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Mandarini, Elisabetta. "Decoding the role of HSPGs in tumor onset and progression through use of branched peptide probe." Doctoral thesis, Università di Siena, 2020. http://hdl.handle.net/11365/1094789.
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Heparan sulfate Proteoglycans (HSPGs) play a number of signaling and structural roles in tumor progression and metastasis spread. The biological function of HSPGs resides in their ability of interaction with many different types of ligands like growth factors, morphogens, chemokines and proteins of extracellular matrix (ECM). These bindings activate signaling pathways that modulate major transformations of cancer cells, leading to tumor growth, migration, invasion and metastasis. HSPGs are over-expressed on cancer cell membranes. The tetra-branched peptide NT4 binds with high selectivity to different human cancer cells and tissues. Its ability to discriminate between tumor and healthy tissues resides in the high-affinity binding to HSPGs and can be exploited by conjugating NT4 with different functional units, like chemotherapeutical drugs and tracers for cancer cell imaging and therapy. In this work, we test NT4 ability to interfere with processes mediated by HSPGs in tumor cell adhesion, migration and matrix invasiveness. Since HSPGs modulate also neo-angiogenesis, because of their expression by endothelial cells of microvessels that generate new vasculature, we focus also on NT4 role in endothelial cell proliferation, migration and tube formation, in the presence of Fibroblast Growth Factor-2 (FGF-2). Since the internalization and trafficking behaviour of HSPGs seems to reveal a clathrin and caveolin- independent, but dynamin-dependent endocytic pathway, we investigate
the pathway used by NT4 to enter cells. Last, but not least, we radiolabel NT4 with 18F in order to measure tumor uptake and whole-body biodistribution in a mouse model of breast cancer, using in vivo PET imaging. NT4-HSPG interactions and consequent modulation of signaling pathways can prove the importance of NT4 peptide as a specific tool to enlighten the role of HSPG in tumor onset and progression.
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Ahmed, Yassir Ahmed Mohmed Ali. "Heparan sulfate-protein interactions : evidence for sulfate group-dependent selectivity." Thesis, University of Liverpool, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.539728.
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Heparan sulfates (HS) are a family of structurally diverse, sulfated polysaccharides located at the cell surface and in the extracellular matrix. They are distributed widely in virtually all metazoan organisms. The structural diversity occurs via variability in the positions of sulfation along the HS chain and in (l L-iduronic acid and D› glucuronic acid substitutions. There is now strong evidence that these molecules perform diverse functions in vivo through their ability to regulate the activity of different proteins. A wide variety of proteins have been found to be ligands for liS, including growth factors, cytokines, receptors, adhesion and matrix molecules, enzymes, coagulation factors and a variety of bacterial and viral coat proteins. Hence, there is a very significant need to determine the molecular basis of HS activity and HS-protein interactions, addressing important issues such as the degree of molecular selectivity. In this study, two model protein systems were selected to test the hypothesis that selective saccharide sequence and sulfation patterns regulate protein binding and activity. In the first model, heparin and chemically modified heparin saccharides were screened for Slit and Robo binding and activity, as signalling by Slit requires two receptors, Robo transmembrane proteins and HS. How liS controls Slit-Robo signalling is unclear. Competition and direct enzyme linked immunoassay (ELISA) data showed that heparin derivatives enhance the affinity of Slit-Robo binary and ternary complexes. Analytical gel filtration chromatography demonstrated that Slit associates with a soluble Robo fragment and heparin derivatives to form a ternary complex. Furthermore, retinal growth cone collapse triggered by Slit requires cell surface HS or exogenously added heparin derivatives. The data indicate a complex relationship between HS binding and Slit-Robo proteins, which support selectivity in regulation of signalling responses, but do not suggest requirement for strictly defined sequence. In the second model, HS saccharides were prepared by heparinase treatment of porcine mucosal HS and purified by size-exclusion and SAX-IIPLC chromatography. Purified or semi-purified complex sulfated HS 6-mer and 8-mer sequences were prepared. This library was screened for binding to FGF-l and FGF-2 using a competition ELISA, and for corresponding bioactivity (regulation of FGF-l and FGF-2 signalling using a BaF3 cell assay with defined FGF receptors). This screen identified fractions that bound and activated these ligands, and ones that did not. Selected structures were subjected to activity analysis after further separation using ion-pairing reverse phase (IPRP-HPLC). Structures with similar or identical size and sulfation content, but distinct sulfation sequences, differed widely in their bioactivity, though binding data alone did not necessarily predict activity. The results provided information that supports the view that a significant degree of specificity for activation of FGF biological activity is encoded in the complex sulfation sequences observed in lIS chains. However, is not simply related to sulfation pattern. Over~ll: the results from these two model protein systems suggest that the degree of selectiVIty or specificity of HS structures for regulation of biological activity is complex, and varies according to the proteins involved. Nevertheless, they provide the basis for lIS to act as an important modulator of protein function in a wide variety of biological systems.
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Proud, Andrew D. "Development of a protecting group for sulfate esters." Thesis, University of Edinburgh, 1999. http://hdl.handle.net/1842/12804.
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This work describes the development of a protecting group for sulfate monoesters in carbohydrates. After initial trial studies, the trifluoroethyl ester was selected as a suitable protecting group. The ester was formed from the sulfate by treatment with trifluoro diazoethane. This protection method is shown to be compatible with other common protecting groups used in carbohydrate chemistry. The protecting group is proven to be stable to the manipulations of many other protecting groups. The utility of monosaccharides incorporating protected sulfate esters in synthesis has been examined. It has been proven that they are useful and versatile building blocks in the synthesis of more complex structures. Selective cleavage of the trifluoroethyl ester was achieved with potassium tert-butoxide. The mechanism for this deprotection reaction has been studied and this investigation has led to the advancement of alternative deprotection methods.
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Arai, Milton Hideaki. "Papel da atividade física regular realizada durante vários anos na função imune do idoso." Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/5/5144/tde-14102014-093413/.
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A proposta principal deste estudo foi de avaliar o efeito da prática regular de atividade física por longos anos na imunossenescência, isto é, nas alterações que o sistema imune sofre com o envelhecimento. Para tal, comparou-se os resultados dos exames imunológicos de 20 idosos praticantes de corrida (idade média = 67 anos) aos de 20 idosos sedentários (idade média = 66 anos) e 10 jovens sedentários (idade média = 26 anos). Os idosos corredores eram praticantes da modalidade em média nos últimos 23 anos e vinham percorrendo uma distância semanal média de 39 quilômetros. O consumo máximo de oxigênio (VO2 max) deles foi 52% maior do que o dos idosos sedentários, atingindo valores similares aos dos jovens. Os parâmetros imunológicos analisados foram: contagem de linfócitos e seus subtipos, resposta proliferativa dos linfócitos T a mitógenos, atividade citotóxica das células natural killer e produção de citocinas (interleucinas 2, 3, 4, 6, 10 e 12). A dosagem das mesmas citocinas no soro também foi realizada, porém somente nos dois grupos de idosos. Os idosos corredores apresentaram resposta proliferativa dos linfócitos T a OKT-3 e produção de interleucina-2 significativamente maiores do que as dos idosos sedentários. Eles apresentaram também uma produção de interleucina-3 significativamente menor do que a dos seus pares sedentários. Por outro lado, não apresentaram diferença significativa destes parâmetros em relação aos jovens. Os níveis séricos das interleucinas 3, 6 e 12 dos idosos corredores foram significativamente menores do que os dos idosos sedentários. A influência da prática de atividade física regular sobre os níveis séricos do hormônio de crescimento, da testosterona e da dehidroepiandrosterona sulfato (DHEAS), que sofrem redução com o envelhecimento (\"endocrinossenescência\"), também foi estudada. Não houve diferença significativa entre os níveis séricos destes hormônios anabólicos dos idosos corredores e dos idosos sedentários. O efeito da atividade física regular sobre a beta-endorfina também foi avaliado. Os idosos corredores não apresentaram diferença significativa nos níveis séricos deste neuropeptídeo em relação aos idosos sedentários. Em virtude do possível envolvimento do sistema endócrino na imunossenescência, avaliou-se a correlação entre os hormônios anabólicos e as citocinas. Não se constatou correlação relevante entre eles, especialmente entre a DHEAS e a interleucina-6. Os resultados indicam que a prática regular de atividade física por longos anos tem o potencial de desacelerar a imunossenescênciaThe main objective of this study was to assess the effect of regular practice of physical activity on immunosenescence, that is, the changes that occur when the immune system is affected by aging. The results of immune tests conducted on 20 elderly runners (mean age = 67 years) were compared to those of 20 elderly sedentary individuals (mean age = 66 years) and to those of 10 young sedentary individuals (mean age = 26 years). On average, the elderly runners had practiced this activity for the last 23 years, running a mean weekly distance of 39 kilometers. Their maximum oxygen consumption (VO2 max) was 52% higher than that of sedentary elderly group, and similar to that of the group of younger individuals. The immune parameters studied were: lymphocyte and lymphocyte subtype counts, the proliferative response of T-lymphocytes to mitogens, cytotoxic activity of natural killer cells and production of cytokines (interleukins 2, 3, 4, 6, 10 and 12). The same cytokines were measured in serum, but only in the two groups of elderly people. Elderly runners presented a significantly higher proliferative response of T-lymphocytes to OKT-3 as well as interleukin-2 production than the sedentary group. The production of interleukin-3 was also significantly lower in the group of runners. On the other hand, the results of these parameters did not differ significantly from those of young subjects. Serum levels of interleukins 3, 6, and 12 were significantly lower in elderly runners than in sedentary individuals. The impact of regular physical activity on serum levels of growth hormone, testosterone, and dehydroepiandrosterone sulfate (DHEAS), which are affected by aging (\"endocrinosenescence\"), was also studied. The serum levels of these anabolic hormones did not differ significantly between the groups of elderly runners and the elderly sedentary individuals. When the impact of regular physical activity on beta-endorphin was studied, again no significant difference in the serum levels of this neuropeptide was found between the two elderly groups. Owing to the possible involvement of the endocrine system in immunosenescence, the correlation between anabolic hormones and cytokines was assessed. No relevant correlation was found, especially between DHEAS and interleukin-6. The results indicate that the regular practice of physical activity for several years may delay immunosenescence
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Kotler, Julia Michelle. "Biosignature storage in sulfate minerals- synthetic and natural investigations of the jarosite group minerals." The University of Montana, 2009. http://etd.lib.umt.edu/theses/available/etd-08062009-143516/.
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The discovery of jarosite on Mars in 2004 generated increased interest in the properties of the mineral related to the search for life on other planets. Several studies indicate that the formation of jarosite can be linked to biological activity on Earth and biomolecules such as amino acids have been found associated with terrestrial jarosite samples. A series of natural and synthetic investigations using different jarosite end-members has been conducted and is presented in this dissertation to investigate the possibility that jarosite can store biosignatures. Natural samples were analyzed by x-ray diffraction, elemental carbon analysis and laser-desorption Fourier transform mass spectrometry (LD-FTMS) and were found to contain the amino acid glycine. Synthetic experiments were conducted in which the different end-members were synthesized in the presence of glycine as well as the amino acid alanine and the amino acid breakdown product methylamine. These samples were analyzed by x-ray diffraction, neutron diffraction, LD-FTMS and thermogravimetric analysis (TGA) techniques. Results of these experiments show that the detection of the biosignature and the effect that biomolecule has on the jarosite minerals is dependent on the end-member and indicate that the jarosite minerals are an excellent target for detecting potential signs of past life on other planets.
