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Published: 4 June 2021
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1

Terjeson, Robin Joyce. "The Chemistry of Sulfonyl Fluorides: SF5 and/or SO2F Containing Compounds as Precursors to Sulfonic Acids." PDXScholar, 1989. https://pdxscholar.library.pdx.edu/open_access_etds/1241.

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Sulfonyl fluoride systems and their derivatives, RS02F, where R represents hydrocarbon/fluorocarbon moieties continue to be of considerable interest. The incorporation of the sulfonyl fluoride group (S02F) into molecular systems can lead to compounds that are useful as ion-exchange resins, surface active agents, fuel cell electrolytes, and strong sulfonic acids/salts. Interest in preparing SF5 containing sulfonyl fluorides led to the synthesis of the ᵝ-sultone, SF5CHCF20S02, and its rearranged product. Hydrolysis of the sultone gave SF5CH2S02F which led to the sulfonic acid and salt, SF5CH2S03H•H20 and (SF5CH2S03)2Ca. Esters of the sultone were prepared by reaction of the sultone with fluorinated alcohols in the presence of NaF to give SF5CH(S02F)C(O)OR where R = CH2CF3 and CH(CF3)2. Polymeric SF5/S02F containing esters were prepared by reaction of allyl esters, RCX(S02F)C(O)OCH2CH=CH2, in ultraviolet light where R = CF3 or SF5 and X= H or F. Fluorinated silver carboxylate salts have been useful in preparing fluoroesters from alkyl iodides. Therefore, a new silver salt, FS02CF2C(0)0Ag was prepared and characterized; its reaction with (CH3)3SiI, HOCH2CH2I and alkyl bromides and iodides are reported. In addition, new SF5 containing fluoropolymers were synthesized via reaction of fluorinated olefins with SF5Br. Reactions of SF5 containing olefins with CF30Cl, C1F and Cl2 provide reagents that may be of potential use as precursors to sulfonyl fluoride containing systems. All new compounds were characterized by their respective infrared, nmr and mass spectra.
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2

Hamel, Nicolas Noel. "Monomeric and Polymeric Fluoroalkyl Sulfonyl Fluorides, Sulfonate Salts and Sulfonic Acids for Use as Electrolytes and Coatings." PDXScholar, 1995. https://pdxscholar.library.pdx.edu/open_access_etds/1265.

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Monomeric and polymeric fluoroalkyl sulfonyl fluorides, sulfonate salts and sulfonic acids have qualities desirable for use as electrolytes in alternative energy sources such as fuel cells and solid polymer electrolyte lithium batteries. Since the nature of the fluoroalkyl group affects the properties of these compounds, new monomeric and polymeric fluoroalkyl sulfonyl fluorides, sulfonate salts and sulfonic acids were prepared in this work. Simple compounds prepared in this work were: the fluoroalkyl sulfonyl fluorides, sulfonate salts and sulfonic acid CHF (OCF₂CF2SO₂ F)₂ CF₂(OCF₂CF₂SO₂F) ₂ CH₂(OCF₂CF₂SO3Na) ₂ CF₂(OCF₂CF₂SO3 ) ₂Ca , CF₂(OCF₂CF₂SO3H) ₂ prepared by means of electrochemical fluorination; FC (CF3 ) ₂OCH₂CH₂OCF₂CF₂SO₂F prepared using the adduct of hexafluoroacetone and silver fluoride; CH₃OCF₂CF₂SO₂F prepared as a substrate for free-radical substitution reactions of fluorinated species; and the pentafluorosulfur lithium sulfonate salts SFsCHFSO₃Li and SFsCF₂SO₃Li. Novel compounds containing both alcohol and fluoroalkyl sulfonyl functional groups were prepared: the chlorohydrin ClCH₂CH (OH) CH₂OCF₂CF₂SO₂F; the benzyl ethers HOCH₂CH (OCH₂C6Hs) CH₂OCF₂CF₂SO₂F and C6HsCH₂OCH₂CH (OH) CH₂OCF₂CF₂SO₂F as a product mixture; and the diol HOCH₂CH (OH) CH₂OCF₂CF₂SO₂F. The diol was found to be a useful synthon for the preparation of two polymeric fluoroalkyl sulfonyl fluorides: the polyester [C (O)CF₂CF₂CF₂ C (O) OCH₂CH (CH₂OCF₂) CF₂SO₂F] O]n by reaction with perfluoroglutaric anhydride and a polyurethane formed with 1,6-diisocyanohexane. Other polymeric compounds prepared were: the sulfonyl fluoride, sulfonate salt and sulfonic acid [OCH₂CH (CH₂OCF₂CF₂SO₂F)]n, [OCH₂CH (CH₂OCF₂CF₂SO₃Na)]n, and [OCH₂CH (CH₂OCF₂CF₂SO₃H)]n prepared by homopolymerization of the epoxide OCH₂CHCH₂OCF₂CF₂SO₂F; a cross-linked copolymer of the same epoxide; and the fluoroalkyl sulfonyl fluoride polyacrylat [-CH₂-CH-(CO₂CH₂CH₂CF₂CF₂OCF₂CF₂SO₂F)]n prepared from the acrylate ester H₂C=CHC (O) OCH₂CH₂CF₂SO₂F. ¹H, ¹⁹F and ¹³C nuclear magnetic resonance spectroscopy, infrared spectroscopy, mass spectrometry, melting point or boiling point, elemental analysis, contact angles, optical clarity, refractive index, and specific conductivity were among the techniques used to characterize the compounds.
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3

Rambocus, Subhas. "Reactive solvent extraction of dicarboxylic and carboxylic-sulfonic acids." Thesis, London South Bank University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.245144.

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4

Willenbring, Robert J. "Synthesis and characterization of some SF₅- containing sulfonic acids." PDXScholar, 1987. https://pdxscholar.library.pdx.edu/open_access_etds/3734.

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Pentafluorosulfur (VI) bromide (SF5Br) adds to olefins of the form CX2=CX2, where X= H or F, with the pentafluorosulfur group usually adding to the carbon with more hydrogens attached to it. This series of compounds was used in an attempt to prepare the corresponding sulfonic acid hydrates of the general formula SF5CX2CX2SO3H·nH2O, in order to have these compounds tested as possible fuel cell electrolytes. The reaction scheme involved reflux of the SF5Br adduct with an equimolar amount of sodium sulfite in 50% ethanol for two days, followed by acidification of the recovered solid material using HCl or H2SO4.
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5

Dong, Daxuan. "Polyphenylene Sulfonic Acids As Proton Exchange Membranes For Fuel Cells." Case Western Reserve University School of Graduate Studies / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=case1332355539.

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6

Kusoglu, Ahmet. "Mechanical characterization of perfluorosulfonic acid (PFSA) ionomer membranes." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 203 p, 2009. http://proquest.umi.com/pqdweb?did=1885675131&sid=3&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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7

Mohtasham, Javid. "Fluorinated [beta]-sultones as Precursors to Fluorinated Sulfonic Acids, and New Fluorosulfonyl Containing Monomers/Polymers." PDXScholar, 1989. https://pdxscholar.library.pdx.edu/open_access_etds/1250.

