Dissertations / Theses: 'Compound. eng'

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Caetano, Mayra Cristina Teixeira. "Substratos e níveis de irrigação na formação de porta-enxerto utilizando limão-cravo /." Jaboticabal : [s.n.], 2011. http://hdl.handle.net/11449/88264.

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Orientador: João Antonio Galbiatti
Banca: Carlos Eduardo Angeli Furlani
Banca: Emerson Fachini
Resumo: O desenvolvimento dos centros urbanos tem conduzido a um aumento desordenado na geração de resíduos e conseqüente poluição ambiental. Tendo em vista o potencial agronômico dos resíduos gerados pelas cidades, o presente trabalho teve por objetivo verificar a influência do composto de lixo (CL), composto de poda de árvore (CP) e substrato comercial (SC), associados a diferentes lâminas de irrigação no desenvolvimento de porta-enxerto (limão-cravo) de citros. O delineamento experimental adotado foi em blocos casualizados em um esquema fatorial 6x3, sendo seis diferentes combinações de substratos: S1 - 100% SC; S2 - 80% SC + 20% CP; S3 - 60% SC + 30% CP + 10% CL; S4 - 40% SC + 40% CP + 20% CL; S5 - 20% SC + 50% CP + 30% CL e S6 - 60% CP + 40% CL associados a três lâminas de irrigação: 50% (I1), 100% (I2) e 150% (I3) da evapotranspiração diária medida pelo atmômetro. Os parâmetros avaliados das plantas foram: altura, número de folhas, diâmetro do caule, matéria fresca aérea e matéria seca aérea. Os resultados permitiram concluir que a irrigação abaixo da evaporação medida pelo atmômetro causaram efeito negativo no desenvolvimento das plantas e que a reposição de água com 150% (I3) foi a que favoreceu o desenvolvimento. Os substratos S2, o qual se utilizou 80% de SC associado à 20% CP foi os que proporcionou melhor desenvolvimento dos porta-enxertos. Os substratos com porcentagem de composto de lixo superior a 30% mostraram-se inadequados para o desenvolvimento dos porta-enxertos
Abstract: The development of urban centers has led to an inordinate increase in the generation of waste and consequent environmental pollution. Considering the agronomic potential of the waste generated by cities, the present work objective was to check the influence of garbage compound (GC), pruning of tree (PT) and commercial substrate (CS), associated to different irrigation blades in the rootstocks (Rangpur Lime) citros development. The experimental delineation adopted was in random blocks in a fatorial scheme 6x3, being six different substrates combinations: S1 - 100% CS; S2 - 80% CS + 20% PT; S3 - 60% CS + 30% PT + 10% GC; S4 - 40% CS + 40% PT + 20% GC; S5 - 20% CS + 50% PT + 30% GC e S6 - 60% PT + 40% GC associated to different irrigation blades: 50% (I1), 100% (I2) e 150% (I3) of the daily evapotranspiration measured by the atmometer. The evaluated plants parameters were: height, leaves number, stem diameter, fresh matter and dry matter of the air part. The results allowed to conclude that the irrigation below the evaporation measured by the atmometer caused negative effect in the plants development and the water replacement with 150 % (I3) was the one that favored the development. The substrates S2, which is used 80% of SC associated with 20% CP was that the enhanced growth of the rootstocks. The substrates with garbage compound percentage superior to 30 % appeared unsuitable for the rootstocks development
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Tarrento, Gilson Eduardo. "Processo de produção de composto orgânico derivado de resíduos industriais com aplicação no cultivo de alface /." Bauru : [s.n.], 2008. http://hdl.handle.net/11449/136665.

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Orientador: José Carlos Martinez
Banca: Roberto Lyra Villas Bôas
Banca: Adílson Renófio
Resumo: Em todo processo, é presumível a condição da geração de resíduos, sendo cada vez mais premente a busca de alternativas para destinação correta destes resíduos. Neste sentido, foi realizado um experimento com a compostagem de diferentes resíduos sólidos industriais provenientes do processo de extração do princípio ativo de plantas medicinais. O experimento constitui-se na mistura, em proporções diferentes dos resíduos: a) Resíduo orgânico - gerado a partir do esmagamento da planta de jambú (Spilanthes oleracea), após a extração do princípio ativo, b) lodo físico-químico, gerado a partir do processo de tratamento de água e c) lodo biológico, oriundo do esgoto da empresa. Este trabalho teve como objetivos gerar uma alternativa, ambientalmente correta, para o reaproveitamento do lodo físico-químico e verificar o efeito agronômico dos compostos resultantes na produção da alface. O processo de compostagem deu-se no período de 120 dias. A temperatura das pilhas foi medida diariamente, em três diferentes profundidades. Ao final, o composto foi pesado e avaliou-se, em média, o rendimento. Na segunda fase do experimento, buscando avaliar o efeito agrônomico dos compostos sobre a produção da alface (Lactuca sativa L.), os materiais compostos foram dispostos em vasos, em casa de vegetação, formando um delineamento inteiramente casualizado (DIC), com fatorial 4 x 4, sendo o fator 1 formado por 4 tratamentos: composto 1 (C1 - 0% lodo - 100% jambú), composto 2 (C2 - 7% lodo - 93% jambú), composto 3 (C3 - 13% lodo - 87% jambú), composto 4 (C4 - 26% lodo - 74% jambú) e o fator 2 formado por 4 diferentes doses de compostos: (0, 45, 90 e 135 t ha-¹ ) e quatro repetições, totalizando 64 unidades experimentais. Nas avaliações realizadas após 45 dias do transplantio da alface, o tratamento C1 dose três (90 t ha-¹) apresentou os melhores resultados de rendimentos. Nos demais tratamentos, ocorreram um decréscimo...
Abstract: It is assumed that there is generation condition in every production process. Alternative ways for the correct destination of the residues has become essential. Therefore, an experiment on different industrial solid residues compound from medicinal plants active principle extration has been performed. The experiment was based on the mixture of the residues in different proportions: a) organic residue generated from jambu (Spilanthes oleracea) smashing after active principle extraction, b) physiochemic mud generated from water treatment process and c) biologic mud originated from the company sewage. This work aimed at generating an environmentally correct alternative for phisiochemic mud reutilization and verify the agronomic effects of the resulting compounds in lettuce production. The compounding process lasted 120 days. Piles temperature was measured in three different depths. At the end, the compound was weighed and the average yield was evaluated. In the second phase of the experiment we aimed at evaluating the compound agronomic effects on lettuce (Lactuca sativa L.) production. The compounded materials were placed ins vases in greenhouses in an entirely randomized order, with factorial 4 x 4. Factor 1 was formed by 4 treatments: compound 1 (C1 - 0% mud - 100% jambu), compound 2 (C2 - 7% mud - 93% jambu), compound 3 (C3 - 13% mud - 87% jambu), compound 4 (C4 - 26% mud - 74% jambu). Factor 2 was formed by 4 differente compound dosages: (0,45, 90 e 135 t ha-¹) and hour repetitions, totaling 64 experomental unities. Treatment C1, dosage 3 (90 t ha-¹) presented the best results in the evaluation 45 days after lettuce transplantation. In the remaining treatments there was alinear decrease in lettuce production. However, C4 that 26% mud in its composition was superior than those with 0 dosage of organic matter. Compound can be considered an environmentally correct alternative for these residues with the possibility of agronomic utilization.
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Cardozo, Mirian Tavares Dias. "Composto de lixo orgânico urbano na produção do pimentão irrigado em cultivo protegido /." Jaboticabal : [s.n.], 2012. http://hdl.handle.net/11449/100810.

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Orientador: João Antonio Galbiatti
Coorientador: Márcio José Santana
Banca: Américo Iorio Ciociola Júnior
Banca: Haroldo Silva Vallone
Banca: Carlos Eduardo Angeli Furlani
Banca: Rogério Teixeira de Faria
Resumo: Na produção de hortaliças é fator determinante a adubação aplicada nas dosagens corretas e a reposição de água no solo em quantidades ideais. A adubação com compostos orgânicos pode diminuir o custo da produção e proporcionar aumento da produtividade. O presente trabalho teve como objetivos determinar os efeitos das reposições de água de irrigação na produtividade, e a dosagem do composto de lixo a ser utilizada na cultura do pimentão quando cultivada em ambiente protegido. O experimento foi conduzido em estufa modelo arco com 280 m2. O delineamento experimental foi em blocos casualizados com 24 tratamentos em esquema fatorial de 6 x 4 (formas de adubação e reposição de água no solo, respectivamente). Quanto à adubação, foram seis formas: adubação mineral e adubação com composto de lixo orgânico (4 t ha-1, 8 t ha-1, 12 t ha-1 e 16 t ha-1), mais uma testemunha sem adição de adubos. Quanto às reposições de água no solo foram de 70%, 100%, 130% e 160% da lâmina necessária para elevar o solo à capacidade de campo. Foram determinados o número de frutos, altura das plantas, diâmetro do caule, eficiência do uso da água e a produtividade da cultura. Dentre os resultados, verificou-se que quando a reposição de água no solo foi efetuada integralmente (100% de reposição) a produtividade foi similar entre as adubações com composto de lixo orgânico de 16 t ha-1, 12 t ha-1 e 8 t ha-1
Abstract: In vegetables production, the correct dosages of applied fertilizer and replacement of water in the soil in optimal amounts is a determining factor. The fertilization with organic compounds can decrease the production cost and provide increased productivity. This study aimed to: determine the effects of different replacement of irrigation water in crop yield, and optimal dosage of organic compound to be used in sweet pepper when grown in a greenhouse. The experiment was conducted in a bow model greenhouse with 280 m2. The experiment was designed in randomized blocks with 24 treatments in a factorial arrangement of 6 x 4 (types of fertilization and water replacement in the soil, respectively). As for fertilization, it's used six forms: fertilization with mineral fertilizer and organic compound (4 t ha-1, 8 t ha-1, 12 t ha-1 and 16 t ha-1) and one as control, without addition of fertilizers. For the water replacement in the soil, it's used 70%, 100%, 130% and 160% of the blade to raise the soil at field capacity. It was determined the number of fruits, plants height, stalk diameter, efficiency of water use and crop productivity. Among the results, it was found that when the replacement of water in the soil was made in full (100% replacement) the productivity was similar between the fertilizer with organic waste compound of 16 t ha-1, 12 t ha-1 and 8 t ha-1
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Muraishi, Reginaldo Itiro. "Compostos orgânicos como substratos na formação de mudas de ipê amarelo [Tabebuia chrysotricha (Mart. ex DC) Standl.] irrigado com água residuária /." Jaboticabal : [s.n.], 2008. http://hdl.handle.net/11449/88286.

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Orientador: João Antonio Galbiatti
Banca: Jairo Augusto Campos de Araújo
Banca: Emerson Fachini
Resumo: A necessidade de se estudar a utilização do resíduo de podas de árvores é de grande importância ambiental para solucionar os problemas de resíduos sólidos gerados nas áreas urbanas junto com os resíduos de lixos domésticos. O estudo deste material foi avaliado com base no desenvolvimento de mudas de ipê-amarelo [Tabebuia Chrysotricha (Mart. ex DC.) standl.] cultivados em diferentes substratos e com 2 tipos de água para irrigação. O experimento foi instalada no setor de plasticultura do Departamento de Engenharia Rural da Faculdade de Ciências Agrárias e Veterinárias - UNESP, Campus de Jaboticabal. Foram realizados 2 experimentos, avaliados conjuntamente com delineamento experimental em blocos casualizados, de 8 substratos, 2 qualidades de águas e 4 repetições, totalizando 64 parcelas. Cada parcela foi composta por 30 plantas (5 linhas de 6 plantas), sendo consideradas como úteis, as 3 linhas de 4 plantas centrais da parcela. Para estudar o desenvolvimento das mudas de ipê amarelo, foram avaliadas a altura da parte aérea das plantas (H), diâmetro do colmo (D), matéria seca (MS) e composição química. As características de desenvolvimentos foram avaliadas aos 21, 42, 63 e 84 dias após a emergência das plantas. Da análise dos resultados concluiu-se que os substratos estudados promoveram diferenças significativas para altura média das plantas, diâmetro médio de colmo, acúmulo de matéria seca e teores de nutriente nas folhas em todos os períodos de avaliação. Houve interação positiva entre substrato e água de irrigação, para altura média das plantas e diâmetro médio de colmo aos 42, 63 e 84 dias após emergência e em todos nutrientes foliar. Os substratos 3 (5% composto lixo + 95% composto de poda, 4 (10% composto de lixo +90% composto de poda) e 5 (20% de composto de lixo + 80% composto de poda) e a água residuária apresentaram os melhores resultados no desenvolvimento das mudas de ipê amarelo.
Abstract: The need to study the use of waste pruning of trees is of great importance to solve the environmental problems of solid waste in the urban areas along with the waste of household waste. The study of these materials was evaluated with the development of seedlings of yellow-ipe [Tabebuia chrysotricha (Mart. ex DC.) Sandl.] in mixtures of different substrates and types of water for irrigation. The experiment was installed at the Department of Rural Engineering of de São Paulo University State, Campus of Jaboticabal. Two experiments were conducted, evaluated together with experimental design in randomized blocks of 8 substrates, 2 qualities of water and 4 repetitions, totaling 64 parcels. Each parcel was composed of 30 plants (5 rows of 6 plants) and is regarded as useful, the 3 lines of 4 plants of the central plot. Eight substrates were tested, resulting from the combination of commercial substrate, composed of household waste and composed of pruning of trees with 2 types of irrigation water (clean water and residuary) and 4 repetitions. To observe the development of seedlings of yellow-ipe, were evaluated the height of the shoots of plants, diameter of the stem, dry material and leaf analysis. The characteristics were evaluated at 21, 42, 63 and 84 days after the emergency. The analysis of results allowed to conclude that the substrates studied promoted significant differences in average height of the plants, stem diameter, dry material and leaf analysis in all periods of assessment. The interaction between substrate and water for irrigation were to average height and diameter of the plant stem at 42, 63 and 84 days after emergency and in all of leaf analysis nutrients. The substrates 3, 4 and 5 with residuary water showed the best results in the development of seedlings of yellow-ipe.
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Luengo, Arratta S. "Intramolecular ene reactions of functionalised nitroso compounds." Thesis, University College London (University of London), 2010. http://discovery.ucl.ac.uk/20237/.

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This thesis concerns the generation of geminally functionalised nitroso compounds and their subsequent use in intramolecular ene reactions of types I and II, in order to generate hydroxylamine derivatives which can evolve to the corresponding nitrones. The product nitrones can then be trapped in the inter- or intramolecular mode by a variety of reactions, including 1,3-dipolar cycloadditions, thereby leading to diversity oriented synthesis. The first section comprises the chemistry of the nitroso group with a brief discussion of the current methods for their generation together with the scope and limitations of these methods for carrying out nitroso ene reactions, with different examples of its potential as a powerful synthetic method to generate target drugs. The second chapter describes the results of the research programme and opens with the development of methods for the generation of functionalised nitroso compounds from different precursors including oximes and nitro compounds, using a range of reactants and conditions. The application of these methods in intramolecular nitroso ene reactions is then discussed. Chapter three presents the conclusions which have been drawn from the work presented in chapter two, and provides suggestions for possible directions of this research in the future. This work concludes with a formal account of the experimental procedures.

