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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.
71

Di- and tetratopic pyridine appended cyclidenes as "molecular tweezers" : structure and carboxylic acid NMR binding studies /

Disch, Jeremy S. January 2004 (has links)
Thesis (Ph.D.)--Tufts University, 2004. / Adviser: Elena V. Rybak-Akimova. Submitted to the Dept. of Chemistry. Includes bibliographical references (leaves 381-387). Access restricted to members of the Tufts University community. Also available via the World Wide Web;
72

The effects of morphactins on some aspects of plant growth /

Firn, Richard David. January 1968 (has links) (PDF)
Thesis (M. Ag. Sc.)--University of Adelaide Department of Plant Physiology, 1968. / Includes bibliographical references.
73

Caracterização preliminar das emissões de aldeídos e ácidos carboxílicos em veículos do ciclo Otto e do ciclo Diesel com uso de combustíveis fósseis e renováveis / Preliminary characterization of emissions of aldehydes and carboxylic acids in vehicles Otto and Diesel cycle with the use of fossil fuels and renewable

Edson Elpidio Neto 01 July 2009 (has links)
O crescimento excessivo da frota veicular mundial tem feito com que milhares de toneladas de poluentes sejam lançadas na atmosfera diariamente em todo o globo, no Brasil a frota de veículos atingiu aproximadamente 54 milhões de unidades, e tem aumentado significativamente em vários estados, segundo o DETRAN (Departamento Estadual de Transito de São Paulo) o estado conta hoje com aproximadamente 19,5 milhões de veículos, 6,5 milhões só na capital, onde são emplacados aproximadamente mil veículos por dia, este crescimento tem causado episódios críticos de poluição do ar nos centros urbanos. Dentre os poluentes lançados na atmosfera de origem veicular, encontram-se os aldeídos e os ácidos carboxílicos, (objetos de estudo deste trabalho), essas substâncias são de suma importância para saúde humana, e participam nas reações fotoquímicas de formação de ozônio na baixa troposfera. Desde a implantação do PROCONVE (Programa de Controle de Poluição do Ar por Veículos Automotores) em 1988, medidas como a redução dos limites de emissão, novas tecnologias na fabricação de veículos automotores, redução da porcentagem de enxofre no diesel, combustíveis renováveis, entre outras, e programas como a Inspeção veicular na cidade de São Paulo criada a partir de 2009, tem sido tomadas visando à constante melhoria na qualidade do ar. Dentre os combustíveis renováveis atualmente utilizados, o biodiesel tem se destacado, tendo em vista o grande consumo de diesel utilizado como fonte de energia no Brasil. Atualmente foram incorporados 2% de biodiesel ao diesel comercial, e antecipando a meta para 2013, possivelmente já no ano de 2010 a porcentagem será de 5%. O objetivo deste trabalho é a caracterização preliminar de aldeídos e ácidos carboxílicos na emissão de veículos do ciclo Otto e do ciclo diesel, utilizando combustíveis fósseis e renováveis. Para a realização deste trabalho foram utilizados três veículos, sendo dois do ciclo Otto e um do ciclo diesel. Os testes foram realizados em dinamômetro de chassis conforme norma ABNT NBR 6601 e ABNT NBR 12026, o método para amostragem dos ácidos carboxílicos foi validado e estabelecido conforme item 6.2 deste trabalho. Nos veículos do ciclo Otto, foram utilizados como combustíveis, a gasolina pura, gasolina com 22% de AEAC (Álcool etílico anidro combustível) e AEHC (álcool etílico hidratado combustível). No veículo do ciclo diesel foram utilizados como combustíveis o diesel comercial com 2% de biodiesel e biodiesel puro de soja. Os resultados obtidos indicaram uma emissão de ácidos carboxílicos 2,5 vezes maior para os testes realizados com os veículos do ciclo Otto, e 5,5 vezes superior para os aldeídos nos resultados dos testes realizados com o veículo do ciclo diesel. A média de todos os resultados obtidos na realização deste trabalho com os veículos do ciclo Otto e do ciclo diesel, utilizando combustíveis fósseis e renováveis, indicaram emissão 3,2 vezes superior dos poluentes pesquisados na utilização de combustíveis renováveis. Estudos com maior número de amostras, e diversificações nas categorias dos veículos devem ser realizados a fim de se detalhar o perfil destes poluentes na emissão veicular com o uso de combustíveis fósseis e renováveis. / The global automotive fleet is emitting thousands of tons of air pollutants daily all over the planet; in Brazil, the domestic fleet reached 54 million vehicles. According to DETRAN (São Paulo state traffic department), the state of São Paulo has 19,5 million vehicles and 6,5 million in São Paulo city, where a thousand new vehicles daily are registered. This fleet growing up is causing critical air pollution situations in metropolitan areas. Among the major automotive air pollutants are aldehydes and carboxylic acids, both are the subject of this study. These substances play an important role for human health and they take place at photochemical reactions generating ozone in low troposphere. Since the beginning of PROCONVE (National Automotive Pollution Control Regulation) in 1988, measures has been taken like emission regulation, development of new automotive technologies, reduction of sulfur content in diesel fuel, renewable fuels and inspection of in use vehicles. Among the fuels from renewable sources currently in use, the biodiesel plays an important role, because diesel is the most used energy source. Currently, with the enforcement of the law number 11097, from January 13rd of 2005, 2% of biodiesel must be added in the commercial diesel and until 2013 this addition will rise to 5%. The subject of this study is the determination of emission profile of aldehydes and carboxylic acids in vehicles powered by Otto and diesel engines using fossil and renewable fuels. In this study were used three vehicles, two of them powered by Otto engines and one sample with diesel engine. The tests were performed in vehicle chassis dynamometer in accordance of the standards ABNT NBR 6601 and ABNT NBR 12026. The method for sampling and evaluation of carboxylic acids was validated and established in article 6.2 of this study. Otto vehicles were tested with 100% gasoline, gasoline plus 22% of anhydrous ethanol and 100% Ethanol. Diesel vehicle were tested with commercial diesel plus 2% biodiesel and 100% soy biodiesel. The results indicates an average 3,2 times higher emission of aldehydes and carboxylic acids when the samples were tested with renewable fuels. Tests with a higher number of samples and variation in vehicle types should be performed in order to provide a more precise profile of these pollutants emission using fossil and renewable fuels.
74