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Sulfur trioxide (SO₃) adds to fluoroolefins of the form RCF=CF₂, (where R = F, SF₅, CF₃, CF₃OCF₂, CF₂=CF(CF₂)₂, CF₃(CF₂)₃O, CF₃O(CF₂)₂OCF₂, or CH₂ClCHClCH₂), yielding the fluorinated [beta]-sultones, RCFCF₂OSO₂. In the case of CF₃(CF₂)₃OCF=CF₂, a reverse addition occurs, giving the sultone, CF₃(CF₂)₃CF₂2OCFCF₂SO₂O. The fluoro [beta]-sultones are capable of undergoing different reactions, such as rearrangement, hydrolysis, esterification, and polymerization. These reactions, will result in the formation of compounds containing the fluorosulfonyl grouping (SO₂F); it is this group that yields the corresponding sulfonic acid upon base/acid treatment. The addition of sodium bisulfite to CF₃CF= CF₂ and CF₃(CF₂)₄CF=CF₂ in the presence of (C₆H₅CO)₂O₂ and Na₂B₄O₇·10H₂O was also studied to produce the corresponding sulfonic acid hydrates of the general formula, R[subscript f]CFHCF₂SO₃H·nH₂O. These acids were prepared, and thus, tested as possible fuel cell electrolytes. Infrared, ¹H and ¹⁹F nuclear magnetic resonance and mass spectra, as well as elemental analyses, will be presented in order to support the proposed structures for the resulted compounds.
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8

Winter, Rolf Walter. "Chemistry of Pentafluorothio (SF5) Alkyl Derivatives." PDXScholar, 1990. https://pdxscholar.library.pdx.edu/open_access_etds/1281.

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Part I describes the preparation of a number of useful intermediates from the sultone F5SCHCF2OSO2 (1). These intermediates include the following: the ketene F5SC(SO2)=C=O (21), the unique sultone F4S=CCF2OSO2 (23), and various ionic intermediates of the form Y+ [F5SC(SO2F) COX]-. These intermediates play an important role in providing new pathways for preparing fluorosulfonic acid precursors. Fluorosulfonic acids are excellent candidates to improve the efficiency of environmentally safe fuel cells. It was possible to obtain new derivatives of 1 by various reactions of 21, 23 and the ionic intermediates, but it was not possible to introduce an alkyl substituent with either of the intermediates. Part II is concerned with the synthesis of SF5 containing epoxides as possible monomers. When polymerized, materials of high dielectric strength and high chemical resistance should be obtained. The reaction chemistry of one of the epoxides was investigated and it was found that all reactions studied were accompanied by the loss of the SF5 group. Thus, it was not possible to obtain any polymeric materials. Part III deals with the synthetic accessibility of SF$\sb5$ malonic esters and thence of SF$\sb5$ acrylic esters. These compounds should serve as building blocks in the synthesis of SF$\sb5$ containing pyrimidines. The CF3 analogue, 5-trifluoromethyl uracil, is used as an antiviral drug. In order to synthesize either SF5 malonic ester or 2-SF5 acrylic ester an SF5 group has to be introduced at a secondary carbon. A secondary SF$\sb5$ compound could be synthesized (F5SCH (COOC2H5) (CHBrOAc)) but could not be converted to the respective malonic ester F5SCH (COOC2H5) compound. Part IV describes the reactions and preparations of Parts I-III.
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9

Hicks, Jason Christopher. "Organic/inorganic hybrid amine and sulfonic acid tethered silica materials synthesis, characterization and application /." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/26583.

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Thesis (Ph.D)--Chemical Engineering, Georgia Institute of Technology, 2008.
Committee Chair: Jones, Christopher; Committee Member: Koros, William; Committee Member: Lyon, Andrew; Committee Member: Nair, Sankar; Committee Member: Weck, Marcus. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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10

Granados-Focil, Sergio. "A new class of polyelectrolytes, poly(phenylene sulfonic acids) and its copolymers as proton exchange membranes for PEMFC'S." online version, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=case1129082182.

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11

Granados-Focil, Sergio. "A new class of polyelectrolytes, poly(phenylene sulfonic acids) and its copolymers as proton exchange membranes for PEMFC’s." Case Western Reserve University School of Graduate Studies / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=case1129082182.

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12

Neuendorf, Annette J., and n/a. "High Pressure Synthesis of Conducting Polymers." Griffith University. School of Science, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20040218.112214.

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An experimental investigation of the high pressure synthesis of water soluble, self doping conducting polymers is presented. 2- And 3-aminobenzenesulfonic acid and the respective sodium sulfonates have been polymerised. Optimal polymerisation conditions have been determined with respect to yield, conductivity and molecular weight. Reaction parameters such as oxidant, pressure, catalysts, reaction time and temperature and the use of additives were investigated. The minimum pressure required for polymerisation was 7 kbar. An increase in pressure had a negligible effect on polymer characteristics. The polymers were generated in aqueous, non-acidic media, to ensure they were selfdoping when characterised. Conductivities of between 10-6 Scm-1 and 10-3 Scm-1 were measured. The sulfonate salts reacted faster than the sulfonic acids and for both a longer reaction time resulted in higher yields and conductivities. These polymers were completely water soluble, of high molecular weight and able to be cast as thin films. The arylamines 5- and 8-aminonaphthalene-2-sulfonic acid and their respective sodium sulfonates were polymerised at elevated pressure. The naphthalene sulfonate salts polymerised at atmospheric pressure, but displayed a higher molecular weight when reacted under pressure. Generally the naphthalene monomers reacted similarly to the benzene monomers, although there were some differences. Conductivity and yield decreased with increased reaction times and the use of 0.1M equivalents of ferrous sulfate had an negligible effect on the polymers. The polynaphthalenes were highly water soluble, self doping and had conductivities in the order 10-5 to 10-3 Scm-1. A measurement of the activation volume for the polymerisation of 2-methoxyaniline and sodium 8-aminonaphthalene-2-sulfonate was performed. These were determined to be -44 ± 3 cm3mol-1 and -62 ± 10 cm3mol-1 respectively. These large negative values are consistent with rate limiting monomer oxidation.
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13

Neuendorf, Annette J. "High Pressure Synthesis of Conducting Polymers." Thesis, Griffith University, 2004. http://hdl.handle.net/10072/366536.

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An experimental investigation of the high pressure synthesis of water soluble, self doping conducting polymers is presented. 2- And 3-aminobenzenesulfonic acid and the respective sodium sulfonates have been polymerised. Optimal polymerisation conditions have been determined with respect to yield, conductivity and molecular weight. Reaction parameters such as oxidant, pressure, catalysts, reaction time and temperature and the use of additives were investigated. The minimum pressure required for polymerisation was 7 kbar. An increase in pressure had a negligible effect on polymer characteristics. The polymers were generated in aqueous, non-acidic media, to ensure they were selfdoping when characterised. Conductivities of between 10-6 Scm-1 and 10-3 Scm-1 were measured. The sulfonate salts reacted faster than the sulfonic acids and for both a longer reaction time resulted in higher yields and conductivities. These polymers were completely water soluble, of high molecular weight and able to be cast as thin films. The arylamines 5- and 8-aminonaphthalene-2-sulfonic acid and their respective sodium sulfonates were polymerised at elevated pressure. The naphthalene sulfonate salts polymerised at atmospheric pressure, but displayed a higher molecular weight when reacted under pressure. Generally the naphthalene monomers reacted similarly to the benzene monomers, although there were some differences. Conductivity and yield decreased with increased reaction times and the use of 0.1M equivalents of ferrous sulfate had an negligible effect on the polymers. The polynaphthalenes were highly water soluble, self doping and had conductivities in the order 10-5 to 10-3 Scm-1. A measurement of the activation volume for the polymerisation of 2-methoxyaniline and sodium 8-aminonaphthalene-2-sulfonate was performed. These were determined to be -44 ± 3 cm3mol-1 and -62 ± 10 cm3mol-1 respectively. These large negative values are consistent with rate limiting monomer oxidation.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Science
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14

Maisonet, Mildred, Antonia M. Calafat, Michele Marcus, Jouni J. K. Jaakkola, and Hany Lashen. "Prenatal Exposure to Perfluoroalkyl Acids and Serum Testosterone Concentrations at 15 Years of Age in Female ALSPAC Study Participants." Digital Commons @ East Tennessee State University, 2015. https://dc.etsu.edu/etsu-works/1.

