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

Aplicação de vinhaça e do extrato de palhiço de cana-de-açúcar no controle de plantas daninhas / Use of vinasse and sugarcane straw extract on weed control

Voll, Cristiano Elemar 30 September 2005 (has links)
A cultura de cana-de-açúcar (Saccharum officinarum L.) tem presença marcante na história do Brasil e possui grande expressão na economia nacional atual. O objetivo deste trabalho visou determinar a ocorrência de efeitos da vinhaça e do extrato de palhiço da cana-de-açúcar no controle de plantas daninhas. Os experimentos foram conduzidos em casa de vegetação. Os tratamentos utilizados foram: vinhaça a 0, 100, 200, 300 m³.ha-1, extrato aquoso de palhiço equivalentes à 0, 10, 15 e 20 t.ha-1, e suas combinações. As espécies de plantas daninhas avaliadas no experimento foram: a corda-de-viola (Ipomoea grandifolia Dammer O’Don), picão-preto (Bidens pilosa L.), capimcolchão (Digitaria horizontalis Willd) e capim-marmelada (Brachiaria plantaginea Link Hitchc). Um experimento adicional foi conduzido para determinar os efeitos de ácido aconítico (AA) analítico, determinado na vinhaça e no extrato pela cromatografia líquida, sobre a germinação destas plantas daninhas. As doses foram de 0, 1, 2 e 3 mmol/gerbox de AA. Os experimentos foram conduzidos em delineamentos estatísticos de blocos casualizados, com quatro repetições. As avaliações foram a emergência das plantas daninhas, a biomassa seca e o altura da parte aérea e comprimento das raízes de 10 plantas daninhas/vaso. Os resultados obtidos indicaram que a emergência das plantas daninhas I. grandifolia, B. pilosa e D. horizontalis foi reduzida pela aplicação de vinhaça após 7 dias de semeadura. Aos 15 dias após semeadura e aplicação de vinhaça, somente houve redução sobre a emergência das plantas daninhas B. pilosa e I. grandifolia. As espécies suscetíveis ao extrato foram B. pilosa e D. horizontalis aos 7 dias após semeadura. O ácido aconítico reduziu a germinação de I. grandifolia e B. pilosa. Conclui-se que a vinhaça e o extrato apresentam efeitos alelopáticos sobre algumas espécies daninhas, devidos à presença de AA. / Sugarcane (Saccharum officinarum L.) has major presence in the history of Brazil and possess great expression in the current national economy. The objective of this work was to determine the occurrence effects of vinasse and raw extract of sugarcane in the control of weeds. The experiments were carried out in greenhouse. Treatments used were vinasse at 0, 100, 200, 300 m³.ha -1 and watery extract of raw sugarcane equivalents of 0, 10, 15 and 20 t.ha -1, and its combinations. Weed species used in the experiment were morningglory (Ipomoea grandifolia Dammer O’Don), starbristtle (Bidens pilosa L.), large crabgrass (Digitaria horizontalis Willd) and alexandergrass (Brachiaria plantaginea Link Hitchc). An additional experiment was carried out to determine the effect of pure aconitic acid (AA), determined in the vinasse and extract by liquid chromatography, on the germination of these weeds. The aconitic acid levels used were 0, 1, 2 and 3 mmol of AA /gerbox. Experiments were statistical designs of randomized blocks, with four replicates. Emergence of weeds, dry biomass and aerial and root part lengths of 10 weeds/vase were determined. Results indicated that emergence of weed I. grandifolia, Bidens pilosa e D. horizontalis were reduced by vinasse application, at 7 days after sowing. After 15 days of sowing and vinasse application, the weeds B. pilosa and I.grandifolia have your emergency reduced. The susceptible species to the extract were B. pilosa and D. horizontalis at 7 after sowing. Aconitic acid reduced germination of I. grandifolia and B. pilosa. Conclusions were that vinasse and raw extract of sugarcane present allelopathic effects on some weeds, due to the presence of aconitic acid.
2

