Dissertations / Theses: 'Sulfat'

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Fernández, Palacios Eva. "Integrated assessment of long-term sulfidogenesis in UASB reactors using crude glycerol as carbon source." Doctoral thesis, Universitat Autònoma de Barcelona, 2020. http://hdl.handle.net/10803/670499.

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Moltes activitats industrials generen emissions que contenen compostos de sofre tant en efluents líquids com emissions gasoses, que majoritàriament són tractades mitjançant processos fisicoquímics. El sulfat es troba generalment a les aigües residuals d’aquestes indústries, com la indústria paperera, la farmacèutica, la minera o l’alimentària. Com a tal, el sulfat no és un compost nociu, però si s’aboca als rius o sistemes de clavegueram, pot generar-se un desequilibri del cicle del sofre. Dins d’aquest cicle, el producte final de la reducció de compostos és el sulfur d’hidrogen (H2S). Aquest compost és corrosiu, olorós i s’ha demostrat que és tòxic en baixes concentracions. Per aquests motius, és necessari desenvolupar alternatives respectuoses amb el medi ambient per a tractar i valoritzar no només les emissions de SO2 sinó també els efluents líquids rics en sofre. A més, podria recuperar-se sofre elemental d’aquests efluents, la qual cosa brindaria l’oportunitat de recuperar recursos en el marc de l’economia circular. Amb aquestes premisses, el projecte SONOVA, en el qual s’emmarca aquesta tesi, va desenvolupar un procés integral de tractament del SOx i el NOx provinent de gasos de combustió mitjançant processos biològics, econòmics, robustos i respectuosos amb el medi ambient que també tenen en compte la reutilització d’energia i recursos al llarg del procés, així com la valorització de residus. El procés proposat es basa en una primera doble etapa per a l’absorció selectiva de SOx i NOx; una segona etapa biològica per a reduir el sulfat de la primera etapa d’absorció a sulfur d’hidrogen (que és l’objectiu d’estudi d’aquesta tesi); i una tercera etapa biològica per a l’oxidació del sulfur d’hidrogen a sofre elemental i la seva posterior recuperació. El desenvolupament de sistemes biològics, com el reactor de llit anaerobi amb flux ascendent (UASB), han estat implementats per al tractament de diverses aigües residuals i per a la digestió anaeròbia. En aquesta tesi, s’ha estudiat l’ús d’aquest tipus de reactor UASB pel tractament d’aigües sintètiques amb sulfat, específicament, es va seleccionar el glicerol cru com a font de carboni i donador d’electrons. Es van utilitzar tant processos fisicoquímics com tècniques de biologia molecular per a obtenir un major coneixement del procés. Es va estudiar la influència de possibles inhibicions i la competència entre els bacteris reductors de sulfat i els metanògens a fi de millorar l’eliminació de sulfat i la producció de sulfur. Es va observar que en les operacions a llarg termini (després de 200 dies aproximadament) els metanògens desapareixen del sistema i els bacteris reductors del sulfat són els que colonitzen. No obstant això, es va observar una acumulació d’acetat a conseqüència de la desaparició dels metanògens, la qual cosa va donar lloc a una pèrdua de la font de carboni a la sortida del reactor que podria haver-se utilitzat per a produir sulfur. Les operacions a llarg termini permeten detectar altres limitacions del sistema. Al llarg de les operacions en UASB dutes a terme en aquesta tesi, es va observar una pèrdua de l’estructura granular i el creixement d’una biopel·lícula no metanogènica ni sulfat reductora no identificada. Aquesta biopel·lícula, anomenada slime al llarg d’aquesta tesi, es va considerar com un factor crucial que afectava el sistema biològic, conferint propietats com la viscositat al llit granular. En conseqüència, es van poder observar problemes relacionats amb la limitació de transferència de matèria, que afectava també l’activitat sulfat reductora dels grànuls i que va conduir a operacions fallides.
Muchas actividades industriales generan emisiones que contienen compuestos de azufre tanto en efluentes líquidos como emisiones gaseosas, que mayoritariamente son tratadas mediante procesos fisicoquímicos. El sulfato se encuentra generalmente en las aguas residuales de estas industrias, como la industria papelera, la farmacéutica, la minera o la alimentaria. Como tal, el sulfato no es un compuesto nocivo, pero si se vierte en los ríos o en los sistemas de alcantarillado, puede generarse un desequilibrio en el ciclo del azufre. Dentro de este ciclo, el producto final de la reducción de compuestos dentro del mismo es el sulfuro de hidrógeno (H2S). Este compuesto es corrosivo, oloroso y se ha demostrado que es tóxico en bajas concentraciones. Por estos motivos, es necesario desarrollar alternativas respetuosas con el medio ambiente para tratar y valorizar no sólo las emisiones de SO2 sino también los efluentes líquidos ricos en azufre. Además, podría recuperarse azufre elemental de esos efluentes, lo que brindaría la oportunidad de recuperar recursos en el marco de la economía circular. Con estas premisas, el proyecto SONOVA, en el cual se enmarca esta tesis, desarrolló un proceso integral de tratamiento del SOx y el NOx proveniente de gases de combustión mediante procesos biológicos, económicos, robustos y respetuosos con el medio ambiente que también tienen en cuenta la reutilización de energía y recursos a lo largo del proceso, así como la valorización de residuos. El proceso propuesto se basa en una primera doble etapa para la absorción selectiva de SOx y NOx; una segunda etapa biológica para reducir el sulfato de la primera etapa de absorción a sulfuro de hidrógeno (que es el objetivo de estudio de esta tesis); y una tercera etapa biológica para la oxidación del sulfuro de hidrógeno a azufre elemental y su posterior recuperación. El desarrollado de sistemas, como el reactor de lecho de lodo anaerobio de flujo ascendente (UASB), han sido implementados para el tratamiento de diversas aguas residuales y para la digestión anaerobia. En esta tesis, se estudió el uso de este tipo de reactor UASB para el tratamiento de aguas sintéticas con sulfato, específicamente, se seleccionó el glicerol crudo como fuente de carbono y donador de electrones. Se utilizaron tanto procesos fisicoquímicos como técnicas de biología molecular para obtener un mayor conocimiento del proceso. Se estudió la influencia de posibles inhibiciones y la competencia entre las bacterias sulfato reductoras y los metanógenos a fin de mejorar la eliminación de sulfato y la producción de sulfuro. Se observó que en las operaciones a largo plazo (después de 200 días aproximadamente) los metanógenos desaparecen del sistema y las bacterias sulfato reductoras son las que lo colonizan. Sin embargo, se observó una acumulación de acetato como consecuencia de la desaparición de los metanógenos, lo que dio lugar a una pérdida de la fuente de carbono en la salida del reactor que podría haberse utilizado para producir sulfuro. Las operaciones a largo plazo permiten detectar otras limitaciones del sistema. A lo largo de las operaciones del UASB llevadas a cabo en esta tesis, se observó una pérdida de la estructura granular y el crecimiento de una biopelícula no metanogénica ni sulfatoreductora no identificada. Esta biopelícula, llamada slime a lo largo de esta tesis, se consideró como un factor crucial que afectaba a nuestro sistema, confiriendo propiedades como la viscosidad al lodo granular. En consecuencia, se pudieron observar problemas relacionados con la limitación de transferencia de materia, que afectaba también a la actividad sulfato reductora de los gránulos y que condujo a operaciones fallidas.
Many industrial activities generate effluents containing sulfur compounds, both as liquid or gaseous emissions, which are mainly treated through physical-chemical processes. Sulfate is generally present in wastewaters coming from paper, pharmaceutical, mining or food processing industries, among others. As such, sulfate is not a harmful compound, but if it is poured into rivers or sewage systems, an imbalance in the overall sulfur cycle can be generated. Inside this cycle, the last product after the reduction of sulfur compounds is hydrogen sulfide (H2S). This compound is corrosive, odorous and toxic at low concentrations. For these reasons, there is a need to develop environmentally friendly alternatives to valorize not only gaseous emissions, such as SO2 emissions, but also S-rich liquid effluents. In addition, a further recovery of elemental sulfur from these effluents could be obtained providing an opportunity to recover resources in the framework of the circular economy. With these premises, the SONOVA project, in which this thesis is enclosed, is based in the development of a comprehensive treatment process to valorize SOx and NOx from flue gases by economical, robust and environmentally friendly biological methods. It also takes into account the reuse of energy and resources along the process as well as residues valorization. The proposed process is based on a first double stage for selective absorption of SOx and NOx; a second biological step for reducing the sulfate from the first absorption stage to hydrogen sulfide (which is the focus of this thesis); and a third biological stage for the oxidation of hydrogen sulfide to elemental sulfur and its subsequent recovery. Biological-based systems, such as Up-flow Anaerobic Sludge Bed (UASB) reactors, have been developed and implemented world-wide to treat many types of wastewater and to produce biogas through anaerobic digestion. In this thesis, the use of an UASB reactor for the treatment of synthetic wastewater with sulfate was studied, specifically selecting crude glycerol as carbon source and electron donor. Both physical-chemical processes and molecular biology techniques were used to get a broad knowledge of the anaerobic process. The influence of possible inhibitions and competition between sulfate reducers and methanogens was studied in order to improve sulfate removal and sulfide production. It was observed that in long-term operations (after 200 days approximately) methanogens were washed out from the system and sulfate reducers colonized the reactor sludge. However, acetate accumulation was observed because of the disappearance of methanogens, leading to a loss of carbon source in the outlet of the reactor that could have been used to produce sulfide in the UASB. Long-term performances allow detecting further limitations of the system. A loss of granular structure and the growth of unidentified non-sulfate reducer, non-methanogenic biofilm was observed during UASB operations along this thesis. This biofilm, called slime substance along this thesis, was found to be a crucial factor affecting our system, conferring properties such as viscosity to the sludge. Consequently, problems related to mass transfer limitations could be observed, affecting as well, the sulfate reducing activity of the granules and leading to failure operations. Finally, since the accumulation of acetate could not be avoided, experiments were designed to pursue the enrichment of acetate degrading sulfate reducing bacteria in serum bottles, with the final objective of improving sulfidogenesis. In addition, isolation of potential acetate-utilizing sulfate reducers was also pursued. Unfortunately, a culture able to perform sulfate reduction with acetate was not developed during the enrichment experiments. Therefore, further research is needed to enhance the operation in terms of organic matter consumption and sulfide productivity in the long-term.

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Green, Carsten. "Ramanspektroskopische und elektrophoretische Untersuchungen an wässrigen Sulfat- und Nitratlösungen." [S.l.] : [s.n.], 2002. http://e-diss.uni-kiel.de/diss_543/d543.pdf.

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Hoins, Ulrich. "Zur Schwermetall-Adsorption an oxidischen Oberflächen : der Einfluss von Sulfat /." [S.l.] : [s.n.], 1991. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=9628.

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Mata, Ramirez Jorge Octavio. "Caracterización de las Transiciones de Fase de las Cerámicas Ferroeléctricas del tipo Li-sub2(MM')(SO-sub4)super2 en donde M = Na+, K+, NH-sub4+." Doctoral thesis, Universitat de Barcelona, 2002. http://hdl.handle.net/10803/1257.

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El trabajo de esta tesis ha consistido en estudiar, preparar y caracterizar los compuestos pertenecientes a la familia M'M"BX-sub4, concretamente los de fórmula LiMSO-sub4, en donde M = Na+, K+ y NH-sub4+, para posteriormente estudiar los cristales mixtos de fórmula Li2MM'(SO-sub4)-super2 formados a partir de la mezcla de estos compuestos.
La caracterización de las fases puras a diferentes temperaturas se ha efectuado mediante Difracción de Rayos-X, trabajando tanto con muestras monocristalinas como con muestras en polvo y variando la temperatura de medida de los difractógramas a diferentes velocidades de calentamiento. Se han utilizado también Análisis Térmico (ATD, TG y DSC) y Dispersión Raman.
La estructura cristalina de los compuestos de la familia LiMSO-sub4 presenta una gran facilidad de rotación de los iones SO-sub4-super2- y desplazamiento de los cationes lo que facilita no sólo la aparición de numerosas transiciones de fases si no también la facilidad de producir cristales maclados y la formación de nuevas fases dependientes del proceso de crecimiento de los cristales. Se ha demostrado la aparición de nuevas fases modificando la proporción de NH-sub4+ en el proceso de cristalización del LiKSO-sub4 o cambiando la velocidad de calentamiento en el LiNH-sub4SO-sub4.
Se ha conseguido generar nuevas fases que difieren por la rotación del ion sulfato provocando fases con diferente enantiomorfismo e incluso se ha conseguido caracterizar fases formadas por la mezcla de dos tipos de dominios. Los compuestos con presencia del ion K+ son los que presentan una mayor polarización espontánea, mientras que los compuestos con mayor presencia de Na+ son los que presentan una mayor conductividad iónica.
Los diferentes tipos estructurales que presenta cada compuesto dificulta la misciblidad entre ellos, para el caso del compuesto LiKSO-sub4, una nueva transición de fase se describe a entre 226 y 268 K. La transición entre la fase V y VI es del tipo orden-desorden, mientras que las restantes transiciones estudiadas en el LiKSO-sub4 son de tipo displacivo o de desplazamiento. Mientras que las transiciones por debajo de la temperatura ambiente se caracterizan por una rotación en torno al eje c de los iones sulfatos. Todas estas transiciones presentan histéresis térmica.
Para el caso del LiNH-sub4SO-sub4 las fases que presenta por encima de la temperatura ambiente dependen de la velocidad de calentamiento y ellas son transiciones displacivas. Para el caso del LiNaSO-sub4; todas las cristalizaciones de este compuesto han sido cristales maclados. Se describe estructuralmente un nuevo compuesto de fórmula: Li-sub2-subx-Na-subx-SO-sub4 con 1 menor que "x" menor que 1.22.
Para el caso de la estructura de triple catión Li(NH-sub4)sub1-xK-subxSO-sub4 y LiNa-sub1-sub-xK-subx-SO-sub4 La miscibilidad del ión NH-sub4+ en la estructura del LiKSO-sub4 y del K+ en la estructura del LiNaSO-sub4 es muy restringida a temperatura ambiente. La formación del Li-sub-2KNH-sub4(SO-sub4)sub2 a partir de una solución acuosa a 333 K debe efectuarse mezclando en la proporción 1:9, del LiKSO-sub4 : LiNH-sub4-SO-sub4. La proporción esta definida básicamente por la mayor solubilidad del LiNH-sub4-SO-sub4 con respecto al LiKSO-sub4. La fase a temperatura ambiente es ferroeléctrica, presentando una transición Martensítica.

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Siebert, Björn. "Betonkorrosion infolge kombinierten Säure-Sulfat-Angriffs bei Oxidation von Eisendisulfiden im Baugrund." Aachen Shaker, 2009. http://d-nb.info/1001353641/04.

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Lamanna, William Christopher. "Functional characterization of the novel heparan sulfate 6O-endosulfatases Sulf1 and Sulf2." Göttingen Cuvillier, 2008. http://d-nb.info/989809897/04.