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Background: Exposure to perfluorooctane sulfonic acid (PFOS) or to perfluorooctanoic acid (PFOA) increases mouse and human peroxisome proliferator–activated receptor alpha (PPARα) subtype activity, which influences lipid metabolism. Because cholesterol is the substrate from which testosterone is synthesized, exposure to these substances has the potential to alter testosterone concentrations. Objectives: We explored associations of total testosterone and sex hormone–binding globulin (SHBG) concentrations at age 15 years with prenatal exposures to PFOS, PFOA, perfluorohexane sulfonic acid (PFHxS), and perfluoronanoic acid (PFNA) in females. Methods: Prenatal concentrations of the perfluoroalkyl acids (PFAAs) were measured in serum collected from pregnant mothers at enrollment (1991–1992) in the Avon Longitudinal Study of Parents and Children (ALSPAC). The median gestational age when the maternal blood sample was obtained was 16 weeks (interquartile range, 11–28 weeks). Total testosterone and SHBG concentrations were measured in serum obtained from their daughters at 15 years of age. Associations between prenatal PFAAs concentrations and reproductive outcomes were estimated using linear regression models (n = 72). Results: Adjusted total testosterone concentrations were on average 0.18-nmol/L (95% CI: 0.01, 0.35) higher in daughters with prenatal PFOS in the upper concentration tertile compared with daughters with prenatal PFOS in the lower tertile. Adjusted total testosterone concentrations were also higher in daughters with prenatal concentrations of PFOA (β = 0.24; 95% CI: 0.05, 0.43) and PFHxS (β = 0.18; 95% CI: 0.00, 0.35) in the upper tertile compared with daughters with concentrations in the lower tertile. We did not find evidence of associations between PFNA and total testosterone or between any of the PFAAs and SHBG. Conclusions: Our findings were based on a small study sample and should be interpreted with caution. However, they suggest that prenatal exposure to some PFAAs may alter testosterone concentrations in females.
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15

Svarovsky, Serge A. "Structure, stability and reactivity of small organic sulfinic and sulfonic acids toxicological implications ; Role of charge transfer complexes in oxidation cleavage of benzpinacols by iron (III) trispenanthroline /." Morgantown, W. Va. : [West Virginia University Libraries], 2000. http://etd.wvu.edu/templates/showETD.cfm?recnum=1231.

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16

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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17

Telfah, Ahmad D. S. "Transport of protonic charge carriers in methyl-sulfonic-acid/water mixtures a model for lowly hydrated sulfonic acid based ionomers /." [S.l. : s.n.], 2008. http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-36945.

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18

Davison, Andrea Dianne. "Synthesised sulfonic solid acid catalysts for liquid phase reactions." Thesis, University of Huddersfield, 2008. http://eprints.hud.ac.uk/id/eprint/5014/.

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The move to use heterogeneous solid acid catalysts as new, cleaner, renewable catalysts for liquid phase reactions is at the forefront of scientific research, with the focus on the ability to tailor and improve the physical and chemical properties of the catalysts in order to tailor their acidity to catalytic activity for specific liquid phase reactions. The aim of this project was to determine the role of the support in imparting acidity and catalytic activity in liquid phase reactions to three different types of supported solid acid catalyst; polystyrene, silica and a fluorinated hydrocarbon polymer. For the sulfonic acids supported on silica, two main synthesis routes (grafted and co-condensed) with the use of two alternative tethers (propyl, phenyl and also an additional non acidic tether) were compared. Of the synthesised materials, structural properties were characterised and compared using several techniques. Nitrogen adsorption was used in order to ascertain the pore size and distribution, X-ray diffraction to determine the long range order, elemental analysis to determine the relative sulfur content and X-ray phototelectron spectroscopy to analyse the environment of the sulfur in order to establish successful acidification. Surface acidities of all three supported sulfonic acids were better characterised and compared using ammonia adsorption calorimetry. The extent of the adsorption and molar enthalpies of ammonia adsorption (ΔHadsn) were interpreted in terms of abundance, accessibility and strength of surface acid sites. Catalytic activities were measured and compared using the isomerization of α-pinene liquid phase reaction. In brief, the main findings of this project indicate that the commercially available fluorinated polymer Nafion® resin demonstrated the highest acid strength and much higher specific catalytic activities compared to the other supported sulfonic acids. The acid strengths on polymeric and silica supports were similar, with poor catalytic activities. The routes used in order to synthesise, characterise and acidify the supported sulfonic acids were successful.
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19

Onomura, Masahisa. "Effect of argatroban on trinitrobenzene sulfonic acid-induced colitis." Kyoto University, 2001. http://hdl.handle.net/2433/150182.

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20

Slapelis, Linda. "Plasma modification of poly(ester sulfonic) acid anionomeric membranes /." Online version of thesis, 1994. http://hdl.handle.net/1850/11445.

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21

Telfah, Ahmad, Günter Majer, Michael Schuster, Klaus-Dieter Kreuer, and Joachim Maier. "PFG NMR studies of diffusion in sulfonic acid based systems." Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-197101.

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22

Telfah, Ahmad, Günter Majer, Michael Schuster, Klaus-Dieter Kreuer, and Joachim Maier. "PFG NMR studies of diffusion in sulfonic acid based systems." Diffusion fundamentals 2 (2005) 134, S. 1-2, 2005. https://ul.qucosa.de/id/qucosa%3A14479.

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23

Ennari, Jaana. "Atomistic molecular modelling of PEO sulfonic acid anion based polymer electrolytes." Helsinki : University of Helsinki, 2000. http://ethesis.helsinki.fi/julkaisut/mat/kemia/vk/ennari/.

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24

Li, Lei [Verfasser]. "Supramolecular complexes of wedge-shaped sulfonic acid molecules with polybases / Lei Li." Aachen : Hochschulbibliothek der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2012. http://d-nb.info/1029723281/34.

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25

陸皓開 and Ho-hoi Luk. "Effects of zinc on 2,4-dinitrobenzene sulfonic acid-induced ulcerativecolitis in rats." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B3196977X.

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26

Wark, Michael, Monir Sharifi, Roland Marschall, Martin Wilkening, Pia Tölle, Christof Köhler, Thomas Frauenheim, and Dirk Wallacher. "Proton conductivity of aluminium or sulfonic acid functionalized ordered mesoporous silica materials." Universitätsbibliothek Leipzig, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-186778.

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27

Wark, Michael, Monir Sharifi, Roland Marschall, Martin Wilkening, Pia Tölle, Christof Köhler, Thomas Frauenheim, and Dirk Wallacher. "Proton conductivity of aluminium or sulfonic acid functionalized ordered mesoporous silica materials." Diffusion fundamentals 12 (2010) 43, 2010. https://ul.qucosa.de/id/qucosa%3A13884.

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28

Neves, Regina Maria de Almeida. "Reações de α-sulfonil carbânions: alquilação e sulfenilação de alguns α-sulfonil tioésteres. Descarboxilação alquilativa dos ácidos α-fenilsulfonil-α-fenilpropanóicos racêmico e opticamente ativo." Universidade de São Paulo, 2000. http://www.teses.usp.br/teses/disponiveis/46/46135/tde-28052015-160006/.

