O cobre (Cu) é um íon essencial para as plantas, animais e para a saúde humana. Em elevadas concentrações, este elemento pode ser extremamente tóxico para os organismos. A determinação das variáveis físico químicas da água, índice do estado trófico, alterações histológicas, o índice hepatosomático, bioacumulação do Cu nos tecidos branquial e hepático e marcadores de estresse oxidativo como superóxido dismutase (SOD), catalase (CAT), glutationa peroxidase (GPx) nos fígados foram realizados. Os resultados mostraram que as maiores concentrações estavam na fração Cu dissolvido, no período chuvoso. A exposição a maiores concentrações de Cu provocou alterações como, descolamento do epitélio basal das lamelas, aneurismas, fusão lamelar entre outros nas brânquias, vacuolização e necroses no fígado. Os fígados mostraram-se grandes acumuladores do metal, por outro lado, o índice hepatosomático apresentou uma diminuição em relação ao aumento do Cu. As atividades enzimáticas não apresentaram diferenças significativas, com exceção da CAT. De forma geral, as atividades das enzimas antioxidantes CAT, SOD e GPX, apresentaram alterações após 120 horas de exposição ao Cu, proveniente dos 4 pontos de coleta da Represa Guarapiranga. / Copper is an essential ion for plants, animals and for human health. Although the crucial role of Cu in several enzymatic processes, this heavy metal can exert adverse toxicological effects, when present in high concentrations in water. The determination of waters physic chemistry parameters, trophic index, histological alterations, hepatosomatic index, Cu bioaccumulation in livers and gills and oxidative stress enzymes like, CAT, SOD and GPX were done. Our results show that the higher values of Cu concentration were in the dissolved Cu and in the rainy season. The exposition o the fishes to a higher Cu concentrations altered the gills; aneurism, lamellar fusion, basal epithelium lifting. In the liver the alterations were, vacuolization and necrosis among others. The livers were the greatest bioaccumulation organs, and the other hand the hepatosomatic index decreased with higher Cu concentrations. There was no significant difference in the enzyme activities with the exception of CAT that increased with Cu increase, nevertheless in general, the enzyme activities of SOD, CAT and GPx were altered some how after 120 hours of Cu treatment, with water sample from 4 points located at Guarapiranga Reservoir.

O cobre (Cu) é um íon essencial para as plantas, animais e para a saúde humana. Em elevadas concentrações, este elemento pode ser extremamente tóxico para os organismos. A determinação das variáveis físico químicas da água, índice do estado trófico, alterações histológicas, o índice hepatosomático, bioacumulação do Cu nos tecidos branquial e hepático e marcadores de estresse oxidativo como superóxido dismutase (SOD), catalase (CAT), glutationa peroxidase (GPx) nos fígados foram realizados. Os resultados mostraram que as maiores concentrações estavam na fração Cu dissolvido, no período chuvoso. A exposição a maiores concentrações de Cu provocou alterações como, descolamento do epitélio basal das lamelas, aneurismas, fusão lamelar entre outros nas brânquias, vacuolização e necroses no fígado. Os fígados mostraram-se grandes acumuladores do metal, por outro lado, o índice hepatosomático apresentou uma diminuição em relação ao aumento do Cu. As atividades enzimáticas não apresentaram diferenças significativas, com exceção da CAT. De forma geral, as atividades das enzimas antioxidantes CAT, SOD e GPX, apresentaram alterações após 120 horas de exposição ao Cu, proveniente dos 4 pontos de coleta da Represa Guarapiranga. / Copper is an essential ion for plants, animals and for human health. Although the crucial role of Cu in several enzymatic processes, this heavy metal can exert adverse toxicological effects, when present in high concentrations in water. The determination of waters physic chemistry parameters, trophic index, histological alterations, hepatosomatic index, Cu bioaccumulation in livers and gills and oxidative stress enzymes like, CAT, SOD and GPX were done. Our results show that the higher values of Cu concentration were in the dissolved Cu and in the rainy season. The exposition o the fishes to a higher Cu concentrations altered the gills; aneurism, lamellar fusion, basal epithelium lifting. In the liver the alterations were, vacuolization and necrosis among others. The livers were the greatest bioaccumulation organs, and the other hand the hepatosomatic index decreased with higher Cu concentrations. There was no significant difference in the enzyme activities with the exception of CAT that increased with Cu increase, nevertheless in general, the enzyme activities of SOD, CAT and GPx were altered some how after 120 hours of Cu treatment, with water sample from 4 points located at Guarapiranga Reservoir.