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Lux, Philipp Alexander. "Untersuchungen zum Anteil der Leber an der Interkonversion von Dehydroepiandrosteron und Dehydroepiandrosteron-Sulfat." Doctoral thesis, kostenfrei, 2008. http://nbn-resolving.de/urn/resolver.pl?urn=nbn:de:bvb:20-opus-31483.

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Undin, Klara. "Vattenrening i textilåtervinningsindustri : Reducering av nonylfenol, bromerade flamskyddsmedel och sulfat i re:newcells processvatten." Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-78765.

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Kläder och textilier produceras och konsumeras i allt högre grad med stor påverkan på miljö, klimat och jordens resurser som följd. En attraktiv lösning på det är återvinning av kläder, vilket företaget re:newcell gör. Detta är en förstudie med syfte att undersöka vilka reningsmetoder re:newcell skulle kunna implementera för att förbättra sin vattenreningsprocess i framtiden. Tre ämnen vars halter i nuläget inte reduceras i reningen valdes ut till studien: nonylfenol, bromerade flamskyddsmedel och sulfat. En litteraturstudie kring dessa ämnen och möjliga reningsmetoder resulterade i att tre lämpliga reningsmetoder valdes ut till studien: ozonering, biologisk rening och jonbyte. En försöksplan utformades med målen att ta reda på (1) hur tidigare rapporterade ozondoser påverkade nonylfenolhalten i re:newcells vatten, (2) hur stor andel TOC (Total Organic Carbon) en MBBR (moving body bioreactor) kunde reducera och (3) ifall PBDE (bromerade flamskyddsmedel) och sulfat var möjliga att bryta ner med i en MBBR, (4) hur stort jonbytarfilter som skulle krävas i re:newcells process för att reducera sulfathalten samt (5) i vilken ordning reningsstegen bör implementeras i framtida reningsprocesser. Ozoneringsförsök utfördes på re:newcells laboratorium i Kristinehamn med totalt fem olika ozondoser. En biologisk MBBR utformades i laboratorium på Karlstad Universitet, där två olika uppehållstider testades för reducering av flamskyddsmedel, sulfat och TOC. Beräkningar på jonbytarfilter utfördes teoretiskt. En ozondos på 0,45 mgO3/mgCOD gav en reducering på ca 31 % och 0,75 mgO3/mgCOD gav 78 % reducering vid en nonylfenolhalt på 1100 mg/L. Resultaten från MBBR visar att bakterier trivs i re:newcells vatten och att de kunde reducera TOC med ca 50 %. Däremot kunde ingen reducering av sulfat uppmätas, vilket tyder på att ingen anaerob zon har uppstått. Halten av PBDE reducerades med ca 90 % med en uppehållstid på 45 h i MBBR, men om det beror på nedbrytning eller adsorption till slammet är inte fastställt. Resultaten från beräkningen på jonbytarfiltret visade att filtret behöver vara 5,7-15 m3 vid regenerering en gång per dygn i re:newcells nuvarande pilotskaliga process. Denna metod anses därmed inte vara en lämplig för sulfatreducering. Den framtida reningsprocessen föreslås starta med MBBR och efterföljande sedimentering, följt av kemfällning, sedimentering/flotation, sandfilter, ozonering och sist aktivkolfilter, men vidare studier rekommenderas rörande vilken ordning reningsstegen bör implementeras för optimal effekt. Vidare studier kring vilken ozondos som krävs och vilken uppehållstid som är optimal i MBBR föreslås också.
Clothes and textiles are increasingly produced and consumed causing a major impact on the environment, the climate and the earth's resources. One solution to the problem is to recycle clothes that are no longer used, which is what the company re:newcell does. This is a feasibility study aimed at investigating what purification methods re:newcell could implement to improve their water purification process in the future. Three substances not currently purified sufficiently were selected for the study: nonylphenol, brominated flame retardants and sulfate. A literature review on these substances and possible purification methods for them resulted in that the following methods were selected for the study: ozonation, biological purification and ion exchange. An experimental plan was developed with the aim of finding out (1) how previously reported ozone doses affected the nonylphenol content in re:newcell's water, (2) how much TOC an MBBR (moving body bioreactor) could reduce, (3) and whether the levels of brominated flame retardants and sulphate were possible to reduce in it, (4) the required size of the ion exchange filter in re:newcells process to reduce sulfateand (5) the order in which the purification steps should be implemented in future purification processes. Ozonation experiments were carried out at re:newcell's laboratory in Kristinehamn with a total of five different ozone doses tested. A biological MBBR was designed in a laboratory at Karlstad University, where two different hydraulic retention times were tested for reducing flame retardants, sulfate and TOC. Calculations on ion exchange filters were performed theoretically. An ozone dose of 0.45 mgO3/mgCOD produced a reduction of about 31% and 0.75 mgO3/mgCOD produced a 78% reduction at a nonylphenol content of 1100 µg / L The results from MBBR showed that bacteria thrived in re:newcell´s water and that they can reduce TOC by about 50 %. However, reduction of sulfate could be measured, suggesting that no anaerobic zone has occured. The content of PBDE was reduced by about 90% with a hydraulic retention time of 45 hours in MBBR, but whether it is due to degradation or adsorbation to the sludge is not determined. The calculation regarding the ion exchange filter show that the filter needs to be 5,7-15 m3 when regenerated once a day in re:newcell's current pilot scale process this method is therefore not considered appropriate for sulfate reduction for re:newcell. The future purification process is proposed to start with MBBR and subsequent sedimentation, followed by chemical precipitation, sedimentation / flotation, sand filter, ozonation and last activated carbon filter, but further studies are recommended regarding which order the purification steps should be implemented for optimal effect. Further studies on which ozone dose is required and which residence time is optimal in MBBR are also suggested.

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Siebert, Björn [Verfasser]. "Betonkorrosion infolge kombinierten Säure-Sulfat-Angriffs bei Oxidation von Eisendisulfiden im Baugrund / Björn Siebert." Aachen : Shaker, 2010. http://d-nb.info/112436420X/34.

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SEGUI, P. N. "Utilização de nitrato para bioatenuação da geração de sulfeto em água produzida proveniente da extração de petróleo." Universidade Federal do Espírito Santo, 2009. http://repositorio.ufes.br/handle/10/3904.

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Made available in DSpace on 2016-08-29T15:09:43Z (GMT). No. of bitstreams: 1 tese_3107_Dissertao_Paula Segui.pdf: 1369579 bytes, checksum: 0a772a2ec88ad7d51bd2ea2f285962c1 (MD5) Previous issue date: 2009-02-18
Em sistemas e processos industriais, incluindo processos de tratamento de águas residuárias e sistemas de exploração e produção de petróleo, a geração de sulfeto e a corrosão influenciada por microrganismos trazem prejuízos incalculáveis em todo mundo. A indústria de petróleo tem se empenhado em desenvolver novas tecnologias para o tratamento da água produzida, gerada nos processos de exploração, no intuito de minimizar a biocorrosão nos dutos e materiais metálicos, e os possíveis danos ambientais. O grupo de microrganismos conhecido como microrganismos redutores de sulfato (MRS) possui como principal característica a redução do sulfato a sulfeto no processo de degradação anaeróbia da matéria orgânica. Além da importância ecológica no ciclo do enxofre e do carbono, os MRS estão relacionados à corrosão microbiológica e à geração de odores, sendo que a indústria petrolífera se destaca como umas das que mais são afetadas pela atividade deste grupo de microrganismos. O nitrato é uma alternativa mais econômica em ralação aos biocidas, normalmente utilizados no tratamento da água produzida, além de não oferecer riscos ambientais. O presente trabalho avaliou a utilização de nitrato para a diminuição da geração de sulfeto por microrganismos redutores de sulfato em amostras de água produzida, fornecidas pela Petrobras. O experimento foi planejado utilizando tratamentos envolvendo três níveis de nitrato, dois níveis de acetato (presença e ausência) e três repetições, com controles de água produzida, água produzida + lodo e água produzida + lodo + acetato, totalizando 27 unidades experimentais. Os resultados indicaram que o nitrato na concentração intermediária (500 mg/L) foi suficiente para cessar a geração de sulfeto pelos microrganismos redutores de sulfato, num período entre 3 e 4 semanas após o início do experimento. Além disso, a análise estatística dos dados incluiu as amostras em que houve adição de acetato, como aumento da fonte de carbono, num mesmo grupo de médias em relação às mesmas amostras, porém, sem a adição de acetato.

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Cassidy, Joana. "Optimization of biological sulphate reduction to treat inorganic wastewaters : process control and use of methane as electron donor." Thesis, Paris Est, 2014. http://www.theses.fr/2014PEST1177/document.

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Ce travail a étudié deux approches différentes pour optimiser la réduction biologique des sulfates: la première approche consisté à élaborer une stratégie de contrôle de processus pour optimiser l'ajout d'un donneur d'électrons et la deuxième à vérifier la pertinence de l'utilisation d'une source de carbone bon marché, à savoir, le méthane. Une stratégie de contrôle de l'apport du donneur d'électron en se basant sur le suivi de la charge organique a été mis en place. Des conditions d'abondance et de famine ont été appliquées à un bioréacteur à bactéries sulfato-réductrices (BSR) pour stimuler les dynamiques du processus. Ces conditions d'abondance/famine ont donné lieu à l'accumulation de carbone et également de soufre élémentaire (composants de stockage de biomasse réductrice de sulfate). Cette étude a montré que les retards dans le temps de réponse et un gain de commande élevé peuvent être considérés comme les facteurs les plus critiques affectant l'application d'une stratégie de contrôle de sulfure dans des bioréacteurs à BSR. L'allongement du temps de réponse est expliqué par l'induction de différentes voies métaboliques au sein des communautés microbienne des boues anaérobies, notamment par l'accumulation de sous produits de stockage. Le polyhydroxybutyrate (PHB) et les sulfates ont été retrouvés accumulés par la biomasse présente dans le bioréacteur à lit fluidisé inverse utilisé pour cette étude et donc ils ont été considérés comme les produits majoritaires de stockage par les BSR. Sur cette base, un modèle mathématique a été développé, qui montre un bon compromis entre les données expérimentales et simulées, et confirme donc le rôle clé des processus d'accumulation. Afin de comprendre les voies métaboliques impliquées dans l'oxydation anaérobie du méthane couplé à la réduction des sulfates (AOM-SR), différents donneurs et accepteurs d'électrons ont été ajoutés au cours de test d'incubations in vitro visant à enrichir la communauté microbienne impliqué dans l'AOM-SR à haute pression avec plusieurs co-substrats. L'AOM-SR est stimulée par l'addition de l'acétate ce qui n'a pas été rapporté pour d'autres communautés impliqué dans l'AOM-SR. En outre, l'acétate a été généré dans le test de contrôle résultant probablement de la réduction de CO2. Ces résultats renforcent l'hypothèse que l'acétate peut servir d'intermédiaire dans le processus de l'AOM-SR, au moins pour certains groupes de archées anaérobie méthanotrophe (ANME) et les bactéries sulfato-réductrices
This work investigated two different approaches to optimize biological sulphate reduction: to develop a process control strategy to optimize the input of an electron donor and the applicability of a cheap carbon source, i.e., methane. For the design of a control strategy that uses the organic loading rate (OLR) as control input, feast and famine behaviour conditions were applied to a sulphate reducing bioreactor to excite the dynamics of the process. Such feast/famine regimes were shown to induce the accumulation of carbon, and possibly sulphur, storage compounds in the sulphate reducing biomass. This study showed that delays in the response time and a high control gain can be considered as the most critical factors affecting the application of a sulphide control strategy in bioreactors. The delays are caused by the induction of different metabolic pathways in the anaerobic sludge including the accumulation of storage products. Polyhydroxybutyrate (PHB) and sulphate were found to accumulate in the biomass present in the inversed fluidized bed used in this study, and consequently, they were considered to be the main storage compounds used by SRB. On this basis a mathematical model was developed which showed a good fit between experimental and simulated data giving further support to key role of accumulation processes. In order to understand the microbial pathways in the anaerobic oxidation of methane coupled to sulphate reduction (AOM-SR) diverse potential electron donors and acceptors were added to in vitro incubations of an AOM-SR enrichment at high pressure with several co-substrates. The AOM-SR is stimulated by the addition of acetate which has not been reported for any other AOM-SR performing communities. In addition, acetate was formed in the control group probably resulting from the reduction of CO2. These results support the hypothesis that acetate may serve as an intermediate in the AOM-SR process, at least in some groups of anaerobic methanotrophs (ANME) and sulphate reducing bacteria

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Hagenbuch, Bruno Hagenbuch Bruno Angelo. "Charakterisierung des Sulfat- und Phosphattransportes in der basolateralen Membran des Nieren- und Darmepithels der Ratte /." [S.l.] : [s.n.], 1986. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=8051.

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Mannack, Gudrun. "Taurolithocholsäure-3-sulfat beeinträchtigt die Insulin-induzierte Signaltransduktion in kultivierten Rattenhepatozyten und der perfundierten Rattenleber /." Düsseldorf, 2007. http://opac.nebis.ch/cgi-bin/showAbstract.pl?sys=000253823.

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Rehberg, Kay. "Industrielle Beeinflussung des tiefen Grundwassers durch Phenole und Sulfat in der Region Zeitz, Sachsen-Anhalt /." Leipzig ; Halle : UFZ, 2003. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=010511409&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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Luther, Markus. "Nutzung von 1-Naphthalinsulfonsäure als Schwefelquelle für die Grünlage Scenedesmus obliquus im Vergleich mit Sulfat." [S.l. : s.n.], 1988. http://www.gbv.de/dms/bs/toc/018084362.pdf.

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Rieder, Florian. "Wirkung der spezifischen Phosphodiesterase-Inhibitoren Roflumilast und Pumafentrine im Mausmodell der Dextran-Sodium-Sulfat-induzierten Kolitis." Diss., lmu, 2004. http://nbn-resolving.de/urn:nbn:de:bvb:19-28038.

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Richter, Guido. "Verlagerung von Sulfat in Böden und Ableitung von Empfehlungen zur Steuerung des Eintrags in das Grundwasser /." Leipzig ; Halle : UFZ, 2003. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=015383367&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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Gustafsson, Therése. "Effekten på nedbrytningen av rötter vid tillförsel av ammonium sulfat i en granskog i sydvästra Sverige." Thesis, Linköping University, Department of Thematic Studies, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-1422.

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Decomposition of organic matter is a critical process in the ecosystem, which involves many essential biotic and physical parts. Decomposition is therefore an important process both above and below ground. The rate of decomposition is dependent of many environmental factors for example: pH, moisture and supply of oxygen. The decomposition can therefore be affected by large scaled environmental influences, such as acidification and climatic changes. The root litter in the forest is in different ways affected by acidification, liming and manuering. Because of the important role the root system has to the whole forest ecosystem, it can be of importance to gain knowledge about how roots are affected by external environmental influences.

In the forest ecosystem fertilise the soil has become a common practice in forest management to optimise tree production. Experiments with nitrogen fertilisation have shown that the volume growths of the tree and litter supply have increased after fertilisation. There are also reports about the negative effects nitrogen fertilisation has on decomposition, which results in a decreased decomposition of organic matter.