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Katragkou, Eleni. "Aircraft based measurements of atmospheric sulfur dioxide and ground based measurements of gaseous sulfur (VI) in the simulated internal flow of an aircraft engine implications for atmospheric aerosol formation /." [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=969654588.
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Matthews, Richard P. "Ion Pairing in Aqueous Metal Sulfates and Platinum Group Metal Ammonium Solutions." Doctoral thesis, University of Cape Town, 2010. http://hdl.handle.net/11427/6330.
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The structure and dynamics of ions and ion pairs in solution play an integral part in several biological and chemical processes. Historically the calculation of ion pair association constants from computer simulations has been complicated due to the difficulty in validating metal ion force fields for solution simulations. In this thesis a force field for divalent metal ions in metal sulfate solutions (i.e. Mg2+SO4 2-, Ca2+SO4 2-, Mn2+SO4 2-, Fe2+SO4 2-, Co2+SO4 2-, Ni2+SO4 2-, Cu2+SO4 2- and Zn2+SO4 2-) important in physical and biophysical experiments is produced. Potential of mean force calculations are used to provide ion pair free energy profiles and free energy perturbation calculations are used to calibrate the potential of mean force (PMF) from which association constants for ion pairs can be produced for these metal sulfate solutions. The calibrated free energy profiles result in calculated association constants that are in excellent agreement with available experimental data where available. Consequently the force field has been shown to be accurate for simulations of biophysical and physical systems. Furthermore the method, proposed in this thesis, for calibrating PMFs and calculating detailed association constants from those curves can most likely be used for complex systems that have previously been computationally inaccessible. Next a detailed account of solvation structures and the nature of ion pair formation mechanisms for important metal sulfates in aqueous media are presented. Radial and spatial distribution functions calculated for several ion pair species reveal that the transition from free ions to contact ion pairs involves the loss of between one to two water molecules from the cation depending on the cation size. This is correlated with the experimental hydration numbers calculated for metal sulfate electrolyte solutions at several concentrations using density and ultrasonic velocity measurements. These experiments reveal a decrease in hydration number with an increase in concentration, which can be attributed to the formation of ion pairs. A more complex metal system is the industrially important platinum group metal (PGM) chloro-anion one. Their industrial importance relates to the search for a Green Chemistry Process for the separation of PGM chloro complexes that have been extracted from the mined ore into an acidic aqueous media. This requires a PGM separation process in water. Here an understanding of the hydration structure about the iii PGM chloro-anion complexes and the role that ammonium counter-ions play in disrupting that solvent structure when ammonium PGM salts are formed, is critical in the process design. To this end a solution force field, inclusive of the majority of PGM chloro-anion complexes (i.e. (Y)2[PtCl4]2-, (Y)2[PdCl4]2-, (Y)2[PtCl6]2-, (Y)2[PdCl6]2-, (Y)2[IrCl6]2-, (Y)2[OsCl6]2-, (Y)2[RuCl6]2-, (Y)3[IrCl6]3-, (Y)3[RhCl6]3- and (Y)3[RuCl6]3- , where Y = NH4 +) arising in acidic aqueous media, parameterised from experimental and quantum mechanically derived properties, was developed. Nanosecond atomistic molecular dynamics simulations were then performed for the PGM chloro-anion complexes. Analysis of the solvation structure using radial and spatial distribution functions revealed two distinct solvent structures corresponding to the square planar and octahedral species. The formation of ion pairs disrupts the solvent structure where the hydration shells about the bivalent hexachlorometallates are more affected compared with the trivalent hexachlorometallates and these first shell waters in turn are more affected than those in the bivalent tetrachlorometallates. Finally to inform the design of a separation process transport properties such as diffusion coefficients, ion hydration numbers and water residence times for the PGM chloro-anion complexes were calculated. It is observed that the diffusion rates of PGM chloro-anion complexes are strongly correlated to their ion hydration numbers as calculated by Voronoi tessellation of the simulation cell, such that a larger hydration shell volume results in a slower PGM chloro-anion diffusion rate.
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Wuerch, Helmuth Victor. "Diagenesis and Water Chemistry of the Woodbine Group in the East Texas Basin." DigitalCommons@USU, 1986. https://digitalcommons.usu.edu/etd/6685.
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Petrographic and SEM study of flu vial-deltaic sections of the Woodbine Group in the East Texas Basin indicates that authigenic mineral suites are controlled, in part, by the presence of organic-rich matrix.
During early, precompaction diagenesis, organic matter supplied the metabolic fuel required by sulfate-reducing bacteria to reduce sulfate in depositional waters ultimately to pyrite. With burial the sulfate supply was ultimately exhausted, and bicarbonate activity thereafter controlled the precipitation of siderite and Fe-calcite.
Matrix material supplied the components and reaction sites for the most import ant porosity-occluding reaction: kaolinite --> Fe,M g chlorite. Matrix physically inhibited the growth of quartz overgrowths, yet, through compaction and as a product of the above reaction, provided a supply of silica for quartz cementation. Dissolution of salt dome cap rock has played a minor role in the cementation of the Woodbine in the East Texas Basin. Pore-filling calcite, barite, and pyrite were observed in the Woodbine where the Woodbine is in direct hydraulic communication with salt dome cap rock.
In the deep, central portion of the basin Na-Cl brine resulting from salt-dome dissolution is evolving toward a Na-Ca(Mg)-Cl brine. The evolution of the brine chemistry may be the result of cation exchange on clay minerals, albitization of plagioclase feldspars, or the dissolution of magnesium - and calcium- chloride-rich phases. The present study could not confirm any of these reactions.
WATEQF was used to calculate mineral-saturation states in Woodbine waters. Program output appears to represent accurately in situ individual mineral-saturation states at measured pH, as confirmed by petrographic and SEM identification of authigenic minerals. Relative stability between mineral pairs can be tested with thermodynamically-derived activity diagrams for the mineral pairs.
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Abdellatif, Mohamed Moustafa. "Poly(arylene ether)s with Truly Pendant Benzene Sulfonic Acid Groups." Wright State University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=wright1222544981.
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Mulwanda, James. "Recovery of dissolved platinum group metals from a pregnant copper sulphate leach solution by precipitation." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/86538.
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Thesis (MEng)--Stellenbosch University, 2014.ENGLISH ABSTRACT: In Base Metal Refineries (BMRs), the copper sulphate leach solution produced during the final pressure leaching stage contains impurities such as selenium and tellurium, as well as other precious metals (OPMs, namely Rh, Ru, and Ir). Se and Te are removed by precipitation with sulphur dioxide prior to electrowinning of Cu. While a small percentage of the dissolved OPMs precipitate with the Se and Te, the largest portion remains in solution and is recycled to the first stage leach. If a larger portion of the OPMs in solution can be recovered in the Se/Te precipitation stage, OPM losses and the OPM inventory of the plant can be reduced. The aim of this project was to determine operating conditions that would allow maximum OPM recovery with minimal Cu and Ni co-precipitation in the Se/Te removal section of a BMR. The effects that the operating temperature, pressure, stirring rate, reagent type, and reagent quantity have on the metal precipitation behavior and precipitate characteristics were determined experimentally. Thio-urea and sulphurous acid were evaluated as precipitation reagents for temperatures of 80°C and 160°C, stirring rates of 250 rpm and 500 rpm, and pressures equal to ambient pressure and 7 bar. 200 % and 320 % excess thio-urea and 720 % and 960 % excess sulphur dioxide were used. The precipitation of OPMs with sulphur dioxide was generally poor; the maximum percentage Rh, Ru, and Ir precipitated were 35 %, 18 %, and 20 %, respectively. It was, however, found that the OPM precipitation increased as the reagent amount was increased. Increasing the temperature further increased Rh and Ir precipitation but affected the Ru precipitation negatively. Thio-urea precipitated virtually all of the Rh contained in the solution irrespective of the values of the process variables studied. As was the case with sulphur dioxide, increasing the amount of thio-urea added resulted in increased Ru and Ir precipitation, while higher temperatures favored Ir precipitation but not Ru precipitation. The maximum percentage Ru and Ir precipitation achieved with thio-urea were 87 % and 60 %, respectively. Complete Se precipitation was observed at all process conditions, while Te precipitation increased as the operating temperature and the reagent quantity were increased. Maximum Te precipitation of 98 % and 90 % were achieved when using 320 % excess thio-urea and 960 % sulphurous acid quantities, respectively, at 160°C and a stirring rate of 250 rpm. Increasing the reagent quantity and temperature did, however, also result in increased copper and nickel precipitation. The statistical analysis of the results allowed regression models to be fitted to predict the percentage metal precipitation as a function of the investigated process variables. These models were used to define an objective function to determine the optimal operating conditions. A temperature of 80oC, a pressure of 7 bar, and 200 % excess thio-urea were proposed as the optimum operating conditions that would yield 98 % Rh, 75 % Ru, and 48 % Ir precipitation with less than 5 % Cu and Ni co-precipitation. Experimental validation tests confirmed the model predicted values and proved repeatability of the experimental data.
AFRIKAANSE OPSOMMING: Die kopersulfaat logingsoplossing wat tydens die finale drukloging stadium in Basis Metaal Raffinaderye (BMRe) produseer word, bevat onsuiwerhede soos selenium en tellurium sowel as ander edelmetale (AEMe, naamlik Rh, Ru, en Ir). Se en Te word voor Cu elektrowinning verwyder deur middel van presipitasie met swaweldioksied. Alhoewel ʼn klein persentasie van die opgeloste AEMe saam met die Se en Te presipiteer, bly die grootste gedeelte in oplossing en word gevolglik na die eerste loging stadium hersirkuleer. AEM verliese en die AEM inventaris van die aanleg kan verminder word indien ʼn groter gedeelte van die AEMe in die Se/Te presipitasie stadium herwin kan word. Die doel van hierdie projek was om bedryfstoestande te bepaal om maksimum AEM herwinning met minimale Cu en Ni kopresipitasie in die Se/Te verwyderingseksie van ʼn BMR te behaal. Die effekte wat bedryfstoestande soos temperatuur, druk, roerder tempo, tipe reagens, en hoeveelheid reagens op die metaal presipitasiegedrag en presipitaat eienskappe het, is eksperimenteel bepaal. Tio-ureum en swaweligsuur is evalueer as presipitasie reagense vir temperature van 80°C en 160°C, roerder tempo’s van 250 rpm en 500 rpm, en drukke gelyk aan omgewingsdruk en 7 bar. 200 % en 320 % oormaat tio-ureum en 720 % en 960 % oormaat swaweldioksied is gebruik. Die presipitasie van AEMe met swaweldioksied was swak in die algemeen; die maksimum persentasie Rh, Ru, en Ir presipitasie wat behaal is, is 35 %, 18 %, en 20 %, onderskeidelik. Daar is egter gevind dat die AEM presipitasie toeneem indien die hoeveelheid reagens toeneem. ʼn Toename in die temperatuur het verder tot ʼn toename in Rh en Ir presipitasie gelei, maar dit het Ru presipitasie negatief affekteer. Tio-ureum het basies al die Rh in oplossing laat presipiteer, ongeag die waardes van die ander prosesveranderlikes wat ondersoek is. Soos wat die geval vir swaweldioksied was, het ʼn toename in die hoeveelheid tio-ureum ʼn toename in die Ru en Ir presipitasie tot gevolg gehad, terwyl hoër temperature Ir presipitasie bevoordeel en Ru presipitasie benadeel het. Die maksimum persentasie Ru en Ir presipitasie wat met tio-ureum behaal is, is 87 % en 60 %, onderskeidelik. Volledige Se presipitasie is by alle proses toestande waargeneem, terwyl Te presipitasie toegeneem het soos wat die temperatuur en die hoeveelheid reagens toegeneem het. Maksimum Te presipitasie van 98 % en 90 % is behaal toe 320 % oormaat tio-ureum en 960 % oormaat swaweligsuur, onderskeidelik, by 160°C en ʼn roerder tempo van 250 rpm gebruik is. ʼn Toename in die hoeveelheid reagens en die temperatuur het egter ook meer koper en nikkel presipitasie tot gevolg gehad. Die statistiese analise van die resultate het dit moontlik gemaak om regressie modelle te pas om die persentasie metaal presipitasie as ʼn funksie van die ondersoekte veranderlikes te voorspel. Hierdie modelle is gebruik om ʼn doelfunksie te definieer ten einde die optimale bedryfstoestande te bepaal. ʼn Temperatuur van 80°C, ʼn druk van 7 bar, en 200 % oormaat tioureum is voorgestel as die optimale bedryfstoestande wat 98 % Rh, 75 % Ru, en 48 % Ir presipitasie met minder as 5 % Cu en Ni kopresipitasie tot gevolg sal hê. Eksperimentele geldigheidsbepalingtoetse het die waardes wat deur die modelle voorspel is bevestig en die herhaalbaarheid van die eksperimentele data bewys.