Fe und Cu wurden als Schlüsselspezies für die Betrachtung von Oberflächenkontamination in der Prozessierung von c-Si-Solarzellen identifiziert. Studien mit gezielt aufgebrachten Metallkonzentrationen vor verschiedenen Passivierungs- und Diffusionsprozessschritten ergaben relativ hohe kritische Werte für Cu, außer bei thermischer Oxidation. Niedrige Werte wurden für beide Elemente vor Hochtemperaturschritten im n-Typ-Hocheffizienzprozess beobachtet, wobei sich die B-Diffusion als etwas weniger empfindlich darstellte. Temporäre Gettereffekte für Fe (in p-Typ-Si) und Cu (in n-Typ-Si) wurden beobachtet. Es zeigte sich, dass As-Cut-Wafer, unabhängig von der Sägeart (SiC-slurry oder Diamantdraht) sehr hohe Metallverunreinigungen (im Bereich 1*1011 – 5*1014 cm-2) in den Prozess einbringen. Das alkalische Ätzen verringert diese Menge kaum, was hohe Anforderungen an die anschließende Reinigung ergibt. Die Optimierung von HF/O3-Reinigungslösung für diese Flächen ergab beste Reinigungsergebnisse bei niedrigen HF-Konzentrationen, abhängig vom alkalischen Ätzschritt und anschließendem HCl/HF-Dip.

No description available.

Little is known regarding the impact excessive waterborne metals, like copper (Cu), have on tropical freshwater species. Zebrafish (Dania rerio) only recently became popular as a tool for environmental monitoring, due to their fully sequenced genome. Despite this, little was known regarding the ionoregulatory physiology of zebrafish. I first examined the impact softwater acclimation has on the ionoregulatory capacity of zebrafish, and identified a high degree of phenotypic plasticity associated with changes in both gene and protein expression, which highlighted the need for proper experimental design for studies involving pre-acclimation to softwater. I then examined the acute and chronic effects of waterborne Cu exposure under the influence of both softwater conditions and the addition of protective ions (Na+ & Ca2+) . On an acute timeframe, I found that Na+ provided a greater protective effect than Ca2+ in reducing Cu uptake, which was mimicked during chronic exposure, although the transcriptional effects were not as clear cut. I found that although Na+ and Ca2+ provided protective effects from Cu accumulation, there were still tissue specific and global changes at the transcript level, as determined by microarray analysis. Furthemore, this set of experiments identified the metal- and stress- induced transcriptional effects due to Cu exposure, which is key to identifying gene endpoints of chronic Cu exposure. A final experiment went further and looked at the effects of mixed metal contamination, examining chronic waterborne Cu exposure with interactive effects of elevated dietary Fe on gene expression and tissue metal accumulation. Not only did this experiment highlight that gene expression is not necessarily reflected in protein abundance/activity, but also demonstrated that high dietary Fe can significantly alter the transcriptional expression pattern of Cu transporters in the gill, liver, and gastrointestinal tract. This thesis has made significant steps in identifying viable gene endpoints of Cu toxicity. / Thesis / Doctor of Philosophy (PhD)

Cette thèse s’intègre dans l’axe 3 du programme « ETIAGE » qui a associé pendant quatre ans (2010-2014) la Lyonnaise des Eaux, la Communauté Urbaine de Bordeaux (CUB), l’AEAG, et le FEDER, région Aquitaine avec l’université de Bordeaux, le CNRS et IRSTEA. L’objectif de l’axe 3 était de documenter les apports métalliques du bassin versant de la CUB aux eaux de la section garonnaise de l’estuaire de la Gironde. Ce vaste estuaire européen est l’un des plus turbides au monde, avec en période d’étiage la présence devant Bordeaux d’une zone de turbidité maximum (ZTM, >1 g.L-1 de MES en surface) qui transporte des particules estuariennes et des éléments traces potentiellement toxiques. Les travaux de cette thèse se sont focalisés sur les apports métalliques via le fonctionnement des deux principales stations d’épuration (STEP) de la CUB. De ce fait, l’objectif de cette recherche est d’analyser en détail les concentrations, les flux et la réactivité de huit contaminants métalliques définis comme prioritaires par l’Union Européenne Cr, Cu, Cr, Hg, Ni, Pb, Zn, As, et le contaminant émergent Ag, des STEP de la CUB. Les taux d’abattement calculés sont importants, de l’ordre de 80 % pour la majorité des métaux, essentiellement lors de l’étape de décantation. Malgré cette efficacité, les apports en éléments traces métalliques (ETM) urbains via les STEP pendant les épisodes orageux et dans des situations de faible débit peuvent augmenter les concentrations et les flux dans l’estuaire fluvial de la Gironde et ainsi avoir des conséquences sur la qualité des eaux estuariennes. Les concentrations en Ag sont supérieures aux concentrations normales de bruit de fond dans l’estuaire fluvial de la Gironde, faisant de Ag un excellent traceur urbain. Le traitement dans les STEP concentre les ETM dans les boues extraites dont les concentrations métalliques restent en-deçà des normes d’épandage. Toutefois, les concentrations en éléments traces peuvent être de 15 (Ag) à 30 (Cu) fois supérieures aux concentrations naturelles du bruit de fond en raison du fort enrichissement des boues en Hg, Ag, Cr, Cu et Zn. De plus, environ 70 % des éléments traces Cd, Ag, Pb, Cu, et Zn contenus dans ces boues sont potentiellement biodisponibles et peuvent avoir un impact néfaste à court et long terme sur les environnements récepteurs. En raison de l’augmentation prévisible de la démographie des villes côtières, les résultats de cette étude participent à l’élaboration de nouveaux concepts et outils (récupération, recyclage, valorisation) pour améliorer quantitativement et qualitativement les rejets urbains solides et liquides. / This study is a part of the third axis of the « ETIAGE » project, a four year collaboration (2010-2014) between the Lyonnaise des Eaux, the Communauté Urbaine de Bordeaux (CUB), AEAG, and FEDER, Aquitaine region with the University of Bordeaux, CNRS and IRSTEA. The axis 3 objectives were to document the trace metal inputs from the CUB watershed into the waters of the Garonne section of the Gironde estuary. The Gironde Estuary is one of the largest macrotidal and highly turbid estuaries in Western Europe characterized by the presence of a strong maximum turbidity zone (MTZ) with high suspended particulate matter (SPM) concentrations (>1 g.L-1 in surface water) transporting estuarine particles and potentially hazardous trace elements. This study has focused on the trace metal inputs from the two main wastewater treatment plants (WWTP) of the CUB. The objective of this research was therefore to study in detail the daily concentrations, fluxes, and dynamics of 8 EU priority contaminants Cr, Cu, Cr, Hg, Ni, Pb Zn, As, and the emerging contaminant Ag from the WWTPs in the CUB. The calculated removal rates are significant, around 80 % for the majority of metals, mainly as a result of the decantation phase. Despite this high removal efficiency, during periods of heavy rainstorms and low river discharges, the urban metal inputs via the WWTPs may still significantly increase metal concentrations and fluxes in the fluvial Gironde Estuary impacting water quality. In addition, the WWTP fluxes and concentrations of Ag exceeded common background concentrations in the Gironde fluvial estuary, making it an interesting urban tracer. The treatment within the WWTPs concentrates the trace metals in the sludge, yet, metal concentrations remained below legal norms for agricultural use. However, the analysis of WWTP sludge revealed that trace element concentrations are 15 (Ag) and 30 (Cu) times higher than natural background concentrations with high enrichment of Hg, Ag, Cr, Cu and Zn with over 70 % of Cd, Ag, Pb, Cu, and Zn being potentially bioavailable. Therefore, with increasing urban pressure on environmental quality, these results support the need for the development of efficient water quality monitoring tools.