The aim of this study is to investigate how the decomposition of organic matter, in this case roots, is affected by a large addition of ammonium sulphate. The study concentrates on to statistically evaluate important aspects on how addition of ammonium sulphate affects the decomposition of organic matter below ground in different soil layers and root diameters, and investigate the possibilities that addition of ammonium sulphate could lead to a decreasing potential of carbon mineralisation.

The study was conducted is in Skogaby, which is located in southwest Sweden in the community of Halland. Samplings of roots were made in the experimental area from the humus and mineral layer. Roots used for this study varied from less than 2mm up to 2-5mm. Decomposition of root litters were made with litterbags, which were placed in the soil in the humus and mineral layer in the original place of were the roots were collected. The results from this study showed that there appear significant differences in some of the cases between the control and ammonium sulphate treatments. The conclusion that can be drawn by this study is that the addition of ammonium sulphate, under certain conditions depending on root diameter and soil layer, comes to affect the decomposition of root litter. The addition of ammonium sulphate seems to have a positive effect on the decomposition in the initial phase, for then come to decrease in the later phases and be similar to the control areas. It can also be determined that decomposition does not seem to vary within treatments with regards to root diameter and soil layer. Regarding the question about how carbon mineralisation is affected by addition of ammonium sulphate it is probable that the addition would come to increase the mineralisation in the initial phases of the decomposition, compared with the control plots.

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Zehnder, Lara-Sophie [Verfasser]. "Die diagnostische Bedeutung des Dehydroepiandrosteron-Sulfat-Serumspiegels für den Nachweis einer zentralen Nebennierenrindeninsuffizienz / Lara-Sophie Zehnder." Tübingen : Universitätsbibliothek Tübingen, 2021. http://nbn-resolving.de/urn:nbn:de:bsz:21-dspace-1190392.

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Weißenberg, Christine [Verfasser], and Gernot [Akademischer Betreuer] Bruchelt. "Analytik von Galaktocerebrosid-3-sulfat im Urin zur Diagnostik der Metachromatischen Leukodystrophie / Christine Weißenberg ; Betreuer: Gernot Bruchelt." Tübingen : Universitätsbibliothek Tübingen, 2011. http://d-nb.info/1161464654/34.

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Noack, Jens [Verfasser], and J. [Akademischer Betreuer] Tübke. "Entwicklung eines Energiespeicherkonzeptes auf der Basis von wässrigen Vanadium(II)-sulfat-Lösungen / Jens Noack ; Betreuer: J. Tübke." Karlsruhe : KIT-Bibliothek, 2021. http://d-nb.info/1234063689/34.

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Hoefert, Norbert [Verfasser]. "Automatisierte Wasseranalyse zur Bestimmung von Calcium, Magnesium, Sulfat, Carbonat, Phosphat und Ammonium mit Hilfe potentiometrischer Titrationstechniken / Norbert Hoefert." Karlsruhe : KIT-Bibliothek, 2018. http://d-nb.info/1169212166/34.

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Maja, Milanović. "Uticaj anjonskog i nejonskog tenzida na fizičko-hemijske osobine vodenih rastvora makromolekula." Phd thesis, Univerzitet u Novom Sadu, Medicinski fakultet u Novom Sadu, 2016. http://www.cris.uns.ac.rs/record.jsf?recordId=101078&source=NDLTD&language=en.

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Razvoj savremenih sistema za ciljanu aplikaciju farmakološki aktivne supstance zasniva se na postojanju interakcija između funkcionalnih grupa makromolekula i površinski aktivne materije što omogućava kontrolisano oslobađanje, smanjenu toksičnost i bolji režim doziranja leka. Prisustvo tenzida, kako se jos površinski aktivne materije nazivaju, u niskim koncentracijima može značajno da izmeni konformaciju makromolekula i viskozitet sistema, i samim tim proširi mogućnosti primene modifikovanjem svojstava. Stoga je poznavanje fizičko-hemijskih osobina vodenih rastvora makromolekul-površinski aktivna materija neophodno radi dobijanja adekvatnog finalnog proizvoda unapređenih osobina uz primenu optimalnih koncentracija pomoćnih supstanci. U radu su prikazani rezultati ispitivanja uticaja natrijum lauril sulfata, predstavnika anjonskih tenzida, odnosno polioksietilen (20) sorbitan monooleata, kao široko korišćenog nejonskog tenzida na fizičko-hemijske osobine vodenih rastvora makromolekula karbomera 940 i ksantan gume. U cilju potpunog razumevanja ovih sistema, čiste komponente su prvo analizirane infracrvenom spektroskopijom primenom Fourierove tranformacije. Ponašanje karbomera 940 odnosno ksantan gume u prisustvu tenzida, ispitano je kombinacijom različitih tehnika (viskozimetrije, konduktometrije, tenziometrije, spektroskopije, spektrofluorimetrije, skenirajuće elektronske mikroskopije) koje pružaju uporedive rezultate. Određene vrednosti interakcionih parametara, potvrdjuju hipotezu o postojanju međudejstva između karbomera 940/ksantan gume i ispitivanih tenzida i ukazuju da povećanje koncentracije makromolekula u rastvoru uslovljava širenje opsega interakcije. Tenzidom indukovane promene konformacije ksantan gume odnosno karbomera 940 potvrđene su i na mikroskopskom nivou. Takođe, rezultati uticaja ispitivanih tenzida na osobine vodenih rastvora smeša karbomera 940 i ksantan gume dobijeni su istim tehnikama. Međudejstvom dva različita polimera bez dodatne sinteze na jeftin i brz način mogu se postići željene karakteristike sistema. Na osnovu eksperimentalnih rezultata definisani su matematički modeli primenom metodologije odzivnih površina i višestruke linearne regresije, čija je validnost statistički potvrđena te se mogu primeniti u optimizaciji i predviđanju fizičko-hemijskih osobina vodenih rastvora analiziranih binarnih sistema.
The possible interactions between polymers and surfactants are of great interest in the development of drug delivery systems, where they improve therapeutic efficiency by the controlled release and reduced toxicity. The addition of even a small amount of surfactant could change the physico-chemical properties of polymer dispersions in terms of viscosity and stability of the system and, consequently, enlarge possibilities for their application. Therefore, understanding the physico-chemical properties of polymer-surfactant aqueous solutions are necessary in order to optimize the formulation of these compounds and consequently to get product with acceptable properties and desired effect. In this thesis the physico-chemical changes of carbomer 940 and xanthan gum influenced by different surfactants were investigated. Widely used anionic surfactant sodium dodecyl sulfate, and nonionic polyoxyethylene (20) sorbitan monooleate were used. In order to completely understand the mechanism of interaction the pure polymers and surfactants were tested by Fourier transform infrared spectrometer. The behaviour of carbomer 940 as well as xanthan gum in the presence of examined surfactants were analysed by the combination of different techniques such as viscometry, conductometry, tensiometry, spectrophotometry, fluorimetry and scanning electron microscopy. The obtained results confirmed the existence of interactions between carbomer 940 / xanthan gum and tested surfactants. Furthermore, the interaction parameters were determined and the polymer saturation points for both surfactants increased with the increase in carbomer 940 and xanthan gum content, respectively. Additionally, the surfactant induced microstructural changes of carbomer 940 as well as xanthan gum were confirmed. Moreover, the physico-chemical properties of the mixture of carbomer 940 and xanthan gum influenced by the addition of anionic and nonionic surfactant were examined by the same techniques. Without additional synthesis the desired characteristics of the system could be achieved by optimizing the interaction between two different polymers. The obtained results were analysed by response surface methodology and multiple linear regression analysis. The defined mathematical models could be used to optimize and predict physico-chemical properties of aqueous solutions of the tested binary systems.

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Zittlau, Arne Henning [Verfasser], Juraj [Akademischer Betreuer] Majzlan, and Kai-Uwe [Akademischer Betreuer] Totsche. "Synthesen und kalorimetrische Studien ausgewählter Kupfer-Sulfat-, Phosphat- und Arsenatminerale / Arne Henning Zittlau. Gutachter: Juraj Majzlan ; Kai-Uwe Totsche." Jena : Thüringer Universitäts- und Landesbibliothek Jena, 2014. http://d-nb.info/1060717271/34.

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Lindemann, Jörg. "Quantifizierung biogeochemischer Eisen- und Sulfat-Umsetzungen in einem Quellmoor und deren Beitrag zur Säureneutralisierung in einem Einzugsgebiet des Frankenwaldes /." Bayreuth : Institut für Terrestrische Ökosystemforschung, 1997. http://www.gbv.de/dms/bs/toc/24076241X.pdf.

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Thöne, Lotte [Verfasser], Birgitta-C. [Akademischer Betreuer] Burckhardt, and Walter [Akademischer Betreuer] Stühmer. "Untersuchungen zur Chloridabhängigkeit des Sulfat-Anionen-Transporters 1 / Lotte Thöne. Gutachter: Birgitta-C. Burckhardt ; Walter Stühmer. Betreuer: Birgitta-C. Burckhardt." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2013. http://d-nb.info/1044306386/34.

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Sandberg, Birgersson Paulina. "Kemisk fällning av fosfor med tvåvärt järn i kombination med aktivslam eller membranbioreaktor." Thesis, KTH, Skolan för kemivetenskap (CHE), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-208341.

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Stockholm Vatten AB (SVAB) behöver utöka kapaciteten på avloppsreningsverket i Henriksdal. Därför kommer en membranbioreaktor (MBR) att implementeras i dagens befintliga aktivslamanläggning. Den nya anläggningen dimensioneras för att kunna hantera det förväntade flödet år 2040. Det framtida verket kommer dessutom behöva rena avloppsvatten som i dagsläget behandlas i verket i Bromma. Ytterligare förväntas utsläppskraven för fosfor (P), kväve (N) och organiskt material (BOD7) att skärpas. För närvarande bedriver SVAB i samarbete med IVL (Svenska miljöinstitutet) en pilotanläggning i Sjöstadsverket för att undersöka hur tekniken effektivt kan implementeras i Henriksdal. En stor utmaning för att optimera driften är reningsprocessen av fosfor. Som alternativ till efterfällning av fosfor önskar Henriksdal att simultanfälla fosfor med tvåvärt järn (Fe2+) i MBR:en. I följande arbete utreds hur kemisk fällning av fosfor med Fe2+ fungerar i kombination med aktivslam och mer specifikt, med MBR. Syftet med arbetet är att bidra med kunskap till fortsatta studier i Sjöstadsverket inför implementeringen av MBR i Henriksdal. Arbetet utreder delar inom den kunskap och forskning som finns gällande området idag och identifierar kunskapsluckor inom studiet. Fokus har bland annat legat på att beskriva; mekanismer och reaktionskinetik; utreda vilka parametrar som styr utfällningen; hur slammet och den biologiska aktiviteten påverkas; samt hur dosering av järn inverkar på MBR. Få studier har gjorts inom området och i många fall varierar resultaten studierna emellan. Detta beror sannolikt på två faktorer: 1) Vattenmatrisen i avloppsvattnet är komplex. 2) Avloppsvattnets innehåll kan variera mycket. Exakta reaktioner och mekanismer för hur fosfor avskiljs med järn(II)dosering är ännu inte fullständigt klarlagt. En stor del av Fe2+ som tillsätts kommer att oxideras till trevärt järn (Fe3+). Oxidationshastigheten av Fe2+ styrs främst av pH och syretillgänglighet i vatten och hastigheten varierar kraftigt med avseende på dessa parametrar. Fe2+ kan även oxideras biologiskt under anoxiska förhållanden av denitrifierare. Fosfor avskiljas i sin tur antingen direkt genom utfällning med Fe2+ eller Fe3+, eller genom adsorption till järnhydroxider. Järn(II)dosering inverkar på slammets morfologi, sedimenteringsindex, storlek och stabilitet. Dosering med Fe2+ ger kompakta flockar med släta och täta ytor samt få utstickande filament. Fe2+ kan inverka på den biologiska aktiviteten i slammet, men där finns bevis gällande både en synergistisk inverkan och en reducerande effekt. Generellt rekommenderas att molförhållanden över 2, Fe2+:P används för att uppnå tillräcklig avskiljning av fosfor i aktivslam. Liknande molförhållande tycks rekommenderas i MBR. Utöver doseringshalt kan även doseringspunkt inverka på både avskiljningsgraden av fosfor och nedsmutsningen av membranen. I studien sammanställdes även en massbalans av flödet och järn i MBR-linjen i Sjöstadsverket. Ytterligare gjordes analyser på vattnet för att undersöka förhållandet Vid massbalansen uppmärksammades att avskiljningen av fosfor är låg i förluftning (FL) och försedimentering (FS). Avskiljningsgraden låg under vad som förväntades (uppmätt 18 %, förväntad 50 %). Den låga avskiljningsgraden beror sannolikt på att FL och Fs är förhållandevis små. I MBR erhölls ett 40 % större uttag av järn jämfört med inkommande halt järn till MBR. Det bör kunna förklaras av att järnhalten i slammet under denna period var ovanligt hög. Förhållandet mellan fria Fe2+- och Fe3+-joner analyserades i tvåpunkter, efter FL (mätpunkt 1) och efter FS (mätpunkt 2). I mätpunkt 1 hade 80 % av järnjonerna fällt ut och ca 60 % oxiderat till trevärt järn. Uppehållstiden i FL är ca 13 min. pH mättes i hela MBR-reningslinjen. I FL och FS låg pH kring ungefär 7,5 och i MBR-reaktorerna låg pH omkring 6,5. Det förenklade hastighetsuttrycket för oxidation av järn vid syrerika förhållanden d[Fe (II)]/dt = -k􁇱[Fe(II)] användes för att beräkna den teoretiska halveringstiden (t1/2) av Fe2+. t1/2 i FL beräknades till 13 min, i FS till 22 min och i MBR-reaktorerna till omkring 2 h. Den teoretiska t1/2 stämmer relativt bra överens med vad som uppmättes vid analys av Fe2+: Fe3+. Den slutsats som kan dras är att sannolikt så kommer mer av järnet att fälla ut i sin trevärda form då järnet doseras i FL och FS, än då järnet doseras i de luftade biologiska reaktorerna. Sammanfattningsvis, finns få studier som utreder processen för utfällning av fosfor med Fe(II) i aktivslam eller MBR. Kunskapen inom området är begränsad och det finns ännu många kunskapsluckor som behöver täckas. På grund av avloppsvattnets komplexitet räcker inte teoretisk kunskap för en effektiv implementering av MBR.
To expand the capacity of the Stockholm Vatten AB (SVAB) municipal waste water treatment plant (WWTP) “Henriksdal” a membrane bioreactor will be implemented in the existing activated sludge process. The new WWTP is dimensioned to handle the expected flow of year 2040. The future WWTP will also need to treat waste water is currently treated in Bromma. Furthermore, the effluent treatment requirements for phosphorus (P), nitrogen (N) and organic substituents is expected to become stricter. In cooperation between SVAB and IVL (The Swedish Environmental Institute) the new treatment process is being tested in a pilot plant in Sjöstadsverket. One of the challenges in the new project is to achieve sufficient removal of phosphorus. Today Henriksdal WWTP removes phosphorus through post-precipitation with ferrous iron (Fe2+). When the MBR is implemented SVAB wants to use simultaneous precipitation in the MBR. In this report the chemical precipitation of Fe2+ in combination with activated sludge and MBR is examined. The aim of this thesis is to aid SVAB by contributing with knowledge in the mentioned area. The report examines the knowledge and research available about the area today and identifies if there are any gaps of knowledge. Focus of the study is among other things: the reaction mechanisms and kinetics; what parameters favor efficient precipitation; how does ferrous iron integrate with the sludge; how to efficiently combine ferrous iron precipitation in MBR. There are only a few studies in the field and the results often contradict each other. It is likely due to two factors: 1) the matrix of waste water is complex. 2) the matrix varies considerably between different areas and different WWTP’s. The exact mechanisms and kinetics of phosphorus removal with chemical precipitation of ferrous iron are not fully understood. A lot of the Fe2+ will oxidize to ferric iron (Fe3+). The oxidation rate is mainly dependent on the pH and oxygen concentration in the water. Fe2+ can also be oxidized through biological oxidation in anoxic environments. The phosphorus is removed by direct precipitation with Fe2+ and Fe3+, or through adsorption to iron hydroxides. Fe2+ can influence the characteristics of the sludge by changing the morphology, the size and the stability of the flocs and the settleability of the sludge. Dosing Fe2+ gives more compact flocs, with smooth surfaces and few filaments. Fe2+ can also influence the biological activity in the sludge. Some studies states the iron contributes to synergistic effects, some claim it reduces the activity. For efficient phosphorus removal in activated sludge ratios of Fe:P > 2 mole /mole is mostly used. The recommendations seem to be the same for MBR. The dosing point also seem to be of importance to achieve sufficient removal, and furthermore to prevent fouling of the membranes. Material balances for phosphorous and for iron, as well as analyses to examine the oxidation rate and pH of the waste water in the MBR-pilot plant were also performed. The material balance showed that the removal of phosphorous in the pre-aeration (PA) and the pre-sedimentation (PS) was low. The expected removal was 50 % while the achieved removal 18 %. This is probably due to the relatively small size of the PA and PS compared to the rest of the pilot-plant. In the MBR the outgoing flow of iron was 40 % larger than the incoming flow. During the examined weeks the iron concentration in the sludge was higher than usually. Probably iron had been accumulated in the sludge the weeks before. The ratio between Fe2+-ions and Fe3+-ions was analyzed in two points, in the flow following the PA respectively the flow following the PS. In the PA 80 % of the ions had precipitated and 60 % of the free irons had been oxidized to Fe3+. pH was measured in each reactor of the pilot plant. In the PA and the PS the pH was about 7.5, while in the MBR-reactors the pH was around 6.5. The theoretical half-life (t1/2) of Fe2+ was calculated from a simplified rate reaction expression for oxidation of Fe2+ in aerated waters. t1/2 in the PA was around 13 minutes, in the PS around 22 minutes and the bio reactors around 2h. The theoretical t1/2 of Fe2+ is relatively close to the measured values of the ratio between Fe2+-ions and Fe3+-ions. From the results of the studies it is likely that more of the iron will precipitate as ferric iron in the PA and PS than if the ferrous iron is dosed in the aerated bioreactors. In conclusion: there are only very few studies that examines the precipitation process of ferrous iron in activated sludge or MBR. The theoretical knowledge is not wide enough to use as an only tool when MBR is implanted in new WWTP’s. Due to the complexity of the waste water empirical studies need to be performed under the actual conditions that prevail at Henriksdal WWTP.

