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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Construction et étude de composés fluorescents à base d'unités hydroxyphényl-s-triazines et boradiazaindacènes / Synthesis and studies of fluorescent dyes based on hydroxyphenyl-s-triazines and boradiaza-s-indacenes units

Rihn, Sandra 13 June 2013 (has links)
Les travaux réalisés dans le cadre de la thèse avaient pour but la synthèse de nouveaux fluorophores basés sur les unités BODIPYs et hydroxyphényl-s-triazines. Pour être utilisées comme sondes efficaces dans des applications en chimie et en biologie, les chromophores doivent présenter une forte brillance et des rendements quantiques de fluorescence élevés, une modulation aisée de ses propriétés optiques ainsi qu’une bonne stabilité chimique et photochimique. Une stratégie originale et efficace a été développée pour l’obtention de dérivés d’o-hydroxyphényl-s-triazine. Ces derniers présentent des déplacements de Stokes anormalement élevés ayant pour origine un transfert de proton intramoléculaire ultrarapide à l’état excité (ESIPT). L’extension du système π-conjugué sur les différentes plateformes de départ a été réalisée par couplages pallado-catalysés et/ou condensation de Knoevenagel, permettant ainsi d’accéder à une large gamme spectrale en absorption et en émission. Le développement d’une nouvelle voie de synthèse à permis l’obtention d’oligo-BODIPYs par couplage oxydant réalisé en associant PIFA et un acide de Lewis. Toutes les propriétés photophysiques des nouvelles sondes ont été étudiées et ont fait l’objet de discussions détaillées. / The study undertaken in this thesis was the engeneering of new fluorescent dyes based on BODIPY and o-hydroxyphenyl-s-triazine units. The focus has been on the development of dyes displaying large absorption cross sections, emission wavelength tunability, high photostability and fluorescent quantum yields by using original synthetic strategies. As a part of our research program on the design of novel fluorescent dyes exhibiting large Stokes shifts, we developped an efficient method for the synthesis of o-hydroxyphenyl-s-trazine for which an anormalous emission was observed due to an intramolecular proton transfert in the excited state (ESIPT process). The fine tuning of the absorption and emission wavelength for both plateforms were achieved by extension of the π-conjugated system with aryl and alkyl moieties using palladium cross coupling or via a styryl linkage using Knoevenagel condensation. Another strategy to enhance the fluorescence performances consists in the rigidization of the plateforms. Various oligo-BODIPYs have been obtained by an unprecedented oxydative coupling reaction using Phenyliodine(III)bis(trifluoroacetate) (PIFA) in conjunction with a Lewis acid. All compounds spectral characteristics were investigated and their photophysical properties discussed.
2

A busca de um método espectrofotométrico com complexos de rutênio para estimação quantitativa da 1,3,5-triazina-1,3,5-(2H,4H,6H)-trietanol residual usada para eliminação do H2S presente no refino do petróleo / The search for a spectrophotometric method with ruthenium complexes for the quantitative estimation of residual 1,3,5-triazine-1,3,5 (2H, 4H, 6H) -trietanol used to eliminate the H2S present in the petroleum refining

Tasso, Carlos Roberto Batista 26 February 2016 (has links)
Nesse trabalho foi estudada uma técnica para a detecção de OHTC na água salina. Descobriu-se que certos complexos de rutênio em determinados valores de pH reagem com a molécula de OHTC e isto é detectável por espectrofotometria UV-Vis. Foram estudados os complexos fac-[RuCl2(S-DMSO)3(O-DMSO)] (complexo 1), {[(DMSO)2H][trans-RuCl4(DMSO)2]} (complexo 2) e cis-[RuCl2(bpy)2].2H2O (complexo 3). O complexo 1 possui um dos ligante (O-DMSO) que pode ser substituído pelo OHTC. Já o complexo 2 possui um dos ligantes (S-DMSO) na posição trans um ao outro, e o complexo 3 possui os 2 íons Cl- para tal finalidade. Determinou-se que o complexo 1 é viável, mesmo em presença de sais presentes na água do mar. Assim a reação foi realizada em função do tempo, variação do pH, temperatura e concentração de OHTC. Nos outros dois complexos os estudos foram realizados sem a variação da temperatura e concentração de OHTC. / p>In this work we studied a technique for detection of OHTC in water. It was discovered that complexes involving ruthenium, on determined pH values, react with the OHTC molecule and this is detectable by UV-VIS spectroscopy. The complexes fac-[RuCl2(S-dmso)3(O-dmso)] (complex 1), {[(DMSO)2H][trans-Ru(DMSO)2Cl4]} (complex 2), and cis-[RuCl2(bpy)2].2H2O (complex 3) were studied. The complex 1 present one position ( O - DMSO) which can be substituted by the OHTC. Additionally, the complex 2 present two ligands ( S- DMSO) trans between each other, and the complex 3 present two chloride ions for the same porpose of complex 1 respectively. It was determined that the complex 1 was able to react with OHTC even in presence of the salts present in sea water. Thereby, the reaction involving complex 1 and OHTC was monitored in function of the time, pH, temperature, and finally concentration of OHTC. On the other two complexes, the reaction was studied without variation of temperature and concentration of OHTC.
3