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Nascimento, João Paulo Reato. "Toxicidade de produtos sintetizados a partir de extratos de plantas e do bistrifluron para o cupim subterrâneo Coptotermes gestroi (Wasmann, 1896) (Isoptera; Rhinotermitidae) /." Rio Claro : [s.n.], 2009. http://hdl.handle.net/11449/99512.

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Orientador: Odair Correa Bueno
Banca: Marcos Roberto Potenza
Banca: Fabiana Elaine Casarin
Resumo: O cupim subterrâneo Coptotermes gestroi (WASMANN, 1896) é uma das principais pragas responsável por danos econômicos em estruturas de madeira nas áreas urbanas do litoral e interior do sudeste brasileiro. A metodologia mais empregada no controle de cupins subterrâneos é a aplicação direta de inseticidas no solo, porém esse tipo de tratamento não é destinado à eliminação da colônia e sim a formar uma barreira química entre a fonte de alimento que está sendo consumida e a colônia dos cupins. Essa barreira química também não evita que alados infestem prédios na época da revoada, pois eles não terão contato com os inseticidas. Essas infestações podem continuar sendo subterrâneas em porões de edificações ou podem ser aéreas, onde os cupins nidificam em espaços entre os andares dos edifícios, pois estes locais oferecem o ambiente ideal para os cupins com água, abrigo e alimento. Uma estratégia alternativa que visa à eliminação da colônia dos cupins subterrâneos é a utilização da metodologia de isca. Nas iscas o ingrediente ativo é incorporado a substratos que contenham celulose, sendo assim, a quantidade de inseticida usado é mínima, pois ele não pode ser repelente e precisa ter ação lenta e as partes não consumidas das iscas podem ser removidas depois do tratamento. No presente estudo foram realizados bioensaios laboratoriais com C. gestroi para avaliar a toxicidade de cinco substâncias que foram sintetizadas tendo como modelo a molécula da sesamina, sendo duas amidas e três compostos piperonílicos. Adicionalmente, foi analisado um inibidor de síntese de quitina, representado pelo bistrifluron. Os resultados revelaram que para as duas amidas e composto piperonílico 1, apesar de serem tóxicos, seriam necessários novos bioensaios com concentrações acima de 10 000 ppm para verificar se ocorre o aumento da dose ingerida pelos cupins.
Abstract: The subterranean termite Coptotermes gestroi (WASMANN, 1896) is a major urban pest that attacks wooden structures throughout southeastern Brazil. The most widely employed method to control subterranean termites is the direct application of insecticides on soil, however this method does not eliminate the colonies, but creates a chemical barrier between termites and their food. Moreover, this chemical barrier does not preclude infestation of buildings by alate reproductives during the reproductive season as they don't come in contact with the insecticides. The infestation may remain underground at basements or in the spaces between the stories of the buildings, as these sites offer the ideal habitat for termites with water, protection and food. An alternative strategy eliminating subterranean termite's colonies is the use of baits. In baits the insecticide is embedded in cellulose substrates, thus minimizing, the amount of insecticide used, which can't be repellent and has to have slow mode of action, generating easily removable unconsumed wastes. In this study, we performed laboratory bioassays with C. gestroi to evaluate the toxicity of five substances that were synthesized with a model of the molecule of sesamine, being two amides and three piperonyl compounds. Additionally, was analyzed a chitin synthesis inhibitor, represented by bistrifluron. The results showed that the two amides and piperonyl compound 1, although toxic, would have to be tested at concentrations above 10 000 ppm to verify if there is an increase in the uptake of insecticide. Piperonyl compounds 3 and 5 shown to be effective at the concentration of 10 000 ppm, but new bioassays would be needed to confirm this results. Bistrifluron proved efficient to be used in baits, although causing a reduction in the intake of food by termites, but didn't influence the effect of the insecticide... (Complete abstract click electronic access below)
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Rodrigues, Ana Paula. "Oxidação de compostos β-dicarbonílicos por peroxidase /." Araraquara : [s.n.], 2007. http://hdl.handle.net/11449/100721.

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Resumo: A terapia ADEPT (antibody-directed enzyme prodrug therapy) tem sido caracterizada, em vários estudos experimentais focalizados na destruição de células tumorais, como uma alternativa à fármacos citotóxicos sistêmicos (anti-proliferativos). Nesta técnica, o pró-fármaco é ativado por enzimas exógenas que são levadas à célula tumoral por meio de anticorpos monoclonais (Mab). Neste contexto, horseradish peroxidase (HRP) e ácido 3-indolacético (IAA) constituem um dos sistemas mais citados de enzima e pró-fármaco aplicados à destruição de células tumorais com conjugados HRP-Mab. Peroxidases são enzimas inespecíficas e várias moléculas podem ser oxidadas pela suas formas ativas HRP-l e HRP-ll no ciclo clássico da peroxidase, que é dependente de peróxido de hidrogênio ou hidroperóxidos orgânicos. Por outro lado, somente NADH, dihidroxifumarato e a auxina de planta IAA, têm sido descritos como substratos para HRP em reação independente de peróxido de hidrogênio. O objetivo deste trabalho foi estudar o mecanismo pelo qual compostos β-dicarbonílicos são oxidados por HRP e explorar suas aplicações. Foi demonstrado que os compostos dicarbonílicos 2,4-pentanodiona (PD) e 3-metil-2,4-pentanodiona (MePD) são eficientemente oxidados pela HRP, na ausência de peróxido, em tampão fosfato pH 7,4, consumindo oxigênio presente em solução, o que não ocorreu com outros compostos β-dicarbonílicos testados (dimedona e acetoacetato). Observou-se também, via espectrofotometria, durante a reação com PD e MePD, que a enzima nativa passou à sua forma HRP-lll, além disso, a reação produziu espécies reativas de oxigênio (ERO), detectadas por quimiluminescência dependente de luminol e fluorescência dependente de diclorofluoresceína. Também foram realizadas reações de consumo de oxigênio com outros compostos que possuem grupamento... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Antibody-directed enzyme prodrug therapy (ADEPT) has featured in several experimental studies focused on the destruction of tumor cells, as an alternative to systemic cytotoxic (antiproliferative) drugs. In this technique, the prodrug is activated by exogenous enzymes delivered to tumor cells via monoclonal antibodies (MAb). In this context, horseradish peroxidase (HRP) and indole-3-acetic acid (IAA) constitute one of the most often cited systems of enzyme and prodrug applied to destroy tumor cells with HRP - MAb conjugates. Peroxidases are unspecific enzymes and several molecules can be oxidized by the active forms HRP-I and HRP-II in the classic peroxidase cycle, which depends on hydrogen peroxide or organic hydroperoxides. On the other hand, only NADH, dihydroxyfumarate and the plant auxin IAA have been described as substrates for HRP in a reaction independent of hydrogen peroxide. The objective of this work was to study the mechanism by which β-dicarbonyl compounds are oxidized by HRP and explore possible applications. We demonstrated by measuring oxygen uptake, that the dicarbonyls PD (2,4-pentanedione) and 3-MePD (3-methyl-2,4-pentanedione) can also be oxidized by HRP in the absence of peroxide, in phosphate buffer pH 7.4, consuming the oxygen present in solution, what didn't occur with other β-dicarbonyl compounds (dimedon and acetoacetate), under the same conditions. It was also observed, in the absorption spectrum during the reaction course with PD and 3-MePD, that the native enzyme was transformed to HRP-III; moreover, the reaction produced reactive oxidant species (ROS), detected by luminol-dependent chemiluminescence and dichlorofluorescein-fluorescence dependent. Reactions of oxygen uptake with other heme-compounds (cytochrome C, hemin, myoglobin and myeloperoxidase) had been carried to detect the especificity of the HRP in the oxidation reaction... (Complete abstract click electronic access below)
Orientador: Iguatemy Lourenço Brunetti
Coorientador: Valdecir Farias Ximenes
Banca: Olga Maria mascarenhas de Faria Oliveira
Banca: Chung Man Chin
Banca: Antonio Cardozo dos Santos
Banca: Mariza Pires de Melo
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Martins, Diana Maria Serafim. "Desenvolvimento de eletrodos modificados para determinação de compostos sulfurados em gasolina /." Araraquara : [s.n.], 2008. http://hdl.handle.net/11449/105745.

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Orientador: Nelson Ramos Stradiotto
Banca: Maria Del Pilar Taboada Sotomayor
Banca: José Fernando de Andrade
Banca: Jeosadaque José de Sene
Banca: Adaléa Lopes Brandes Marques
Resumo: Os compostos sulfurados no petróleo têm causado diversos problemas como os correlacionados à corrosão de equipamentos, envenenamento de catalisadores em processo de refino, qualidade dos produtos, além de liberação de gases tóxicos diretamente ao meio ambiente. Os compostos sulfurados em especial (enxofre elementar, difenil dissulfeto e 1-butanotiol) podem agravar estes problemas, sendo os principais causadores de corrosão de equipamentos nas refinarias de petróleo. Devido a tais considerações, a proposição deste trabalho é o desenvolvimento de metodologias eletroanalíticas para determinação de compostos sulfurados em gasolina, utilizando os eletrodos de filme de mercúrio, amálgama sólido e hexacianoferrato de cobre. No primeiro trabalho desenvolvido utilizou-se o eletrodo filme de mercúrio juntamente com as técnicas eletroanalíticas de voltametria de varredura linear (VVL), onda quadrada (VOQ) e pulso diferencial (VPD) em solução de acetato de sódio 1,4 mol L-1 e ácido acético 2% em metanol, como eletrólito suporte. O método apresentou limites de detecção na ordem de 10-9 a 10-4 mol L-1 para as técnicas eletroanalíticas de VVL, VOQ e VPD, inferiores aos já relatados na literatura usando método análogo. A quantificação dos compostos de enxofre em amostras de gasolina, a partir do monitoramento do sinal de redução sobre a superfície do eletrodo filme de mercúrio, utilizando a técnica de voltametria de onda quadrada, foi possível sem tratamento prévio da amostra, cujo procedimento mostrou ser bastante eficiente não provocando qualquer interferência associada aos constituintes da matriz, exibindo valores de 3,5x10-8, 3,7x10-7 e 4,2x10-8 mol L-1 para enxofre elementar, difenil dissulfeto e 1-butanotiol, respectivamente. A quantificação nas amostras de gasolina, avaliadas em termos... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The presence of sulfur compounds in petroleum has caused several problems including those related to the corrosion of equipments, and the quality of final products, as well as the emission of toxic gases to the environment. Sulfur compounds (elemental sulfur, diphenyl disulfide and 1-butanethiol), can increase these problems, being the main causes of corrosion of equipments in the refineries of petroleum. Based on these assumptions, the principal proposal of this work is the development of electroanalytical methodology for determination of sulfur compounds in gasoline using the electrodes of mercury film, amalgam solid and copper hexacyanoferrate. In the first developed work the mercury film electrode was used together with the electroanalytical techniques of linear scan voltammetry (LSV), square wave voltammetry (SWV) and differential pulse voltammetry (DPV) in solution of 1.4 mol L-1 sodium acetate and acetic acid 2% in methanol. The method presented detection limits in the order from 10-9 to 10-4 mol L-1 for the electroanalytical techniques of LSV, SWV and DPV. These limits are inferior to the previous related in the literature using similar method. The quantification of the sulfur compounds in gasoline samples, starting from the monitoring of the reduction sign on the mercury film electrode surface using the technique of square wave voltammetry was possible without previous sample treatment, whose procedure showed to be efficient, it not provoking any interference associated to the sample, exhibiting values of 3.5x10-8, 3.7x10-7 and 4.2x10-8 mol L-1 for elemental sulfur, diphenyl disulfide and 1-butanethiol, respectively. The quantification in the samples of gasoline in recovery terms showed that the methodology electroanalytical supplied quite acceptable results with recovery levels and precision compatible to the found by other techniques. In a second... (Complete abstract click electronic access below)
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Garcia, Melina Paula Batista. "Estudo das variações elétricas em filmes ultrafinos compondo as unidades sensoriais de uma "língua eletrônica" /." Presidente Prudente, 2008. http://hdl.handle.net/11449/88479.

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Orientador: Antonio Riul Júnior
Banca: Carlos José Leopoldo Constantino
Banca: Nilson Cristino da Cruz
O Programa de Pós-Graduação em Ciência e Tecnologia de Materiais, PosMat, tem caráter institucional e integra as atividades de pesquisa em materiais de diversos campi da Unesp
Resumo: Neste trabalho pesquisamos variações das propriedades elétricas de filmes ultrafinos de diferentes materiais, utilizados como unidades sensoriais de uma "língua eletrônica", simulando os resultados obtidos em diferentes paladares com um modelo de circuito elétrico equivalente, visando uma melhor compreensão do mecanismo de transdução envolvido. Foram utilizados filmes ultrafinos de quitosana, ftalocianina, polipirrol e perileno, que serviram de elementos transdutores do dispositivo, similar às papilas gustativas na língua humana, pois a diferença de resposta entre eles pode ser utilizada como uma impressão digital dos líquidos analisados. Esses materiais foram depositados sobre lâminas de quartzo e eletrodos interdigitados através das técnicas Langmuir-Blodgett (LB), automontagem e evaporação a vácuo. Inicialmente o trabalho foi na fabricação de filmes ultrafinos para familiarização das técnicas e equipamentos de medidas. Pôde-se verificar boa adesão dos materiais depositados sobre os eletrodos interdigitados mesmo após excessivas lavagens em água Milli-Q, permitindo sua reutilização na "língua eletrônica". Os eletrodos cobertos com filmes ultrafinos foram imersos em soluções 1 mM e 1μM ácidas, salgadas, doces, amargas e umami utilizando medida de impedância elétria e um modelo de circuito elétrico equivalente já existente na literatura. Analisamos a sensibilidade de resposta a uma temperatura de aproximadamente '20 GRAUS', avaliando como os parâmetros envolvidos no circuito elétrico equivalente variam de acordo com o tipo de solução analisada, nas concentrações 1 mM e 1μM, e ainda como esses parâmetros são afetados em um mesmo material na presença de diferentes analitos. Os resultados obtidos foram também analisados pelo método estatístico de Análise de Componentes Principais (PCA, do inglês "Principal Component Analysis") e Espectroscopia Raman.
Abstract: In this work we study variations in the electrical properties of ultra-thin films of different materials, used as individual sensing units in an "electronic tongue", simulating the results obtained in distinct tastants with an equivalent electric circuit, envisaging a better comprehension of the transducing mechanism involved. Ultra-thin films of chitosan, copper phtalocyanine, polypyrrole and perylene were used as transducers in the device, similar to the gustative papilae in the human tongue, as their electrical differences can be used as a fingerprint of the liquids analysed. The materials were deposited onto quartz plates and interdigitated electrodes through Langmuir-Blodgett (LB), layer-by-layer and vacuum evaporation techniques. Initially, we start the fabrication of the ultra-thin films to a better familiarization with equipments and tecniques. There was a good adhesion of the deposited films onto the interdigitated electrodes, even after excessive washings in Milli-Q water, allowing the re-use of the "eletronic tongue" system. The electrodes covered with ultra-thin films were have been soaked in 1mM and 1μM solutions of acidic, sweet, sour and bitter substances, using impedance spectroscopy as the measured technique and an equivalent circuit model already existent in the literature. The sensitivity of response at '20 GRAUS' was evaluated investigating seeking of how the involved parameters in the equivalent electric circuit varied according to the sort of solution analysed at mM and μM concentrations, and how they are affected by each material due to the presence of distinct analytes. The obtained results were also analysed by Principal Component Analysis and Raman Spectroscopy.
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Silva, Domingos Jorge Ferreira da. "Estudo dos efeitos do nitrato de lítio na expansão de argamassas sujeitas a reação álcali-sílica /." Ilha Solteira : [s.n.], 2007. http://hdl.handle.net/11449/91469.