Steric Effect of Carboxylate Ligands on Pd-Catalyzed C-H Bond Arylation Reactions / パラジウム触媒を用いた炭素-水素結合アリール化反応におけるカルボキシラート配位子の立体効果

Tanji, Yutaka 23 March 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22457号 / 工博第4718号 / 新制||工||1737(附属図書館) / 京都大学大学院工学研究科物質エネルギー化学専攻 / (主査)教授 大江 浩一, 教授 中村 正治, 教授 中尾 佳亮 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM
75

The complexes of palladium (II) and nickel (II) with cycloalkanecarboxylic acid

Yeh, Thaimos E. T. 01 January 1973 (has links)
Although some organic hydroxy acid complexes of palladium(II) and nickel(II) have been described (1-9), crystalline palladium(II) and mickel(II) dicycloalkanecarboxylates have not been reported. The interaction of a palladium salt such as NA2PdCl4 or a nickel salt such as NiCl2·6H2 with cycloalkane carboxylic acids which contain 3, 4, 5, 6, and 7 carbons produces deep green carboxylates with palladium(II) and yellowish green carboxylates with nickel(II).
76

Analysis of Perfluoroalkyl Carboxylic Acids in Composite Dietary Samples by Gas Chromatography/Mass Spectrometry with Electron Capture Negative Ionization / ガスクロマトグラフィー負化学イオン化質量分析による食事中のフッ素化カルボン酸の分析