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Bauer, Christian. "Der Interleukin-1β-converting-enzyme-Inhibitor Pralnacasan reduziert die Dextran-Sulfat-Sodium-induzierte Kolitis und die IL-18-vermittelte Th1-Zell-Aktivierung." Diss., lmu, 2006. http://nbn-resolving.de/urn:nbn:de:bvb:19-53661.

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29

Gratzl, Susanna [Verfasser], and Robert H. G. [Akademischer Betreuer] Schwinger. "Untersuchung der Wirkung einer intravenösen Therapie mit Magnesium-Sulfat auf die Konversionsrate bei neu aufgetretenem Vorhofflimmern / Susanna Gratzl ; Betreuer: Robert H.G. Schwinger." Regensburg : Universitätsbibliothek Regensburg, 2018. http://d-nb.info/1156008271/34.

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30

Schoeps, Maria, and Josefin Andersson. "The 200-year history of nss-SO42- concentration in snow and ice from Lomonosovfonna, Svalbard." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-255691.

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Environmental scientists use ice-core records to reconstruct past atmospheric conditions. Anthropogenic and natural sources of emissions can be traced when analyzing ions in the ice, which is included in the science of glaciochemistry. Sulfate is an excellent ion to use in these studies since it is traceable to these emissions. This study is therefore focused on the sulfate ion, how its concentration has fluctuated over the last 200-years and when a change of trend occurred. The ice-cores used in this study were extracted at Lomonosovfonna, Svalbard, and analyzed by Ion Chromatography (IC). The new data that has been brought forth in this study covers nss-SO42- concentrations in the years of 1998-2012 and is connected to previous extracted ice-core records. The results of nss-SO42- concentration in the ice-cores confirm the change of trend in the 1970s. The increasing trend in the result correlate with historical emissions and the decrease after the change of trend enhances less anthropogenic impact on the atmosphere.
Miljöforskare använder sig av isborrkärnor för att återskapa tidigare atmosfäriska förhållanden. Antropogena och naturliga utsläppskällor kan spåras genom att analysera joner i isen. Sulfat är en utmärkt jon att använda sig av i dessa studier, eftersom den kan anknytas till dessa utsläpp. Denna studie fokuserar därför på sulfatjonen, hur dess koncentration har ändrats under de senaste 200-åren och på det trendbrott som har ägt rum. Isborrkärnorna som har använts i denna studie borrades upp på Lomonosovfonna, Svalbard, och analyserades med jonkromato-grafi. Ny data som har tagits fram i den här studien täcker nss-SO42- koncentrationen mellan 1998-2012 och är sammankopplad med tidigare framtagen data från samma plats. Resultatet av nss-SO42- koncentrationen i isborrkärnorna bekräftar trendbrottet som inträffade på 1970-talet. Den ökande trenden i resultatet korrelerar med historiska utsläpp och minskningen efter trendbrottet påvisar mindre antropogen påverkan på atmosfären.

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31

Yao, Jun. "Untersuchungen zum Einfluss von Sauerstoff, Nitrat und Sulfat sowie Wasserstoffperoxid auf Bioverfügbarkeit und Bioremediation bei PAK-Bodenkontamination mit In-situ-Anwendung auf einem Gaswerksgelände." [S.l.] : [s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=963032569.

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32

Schulz, Joachim Günther. "Identifikation des Glykosylphosphatidylinositol-verankerten Heparan Sulfat Proteoglykans Glypikan als Toxizitäts-vermittelndem Rezeptor für Beta-Amyloid der Alzheimer´schen Krankheit in der neuronalen PC12 Zellinie." Doctoral thesis, Humboldt-Universität zu Berlin, Medizinische Fakultät - Universitätsklinikum Charité, 1998. http://dx.doi.org/10.18452/14407.

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In der vorliegenden Arbeit konnte mit der PC12 Zellinie und dem MTT Viabilitätsassay Glypikan, ein Glykosylphosphatidylinositol-verankertes Heparan Sulfat, als Rezeptor identifiziert werden, der die toxischen Effekte von [beta]-Amyloid vermittelt. Kompetitive Substanzen im Medium, enzymatische Behandlung der Zelloberfläche und Block spezifischer zellulärer Synthesewege wurden eingesetzt. [beta]-Amyloid wird eine zentrale Rolle in der Pathogenese der Alzheimer'schen Krankheit zugeschrieben. Eine Intervention auf Ebene der [beta]-Amyloid-Rezeptor Interaktion könnte einen Therapieansatz für die Alzheimer'sche Krankheit darstellen. Weitere Experimente sind notwendig, um die Rolle von Glypikan bei der Vermittlung der [beta]-Amyloid Toxizität im Alzheimer-Gehirn zu untersuchen, z.B. in der Primärkultur von Neuronen und Mikroglia oder im lebenden Hirnschnitt. Eine ähnliche anatomische Verteilung der Glypikanexpression im Rattenhirn und der neurofibrillären Bündel im Alzheimergehirn wurde gefunden. Eine mögliche Rolle für Glypikan bei der Entstehung der neurofibrillären Bündel muß im Autopsiegehirn von Alzheimerpatienten überprüft werden.
[beta]-amyloid is thought to play a major role in the pathogenesis of Alzheimer's disease. In PC12 cell culture, competitive substances in cell culture medium, enzymatic cell surface treatment und block of specific cell synthesis pathways were used to identify glypican, a GPI- anchored heparan sulfate proteoglycan, as a receptor that mediates the toxic effects of [beta]-amyloid.

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33

Sanches, Carlos Vinícius [UNESP]. "Disponibilidade de Ni em um latossolo vermelho distrófico em função da aplicação de gesso agrícola e caracterização fisiológica e bioquímica do algodoeiro." Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/151924.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O algodoeiro apresenta uma sensibilidade elevada nos sistemas de cultivo. A acidez do solo aliada a alta concentração alumínio e a baixa disponibilidade de cálcio em profundidade podem limitar a produtividade sendo possível verificar distúrbios nutricionais. Nesse contexto, o níquel, nutriente essencial, componente da metaloenzima urease tem sua importância comprovada no metabolismo do nitrogênio e vem sendo estudado como alternativa para melhorar a qualidade do sistema de cultivo por meio da eficiência do uso do nitrogênio disponível. Outra vertente de estudos diz respeito a capacidade do níquel de agir como metal pesado sendo prejudicial para as culturas, dessa maneira faz-se necessário entender a dinâmica desse nutriente dentro dos sistemas de cultivo. Tendo em vista o exposto, o objetivo deste trabalho foi verificar os efeitos da aplicação de diferentes doses de níquel e gesso, e a interação entre os dois sobre o crescimento, produtividade e estado nutricional de plantas de algodoeiro em condições de campo. O experimento foi desenvolvido em dois anos, os tratamentos utilizados foram 0,0; 1,0; 2,0; 6,0; 12 e 16 kg ha-1 de Ni e 0, 200, 400 e 800 kg ha-1 de gesso, aplicados via solo. Utilizou-se o delineamento em blocos ao acaso em um fatorial 6x4 com 3 repetições. Para mensurar o efeito dos tratamentos, os parâmetros de crescimento (altura, diâmetro e número de ramos), estado nutricional (P, K, Ca, Mg, S, Cu, Fe, Mn, Zn e Ni), e produtividade (número de estruturas reprodutivas, produtividade de algodão em caroço, rendimento de fibra e massa de 20 capulhos), foram submetidos a análise de variância e regressão polinomial por meio do software de análise estatística Sisvar 5.1. Há variações na produtividade em função das condições climáticas, em déficit hídrico severo foi possível concluir que o aumento na dose de gesso pode reduzir a produtividade do algodoeiro linearmente, a aplicação de doses de níquel e gesso, nas condições apresentadas nesse experimento, não exercem influência no crescimento e desenvolvimento do algodoeiro. O fornecimento de gesso até 800 kg/ha interfere na absorção de Ni, verifica-se um antagonismo entre cálcio e níquel. O fornecimento de níquel via solo não interfere na absorção de nutrientes com exceção do cálcio. O cálcio exerce antagonismo em relação ao manganês. As doses de níquel não promoveram efeitos positivos ou negativos no crescimento e desenvolvimento do algodoeiro.
The cotton plant has a high sensitivity in the cropping systems. The soil acidity allied to high aluminum concentration and low calcium availability in depth may limit the productivity and develop nutritional disorders. In this context, nickel, essential element, component of metalloenzyme urease, has its importance proven in the nitrogen metabolism. It has been studied as an alternative to improve the cropping system quality through an efficient use of the available nitrogen. Another strand of studies mentions about the nickel capacity to act as a heavy metal and being harmful to the crops, thereby making it necessary to understand this nutrient dynamic within the cropping systems. Based on the foregoing, the objective of this study was to verify the effects of the application of different nickel and gypsum doses, and the interaction between them on the growth, crop yield and nutritional status of cotton plants under field conditions. The experiment was conducted in two years, the treatments used were 0,0; 1,0; 2,0; 6,0; 12 and 16 kg ha-1 of Ni and 0, 200, 400 and 800 kg ha-1 of gypsum, applied via soil. A randomized complete block design was used in a 6x4 factorial scheme with 3 repetitions. In order to measure the treatment effects, the parameters of growth (high, diameter and number of branches), nutritional status (P, K, Ca, Mg, S, Cu, Fe, Mn, Zn and Ni), and crop yield (number of reproductive structures, seed cotton yield, fiber cotton yield and mass of 20 cotton bolls), were submitted to an analysis of variance and polynomial regression through a software of statistical analysis Sisvar 5.1. There are variations in the crop yield in function of the climate conditions; in severe water deficit, it was possible to conclude that the increase in gypsum doses can reduce cotton crop yield linearly. The application of doses of nickel and gypsum, under the conditions presented, do not influence the growth and development of the cotton plants. The supply of gypsum up to 800 kg ha-1 interfere in the absorption of Ni, verifying an antagonism between calcium and nickel. The supply of nickel via soil do not interfere in the nutrients absorption with exception of calcium, which exerts antagonism over manganese. The doses of nickel did not promote positive or negatives effects in the growth and development of the cotton plants.

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34

Souza, Rui Barbosa de. "Suscetibilidade de pastas de cimento ao ataque por sulfatos - método de ensaio acelerado." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/3/3146/tde-07122006-173150/.

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O presente trabalho tem por objetivo investigar e propor uma metodologia rápida e eficaz de avaliação da reatividade do cimento Portland frente ao ataque por sulfatos. O método consiste na utilização de amostras de pasta de cimento hidratada em pó, colocadas em contato direto com soluções concentradas de Na2SO4 e MgSO4, em temperatura elevada (65ºC), para acelerar o ataque. Apesar dos cimentos estudados possuírem composição química parecida, os resultados de SO3 combinado mostraram que o cimento Classe G foi pouco menos suscetível ao ataque por sulfatos em função do maior teor de Fe2O3 presente. Da TG e DRX observou-se a formação de etringita no ataque por ambos os sais de sulfato; e formação de gipsita no ataque por MgSO4. Enquanto havia disponibilidade de portlandita na pasta hidratada, o cimento com adição mineral incorporada apresentou mesma taxa de ataque que os demais (sem adição), entretanto a partir do momento que toda a portlandita foi consumida, iniciou-se um processo de descalcificação do C-S-H, observado pela DRX.
The main point of this research is to propose a fast and effective method of evaluation of the cement reactivity to sulfate attack. Resistance to sulfate attack was measured by determining the combined sulfate in cement paste samples with exposure to Na2SO4 and MgSO4 solution, at high temperature (65°C). The samples of cement paste was triturated (powdered) in the proposed method. The results of combined SO3 showed that the Class G cement was little less susceptible to the sulfate attack because it has larger amount of Fe2O3. The ettringite formation was observed in the attack for both sulfate salts; and gypsum formation in the attack for MgSO4 (results of TG and XRD). The blended cement presented same results that the others, however when the Ca(OH)2 was totally consumed, it observed the decalcification of the C-S-H, by XRD.