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Resumo: Várias pesquisas realizadas com compostos a base de lítio tem mostrado resultados satisfatórios na redução da expansão associada à reação álcali-sílica (RAS), mas ainda existem muitas dúvidas sobre seus mecanismos de ação. A presente pesquisa avaliou os efeitos de uma adição química a base de nitrato de lítio (LiNO3) na redução da expansão associada a RAS, utilizando várias dosagens. Os estudo dos efeitos do LiNO3 na RAS foi feito pelo método acelerado das barras de argamassa (ASTM C-1260) utilizando dois tipos de agregado reativo. Também foram realizados ensaios de expansão com uma adição mineral a base de cinza volante a fim de correlacionar os efeitos de uma adição mineral com uma química na redução da expansão devido a RAS. Ensaios de resistência à compressão e trabalhabilidade foram realizados também buscando algum efeito do LiNO3 nestas propriedades. Os resultados do ensaio ASTM C-1260 indicaram que as adições de lítio foram efetivas na redução da expansão para os dois tipos de agregados reativos, sendo que para as condições e materiais utilizados na presente pesquisa foi necessário uma de adição de LiNO3 com relação molar (Li2O/Na2Oeq) de 7,00 para reduzir a expansão ao valor aceitável pela norma de 0,10% aos 16 dias. Foi observado também intensidades de redução da expansão diferentes entre os dois tipos de agregados estudados devido a diferença de reatividade dos mesmos. Verificou-se um limite de adição de lítio para o basalto, onde não havia mais redução significativa de expansão com o aumento da dosagem de adição. Observou-se também que as misturas contendo LiNO3 reduziram a expansão ao longo dos 30 dias, enquanto nas misturas contendo FA a expansão continuou a aumentar ao longo do teste. Os ensaios de condição de trabalhabilidade e de resistência à compressão mostraram que o LiNO3 não afeta consideravelmente estas propriedades.
Abstract: Lithium compounds have been shown satisfactory results for the reduction of the expansion due to alkali-silica reaction (ASR), but there are many doubts about its mechanisms of action. The present research evaluated the effects of a chemical addition to lithium nitrate based (LiNO3) on the reduction of expansion associated with ASR, utilizing several dosages. For the study of the effects of the LiNO3 on the ASR it was used the accelerated mortar bar method (ASTM C-1260), with two kinds of reactivate aggregate. Mortar bars were molded also with a mineral addition of fly ash based (FA) with the objective to compare the effects of a mineral addition with a chemistry on the expansion due ASR. Compressive strength and consistence index tests had been carried also for searching some effects of the LiNO3 at these properties. The results from ASTM C-1260 showed that the addition of LiNO3 were effective on the expansion reduction for two kinds of reactive aggregate, which current conditions and materials on this research required a LiNO3 addition with (Li/Naeq) of 7,00 molar ratio to decrease the expansion to an acceptable value of 0,10% on 16 days. Also, the intensity of the expansion reduction was observed between two kinds of studied aggregates by their reactivity difference. A lithium additive upper bound was verified for the basalt, where it did not have more significant reduction of expansion with the increase of the dosage of addition. Also, was observed that admixtures that contained LiNO3 have reduced the expansion trough 30 days, while on the admixtures that contained FA the expansion grew up. The results obtained for the compressive strength and consistence index tests showed no significant differences between mixtures with and without LiNO3 admixture.
Orientador: Jorge Luís Akasaki
Coorientador: Haroldo de Mayo Bernardes
Banca: Marco Antonio Morais Alcantara
Banca: Vladimir Antonio Paulon
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Moreira, Luiziane Albino Gonçalves. "Produtos nitrogenados na saliva de portadores de doença renal crônica em hemodiálise /." Araraquara : [s.n.], 2010. http://hdl.handle.net/11449/88624.

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Orientador: Júlio Sérgio Marchini
Banca: João Bosco Faria
Banca: Karina Pfrimer
Resumo: Na avaliação de pacientes portadores de doença renal crônica, além da análise da alimentação ingerida é importante a análise da presença de produtos nitrogenados nos fluidos corporais como o sangue e urina, apresentando para este fim como grande potencial, a análise da saliva. Nesse sentido, uma das áreas relacionadas com a análise de alterações da composição bioquímica da saliva e que vem despertando o interesse, é a evolução clínica de pacientes portadores de doença renal, submetidos ou não a tratamento dialítico. Com base no contexto acima, a presente pesquisa teve por objetivo avaliar a saliva como meio de monitorar as variações dos compostos nitrogenados, em portadores desta patologia submetidos ao tratamento dialítico. No desenvolvimento da pesquisa foram avaliados a ingestão alimentar, a antropometria e os seguintes indicadores bioquímicos e físico-químicos: uréia, proteína total, aminoácidos, pH, e fluxo salivar. Foram encontrados nas determinações de uréia realizadas no soro, saliva não estimulada e saliva estimulada 136 mg/dl,107 mg/dl e 97 mg/dl antes da hemodiálise, respectivamente; e após a mesma, 39 mg/dl, 38,9 mg/dl e 36,0 mg/dl. As proteínas totais no soro, na saliva não estimulada e saliva estimulada apresentaram respectivamente valores de 7,0 g/dl, 0,30 g/dl; e 0,19 g/dl antes da hemodiálise e após a mesma, 9,0 g/dl, 0,22 g/dl e 0,20 g/dl. O pH salivar sofreu decréscimo após a hemodiálise. Os resultados obtidos permitem concluir que as proteínas totais na saliva e no soro não apresentaram comportamento semelhante. A hemodiálise atua sobre o pH salivar, mas não restabelece os níveis normais. A hemodiálise foi efetiva em reduzir a concentração dos compostos nitrogenados presentes na saliva
Abstract: In the evaluation of patient carriers of chronic renal disease, besides the analysis of the ingested food, the analysis of the presence of nitrogenous products in the physical fluids like blood and urine and saliva are also important. In this sense, one of the areas of great scientific interest related to the analysis of biochemical composition alterations of saliva is the clinical evolution of patient carriers of renal disease, subjected or not to hemodialysis treatment. These studies can subsidize the development in the future of diagnoses methods for renal patients through the analysis of saliva. Based on the above context, this research aimed to evaluate saliva as a means of monitoring changes of nitrogen compounds in patients with renal disease undergoing dialysis. At the development of this research, food ingestion, the antropometria and the following biochemical and physical-chemical indicators were analyzed: urea, total protein, aminoacids, pH and salivary flow. The determinations of urea in the serum, of not stimulated saliva and of stimulated saliva were 136 mg/dl, 107 mg/dl and 97 mg/dl, respectively, before the hemodialysis, and after that, 39mg/dl, 38,9mg/dl and 36,0mg/dl. The total proteins in the serum, not stimulated saliva and stimulated saliva showed up 7,0 g/dl, 0,3 g/dl and 0,19 g/dl before the hemodialysis, respectively, and after that 9,0 g/dl, 0,22 g/dl and 0,20 g/dl. The saliva pH decreased after the hemodialysis. The obtained results allowed to conclude that the total proteins in the saliva and in the serum did not present similar behavior. The hemodialysis influences the salivary pH but does not restore it to normal levels. The hemodialysis was effective in the reduction of nitrogen compounds present in saliva
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Corniani, Natália 1984. "Relação entre estresse de radiação ultravioleta-b e óxido nítrico em plantas de eucalipto /." Botucatu : [s.n.], 2009. http://hdl.handle.net/11449/88514.

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Resumo: As espécies do gênero Eucalyptus apresentam notável capacidade de extração de água e nutrientes, assimilação fotossintética e crescimento, permitindo seu cultivo em ambientes considerados impróprios para muitas outras espécies. Além dos fatores ambientais atuando adversamente no desempenho das plantas, atualmente estas estão sujeitas aos efeitos das mudanças ambientais globais causadas pelas atividades antrópicas, tais como o aumento na incidência da radiação ultravioleta-B (RUV-B) em conseqüência da destruição da camada de ozônio. Estudos recentes têm mostrado que a RUV-B promove aumento no nível de espécies reativas de oxigênio (ERO), ocasionando estresse oxidativo nas plantas. Entretanto, as plantas apresentam um sistema de defesa contra o estresse oxidativo, constituído de enzimas antioxidantes, tais como superóxido dismutase (SOD, EC 1.15.1.1) e peroxidase (POD, EC 1.11.1.7), além de outros compostos, como antocianinas, carotenóides e compostos fenólicos, que impedem a formação de ERO ou eliminam as já existentes. Há algum tempo, tem sido verificada em plantas a presença de óxido nítrico (NO), radical livre endógeno que possui a capacidade de controlar o nível e a toxicidade das ERO. Portanto, o objetivo deste trabalho foi investigar o possível efeito citoprotetor do NO em plantas de eucalipto (Eucalyptus urograndis) expostas à RUV-B. Assim, foi realizado um primeiro experimento no qual plantas de eucalipto foram expostas à RUV-B em baixa (controle) e elevada incidência, com o intuito de verificar se a radiação promove estresse oxidativo nesta espécie. Foram realizadas coletas de lâminas foliares aos cinco, dez e quinze dias após o início da exposição à RUV-B para posterior determinação do nível de peroxidação lipídica. A exposição por 15 dias à RUV-B... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The species of the genus Eucalyptus present notable capacity to extract water and nutrients, photosynthetic assimilation and growth, allowing cultivation in ambient considered inappropriate for many other species. Besides the environmental factors acting adversely in the performance of the plants, nowadays they are subject to the effects of the global environmental changes caused by human activities, such as the increase in the incidence of the ultraviolet-B radiation (UV-B) in consequence of the ozone layer destruction. Recent studies show that UV- B radiation promotes increase in the level of reactive oxygen species (ROS), causing oxidative stress in plants. However, plants have a defence system against oxidative stress, constituted of antioxidant enzymes, such as, superoxide dismutase (SOD, EC 1.15.1.1), peroxidase (POD, EC 1.11.1.7), and others compounds, such as anthocyanins, carotenoids and phenolic compounds, that avoid ROS formation or eliminate the already existent. There has been long, it was noticed the presence of nitric oxide (NO) in plants, endogenous free radical able to control the ROS level and toxicity. Therefore, the aim of this work was to investigate the possible citoprotector effect of the NO in eucalyptus (Eucalyptus urograndis) plants subjected to UV-B radiation. So, a first experiment was setup in which plants of eucalyptus were subjected to radiation in low (control) and high incidence of UV-B, to verify if UV-B radiation promotes oxidative stress in this specie. Leaves were collected at five, ten and fifteen days after the beginning of exposure to UV-B for subsequent evaluation of the level of lipid peroxidation. Exposure for 15 days to RUV-B increased the lipoperoxide content in the eucalyptus... (Complete abstract click electronic access below)
Orientador: Ana Catarina Cataneo
Coorientadora: Inês Cechin
Banca: Leonardo Cesar Ferreira
Banca: Terezinha de Fátima Fumis
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Leite, Carla Andréa. "Influência das condições de cultivo e métodos de extração na produção de metabólitos antioxidantes por fungos isolados do litoral paulista /." Araraquara : [s.n.], 2010. http://hdl.handle.net/11449/88055.

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Resumo: Vários estudos indicam que os antioxidantes podem prevenir e/ou atenuar o dano oxidativo causado pelos radicais livres, os quais em excesso estão associados com várias doenças neurodegenerativas, como Alzheimer e Parkinson. Nos últimos anos houve um aumento na descoberta de antioxidantes naturais devido à possibilidade de produção em larga escala a um custo menor que a síntese química. Devido ao seu enorme potencial de exploração, os fungos derivados do ambiente marinho são considerados um dos mais importantes recursos para a obtenção de novos agentes terapêuticos, pois um grande número de metabólitos estruturalmente novos e biologicamente ativos tem sido relatado destes organismos. Estudos também mostraram que a quantidade e a diversidade dos metabólitos secundários produzidos pelos fungos podem variar de acordo com o método de extração aplicado e as condições de cultivo. Neste contexto, o objetivo deste estudo foi identificar taxonomicamente algumas espécies de fungos isolados das praias do Cabelo Gordo de Fora (São Sebastião/SP) e Balneário (Peruíbe/SP) e avaliar a influência do solvente, tempo de extração, temperatura de evaporação dos solventes, o meio de cultura (Meio Completo Marinho e Meio Sabouraud) e a fase de crescimento do fungo (exponencial e estacionária) para obtenção de compostos com atividade antioxidante e também analisar cromatograficamente os extratos obtidos. Os fungos estudados foram identificados como: Aspergillus niger, A. versicolor, Aureobasidium pullulans, Cladosporium, Exophiala sp; Madurella grisea, Penicillium sp, Rhizopus oryzae, Trichophyton tonsurans e Trichophyton terrestre. Utilizando análise estatística, os resultados obtidos mostraram que a atividade antioxidante foi significantemente influenciada pelos parâmetros estudados. Em todos os extratos, independente da espécie do fungo, a atividade antioxidante... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Various studies indicate that the antioxidants can prevent and/or attenuate the oxidative damage caused by free radicals, which in excess are associated with various neurodegenerative disorders like Alzheimer's and Parkinson's disease. In recent years, there had a growing interest in the discovery of natural antioxidants due to the possibility of largescale production at a lower cost than chemical synthesis. Marine-derived fungi, due to its enormous potential for exploration, have been considered one of the most important resources to obtain of new therapeutic agents because a large number of structurally novel and biologically active metabolites have been reported from these organisms. Studies also have shown that the quantity and diversity of secondary metabolites produced by fungi can vary depending on the applied extraction method and the cultivation conditions. In the context, the objectives of this study were to identify taxonomically some fungi isolated from two locations: Cabelo Gordo de Fora beach (São Sebastião -SP) and Balneário beach, (Peruíbe - SP) and to evaluate the influence of solvent, extraction time, evaporation temperature of the solvents, the culture media (Marine Complete Medium and Sabouraud Medium) and stage of fungal growth (exponential and stationary phases) for obtaining compounds with antioxidant activity and also to analyze chromatographically the extracts obtained. The fungi studied were identified as: Aspergillus niger, A. versicolor, Aureobasidium pullulans, Cladosporium, Exophiala sp; Madurella grisea, Penicillium sp, Rhizopus oryzae, Trichophyton tonsurans and Trichophyton terrestre. Using statistical analysis, the results obtained showed that the antioxidant activity was significantly influenced by parameters studied. In all extracts, independent of the fungal species, the antioxidant activity increased with the longer time of extraction... (Complete abstract click electronic access below)
Orientador: Sandra Regina Pombeiro Sponchiado
Coorientador: Eduardo Maffud Cilli
Banca: Angêla Regina Araújo
Banca: Jairo Kenupp Bastos
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Hassan, Mohamed S. A. "Egg protein interactions with phenolic compounds: effect on protein properties." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=117210.