Fujii, Yukiko 24 March 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(社会健康医学) / 甲第18193号 / 社医博第54号 / 新制||社医||8(附属図書館) / 31051 / 京都大学大学院医学研究科社会健康医学系専攻 / (主査)教授 中山 健夫, 教授 玉木 敬二, 教授 川上 浩司 / 学位規則第4条第1項該当 / Doctor of Public Health / Kyoto University / DFAM
77

Assessing the potential of carboxylic acids as inhibitors of glycation

Gao, Hong Ying, 1967- January 2008 (has links)
No description available.
78

The Electronic Spectrum of (-)-S-(pS)-2,5,3',6'-Tetrahydro-2.2-Paracyclophane-2-Carboxylic Acid

Hall, Lindsey 05 1900 (has links)
A new, efficient route was used in the synthesis of [2.2]-paracyclophane-2-carboxylic acid. The acid as then resolved and the Birch reduction performed yielding one enantiomer of tetrahydro-[2.2]-paracyclophane-2-carboxylic acid. The ultraviolet spectrum of tetrahydro-[2.2]-paracyclophane- 2-carboxylic acid in isopenthane shows one absorption at 206 nm (Emax = 5,271). There are three bands observed in the circular dichroism spectrum in isopentane at 236 nm ([] = 1.8 X 104), 201 nm ([0] = -16 X 104) and a positive band indicated below 180 nm but not observed. The bands were assigned and possible reasons for the occurrence of a mr'r* transition at unexpectedly long wavelengths are discussed.
79

The preparation of coordination compounds of rhodium (III) with cycloalkanecarboxylic acid

Alameda, Robert Adrian 01 January 1977 (has links) (PDF)
The purpose of this study was to prepare and characterize the coordination compounds produced by the reaction of five cycloalkanecarboxylic acids and a rhodium salt. The five acids that furnished the ligands were: cyclopropanecarboxylic acid, cyclobutanecrboxylic acid, cyclopentanecarboxylit acid, cyclohexanecarboxylic acid, and a cycloheptanecarboxylic acid. The rhodium (Ill) ion was provided by the salt Na3RhCl6•12H20, A survey of the available literature indicated that these rhodium (Ill) cyclo-alkane carboxylates had not previously been prepared.
80

Supramolecular studies with functionalised group 15 ligands

Sanchez-Ballester, Noelia M. January 2010 (has links)
This thesis has been divided into five sections. The first chapter introduces the main themes of this thesis, including the description of the concepts of supramolecular chemistry, crystal engineering, hydrogen bonding and graph set analysis. The final section of chapter one describes a typical X-ray experiment used to determine the structures of the compounds presented in this thesis. Chapter two describes the synthesis and single crystal structures of copper(I) complexes with pyridine- and pyrazine-carboxylic acids. A series of novel solvent inclusion compounds of copper(I) complexes with pyridine- and pyrazine-carboxylic acids and the hydrogen bonding patterns adopted are also discussed. Chapter three reports the potential uses of boronic acids as building blocks for the design of novel solid-state architectures utilising hydrogen bonds. Novel copper(I) pyridine-/pyrazine-carboxylate complexes with boronic acid co-crystals are presented in which the heterodimeric boronic carboxylate R22(8) ring motif is present in all cases. Chapter four discusses the synthesis of novel ditertiary phosphines bearing functional groups with hydrogen bonding potential either via a three-step or single step synthetic route which involves a well known method of reductive amination followed by an efficient Mannich-based condensation. Complexation studies of these P,P-bidentate ligands with various transition metal centres such as Pt(II), Mo(0), Ru(II) and Au(I) are also presented. The effect on the structural motifs observed in these series of compounds by the regioselective incorporation of functional groups with potential hydrogen bonding capability such as hydroxyl and amide is also given. Finally, chapter five contains the synthesis and coordination studies of new phosphorus donor ligands leading to ideas for further work.

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