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Schumacher, Trevor I. "Poly(arylene ether sulfone)s with Ammonium Groups Located on PendentPhenyl Sulfonyl Moieties for Anionic Exchange Membranes." Wright State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=wright1468932871.
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Mujumdar, Prashant. "Synthesis and Biological Evaluation of Unusual Natural Products and Novel Heterocyclic Chemotypes as Carbonic Anhydrase Inhibitors." Thesis, Griffith University, 2017. http://hdl.handle.net/10072/366972.
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Carbonic anhydrases (CAs) are zinc metalloenzymes that catalyze the reversible hydration of carbon dioxide to bicarbonate and a proton. The zinc cation in the active site of these metalloenzymes is the suggested target for small molecule inhibitors to block the endogenous CA catalysed reaction. Almost all reported CA inhibitors consist of zinc binding group (ZBG) among which the, primary sulfonamide group (-SO2NH2) is the most prominent example. Primary sulfamate (-OSO2NH2) and primary sulfamide (-NH-SO2NH2) groups also serve as zinc binding groups in CA inhibitors, however they are less represented than the primary sulfonamide group. Natural products (NPs) have proven an invaluable source of compounds for drug discovery. NPs containing primary sulfonamide (-SO2NH2) and primary sulfamate (-OSO2NH2) group are rare, while there are no NP primary sulfamides. A literature search of the Dictionary of Natural Products (DNP) database revealed only two primary sulfonamide and five primary sulfamate compounds. This project will focus on the tractable synthesis of these rare natural products, biological evaluation against CA and protein X-ray crystal structures in complex with medicinally important isozymes of CA.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Natural Sciences
Science, Environment, Engineering and Technology
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Miller, Suzanne M. "Examination of specific amino acid residues of desulfovibrio desulfuricans cytochrome C₃ in electron transfer." Diss., Columbia, Mo. : University of Missouri-Columbia, 2005. http://hdl.handle.net/10355/4252.
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Thesis (M.S.)--University of Missouri-Columbia, 2005."December 2005" The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Vita. Includes bibliographical references.
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Kern, Kimberly E. "Poly(arylene ether sulfone)s Carrying Pendant(3-sulfonated) phenyl sulfonyl Groups for use as Proton Exchange Membranes." Wright State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=wright1308770965.
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PETIT, EMMANUEL. "Synthese et etudes physico-chimiques de glucuronane et glucoglucuronane substitues par des groupes sulfate et hydrophobe en vue d'applications dans la regeneration tissulaire." Amiens, 2000. http://www.theses.fr/2000AMIE0103.
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Des polysaccharides specifiques, d'origine naturelle ou non, interagissent avec les facteurs de croissance afin d'activer le deroulement des processus de la cicatrisation et de la reparation des tissus leses. En raison de leurs effets sur la reparation tissulaire ces polymeres ont ete denommes rgtas pour regenerating agent. L'activite biologique des rgtas semble liee a la presence sur une meme chaine de groupes fonctionnels carboxylates et sulfates, l'introduction de groupes hydrophobes pouvant moduler leur activite. L'objectif de notre travail a consiste a partir de deux polysaccharides microbiens originaux : le glucuronane et le glucoglucuronane, a synthetiser des rgtas qui ont ete testes in vivo. Deux types de modifications ont ete apportes sur les polymeres : $$ la balance hydrophile / hydrophobe des polysaccharides a ete modifiee par l'introduction d'une chaine alkyle en c12. Les derives obtenus, en depit d'une forte degradation de la chaine macromoleculaire, presentent des proprietes rheologiques interessantes. $$ l'introduction de groupes sulfate, a ete realisee grace a d'un complexe so 3 / dimethylformamide. L'ensemble des derives synthetises se sont reveles actifs avec des efficacites variables.
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Bartelmehs, Kurt Lane. "Bond length and bonded radii variations in sulfide molecules and crystals containing main group elements." Thesis, Virginia Polytechnic Institute and State University, 1987. http://hdl.handle.net/10919/91160.
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Molecular orbital calculations on 18 hydrosulfide molecules containing selected main group X-cations yield minimum energy bond lengths, Rt(XS), that reproduce those observed in chemically similar sulfide crystals. A least-squares analysis shows that Rt(XS) can be estimated by the equation R = l.83(s/r)-0.21, where s is the Pauling bond strength and r is the row number of the X-cation in the periodic table, with 98% of the variation of Rt(XS) being explained in terms of a linear dependence on R. In addition, R serves to rank observed XS bond lengths in sulfide crystals for main group X-cations for rows 1 through 5 of the periodic table to within 0.12Å on average, with R accounting for 96% of the variation in the observed bond lengths.
Bonded radii obtained from electron density maps calculated for the molecules show that the radii of both the X-cations and S atom increase with Rt(XS). A similar trend has been found to hold for the bonded radii and the Rt(XO) bond lengths calculated for hydroxyacid molecules (Finger and Gibbs 1985). The radius of S is smaller (1.16Å) when bonded to highly electronegative atoms like 4-coordinate As and larger (1.67Å) when bonded to a considerably less electronegative atoms like 4-coordinate Li but is smaller than Shannon's (1.70Å) crystal radius and Pauling's ionic crystal radius (1.84Å).M.S.
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Hanauer, Kristina [Verfasser]. "Ferrocene as redox-functional group in N,N'-disubstituted (thio)ureas and sulfite oxidase mimicking molybdenum complexes / Kristina Hanauer." Mainz : Universitätsbibliothek Mainz, 2018. http://d-nb.info/1164255835/34.
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Baltas, Michel. "Sulfinamides fonctionnalises inhibiteurs de la coniferylalcool deshydrogenase : synthese, etude de complexation par l'ion zn**(2+), mecanisme d'hydrolyse basique et aminolyse des sulfinamoyl acetates : schema d'inactivation enzymatique via un intermediaire sulfine." Toulouse 3, 1987. http://www.theses.fr/1987TOU30145.
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Kaukonen, R. (Risto). "Sulfide-poor platinum-group element deposits:a mineralogical approach with case studies and examples from the literature." Doctoral thesis, University of Oulu, 2008. http://urn.fi/urn:isbn:9789514289545.
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Abstract
Sulfide-poor deposits of platinum-group elements (PGE) occur in two main types: silicate-type and oxide-type. In the silicate-type mineralization PGE form discrete platinum-group minerals (PGM) that occur as inclusions in various silicate minerals. In the oxide-type mineralization PGM may have different modes of occurrence. They may be associated with silicates or they may occur as inclusions in chromite, magnetite or ilmenite, for example. In some cases they may even be associated with base metal sulfides.
The approach chosen in this work is mainly a mineralogical one. PGM parageneses, their modes of occurrence and associations with other minerals were studied from different deposits. These are then compared to some well-recorded examples of PGE deposits.
The case studies presented, the Duluth Complex in Minnesota, U.S.A., the Hanumalapur Complex in Karnataka, India, and the Penikat Layered Intrusion in northern Finland, are examples that illustrate the multitude of possibilities regarding PGE mineralization versus the traditional approach where any significant quantities of PGE are supposed to occur only in association with base metal sulfides.
As the traditional orthomagmatic and hydrothermal models cannot explain the genesis of some sulfide-poor PGE occurrences, a new theory of PGE mineralization was developed. This “redox theory” is an attempt at explaining the association of PGE with various oxide minerals, most importantly chromite.
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Le, Thi Kim-Thoa. "Luminescence de l'europium divalent dans les sulfures de magnésium ou d'éléments alcalino-terreux (sulfures MS, thioaluminates et thiosilicates)." Phd thesis, Université Sciences et Technologies - Bordeaux I, 1989. http://tel.archives-ouvertes.fr/tel-00168927.
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Dans la perspective de la réalisation de luminophores pour écrans cathodiques, une étude de la luminescence de l'europium dans des réseaux-hôtes soufres caracterisés par une large bande interdite a été réalisée. La première partie porte sur l'élaboration des sulfures MS et la détermination des facteurs influençant leurs rendements de photoluminescence et de cathodoluminescence. La seconde est consacrée a l'étude des systèmes MS-Al2S3 et MS-SiS2. De nouveaux thioaluminates ont ete isoles; les donnees cristallographiques sur les thiosilicates ont été complétées. La dernière partie rassemble les résultats d' une étude comparative de la luminescence de Eu2+ dans les thioaluminates, thiogallates et thiosilicates alcalino-terreux: distribution spectrale, rendements, extinction thermique...
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Permeh, Samanbar. "On the Role of the Pore Water Chemistry of Deficient Post-Tension Grout to Promote Steel Corrosion." FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/2445.
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Corrosion failure of post-tension tendons with pre-packaged thixotropic grout was documented in Florida Bridges in less than 10 years of service. Analysis of deficient grout in Florida post-tensioned (PT) bridges where severe corrosion developed indicated enhanced sulfate ion concentration, high pore water pH, enhanced moisture and low chloride content. The corrosion wasn’t consistent with the conventional causes of steel corrosion such as bleed water accumulation in grout void spaces, chloride contamination and pore water carbonation. Corrosion development was associated with deficient grout with enhanced sulfate levels. However, limited information is available on the corrosion behavior of PT strand in grout materials with enhanced sulfate content. Review of the technical literature has not shown consistent evidence of the role of sulfate ions in the corrosion of steel in solution and in hydrated cementitious material. In this research, the role of sulfates in cementitous materials was examined including identifying practical limits for sulfates in grout materials.