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Interactions of egg proteins (ovalbumin, conalbumin, egg white proteins, and egg yolk proteins) with selected phenolic compounds (flavone, chrysin, quercetin, and rutin) in aqueous media were examined by electrophoresis and fluorescence spectrophotometry. SDS-PAGE and native-PAGE results showed variable changes on the electrophoretic behaviour of egg white proteins in the presence of quercetin, while conalbumin-phenolic reaction products showed interactions under non-reducing conditions only. Fluorescence quenching technique was used to investigate the nature of egg protein-phenolic interactions and to estimate the effect of glycosylation and hydroxylation of phenolic compounds on the affinity to egg proteins. Stern-Volmer data revealed that the mechanism of egg protein-phenolic interactions is the static quenching and suggest that the diffusion does not play a role in fluorescence quenching in egg protein-phenolic interactions; the binding data analysis suggests that glycosylation and hydroxylation of phenolic compounds lower the affinity to egg proteins. Fluorescence quenching results showed that fluorescence intensity of egg proteins decreased with increasing concentration of phenolics. Enzymatic hydrolysis of egg protein-phenolic products assessed by using trypsin-chymotrypsin mixture and bacterial protease revealed that in vitro egg protein digestion was adversely affected by the interaction of phenolics. Proteins extracted from muffin mixture with added phenolics were investigated by electrophoresis techniques and enzymatic hydrolysis. SDS-PAGE results showed changes in electrophoretic patterns of ovalbumin. In vitro enzymatic hydrolysis of proteins extracted from the muffin was adversely affected by the addition of phenolics.
Les interactions de protéines d'œuf (ovalbumine, conalbumine, protéines de blanc d'oeuf, protéines de jaune) avec des composés phénoliques sélectionnés (flavone, chrysine, quercétine et rutine) dans des milieux aqueux ont été examinées par électrophorèse et spectrofluorométrie. Les résultats de native-PAGE et SDS-PAGE ont montré des changements variables sur le comportement électrophorétique des protéines du blanc d'œuf en présence de la quercétine, tandis que les produits de réaction entre conalbumine et phénoliques ont montré des interactions dans des conditions non réductrices seulement. La technique extinction (quenching) de la fluorescence a été utilisé pour étudier la nature des interactions protéines d'oeuf et phénoliques, et pour estimer l'effet de la glycosylation et l'hydroxylation de composés phénoliques sur l'affinité à la protéine d'oeuf. Les données de Stern-Volmer ont révélé en utilisant un quencher « desactivateur » que le mécanisme d'interactions entre la protéine d'œuf et les composées phénoliques est de type électrostatique et suggère que la diffusion ne joue pas un rôle dans l'extinction de la fluorescence en présence d'interactions protéines d'œuf et composés phénoliques. L'analyse des données « binding » soit des liaisons, suggère que la glycosylation et l'hydroxylation des composés phénoliques réduit l'affinité pour les protéines d'oeuf. Les résultats de l'extinction de la fluorescence ont montré que l'intensité de fluorescence des protéines de l'œuf diminue avec l'augmentation de la concentration des composés phénoliques. Les produits d'hydrolyses enzymatiques des complexes protéines d'oeuf-composés phénoliques évaluées suite à une protéolyse par un mélange trypsine-chymotrypsine et de la protéase bactérienne ont révélé que la digestion in vitro des protéines d'oeuf a été affectée négativement par l'interaction des composés phénoliques. Les protéines extraites du mélange à muffins enrichis en composés phénoliques ont été étudiés par des techniques d'électrophorèse et d'hydrolyse enzymatique. Les résultats du SDS-PAGE ont montré des changements dans le modèle électrophorétique de l'ovalbumine. L'hydrolyse enzymatique in vitro des protéines extraites du muffin a été affectée négativement par l'ajout de composés phénoliques.

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Giocondo, Maísa Pasquotto. "Avaliação da atividade apoptótica de substância pura isolada de Cryptocarya mandioccanna em células de carcinoma cervical imortalizadas pelo papilomavirus humano (HPV) /." Araraquara : [s.n.], 2007. http://hdl.handle.net/11449/89140.

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Orientador: Christiane Pienna Soares
Banca: Cleslei Fernando Zanelli
Banca: Andreimar Martins Soares
Resumo: Diversos estudos buscam identificar compostos com atividade seletiva para celulas tumorais e que possuam mecanismo de acao para desencadear a apoptose. Dentre as substancias isoladas de Cryptocarya sp, algumas estirilpironas, como a goniotalamina, apresentam atividade antiproliferativa e apoptogenica em diferentes linhagens celulares. No presente estudo, foram avaliadas as atividades citotoxica e pro-apoptotica da estirilpirona (criptomoscatona D2) isolada de Cryptocarya mandioccana, em linhagens celulares de carcinoma cervical humano infectada por HPV (HeLa e SiHa), nao infectada (C33A) e fibroblasto pulmonar humano transformado pelo SV-40 (MRC-5). A atividade citotoxica foi avaliada pelo ensaio do MTT e a apoptose foi avaliada, respectivamente, pelos ensaios de anexina V e a expressao de bak/bcl-2, por citometria de fluxo. Para o ensaio do MTT, as celulas foram tratadas com estirilpirona (criptomoscatona D2) nas concentracoes de 15, 30, 60 e 90-ÊM por 6, 24 e 48 horas e por 6 horas com periodo de recuperacao de 24, 48 e 72 horas pos tratamento. Para os ensaios de apoptose, as celulas foram tratadas por 6 horas e periodo de recuperacao de 24, 48 e 72 horas. O tratamento com a estirilpirona (criptomoscatona D2) ocasionou elevada citotoxicidade dose-resposta e tempo-resposta em HeLa, SiHa, C33A e MRC-5. Embora nao haja diferenca estatisticamente significativa de citotoxicidade entre as linhagens, aparentemente a citotoxicidade foi maior em HeLa e C33A (tratamento de 24 e 48 horas) que em MRC-5 e SiHa. Ainda, no periodo de recuperacao, HeLa e SiHa aparentemente restabelecem sua capacidade proliferativa, que e diretamente proporcional ao tempo de recuperacao, enquanto o mesmo comportamento nao e observado em C33A. Ao avaliar a expressao de duas proteinas da via intrinseca de apoptose (bcl-2 e bak), nao foi observada modulacao dessa expressao entre as linhagens celulares, nas diferentes tempos de recuperação pos-tratamento.
Abstract: Several attempts have been made to identify chemical compounds with selective cytotoxicity against cancer cells and apoptosis trigger activity. Among the substances isolated from Cryptocarya sp, some styrylpyrones, such as goniothalamine, demonstrate antiproliferative and apoptotic activity in abroad human cell lines. In the present study, we evaluated the antiproliferative and apoptotic activities of the styrylpyrone (cryptomoschatone D2) isolated from Cryptocarya mandioccana in HPV-infected (HeLa and SiHa) and non-infected (C33A) human cervical carcinoma cell lines, and in human lung's fibroblast immortalized with SV-40 (MRC-5). The antiproliferative activity was evaluated by the MTT assay and the apoptotic activity was investigated by measuring the expression levels of annexin V and bak/bcl-2 by flow cytometry. In the MTT assay, cells were treated with styrylpyrone (cryptomoschatone D2) at a 15, 30, 60 or 90ìM concentration for 6, 24 or 48 hours as well as for 6 hours followed by a recovery posttreatment period of 24, 48 or 72 hours. In the apoptotic assays, cells were treated for 6 hours followed by a recovery posttreatment period of 24, 48 or 72 hours. High cytotoxicity (dose-response and time-response) was observed in HeLa, SiHa, C33A and MRC-5 cell lines. Although the styrylpyrone cytotoxicity was not significantly different among the cell lines tested, the citotoxicity was apparently higher in HeLa and C33A than MRC-5 and SiHa in the case of treatments for 24 or 48 hours. Moreover, HeLa and SiHa were able to recover their prolifetative status, which were directly proportional to the posttreatment recovery time. On the other hand, C33A did not demonstrate a similar posttreatment recovery. Despite the posttreatment recovery time, the expression of the apoptotic proteins bcl-2 and bak seems not to be modulated by the treatment.
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16

Taljaard, Marelie. "Isolation and identification of the toxic compounds of Tapura fischeri Engl." Diss., University of Pretoria, 2014. http://hdl.handle.net/2263/46062.

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Tapura fischeri is a member of the family Dichapetalaceae and the only other member of this family naturally occurring in South Africa is Dichapetalum cymosum. Poisoning by D. cymosum results in the deaths of many domestic livestock each year due to the presence of fluoroacetate. The aim of the study was to determine if monofluoroacetate or another fluorinated compound is present in T. fischeri, and the possible role endophytes might play in the production of these compounds. Through NMR and GCMS studies it was established that trifluoroacetate is present in T. fischeri. Bacterial endophytes were isolated from plant material and shown to produce a fluorinated compound other than mono and trifluoroacetate. Since trifluoroacetic acid is extremely volatile, and evaporate from the plant extract over time, column chromatography, together with NMR was employed to isolate and identify other compounds responsible for antibacterial activity against the bacterium Enterococcus faecalis previously observed on TLC plates. Two compounds were isolated, and identified with NMR as a fatty acid and a fatty acid attached to glycerol. The names of the compounds could not be established with GCMS due to insufficient derivatization of the compounds. The antibacterial activity of the compounds were also analyzed using 96 well microtitre plates in liquid media, where it was determined that the compounds do not have antibacterial activity against E. faecalis. This indicated that previous results on TLC plates were false positives due to the hydrophobic nature of the fatty acid compounds. Transmission electron microscopy was done on leaf material to determine the presence of bacterial endophytes in the intracellular spaces of plant material, but none was detected. These results suggest a possitive correlation between the plant, its endophytes and the production of the fluorinated compound.
Dissertation (MSc)--University of Pretoria, 2014.
tm2015
Plant Science
MSc
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17

Souza, Gledison Rogerio de. "Estudo termoanalítico e eletroquímico das reações em estado sólido na interfase metálica dos sistemas Pt-Rh/Hg, empregando a liga de composição Pt-Rh 80:20% (m/m) /." Araraquara : [s.n.], 2004. http://hdl.handle.net/11449/97743.

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Orientador: Fernando Luis Fertonani
Resumo: Neste trabalho voltametria cíclica, análise térmica (TG/DTG), e análise de superfície (Microanálise por EDX, mapeamento dos elementos, obtenção das imagens SEM e XRD), foram utilizadas para o estudo das reações em estado sólido entre a liga de composição Pt-Rh 80:20%(m/m) e o Hg. A partir das técnicas de voltametria cíclica e termogravimetria-termogravimetria derivada (TG/DTG), foi possível evidenciar o ataque efetivo do Hg sobre o substrato, e ainda, a formação de compostos de caráter covalente, do tipo: PtHg, PtHg2, RhHg2 e PtHg4, caracterizados através da técnica de difratometria de Raios X (XRD). As análises de superfície, permitiram revelar, a presença de um filme de intermetálicos sobre a superfície do substrato, e uma distribuição homogênea do Hg sobre a superfície do substrato. O sistema Pt-Rh 80:20%(m/m)-Hg apresentou um comportamento térmico (TG) e eletroquímico (VC), similar ao sistema Pt-Rh 85:15%(m/m)-Hg, e também apresentou um ataque considerável ao substrato quando comparado à liga de Pt-Rh 70:30%, esta, por sua vez, não apresenta a formação do intermetálico PtHg4. Desta forma, o comportamento observado para o sistema Pt-Rh 80:20% (m/m)- Hg, apresenta reatividade intermediária aos sistemas Pt-Rh 85:15%(m/m)-Hg e Pt- Rh 70:30%(m/m)-Hg, devido ao teor do elemento modificador, Rh, na matriz de Pt, como o esperado.
Abstract: In this work, ciclic voltametry, thermal analysis (TG/DTG), and analysis of surface (EDX Microanalysis, Mapping, and XRD), were utilized for the study of the reactions in solid state between the Pt-Rh 80:20% alloy and the Hg. The CV and TG showed an effective Hg attack on the alloy, and the formation of covalent compounds such as PtHg, PtHg2, RhHg2 and PtHg4, characterized by XRD technique. From the techniques of ciclic voltametry and termogravimetry-derived termogravimetry (TG/DTG), was possible show up an effective Hg attack on the alloy, and the covalent compounds formation as PtHg, PtHg2, RhHg2 and PtHg4, characterized by X-Rays Difratometry (XRD). The surface analysis showed an intermetallic film on the alloy surface, and the Hg homogeneous distribution on the surface. The Pt-Rh 80:20%(m/m)-Hg system presented an eletrochemical (VC) and thermal behavior (TG), similar to Pt-Rh 85:15%(m/m)-Hg system, and presented also a considerable Hg attack to the alloy when compared to the Pt-Rh 70:30% alloy, this system, doesn't present the intermetallic PtHg4 formation. In this way, the behavior observed for the system Pt-Rh 80:20% (m/m)-Hg, presents an intermediate reactivity to the systems Pt-Rh 85:15%(m/m)-Hg and Pt-Rh 70:30%(m/m)-Hg, due to the content of the modificator element, Rh, in the matrix of Pt, as him expected. Keywords: intermetallic compounds; platinum; rhodium; mercury.
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18

Nascimento, Noelle Mariane do. "Polimorfismo nos complexos de trietanolamina dos metais do quarto período /." Araraquara [s.n.], 2012. http://hdl.handle.net/11449/97914.