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A presente tese trata de α-sulfonil carbânions, trazendo uma contribuição para a compreensão da sua estabilidade conformacional e reatividade frente a reagentes eletrofílicos. As reações investigadas foram as alquilações e sulfenilações de α-sulfonil tioésteres e as descarboxilações alquilativas dos ácidos α-fenilsulfonil-α-fenilpropanóicos racêmico e opticamente ativo. A apresentação e discussão dos resultados das reações de alquilação e sulfenilação é precedida por uma revisão bibliográfica que apresenta os trabalhos mais relevantes da literatura sobre as reações de α-sulfonil carbânions com diversos eletrófilos, envolvendo reações tais como: halogenação, alquilação, acilação, condensação e sulfenilação. Os estudos das reações de alquilação, por nós efetuados com dois diferentes α-sulfonil tioésteres, empregando o método em fase homogênea, indicaram que, no caso dos haletos de metila, etila e alila, foram obtidas misturas dos produtos mono- e di- alquilados, enquanto que no caso do brometo de benzila houve formação exclusiva de produtos monoalquilados (ver arquivo). Entretanto, a alquilação pelo emprego do método de catálise de transferência de fase (CTF), efetuada com o α-fenilsulfonil tioacetato de metila, conduziu exclusivamente aos produtos monoalquilados correspondentes, independentemente do reagente alquilante empregado (ver arquivo). Estes resultados mostraram a superioridade do método em transferência de fase sobre o em fase homogênea. Os estudos das reações de sulfenilação, efetuados com o α-fenilsulfonil tioacetato de metila e os seus derivados α-alquilsubstituídos, empregando o método CTF, conduziram exclusivamente aos produtos monossulfenilados (ver arquivo). Neste caso, o método em transferência de fase também se mostrou superior ao em fase homogênea, sendo os produtos monossulfenilados obtidos em maior rendimento. É sugerido um mecanismo para as reações de alquilação e sulfenilação de α-sulfonil tioésteres em CTF, empregando sistema sólido / líquido, o qual explica a ausência, nestas condições reacionais, dos produtos dialquilado e dissulfenilado. A apresentação e discussão dos resultados das reações de descarboxilação alquilativas dos ácidos α-fenilsulfonil-α-fenilpropanóicos racêmico e opticamente ativo é precedida por uma introdução que apresenta os estudos mais relevantes da literatura sobre as reações de descarboxilação de ácidos α-sulfonil carboxílicos na presença de eletrófilos, tais como hidrogênio, halogênio, carbono e enxofre. São de especial interesse os estudos envolvendo o curso estereoquímico da reação de descarboxilação protonativa de ácidos α-sulfonil carboxílicos opticamente ativos em meio alcalino, demonstrando a grande estabilidade do α-sulfonil carbânion, que retém a sua configuração original, sendo esta mantida mesmo após a protonação. Estas investigações se relacionam com os nossos estudos de descarboxilação alquilativa dos ácidos α-fenilsulfonil-α-fenilpropanóicos racêmico e opticamente ativo, efetuados em continuação aos estudos anteriores de descarboxilações alquilativas dos ácidos α-fenilsulfonil-α-fenil carboxílicos realizados no nosso laboratório. Os nossos resultados mostraram que é possível obter a sulfona tetrassubstituída pela reação do ácido α-fenilsulfonil-α-fenilpropanóico com iodeto de etila na presença de NaH / DMSO, desde que se expulse o CO2 formado na reação (ver arquivo). É apresentada a síntese do ácido α-fenilsulfonil-α-fenilpropanóico opticamente ativo, o qual foi obtido por vários passos reacionais, através da resolução do ácido α-fenilsulfenil-α-fenilpropanóico e a sua posterior oxidação. A configuração de ambos os compostos foi determinada pela análise de raios X, mostrando ser o isômero S. As sínteses destes ácidos foram efetuadas por dois métodos distintos, constituídos de 3 e 5 passos reacionais. Entretanto, não foi possível obter a sulfona tetrassubstituída opticamente ativa pela reação do ácido α-fenilsulfonil-α-fenilpropanóico opticamente ativo com iodeto de etila nas mesmas condições empregadas no caso do composto racêmico correspondente. Foi obtido um esclarecimento do processo da descarboxilação de ácidos α-sulfonil carboxílicos a partir de cálculos semi-empíricos que mostraram a existência de duas etapas intermediárias na descarboxilação dos respectivos carboxilatos, ou seja, uma em que o CO2 se liga ao carbânion (I) e outra, de mais baixa energia, em que ele se liga ao oxigênio sulfonílico (II) (ver arquivo). Foram fornecidas provas, através de experiências comparativas de alquilação e protonação, que para que o α-sulfonil carbânion mantenha a sua configuração, é necessário que o eletrófilo reaja com o carbânion antes da expulsão total de CO2, isto é, na fase em que ele se encontra ligado ao oxigênio sulfonílico (II). Este é o caso da descarboxilação protonativa, que mostrou ocorrer com retenção da configuração na experiência por nós realizada. A racemização que ocorre no caso da descarboxilação alquilativa foi atribuída à pequena janela de reação, que impede a aproximação do reagente alquilante. Foi por nós sugerido que a ligação do CO2 ao oxigênio sulfonílico seria responsável pela barreira rotacional que mantém a assimetria do α-sulfonil carbânion, tornando-o conformacionalmente estável. No decorrer do presente estudo foram sintetizados 11 compostos ainda não descritos na literatura, entre eles: três α-bromo tioésteres, cinco α-sulfonil tioésteres, quatro α-sulfonil tioésteres α-sulfenilados e uma sulfona tetrassubstituída.
This thesis gives a contribution to the chemistry of α-sulfonyl carbanions, such as the comprehension of its conformational stability and reactivity towards electrophilic reagents. The investigated reactions were alkylation and sulfenylation of α-sulfonyl thioesters and the decarboxylative alkylation of racemic and optically active α-phenylsulfonyl-α-phenylpropanoic acids. The presentation of the results and the discussion of the alkylation and sulfenylation reactions are preceded by a bibliographic revision describing the most important reports in the literature concerning the reactions of α-sulfonyl carbanions with different electrophiles, such as: protonation, halogenation, alkylation, acylation, condensation and sulfenylation. Our studies of the alkylation reaction, carried out with two different α-sulfonyl thioesters, employing homogeneous media, indicated that in the case of methyl, ethyl and allyl halides, mixtures of mono- and dialkylated products were obtained. However, in the case of benzyl bromide, the corresponding monoalkylated compound was obtained as the only reaction product (see file). On the other hand, the alkylation of methyl α-phenylsulfonyl thioacetate by PTC method afforded, exclusively, the corresponding monoalkylated products. These results show the superiority of the PTC method over the homogeneous one (see file). The sulfenylation reactions carried out with methyl α-phenylsulfonyl thioacetate and their α-alkylsubstituted derivatives employing PTC conditions, afforded only monosulfenylated α-sulfonyl thioesters as the only reaction products. Also in this case, the PTC method showed to be superior to give the monosulfenylated products in higher yields (see file). A mechanism for the alkylation and sulfenylation reactions in solid / liquid PTC system, which explains the absence of the dialkylated and disulfenylated products is suggested. The presentation and discussion of the results for the alkylative decarboxylation reactions of racemic and optically active α-phenylsulfonyl-α-phenylpropanoic acids is preceded by a bibliographic introduction reporting the most important works in the literature concerning the decarboxylation of α-sulfonyl carboxylic acids in the presence of electrophiles such as hydrogen, halogens and sulfur. Specially important are the studies on the stereochemical course of the base-catalyzed protonative decarboxylation of optically active α-sulfonyl carboxylic acids, showing the high stability of the a-sulfonyl cabanion, which retains its original configuration even after protonation. There is a link between these investigations and our studies of the alkylative decarboxylation of racemic and optically active α-phenylsulfonyl-α-phenylpropanoic acids, which are undertook in continuation to our investigations on the alkylative decarboxylation of α-phenylsulfonyl-α- phenyl carboxylic acids. Our results showed that it is possible to obtain the tetrasubstituted sulfone from the reaction of α-phenylsulfonyl-α-phenylpropanoic acid with ethyl iodide, in the presence of NaH / DMSO as base, provided that the CO2, which is formed during the reaction, is expelled (see file). The synthesis of the optically active α-phenylsulfonyl-α-phenylpropanoic acid containing several reaction steps is presented, through the resolution of the α-phenylsulfenyl-α-phenylpropanoic acid, followed by its oxidation. The configurations of both acids were determined through X-rays analyses, and showed to be S. However, it was not possible to obtain the optically active tetrasubstituted sulfone from the reaction of optically active α-phenylsulfonyl-α-phenylpropanoic acid with ethyl iodide in the experimental conditions employed for the corresponding racemic acid. The insight for the decarboxylation process of the α-sulfonyl carboxylic acids was obtained from semi-empiric calculations that showed the existence of two intermediate steps in the decarboxylation of the corresponding carboxylates, one of which with CO2 bonded to the carbanion and another one, of lower energy, in which the CO2 is linked to the sulfonyl oxygen (see file). Proofs were provided, through the comparative experiments of alkylation and protonation for the optically active α-sulfonyl acid, that for retention of configuration of the α-sulfonyl carbanion it is necessary that the reaction of the carbanion with the electrophile takes place before the total expulsion of CO2, i.e., when it is linked to SO2. It was suggested that the CO2-OSO linkage could be responsible for the rotational barrier, which maintains the symmetry of the a-sulfonyl carbanion, which becomes conformationaly stable. Finally, eleven new compounds were prepared in the course of the present study such as: three α-bromo thioesters, five α-sulfonyl thioesters, four α-sulfenylated α-sulfonyl thioesters and one α-tetrasubstituted sulfone.
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Gómez, Pulido José Enrique. "Stereoselective Synthesis of Sulfones and Amino Acids from Functionalized Heterocycles." Doctoral thesis, Universitat Rovira i Virgili, 2019. http://hdl.handle.net/10803/668267.