A busca de um método espectrofotométrico com complexos de rutênio para estimação quantitativa da 1,3,5-triazina-1,3,5-(2H,4H,6H)-trietanol residual usada para eliminação do H2S presente no refino do petróleo / The search for a spectrophotometric method with ruthenium complexes for the quantitative estimation of residual 1,3,5-triazine-1,3,5 (2H, 4H, 6H) -trietanol used to eliminate the H2S present in the petroleum refining

Carlos Roberto Batista Tasso 26 February 2016 (has links)
Nesse trabalho foi estudada uma técnica para a detecção de OHTC na água salina. Descobriu-se que certos complexos de rutênio em determinados valores de pH reagem com a molécula de OHTC e isto é detectável por espectrofotometria UV-Vis. Foram estudados os complexos fac-[RuCl2(S-DMSO)3(O-DMSO)] (complexo 1), {[(DMSO)2H][trans-RuCl4(DMSO)2]} (complexo 2) e cis-[RuCl2(bpy)2].2H2O (complexo 3). O complexo 1 possui um dos ligante (O-DMSO) que pode ser substituído pelo OHTC. Já o complexo 2 possui um dos ligantes (S-DMSO) na posição trans um ao outro, e o complexo 3 possui os 2 íons Cl- para tal finalidade. Determinou-se que o complexo 1 é viável, mesmo em presença de sais presentes na água do mar. Assim a reação foi realizada em função do tempo, variação do pH, temperatura e concentração de OHTC. Nos outros dois complexos os estudos foram realizados sem a variação da temperatura e concentração de OHTC. / p>In this work we studied a technique for detection of OHTC in water. It was discovered that complexes involving ruthenium, on determined pH values, react with the OHTC molecule and this is detectable by UV-VIS spectroscopy. The complexes fac-[RuCl2(S-dmso)3(O-dmso)] (complex 1), {[(DMSO)2H][trans-Ru(DMSO)2Cl4]} (complex 2), and cis-[RuCl2(bpy)2].2H2O (complex 3) were studied. The complex 1 present one position ( O - DMSO) which can be substituted by the OHTC. Additionally, the complex 2 present two ligands ( S- DMSO) trans between each other, and the complex 3 present two chloride ions for the same porpose of complex 1 respectively. It was determined that the complex 1 was able to react with OHTC even in presence of the salts present in sea water. Thereby, the reaction involving complex 1 and OHTC was monitored in function of the time, pH, temperature, and finally concentration of OHTC. On the other two complexes, the reaction was studied without variation of temperature and concentration of OHTC.
4

Enlargement of a Modular System—Synthesis and Characterization of an s-Triazine-Based Carboxylic Acid Ester Bearing a Galactopyranosyl Moiety and an Enormous Boron Load

Kellert, Martin, Lönnecke, Peter, Riedl, Bernd, Koebberling, Johannes, Hey-Hawkins, Evamarie 11 April 2023 (has links)
The amount of boron accumulated in tumor tissue plays an important role regarding the success of the boron neutron capture therapy (BNCT). In this article, we report a modular system, combining readily available starting materials, like glycine, 1,3,5-triazine and the well-known 9-mercapto-1,7-dicarba-closo-dodecaborane(12), as well as alpha-d-galactopyranose for increased hydrophilicity, with a novel boron-rich tris-meta-carboranyl thiol.
5

Construction et étude de composés fluorescents à base d'unités hydroxyphényl-s-triazines et boradiazaindacènes

Rihn, Sandra 13 June 2013 (has links) (PDF)
Les travaux réalisés dans le cadre de la thèse avaient pour but la synthèse de nouveaux fluorophores basés sur les unités BODIPYs et hydroxyphényl-s-triazines. Pour être utilisées comme sondes efficaces dans des applications en chimie et en biologie, les chromophores doivent présenter une forte brillance et des rendements quantiques de fluorescence élevés, une modulation aisée de ses propriétés optiques ainsi qu'une bonne stabilité chimique et photochimique. Une stratégie originale et efficace a été développée pour l'obtention de dérivés d'o-hydroxyphényl-s-triazine. Ces derniers présentent des déplacements de Stokes anormalement élevés ayant pour origine un transfert de proton intramoléculaire ultrarapide à l'état excité (ESIPT). L'extension du système π-conjugué sur les différentes plateformes de départ a été réalisée par couplages pallado-catalysés et/ou condensation de Knoevenagel, permettant ainsi d'accéder à une large gamme spectrale en absorption et en émission. Le développement d'une nouvelle voie de synthèse à permis l'obtention d'oligo-BODIPYs par couplage oxydant réalisé en associant PIFA et un acide de Lewis. Toutes les propriétés photophysiques des nouvelles sondes ont été étudiées et ont fait l'objet de discussions détaillées.
6

Biomineralization of atrazine and analysis of 16S rRNA and catabolic genes of atrazine-degraders in a former pesticide mixing and machinery washing area at a farm site and in a constructed wetland

Douglass, James F. January 2015 (has links)
No description available.

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