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35

Batke, Monika. "Metabolismus von alkylierten polyzyklischen aromatischen Kohlenwasserstoffen : Einfluss der Struktur auf benzylische Hydroxylierung und Sulfonierung in vitro und Modulation des Metabolismus in vivo." Phd thesis, Universität Potsdam, 2008. http://opus.kobv.de/ubp/volltexte/2008/2693/.

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Die Toxizität und Kanzerogenität von rein aromatischen polyzyklischen aromatischen Kohlenwasserstoffen (PAK) ist seit Jahrzehnten bekannt und umfassend erforscht. Die alkylierten PAK (alkPAK) besitzen jedoch aufgrund ihrer Alkylgruppe eine weitere Möglichkeit zur Bioaktivierung und müssen daher gesondert betrachtet werden. Die Alkylgruppe wird zunächst hydroxyliert, anschließend zur Säure oxidiert oder direkt konjugiert. Entstehen hierbei instabile benzylische Sulfokonjugate, so können diese DNA-Addukte bilden und zu Mutationen führen. In Hinblick auf die Bioaktivierung von alkPAK galt es daher zu klären welchen Einfluss die Struktur auf die benzylische Hydroxylierung hat und welche humanen Formen der löslichen Sulfotransferasen besonders an der Umsetzung der alkPAK-Derivate beteiligt sind. Die Untersuchung der Albuminbindung von Schwefelsäureestern sowie ihre Aufnahme in Nierenzellen sollten Aufschluss hinsichtlich möglicher Transportvorgänge geben. Für die in-vivo-Situation wurde weiterhin die Modulation des Metabolismus ausgewählter benzylischer Alkohole durch verschiedene Nahrungsmittelbestandteile, Arzneimittel und Fremdstoffe an Ratten untersucht. Als Biomarker wurden benzylische Carbonsäuren im Urin und die entsprechenden Mercaptursäuren in Urin und Fäzes betrachtet. Zunächst wurde anhand von Inkubationen mit Rattenlebermikrosomen festgestellt, dass insbesondere größere Ringsystemen wie etwa alkylierte Benzo[a]pyrene im Gegensatz zu Methylpyrenen in wesentlich geringerem Umfang zum benzylischen Alkohol umgesetzt werden. Dies wurde auch in Untersuchungen mit humanen Lebermikrosomen bestätigt. Untersuchungen an einzelnen humanen Cytochromen P450 zeigten, dass insbesondere die durch PAK induzierbaren Formen hCYP1A1 und 1B1 hohe Umsatzraten aufwiesen. Die hepatisch exprimierten Formen hCYP1A2 und 3A4 waren jedoch auch zur Bildung der benzylischen Alkohole in der Lage. Für die anschließende Sulfonierung der benzylischen Alkohole wurden besonders hohe Aktivitäten mit den humanen Sulfotransferasen hSULT1A1, 1A2, 1C2 und 1E1 festgestellt. Aufgrund der Enzymexpression und der guten Durchblutung, die eine gute Substratversorgung ermöglicht, ist die Leber als Hauptort der benzylischen Hydroxylierung und Sulfonierung anzusehen. Ergebnisse unserer Arbeitsgruppe zeigen jedoch, dass nach 1-Hydroxymethylpyren-Applikation bei Ratten die Niere die höchste Zahl an DNA-Addukten aufweist. Wegen der Fokussierung der Sulfonierung auf die Leber ist die systemische Verteilung der Schwefelsäureester die einzig plausible Erklärung. So wurde im Rahmen dieser Arbeit eine hochaffine Bindungsstelle für 2-Sulfoxymethylpyren an Albumin beschrieben und die Aufnahme von benzylischen Sulfaten durch die humanen organischen Anionentransporter hOAT1, 3 und 4 in Nierenzellen in vitro gezeigt. Für die in-vivo-Situation wurde der Einfluss von Ethanol, 4-Methylpyrazol, Pentachlorphenol, Quercetin und Disulfiram untersucht. Neben der durch die Detoxifizierung mittels Alkoholdehydrogenase und Aldehyddehydrogenase entstandenen benzylischen Carbonsäure kann als Biomarker die entsprechende Mercaptursäure herangezogen werden. Sie ist ein indirekter Nachweis für die reaktiven und toxischen benzylischen Sulfate der alkPAK. Für die beiden im Tierversuch eingesetzten benzylischen Alkohole (1-Hydroxymethylpyren und 1-Hydroxymethyl-8-methylpyren) konnte sie in Urin und Fäzes nachgewiesen werden. Es wurde jedoch ein deutlicher Unterschied in der gebildeten Menge sowie der Verteilung zwischen Urin und Fäzes für die beiden Mercaptursäuren festgestellt. Hierfür sind wahrscheinlich Unterschiede im Transport der benzylischen Schwefelsäureester sowie der Spezifität der an der Mercaptursäurebildung beteiligten Enzyme verantwortlich. In diesem Zusammenhang konnte gezeigt werden, dass der humane organische Anionentransporter hOAT1 1,8-Dimethylpyrenmercaptursäure nicht und der hOAT3 nur mit niedrigen Umsatzraten transportiert. Bei den Modulatoren zeigte die Gabe der kompetitiven Alkoholdehydrogenase-Hemmstoffe Ethanol und 4-Methylpyrazol die Bedeutung der Alkoholdehydrogenasen für die Entgiftung der benzylischen Alkohole: Die Oxidation zur entsprechenden Carbonsäure war reduziert und die Bildung der Mercaptursäure erhöht. Eine Hemmung der Toxifizierung vermittelt durch Sulfotransferase-Inhibitoren konnte nur für Pentachlorphenol beim Metabolismus des 1-Hydroxymethylpyrens beobachtet werden. Gleichzeitig erwies sich Pentachlorphenol als kompetitiver Alkoholdehydrogenase-Inhibitor, da eine signifikant geminderte Carbonsäureausscheidung zu beobachten war. Bei 1-Hydroxymethyl-8-methylpyren traten diese Effekte nicht auf. Die unterschiedlichen bzw. unterschiedlich starken Effekte der Modulatoren beim Metabolismus der verschiedenen benzylischen Alkohole bestätigen die Beobachtungen aus den in-vitro-Untersuchungen, dass unterschiedliche Enzym- und Transporteraffinitäten und –aktivitäten vorliegen.
The toxicity and carcinogenicity of purely aromatic polycyclic aromatic hydrocarbons (PAH) is known since decades and has been thoroughly investigated. Compared to the purely aromatic PAH the alcylated PAH (alcPAH) can additionally be biologically activated because of their alcyl group. The alcyl group is hydroxylated and subsequently oxidised to the corresponding acid or conjugated. If unstable benzylic sulfoconjugates arrise from this bioactivation DNA adducts may be formed and could induce mutations. Concering the bioactivation of alcPAH this work should help to get to know which influence the structure has on the benzylic hydroxylation and it should be clarified which forms of human soluble sulfotransferases catalyse the sulfonation of benzylic alcohols. Furthermore the albumin binding of sulfuric acid esters and the uptake into kidney cells by human organic anion transporters in vitro have been analysed to get inside into transport processes. For the in vivo situation the modulation of enzyme activities by food compounds, pharmaceuticals and xenobiotics is of interest. As biomarkers the respective benzylic carboxylic acid and mercapturic acid were measured in urine only and feces. By the use of incubations with rat liver microsomes it turned out that larger ring systems were benzylically hydroxylated to a remarkable less extent then alcyl pyrenes. This observation was also made for human liver microsomes. In vitro experiments addressing the activity of single human cytochromes P450 revealed that PAH inducable forms hCYP1A1 and 1B1 had highest hydroxylation rates, but also the hepatically expressed forms hCYP3A4 and CYP1A2 catalysed the benzylic hydroxylation. The subsequently following sulfonation of the benzylic alcohols was found to be catalysed with high formation rates by human sulfotransferase hSULT1A1, 1A2, 1C2 and 1E1. Due to the enzyme expression and the high blood circluation ensuring the substrate supply it can be assumed that liver is the main organ for benzylic hydroxylation and sulfonation. Nevertheless results from our group showed that after 1-hydroxy methyl pyrene exposure, rats had higher levels of DNA adducts in kidneys than in liver. Thus, it has to be assumed that the sulfuric acid esters are systemically distributed. In the course of this work a high affinity albumin binding site for 2-sulfoxy methyl pyrene was identified and the uptake of sulfuric acid esters mediated by human organic anion tranporter 1, 3 and 4 to kidneys cells in vitro was shown. For the further estimation of the in vivo bioactivation of alcPAH the modulation of enzyme activities by ethanol, 4-methylpyrazole, quercetin, pentachlorophenol and disulfiram was explored. The carboxylic acids formed via alcohol dehydrogenase and aldehyde dehydrogenase were used as biomarkers as well as the respective mercapturic acids. The occurence of the mercapturic acids is an indirect proof for the reactive and toxic benzylic sulfo conjugates. In the urine and fecal samples of rats treated with either 1-hydroxymethyl pyrene or 1-hydroxymethyl 8-methyl pyrene the corresponding mercapturic acids of the sulfuric acid esters were found. Even though the absolute amount excreted and the distribution in urine and fecal samples were quite different. This observation may be explained by differences in transport of the sulfuric acid esters as well as by different specificities of the enzymes responsable for mercapturic acid formation. Additionally it was shown that the human organic anion transporter 1 does not transport 1,8-dimethyl pyrenyl mercapturic acid and the human organic anion transporter 3 only with very little turnover. Whereas 1-methyl pyrenyl mercapturic acid was well transported by both of these proteins. With regard to the modulation the concurrent application of ethanol or 4-methyl pyrazole to rats revealed the important role of alcohol dehydrogenase for the detoxification of benzylic alcohols: The oxidation leading to the corresponding carboxylic acid was remarkably reduced and the excretion of the mercapturic acid via urine and feces was enhanced. In order to observe an inhibition of sulfotransferases pentachlorophenol and quercetine were concurrently applied to rats. An inhibitory effect by the means of an reduced excretion of mercapturic acid was only observed for pentachlorophenol in animals treated with 1-hydroxymethyl pyrene. In addition it turned out, that pentachlorophenol was a potent competitive alcohol dehydrogenase inhibitor as the renal excretion of the corresponding carboxylic acid was remarkably reduced. For 1-hydroxymethyl 8-methyl pyrene this modulation was not observed. These differences in effects and strenght of effects may be ascribed to different enzymatic and transport affinities and activities which have already been observed in in vitro experiments.

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36

Sanches, Carlos Vinícius. "Disponibilidade de Ni em um latossolo vermelho distrófico em função da aplicação de gesso agrícola e caracterização fisiológica e bioquímica do algodoeiro /." Ilha Solteira, 2017. http://hdl.handle.net/11449/151924.

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Orientador: Enes Furlani Junior
Resumo: O algodoeiro apresenta uma sensibilidade elevada nos sistemas de cultivo. A acidez do solo aliada a alta concentração alumínio e a baixa disponibilidade de cálcio em profundidade podem limitar a produtividade sendo possível verificar distúrbios nutricionais. Nesse contexto, o níquel, nutriente essencial, componente da metaloenzima urease tem sua importância comprovada no metabolismo do nitrogênio e vem sendo estudado como alternativa para melhorar a qualidade do sistema de cultivo por meio da eficiência do uso do nitrogênio disponível. Outra vertente de estudos diz respeito a capacidade do níquel de agir como metal pesado sendo prejudicial para as culturas, dessa maneira faz-se necessário entender a dinâmica desse nutriente dentro dos sistemas de cultivo. Tendo em vista o exposto, o objetivo deste trabalho foi verificar os efeitos da aplicação de diferentes doses de níquel e gesso, e a interação entre os dois sobre o crescimento, produtividade e estado nutricional de plantas de algodoeiro em condições de campo. O experimento foi desenvolvido em dois anos, os tratamentos utilizados foram 0,0; 1,0; 2,0; 6,0; 12 e 16 kg ha-1 de Ni e 0, 200, 400 e 800 kg ha-1 de gesso, aplicados via solo. Utilizou-se o delineamento em blocos ao acaso em um fatorial 6x4 com 3 repetições. Para mensurar o efeito dos tratamentos, os parâmetros de crescimento (altura, diâmetro e número de ramos), estado nutricional (P, K, Ca, Mg, S, Cu, Fe, Mn, Zn e Ni), e produtividade (número de estruturas reproduti... (Resumo completo, clicar acesso eletrônico abaixo)
Mestre

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37

Reyes, Alvarado Luis. "Optimization of the electron donor supply to sulphate reducing bioreactors treating inorganic wastewater." Thesis, Paris Est, 2016. http://www.theses.fr/2016PESC1151/document.