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L'objectiu principal d'aquesta tesi és el desenvolupament de nous mètodes catalítics estereoespecífic i enantioselectius, aprofitant la reactivitat dels carbonats cíclics (COCs) funcionalitzats i altres heterocicles relacionats (lactones), usant-los com a precursors en la síntesi catalítica de molècules orgàniques més complexes, (específicament emprant Pd i Cu com metalls de transició). Tres projectes de recerca conformen aquesta tesi. El primer projecte mostra una nova metodologia enfocada a la síntesi estereoselectiva de tioèters al·lílics amb configuració (Z), i les seves respectives sulfones. Aquest protocol està basat en la descarboxilació catalitzada per pal·ladi de COC-vinílics en presència de tiols. Aquesta reacció ocorre amb bons rendiments i alta selectivitat. Tot i que existeixen metodologies conegudes per a la síntesi de tioèters / sulfones al·líliques, encara no hi ha una metodologia general per a la preparació de tioèters al·lílics tri- o tetrasubstituïts. Per tant, la nostra metodologia ofereix un potencial sintètic complementari. El segon projecte descriu la primera síntesi asimètrica de sulfones propargíliques terciàries. Aquests compostos presenten un gran interès tant en síntesi orgànica com en química medicinal. En aquest cas els COCs substituïts amb un alquí, recentment descoberts, ens van inspirar per desenvolupar la síntesi d'aquests compostos mitjançant una substitució propargílica catalitzada per coure, usant sals de sulfinat com nucleòfils. A més, aquesta metodologia obre un nou camí cap a la preparació de compostos de sofre amb centres tetrasubstituïts, amb una alta enantioselectivitat i diversitat sintètica. L'aplicabilitat d'aquesta metodologia es va demostrar mitjançant la funcionalització selectiva de les sulfones quirals obtingudes. Finalment, l'últim projecte d'aquesta tesi mostra el descobriment d'una nova reacció propargílica catalitzada per coure que permet la síntesi quiral de gamma-aminoàcids que contenen centres quaternaris. Aquest protocol es basa en l'obertura enantioselectiva de lactones substituïdes amb un grup alquí, en presència d'amines. Cal destacar que aquest tipus d'aminoàcids són molt interessants tant des del punt de vista biològic com sintètic, i ens han permès accedir a altres compostos també interessants coneguts com gamma-lactames.
El objetivo principal de esta tesis es el desarrollo de nuevos métodos catalíticos estéreo- y enantioselectivos, aprovechando la reactividad de los carbonatos cíclicos (COCs) funcionalizados y otros heterociclos relacionados (lactonas), usándolos como precursores en la síntesis catalítica de moléculas orgánicas más complejas, (específicamente empleando Pd y Cu como metales de transición). Tres proyectos de investigación conforman esta tesis. El primer proyecto muestra una nueva metodología enfocada en la síntesis estereoselectiva (Z) de tioéteres alílicos con configuración, y sus respectivas sulfonas. Este protocolo está basado en la descarboxilación catalizada por paladio de COC-vinílicos en presencia de tioles. Esta reacción ocurre con buenos rendimientos y alta selectividad. A pesar de que existen metodologías conocidas para la síntesis de tioéteres/sulfonas alílicas, todavía no existe una metodología general para la preparación de tioéteres alílicos tri- o tetrasustituidos. Por tanto, nuestra metodología ofrece un potencial sintético complementario. El segundo proyecto describe la primera síntesis asimétrica de sulfonas propargílicas terciarias. Estos compuestos presentan un gran interés tanto en síntesis orgánica como en química medicinal. En este caso los COCs sustituidos con un alquino, recientemente descubiertos, nos inspiraron para desarrollar la síntesis de estos compuestos mediante una sustitución propargílica catalizada por cobre, usando sales de sulfinato como nucleófilos. Además, esta metodología abre un nuevo camino hacia la preparación de compuestos de azufre con centros tetrasustituidos, con una alta enantioselectividad y diversidad sintética. La aplicabilidad de esta metodología se demostró mediante la funcionalización selectiva de las sulfonas quirales obtenidas. Finalmente, el último proyecto de esta tesis muestra el descubrimiento de una nueva reacción propargílica catalizada por cobre que permite la síntesis quiral de gamma-aminoacidos que contienen centros cuaternarios. Este protocolo se basa en la apertura enantioselectiva de lactonas sustituidas con un grupo alquino, en presencia de aminas. Cabe destacar que este tipo de aminoácidos son muy interesantes tanto desde el punto de vista biológico como sintético.
The main goal of this thesis is the development of new stereo- and enantio-selective catalytic methodologies taking advantage of the intrinsic reactivity of functionalized cyclic carbonates and related heterocycles (e.g., nonstrained lactones) and use them as starting materials for the synthesis of more complex chiral organic targets, by means of transition-metal (TM) catalysis (specifically Pd and Cu).Three main research projects are collected in this thesis. In the first project, a new methodology aiming at the stereoselective synthesis of highly functionalized (Z)-configured allylic thioethers and their corresponding sulfones has been developed. This protocol based on a Pd-catalyzed thiolation of vinyl cyclic carbonate substrates features good yields and high (Z)-selectivity. Although effective methodologies for the synthesis of allylic thioether/sulfones are well stablished, a general catalytic methodology for the stereoselective synthesis of (Z)-configured tri- and tetra-substituted allylic thioethers/sulfones remained previously elusive. Our newly developed procedure therefore offers complementary synthetic potential. The second project, describes the first asymmetric synthesis of tertiary propargylic sulfones. These building blocks are of significant importance in organic synthesis and medicinal chemistry. The recently introduced alkyne-functionalized cyclic organic carbonates inspired us to pursue a Cu-catalyzed asymmetric propargylic sulfonylation reaction of these precursors by using versatile sulfinate salts. This practical method provided a new approach targeting the construction of sulfur-containing, tetrasubstituted carbon stereocenters featuring high enantioselectivity and wide functional group diversity. The applicability of the transformation was demonstrated by various functionalization reactions of the tertiary sulfone building blocks. Finally, the last project shows the discovery of a new protocol that enables the efficient assembly of biologically relevant gamma-amino acids bearing quaternary stereocenters. Notably, in this project we took advantage of the catalytic formation of copper-allenylidene intermediates that can be intercepted by a series of amine nucleophiles in an enantioselective fashion allowing the ring opening aminolysis of minimally strained, alkyne-substituted lactones.
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30

Luk, Ho-hoi. "Effects of zinc on 2,4-dinitrobenzene sulfonic acid-induced ulcerative colitis in rats." Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B22190077.

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31

Wu, Zheng-hui. "Fundamental study on extracting lead from cerussite concentrate in methane sulfonic acid based solution." Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/43660.