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Resumo: Devido a contradições presentes na literatura quanto à natureza dos complexos dos metais do quarto período da tabela periódica com o ligante tris(2-hidroxietil)amina (trietanolamina) (TEAH3), uma reinvestigação foi feita consistindo na exploração das possibilidades do ligante em formar dímeros ou até polímeros com a propriedade de polimorfismo com sais dos metais de transição Co2+ e Cu2+. Com o metal representativo Zn2+, os compostos não apresentaram a propriedade de se cristalizarem em mais de uma estrutura cristalográfica distinta. Os complexos [MCl(TEAH2)] foram preparados a partir de misturas de soluções de MCl2 e TEAH3 em várias proporções, e os produtos foram caracterizados pela espectroscopia no infravermelho e difratometria de raios-X (em pó e em monocristal). Durante as tentativas de obtenção de monocristais dos complexos [MCl(TEAH2)] (M=Co, Cu, Zn) em álcool isoamílico, observou-se a oxidação inusitada do ligante TEAH2 coordenado, obtendo-se derivados de fórmula geral [M(bic)2] (M=Co, Cu, Zn). A determinação da estrutura molecular e cristalina do monocristal de [Cu(bic)2] obtido foi realizado pelo Prof. Dr. Carlos B. Pinheiro, da Universidade Federal de Minas Gerais (UFMG)
Abstract: Due to contradictions in the literature as to the nature of the complexes of metals of the fourth period of the periodic table with the ligand tris(2- hydroxyethyl) amine (triethanolamine) (TEAH3), a reinvestigation was made consisting in exploring the possibilities of the ligand to form dimers or even polymers with the property of polymorphism with salts of transition metals Co2+ and Cu2+. With the metal representative Zn2+, the compounds did not show the property to crystallize in more than one different crystal structure. The complexs [MCl(TEAH2)] were prepared from mixtures of solution of MCl2 and TEAH3 in various proportions, and the products were characterized by infrared spectroscopy and X-ray diffraction (powder and single crystal). During attempts to obtain crystals of the complexes [MCl(TEAH2)] (M = Co, Cu, Zn) in isoamyl alcohol, was observed unusual oxidation of TEAH2 coordinated that yield derivatives of formula [M(bic)2] (M = Co, Cu, Zn). The determination of crystal and molecular structure of the single crystal of [Cu(bic)2] obtained was carried out by Professor. Dr. Carlos B. Pinheiro, Universidade Federal de Minas Gerais (UFMG)
Orientador: Adelino Vieira de Godoy Netto
Coorientador: Stanlei Ivair Klein
Banca: Alexandre de Oliveira Legendre
Banca: Vinicius Caliman
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19

Poppi, Nilva Ré. "Hidrocarbonetos policíclicos aromáticos e outras substâncias orgânicas na combustão de madeira para produção de carvão e em particulado atmosférico da cidade de Campo Grande /MS /." Araraquara : [s.n.], 2000. http://hdl.handle.net/11449/105763.

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Orientador: Mary Rosa Rodrigues de Marchi Santiago da Silva
Banca: Lilian Rotschild de Carvalho
Banca: Fernando Mauro Lanças
Banca: Maria Lucia Ribeiro
Banca: Alberto José Cavalheiro
Resumo: município de Campo Grande, MS, com uma população de aproximadamente 600 mil habitantes concentrados na área urbana, todos os anos, entre os meses de julho a novembro, período muito seco, fica encoberto pela fumaça proveniente da queima de biomassa, a qual tem sido apontada como responsável pelo aumento da incidência de casos de doenças respiratórias na população. Neste trabalho, é reportada a composição química de aerossóis, partículas inaláveis (1 μm ≤ dp≤ 15 μm), de emissões do forno utilizado para a produção de carvão vegetal e de 14 amostras de ar da cidade de Campo Grande / MS. O particulado atmosférico foi amostrado de junho a novembro de 1998 no campus da UFMS e as amostras de emissão direta foram coletadas a 1,5 m de um forno construído com tijolos e saibro, similar aos utilizados nas carvoarias da região. Nos dois tipos de amostra, o material particulado foi coletado sobre filtro de Fluorepore em PTFE com 37 mm de diâmetro e as substâncias semivoláteis em tubos do adsorvente XAD-2, utilizando-se amostrador de baixo volume (low-vol). As substâncias foram extraídas com diclorometano/metanol (4:1) em banho ultra-sônico. As análises foram realizadas por CG/EM nos modos SCAN e SIM. A concentração de HPAs na atmosfera próxima ao forno, proveniente da queima de madeira para produção de carvão, foi estimada em 23,6 μg.m-3 de ar para a soma de 15 HPAs, e em 310,1 ng.m-3 para o BaP. A concentração média dos 15 HPAs nas amostras ambientais foi de 21,05 ng.m-3 e a concentração média do BaP de 0,25 ng.m-3...(Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Campo Grande City (Mato Grosso do Sul State, Brazil) has around 600,000 inhabitants, concentrated in the urban area. Every year, between July and November, the dry season, the city is covered with biomass burning smoke. The biomass burning is result of the vegetal carbon production, agricultural handling, or de-florestation operation into Brazilian Savannah ("cerrado"). The smoke has been indicated as main cause of respiratory disease increasing of the population. In this work it was reported the aerosol composition (1μm ≤ dp≤ 10 μm), from emission of vegetal carbon production and 14 air samples of Campo Grande city. The particulate material was sampled from June until November, 1998 at campus of Federal University of Mato Grosso do Sul (UFMS) while the emission samples were collected at 1.5 m far from an oven made with brick and a mixture of clay and sand, similar to ones used by vegetal carbon producers of region. For both kind of samples, the particulate material was collected with Fuorepore/PTFE filters (37 mm diameter) while volatile fraction was sampled into adsorbent tubes (XAD-2), using low vol sampler. The extracts were obtained by ultrasonic bath using dichloromethane:methanol (4:1) and were analyzed by GC/MS, SCAn and SIM modes. The total HPAs emission of vegetal carbon oven was estimated in 23.6 μg.m-3 and 310 ng.m-3 for benzo(a)pyrene. On the other hand, the city air samples shown concentration (average) of 21,05 ng.m-3 for total HPAs, and 0.25 ng.m-3 for benzo(a) pyrene. HPAs, OXI-HPAs, phenols e Metoxy-phenols were identified...(Complete abstract, click electronic access below)
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20

Eberlin, Ludovic. "Novel applications of polyfunctionalised organoboron and nitroso compounds." Thesis, Rennes 1, 2016. http://www.theses.fr/2016REN1S078/document.

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Cette thèse présente la réactivité de diènes polyfonctionnalisés incorporant un atome de bore (diènes borylés) en présence de composés de type nitroso. La première partie est une étude de la réactivité des diènes borylés en présence de dérivés arylnitroso. Le produit formé ainsi que l'efficacité de la réaction est dépendant de la substitution sur l'atome de bore ainsi que du solvant utilisé pour la réaction. Suivant les conditions employées, la formation de composés avec différentes structures; pyrroles, oxazines substitués par un atome de bore, ou nitrones a été obtenue. Une stratégie one-pot a ensuite été développée pour la synthèse d'oxazolines utilisant la formation des nitrones en tant qu'intermédiaire. Des investigations théoriques et pratiques concernant le mécanisme de la formation du pyrrole ont été réalisées. La séquence expliquant la synthèse de cette structure est basée sur la cascade suivante; cycloaddition régiosélective (Nitroso Diels-Alder)/réarrangement/élimination du borate. La formation des composés de type nitrone n'a pas été totalement explicité. Des recherches sont actuellement en cours dans le but d'obtenir plus de détails sur le mécanisme mis en jeu. La deuxième partie de l'étude est orientée sur la réactivité des diènes borylés en présence de dérivés carbonylnitroso. Au contraire des dérivés arylnitroso, la nature du composé carbonylnitroso joue un rôle majeur sur la réactivité. Si le même type de réactivité engendrant la formation de pyrroles et d'oxazines substitués par un atome de bore a été observé dans certains cas, l'utilisation d'un composé carbonylnitroso étant assez pauvre en électrons génère la formation du produit issu d'une réaction nitroso-ène. Ce produit, issu de la réaction nitrosoène, a été utilisé comme intermédiaire clé pour la synthèse de différents produits polycycliques. Une séquence one-pot, multicomposants, Diels-Alder/allylboration a été optimisée donnant différentes structures suivant le dienophile et l'aldehyde employé. Dans le but de diversifier la chimie du produit résultant de la réaction nitroso-ène, une autre séquence a été mise au point utilisant la synthèse des pyrroles. Une voie multi-étape a permis la synthèse de nouvelles structures bicycliques incorporant une oxazine et un pyrrole
This thesis presents the reactivity of dienylboronated compounds towards arylnitroso and carbonylnitroso derivatives and its use in the synthesis of heterocyclic and polycyclics compounds. The first study focused on the reactivity of dienylboronate compounds with arylnitroso derivatives resulting in pyrrole or furan products. The outcome and efficiency of the reaction is related to the boron on the dienyl moiety and the solvent used. Using the certain conditions, pyrroles, boronated MIDA ester oxazines or nitrones could be obtained. A one-pot strategy was then applied to synthesise oxazoline derivatives using nitrones as an intermediate. Theoretical, as well as experimental, work has supported that the formation of the pyrrole was obtained by a regioselective nitroso Diels-Alder reaction/rearrangement/borate elimination cascade process. Details on the nitrone formation have not been clarified, but further investigations are on-going. Secondly, attention was focused on the reactivity of dienylboronate compounds with carbonylnitroso derivatives. Contrary to the arylnitroso species, the nature of the carbonylnitroso had a dramatic impact on reactivity. On the one hand, similar reactivity towards the formation of pyrroles and boronated MIDA ester oxazines was observed, however, by employing a higher electron-deficient carbonylnitroso species, the product resulting from a nitroso-ene reaction was obtained. Ene-product was used as the key intermediate for the synthesis of different polycyclic compounds. A multicomponent, one-pot, Diels-Alder/allylboration procedure was optimised to yield various structures depending on the nature of the dienophile and the aldehyde. To diversify the chemistry of the ene-product another sequence was designed using the pyrrole synthesis. A multi-step pathway was optimised to afford novel fused bicylic oxazine-pyrrole products

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21

Scachetti, Tatiane Pereira. "Estudo das reações de oxidação de etileno glicol e glicerol sobre nanopartículas intermetálicas de PtSb/C e PdSb/C /." Bauru : [s.n.], 2012. http://hdl.handle.net/11449/106645.

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Orientador: Antonio Carlos Dias Ângelo
Banca: Luiz Henrique Dall'Antonia
Banca: Hamilton Brandão Varela de Albuquerque
Banca: Germano Tremiliosi Filho
Banca: Fenelon Martinho Lima Pontes
O Programa de Pós Graduação em Ciência e Tecnologia de Materiais, PosMat, tem caracter institucional e integra as atividades de pesquisa em materiais de diversos campi
Resumo: No presente trabalho foram estudadas as reações de oxidação de etileno glicol e glicerol sobre a superfície dos intermetálicos PtSb/C e PdSb/C, em meio alcalino (NaOH) e ácido (HCIO4). As nanopartículas intermetálicas de PtSb/C e PdSb/C foram preparadas pelo método de redução de poliol e caracterizadas por DRX, MEV-EDX e MET, cujos resultados indicaram que a metodologia utilizada foi eficaz para a obtenção dos materiais na estequiometria desejada. A análise morfológica da superfície dos intermetálicos mostrou a formação de aglomerados e tamanho médio de partículas entre 1nm e 2nm, para o material PdSb/C e PtSb/C, respectivamente. A eletrocatálise das reações de oxidação dos alcóois foi avaliada por voltametria cíclica e cronoamperometria, em temperatura ambiente. Os resultados revelaram que o material PtSb/C apresenta maior desempenho eletroquímico que a Pt/C E-TEK na oxidação do glicerol em meio alcalino. O intermetálico PdSb/C não apresenta atividade eletroquímica em meio ácido. Contudo, em meio alcalino, o PdSB/C exibe maior tolerância ao bloqueio de intermediários adsorvidos do que a superfície da Pt/C E-TEK, e desloca o potencial de início de oxidação do glicerol para valores mais negativos, em relação ao Pd/C. Por meio de experimentos de espectroscopia de infravermelho in situ foram propostas rotas reacionais para as oxidações investigativas. A formação de CO2 em ácido, e carbonato em meio alcalino, foi observada para a superfície do PtSb/C na oxidação de ambos os alcóois, indicando que a clivagem da ligação C-C é efetiva sobre a superfície deste material. Contudo, o ácido glicólico é o principal produto formado durante a oxidação do etileno glicol, em meio ácido e alcalino, sobre a superfície do PtSb/C; e também na oxidação de ambos os alcoóis, sobre o eletrodo intermetálico... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: In this work, the oxidation reaction of ethylene glycol and glycerol on the surface of the intermetallics PtSb/C and PdSb/C electrodes were investigated in both alkaline (NaOH) and acid (HCIO4) media. The intermetallics PdSb/C and PtSb/C nanoparticles were prepared via the polyol reduction method, and the resulting nanoparticles were characterized by XRD, SEM-EDS, and TEM techniques. The characterization data have indicated that the employed methodology indeed furnished materials with the desidered chemical identity stoichiometry. Surface morphology analysis revealed the presence of particles with mean sizes of 1 nm and 2 nm for PdSb/C and PtSb/C, respectively, as well as the formation of agglomerates. Oxidation reactions of the investigated alcohols were studied by cyclic voltammetry and chronoamperometry at room temperature. The obtained results have demonstrated that the PtSb/C electrode performed better than Pt/C E-TEK for glycerol oxidation in alkaline medium. The intermetallic PdSb/C electrode did not display any electrochemical activity in acidic medium. However, in alkaline medium, the PdSb/C electrode exhibited higher tolerance to active site blockage as compared to the Pt/C R-TEK electrode surface. Moreover, the PdSb/C electrode shifted the onset of glycerol oxidation to less positive potential values as compared to Pd/C. In situ infrared spectroscopy experiments aided the proposal of reaction pathways for the studied oxidation reactions. The formation of Co2, in acidic medium, and carbonate, in alkaline medium, were detected for the reaction taking place on the surface of the PtSb/C electrode for the oxidation of both alcohols, showing that the C-C bond cleavage effectivelly took place on the surface of this material. Nevertheless, glycolic acid was the main product from ethylene glycol... (Complete abstract click electronic access below)
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22

Soriano, Junior Roberto. "Avaliação da presença de vapores no solo em antiga área industrial contaminada por hidrocarbonetos : concentrações medidas e simuladas /." Rio Claro : [s.n.], 2009. http://hdl.handle.net/11449/92755.

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Orientador: José Eduardo Zaine
Banca: Scandar Gasperazzo Ignatius
Banca: Fábio Augusto Gomes Vieira Reis
Resumo: A contaminação de solos e água subterrânea por hidrocarbonetos derivados de petróleo tende a liberar vapores que migram da subsuperfície para o ar, expondo, principalmente o ser humano à inalação de compostos que podem oferecer risco a sua saúde. Porém a volatilização destes compostos pode indicar as possíveis fontes de contaminação em subsuperfície. As agências de proteção ambiental, como a EPA (Environmental Protection Agency), nos Estados Unidos, e os órgãos ambientais no Brasil, como a CETESB - Companhia de Tecnologia de Saneamento Ambiental, tem recomendado a avaliação dos Compostos Orgânicos Voláteis - VOC, por meio da técnica denominada Soil Gas Survey. Esta técnica vem sendo largamente utilizada por empresas de consultoria ambiental. Consiste na verificação de concentrações anômalas de VOC no solo in-situ, por meio de analisadores portáteis como FID, PID e Oxidação Catalítica, balizando os trabalhos de investigação e direcionando a quantidade de sondagens e poços de monitoramento para coletas de amostras de solo e água subterrânea para análises químicas. Desta forma o presente trabalho avaliou a presença de possíveis vapores em uma antiga área industrial abandonada contaminada por BTEX e Organoclorados. Esta avaliação foi feita por meio da técnica Soil Gas Survey com a utilização do analisador portátil de Oxidação Catalítica e simulou a volatilização dos contaminantes presentes na água subterrânea por meio do modelo matemático RBCA - Risk- Based Corrective Action Tool Kit Version 2. Os baixos resultados da modelagem da volatilização dos compostos confirmaram os resultados nulos na campanha de avaliação dos VOC no solo pela técnica Soil Gas Survey. Estes resultados sugerem à não capacidade destes compostos chegarem até a superfície.
Abstract: The contamination of soils and underground water by hydrocarbonates of petroleum derivatives tend to release vapors that migrate from the subsurface to the air, exposing, mainly the human being to the inhalation of compounds that can offer risk to their health. However this volatilization of this compounds can indicate possible sources of contamination in the subsurface. The agencies of environmental protection, like the EPA (Environmental Protection Agency), in the United States, and the environmental organizations in Brazil, like CETESB - Company of Technology of Environmental Sanitation, has recommended the evaluation of Volatile Organic Compounds - VOC, through the technique called Soil Gas Survey. This technique has been largely used by companies of environmental consulting. It consists on the verification of VOC anomalous concentration in the soil in-situ, by portable analyzers like FID, PID and Catalytic Oxidation, beaconing the investigation work directing the quantity of polls and monitoring wells to the collection of samples of soil and underground water to chemical analyses. This way the present work evaluated the presence of possible vapors in an old abandoned industrial area contaminated by BTEX and organochlorines. This evaluation was made through the Soil Gas Survey technique with the use of the portable analyzer of Catalytic Oxidation and simulated the volatilization of the contaminants presented in the underground water through the mathematical model RBCA - Risk- Based Corrective Action Tool Kit Version 2. The low results of the simulation of the compounds volatilization confirmed the null results in the evaluation campaign of the VOC in the soil through the technique Soil Gas Survey. This results suggest the non capacity of this compound reaching the surface
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23

Zuanaze, Rita de Cássia Collicchio. "Perfil hematológico, bioquímico, histopatológico e toxicológico de gatos induzidos experimentalmente com monofluoroacetato de sódio /." Botucatu : [s.n.], 2006. http://hdl.handle.net/11449/101302.