This study took place in Malawi, south eastern Africa. Metal contamination of water and soil is a threat to the environment and human health and is a serious concern in many countries including Malawi. Blantyre is the city of commerce where most of the industry is located along the banks of the main rivers. Some of the industries produce wastewater, which due to poor access to wastewater treatment plants, is discharged without treatment into the environment. A match factory in Blantyre uses chromium as a colouring agent for match heads and very high concentrations of chromium(VI) have been measured downstream the factory with concentrations up to 56 mg/l, which is much higher than the WHO guidelines of 0.05 mg/l.  Chromium(VI) mainly occurs as chromate CrO42- and dichromate Cr2O72- ions. They are both toxic and carcinogenic and can cause mutations and chromosomal aberrations.   The aim of the study was to evaluate the efficiency of Granular Ferric Hydroxide (GFH) in adsorbing and removing chromium from an aqueous phase. Wastewater was collected from the match factory and by optimizing relevant parameters the removal efficiency was maximized. The parameters optimized were pH, dosage and contact time and the effect of initial concentration. After respective experiment, all samples were analysed for chromium using microwave plasma atomic emission spectroscopy (MP-AES).   The optimum pH was chosen to 8.0, the dosage to 17.4 g GFH/l and the contact time to 2 hours for a 95% removal of total chromium in undiluted wastewater. The removal efficiency of the GFH was 2.84 mg Cr/g GFH. To implement wastewater purification with GFH a number of practical issues have to be taken into consideration. Above all, a sufficient stirring method has to be devised as the removal efficiency is much affected by improper stirring. / Denna studie genomfördes i Malawi, sydöstra Afrika. Metallföroreningar i vatten och mark är ett stort problem i många länder, inklusive Malawi. Landets centrum för industri och handel ligger i Blantyre där de flesta av industrierna ligger längs med floderna. En del industrier genererar utsläppsvatten och på grund av dålig tillgång till vattenreningsteknik och vattenreningsanläggningar släpps mycket av det förorenade vattnet obehandlat ut i naturen. En tändsticksfabrik i Blantyre använder kromsalter för att färga tändstickshuvudena röda och höga koncentrationer av sexvärt krom har uppmätts nedströms fabriken. De uppmätta koncentrationerna var upp till 56 mg/l vilket är betydligt högre än WHO:s riktvärde på 0,05 mg/l. Sexvärt krom förekommer som kromat CrO42- och dikromat Cr2O72- joner vilka båda är mycket toxiska och cancerframkallande och därmed ett hot mot miljö och människor. Syftet med studien var att undersöka om granulära järnoxider (GFH) kunde användas som en adsorbent för att rena utsläppsvatten från kromater. Utsläppsvatten hämtades från tändsticksfabriken och genom att optimera relevanta parametrar kunde GFHns adsorbtionseffektivitet maximeras. Parametrarna som optimerades var pH, dos, kontakttid och initialkoncentration. Efter respektive experiment mättes kromkoncentrationen med mikrovågsplasma atomemissionsspektroskopi (MP-AES) Det optimala pH-värdet valdes till 8.0, dosen till 17.4 g GFH/l med en kontakttid på 2 timmar för en 95.3% reningsgrad på outspätt utsläppsvatten. Adsorptionseffektiviteten på GFHn var 2.84 mg Cr/g GFH. För att implementera vattenrening med GFH behöver flera praktiska aspekter tas med i beaktning. Framförallt är det viktigt med en bra omrörning för att GFHn ska kunna adsorbera effektivt.