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Cerussite (PbCO₃) concentrates may be recovered from oxidized lead ores. These concentrates suffer from the intrinsic fuel shortage via traditional smelting route and may lead to widespread contamination in shipment. Therefore, a hydro-electrometallurgical process to treat cerussite concentrate by methane sulfonic acid (MSA) is proposed to solve the above problems. The leaching of cerussite concentrate by MSA was first studied. The parameters of stirring speed, temperature, acid concentration, particle sizes and solid concentration were considered. It was found that stirring speed, temperature, particle size and proton concentration had a significant influence on the kinetics while solid concentration showed no effect on the final lead extraction under the experimental conditions. The leaching results indicated that MSA is favourable to treat cerussite concentrate and the lead extraction could achieve the theoretical maximum in just 10 min at ambient conditions. The lead content in solution obtained at high solid concentration was sufficiently high, and easily met the concentration requirements for the subsequent electrolysis process. After leaching, the residue was subjected to a desulfurization treatment to recover the remaining lead in residue. Using desulfurization agent Na₂CO₃, the remaining lead, mainly in anglesite, was transformed to PbCO₃ that was followed by a re-leaching treatment with MSA. An overall lead recovery of 98% was finally obtained. In the electrowinning process from MSA based electrolyte, the individual and synergistic effects of two ligninsulfonate salts and two glycol-type agents on lead deposit quality were first investigated. Compared to the other three additives, the individual use of calcium ligninsulfonate most benefited the morphology of lead deposit. The operating parameters in the lead electrowinning process (i.e. temperature, current density, concentrations of lead ion and protons) had a widely acceptable range. The cathodic current efficiency and specific energy consumption in most tests were around 99% and 0.53Wh/kg, respectively. The SEM micrographs showed that the lead deposits obtained under the optimal conditions were compact and even. These results for leaching and electrolysis made the MSA system competitive to the comparable fluoborate and fluosilicate systems. Finally a simplified flowsheet to extract lead from cerussite concentrate in MSA based solution was proposed.
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32

Zhang, Yuchen. "Ammonia Adsorption by A Task-Specific Sulfonic Acid Ionic Liquid Supported on SBA-15." Thesis, University of South Alabama, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10604028.

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Composites of SBA-15 and a task specific sulfonic acid ionic liquid, 1-methyl-3-(propyl sulfonic acid) imidazolium triflate, [mimC3SO 3H][TfO], were produced. The ionic liquid was impregnated into SBA-15 silica via the incipient wetness method and the resulting composites were used to capture ammonia. This work examines how exposing the sorbents to water vapor impacts the ammonia adsorption capacity. The work also details the impact of solvent washes on the amount of ionic liquid impregnated in the pores of the SBA-15 silica. The results indicate that composite samples with low loading of the ionic liquid adsorb more ammonia than the parent SBA-15. Also, the data show that after exposure to water vapor, that regeneration at 200 °C under vacuum overnight is not sufficient to remove residual water contained in the composite. The following ammonia adsorption not only contains acid-base reaction, but also the combination reaction with formation of hydronium, [H 3O+]. Besides, the water has interaction with anions of the ionic liquid by hydrogen bonding and take the vacancy of the IL, which influences the physical absorption of ammonia. All these effects result in the residual water in the composite reducing the amount of ammonia that is adsorbed.

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Centrone, Charla Anne. "Synthesis of C-phosphonic acid, C-phosphinic acid, and C-sulfone analogs of decaprenolphosphoarabinose inhibitors of mycobacterial arabinosyltransferases /." Connect to this title online, 2003. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1054062979.

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Thesis (Ph. D.)--Ohio State University, 2003.
Document formatted into pages; contains xvi, 371 p.; also contains graphics. Includes bibliographical references. Abstract available online via OhioLINK's ETD Center; full text release delayed at author's request until 2005 May 5.
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34

Schory, David Henry. "Quantum Chemical Investigations of Nucleophilic Aromatic Substitution Reactions and Acid Dissociations of Aliphatic Carboxylic Acids." Wright State University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=wright1253480264.

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35

Rackemann, Darryn W. "Production of levulinic acid and other chemicals from sugarcane fibre." Thesis, Queensland University of Technology, 2014. https://eprints.qut.edu.au/72741/1/Darryn_Rackemann_Thesis.pdf.

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Lignocellulosics represent a renewable resource for producing fuels and chemicals as an alternative to fossil resources. This study utilised an organic acid catalyst and a co-solvent to develop an environmentally friendly processing technology for the production of levulinic acid and furfural from a waste material, sugarcane fibre.
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36

Svensson, David. "Synthesis and characterisation of polyelectrolytes based on polymers of diallyldimethyl ammonium chloride and poly(styrene-co-butadiene)." Thesis, Linköpings universitet, Institutionen för fysik, kemi och biologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-82344.

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In printed electronics there are many polyelectrolytes to choose from. While polyelectrolytes such as polystyrene sulfonic acid can fulfill many ofthe desired functionalities of a semiconductor, there is a need for other polyelectrolytes with other functionalities, such as functionality at low airhumidity and better cross-linking possibilities, while still functioning as a good semiconductor.Within this thesis, there is a description of general polyelectrolytes, as well as various usages.The synthesis and characterization of new polyelectrolytes that have been developed, based upon diallyldimethyl ammonium chloride (DADMAC)and a derivative of polystyrene sulfonic acid (PSSH) is described.The study and experimental testing of the polymers as polyelectrolytes under different conditions is described.
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37

Gamble, Mark Philip. "Novel and synthetic applications of #alpha#-amino acid derived sulfones." Thesis, University of York, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.362065.

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38

馮漢生 and Hon-sang Fung. "Effects of heparin on 2,4-dinitrobenzene sulfonic acid-induced ulcerative colitis and ethanol-induced gastritis in rats." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31969719.

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39

Abuzaydeh, Firas A. "Age-related gastrointestinal changes in trinitrobenzene sulfonic acid (TNBS)-induced rat model of colitis : a morphological assessment." Virtual Press, 2003. http://liblink.bsu.edu/uhtbin/catkey/1266022.

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40

Fung, Hon-sang. "Effects of heparin on 2,4-dinitrobenzene sulfonic acid-induced ulcerative colitis and ethanol-induced gastritis in rats." Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B22264565.

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41

Neskovic, Anika. "Exposure of Caco-2 cells to PFOS and PFOA." Thesis, Uppsala University, Department of Medical Biochemistry and Microbiology, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8048.

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The toxicity of perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) was measured. When Caco-2 cells from human adenocarcinoma are cultivated on a filter a monolayer is formed with properties similar to human duodenum epithelium. The Caco-2 cells grown on filter were exposed to the environmental contaminants PFOS and PFOA. The effects on the Caco-2 epithelium were examined by four different methods: trans-epithelial resistance (TEER), leakage of the intracellular protein lactate dehydrogenase (LDH), 14C-mannitol passage through the epithelium and protein content of the epithelium. TEER and C-mannitol passage show the Caco-2 cellmonolayer integrity, LDH leakage gives information of cytotoxicity and protein content of the epithelium shows cell adhension to the filter.

In the first study TEER decreased at the highest concentrations of PFOS and PFOA (1Mm). The 14C-mannitol passage increased at the highest PFOS concentration. No cytotoxicity was shown and protein-loss was not observed. The second study with PFOS doses of 0, 1, 10, 100 and 500µM and 1 and 10mM showed that the effect of PFOS on TEER was dose-dependent. The 14C-mannitol passage was very high at the highest PFOS-concentration (10mM) and a dose-response was indicated. No cytotoxicity was demonstrated and protein-quantity was not affected. In the third study it was demonstrated that the toxicity of PFOS did not depend on the different concentrations of the oil-emulsion used to dissolve PFOS and PFOA.

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Ndangili, Peter Munyao. "Amperometric biosensor systems prepared on poly (aniline-ferrocenium hexafluorophosphate) composites doped with poly(vinyl sulfonic acid sodium salt)." Thesis, University of the Western Cape, 2008. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_6605_1263418223.