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Une grande quantité des eaux usées, particulièrement celles provenant de l'industrie minière, des fermentations et du traitement des aliments, contiennent-elles des concentrations élevées de sulfate (SO42-). SO42- réduction est une problématique sérieuse au niveau environnemental sous conditions qui ne sont pas contrôlées, cette problématique peut résulter en la libération de sulfure toxique vers l'environnement. Les caractéristiques typiques des eaux usées riches en SO42- sont 0.4-20.8 g SO42-.L-1, faible pH, élevé potentiel oxydatif, faible o négligeable demande chimique d'oxygène (DCO) et hautes concentrations de métaux lourds (drainage minier acide) que peuvent drastiquement endommager la flore et la faune des masses d'eau. L'objectif de cette thèse est d'étudier l'effet du donneur d'électrons sur le processus biologique RS par des bactéries réductrices de sulfate dans des bioréacteurs. Le processus biologique RS a été étudié à l'aide de polymères à base d'hydrate de carbone (PBHC) et biodéchets lignocellulosiques (L) comme des donneurs de libération lente d'électrons (PBCH-DLLE et L-DLLE, respectivement) dans des bioréacteurs discontinus et des bioréacteurs fonctionnant en continu inverse à lit fluidisé (ILF). Les ILF ont été rigoureusement testé pour RS sous haute vitesse et (alimentation-pénurie de nourriture) des conditions d'alimentation transitoires. Dans une autre configuration du bioréacteur, un bioréacteur séquentiel, l'effet de la concentration initiale SO42- sur le démarrage du réacteur a été étudié. Par ailleurs, l'effet de la concentration initiale du donneur d'électrons, NH4+ et SO42- ont été évalués dans des bioréacteurs de traitement par lots aussi bien. La robustesse et la résilience de RS a été démontrée dans les ILF en utilisant le lactate comme donneur d'électrons, dans lequel l'efficacité d'élimination de SO42- (EES) était comparable dans la période d’alimentation (67 ± 15%) de ILF2 aux conditions d'alimentation stables (71 ± 4%) dans même ILF2 et ILF1, le réacteur de commande (61 ± 15%). De la modélisation des réseaux de neurones artificiels et de l'analyse de sensibilité des données de fonctionnement de ILF2, il était prévu que les concentrations de SO42- influents ont affecté le rendement d'élimination de la DCO, la production de sulfure et des changements de pH. Dans un autre ILF3 à un rapport DCO:SO42- de 2.3, RS dans des conditions de taux élevés (CTE = 0.125 d) était 4,866 mg SO42- L-1 d-1 et un EES de 79% a été remporté. Par ailleurs, le second ordre Grau et les modèles d'enlèvement de substrat Stover-Kincannon équipés de la performance du réacteur à haut débit avec r2 > 0.96. Le rapport DCO:SO42- était le principal facteur affectant la RS. Dans des bioréacteurs par lots, en utilisant du papier filtre PBCH-DLLE, la RS a été réalisée à EES > 98%. Avec l'utilisation de scourer comme L-DLLE, un EES de 95% a été remporté. Cependant, lorsque la lavette est utilisée comme matériau de support de L-DLLE dans un ILF4, le RS a montré 38% (± 14) de EES entre 10-33 d de fonctionnement. La SR était limitée par le taux d'hydrolyse-fermentation et, par conséquent, la complexité de la DLLE. L'utilisation du donneur d'électrons pour le processus RS a simultanément amélioré aux concentrations de donneurs d'électrons initial décroissants
Many industrial wastewaters, particularly from the mining, fermentation and food processing industry contain high sulphate (SO42-) concentrations. SO42- reduction (SR) is a serious environmental problem under non-controlled conditions, which can result in the release of toxic sulphide to the environment. Typical characteristics of SO42--rich wastewater are 0.4-20.8 g SO42-.L-1, low pH, high oxidative potential, low or negligible chemical oxygen demand (COD) and high heavy metals concentrations (acid mine drainage), that can dramatically damage the flora and fauna of water bodies. The aim of this PhD is to study the effect of electron donor supply on the biological SR process by sulphate reducing bacteria in bioreactors. The biological SR process was studied using carbohydrate based polymers (CBP) and lignocelulosic biowaste (L) as slow release electron donors (CBP-SRED and L-SRED, respectively) in batch bioreactors and continuously operated inverse fluidized bed bioreactors (IFBB). IFBB were vigorously tested for SR under high rate and transient (feast-famine) feeding conditions. In another bioreactor configuration, a sequencing batch bioreactor, the effect of the initial SO42- concentration on the reactor start-up was investigated. Besides, the effect of the initial concentration of electron donor, NH4+, and SO42- were evaluated in batch bioreactors as well. The robustness and resilience of SR was demonstrated in IFBB using lactate as the electron donor wherein the SO42- removal efficiency (SRE) was comparable in the feast period (67 ± 15%) of IFBB2 to steady feeding conditions (71 ± 4%) in the same IFBB2 and to IFBB1, the control reactor (61 ± 15%). From artificial neural network modeling and sensitivity analysis of data of IFBB2 operation, it was envisaged that the influent SO42- concentrations affected the COD removal efficiency, the sulphide production and pH changes. In another IFBB3 at a COD:SO42- ratio of 2.3, SR under high rate conditions (HRT=0.125 d) was 4,866 mg SO42-. L-1 d-1 and a SRE of 79% was achieved. Besides, the Grau second order and the Stover-Kincannon substrate removal models fitted the high rate reactor performance with r2 > 0.96. The COD:SO42- ratio was the major factor affecting the SR. In batch bioreactors, using filter paper as CBP-SRED, SR was carried out at > 98% SRE. Using scourer as L-SRED, a 95% SRE was achieved. However, when the scourer was used as the L-SRED carrier material in an IFBB4, the SR showed 38 (± 14) % SRE between 10-33 d of operation. The SR was limited by the hydrolysis-fermentation rate and, therefore, the complexity of the SRED. Concerning sequencing batch bioreactor operation, the SR process was affected by the initial SO42- concentration (2.5 g SO42-.L-1) during the start-up. The sequencing batch bioreactor performing at low SRE (< 70%) lead to propionate accumulation, however, acetate was the major end product when SRE was > 90%. In batch bioreactors, the NH4+ feast or famine conditions affected the SR rates with only 4% and the electron donor uptake was 16.6% greater under NH4+ feast conditions. The electron donor utilization via the SR process improved simultaneously to the decreasing initial electron donor concentrations. This PhD research demonstrated that the SR process is robust to transient and high rate feeding conditions. Moreover, SR was mainly affected by the approach how electron donor is supplied, e.g. as SRED or as easy available electron donor, independently of the COD:SO42- ratio. Besides, the electron donor and SO42- utilization were affected by the lack or presence of nutrients like NH4+

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38

Teixé, Ferran Trinidad. "Expressió i funció de Sindecà-2 en limfòcits TCD4+humans." Doctoral thesis, Universitat de Barcelona, 2010. http://hdl.handle.net/10803/847.

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Els sindecans s'uneixen a molècules d'adhesió cel·lular, factors de creixement i poden actuar com a correceptors, i d'aquesta manera poden modular la funció leucocitària. En la present tesi s'ha analitzat l'expressió de sindecans en cèl·lules T CD4 primàries humanes. Per l'esmentat estudi s'han produït anticossos monoclonals contra sindecà-2.

S'ha demostrat que, en cèl·lules T CD4 humanes, l'estimulació cel·lular incrementa notablement la quantitat de sindecà-4, i de manera menys notòria també la de sindecà-2. L'expressió de sindecà-2 i sindecà-4 segueix diferents cinètiques d'inducció. Mentre que l'expressió de sindecà-4 és més ràpida i significant, la de sindecà-2 és més tardana i de vida més curta de manera que disminueix la seva expressió d'mRNA a dia 4 d'activació. Aquesta expressió de sindecà-2 i sindecà-4 és aparent tant a nivell d'mRNA com a nivell de proteïna. Els sindecans -2 i -4 s'expressen tant en cèl·lules T CD4 verges (CD45RA+) com en cèl·lules T CD4 memòria (CD45RA-).

A nivell funcional, els sindecans -2 i -4 són capaços d'aturar l'activació de la cèl·lula T tant a nivell de proliferació com a nivell de producció de citocines. S'ha demostrat experimentalment que quan s'incuben limfòcits de sang perifèrica amb anticòs anti-sindecà-4 en una reacció limfocitària mixta, decreix la proliferació de les cèl·lules T, però aquest fenomen no s'ha observat al incubar les cèl·lules amb anticòs anti-sindecà-2. Tanmateix, l'entrecreuament de sindecà-2 o sindecà-4 en T CD4 mitjançant anticossos, bloqueja la proliferació cel·lular i redueix la producció de TNF de les cèl·lules T en presència de concentracions òptimes d'anticòs contra CD3.
Aquests resultats suggereixen que sindecà-2 i sindecà-4 podrien actuar com a inhibidors de l'activació de la cèl·lula T. La disminució de la proliferació està causada per un bloqueig en el cicle cel·lular. L'entrecreuament de l'anticòs contra sindecà-2 amb les cèl·lules T en presència d'anticòs anti-CD3 causa també una inhibició de la producció de les citocines IL-2, IL-10, TNF i TGFbeta. De manera que es veuen compromesos els dos principals fenòmens que desencadenen l'activació de la cèl·lula T: la proliferació i la producció de citocines.
Aquesta inhibició també s'ha observat en cèl·lules Jurkat que sobreexpressen sindecà-2.
També s'ha investigat el paper que juguen les vies de senyalització de les MAPK en el control de l'expressió de sindecà-2 en cèl·lules T. S'ha demostrat que la producció de sindecà-2, però no la de sindecà-4, requereix la senyalització de la MAPK p38 alfa/beta en cèl·lules T CD4.

D'altra banda, s'ha estudiat la senyalització induïda per sindecà-2 en cèl·lules T i s'ha observat que l'entrecreuament de les cèl·lules T CD4 amb anticòs anti-sindecà-2 promou la fosforilació d'una proteïna que presumptament correspon a la MAPK ERK5. La fosforilació d'aquesta proteïna podria estar directament relacionada amb la inhibició de la producció de IL-2 i per tant podria ser la via de senyalització mitjançant la qual sindecà-2 estaria exercint la seva acció inhibidora.
Syndecans bind cell adhesion molecules and growth factors and can act as correceptors, and in this way they can modulate leukocyte cell function. In the present thesis the expression of syndecans in primary human CD4 T cells has been analyzed. For this study monoclonal antibodies against syndecan-2 have been produced.
We show that, the stimulation of human CD4 T cells increases the amount of syndecan-4 remarkably, and in a lower extent that of syndecan-2. Expression of syndecan-2 and -4 show different induction kinetics. Whereas syndecan-4 expression is fast and significant, that of syndecan-2 is more delayed and short-lived decreasing its mRNA expression at day 4. Both CD45RA+ naïve and CD45RA- memory CD4 T cells express syndecan-2 and -4 upon activation.
When incubated with human peripheral blood lymphocytes in a mixed leukocyte reaction, anti-syndecan-4 but not anti-syndecan-2 antibodies, decreased T cell proliferation. However, cross-linking of cell-bound syndecan-2 or syndecan-4 via immobilized antibodies blocked proliferation and decreased TNF production of T cells in the presence of optimal levels of anti-CD3. These findings suggest that syndecan-2 and -4 acts as inhibitors of T cell activation.

We also investigated the role that MAPK signaling pathways play in control of syndecan expression in T cells. We show that production of syndecan-2 but not syndecan-4 requires signaling via p38 MAP kinase alpha/beta in T CD4 cells.

These studies provide evidence for the up-regulation of syndecan-2 and -4 in human primary CD4 T cells during in vitro activation and suggest an inhibitory role or these syndecans in CD4 T cells.

We also investigated the signaling pathways induced by syndecan-2 in T cells. We show that the triggering of syndecan-2 with antibodies promotes the phosphorylation of ERK5 MAP kinase. The phosphorylation of this protein could be directly related to inhibition of IL-2 production and therefore could be the signaling pathway that syndecan-2 uses to exert its inhibitory action.

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39

Lima, Jéssyca de Freitas. "Controle e remoção de sulfetos em reatores anaeróbios tratando esgoto sanitário." Universidade Estadual da Paraíba, 2015. http://tede.bc.uepb.edu.br/tede/jspui/handle/tede/2241.

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The process that occurs in anaerobic reactors called sulfetogênese is a process considered undesirable due to various problems he carries with the production of sulfides, causing: harsh odors, corrosion, toxicity and decreased concentrations of methane in the biogas. The present research aimed to develop processes to reduce the concentration of sulfides present in the effluent of anaerobic reactors in wastewater treatment. The experimental investigation was divided into two phases. In the first two Upflow Anaerobic reactors were used Sludge Blanket – UASB, one with low concentration of oxygen in the sludge blanket (UASB – O 2 ) and another with a UASB features without modification to be compared (UASB – control). In the second phase we used a Hybrid anaerobic reactor (RAH): composed of two overlapping UASB reactor ballasts at the bottom and an anaerobic filter at the top. When analyzing the results of the UASBs reactors, it was possible to identify that the addition of oxygen resulted in oxidation of the sulfide produced in the UASB reactor sulphate obtaining a final concentration in the effluent of 12.09± 3.22 mg S-SO 4 2 .L -1 -2 .L -1 and 2.54±1.92 mg S-S , inhibiting the stench and various problems related to the formation of sulfide on anaerobic reactors. The UASB – control, produced an effluent with a concentration of 13.20±8.65 mg S-S -2 .L -1 and 1.57±0.68 mg S-SO 4 -2 .L -1 by following the principles of an anaerobic reactor, when comparing with the other reactor. With the results obtained from the RAH was possible to assess that at the bottom (UASB) the sulfetogênese effectively occurred, reducing the sulfate contained in wastewater in sulphide and subsequently forming the hydrogen sulfide (H 2 S). At the top (filter) the oxidation of sulfide formed the elemental sulphur and sulphate, inhibiting so the stench of anaerobic reactors.
O processo que ocorre em reatores anaeróbios denominado de sulfetogênese é um processo considerado indesejável devido aos vários problemas que ele acarreta com a produção de sulfetos, causando: odores agressivos, corrosão, toxicidade e diminuição da concentração de metano no biogás. A presente pesquisa objetivou desenvolver processos para reduzir a concentração de sulfetos presente no efluente de reatores anaeróbios, no tratamento de águas residuárias. A investigação experimental foi dividida em duas fases. Na primeira foram utilizados dois reatores Upflow Anaerobic Sludge Blanket – UASB, um com baixa concentração de oxigênio na manta de lodo (UASB – O 2 ) e outro com características de um UASB sem modificações para serem comparados (UASB - Controle). Na segunda fase foi utilizado um Reator Anaeróbio Híbrido (RAH): composto por dois reatores sobrepostos, um reator UASB na parte inferior e um filtro anaeróbio na parte superior. Ao se analisar os resultados dos reatores UASBs, foi possível identificar que a adição de oxigênio resultou na oxidação do sulfeto produzido no reator UASB a sulfato obtendo uma concentração final no efluente de 12,09±3,22 mg S-SO 4 2- .L -1 e 2,54±1,92 mg S-S 2- .L -1 , inibindo o mau cheiro e diversos problemas relacionados com a formação de sulfeto em reatores anaeróbios. O UASB – Controle, produziu um efluente com uma concentração de 13,20±8,65 mg SS 2- .L -1 e 1,57±0,68 mg S-SO 4 2- .L -1 seguindo assim os princípios de um reator anaeróbio, ao comparar com o outro reator. Com os resultados obtidos do RAH foi possível avaliar que na parte inferior (UASB) a sulfetogênese ocorreu de forma efetiva, reduzindo o sulfato contido na água residuária a sulfeto e posteriormente formando o sulfeto de hidrogênio (H 2 S). Na parte superior (Filtro) ocorreu a oxidação do sulfeto formado à enxofre elementar e a sulfato, inibindo assim o mau cheiro de reatores anaeróbio.

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Barbosa, Rodrigo de Andrade. "Remoção de sulfetos e obtenção de enxofre elementar em reatores UASB com adição de oxidantes." Universidade Estadual da Paraíba, 2017. http://tede.bc.uepb.edu.br/jspui/handle/tede/2800.