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Orientador: Michiko Sakate
Banca: Noeme Sousa Rocha
Banca: Manoel Lima de Menezes
Banca: Mara Regina Stipp Balarin
Banca: Silvana Lima Gorniak
Resumo: O monofluoroacetato de sodio (MFAS) ou composto 1080 e um rodenticida que foi amplamente utilizado para o controle de roedores e predadores domesticos, apos sua descoberta em 1945. Este potente rodenticida age bloqueando o ciclo de Krebs por acao do seu metabolito toxico, o fluorocitrato, e como consequencia, inibe a resposta celular e a producao de ATP. O MFAS foi proibido por lei no Brasil e em diversos paises, mas seu uso indiscriminado continua causando diversos casos de intoxicacoes potencialmente fatais no homem e animais domesticos, principalmente em caes e gatos, representadas por alteracoes neurologicas e cardiacas. Pretendeu-se com este estudo caracterizar o perfil hematologico e bioquimico, as alteracoes histopatologicas e toxicologicas de gatos intoxicados experimentalmente com MFAS, com o objetivo de determinar metodos diagnosticos eficazes. Para tanto, foram utilizadas amostras de sangue de 16 gatos intoxicados experimentalmente com 0,45mg/kg de MFAS, por via oral. Estas amostras foram colhidas por puncao jugular e analisadas quanto ao perfil hematologico, bioquimica serica e analises toxicologicas em cromatografia liquida de alta eficiencia (CLAE), para deteccao e quantificacao do MFAS no soro dos animais. Avaliaram-se tambem as lesoes macro e microscopicas dos animais intoxicados que vieram a obito. Observaram-se leucopenia e trombocitopenia transitorias; hiperglicemia, aumento das enzimas musculares creatinoquinase (CK) e creatinoquinase fracao cardiaca (CK-MB); observaram-se tambem hipocalemia, hipofosfatemia e hipomagnesemia. Os achados macroscopicos e histopatologicos demonstraram lesoes caracteristicas de processos isquemicos e as analises toxicologicas demonstraram um metodo diagnostico simples e eficiente...(Resumo completo, clicar acesso eletrõnico abaixo)
Abstract: Sodium monofluoroacetate (SMFAC) or 1080 compound is a potent rodenticide, largely used since 1945 for rodent and domestic pest control. The toxic effects of SMFAC are caused by fluorocitrato, a toxic metabolite, which has a competitive action with aconitase enzyme, leading to citrate accumulation and interferes in energy production by Krebs cycle blockade. In Brazil, although prohibited by law, there is illegal use, keep causing intoxication in children and domestic animals, specially dogs and cats. The most common intoxication clinical signs are from the cardiac and neurological alterations. In the present study, 16 domestic cats were intoxicated with oral doses of monofluoroacetate (0.45mg/kg). The hematologic and biochemical profiles, and histophatological and blood serum toxicological analysis by high performance liquid chromatography (HPLC) were made to looking for a efficient diagnosis methods. The hematologic profile showed transitory leucopenia and trombocitopenia; the biochemical profile presented hiperglycemia, increase of creatinoquinase enzyme (CK) and creatinoquinase cardiac fraction (CK-MB), hypokalemia and hypophosfatemia were observed. The macrocospic and histopathological findings showed lesions characteristic of degenerative and ischemic processes. The toxicological analysis was shown to be a simple and efficient diagnostic method. SMFAC was detected in 75% of the serum samples analysed, and it was verified an average concentration of 0.32 ìg/mL in them; 4.81% of the serum samples did not show metabolized SMFAC six hours after the induced intoxication of the animals used in this study.
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24

Rodrigues, Carolina Munari. "Análise da resistência a cobre e zinco sobre o crescimento e expressão gênica em Xylella fastidiosa em condições de biofilme /." Botucatu : [s.n.], 2007. http://hdl.handle.net/11449/92465.

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Resumo: Baseado nas informações geradas após o seqüenciamento do genoma, foi desenvolvido uma série de meios de cultura de composição definida (XDM1, XDM2, XDM3, XDM4 e XDM5). Portanto, um dos objetivos do presente trabalho foi estabelecer a curva de crescimento da X. fastidiosa no meio definido XDM2. Foi utilizada a estirpe 9a5c de X. fastidiosa mantida nesse mesmo meio de cultura. A medida da taxa de crescimento bacteriano foi realizada através de leituras de densidade óptica durante dezesseis dias com intervalos de 48 horas. A avaliação da viabilidade celular foi realizada através da contagem de unidade formadora de colônia (UFC) por diluição seriada. As duas avaliações apresentaram uma alta correlação (R2= 0,91) verificada através de regressão exponencial. O início da fase estacionária foi obtido após 10 dias de crescimento. De posse dos dados de UFC, foi possível calcular o tempo de geração da X. fastidiosa no meio XDM2, de aproximadamente 21 horas. Comparando o tempo de geração obtido na curva de crescimento em meio PW (11,37h), foi comprovado que a bactéria apresenta um crescimento mais rápido em meio PW do que no meio definido XDM2. Outro aspecto interessante revelado no estudo do genoma funcional da X. fastidiosa está relacionado à expressão de genes associados à patogenicidade. O principal mecanismo de patogenicidade é a formação de biofilme no xilema da planta hospedeira conduzindo ao bloqueio dos vasos do xilema. Análise da expressão diferencial de genes desse fitopatógeno em condição de virulência e durante a formação do biofilme revela padrões de genes associados à adaptação e competitividade no ambiente do hospedeiro. Esses genes possivelmente são ativados no biofilme maduro e são essenciais para sua manutenção na planta. Além disso, sabe-se que bactérias que formam biofilme apresentam resistência crescente a compostos... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Based on informations generated after the genome sequencing, a series of culture media of defined composition were developed (XDM1, XDM2, XDM3, XDM4 e XDM5). Therefore, one of the objectives of the present work was to establish the growth curve of X. fastidiosa in the defined medium XDM2. For this, we utilized the 9a5c strain of X. fastidiosa maintained in this medium. The measurement of the bacterial growth rate was done by optical density analysis during sixteen days with intervals of 48 hours. The evaluation of cellular viability was carried out counting the colony units forming (CFU) by serial dilution. Both evaluations presented a high correlation (R2 = 0,91) verified by exponential regression. The beginning of the stationary phase was observed after ten days of growth. With the data of CFU, it was possible to calculate the generation time of X. fastidiosa in XDM2 medium, estimated to be of approximated 21 hours. Comparing the generation time obtained for the growth curve in PW medium (11,37 hours), we proved that the bacteria grow faster in PW compared with the defined medium XDM2. Another interesting aspect reveled by the study of functional genome of X. fastidiosa is related to the expression of genes associated with pathogenicity. The main mechanism of its pathogenicity is the formation of a biofilm in the xylem of the host plant, causing the blockage of the xylem vessels. Analysis of the differential expression of genes of this phytophatogen in condition of virulence and during the biofilm formation reveals standards associated to adaptation and competition in the host environment. These genes are possibly activated in the mature biofilm and are essential for its maintenance in the plant. Besides, it is known that bacteria that form biofilm present elevated resistance to antimicrobial compounds while biofilm is structured, like antibiotics, heavy metals... (Complete abstract click electronic access below)
Orientador: Marcos Antonio Machado
Coorientador: Alessandra Alves de Souza
Banca: Ivan Maia de Godoy
Banca: Henrique Ferreira
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25

Kruger, Fedra Gidget Quijano 1970. "Adubação mineral, orgânica e biodinâmica de yacon (Polymnia sonchifolia Poep & Endl) : rendimento, qualidade e armazenamento /." Botucatu : [s.n.], 2003. http://hdl.handle.net/11449/103265.

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Orientador: Francisco Luiz Araújo Câmara
Resumo: Com o objetivo de avaliar o efeito da adubação na produção, qualidade e conservação pós-colheita de yacon, foram instalados dois ciclos de cultivo na Fazenda Experimental Lageado da UNESP-Botucatu. Em ambos os cultivos, os tratamentos constaram de testemunha sem adubação (Test), adubações minerais NPK, com adição ou ausência de micronutrientes e parcelamento do K em três ou seis vezes, conforme o tratamento, adubações orgânicas com composto orgânico (Comp), composto biodinâmico (Biod) e vermicomposto (Verm). Em ambos os cultivos, a adubação orgânica apresentou eficiência similar à adubação mineral para as características massa fresca de raízes, altura das plantas, número de hastes e de raízes, teor de frutose e textura de raízes, destacando-se os tratamentos "Biod", "Verm", 'K3+M'. No primeiro cultivo, a adubação orgânica promoveu massa fresca de rizóforos e teores de proteína, cinza e fósforo superiores à adubação mineral. As raízes submetidas ao tratamento "K3+M" apresentaram teor de umidade significativamente superior àquelas dos tratamentos "Biod" e "Verm" no primeiro cultivo, e do "Comp" no segundo cultivo. Em póscolheita avaliaram-se raízes dos tratamentos "K3+M", "K3", "Comp" e "Biod" de ambos os cultivos. As raízes foram armazenadas durante duas épocas, em temperatura ambiente e em câmara fria, a 21,2 e 2l1oC, respectivamente, na primeira época, e a 25,3 e 4l1oC, respectivamente, na segunda época. O armazenamento em câmara fria reduziu a perda de massa e as atividades de peroxidase (POD) e polifenoloxidase (PPO) e manteve a aparência das raízes, quando comparado com o armazenamento em temperatura ambiente. Entretanto, ocorreram sintomas de dano pelo frio durante o armazenamento a 2oC, relacionados à maior atividade de POD e de PPO. Em ambas as épocas, as adubações orgânicas e mineral mostraram efeitos semelhantes na atividade... (Resumo completo, clicar acesso eletrônico abaixo).
Abstract: The aim of this work was to evaluate the effect of fertilization on yield, quality and postharvest conservation of yacon roots. Thus, two yield experiments were carried out at the FCA-UNESP - University - Botucatu. In both experiments the treatments consisted in fertilization absence (Test), mineral fertilization NPK, with or without micronutrients and K shared at three or six times according to treatments, organic fertilization with compost (Comp), compost plus biodynamic compounds (Biod) and vermicompost (Verm). At harvest, there were no differences in roots fresh matter, plant height, numbers of steams and roots, fructose content and texture with organic and mineral fertilizers. The "Biod", "Verm" and "K3+M" fertilizations showed better results than others. As far yield is concerned, in the first experiment, the organic fertilization, as compared to mineral fertilization, resulted in highest values of rizophores fresh matter, protein, ashes and phosphorus contents. "K3+M" treatment increased root moisture more than "Biod" and "Verm" at first experiment, and than "Comp" at the second one. Yacon roots of both yield experiments from "K3+M", "K3", "Comp" and "Biod"' treatments were stored during two different periods, under environmental conditions and refrigeration, at 21,2oC and 2l1oC, respectively, at first period, and at 25,3oC and 4l1oC, respectively, at second period. The refrigeration conditions resulted in reduction of weight loss, enzymes activities (POD and PPO) and even showed better appearance of yacon roots. However, yacon roots exposed to 2oC developed chilling injury symptoms, correlated with the high POD and POD activities at 2oC. During the storage periods, the POD activity was no different in roots grown using mineral or organic fertilizers, yet, mineral fertilization resulted in high PPO activity in roots stored under 21,2oC... (Complete abstract, click eletronic address below).
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Silva, Luana Faria. "Identificação e caracterização da microbiota lática isolada de queijo mussarela de búfala /." São José do Rio Preto : [s.n.], 2010. http://hdl.handle.net/11449/94833.

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Orientador: Ana Lúcia Barretto Penna
Banca: Kátia Sivieri
Banca: Eleni Gomes
Resumo: No Brasil, o queijo Mussarela elaborado com leite de búfala, tem uma boa aceitação pelos consumidores e mercado em expansão. Entretanto, poucas são as pesquisas em âmbito nacional sobre a microbiota e influência das bactérias ácido-láticas utilizadas na produção, sobre a qualidade tecnológica deste queijo. O objetivo deste trabalho foi compor um banco de culturas representativo da microbiota isolada de queijo Mussarela fabricado com leite de búfala e efetuar a caracterização das bactérias ácido-láticas (BAL). Foram realizadas três coletas em dois laticínios (Laticínios A e B), em diferentes etapas do processo de fabricação, assim como no produto acabado (queijo Mussarela e soro de conservação) recém processado e com 14 e 28 dias de estocagem. Foi feita a contagem de colônias viáveis, isolamento dos mesófilos e termófilos, caracterização morfológica por coloração de Gram e teste de catalase. Foram obtidos 313 isolados que apresentaram características de BAL. As culturas isoladas das amostras do queijo do Laticínio B foram identificadas pela técnica de RAPD e sequenciamento do gene 16S rRNA e caracterizadas quanto à atividade acidificante, capacidade de utilizarem o citrato, atividade proteolítica e capacidade de produzirem compostos voláteis precursores de aromas. Para os dois laticínios, a população de microorganismos termófilos prevaleceu sobre os mesofilos. Os isolados foram identificados como Lactobacillus fermentum, Lactobacillus casei, Lactobacillus delbrueckii, Lactobacillus delbrueckii subsp. bulgaricus e Leuconostoc mesenteroides. A velocidade máxima de acidificação para os isolados variou de 0,0005 e 0,0305 unidades de pH por minuto após 20 min e 18 h 50 min do início do processo de fermentação, respectivamente para termófilos e mesófilos. O tempo... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: In Brazil, the Mozzarella cheese prepared with buffalo milk has a good acceptance and market expansion. However, there are few national studies about microflora and influence of lactic acid bacteria, used in production, on the technological quality of this cheese. The aim this study was to compose a representative bank of the microbial cultures isolated from Mozzarella cheese produced with buffalo milk and to characterize the lactic acid bacteria (LAB). Three collections were performed in two dairy (Dairy A and B) at different stages of the manufacturing process as well as the finished product (Mozzarella cheese and whey conservation) newly processed and with 14 and 28 days of storage. It was followed a count of viable colony, isolation of mesophiles and thermophiles, morphological characterization by Gram staining and catalase test. It was obtained 313 isolates that exhibited characteristics of LAB. The cultures isolated of the cheese samples of the cheese from the Dairy B were identified by RAPD and 16S rRNA gene sequencing and characterized by acidifying activity, ability to utilize citrate, proteolytic activity and ability to produce volatile compounds that are flavor precursors. At two dairies, the population of thermophilic microorganisms was higher than mesophylic. The isolates were identified as Lactobacillus fermentum, Lactobacillus casei, Lactobacillus casei, Lactobacillus delbrueckii, Lactobacillus delbrueckii subsp. bulgaricus and Leuconostoc mesenteroides. The top speed of acidification for the isolates ranged from 0.0005 and 0.0305 pH units per minute after 20 minutes and 18:50 of the beginning of the fermentation process, respectively for thermophiles and mesophiles. The time required to reach the pH 5.0 ranged from 4h50min to 60h the beginning of... (Complete abstract click electronic access below)
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Veronezi, Carolina Médici. "Avaliação da composição química de óleos extraídos de sementes de abóboras (Cucurbita sp) /." São José do Rio Preto : [s.n.], 2011. http://hdl.handle.net/11449/88374.