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The main hypothesis in this study is the development of a nanocomposite mediated amperometric biosensor for detection of hydrogen peroxide. The aim is to combine the electrochemical properties of both polyaniline and ferrocenium hexafluorophosphate into highly conductive nano composites capable of exhibiting electrochemistry in non acidic media
shuttling electrons between HRP and GCE for biosensor applications.

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43

Ji, Yuefei. "Photochemical and photocatalytic degradation of pharmaceutical and personal care products (PPCPS) in aqueous solution : a case study of atenolol and 2-phenylbenzimidazole-5-sulfonic acid." Phd thesis, Université Claude Bernard - Lyon I, 2014. http://tel.archives-ouvertes.fr/tel-01058226.

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In this thesis, the photochemical and photocatalytic degradation of atenolol (ATL) and 2-phenylbenzimidazole-5-sulfonic acid (PBSA) have been investigated in aqueous solutions. Our results show that direct photolysis of ATL is weak and the indirect photolysis, e.g., induced by photosensitizers such as nitrate, may contributed to its major loss process in natural sunlit waters. In the case of PBSA, direct photolysis is found to be important while the indirect photolysis may play a less important role in its elimination in natural surface waters. The photolytic reactions (either direct or indirect) generally obey pseudo-first-order kinetics and can be influence by the solution pH, the co-existence of other water constituents such as dissolved organic matter (DOM) and bicarbonate ion (HCO3-). The photolytic degradation lead to a variety of intermediates and products. However, the reduction in TOC of the photolysis is usually found to be insignificant compared to the disappearance of the mother compound. Nevertheless, the observed decrease in toxicity toward fresh water species D. magna in nitrate-induced photodegradation of ATL implies indirect photolysis of ATL is possibly an important way to reduce the toxicity to ecosystem. It should be noted that direct and indirect photodegradation may process through different pathways and mechanism as observed in the photolysis of PBSA in this work. Photocatalytic oxidation of ATL and PBSA were carried out in illuminated aqueous TiO2 suspensions. Photocatalytic reactions normally follow pseudo-first-order kinetics. The kinetics are strongly affected by the photocatalyst type, the photocatalyst dosage, the solution pH value and the substrate concentration. Hydroxyl radical (HO*) was determined to be the major reactive specie responsible for the remarkable degradation of mother compounds. The degradation efficiency is largely influenced by the water matrices as well as the formation and transformation of intermediates. It should be noted that Degussa P25 showed the highest photocatalytic activity for oxidizing ATL and PBSA compared to pure anatase or rutile catalyst such as Hombikat UV 100, Millennium PC 500 and Aldrich rutile, which is in line with previous reports. The photocatalytic degradation of mother compounds results in the formation of various intermediates (e.g., formic, oxalic, malonic acid) and inorganic ions (e.g., NH4+, NO3-, SO42-). TOC decreases much more slowly as compared to the disappearance of the mother compounds, however, complete mineralization could be obtained with longer irradiation time
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Kim, ChulOong. "ENGINEERED INTERACTION BETWEEN PERFLUORINATED SULFONIC-ACID IONOMER (NAFION®) AND ELASTIN-LIKE PEPTIDES THROUGH PEPTIDE LENGTH AND GUEST RESIDUE." Case Western Reserve University School of Graduate Studies / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=case1564752880367712.

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45

Karaki, Mariam. "Matériaux à porosité contrôlée sulfonés : Synthèse, Caractérisation, Etude des propriétés catalytiques." Phd thesis, Université de Haute Alsace - Mulhouse, 2013. http://tel.archives-ouvertes.fr/tel-01064374.

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La catalyse solide acide a été pendant longtemps l'objet d'activité de recherche intense, en particulier pour l'industrie pétrochimique. Aujourd'hui, les catalyseurs solides acides sont de plus en plus étudiés dans d'autres domaines et en particulier dans celles liées à la "chimie verte" et à la valorisation des bioressources, telles que la synthèse de biodiesel et la transformation des polysaccharides. L'objectif de la thèse est d'étudier le potentiel des matériaux poreux sulfonés ayant une porosité contrôlée dans des réactions catalysées par un acide en condition eau surchauffé telle que l'hydrolyse de la cellobiose. Dans une première partie, nous décrivons la préparation et la caractérisation des organosilicates mésoporeux périodiques sulfonés de type SBA-15, SBA-1 et KIT-6 par co-condensation de 1,4-bis (triéthoxysilyl) benzène (BTEB). Les matériaux ont été acidifiés suivant des voies différentes à l'aide de 3-mercaptopropyltriméthoxysilane (MPTMS)/H2O2 ou d'acide chlorosulfonique (ClSO3H). Leur propriété acide a été étudiée par adsorption d'NH3 suivie par calorimétrie et par la réaction de déshydratation d'isopropanol (IPA) comme réaction modèle en phase gazeuse. Contrairement à notre attente, l'adsorption d'NH3 suivie par calorimétrie a mis en évidence l'hétérogénéité de la force des sites suggérant la présence de sites distincts de la sulfonation. Les solides sulfonés avec l'acide chlorosulfonique ont une activité équivalente à celle de la résine sulfonée, Amberlyst 15, mais ils sont moins stables en raison de la libération des espèces de soufre. Les catalyseurs préparés en utilisant un groupement mercapto-propyle suivie d'une oxydation sont moins acides et ils ont donné des niveaux d'activité plus basse dans la réaction de déshydratation d'IPA. Pour l'hydrolyse de la cellobiose, de bonnes performances ont été obtenues à 150°C, mais, ces matériaux se sont montrés instables dans des conditions hydrothermales avec une lixiviation totale de soufre réalisant alors la réaction en phase homogène. Un lavage dans l'eau surchauffée des matériaux contenant des groupements propyles-SO3H conduit à une diminution de leur efficacité dans l'hydrolyse de la cellobiose, mais un gain de stabilité a été obtenu, permettant le recyclage de ces matériaux. Dans une deuxième partie, des répliques carbonées sulfonées par l'acide chlorosulfonique ou l'acide sulfurique ont été synthétisé. La sulfonation par l'acide sulfurique suivi par un lavage dans l'eau bouillante puis un prétraitement thermique à 300°C sous azote, de ces matériaux aboutissent au meilleur catalyseur en termes d'activité/stabilité.
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46

Leroux, Denis. "Polystyrène sulfoné supporté sur silice poreuse : greffage et activité en catalyse acide." Lyon 1, 1994. http://www.theses.fr/1994LYO10290.

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Des catalyseurs polymeres supportes constitues de polystyrene sulfone greffe sur une silice poreuse ont ete synthetises, afin d'etudier le mecanisme de greffage, et l'influence du taux de recouvrement et de la masse molaire du polymere greffe sur l'activite catalytique. La strategie generale de greffage consiste a faire reagir les silanols de la silice sur un agent de couplage difonctionnel du type thioalcoxysilane dont la fonction thiol est active dans une reaction de transfert radicalaire. Deux voies de greffage ont ete etudiees. Le procede from consiste a faire croitre le polymere a partir de radicaux lies a la surface. L'analyse des masses molaires par gpc du polymere greffe (apres elimination de la silice) a revele une distribution des masses tres large. Les diagrammes de gpc ont ete reproduits par calcul. Un mecanisme du greffage from et des valeurs de constantes de vitesses ont ete proposes. Le procede onto fait appel a une reaction de condensation entre un polymere alcoxysilyterminal et les silanols de la silice, le polymere etant prealablement fonctionnalise en phase homogene par une reaction de transfert. Une addition progressive de cet agent permet de synthetiser des chaines polymeres de taille definie et a distribution de masses etroite. Des phenomenes de selection sterique lors du greffage ont ete mis en evidence. Le polymere a ete caracterise par rmn #1h, rmn#2#9si et ir. Le polymere greffe a ete sulfone par le complexe so#3-tep, ce qui a permis d'obtenir des catalyseurs actifs en catalyse acide. Leur capacite a ete mesuree par titrage, atg et analyse elementaire. Trois tests catalytiques, differant par la polarite des reactifs, ont ete selectionnes. Une relation entre l'activite et la structure du polymere greffe (longueur de chaine et taux de recouvrement) a ete mise en evidence. L'etude des stabilites chimique et thermique du catalyseur est egalement abordee
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47

Al-Mahasneh, Qusai M. "In-vitro/in-vivo correlation of the nature of excreted species after chelation therapy with 2,3-dimercaptopropane-1-sulfonic acid." Thesis, University of Surrey, 2001. http://epubs.surrey.ac.uk/770150/.