Laboratory samples were created with 15% and 20% excess water to enhance deficient grout materials and included enhanced sodium and chloride content. Enhanced sulfate and chloride ion presence was thought to provide aggressive corrosion condition of steel in segregated grout. Testing was intended to differentiate the corrosion of steel in pore water condition of deficient grout.
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Pessayre, Stéphanie. "Action concertée entre un métal noble et une phase sulfure pour l'hydrotraitement poussé des gazoles." Lyon 1, 2000. http://www.theses.fr/2000LYO10178.
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Demirci, Umit Bilge. "Caractère bifonctionnel particulier des catalyseurs Pt, Ir, ou Pd supportés sur zircone sulfatée dans les réactions de reformage d'alcanes." Université Louis Pasteur (Strasbourg) (1971-2008), 2002. https://publication-theses.unistra.fr/public/theses_doctorat/2002/DEMIRCI_Umit_Bilge_2002.pdf.
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Le travail décrit dans ce mémoire concerne l'isomérisation des n-alcanes, nC6 à nC9, sur des zircones sulfatées modifiées par les métaux, platine, iridium ou palladium, avec pour principal objectif la compréhension des mécanismes réactionnels. Malgré le caractère bifonctionnel des catalyseurs, la transformation des alcanes ne suit pas le mécanisme bifonctionnel classique. Nos résultats suggèrent plutôt un mécanisme faisant intervenir un site actif unique, l'adduit métal-proton [(H-Mm)(Hx)x+], et une étape d'adsorption associative. Cet adduit regroupe les sites métallique et acide. Toutes les étapes de la réaction se déroulent en une seule adsorption de la molécule sur la fonction métallique. L'espèce adsorbée est une espèce agostique, pour laquelle un atome d'hydrogène, d'un groupe C-H de la chaîne alkyle, est lié, de manière covalente, simultanément à un atome de carbone et à un métal de transition. Ce mécanisme bifonctionnel particulier est confirmé par des études cinétiques, qui, par ailleurs, révèlent un effet de la pression d'hydrogène sur la réactivité des catalyseurs. Avec l'élévation de la pression d'hydrogène, mais aussi avec celle de la température de réaction, a lieu un passage d'une catalyse bifonctionnelle à une catalyse acide. Ce mécanisme s'applique aussi aux catalyseurs bimétalliques à base de platine, où le second métal implique un effet électronique et une ségrégation superficielle, entraînant, respectivement, des modifications de la densité électronique du platine et du nombre d'adduits. Le traçage isotopique au carbone 13 apporte des informations sur les mécanismes d'isomérisation. Ces réactions se déroulent préférentiellement selon un processus en une étape faisant intervenir des intermédiaires cyclopropanes protonés. Néanmoins, la structure cristalline monoclinique semble favoriser les processus répétitifs. Par ailleurs, cette technique au 13C peut aussi fournir des renseignements pour l'évaluation de l'acidité de catalyseursIsomerization reactions of n-alkanes, from nC6 to nC9, on sulphated zirconia supported platinum, iridium, or paladium, catalysts are described in this work, the aim being to contribute to better understand the mechanisms through which those reactants are rearranged. Despite the bifunctional character of the catalysts, the alkane transformation is not explained by the classical bifunctional mechanism. Our results are rather in favour of a metal-proton adduct model [(H-Mm)(Hx)x+], and an associative adsorption step. This adduct gathers the metallic and the acidic sites. All the reaction steps are achieved during a single residence of the molecule on the metallic function. The adsorbed species is an agostic species, for which a hydrogen atom, of a C-H bond of an alkyl group, is covalently bonded both to a carbon atom and to a transition metal atom. This particular bifunctional mechanism is confirmed by kinetic studies, which, moreover, display a hydrogen pressure influence on the catalysts reactivity. A transition from bifunctional catalysis to acid catalysis occurs with the increase of hydrogen pressure and with the enhancement of the reaction temperature
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Choi, Adam. "Illuminating Biology with Membrane Penetrating Sulfonate Delivery Scaffolds and Near-Infrared Azasiline Fluorophores." eScholarship@UMMS, 2018. https://escholarship.umassmed.edu/gsbs_diss/997.
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Near-infrared (NIR) light, with wavelengths of 650 to 900 nanometers, effectively penetrates tissues. The high signal to noise ratio and low phototoxicity of NIR light makes this wavelength range ideal for deep tissue imaging. However, current NIR fluorophores are generally large hydrophobic molecules that are prone to aggregation. Sulfonation can enhance aqueous solubility, but their anionic nature prevents membrane diffusion, and thus, restricts the applications of sulfonated molecules to in vitro or fixed cells.
The repertoire of commercially available sulfonated NIR probes is mostly limited cyanines, which have low photostability. Moreover, larger cyanines require multiple sulfonates to maintain aqueous solubility. For example, Indocyanine Green is only sparingly soluble in PBS, despite having two sulfonates.
My work has focused on the delivery of sulfonated dyes into live cells and the development of a new, ultra-compact NIR dye scaffold. First, to expand the in-cell applications of sulfonated fluorophores, I designed reductively-labile sulfonate protecting groups. Using these scaffolds, I have successfully delivered the fluorophore dansyl sulfonate into live cells, where the cytosolic reducing environment unmasks the anionic sulfonate. Secondly, to create a compact, photostable NIR fluorophore, I pioneered the discovery of azasilines dyes. The two azasiline derivatives, ASiFluor710 and ASiFluor730, fluoresce over 700 nanometers and are among the most compact NIR fluorophores currently known. ASiFluor730 also retains the high photostability of oxazine dyes, highlighting their potential in long exposure applications. Beyond the immediate applications in fluorescence microscopy and in vivo imaging, I envision that my work will serve as a framework for the future design of soluble, membrane permeable, NIR fluorescent probes.
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Martin, Isabelle. "Développement d'une matrice à base d'aluminate de calcium pour la cimentation de boues issues de la décontamination d'effluents actifs." Thesis, Toulouse 3, 2016. http://www.theses.fr/2016TOU30186/document.
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L'industrie nucléaire est une industrie génératrice de déchets, dont certains sont radioactifs. Ces déchets radioactifs ont des formes et des origines diverses, allant de la paire de gant de manutention faiblement contaminés, à la suspension aqueuse de produits de fissions hautement radioactifs. Dans ce travail, un type de déchet bien particulier a été étudié ; des boues issues de la décontamination d'effluents liquides radioactifs, possédant entre autres les trois particularités suivantes ; * Etre moyennement radioactif, selon les critères de l'ANDRA. * Etre composé d'une forte teneur en eau de constitution (ne pouvant être retirée par simple évaporation) ; * Etre composé d'un sorbant (PPFeNi) dont la stabilité chimique n'est pas assurée pour un pH supérieur à 11. Ces particularités font qu'un enrobage dans une matrice minérale forte consommatrice d'eau, et bas-pH (pH < 11) est envisageable. Le choix c'est alors porté sur le développement d'une matrice ettringitique réalisée à partir d'un mélange de Ciment d'Aluminate de Calcium (CAC) et de sulfate de calcium. Dans un premier temps, la stabilité du sorbant du césium utilisé dans cette étude a été testée dans différents environnements de pH (2 à 14) et de température. Pour cela des analyses chimiques de solution ainsi que des caractérisations du composé par diffraction de rayons X, FTIR et microscopie électronique à balayage-EDS ont permis de fixer les bornes de stabilité que la formulation ettringitique doit avoir. Puis une étude microstructurale (nature et morphologie des produits) de mélanges ettringitiques binaires CAC/sulfate de calcium type hémihydrate et/ou anhydrite a été effectuée afin de caractériser la stabilité de l'ettringite, hydrate fort consommateur d'eau. Les propriétés bas-pH ont été vérifiées notamment par analyse chimique de solutions porales. Certaines limites de ces systèmes concernant le dégagement de chaleur et la possible formation de systèmes expansifs ont été mises en évidence. L'effet de l'augmentation du rapport eau/liant, responsable d'un effet de dilution et permettant de réduire les deux effets précédents, a été également regardé pour ces systèmes binaires. Afin de réduire la chaleur dégagée à court terme tout en permettant le développement de l'hydratation à long terme de systèmes ettringitiques, ces systèmes binaires ont été substitués par des additions minérales à hydraulicité latente type laitier de haut fourneau. Une étude microstructurale de la réactivité du laitier et de la modification de l'assemblage ettringitique a montré une réactivité modérée de ce dernier à jeune âge conformément aux attentes. Pour favoriser sa réactivité à long terme par activation alcaline/sulfatique différentes proportions de sulfate de calcium à dissolution plus lente ont été testés. Les caractéristiques microstructurales de ces systèmes ternaires en présence de différentes teneurs en eau intrinsèquement liée à la nature de type boue du déchet a été étudiée. Enfin, les différentes informations sur l'effet des paramètres de formulation obtenues ont débouché sur la mise en place de tests sur des formulations contenant un déchet simulé inerte et enrichi en chlorures. Des essais systématiques de fluidité, de résistances mécaniques et pour certains d'entre eux d'expansion et de dégagement de chaleur doivent permettre d'identifier une série de mélanges adaptés au test à l'échelle de prototype industriel pour la cimentation de bouesNuclear industry generated waste including radioactive wastes, which have different forms and origins. The wastes produced by reprocessing of nuclear fuel are characterized by important water content, by high pH and temperature sensitivity. The cementation in ettringite systems might be a promising solution to solidify radioactive wastes. Mixtures of Calcium Aluminate Cement (CAC) and calcium sulfate are planned to be used, instead of Ordinary Portland Cement (OPC), to form a significant amount of ettringite able to catch water molecules when forming. Moreover, due to the low pH of CAC-based matrices, the latter have a good compatibility with the compounds used to stabilize active elements. Initially, the stability of the sorbent of cesium used in this study was tested in different pH environments (2 to 14) and temperature. Chemical analysis and different microstructural characterizations like X-ray diffraction, FTIR and SEM-EDS have allowed to set stability limits of ettringite systems. Then microstructural study on binary systems composed by mixture of CAC/calcium sulfate (hemihydrate and/or anhydrite) was realized to characterize ettringite stability during the time of hydration. Low pH properties were checked by chemical pore solutions analysis. However, the heat generated by hydration and the possible formation of expansive systems require an increase of e/s ratio and additional components like Ground Granulated Furnace Slag (GGBS). These two parameters were studied subsequently. Microstructural study of GGBS reactivity and the modification of ettringite assemblage were showed that GGBS act as filler at early time of hydration. To promote the GGBS reactivity at long term of hydration by alkaline and sulfate activation, different nature of calcium sulfate was used. Then the microstructural characteristic of this ternary system in presence of different e/s ratio was studied. Finally, different information on the effect of formulation parameters obtained led to the development of tests on formulations containing an inert simulated waste and enriched in chlorides. Systematic tests of fluidity, mechanical strength and for some expansion and heat generation should identify a series of mixtures adapted to test prototype to industrial scale for cementing wastes
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Badami, Anand Shreyans. "Morphological and Structure-Property Analyses of Poly(arylene ether sulfone)-Based Random and Multiblock Copolymers for Fuel Cells." Diss., Virginia Tech, 2007. http://hdl.handle.net/10919/29469.