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In the treatment of sanitary sewage in UASB reactors anaerobic digestion occurs, among the several processes that comprise it, sulfide produces sulfide, which causes several problems, such as: odor emanation, corrosion, toxicity and decrease of methane concentration in the Biogas. This research aims to improve processes to produce elemental sulfur and reduce the concentration of sulfides in the effluent and biogas of UASB reactors with the addition of oxidants in the treatment of sanitary sewage. The experimental investigation was divided into three phases. In the first one, three reactors were used, two microaerobes and a UASB reactor with addition of nitrate to the tributary. In the second phase, a microaerobic reactor and a UASB reactor with nitrate addition were operated. In the third phase two reactors were operated, one microaerobic and one UASB reactor (control). When analyzing the results of the reactor monitoring, it was possible to identify that the first-stage microaerobic reactors with sulfide removal efficiencies higher than 90%. And an elemental sulfur production of approximately 28% in relation to the total affluent sulfur. In the second phase the reactors also removed more than 90% of the total dissolved sulfide, but with respect to the elemental sulfur, the production had less expressive results. The nitrate addition reactors showed 98% of the sulphide removal 2- -1 efficiencies, with a mean concentration of 0.2 ± 0.06 mg S-S . L . In the third phase the microaeration provided a sulfide removal of 84% in the effluent and 97% in the biogas, with an average of 8 ppm. Then there was a reduction in the emanation of odors and several other problems related to high concentrations of sulphide in the effluent and in the biogas of UASB reactors.
No tratamento de esgoto sanitário em reatores UASB ocorre a digestão anaeróbia, dentre os vários processos que a compõem, a sulfetogênese ocasiona a produção de sulfetos, que acarreta vários problemas, como: emanação de odores, corrosão, toxicidade e diminuição da concentração de metano no biogás. Esta pesquisa tem como objetivo aprimorar processos para produzir enxofre elementar e reduzir a concentração de sulfetos no efluente e no biogás de reatores UASB com adição de oxidantes, no tratamento de esgoto sanitário. A investigação experimental foi dividida em três fases. Na primeira foram utilizados 3 reatores, dois microaeróbios e um reator UASB com adição de nitrato ao afluente. Na segunda fase foram operados um reator microaeróbio e um reator UASB com adição de nitrato. Na terceira fase foram operados dois reatores, um microaeróbio e um reator UASB (controle). Ao se analisar os resultados do monitoramento dos reatores, foi possível identificar que os reatores microaeróbios operados na primeira fase com eficiências de remoção de sulfeto superiores a 90%. E uma produção de enxofre elementar de aproximadamente 28% em relação ao enxofre total afluente. Na segunda fase os reatores também removeram mais de 90% do sulfeto total dissolvido, porém referente ao enxofre elementar, a produção teve resultados menos expressivos. Os reatores com adição de nitrato foram observados 98% de eficiências na remoção de 2- -1 sulfetos, com concentração média de 0,2 ± 0,06 mg S-S . L . Na Terceira fase a microaeração proporcionou uma remoção de sulfetos de 84% no efluente e de 97% no biogás, com média de 8 ppm. Então houve uma redução na emanação de odores e diversos outros problemas relacionados a concentrações elevadas de sulfeto no efluente e no biogás de reatores UASB.

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41

Kaschak, Elisabeth [Verfasser]. "Untersuchungen zur biotischen Bildung von Methylquecksilber aus anorganischem Quecksilber durch intestinale Sulfat-reduzierende Bakterien und die Bestimmung alkylierter Quecksilberverbindungen mittels GC-ICP-MS und Isotopenverdünnungsanalyse / Elisabeth Kaschak." Mainz : Universitätsbibliothek Mainz, 2013. http://d-nb.info/1035157489/34.

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42

Sim, Min Sub. "Physiology of multiple sulfur isotope fractionation during microbial sulfate reduction." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/77788.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 2012.
Cataloged from PDF version of thesis.
Includes bibliographical references.
Microbial sulfate reduction (MSR) utilizes sulfate as an electron acceptor and produces sulfide that is depleted in heavy isotopes of sulfur relative to starting sulfate. The fractionation of S-isotopes is commonly used to trace the biogeochemical cycling of sulfur in nature, but a mechanistic understanding of factors that control the range of isotope fractionation is still lacking. This thesis investigates links between the physiology of sulfate reducing bacteria in pure cultures and multiple sulfur isotope (³², ³³, ³⁴34S, and ³⁶S) fractionation during MSR in batch and continuous culture experiments. Experiments address the influence of nutrient and electron donor conditions, including organic carbon, nitrogen, and iron, in cultures of a newly isolated marine sulfate reducing bacterium (DMSS-1). An actively growing culture of DMSS-1 produced sulfide depleted in ³⁴S by 6 to 66%o, depending on the availability and chemistry of organic electron donors. The magnitude of isotope effect correlated well with the cell specific sulfate reduction rate (csSRR), and the largest isotope effects occurred when cultures grew slowly on glucose, a recalcitrant organic substrate. These findings bridge the long-standing discrepancy between the upper limit for S-isotope effect in laboratory cultures and the corresponding observations in nature and indicate that the large (>46 %o) fractionation of S-isotopes does not unambiguously record the oxidative sulfurrecycling. When the availability of iron was limited, the increase in S-isotope fractionation was accompanied by a decrease in the cytochrome c content as well as csSRR. In contrast, growth in nitrogenlimited cultures increased both csSRR and S-isotope fractionation. The influence of individual enzymes and electron carriers involved in sulfate respiration on the fractionation of S-isotopes was also investigated in cultures of mutant strains of Desulfovibrio vulgaris Hildenborough. The mutant lacking Type I tetraheme cytochrome c₃ fractionated ³⁴S/³²S ratio 50% greater relative to the wild type. The increasing S-isotope fractionation accompanied the evolution of H2 in the headspace and the decreasing csSRR. These results further demonstrate that the flow of electrons to terminal reductases imparts the primary control on the magnitude of the fractionation of S-isotopes, suggested by culture experiments using DMSS-1.
by Min Sub Sim.
Ph.D.

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43

Sánchez, Pastén Miguel [Verfasser]. "Korrosionsverhalten von Eisen, einem niedriglegierten Stahl, 9%Cr-Stählen, Nickel und einer Ni-Basislegierung unter einer simulierten Müllverbrennungsatmosphäre und Chlorid-Sulfat-Ablagerungen bei erhöhter Temperatur / Miguel Sánchez Pastén." Aachen : Shaker, 2006. http://d-nb.info/1166515877/34.

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44

Lovell, Jessica. "Long term organic carbon dynamics in 17 Swedish lakes : The impact of acid deposition and climate change." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-264516.

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During the last three decades, a number of studies based on national environmental monitoring data have found increased concentrations of total organic carbon (TOC) in surface waters in much of the northern hemisphere including Sweden. There are many hypothesis of what has been the main cause of this trend, including changes in land use, decreased atmospheric deposition of acidifying compounds and climate change. Different hypothesis may have different implications for quantifying pre-industrial levels and for future predictions of TOC concentrations, which in turn will have different implications for water classification according to the European Water Framework Directive, water management and drinking water treatment. To analyse the long term effects of industrialisation and climate change on TOC in surface waters there is a need for long term time series of data. Since environmental monitoring data in Sweden only extends back to the mid-1980s, other techniques must be used in order to reconstruct data. In this study, sediment cores from 17 lakes along a climatic and deposition gradient in Sweden were collected and analysed with visible near infrared spectroscopy (VNIRS), an analytical technique that makes it possible to reconstruct historic surface water concentrations of TOC to pre-industrial conditions. A previous study with VNIRS showed that TOC concentrations declined in response to sulfate deposition until peak sulfur deposition in 1980, and thereafter increased as a result of sharp reductions of sulfate emissions. It was noted that the rate of increase of TOC after 1980 was faster than the rate of decrease due to sulfate deposition before 1980. The purpose of this study was therefore to explore the hypothesis that increasing TOC concentrations have not only been due to recovery from acidification, but also due to changes in climate. It was possible to analyse the long term effects of industrialisation and climate change on surface water TOC by analysing the reconstructed TOC data together with climate data from the beginning of the 1900s, modelled data of atmospheric sulfate deposition and environmental monitoring data, with uni- and multivariate analysis methods. It was found that the recent increase in TOC concentrations could be explained by both decreases in acidifying atmospheric deposition and increased precipitation, while temperature may have a decreasing effect on TOC. It was also found that the rate of increase of TOC-concentrations has been faster in the colder northern parts of Sweden and slower in the warmer south. The results imply that TOC concentrations will continue to rise to unpreceded levels and should be of concern for drinking water treatment plants that will need to adapt their treatment processes in the future.
Under de senaste tre årtiondena har ett flertal studier baserade på data från nationella miljöövervakningsprogram rapporterat ökande koncentrationer av organiskt kol (TOC) i ytvatten på norra halvklotet inklusive Sverige. Det finns många hypoteser om vad som ligger bakom trenden, till exempel förändringar i markanvändning, minskad atmosfärisk deposition av försurande ämnen och klimatförändringar. Olika förklaringar till vad som ligger bakom den ökande trenden ger konsekvenser vid kvantifiering av förindustriella nivåer och för förutsägelser om framtida koncentrationer, vilket i sin tur ger konsekvenser för vattenklassificering enligt Ramvattendirektivet, vattenförvaltning och dricksvattenberedning. För att kunna analysera de långsiktiga effekterna av industrialisering och klimatförändringar på TOC i ytvatten behövs långa tidsserier av data. Då den svenska miljöövervakningen endast sträcker sig tillbaka till mitten av 1980-talet måste andra tekniker användas för att rekonstruera data. I den här studien har sedimentproppar från 17 sjöar längs en klimat- och depositionsgradient analyserats med visible near infrared spektroskopi (VNIRS), en analysteknik som gör det möjligt att rekonstruera TOC-koncentrationer i ytvatten till förindustriell tid. En tidigare studie med VNIRS visade att TOC-koncentrationer sjönk till följd av försurande nedfall fram till 1980 då nedfallet kraftigt minskade, varefter koncentrationer av TOC började öka. Det noterades i studien att ökningen av TOC efter 1980 varit snabbare än vad minskningen var före 1980 på grund av försurande nedfall. Syftet med den här studien var därför att undersöka hypotesen att den senaste tidens ökning av TOC inte bara berott på minskat nedfall av försurande ämnen, utan även på grund av klimatförändringar. Det var möjligt att undersöka de långsiktiga effekterna av industrialisering och klimatförändringar på TOC i ytvatten genom att analysera rekonstruerad TOC data, klimatdata från början av 1900-talet, modellerad sulfatdepositionsdata och miljöövervakningsdata med uni- och multivariata analysmetoder. Resultaten visade att den senaste tidens ökning av TOC kunde förklaras med både en minskande deposition av försurande ämnen och en ökad nederbörd, medan ökande temperaturer kan ha haft en minskande effekt på TOC. Resultaten visade även att förändringshastigheten av TOC-koncentrationer varit snabbare i de norra, kalla delarna av Sverige och långsammare i de varmare södra. Resultaten indikerar att koncentrationer av TOC kommer att öka till nivåer som aldrig tidigare skådats, vilket är något vattenreningsverk kommer att behöva anpassa sina reningsmetoder till i framtiden.

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Beck, Jan-Philipp [Verfasser], Birgitta-C. [Akademischer Betreuer] Burckhardt, and Oliver [Akademischer Betreuer] Groß. "Regulation des Sulfat-Anionen-Transporters-1, sat-1, in Caco2-Zellen durch Oxalat und dessen Vorstufen / Jan-Philipp Beck. Gutachter: Birgitta-C. Burckhardt ; Oliver Groß. Betreuer: Birgitta-C. Burckhardt." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2014. http://d-nb.info/1064148042/34.

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46

Posern, Konrad [Verfasser], Christian [Akademischer Betreuer] Kaps, Franziska [Gutachter] Scheffler, and Michael [Gutachter] Steiger. "Untersuchungen von Magnesiumsulfat-Hydraten und Sulfat/Chlorid-Mischungen für die Eignung als Aktivstoff in Kompositmaterialien für die thermochemische Wärmespeicherung / Konrad Posern ; Gutachter: Franziska Scheffler, Michael Steiger ; Betreuer: Christian Kaps." Weimar : Professur Bauchemie und Polymere Werkstoffe, 2012. http://d-nb.info/1115806882/34.

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47

Blázquez, Ribas Enric. "Promoting autotrophic sulfate reduction and elemental sulfur recovery in bioelectrochemical systems." Doctoral thesis, Universitat Autònoma de Barcelona, 2019. http://hdl.handle.net/10803/667334.