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Treatment of lead poisoning relies primarily on chelation therapy. The sodium salt of (R,S)-2,3-dimercapto-l-propanesulfonic acid (DMPS, DimavalL ®) is a water-soluble analogue of British Anti-Lewisite (BAL). Its oral dosage form is considered effective for the diagnosis and treatment of mercury poisoning (Aposhian et a!., 1995). In adults, therapeutically successful attempts have been reported for the treatment of chronic lead poisoning with DMPS (Anatovskaya, 1962). In children having chronic lead poisoning, the efficacy of DMPS was noted following a 5-day therapy (Chisholm & Thomas, 1985). Despite its current use in chelation therapy for the treatment of lead poisoning, detailed chemical characterization and/or investigation of the resulting complexes has not been fully investigated. DMPS and its complexes with lead are electro active, consequently have been investigated using electro analytical techniques. This present work was designed with the aim of (a) investigating the in-vitro complexing behavior of DMPS with lead at simulated physiological conditions, (b) in-vivo investigation of the chelation therapy of low and highly exposed subjects (workers). Electroanalytical techniques including: Voltammetry at the Dropping Mercury electrode, Differential Pulse Polarography (DPP), Anodic Stripping Voltammetry (ASV), and Cathodic Stripping Voltammetry (CSV), have been employed for investigating the complexing properties ofDMPS. Application of the methods suggested by Deford-Hume and ShumanWoodward for measuring stability constants of metal complexes, showed that the formed Pb:DMPS complex could be a labile coordination complex having a formation constant ofKf= 2.66xI04 • In addition, the results demonstrated that the Pb:DMPS species was much weaker than that formed between Pb2 + and EDTA (Kf = 1.25xI018 ). This may indicate that the mobilized lead from soft tissues and bone after chelation may have involved mechanisms other than complex formation. The in-vitro results demonstrated that electroanalytical techniques proved to be highly sensitive and selective for investigating both lead as well as DMPS levels in biological fluids. However, after chelation optimizing the media to enhance selectivity was necessary. Upon titration of DMPS versus lead or alternatively lead versus DMPS, the results showed that lead did not form a stable coordination complex. However, a compound with enough stability was formed which mobilized lead from body stores as demonstrated by levels of lead in urine measured after a single oral dose of DMPS (100 mg/ 3 capsules). Additionally, after dosing of exposed subjects classified as having low and high lead body burden, in-vivo findings showed that lead was substantially chelated after dosing with 100 mg DMPS/ 3 capsules. However, the lead-DMPS complex was not detected in urine and hence was regarded as a labile coordination complex. The latter finding compared well with in-vitro studies.
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48

Brouty, Marie-Sophie. "Recherche de nouveaux catalyseurs acides supportés de type polyphénylsilsesquioxanes chlorés sulfonés greffés sur silices." Lyon 1, 1995. http://www.theses.fr/1995LYO10135.

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Objectif: ce travail a pour objectif l'elaboration de nouveaux catalyseurs acides supportes thermostables de type polyphenylsilsesquioxanes respectivement non substitues, mono et dichlores, greffes sur silices mesoporeuses puis sulfones. Les effets de la longueur de la chaine polymere et de la presence de chlore sur les noyaux aromatiques sont consideres lors des differentes etapes de synthese. Les performances catalytiques des materiaux obtenus sont estimees au moyen de la reaction de decomposition du methyl-tertio-butyl-ether (mtbe), en reacteur lit fixe. Resultats: nous observons que la presence de substituants sur les noyaux aromatiques limite les degres de polymerisation. Suite a l'etude des reactions de greffage grace a l'utilisation de la methodologie des plans d'experiences, d'excellents taux de recouvrement sont atteints avec les entites de faible masse. En revanche, les rendements de sulfonation sont peu eleves et les reactions s'accompagnent de la perte partielle des centres fonctionnalisables. Mais, l'activite catalytique et les selectivites des materiaux synthetises sont comparables a celles des meilleurs catalyseurs classiques. Ces performances resultent essentiellement de la modification de la structure superficielle de la silice provoquee par l'action de l'agent sulfonant
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49

Schultz, Spencer Albert. "An Investigation into the Use of Density Functional Theory (DFT) Calculations for Predicting Vibrational Transitions for Perfluroinated Sulfonic Acid (PFSA) Ionomer Membranes." Thesis, Virginia Tech, 2019. http://hdl.handle.net/10919/87470.

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Perfluorinated sulfonic acid (PFSA) ionomer membranes demonstrate great potential for use in proton exchange membrane fuel cells (PEMFCs) due to their favorable electronic properties and excellent efficiency. However, the assignment of key vibrational transitions such as the symmetric sulfonate and ether stretches is not yet fully understood depriving researchers of a quick and simple technique for analyzing morphological changes. The symmetric sulfonate stretch could be used to track changes in the ionic clusters formed within the membrane while the ether stretch will provide insight into the largely semi-crystalline PTFE phase. Alterations in either regime will affect both ion transport and mechanical properties and produce a major shift in device performance. This study focused on predicting the vibrational transitions for Aquivion, 3M PFSA, and Nafion using density functional theory (DFT) with the bulk being performed using the same functional and basis set combination, B3LPY/6-31+G*. For all three ionomers, the predicted vibrational transitions were affected by changes in both the conformer and solvation method with water being used as the solvent. Despite the noted changes, both vibrational transitions were determined to be within the range of 970-1100 cm-1 with the symmetric sulfonate stretch present at around 970-1010 cm-1 and the ether stretch observed at around 1050-1100 cm-1 with solvation present. While the calculated peak positions mirror those found in the experimental spectra within the literature, the traditional normal mode assignments do not match those predicted by our calculations. However, recent studies have hypothesized that these vibrational transitions are coupled, which could explain why they have been so difficult to assign.
Master of Science
Perfluorinated sulfonic acid (PFSA) ionomer membranes show great promise for use in proton exchange membrane fuel cells (PEMFCs) due to their excellent efficiency. However, the current techniques used to determine changes in structural configurations require sophisticated equipment and trained personnel to operate. Simpler techniques exist wherein the vibrations of certain bonds can be measured upon exposure of the sample to measured amounts of infrared light. The problem with this technique is that researchers currently do not fully understand at what wavelengths certain portions of the polymer known as functional groups will vibrate. These vibrations are also known as vibrational transitions. This study was undertaken to predict through numerical solutions to the Schrödinger equation at what wavelengths two particular vibrational transitions would occur for three common ionomers, Aquivion, 3M PFSA, and Nafion. For all three structures, the positions of these transitions mirrored that observed within the literature although the functional groups assigned to these positions did not match with those identified by our calculations. However, recent studies have indicated that these vibrational transitions occur at the same positions, which could explain why they have been so difficult to assign.
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50

CAPET, MARC. "Synthese d'amines allyliques : oxydation de sulfones." Paris 6, 1986. http://www.theses.fr/1986PA066547.

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L'amination allylique des olefines est catalysee par le cuivre ; application a la synthese de la gabaculine en 4 etapes. Les regio- et stereoselectivite de cette reaction sont comparees a celles de l'acetoxylation de kharasch et de sosnovsky. Des sulfones sont oxydees par des complexes peroxydique du molybdene en hydroxysulfones a squelette carbone symetrique
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