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The commercialization of proton exchange membrane (PEM) fuel cells depends largely upon the development of PEMs whose properties are enhanced over current perfluorinated sulfonic acid PEMs. Understanding how a PEMâ s molecular weight and morphology affect its relevant performance properties is essential to this effort. Changes in molecular weight were found to have little effect on the phase separated morphologies, water uptake, and proton conductivities of random copolymers. Changes in block length, however, have a pronounced effect on multiblock copolymers, affecting surface and bulk morphologies, water uptake, proton conductivity, and hydrolytic stability, suggesting that multiblock copolymer PEM properties may be optimized by changes in morphology.
A major goal of current proton exchange membrane fuel cell research involves developing high temperature membranes that can operate at ~120 °C and low humidites. Multiblock copolymers synthesized from 100% disulfonated poly(arylene ether sulfone) (BPSH100) and naphthalene polyimide (PI) oligomers may be an alternative. At block lengths of ~15 kg/mol they displayed no morphological changes up to 120 °C or even higher. Water desorption was observed to decrease with increasing block length. The copolymers exhibited little to no water loss during a 200 °C isotherm in contrast to random BPSH copolymers and Nafion. A BPSH100-PI multiblock copolymer with large block length appears to have morphological stability and retain water at temperatures exceeding 120 °C, suggesting its candidacy as a high temperature PEM.
A growing number of alternative PEM research efforts involve multiblock copolymer chemistries, but little emphasis is placed on the methods used to couple the oligomers. Fluorinated linkage groups can help increase block efficiency during coupling, but their effect on a PEM is not well-known. The choice of linkage type, hexafluorobenzene (HFB) vs. decafluorobiphenyl (DFBP), appears to have small but observable influences on multiblock copolymers with disulfonated and unsulfonated poly(arylene ether sulfone) oligomers. DFBP linkages promote greater phase separation than HFB linkages, resulting in increased stiffness, decreased ductility, and increased proton conductivity at low humidities. DFBP linkages also promote more surface enrichment of fluorine, causing changes in surface morphology and slightly increased water desorption, but determining the impact on actual fuel cell performance requires further research.Ph. D.
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Ohnenstetter, Daniel. "Minéralisations associées aux complexes mafiques-ultramafiques en domaine océanique et continental." Nancy 1, 1990. http://docnum.univ-lorraine.fr/public/SCD_T_1990_0539_OHNENSTETTER.pdf.
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Ce mémoire de thèse comporte deux parties: l'une sur les ophiolites et l'autre sur les minéralisations de divers complexes basiques-ultrabasiques, dont les ophiolites, les komatiites et les sills archéens et protérozoïques. Les travaux sur les ophiolites ont abouti à deux résultats majeurs : 1) la reconstitution du puzzle ophiolitique corse ; 2) la diversité des ophiolites avec une classification en deux grands types, dont le magmatisme de l'un s'apparente à celui des rides médio-océaniques, tandis que le magmatisme de l'autre ressemble à celui des arcs immatures. Des études sur la minéralisation des corps basiques-ultrabasiques, il ressort que la nature des magmas parentaux est importante pour juger de leur potentialité métallogénique (Cr, Ni, éléments du groupe du platine EGP). Le caractère saturé à sursaturé des magmas basiques a été noté dans les ophiolites porteuses de gisements de chrome, dans les lopolites stratifiés enrichis en Cr, EGP. Des magmas de type boninitiques seraient à l'origine de certains de ces complexes. En conclusion de la thèse est présentée une classification des complexes basiques-ultrabasiques basées sur l'ordre de cristallisation des minéraux qui permet de discuter de l'origine des gisements des EGP par rapport à celle des autres minéralisations (chromite, concentration sulfurées).
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Soldera, Armand. "Synthese et caracterisation de nouveaux composes smectiques c* ferroelectriques contenant un cur rigide de type tolane et un groupe sulfinate chiral." Université Louis Pasteur (Strasbourg) (1971-2008), 1992. http://www.theses.fr/1992STR13032.
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Ce present travail porte sur la synthese et la caracterisation des premiers cristaux liquides smectiques c* chiraux ferroelectriques contenant un groupe sulfinyle comme centre chiral et un groupement tolane comme partie constitutive du corps rigide. L'adjonction d'un second centre chiral de configuration unique voisin du premier, permet la separation des deux diastereomeres, obtenus ainsi optiquement purs. On observe un polymorphisme liquide cristallin different selon la configuration absolue du soufre. Une purification poussee par hplc preparative des deux epimeres montre une contradiction apparente entre la structure telle qu'elle peut etre deduite d'observations au microscope et celle determinee par diffraction des rayons x. Des mesures de la polarisation spontanee macroscopique, effectuees sur des melanges de deux diastereomeres, conduisent a des valeurs de p#s de l'ordre de 50 a 70 nc/cm#2. Ce travail ouvre la voie au developpement de nouveaux cristaux liquides smectiques c* ferroelectriques comportant de nouvelles sources de chiralite
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Harper, Matthew P. "Platinum Group Element Mineralization in "Ballrooms" of the J-M Reef of the Stillwater Complex, Montana." Diss., CLICK HERE for online access, 2004. http://contentdm.lib.byu.edu/ETD/image/etd442.pdf.
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Pollet, Pamela. "Métallation ortho-dirigée par des groupes sulfures en série diazinique. Synthèses de sulfoxydes chiraux et étude de l'induction asymétrique de ces groupes en série aromatique π-déficitaire." Rouen, 1998. http://www.theses.fr/1999ROUES028.
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La synthèse de nouveaux dérivés sulfurés diaziniques : sulfanyl, sulfinyl, sulfonyldiazines, sulfonamides ainsi que celle d'un dérivé phosphoré de la pyridazine a été tout d'abord réalisée. Ces dérivés ont été métallés et divers électrophiles ont été utilisés. La métallation des sulfoxydes chiraux synthétisés auparavant a permis dans certains cas une induction asymétrique totale lors de la réaction avec des aldéhydes prochiraux. Cette diastéréoselectivité a été étudiée et analysée.
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Matson, Johan. "Coffee grounds as an adsorbent for heavy metals in water treatment : Study based on the environment around Vattenriket, Kristianstad." Thesis, Linnéuniversitetet, Institutionen för biologi och miljö (BOM), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-96299.
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One of the modern times worst environmental problem are polluted water resources. An example of source of pollution to water resources are, heavy metal leached from acid sulfate soils (ASS). When these soils are stable, which they are if they are left underwater in an anoxic environment (for example below the water table), they are often sought after since they consist of high amount of nutrients which farmers use as farmlands. ASS is therefore created when farmers drain their land and the sulfide soil gets exposed to air, resulting in its oxidation and therefore formation of sulfuric acid. In a previous study performed by scientists from Linnaeus University, it was concluded that a natural reserve located in Vattenriket, Kristianstad was possibly damaged by the drainage discharge of an adjacent acid sulfate soil. For remediation of acid sulfate soil, notably removal of metals from drainage waters, grounded coffee has been suggested to be able to perform well as an adsorbent. This study was performed to investigate how well grounded coffee could be used as an adsorbent, for calcium (Ca) and zinc (Zn), from water samples collected in Vattenriket, Kristianstad. It was also studied to see if grounded coffee could be cleaned using a sodium hydroxide solution to increase its adsorption capacity. To be able to evaluate how well it could be used as an adsorbent, it went through two different cleaning procedures and total organic carbon and pH readings was performed. The used method for this paper was to clean the grounded coffee in two different stages. The first stage consisted of using distilled water and letting it run through the residues until the water came out as transparent. Cleaning using a NaOH solution consisted of suspending the residues in a NaOH solution for 45 minutes and swapping the solution 6-8 times. After the grounded coffee had dried in an oven at 30o for 48 hours, it was put into different fraction sizes, weighed and bagged. The water samples then had to be filtered using a pump and Filtropur S 0.45 filters. Lastly, 45 falcon tubes containing 15 different amounts of grounded coffee had 50 ml of filtered water sample added to them. For analysis, atomic absorption spectroscopy was used. The results showed that the maximum amount of adsorbed calcium was achieved at 1.5g of grounded coffee in a 50 ml water solution which managed to adsorb 99.53% of calcium. The maximum amount of adsorbed zinc was achieved at 1.25g of grounded coffee in a 50 ml solution which resulted in 99.16% of adsorbed zinc. The study also showed that when the total organic carbon-content was decreasing, due to excessive cleaning, the pH was increasing. This was further proof that the grounded coffee still had residues onto its surface that could inhibit its adsorption capabilities.
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Mattoussi, Nabila. "Assemblages supramoléculaires par complexation moléculaire ou métallique de calix[4]arène fonctionnalisés par des groupes sulfonate et carboxylate : synthèse, cristallisation et détermination des structures cristallines." Thesis, Lyon 1, 2013. http://www.theses.fr/2013LYO10325.
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Le travail présenté concerne la synthèse de calixarènes fonctionnalisés par des groupes sulfonates et carboxylates et l'étude détaillée des structures cristallines de leurs complexes moléculaires ou métalliques avec des métaux 3d et 4f. L'une des préoccupations majeures de ce travail concerne la compréhension des assemblages supramoléculaires dans ces systèmes. Le premier chapitre présente des éléments bibliographiques sur les calixarènes, leur histoire, les différentes conformations et les méthodes principales de fonctionnalisation puis la chimie supramoléculaire associée comprenant les complexes moléculaires et métalliques. Le deuxième chapitre est dédié à une série de complexes moléculaires de type hôte-invité formés entre le para-sulfonatocalix[4]arène (SC4) et différentes bipyridine En continuité avec ce travail nous présentons en suite la structure et les propriétés magnétiques d'un complexe métallique constitué d'un SC4 pontant deux entités dinucléaires de phenanthroline [FeIII2(μ-O)(H2O)5(phen)2] par la coordination des groupes sulfonates. Le troisième chapitre est consacré à la chimie de coordination des calixarènes sulfonatés avec les lanthanides. Nous avons mis en évidence trois types de structures cristallines qui sont toutes des polymères de coordination où les ions lanthanides jouent le rôle d'assembleur des calixarènes par la coordination des groupes sulfonates selon trois types de structure (A, B et C). Nous avons obtenu ces trois structures (A, B et C) pour l'ensemble de lanthanide (La, Pr, Nd , Eu, Gd, Tb, Dy, Ho, Yb). Le quatrième chapitre concerne la chimie de coordination des métaux de transition 3d (Co, Mn, Zn, Cu) avec des calixarènes fonctionnalisés par des groupes carboxylates sur leur partie basse. Avec le calixarène dicarboxylate nous avons obtenu une série de complexes isomorphes dans lesquels deux calixarènes sont coordinés à deux centres métalliques pour former des chaînes infinies. Le cinquième chapitre présente les résultats d'un travail exploratoire visant à synthétiser des azacalix[4]arènes, dans le but de complexer des métaux de transition. L'étude RPE des précurseurs a mis en évidence des espèces radicalairesThis work presents the synthesis of calixarenes functionalized with sulfonate and carboxylate groups and the detailed study of the crystal structures of their molecular or metal complexes with 3d and 4f metals ions. One of the major concerns of this work is the understanding of supramolecular assemblies in these systems. The first chapter gives bibliographic elements on the history, the different conformations and the main methods of functionalization of calixarenes and on their supramolecular chemistry comprising molecular and metal complexes. The second chapter is dedicated to a series of molecular complexes of the host-guest type formed between the para-sulfonatocalix[4]arene (SC4) and various bipyridine. In continuation with this work we then present the synthesis, structure and magnetic properties of a metal complex comprising a SC4 bridging by the sulfonate groups two iron(II) dinuclear entities with coordinated phenathroline [FeIII2 (μ-O)(H2O) 5(phen) 2]. The third chapter is devoted to the coordination chemistry of sulfonated calixarenes with lanthanides. We have found three types of crystal structures which are polymers wherein the lanthanide ion function as an assembler of calixarenes by the coordination of the sulfonate groups along three type of structure (A, B and C). We obtained these three structures (A, B and C) for all lanthanide (La, Pr, Nd, Eu, Gd, Tb, Dy, Ho, Yb). The fourth chapter concerns the coordination chemistry of 3d transition metals (Co, Mn, Zn) with calixarenes functionalized with carboxylate groups on lower rim. With calixarene dicarboxylate we got a series of isomorphic complexes in which two calixarenes are coordinated to two metal centers to form infinite chains. The fifth chapter presents the results of an exploratory work to synthesize azacalix[4]arene with the aim to complex transition metals ions. The EPR study of the precursors has evidenced free radical species
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Ando, Daisuke. "Studies on the novel selective β-O-4 cleavage method of lignins by E1cB type elimination reaction assisted by the sulfone group -γ-TTSA method-." Kyoto University, 2014. http://hdl.handle.net/2433/188762.