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Orientador: Neuza Jorge
Banca: Sabria Aued-Pimentel
Banca: Mieko Kimura
Resumo: Cresce a busca por alimentos mais saudáveis, principalmente de origem vegetal, que são constituídos por substâncias benéficas ao organismo. Essas substâncias, denominadas de compostos bioativos, ajudam na redução do risco de doenças crônico-degenerativas e outras. Dentre esses alimentos, encontram-se os frutos. Porém, ainda são escassas as informações sobre a composição nutricional de certos frutos, principalmente no que se refere ao valor nutricional dos resíduos gerados em seu processamento. Assim, o presente trabalho teve como objetivo avaliar a composição centesimal de sementes de frutos da família Cucurbitaceae cultivadas no Brasil e caracterizar os seus óleos a fim de identificar compostos bioativos para a possível aplicação em alimentos. As sementes de abóboras das variedades Nova Caravela, Mini Paulista, Menina Brasileira (Cucurbita moschata) e Moranga de Mesa (Cucurbita maxima) foram caracterizadas quanto à umidade, lipídios, proteínas, cinzas e carboidratos totais, e os óleos dessas sementes quanto às propriedades físico-químicas, além do perfil de ácidos graxos, teores de tocoferóis, carotenoides e compostos fenólicos totais. Os resultados foram submetidos à análise de variância e as diferenças entre as médias foram testadas a 5% de probabilidade pelo teste de Tukey, por meio do programa ESTAT, versão 2.0. Verificou-se que todas as sementes possuem composição centesimal semelhante, apresentando teores relativamente elevados de lipídios (33-42%) e proteínas (29- 34%). Com relação às propriedades físico-químicas, todos os óleos apresentam valores dentro das faixas características dos óleos vegetais comestíveis. Os principais ácidos graxos encontrados foram o linoleico (40-47%) e oleico (28-30%), que perfizeram um total de 70 a 78%, sendo o óleo das sementes das abóboras da variedade Moranga de Mesa o mais insaturado... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The search for healthier foods is increasing, mainly for the ones of vegetable origin, which are composed of substances that are beneficial to the organism. These substances, known as bioactive compounds, help reduce the risk of chronic degenerative diseases and others. Fruits are among these foods. However, there still is little information about the nutritional composition of certain fruits, especially regarding the nutritional value of the waste generated by their processing. Thus, this study aimed to analyze the proximate composition of seeds from Cucurbitaceae fruit family, grown in Brazil and to characterize their oils, in order to identify bioactive compounds for possible application in food. The seeds from Nova Caravela, Mini Paulista, Menina Brasileira (Cucurbita moschata) and Moranga de Mesa (Cucurbita maxima) pumpkin varieties were characterized as moisture, lipids, proteins, ash and total carbohydrates, and the oils from these seeds, as to their physicochemical properties, as well as the fatty acid profile, the levels of tocopherols, carotenoids and total phenolic compounds. The results were subjected to variance analysis and the differences between means were tested at 5% probability by Tukey test, using the ESTAT program, version 2.0. It was found that all seeds have similar composition, with relatively high levels of lipids (33-42%) and protein (29-34%). About the physicochemical properties, all the oils present values within the range for edible vegetable oils. The main fatty acids found were linoleic (40-47%) and oleic (28-30%), which totalized 70 to 78%, highlighting Moranga de Mesa seed oil as the most unsaturated one. Regarding total tocopherols, Menina Brasileira stood out (386.43 mg/kg). However, regarding the carotenoids and phenolic compounds, Mini Paulista stood out, with 26.8 µg/g and 3.62 mg GAE/g, respectively
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28

Williams, Howard R. "Compound semiconductor material manufacture, process improvement." Thesis, University of South Wales, 2002. https://pure.southwales.ac.uk/en/studentthesis/compound-semiconductor-material-manufacture-process-improvement(d0373158-08d9-4332-9278-f5353203dcd0).html.

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IQE (Europe) Ltd. manufactures group III/V compound semiconductor material structures, using the Metal Organic Vapour Phase Epitaxy process. The manufactured ranges of semi-conducting materials are relative to discrete or multi-compound use of Gallium Arsenide or Indium Phosphide [III/V]. For MOVPE to compete in large-scale markets, the manufacturing process requires transformation into a reliable, repeatable production process. This need is identified within the process scrap percentage of the process when benchmarked against the more mature Si-CVD process. With this wide-ranging product base and different material systems, flexible processes and systems are essential. The negative impact however, of this demanded flexibility is a complex system, resulting in instability. Minor fluctuations in time, flow, pressure, temperature, or composition in the manufacturing process, will lead to characteristic differences in the produced material [product], when comparing the prescribed run to the actual run. The product profile changes very rapidly, correspondingly the failure profile of the process is equally as dynamic, it is essential therefore that the analysis and projected activities and actions can be identified and consolidated in a timely manner. This project evaluates the process used by IQEE to manufacture III/V compound semi-conducting material structures and uses the business performance to identify the process drivers. One year's [1997] business and process information is used for a single iteration of the improvement cycle. These drivers are then utilised as operators and offer the critical weaknesses in the process related to performance blockages. Some of the techniques utilised in the process evaluation and cause derivation; are original contributions specifically derived for use with a multi-platform complex process with multiple cause and effect operators. A double reporting FMEA contributes a differing rank for like machines running differing products, offering a machine specific failure profile. A novel composite of P-diagram and process flow techniques enables determination of activity influences confirming the key failure mechanism as previously identified by the business risk analysis. This project concludes by nominating the key failure mechanism accounting for 41% of the approximate 50% scrap figure identified again within the business risk analysis. The effects attributed to this failure mechanism are 2- dimensionally analysed utilising an original double operating FMEA, plotting effect to effect for the individual causes, offering a prioritised list of failure categories. The highest priority failure mode is addressed by an equipment design exercise, resulting in an overall 10% sales potential recontribution.

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Figadère, Bruno. "Les composes organomanganeux mixtes : addition 1-2 selective sur des aldehydes ou des cetones portant un groupe fonctionnel, enolisation regioselective de cetones : application en synthese." Paris 6, 1987. http://www.theses.fr/1987PA066371.

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Les reactifs organomanganeux rmnx(x=cl, br, i; r=n-, sec- t-alkyl, alcenyl, aryl, alcynyl) s'additionnent aux aldehydes et cetones fonctionnels pour donner selectivement les alcools correspondant avec d'excellents rendements. Les reactifs rmnz(z=nphme) enolisent les cetones avec une excellente regioselectivite. Les enolates manganeux ainsi prepares sont tres aisement acyles, silyles, alkyles, hydroxyalkyles, avec des rendements de 60% a 90%, a la temperature ambiante

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30

Shen, Weilin. "Role of stress pattern in production and processing of compound words and phrases in Mandarin Chinese." Thesis, Sorbonne Paris Cité, 2015. http://www.theses.fr/2015PA05H108/document.

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La présente thèse étudie le rôle de l'accent prosodique (accent de mot vs. accent de syntagme) lors du traitement auditif de paires minimales ambigües (mots composés vs. syntagmes) du chinois mandarin. Deux types de paires minimales ont été utilisés: 1) Mots composés avec un ton neutre (ex: dong3xi0 « chose ») vs. Syntagme avec un ton plein (ex: dong3xi1 « est et ouest ») qui se distinguent par la réalisation du ton sur la syllabe finale ; 2) Mots composés Verbe-Nom (VN) (ex: 'chaofan « riz frit ») vs. Syntagmes Verbe-Objet (VO) (ex: chao'fan « frire du riz ») se distinguant par la position de l'accent prosodique. Nos données comportementales et neurophysiologiques démontrent que : 1) la syllabe finale est plus longue et l'étendue de la F0 est plus large dans les VO que dans les VN, 2) la prosodie assiste le système de traitement pour anticiper la structure morphologique des séquences ambigües, et 3) un traitement hiérarchique « de droite-à-gauche » des informations prosodiques en complément d'un traitement séquentiel « de gauche-à-droite » prend place en chinois mandarin. Prises dans leur ensemble, nos données précisent la description fonctionnelle et structurale du modèle Prosody-Assisted-Processing (PAP) pour le chinois mandarin
The present thesis investigates the role of prosodic stress (i.e. lexical versus phrasal stress) on the auditory processing of Mandarin Chinese ambiguous compound /phrase minimal pairs. Two types of compound/phrase minimal pairs were used: 1) Compound word with a neutral tone (e.g. dong3xi0 "thing") vs. phrase with a full tone (e.g. dong3xi1 "east and west") distinguished by the final syllable tone realization; 2) Verb-Noun (VN) compound word (e.g. 'chaofan "fried rice") and Verb-Object (VO) phrase (e.g. chao'fan "fry the rice") distinguished by the position of the prosodic stress. Combined behavioral and neurophysiological data demonstrate that 1) the final syllable was more lengthened and the F0 range was larger in VO than in VN, 2) prosodic structure does assist the processing system in anticipating morphological structure, and 3) a right-to-left hierarchical processing of prosodic information in addition to a sequential left-to-right one is involved during the processing of ambiguous spoken sequences in Mandarin Chinese. Taken together, our findings allowed us to precise the functional and structural description of the Prosody-Assisted-Processing (PAP) model for Mandarin Chinese

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Iloughmane-Gaspard, Hafida. "Ene reactivite d'alcenylsilanes et -germanes : synthese et stabilisation de metalloles du groupe 14." Toulouse 3, 1986. http://www.theses.fr/1986TOU30214.

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La synthese d'alcools allyliques organometalliques du groupe 14 (si,ge) a ete effectuee par oxydation de composes ethyleniques (photo-oxygenation ; epoxydation/rearrangement). Ces alcools ou leurs esters ont ete valorises en tant que precurseurs des premiers metalloles, isologues des cyclopentadienes, c-non substitues ou c-methyles qui ont ete stabilises par complexation-pi (fe,co). L'auteur decrit plus de 100 produits organometalliques nouveaux dont les structures moleculaires sont etablies par spectrometries de resonance magnetique nucleaire, de masse, photo-electronique et de diffraction des rayons x. Les mecanismes des reactions de cycloaddition, d'oxydation et d'elimination mises en jeu au cours de ce travail sont discutes

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32

Herman, Thierry. "Acylation et silylation énantiosélectives de diols méso ou prochiraux." Rouen, 1988. http://www.theses.fr/1988ROUES020.

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Ho, Ka Yee. "Nanostructured environmental catalysts for carbon monoxide and volatile organic compounds removal /." View abstract or full-text, 2006. http://library.ust.hk/cgi/db/thesis.pl?EVNG%202006%20HO.

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Lecouve, Jean-Pierre. "Organométalliques vinyliques à fonction carbonylée masquée : application à la synthèse du rétinal." Rouen, 1986. http://www.theses.fr/1986ROUES016.

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On prépare une série d'organolithiens vinyliques par échange brome-lithium, utilisés ensuite dans 5 synthèses du rétinal à partir de la β-ionone. Les acétals, oméga-lithiés permettent d'aboutir en deux étapes au rétinal. Les éthers d'énols ω-lithiés présentent une grande réactivite avec les aldéhydes, et les cétones, une grande sélectivité, permettent des rendements élevés et la libération du carbonyle de l'adduit intermédiaire, simultanément avec le départ de l'hydroxyde dans des conditions douces. Pour la première fois, des organométalliques vinyliques à carbonyle masqué comportant 3 doubles liaisons conjuguées ont été préparés, permettant l'accès direct au rétinal à partir de la β-ionone

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35

Burnell, Erica Sinead. "Synthesis of biologically active compounds." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/synthesis-of-biologically-active-compounds(a009591b-d439-4ff7-9e6f-36199a33e7c8).html.

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Part 1 describes the synthesis of (2S,3S,4R,5R)-5-(6-(((7-bromo-2-(dimethylamino)-4-((3-methylisoxazol-5-yl)methoxy)benzo[d]oxazol-5-yl)methyl)amino)-9H-purin-9-yl)-3,4-dihydroxy-N-methyltetrahydrofuran-2-carboxamide, a selective A3 adenosine receptor agonist, and one of a number of adenosine analogues designed by Muscagen Ltd. with the purpose of treating cardiac ischaemia. The target compound was derived from a condensation of the known modified adenosine, (3aS,4S,6R,6aR)-6-(6-chloro-9H-purin-9-yl)-N,2,2-trimethyltetrahydrofuro[3,4-d][1,3]dioxole-4-carboxamide with 5-(aminomethyl)-7-bromo-N,N-dimethyl-4-((3-methylisoxazol-5-yl)methoxy) benzo[d]oxazol-2-amine. The benzoxazole amine fragment was synthesised from commercially available nitroresorcinol. Part 2 details the synthesis of two potential M1 muscarinic receptor agonists -(3aS*,7R*,7aR*)-3,7-dibenzyl-3a-cyclobutylhexahydro-2H-pyrano[3,4-d]oxazol -2-one and (3aSR,7RS,7aRS)-3,5,7-tribenzyl-3a-cyclobutylhexahydrooxazolo[4,5 -c]pyridin-2(3H)-one, part of a series of compounds designed by Muscagen Ltd. for the treatment of Alzheimer’s disease. Both targets were synthesised from the known carbamate intermediate, (S)-benzyl (1-((tert-butyldimethylsilyl) oxy)-2-cyclobutylbut-3-en-2-yl)carbamate, which was available from commercially available cyclobutyl carboxylic acid. Part 3, the final part, describes efforts made towards the total synthesis of the natural product, phomactin A, a desirable target for its biological activity as a platelet activating factor antagonist, in addition to its structural complexity. Building on previous research carried out in the group, advanced intermediate (2S*,3R*,5R*,12S*,13R*,15R*,E)-16-(hydroxymethyl)-5,9,12,13-tetramethyl-4-oxatricyclo[10.3.1.03,5]hexadeca-1(16),8-diene-2,15-diol was synthesised from a macrocyclic intermediate tert-butyldiphenyl (((1S*,2S*,4E,8E,10R*,12S*,14R*) -1,4,8,14-tetramethyl-15-methylene-2-(phenylsulfonyl)-10-((2-(trimethylsilyl) ethoxy)methoxy)bicyclo[9.3.1]pentadeca-4,8-dien-12-yl)oxy)silane.