A busca por medidas sustentáveis para melhorar e suprir a demanda por alimentos que o crescimento populacional exige, aliado a escassez de terras produtivas, além do acúmulo excessivo de metais no ambiente devido a atividades como mineração e aplicação de fertilizantes no solo, foram as duas problemáticas que motivaram o presente estudo. O uso de fungos promotores do crescimento vegetal: Beauveria bassiana, Metarhizium anisopliae, Pochonia chlamydosporia, Purpureocillium lilacinum e Trichoderma asperella, pode tanto vir a influenciar o aumento da produtividade como potencializar a fitorremediação de metais pesados no solo. Esses fatos são explicados pela capacidade do consórcio fúngico de sintetizar e induzir as plantas a produzir fitohormônios direcionados para o melhor desenvolvimento das raízes do hospedeiro. O maior desenvolvimento de raízes pode estimular a fitoextração de metais do solo e conferir tolerância das plantas à contaminação. Na intenção de avaliar a influência dos fungos no desenvolvimento das plantas, foram realizados tratamentos das sementes de soja e milho e aplicação na parte aérea da cultura da cana-de-açúcar. Já para analisar a influência desses organismos no processo de fitorremediação de Cu, Zn e Mn em colunas de solos cultivados com Jacaranda mimosifolia D. Don, os fungos foram inoculados no solo e na parte aérea das plantas. Todos os tratamentos tiveram 6 repetições e suas médias foram submetidas à análise de variância e teste de média ao nível de 5% de probabilidade. O consórcio fúngico condicionou o crescimento de raízes de soja e milho, aumentou a colonização micorrízica arbuscular em soja e cana-de-açúcar. No jacarandá, os fungos melhoraram o desenvolvimento de raízes e parte aérea, maior acúmulo de Mn e Zn na planta, melhor translocação de Mn e Zn das raízes para a parte aérea, além de diminuir o estresse fisiológico. Além disso, a aplicação conjunta de fungos e biochar nas mudas proporciona proteção à sua atividade fotossintética e reduz o risco ambiental de contaminação por metais por diminuir o total de Cu, Mn e Zn lixiviado. O biochar foi adquirido por meio da pirólise lenta do resíduo do beneficiamento da madeira de eucalipto e aplicado superficialmente no solo. Com isso, esse estudo mostrou que os fungos utilizados apresentam potencial para colaborar com o aumento da produtividade de culturas comerciais e colaborar com a melhoria na remediação de solos contaminados com íons metálicos. / The search for sustainable measures to improve and meet the demand for food that population growth requires, combined with the scarcity of productive land, in addition to the excessive accumulation of metals in the environment due to activities such as mining and application of soil fertilizers, were the two problems that motivated the present study. The use of fungi plant growth promoters: Beauveria bassiana, Metarhizium anisopliae, Pochonia chlamydosporia, Purpureocillium lilacinum and Trichoderma asperella can both influence on increasing productivity as the phytoremediation of heavy metals in the soil. These facts are explained by the capacity of the fungal Consortium to synthesize and induce plants to produce phytohormone targeted for the better development of the roots of the host. The further development of roots can stimulate phytoextraction of metals from the soil and give plants tolerance to contamination. In order to evaluate the influence of fungi on the development of plants, were done seed treatments of soybeans and corn and application in aerial part of the culture of sugar cane. To analyze the influence of these organisms in the process of phytoremediation of Cu, Zn and Mn in soil columns cultivated with Jacaranda mimosifolia D. Don, fungi were inoculated in soil and aerial part of plants. All treatments had 6 reptitions and their averages were subjected to analysis of variance and average test at 5% probability. The fungal consortium has conditioned the growth of roots of soybeans and corn, mycorrhizal colonization increased in soybeans and sugar cane. In jacarandá, fungi have improved the development of roots and shoots, greater accumulation of Mn and Zn in plant, best of Mn and Zn translocation from roots to shoots, in addition to decrease physiological stress. In addition, the joint application of fungus and biochar in seedlings provides protection to photosynthetic activity and reduces the risk of environmental contamination by metals by decreasing the amount of Cu, Mn and Zn leached. The biochar was acquired through the slow pyrolysis of the eucalyptus wood processing residue and applied superficially to the soil. With that, this study showed that fungi used present potential to contribute to the increased productivity of commercial crops and contribute to the improvement in the remediation of soils contaminated with metal ions. / Dissertação (Mestrado)