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Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第18324号
農博第2049号
新制||農||1021(附属図書館)
学位論文||H26||N4831(農学部図書室)
31182
京都大学大学院農学研究科森林科学専攻
(主査)教授 髙野 俊幸, 教授 西尾 嘉之, 教授 梅澤 俊明
学位規則第4条第1項該当
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El-Batta, Amer Adnan. "Part I, copper(I) iodide dimethyl sulfide catalyzed 1,4-addition of alkenyl groups from alkenylzirconium and alkenylzinc reagents and their application toward the total synthesis of azaspirene ; Part II, aqueous Wittig chemistry employing stabilized ylides and aldehydes." Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2007. http://wwwlib.umi.com/cr/ucsd/fullcit?p3268346.
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Thesis (Ph. D.)--University of California, San Diego and San Diego State University, 2007.Title from first page of PDF file (viewed August 7, 2007). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 265-280).
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Seat, Zoran. "Geology, petrology, mineral and whole-rock chemistry, stable and radiogenic isotope systematics and Ni-Cu-PGE mineralisation of the Nebo-Babel intrusion, West Musgrave, Western Australia." University of Western Australia. School of Earth and Geographical Sciences, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0202.
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The Nebo-Babel Ni-Cu-platinum-group element (PGE) magmatic sulphide deposit, a world-class ore body, is hosted in low-MgO, tube-like (chonolithic) gabbronorite intrusion in the West Musgrave Block, Western Australia. The Nebo-Babel deposit is the first significant discovery of a nickel sulphide deposit associated with the ca. 1078 Ma Giles Complex, which is part of the Warakurna large igneous province (LIP), now making the Musgrave Block a prime target for nickel sulphide exploration. The Musgrave Block is a Mesoproterozoic, east-west trending, orogenic belt in central Australia consisting of amphibolite and granulite facies basement gneisses with predominantly igneous protoliths. The basement lithologies have been intruded by mafic-ultramafic and felsic rocks; multiply deformed and metamorphosed between 1600 Ma and 500 Ma. The Giles Complex, which is part of the Warakurna LIP, was emplaced at ca. 1078 Ma and consists of a suite of layered mafic-ultramafic intrusions, mafic and felsic dykes and temporally associated volcanic rocks and granites. The Giles Complex intrusions are interpreted to have crystallised at crustal depths between 15km and 30km and are generally undeformed and unmetamorphosed.
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Fleischhacker, Ján. "Vliv technologie výroby popílkového pórobetonu na vznik tobermoritických fází." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2016. http://www.nusl.cz/ntk/nusl-240077.
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Autoclaved aerated concrete is long-time ecological building material with usefull properties. There needs to be done research of its mineralogical compound for reengineering the production. The main mineral compound of AAC is tobermorite, it increases its mechanical properties. In the presence study, we examine the usage of nature and artificial silicious materials. Also, we investigate the influence of sulfate and alumina admixtures, as well as fluidized bed combustion ash, which can be used as the lime and gypsum replacement. Closure of the study is design of the optimal raw material composition, also hydrothermal treatment of autoclaved aerated concrete. In relation to its mechanical properties, mineralogical composition and cost.
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Gueddari, Khalid. "Approche géochimique et physico-chimique de la différenciation des éléments du groupe du platine (PGE) et de l'or dans le manteau supèrieur bético-rifain et dans les xénolites de péridotites sous continentales." Université Joseph Fourier (Grenoble), 1996. http://www.theses.fr/1996GRE10031.
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L'etude de la distribution des elements du groupe du platine (pge: ir, ru, rh, pt et pd) et de l'or dans les peridotites des massifs ultrabasiques orogeniques (ronda, beni bousera) permet de mettre en evidence le comportement differentiel de cu, pt et pd par rapport a ni, ir et ru au cours de la fusion partielle. Ce comportement resulte d'une extraction de cu, pt et pd par les liquides silicates sous forme d'une phase sulfuree. A l'inverse, ir et ru restent pieges dans les residus de fusion probablement sous forme de grains refractaires interstitiels. Le rh qui montre un comportement refractaire a ronda contrairement a beni bousera ne peut pas etre attribue a son incorporation dans le spinelle mais suggere plutot des fs#2 plus faibles dans les peridotites de ronda que dans celles des beni bousera. Par ailleurs, la distribution des pge dans les xenolites de peridotite a spinelle des basaltes alcalins (france, sud de l'espagne) est caracterisee par des spectres des teneurs normalisees au manteau relativement plats et ne semble pas etre influencee par le processus de fusion. Elle refleterait une refertilisation ou une retention d'une fraction sulfuree riche en pt et en pd par un manteau plus ou moins deprime, a la suite de multiples extractions basaltiques. Les spectres des teneurs en pge et en au de pente pd/ir positive et variable, couples aux compositions en elements majeurs et en traces, illustrent l'heterogeneite geochimique des pyroxenites des massifs de ronda et des beni bousera. Ces pyroxenites peuvent etre regroupees dans deux lignees distinctes. Une premiere (pyroxenites a grenat s. S. Et pyroxenites a spinelle s. L. ) est caracterisee par un rapport al#2o#3/feotot <2. 7. Les basses teneurs en ir, ru et rh peuvent etre reliees a une precipitation precoce de ces elements en reponse a une augmentation de fo#2 tandis que les teneurs en pt, pd et au sont gouvernees par les sulfures. Certaines similitudes entre les pyroxenites a grenat s. S et les pyroxenites a spinelle s. L. Suggerent un lien genetique entre ces deux facies. La seconde lignee, correspondant a des clinopyroxenites a grenat corindon tres alumineuses (al#2o#3/feotot > 2. 7), montre des niveaux de teneurs tres faibles, ou au contraire, tres riches en pge. La variation des teneurs observee ne concerne que les ppge et l'au et peut etre attribuee a une segregation d'une faible fraction de sulfures.
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Schenck, Charles. "Pollution saline de l'eau souterraine et de l'air liee aux activites economiques en haute alsace : incidences agronomiques." Université Louis Pasteur (Strasbourg) (1971-2008), 1987. http://www.theses.fr/1987STR13220.
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De par ses caracteristiques physiques, la vallee de l'ill en haute alsace est particulierement sensible a la pollution. Dans cette region a vocation industrielle et agricole la contazmination du milieu se traduit par une forte mineralisation de l'eau souterraine et des retombees atmospheriques solubles, diluees mais acides. La composition naturelle: bicarbonatee calcique de l'eau de la nappe phreatique est modifiee par une charge chloro-sodique et nitrique non negligeable. Quant aux retombees, elles provoquent au sol, des apports d'elements mineraux parmis lesquels predominent les chlorures, les sulfates, les nitrates, le calcium, le potassium et le sodium
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David, Marta Edith Velásquez. "Composição isotópica de Pb-Sr e Nd da mineralização de ouro do depósito Córrego do Sítio, Quadrilátero Ferrífero (MG): implicações na modelagem conceitual." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/44/44141/tde-19042007-142433/.
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O Quadrilátero Ferrífero (MG) é uma importante unidade geotectônica do Cráton do São Francisco que alberga jazidas de ferro e ouro hospedadas na seqüência greenstone belt Rio das Velhas e cuja evolução geodinâmica esteve regida por vários eventos tectonometamórficos. Depósitos de ouro gerados por fluidos epitermais e remobilizações orogênicas proterozóicas se associam intimamente com camadas bandas de ferro e raramente disseminados em metapelitos no topo do greenstone. Nas mineralizações é comum uma paragênese que cristalizou mediante diversos processos e em distintos estágios com predomínio de sulfetos de ferro. Em geral os minérios possuem forte controle estrutural por dobras, falhas e cisalhamentos transcorrentes, desenvolvidos durante vários eventos deformacionais de diversa índole e estreita relação com processos de alteração hidrotermal como sericitização, carbonatação, cloritização, entre outros de menor incidência. O depósito de ouro Córrego do Sítio hospeda-se na seqüência silisiclástica de origem turbidítica metamorfisada em fácies xisto verde denominada Associação de Litofácies Ressedimentada que faz parte do Grupo Nova Lima, se apresenta disseminado em metapelitos e em veios de quartzo com carbonato. A mineralização que acompanha o ouro cristalizou em vários estágios principais nos que predominaram (i) pirita + pirrotita, (ii) arsenopirita + pirrotita + pirita com texturas finas e orientadas, (iii) arsenopirita com pirrotita e sulfosais em veios de quartzo, (iv) pirita grossa pervasiva em todas as rochas hospedeiras. O estudo da composição isotópica Pb, Sr e Nd, permitiu identificar que as fontes dos fluidos mineralizantes foram as rochas hospedeiras, que na evolução policíclica da mineralização participaram eventos metamórficos e hidrotermais a 2.2, 2.0 Ga. e sobreimpostos a ~600 Ma. os quais induziram os processos de circulação hidrotermal na área de estudo. Mediante comparativa com outros depósitos da região, sugere-se que os metais formadores do minério depositaram-se em Córrego do Sítio à idade de 2.2 Ga. originados a partir da BIF tipo São Bento e remobilizados por fluidos através de falhas inversas. Análises geocronológicas U-Pb (SHRIMP) e K-Ar embora não decisivos em quanto à determinação da idade da mineralização, revelaram a idade de ~2.7 Ga. como o limite temporal para a deposição das rochas hospedeiras. No contexto geológico aplicado se estabelece a potencialidade para a prospecção aurífera que apresentam as rochas metapelíticas do topo do Greenstone Belt Rio das Velas associadas a camadas bandadas de ferro com ouro, e que os alvos mais relevantes seriam zonas com falhas inversas e cisalhamentos transcorrentes.The Quadrilátero Ferrífero is an important geotectonic unit of the São Francisco Craton that host iron and gold deposits within the vulcanosedimentary rocks of the greenstone belt Rio das Velhas. The geodynamic evolution of this greenstone includes several tectonometamorphic events. Gold deposits were formed by epithermal fluids, remobilized during the Proterozoic orogenic processes, are associated whit the banded iron formations and are sporadically disseminate in metapelitic rocks within the top of the greenstone sequence. In the ores is common the crystallization of iron sulfide minerals during diverse stages. Gold deposits have an important structural control by folds, reverse faults and strike-slip shearing zones, and are commons several hydrothermal alteration processes like sericitization, chloritization and carbonate usually related to the deformation. The Córrego do Sítio gold deposit is hosted in turbiditic siliciclastic rocks that are metamorphosed in the greenschist facies. The gold is associated with the iron sulfide arsenopyrite and pyrite, which are disseminated in metapelitic rocks and quartz-carbonate veins. The mineralization includes vary stages of crystallization, (1) pyrite and pyrrotite (2) arsenopyrite, pyrrotite and fine pyrite, (3) arsenopyrite whit pyrrotite and sulphosalts in quartz vein, and (4) pervasive pyrite. An integrated Pb, Sr e Nd, isotopic study of the Córrego do Sítio deposit allowed to identify that sources of the mineralizing fluids was the host rocks, that in the policiclic evolution the gold mineralizaton had participation events of metamorphism and hidrothermalism to age 2.2, 2.0 and 0.6 Ga. respectively the wich induced the hydrothermal circulation processes in the study area. The isotopic character of this deposit and its comparison with similar ones, suggest that the gold and its metals associated it is deposited in Córrego do Sítio to age 2.2 Ga. and that metals were derived from the banded iron formations, and remobilized by hidrothermal fluids across reverse faults. Although U-Pb (SHRIMP) and K-Ar geochronologic data were not conclusive to constrain the age of the mineralization, they provide to age ~2.7 Ga. that a good limit for the sedimentation of the host rock. It is suggest that there is a potential for gold prospection within the metapellitic rocks associated with banded iron formation of the Greenstone Rio das Velhas, and that the more relevant targets include areas with inverse and strike-slip fault.