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Les activitats industrials com són les industries papereres, farmacèutiques, minera, de processat d’aliments, etc. generen aigües residuals amb un alt contingut de sulfat. El sulfat com a tal no resulta altament perjudicial per a la salut, però si s’aboca en rius o sistemes de clavegueram, els microorganismes coneguts com bactèries reductores de sulfat (sulfate reducing bacteria, SRB) el poden transformar en sulfur d’hidrogen. El sulfur d’hidrogen és un compost que fa mala olor, és corrosiu i s’ha demostrat tòxic inclús a baixes concentracions. Per aquests motius el tractament d’efluents rics en sulfat és indispensable. A més a més, la recuperació de sofre elemental d’aquests efluents per poder ser reutilitzat com a fertilitzant o matèria primera a la indústria és una oportunitat de recuperació de recursos en el marc de l’economia circular. Els sistemes bioelectroquímics (bioelectrochemical systems, BES) són una tecnologia innovadora basada en l’habilitat d’alguns bacteris d’intercanviar electrons amb un elèctrode sòlid. Últimament, l’estudi dels BES s’ha focalitzat en el tractament d’aigües residuals i en la recuperació de productes gràcies a l’activitat dels microorganismes que colonitzen els elèctrodes. En aquesta tesi s’ha estudiat l’ús de BES per al tractament i recuperació de compostos de sofre, concretament, el tractament d’aquestes aigües residuals amb sulfat. El sistema permet la reducció de sulfat en un biocàtode mentre en l’ànode succeeix l’electròlisi d’aigua per generar el flux d’electrons necessari. Els microorganismes que colonitzen la superfície del càtode utilitzen l’hidrogen generat a partir dels electrons per transformar el sulfat en sulfur d’hidrogen. No obstant això, els resultats obtinguts han demostrat que gràcies a l’electròlisi de l’aigua que té lloc a l’ànode es produeix un flux d’oxigen cap al càtode que permet el creixement dels microorganismes capaços de produir sofre a partir del sulfur d’hidrogen, anomenats bacteris oxidants de sulfur (sulfide oxidising bacteria, SOB). Per tal de millorar l’eliminació de sulfat i la producció de sofre es va estudiar com el pH del compartiment del càtode i el potencial de càtode podien influir en el procés. Es va observar que el pH neutre (pH = 7) era més beneficiós ja que un pH àcid (pH = 5.5) podria inhibir l’activitat de les SRB i un pH bàsic (pH = 8.5) requeria de més energia per aconseguir resultats similars a causa de la limitació en la producció d’hidrogen a un pH elevat. En quant al potencial del càtode, es va poder observar que a menors potencials, major eliminació de sulfat, però a partir d’un potencial de -1.0 V vs. SHE, el sistema no podia augmentar la velocitat d’eliminació. A més a més, també s’ha estudiat el tractament d’aigua residual real procedent d’un sistema de dessulfuració de gasos de combustió. S’ha observat que amb l’aigua real l’eliminació de sulfat es reduïa, però en canvi la producció de sofre elemental augmentava. Finalment, com que el flux d’oxigen de l’ànode al càtode no es podia controlar amb els sistemes anteriors, s’han dissenyat dues noves configuracions per poder millorar la producció de sofre elemental. La primera ha consistit en l’addició d’una cel·la electroquímica per tal d’oxidar el sulfur d’hidrogen en l’ànode permetent el control del potencial i així poder-ne controlar la producció. La segona configuració ha consistit en l’addició d’una cel·la de combustible amb un càtode exposat a l’aire aprofitant la capacitat del sulfur d’hidrogen a ser oxidat en un ànode espontàniament i així produir energia en comptes de requerir-la en el procés d’oxidació.
Las actividades industriales tales como las industrias papeleras, farmacéuticas, minera, de procesado de alimentos, etc. generan aguas residuales con un alto contenido en sulfato. El sulfato como tal no resulta muy perjudicial para la salud, pero si se vierte en ríos o sistemas de alcantarillado, los microorganismos conocidos como bacterias reductoras de sulfato (sulfate reducing bacteria, SRB) lo pueden transformar en sulfuro de hidrógeno. El sulfuro de hidrógeno es un compuesto que huele mal, es corrosivo y se ha demostrado tóxico incluso a bajas concentraciones. Por estos motivos, el tratamiento de efluentes ricos en sulfato es indispensable. Además, la recuperación de azufre elemental de estos efluentes para poder ser reutilizado como fertilizante o materia prima en la industria es una oportunidad de recuperación de recursos en el marco de la economía circular. Los sistemas bioelectroquímicos (bioelectrochemical systems, BES) son una tecnología innovadora basada en la habilidad de algunas bacterias de intercambiar electrones con un electrodo sólido. Últimamente, el estudio de los BES se ha focalizado en el tratamiento de aguas residuales y en la recuperación de productos gracias a la actividad de los microorganismos que colonizan los electrodos. En esta tesis se ha estudiado el uso de BES para el tratamiento y recuperación de compuestos de azufre, concretamente, el tratamiento de estas aguas residuales con sulfato. El sistema permite la reducción de sulfato en un biocátodo mientras en el ánodo se produce la electrólisis del agua para generar el flujo de electrones necesario. Los microorganismos que colonizan la superficie del cátodo utilizan el hidrógeno generado a partir de los electrones para transformar el sulfato en sulfuro de hidrógeno. Sin embargo, los resultados obtenidos han demostrado que gracias a la electrólisis del agua que tiene lugar en el ánodo se produce un flujo de oxígeno hacia el cátodo que permite el crecimiento de microorganismos capaces de producir azufre a partir del sulfuro de hidrógeno, llamados bacterias oxidantes de sulfuro (sulfide oxidizing baceria, SOB). Para mejorar la eliminación de sulfato y la producción de azufre se estudió como el pH del compartimento del cátodo y el potencial de cátodo podían influir en el proceso. Se observó que el pH neutro (pH = 7) era más beneficioso ya que un pH ácido (pH = 5.5) podría inhibir la actividad de las SRB y un pH básico (pH = 8.5) requería más energía para conseguir resultados similares debido a la limitación en la producción de hidrógeno a un pH elevado. En cuanto al potencial del cátodo, se pudo observar que a menores potenciales, mayor eliminación de sulfato, pero a partir de un potencial de -1.0 V vs. SHE, el sistema no podía aumentar la velocidad de eliminación. Además, también se ha estudiado el tratamiento de agua residual real procedente de un sistema de desulfuración de gases de combustión. Se ha observado que con el agua real la eliminación de sulfato se reducía, pero en cambio la producción de azufre elemental aumentaba. Finalmente, dado que el flujo de oxígeno del ánodo al cátodo no se podía controlar con los sistemas anteriores, se han diseñado dos configuraciones nuevas para mejorar la producción de azufre elemental. La primera ha consistido en la adición de una celda electroquímica para oxidar el sulfuro de hidrógeno en el ánodo permitiendo el control del potencial y así poder controlar la producción. La segunda configuración ha consistido en la adición de una celda de combustible con un cátodo expuesto al aire aprovechando la capacidad del sulfuro de hidrógeno a ser oxidado en un ánodo espontáneamente y así producir energía en vez de requerirla en el proceso de oxidación.
Industrial activities such as paper, pharmaceutical, mining, food processing, etc. generate wastewater with high sulfate content. Sulfate as such is not very harmful to health, but if it is poured into rivers or sewage systems, the microorganisms known as sulfate reducing bacteria (SRB) can transform it into hydrogen sulfide. Hydrogen sulfide is a compound with bad odour, is corrosive and has been shown toxic at low concentrations. For these reasons, the treatment of sulfate-rich effluents is essential. In addition, the recovery of elemental sulfur from these effluents in order to be reused as fertilizer or raw material in the industry is an opportunity to recover resources in the framework of the circular economy. Bioelectrochemical systems (BES) are a novel technology based on the ability of some bacteria to exchange electrons with a solid electrode. Lastly, the study of the BES has focused on the treatment of wastewater and the recovery of products thanks to the activity of the microorganisms that colonize the electrodes. In this thesis, the use of BES for the treatment and recovery of sulfur compounds was studied, specifically, the treatment of these wastewaters with sulfate in a biocathode. The system allows the reduction of sulfate at a biocatode while at the anode electrolysis of water occurs to generate the necessary electron flow. The microorganisms that colonize the surface of the cathode use the hydrogen produced from the electrons to transform the sulfate into hydrogen sulfide. However, the results obtained showed that thanks to the water electrolysis that takes place at the anode an oxygen flow to the cathode is generated, allowing the growth of microorganisms capable of producing sulfur from hydrogen sulfide, called sulfide oxidizing bacteria (SOB). The influence of pH of the cathode compartment and the cathode potential was studied in order to improve sulfate removal and sulfur production. It was observed that neutral pH (pH = 7) was more beneficial since an acidic pH (pH = 5.5) could inhibit the activity of the SRB and a basic pH (pH = 8.5) required more energy to achieve similar results due to the limitation in the production of hydrogen at a high pH. Regarding the potential of the cathode, it could be observed that lower potentials led to greater sulfate removal rate, but from a potential of -1.0 V vs. SHE, the system could not increase the removal rate. In addition, the impact of real wastewater coming from a flue gas desulphurization system in the system was also studied. It was observed that with real water the sulfate removal decreased, however, the production of elemental sulfur increased. Finally, since the oxygen flow from the anode to the cathode could not be controlled with the previous systems, two new configurations were designed to improve the production of elemental sulfur. The first one consisted in the addition of an electrochemical cell to oxidize the hydrogen sulfide at the anode, allowing the control of the potential and thus controlling the production. The second configuration consisted in the addition of a fuel cell with a cathode exposed to the air taking advantage of the capacity of the hydrogen sulfide to be oxidized at an anode spontaneously and thus produce energy instead of requiring it in the oxidation process.

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48

Leavitt, William Davie. "On the mechanisms of sulfur isotope fractionation during microbial sulfate reduction." Thesis, Harvard University, 2014. http://dissertations.umi.com/gsas.harvard:11511.

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Underlying all applications of sulfur isotope analyses is our understanding of isotope systematics. This dissertation tests some fundamental assumptions and assertions, drawn from equilibrium theory and a diverse body of empirical work on biochemical kinetics, as applied to the multiple sulfur isotope systematics of microbial sulfate reduction. I take a reductionist approach, both in the questions addressed and experimental approaches employed. This allows for a mechanistic, physically consistent interpretation of geological and biological sulfur isotope records. The goal of my work here is to allow interpreters a more biologically, chemically and physically parsimonious framework to decipher the signals coded in modern and ancient sulfur isotope records.
Earth and Planetary Sciences

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Gunnarsson, Niklas. "Mineralogical speciation of sulfur in acid sulfate soils from Luleå, Sweden." Thesis, Luleå tekniska universitet, Geovetenskap och miljöteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-71759.

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Marine sulfide – bearing sediments that oxidize when in contact with oxygen and leach outelements in high concentrations to small watercourses have been a problem for many years allover the world especially around the Bothnian Bay. The purpose of this study was to furtherinvestigate the sulfur mineralogy present in acid sulfate soils in the area of Luleå, Sweden. Asecondary aim was to see if elements leach out and accumulate in an acid sulfate soil closer tothe recipient. Samples were taken in two profiles (one oxidized and one waterlogged) fromfour sites (sites A-D) and were analyzed for whole rock geochemistry. Two sites were furtherinvestigated for mineralogy in polished samples with an optical microscope, Ramanspectroscopy and SEM-EDS. Each profile consisted of three layers: oxidation zone, transitionzone and reduced zone. The oxidation zone above the groundwater table was light grey withbrown iron hydroxide staining. Parts that lied under the water table were dark grey-black within general strong odor (“rotten eggs”) due to its sulfur content. It was usually straightforwardto distinguish and separate the layers from each other directly in the field, however in somecases pH was needed for confirmation.A general feature of investigated polished samples is the presence of abundant framboidalpyrites that are common in reduced marine sediments. The transition zone was formed in suboxicconditions and this feature is reflected by the mineralogy. Many morphologies of theframboidal pyrite were observed in this layer and signs of both dissolution and formationoccur. In the sample from site C one could observe elemental sulfur in form of large (up to 50μm) euhedral crystals. In the samples with pH<4, no sulfides occur as they have been replacedby jarosite (site B). Site C lacks these sulfur-bearing hydroxides which is thought to be due toa sulfur concentration of <0.2 %. Sulfur shows extensive leaching at most sites but at site B andD1, it accumulates in the transition zone. Elements like cobalt (Co), nickel (Ni) and zinc (Zn)are leached out or are accumulated further down in the profile. Elements that could have beentransported and have accumulated in the waterlogged profiles are Co, Ni, Zn and chromium(Cr) and in some profiles also copper (Cu) and vanadium (V).
Coastal watercourses in Bottenviken: Method development and ecological restoration- A cross-border Swedish-Finnish cooperation project

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Martinez, Mathieu. "Spéciation et isotopie du soufre inorganique en milieu aqueux." Thesis, Pau, 2019. http://www.theses.fr/2019PAUU3009/document.

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Le soufre existe dans l’hydrosphère dans des état d’oxydation allant des sulfates (+VI) aux sulfures (-II) et incluant de nombreuses espèces à des états d'oxydation intermédiaires, telles que le soufre élémentaire (0), les thiosulfates (-I, V) et les sulfites (IV). Ces espèces en particulier sont considérées comme des intermédiaires importants dans les réactions biologiques et abiotiques qui transforment (oxydent, réduisent ou dismutent) le soufre et sont fréquemment couplées aux cycles biogéochimiques du carbone, de l’azote, de l'oxygène et du fer.Les processus du cycle du soufre sont étudiés en mesurant les concentrations des différentes espèces contenant du soufre (analyse de spéciation) et en mesurant leur rapport isotopique respectif (analyse isotopique). Des difficultés analytiques sont fréquemment rencontrées, car les espèces soufrées, notamment celles de valence intermédiaire, sont présentes en faibles concentrations et sont difficiles à isoler. Ainsi, les rapports isotopiques des espèces de valence intermédiaire sont rarement déterminés. Les études des processus du cycle du soufre gagneraient grandement à l'amélioration des méthodes de mesure des rapports isotopiques des espèces de soufre inorganiques, en particulier des espèces intermédiaires les moins abondantes.Dans ce contexte, ce travail de thèse s’est consacré à l’élaboration de stratégies analytiques combinant spéciation et isotopie du soufre, afin de réaliser la mesure des rapports isotopiques du soufre de plusieurs espèces inorganiques présentes simultanément dans des échantillons liquides. Une méthode de spéciation permettant de quantifier les sulfites, les sulfates et les thiosulfates par chromatographie liquide couplée à un spectromètre de masse à plasma à couplage inductif haute résolution (LC-HR-ICP-MS) a tout d’abord été mise en place. Ensuite, une approche hors-ligne a été développée pour l’analyse isotopique des sulfures, des sulfates et des thiosulfates. Elle consiste en une préparation d’échantillon par précipitation séquentielle des espèces soufrées, suivie de leur analyse par analyseur élémentaire couplé à un spectromètre de masse à rapport isotopique (EA-IRMS). Cette méthode permet de déterminer les valeurs de δ34S des sulfures, des sulfates et des thiosulfates avec des incertitudes de mesure inférieures à 0,5 ‰ pour des échantillons d’eau contenant au moins 27 µg de soufre. Cette méthode a été appliquée à l’étude d’eaux de source et d’eaux d’un aquifère profond et au suivi du fractionnement isotopique du soufre dans une culture de bactéries sulfato-réductrices.Un couplage entre séparation anionique et détection par spectromètre de masse à plasma à couplage inductif multicollecteur (LC-MC-ICP-MS) a été mis au point pour la détermination en ligne des valeurs de δ34S des sulfites, des sulfates et des thiosulfates. Cette méthode nous a permis de déterminer δ34S des sulfites, des sulfates et des thiosulfates pour des échantillons d’eau contenant 1 µg de soufre par espèce avec des incertitudes de mesure inférieures à 0,6 ‰
Sulfur is present in the hydrosphere at oxidation states ranging from sulfate (+VI) to sulfide (-II) and including many species at intermediate oxidation states, such as elemental sulfur (0), thiosulfate (-I, V) and sulfite (IV). These species in particular are considered as important intermediates in biological and abiotic reactions (oxidation, reduction or disproportionation) involving sulfur and are frequently coupled to the biogeochemical cycles of carbon, nitrogen, oxygen and iron.Sulfur cycle processes are studied by measuring the concentrations of different species containing sulfur (speciation analysis) and by measuring their respective isotope ratios (isotopic analysis). Analytical difficulties are frequently encountered because sulfur species, especially intermediate valence species, are present in low concentrations and are difficult to isolate. Thus, the isotope ratios of intermediate valence species are rarely determined. Methods for measuring isotope ratios of inorganic sulfur species, particularly the least abundant intermediate species, would be a great assistance in deciphering sulfur cycle processes.In this context, this thesis work was devoted to the development of analytical strategies combining speciation and isotopic analysis of sulfur, in order to measure sulfur isotope ratios of several inorganic species that can be simultaneously present in liquid samples. First, a speciation method for quantifying sulfite, sulfate and thiosulfate by liquid chromatography coupled to high-resolution inductively coupled plasma mass spectrometer (LC-HR-ICP-MS) was set up. Then, an off-line approach was developed for the isotopic analysis of sulfide, sulfate and thiosulfate. It consisted of a sample preparation by sequential precipitation of the sulfur species, followed by elemental analyzer coupled to isotope ratio mass spectrometer (EA-IRMS) analysis. This method made it possible to determine the δ34S values of sulfide, sulfate and thiosulfate with measurement uncertainties below 0.5 ‰ for water samples containing at least 27 µg of sulfur. This method has been applied to the study of spring waters and deep aquifer waters and the monitoring of isotopic fractionation of sulfur in a culture of sulfate-reducing bacteria.Moreover, an on-line analytical method coupling anionic separation and detection by multicollector inductively coupled plasma mass spectrometer (LC-MC-ICP-MS) has been developed for the determination of δ34S values of sulfite, sulfate and thiosulfate. This method allowed us to determine δ34S of sulfite, sulfate and thiosulfate for water samples containing as little as 1 µg of sulfur per species with measurement uncertainties below 0.6 ‰

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Dissertations / Theses on the topic 'Sulfat'

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