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Leung, Pou Ian. "Sesquiterpenes emission from common airborne fungal species /." View abstract or full-text, 2009. http://library.ust.hk/cgi/db/thesis.pl?EVNG%202009%20LEUNG.

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Kwong, Chi Wai. "Catalytic ozonation of VOCS over different porous materials /." View abstract or full-text, 2009. http://library.ust.hk/cgi/db/thesis.pl?EVNG%202009%20KWONG.

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Koch, Katrin. "Crystal structure, electron density and chemical bonding in inorganic compounds studied by the Electric Field Gradient." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2009. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-24233.

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The goal of solid state physics and chemistry is to gain deeper understanding of the basic principles of condensed matter. This ongoing process is achieved by the combination of experimental methods and theoretical models. One theoretical approach are the so-called first-principles calculations, which are based on the concept of density functional theory (DFT). In order to test the reliability of a band structure calculation, its results have to be compared with experiments. Since the electron density, the main constituent of DFT codes, cannot be directly determined experimentally with sufficient accuracy (e.g., by X-ray diffraction), other experimentally available properties are needed for the comparison with the calculation. A quantity that can be measured with high accuracy and that provides indirect information about the electron density is the electric field gradient (EFG). The EFG reflects local structural symmetry properties of the charge distribution surrounding a nucleus: the EFG is nonzero if the density deviates from cubic symmetry and therefore generates an inhomogeneous electric field at the nucleus. Since the EFG is highly sensitive to structural parameters and to disorder, it is a valuable tool to extract structural information. Furthermore, the evaluation of the EFG can provide valuable insight into the chemical bonding. Whereas the experimental determination of the quadrupole frequency and the closely related EFG has been possible for more than 70 years, reliable values for calculated EFGs could not be obtained before 1985, when an EFG module was implemented in the full-potential, linearised-augmented-plane-wave code WIEN. Since the full-potential local-orbital minimum-basis scheme FPLO is numerically very efficient and its local-orbital scheme allows an easy analysis of the different contributions to the EFG, one goal of this work was the implementation of an EFG module within the FPLO code. The newly implemented EFG module was applied to different systems: starting from simple metals, then approaching more complex systems and finally tackling strongly correlated oxides. Simultaneously, the EFGs for the studied compounds were determined experimentally by NMR spectroscopists. This close collaboration enables the comparison of the calculated EFGs with the experimental observations, which makes it possible to extract more physical and chemical information from the measured values regarding structural relaxation, distortion, the chemical bond or the relevance of electron correlation. In the last part of this work, the importance of corrections that go beyond the EFG are discussed. Such corrections arise for any multipole order of the hyperfine interactions, and are due to electron penetration into the nucleus. A correction similar to the isomer shift, coined here the "quadrupole shift" is examined in detail.

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39

Réau, Régis. "Phospholes et phosphanorbornadienes : valorisation en catalyse homogene." Toulouse 3, 1988. http://www.theses.fr/1988TOU30162.

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Les ligands etudies ont ete utilises d'une part en association avec des complexes cationiques du palladium en reactions de dimerisation de l'acrylate de methyle, de codimerisation de l'acrylate de methyle et du butadiene-1,3 et de telomerisation de ce dernier avec le methanol; d'autre part en association avec des complexes de rhodium dans l'hydroformylation de l'hexene-1 de styrenes et de l'acrylate de methyle

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40

Chan, Man Nin. "Experimental measurements of phase transition and hygroscopic growth of water-soluble organic compounds in atmospheric aerosols /." View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?EVNG%202004%20CHAN.

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Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2004.
Includes bibliographical references (leaves 54-62). Also available in electronic version. Access restricted to campus users.

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41

Chakir, Abdelkhaleq. "Etude cinetique et modelisation du mecanisme d'oxydation a haute temperature de n-butane et de 1-butene." Paris 6, 1988. http://www.theses.fr/1988PA066132.

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L'etude experimentale de l'oxydation du butane et du butene-1 a ete effectuee en reacteur auto-agite par jets gazeux dans un large domaine de conditions experimentales (900-1200 k, 1 a 10 atm, rapports d'equivalents oxygene-hydrocarbure 0,1-4)

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42

Hannachi, Hassen. "Etudes cinetiques sous conditions atmospheriques simulees des reactions de composes carbonyles avec oh', o::(3), no'::(3) : consequences sur la chimie de basse troposphere." Paris 7, 1986. http://www.theses.fr/1986PA077213.

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43

Jones, Charlotte E. S. "Enantioselective homogeneous catalysts for the synthesis of fluorinated organic compounds." Thesis, University of St Andrews, 2011. http://hdl.handle.net/10023/2611.

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This thesis is divided into three main results chapters that reflect the path my research took. In the first results chapter, the first organocatalyst for the carbonyl-ene reaction was discovered and found to give high conversion using 1,3-bis(3,5-bis(trifluoromethyl)phenyl)thiourea. Various carbonyl and alkene precursors were examined in the ene reaction in both catalysed and uncatalysed reactions. It was found that ene reactions using fluoral and ethyl trifluoropyruvate give higher rates of reaction when compared to other carbonyl compounds. A novel enantiopure thiourea was synthesised and the ene reaction was catalysed enantioselectively to 33% e.e. In an attempt to catalyse the reaction to a further extent a new thiourea bonded to a P(=S)R2 group was developed. However, the intramolecular hydrogen bonding of this catalyst was thought to be so strong that this it did not catalyse the reaction. The synthesis of a chiral phosphoric acid was achieved but this was an unsuccessful catalyst in the ene reaction. Two component achiral thiourea and chiral acids were also examined in the ene and Mannich-type reaction. The new easily synthesised thiourea for this reaction has an interesting intermolecular hydrogen bonding coordination in the solid state. Asymmetric fluorination of ketoesters using palladium is a dynamic kinetic resolution. In the 2nd chapter cationic palladium complexes were synthesised and used to determine the optimum parameters for bidentate ligands in this reaction. Four carbon chain phosphines were found to give the highest conversion for this reaction among those ligands tested such as 1,4-bisdiphenylphosphinobutane (bite angle 99º). A new bis-phosphinous amide chiral ligand was developed with a bite angle of 96.7º. The dichloropalladium complex of this phosphine was isolated and structurally characterised. The use of the palladium complex in asymmetric fluorination was attempted however this was found to be unsuccessful. Mechanistic studies reveal that the formation of the desired cationic catalyst did not occur under conditions shown to work well for other palladium phosphine complexes. The ligand was investigated further in hydrogenation reactions. The phosphinous amide was protected as its borane and was used in the rhodium catalysed hydrogenation of alkenes to give high conversion and up to 93% e.e. The borane protected phosphinous amide was also found to catalyse the hydrogenation of acetophenone using copper complexes with up to 84% e.e for the hydrogenation of acetophenone, although conversion was quite low.

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44

Denys, Goument Colombe. "Dicétones-1,4 thiosubstituées." Rouen, 1988. http://www.theses.fr/1988ROUES023.

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45

BREUILLES, PASCAL. "Syntheses de dicetones un, quatre." Paris 6, 1988. http://www.theses.fr/1988PA066645.

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Trois nouvelles methodes de synthese de dicetones 1-4 sont proposees: la premiere par addition oxydante, a l'aide de sels de manganese et de cuivre, de cetones a des isopentenyl sulfones; la seconde par substitution allylique de sulfures ou de sulfones par des cetones enolisables; la troisieme par cycloaddition a une enone d'un nouveau reactif: la chloromethyl-2 allylphenylsulfone. Les produits de ces trois reactions sont des cetones comportant un groupe methylene en position 4 alors facilement transformees en dicetones par ozonolyse. L'utilite synthetique de ces trois methodes est illustree par la synthese de plusieurs composes naturels: pyrenophorine, acide chrysanthemique et jasmone

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46

Hammoud, Abdelhay. "Syntheses de pheromones et de molecules isosteres de pheromones d'insectes pour preciser les mecanismes moleculaires de la reconnaissance des signaux chimiques au niveau des recepteurs antennaires." Paris 6, 1988. http://www.theses.fr/1988PA066679.

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47

Carro, Tiffany. "Development and evaluation of a viable chicken egg assay to determine the metabolic fate of xenobiotic and other teratogenic compounds." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 137 p, 2007. http://proquest.umi.com/pqdweb?did=1372020111&sid=5&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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48

Khashoqji, Moayad. "Structural characterisation of novel poly-aryl compounds." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/structural-characterisation-of-novel-polyaryl-compounds(3fb1fac6-548a-4afc-8ac2-5a14885b0ba4).html.

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Poly-aryl, also known as polyphenylene compounds are a class of dendrimer, which contain a large number of aromatic rings. They are of interest because they display restricted rotation of their stearically congested aromatic rings. These extended structures have the potential to act as precursors for even larger aromatic systems and have many applications including electronic devices, drug delivery and catalysis. A total of 23 novel poly-aryl compounds have been examined using single crystal X-ray diffraction and a number of structural patterns have emerged. Six of the compounds contain alkynes and it has been observed that their conformation is governed by a combination of conjugation between the alkyne and aryl groups and inter-molecular interactions. In the more extended poly-aryl compounds steric congestion rules out any possibility of conjugation between the rings and their conformation is governed by intra-molecular non-bonded interactions in the core of the molecules and by inter-molecular interactions in their periphery. Where possible, solution NMR measurements were carried out on the poly-aryl compounds and confirmed that the solution structures are in agreement with those obtained from individual crystal.

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Bacon, John. "Conformational analysis of cyclohexandiols and related compounds." Thesis, University of South Wales, 1987. https://pure.southwales.ac.uk/en/studentthesis/conformational-analysis-of-cyclohexandiols-and-related-compounds(d78175ac-be32-45a5-907a-892feb68c54d).html.

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The conformational equilibria in disubstituted cyclohexanes containing polar groups lead to a diversity of conformational forms. In solution, the conformational preference is shown to be highly dependent upon the nature of the solvent. In the cyclohexandiol series, the formation of intramolecular and intermolecular hydrogen bonds determines the conformational preference with regard to the molecule as a whole and with respect to the rotamer conformation of the hydroxyl groups. Polar solvents capable of hydrogen bonding to the hydroxyl group have been shown to influence the position of equilibrium between the alternative chair conformations. In cyclohexanol, the equilibrium is always shifted towards the equatorial conformation. 13C nmr, 1H nmr, solution i.r. and matrix isolation i.r. techniques have been used to determine the conformational structures in the cyclohexandiol series and the nature of the solvent interactions. Two types of solvent interaction have been identified, a hydrogen bonded interaction and a non-bonded dipole interaction. A Computer Graphic Simulation has been used to' quantify the conformational energy differences and to rationalize the experimental results in terms of the Van der Waals repulsion energy. The experimental results give strong evidence that in cis cyclohexan-1,3-diol, two types of internal hydrogen bond exist in the diaxial conformation. The Computer Graphic simulation supports this reasoning on thermodynamic grounds.

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50

Ta, Yien Trung. "Pyridinium compounds as sensitisers for solar cells." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/pyridinium-compounds-as-sensitisers-for-solar-cells(c12215c0-d9f4-4e92-b311-660917846ce6).html.

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The work presented in this thesis concerns the synthesis and study of various RuII polypyridyl complexes and organic chromophores which incorporate strongly electron-accepting and π-conjugated pyridinium groups. Several of these compounds have been studied as potential sensitisers for solar cell applications.The N3 dye, cis-RuII(NCS)2(dcbpy)2 (dcbpy = 4,4'-dicarboxy-2,2'-bipyridyl) has been synthesised in pure form and excellent yield via ester hydrolysis of cis-RuII(NCS)2(Et2dcbpy)2 (Et2dcbpy = 4,4'-di(ethoxycarbonyl)-2,2'-bipyridyl). This well known complex is used as a benchmark for comparison purposes with our novel pyridinium compounds. A single-crystal X-ray structure has been obtained for the new complex cis-RuIICl(NCS)(Et2dcbpy)2.Three new 4,4':2',2":4",4""-quaterpyridinium pro-ligand cations along with several known ones have been synthesised and isolated as their chloride salts. Single-crystal X-ray structures have been determined for one of these salts and also for an unexpected protonated derivative. These pro-ligands have been used to prepare two series of RuII polypyridyl complex salts. A series of eleven new complexes of the form cis-[RuII(bpy)2(LA)]4+ and fourteen of the form cis-[RuIIX2(LA)2]4+ (bpy = 2,2'-bipyridyl; LA = quaterpyridinium-based ligand; X = NCS⁻ or Cl⁻) have been synthesised and isolated as their hexafluorophosphate salts. The various characterisation techniques used include 1H NMR spectroscopy and mass spectrometry. The UV-vis spectra show intense intraligand π→π* absorptions in the UV region and low energy metal-to-ligand charge-transfer (MLCT) bands in the visible. Small shifts in the MLCT bands correlate with changes in the electron-accepting strength of the ligand LA. The UV-vis absorption profiles of the salts cis-[RuIIX2(LA)2][PF6]4 cover the entire visible region extending well into the near-IR, with MLCT bands much more red-shifted than those of their cis-[RuII(bpy)2(LA)][PF6]4 relatives and the N3 dye. Cyclic voltammograms show quasi-reversible or reversible RuIII/II oxidation waves and ligand-based reductions. The variations in the redox potentials correlate with changes in the pyridinium substituents, and also with the MLCT energies. Single-crystal X-ray structures have been solved for three of the new cis-[RuII(bpy)2(LA)][PF6]4 salts. Four carboxylate-functionalised RuII polypyridyl compounds have been tested as dye sensitisers on both TiO2 and ZnO electrodes, but only low overall efficiencies are achieved. A series of eight new stilbazolium compounds has been synthesised and fully characterised as their hexafluorophosphate salts. Single-crystal X-ray structures have been determined for a new picolinium precursor and three of the ester-substituted stilbazolium compounds. The UV-vis spectra of these organic chromophores feature intense intramolecular charge-transfer (ICT) bands. Four acid-functionalised compounds have been tested as dye sensitisers on both TiO2 and ZnO surfaces, with the most encouraging preliminary results observed for the latter.Time-dependent density functional theory (TD-DFT) calculations were carried out on six of the new dye sensitisers to clarify their electronic/optical properties. TD-DFT-derived depictions of the lowest unoccupied molecular orbitals (LUMOs) show negligible electron density near the acid-functionalities. This factor, along with possible energy level mismatch of the excited-state donor orbitals with the conduction band edge of the semiconductor, may be the cause of inefficient electron injection and thus poor photovoltaic performance of our new pyridinium-based dyes.

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Dissertations / Theses on the topic 'Compound. eng'

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