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Madi, Atman. "Géologie de la partie nord de l'ophiolite d'Oman : pétrologie et géochimie de la séquence plutonique du massif de Fizh." Phd thesis, Grenoble 1, 1995. http://www.theses.fr/1995GRE10061.
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La séquence plutonique du massif de Fizh (partie nord de l'ophiolite d'Oman) offre une complexité crustale, liée à une diversité des corps magmatiques et du système filonien. La cartographie détaillée montre une succession d'événements magmatiques dont les séries principales sont formées de gabbros lités, des wehrlites et pyroxénites, des gabbronorites. Le magmatisme gabbroïque est généré dans une grande chambre magmatique axiale, alors que le magmatisme wehrlitique est dit hors-axe ; ceci est conditionné par la segmentation axiale de la paléodorsale. L'asymétrie ainsi observée dans la séquence crustale est marquée par la distribution et l'abondance des corps ultrabasiques. Les variations longitudinales dans les séquences stratigraphiques montrent des discontinuités au sein de la paléodorsale dans ce massif. Les granitoïdes sous forme de filons ou de stocks, attestent une succession d'événements magmatiques et les modalités de l'accrétion. En effet, les plagiogranites sont liés à la cristallisation fractionnée des gabbros, au cours de l'épisode d'accrétion normale. Les granodiorites et les diorites quartziques sont rattachées spatialement aux ultrabasites et formées par cristallisation fractionnée pendant la phase d'écaillage intra-océanique. Les granites et les leucogranites sont tardifs et à cachet collisionnel. Ils sont issus de la fusion partielle de la semelle métamorphique et liés à l'épisode obductif chaud. Les gisements de chromite sont variés et sont localisés dans le manteau et à la limite manteau-croûte. Les concentrations de chromite dans les ultrabasites sont importantes et présentent un effet sur le comportement des éléments du groupe du platine. Les sulfures magmatiques (pentlandite et chalcopyrite) précipitent dans les wehrlites et les pyroxénites en même temps que le plagioclase. Le comportement des PGE dans les chromitites montre qu'elles sont moins différenciées que celles des autres massifs ophiolitiques. Les PPGE et particulièrement le Pd précipitent dans les ultrabasites en même temps que les sulfures d'origine magmatique
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LeeMing-Chuan and 李明川. "Competitive reaction kinetics of microbial groups in expanded granular sludge bed reactors treating sulfate-containing wastewater." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/40906635843514219683.
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碩士崑山科技大學
環境工程研究所
95
To examine the competitive-reaction kinetic behavior of sulfate-reducing bacteria (SRB) and methanogenic bacteria (MB) in expanded granular sludge bed (EGSB) reactors treating sulfate-containing wastewater, four identical EGSB reactors (with acetate as a feed substrate) were used. The two EGSB reactors were respectively used to enrich SRB and MB, and thereby the break-up granules (dispersed sludge) can be used to determine intrinsic and apparent biokinetic parameter values of SRB and MB. The other two EGSB reactors were used to proceed with Phase I and II experiments treating sulfate-containing wastewater. Thus, not only water quality data and granule characteristic parameters (granule diameter, microbial density, and biomass) can be obtained, but the mass fractions of SRB and MB (fSRB, fMB) for each test run of the EGSB reactors also be estimated by mixing break-up granules obtained from the experimental system with that obtained from the enrichment system at various proportions. In phase I experiment, the two EGSB reactors were maintained at the organic loading rate (OLR) of 4.0 kg COD/m3-d) but with six different influent COD/SO42- ratios (0.5, 0.8, 1.1, 1.3, 1.8, and 3.0). Phase II experiment proceeded immediately following the last test run of phase I experiment [i.e., the influent COD/SO42- ratios of 1.1 (SRB was a predominant microbial group) and 3.0 (MB was a predominant microbial group)] but with successive increasing OLRs from 4.0 to 6.0, 6.3, 6.8, 7.2, 7.6, 8.0, 8.3, 8.7 and 9.0 kg COD/m3-d. Taking account of inhibiting effects of free H2S on SRB and MPB, a kinetic model for EGSB reactors treating sulfate-containing wastewater was also developed and validated by experiments. When the EGSB reactors were maintained at the OLR of 4.0 kg COD/m3-d but with six different influent COD/SO42- ratios (0.5, 0.8, 1.1, 1.3, 1.8, and 3.0), the concentrations of sulfide (77–564 mg S/L) and free H2S (40–293 mg S/L) in the effluent decreased with increasing influent COD/SO42- ratio and the acetate removal efficiency achieved greater than 98.5%, showing that sulfide/H2S did not impose an inhibiting effect on microbial groups. Meanwhile, the average granule diameter (dp) slightly decreased with increasing influent COD/SO42- ratio; fSRB decreased with increasing influent COD/SO42- ratio whereas fMB increased with increasing influent COD/SO42- ratio. It was also found that SRB became a predominant microbial group when the influent COD/SO42- ratio was maintained at less than/equal to 1.3, whereas MB became a predominant microbial group when the influent COD/SO42- ratio was maintained at greater than/equal to 1.8. By using the performance data and the mass fractions of SRB and MB together with a stoichiometric chemical equation, the calculated specific substrate utilization rate of SRB (0.39–0.62 mg acetate/mg VSS-d) was lower than that of MB (0.57–1.01 mg acetate/mg VSS-d). When the EGSB reactors were maintained at the influent COD/SO42- ratios of 1.1 (SRB was a predominant microbial group) and 3.0 (MB was a predominant microbial group) but with increasing OLR from 4.0 to 6.0, 6.3, 6.8, 7.2, 7.6, 8.0, 8.3, 8.7 and 9.0 kg COD/m3-d, the acetate removal efficiency still achieved 96.1–97.9% and 94.9–98.9%, respectively, disclosing that H2S (286–368 mg S/L) in the bulk liquid did not impose a significant inhibiting effect on SRB and that H2S (88–123 mg S/L) in the bulk liquid also did not impose a significant inhibiting effect on MB. However, with a further increase in OLR (8.7 kg COD/m3-d), the acetate removal efficiency of the EGSB reactor with the predominant microbial group of SRB declined to 80.5%, implying that H2S (429 mg S/L) in the bulk liquid imposed a significant inhibiting effect on SRB. With a further increase in OLR (9.0 kg COD/m3-d), the acetate removal efficiency of the EGSB reactor with the predominant microbial group of MB still achieved 94.1–97.8%, revealing that H2S (128–140 mg S/L) in the bulk liquid did not impose an inhibiting effect on MB. Meanwhile, with an increase in OLR, granule’s specific gravity, dp, microbial density, and biomass increased but fSRB and fMB varied slightly. By comparing the obtained intrinsic and apparent biokinetic parameters of SRB with those of MB, kSR (1.99 mg acetate/mg VSS-d) and kSR’ (1.74 mg acetate/mg VSS-d) were higher than kM (1.57 mg acetate/mg VSS-d) and kM’ (1.30 mg acetate/mg VSS-d); if acetate was growth-limiting for both SRB and MB, Ks,M (10 mg acetate/L) and Ks,M’ (15 mg acetate/L) were lower than Ks,a (27 mg acetate/L) and Ks,a’ (30 mg acetate/L), implying that the affinity of acetate to MB was greater than that to SRB; KI,M (263 mg H2S/L) and KI,M’ (429 mg H2S/L) were lower than KI,SR (289 mg H2S/L) and KI,SR’ (557 mg H2S/L), implying that free H2S imposed a greater inhibiting effect on MB. Finally, by inserting operating conditions and biological and physical parameter values into the kinetic model, the calculated acetate removal efficiency was only 11.6% deviated from the experimental acetate removal efficiency. Accordingly, the proposed kinetic model can be used to predict the treatment performance of EGSB reactors appropriately.
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Ingram, Laura Jane. "The Synthesis of Sulfated Carbohydrates Using a Sulfate Protecting Group Strategy." Thesis, 2010. http://hdl.handle.net/10012/5437.
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Sulfated carbohydrates play key roles in a wide range of biological processes such as blood clotting, viral entry into cells, amyloidogenesis, neurite outgrowth, tumor growth and metastasis. However, their synthesis still remains a considerable challenge. A general approach to the synthesis of sulfated carbohydrates was examined in which sulfate group is incorporated at the beginning of the syntheses as a protected sulfodiester. Towards this end, a series of sulfuryl imidazolium salts (SIS), a new class of sulfating agents, was prepared and examined as reagents for incorporating 2,2,2-trichloroethyl-protected sulfate esters into monosaccharides. The SIS that contained a 1,2-dimethylimidazolium moiety proved to be a superior sulfating agent compared to SIS bearing no alkyl groups or bulkier alkyl groups on the imidazolium ring. Difficult O- and N- sulfations that required prolonged reaction times and a large excess of the SIS bearing a 1-methylimidazolium group were achieved in high yield and in less time when employing less than half the 1,2-dimethylimidazolium derivative. Efforts were then made to apply the sulfate protecting group strategy to the total synthesis of a class of chondroitin sulfate glycosaminoglycans. These studies revealed some of the limitations of the sulfate protecting group approach to the synthesis of sulfated oligosaccharides. Studies on the selective introduction and isomerization of the carbobenzyloxy protecting group into 2,3-diols of 4,6-O-benzylidene galactose derivatives are also reported.
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González, Martín Rubén. "N-Butane isomerization catalyzed by hydroxyl groups on sulfated zirconia." 1995. http://catalog.hathitrust.org/api/volumes/oclc/34681804.html.
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Thesis (Ph. D.)--University of Wisconsin--Madison, 1995.Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 176-192).
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"Biosignature storage in sulfate minerals- synthetic and natural investigations of the jarosite group minerals." UNIVERSITY OF MONTANA, 2010. http://pqdtopen.proquest.com/#viewpdf?dispub=3369197.
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XU, LAI, and 徐賚. "Reversal Glycosylation with Sulfonate Leaving-Group in Glycosyl Acceptor." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/ggw4b3.
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碩士輔仁大學
化學系
105
Part 1: A reversal glycosylation method is proposed to introduce a sulfonate group at the sugar receptor and a hydroxyl group at the anomeric carbon of the saccharide. The sulfonic acid ester group of the sugar receptor is catalytically converted to the saccharide body by alkaline or acidic conditions, the leaving group is constructed, followed by a basic or acidic catalyzed glycosylation. Part 2: Try to use monosaccharides with simple protection to connect with diol and unsubstituted pyridine at anomeric carbon, selectively generate carbohydrate- Modified 1- (Substituted alkyl)-2 (1H) Pyridones.
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White, Christopher. "Low-sulfide PGE-Cu-Ni Mineralization from Five Prospects within the Footwall of the Sudbury Igneous Complex, Ontario, Canada." Thesis, 2012. http://hdl.handle.net/1807/32849.
Full textAbstract:
North Range low-sulfide mineralization is dominantly hosted by Sudbury breccia, with amphibole-plagioclase equilibrium metamorphic temperatures of 440 to 533 ± 75oC, produced by the SICs thermal aureole. Mineralization led to increases in the bulk halogen content of the host Sudbury breccia and the formation of Ni-enriched ferromagnesian silicates. South Range low-sulfide mineralization is typically hosted by metabasalts of the Huronian Supergroup. Garnet-biotite-plagioclase-quartz geothermobarometry produced equilibrium metamorphic conditions of 513 to 645 ± 50oC and 2.0 to 7.7 ± 1.0 kbar, probably corresponding to a late-Penokean overprint of peak Blezardian/Penokean metamorphism. Silicates associated with South Range mineralization are compositionally similar to the host rock equivalents and no alteration selvage is commonly observed due to subsequent recrystallization.
Platinum-group minerals (PGM) from the North Range comprise platinum and palladium tellurides and bismuth-tellurides, with Sb-bearing palladium bismuth-tellurides and sperrylite from the South Range. Kotulskite-sobolevskite from the North Range shows a previously unreported Ag-Pd substitution, with michenerite from irregular veinlet style mineralization showing the substitution of Se and Sb for Bi. Two unknown PGMs were identified from the South Range, along with kotulskite-sobolevskite-sudburyite crystals displaying extensive Te-Bi-Sb solid-solution not noted before at Sudbury. A new Se-bearing variant of pilsenite was identified at McKim. Polyphase aggregates from both Ranges indicate that Bi-Te melts may have been widespread at some stage postdating the emplacement of the main magmatic sulfides.
Normalized plots for low-sulfide mineralization show enrichments in the precious and semimetals relative to contact and sharp-walled vein mineralization. This enrichment has resulted in elevated concentrations of Ag and Se in chalcopyrite and Pd+Ag and Se in pentlandite from the North Range. The mass balance for North Range samples found that a significant fraction of Ag and Se occurs in sulfides with all other elements preferring discrete phases. A substantial fraction of Pd is hosted by pentlandite on the South Range, with gersdorffite also a major host despite its low abundance. The enrichments observed reflect the formation of low-sulfide mineralization from a fractionated sulfide liquid and hydrothermal fluids that have interacted with a fractionated sulfide source, and suggest that the precious and semimetals behave incompatibly with crystallizing sulfide.
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Cai, Jie-Cheng, and 蔡傑丞. "Synthesis and Properties ofα-Methylstilbene Based Aryl Ether Sulfone Copolymers Containing Sulfuric Acid Group." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/44655600334275864318.
Full textAbstract:
碩士國立成功大學
化學工程學系碩博士班
93
A designed series of directly copolymerized homo- and disulfonated copolymers containing controlled degrees of pendant sulfonic acid groups have been synthesized via nucleophilic step polymerization. Novel sulfonated poly (arylene ether sulfone) copolymers using α-methylstilbene (HMS), with dichlorodiphenyl sulfone (DCDPS) and 3,3’-disodiumsulfonyl-4,4’-dichlorodiphenylsulfone (SDCDPS) were investigated. Molar ratios of DCDPS and SDCDPS were systematically varied to produce copolymers of controlled compositions, which contained up to 70 mol% of disulfonic acid moiety. The goal is to identify thermally, hydrolytically, and oxidatively stable high molecular weight, film-forming, ductile ion conducting copolymers, which had properties desirable for proton exchange membranes (PEM) in fuel cells. The sulfonated copolymers were prepared in the sodium-salt form and converted to the acid moiety and subsequently investigated as proton exchange membranes for fuel cells. Hydrophilicity increased with the level of disulfonation, as expected. Moreover, water sorption increased with increasing mole percent incorporation of SDCDPS. The copolymers’ water uptake depended on both bisphenol structure and degree of disulfonation. Furthermore, the acidification procedures were shown to influence the Tg, water uptake, and conductivity of the copolymers. Proton conductivities for the sulfonated copolymers, under fully hydrated conditions, were a function of bisphenol structure and degree of sulfonation. A careful balance of copolymer composition and acidification method was necessary to afford films which can be both ductile and proton conductive. The copolymers of optimum design yielded conductivities of 0.1 S/cm or higher, which were comparable to those of commercial polyperfluorosulfonic acid films (Nafion™ ).
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LIN, JIN-QUE, and 林金雀. "Studies on the synthesis and properties of contain sulfone and benzimideazole groups of polyamide-esters, polyamides and polyimides." Thesis, 1992. http://ndltd.ncl.edu.tw/handle/13420994010959252790.
Full text
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van, Eck M. "The geology and lithogeochemistry of the Palaeozoic Seventy Mile Range Group at Mt. Farrenden, Charters Towers, North Queensland, Australia." Thesis, 1994. https://eprints.utas.edu.au/21821/1/whole_vanEckM1994_thesis.pdf.
Full textAbstract:
The Cambra-Ordovician Seventy Mile Range Group
occurs as an east-west trending volcano-sedimentary
sequence which is host to several significant volcanichosted
massive sulphide (VHMS) deposits. In the Mt
Farrenden area the base of the Group is comprised of
the fine sedimentary units of the Puddler Creek
Formation. These continent-derived units were
deposited into a back-arc environment. This Formation
is- overlain conformably by the rhyoli te-dominated Mt
Windsor Volcanics, and by the Trooper Creek Formatioh
with mixed andesitic, volcaniclastic sedimentary and
daci tic units. Whole rock geochemistry of a limited
sample suite supports a subduction-related relatively
low-K calc-alkaline volcanic arc environment for the
latter two Formations. The recognised volcanic
textures are not unequivocal in their support for a
subaerial to subaqueous environment for the Mt Windsor
Volcanics, although there is better evidence for a
deeper water (submarine?) environment for the T,rooper
Creek Formation. The uppermost part of the Group, the
Rollston Range Formation, is not represented here.
In the Mt Farrenden area the Sevent:y Mile Range
Group is exposed in a prominent south plunging syncline
which is a major deviation from the otherwise general
east-west trend of the Group. The fold axis contains
the thinnest development of the Mt Windsor Volcanics,
and a part of the largest outcrop area of andesi te
within the Group in the Trooper Creek Formation.
Intrusion of the Black Jack Granodiorite in the
northeast and Policeman Creek Granodiorite in the west
occurred during the Late Silurian-Early Devonian.
Massive, coarsely crystalline bari te occurs in a
small ( 30m by 7m) outcrop at the contact between the
Puddler Creek Formation and the overlying Mt Wirtdsor
Volcanics. The barite may represent the remnants of a
submarine hydrothermal vent of the type associated with
volcanic-hosted massive sulphide deposits. However,
hydrothermal alteration, in general, is very poorly
developed within the study area.
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Aghajanyan, Manuk. "Chemical resistance of lime-based grouts for masonry strengthening." Master's thesis, 2016. http://hdl.handle.net/10198/13178.
Full textAbstract:
The stone masonry walls are present in many buildings and historical monuments, with undeniable asset value, but also in old buildings housing both in Portugal and in Europe. Most of these buildings in masonry are in certain cases in a high state of degradation needing urgent intervention. This requires the identification of deficiencies and the application of appropriate intervention techniques. One of the possible techniques for structural consolidation works of stone masonry walls is the injection of fluid mortars currently called grouts. The choice of grouts is very important with regard in particular to their chemical and physical properties. In this study, carried out under the Master of Chemical Engineering, two types of lime-based grouts were used, in order to evaluate and compare their chemical resistance due to the crystallization of soluble salts. One of the grouts is a pre-dosed blend commercially available, Mape-Antique I from company Mapei (CA), and the second grout is a mixture prepared in the laboratory (LB), comprising metakaolin, cement, hydrated lime, water and superplasticizer. With the purpose of evaluating the action of sulphates on these grouts, a series of samples underwent several wetting-drying cycles using two different temperatures, 20 °C and 50 °C. During the experiment it was determined the change of weight and compressive strength in the analyzed grouts, as well as the sulphate ion concentration and pH of the solution in which the samples were dipped. The commercial grout (CA) apparently has a greater chemical resistance to sulphates. However grout LB showed to have positive results in some parameters.As paredes de alvenaria de pedra estão presentes em muitos edifícios e monumentos históricos, com valor patrimonial inegável, mas também em edifícios antigos de habitação de construção antigos, tanto em Portugal como na Europa. Grande parte destas edificações em alvenaria encontra-se, em certos casos, num elevado estado de degradação pelo que necessitam de intervenção urgente. Isto requer a identificação das deficiências e a aplicação de técnicas de intervenção apropriadas. Uma das técnicas possíveis para trabalhos de consolidação estrutural das paredes de alvenaria de pedra é a injeção de argamassas fluidas denominadas correntemente por caldas. A escolha destas caldas é muito importante no que respeita, em particular, às suas propriedades químicas e físicas. Neste estudo, realizado no âmbito do Mestrado em Engenharia Química, foram utilizados dois tipos de caldas à base de cal, com a finalidade de comparar e avaliar a sua resistência química face à cristalização de sais solúveis. Uma das caldas é uma mistura pré-doseada comercialmente disponível, a Mape-Antique I da empresa Mapei (CA) e a segunda calda é uma mistura preparada em laboratório (LB), composta por metacaulino, cimento, cal hidratada, água e um superplastificante. Com o proposto de avaliar a ação dos sulfatos sobre estas caldas, submeteram-se uma série de provetes a ciclos molhagem-secagem usando duas temperaturas diferentes, 20 °C e 50 °C. Durante a experiência determinou-se a variação do peso e da resistência à compressão das caldas analisadas, assim como a concentração de ião sulfato e pH da solução onde foram mergulhadas as amostras. A calda comercial (CA) apresenta aparentemente uma resistência química aos sulfatos superior, no entanto a calda LB mostrou ter, em alguns parâmetros, resultados positivos.