Aplicação de vinhaça e do extrato de palhiço de cana-de-açúcar no controle de plantas daninhas / Use of vinasse and sugarcane straw extract on weed control

Cristiano Elemar Voll 30 September 2005 (has links)
A cultura de cana-de-açúcar (Saccharum officinarum L.) tem presença marcante na história do Brasil e possui grande expressão na economia nacional atual. O objetivo deste trabalho visou determinar a ocorrência de efeitos da vinhaça e do extrato de palhiço da cana-de-açúcar no controle de plantas daninhas. Os experimentos foram conduzidos em casa de vegetação. Os tratamentos utilizados foram: vinhaça a 0, 100, 200, 300 m³.ha-1, extrato aquoso de palhiço equivalentes à 0, 10, 15 e 20 t.ha-1, e suas combinações. As espécies de plantas daninhas avaliadas no experimento foram: a corda-de-viola (Ipomoea grandifolia Dammer O’Don), picão-preto (Bidens pilosa L.), capimcolchão (Digitaria horizontalis Willd) e capim-marmelada (Brachiaria plantaginea Link Hitchc). Um experimento adicional foi conduzido para determinar os efeitos de ácido aconítico (AA) analítico, determinado na vinhaça e no extrato pela cromatografia líquida, sobre a germinação destas plantas daninhas. As doses foram de 0, 1, 2 e 3 mmol/gerbox de AA. Os experimentos foram conduzidos em delineamentos estatísticos de blocos casualizados, com quatro repetições. As avaliações foram a emergência das plantas daninhas, a biomassa seca e o altura da parte aérea e comprimento das raízes de 10 plantas daninhas/vaso. Os resultados obtidos indicaram que a emergência das plantas daninhas I. grandifolia, B. pilosa e D. horizontalis foi reduzida pela aplicação de vinhaça após 7 dias de semeadura. Aos 15 dias após semeadura e aplicação de vinhaça, somente houve redução sobre a emergência das plantas daninhas B. pilosa e I. grandifolia. As espécies suscetíveis ao extrato foram B. pilosa e D. horizontalis aos 7 dias após semeadura. O ácido aconítico reduziu a germinação de I. grandifolia e B. pilosa. Conclui-se que a vinhaça e o extrato apresentam efeitos alelopáticos sobre algumas espécies daninhas, devidos à presença de AA. / Sugarcane (Saccharum officinarum L.) has major presence in the history of Brazil and possess great expression in the current national economy. The objective of this work was to determine the occurrence effects of vinasse and raw extract of sugarcane in the control of weeds. The experiments were carried out in greenhouse. Treatments used were vinasse at 0, 100, 200, 300 m³.ha -1 and watery extract of raw sugarcane equivalents of 0, 10, 15 and 20 t.ha -1, and its combinations. Weed species used in the experiment were morningglory (Ipomoea grandifolia Dammer O’Don), starbristtle (Bidens pilosa L.), large crabgrass (Digitaria horizontalis Willd) and alexandergrass (Brachiaria plantaginea Link Hitchc). An additional experiment was carried out to determine the effect of pure aconitic acid (AA), determined in the vinasse and extract by liquid chromatography, on the germination of these weeds. The aconitic acid levels used were 0, 1, 2 and 3 mmol of AA /gerbox. Experiments were statistical designs of randomized blocks, with four replicates. Emergence of weeds, dry biomass and aerial and root part lengths of 10 weeds/vase were determined. Results indicated that emergence of weed I. grandifolia, Bidens pilosa e D. horizontalis were reduced by vinasse application, at 7 days after sowing. After 15 days of sowing and vinasse application, the weeds B. pilosa and I.grandifolia have your emergency reduced. The susceptible species to the extract were B. pilosa and D. horizontalis at 7 after sowing. Aconitic acid reduced germination of I. grandifolia and B. pilosa. Conclusions were that vinasse and raw extract of sugarcane present allelopathic effects on some weeds, due to the presence of aconitic acid.
3

Valorisation catalytique d’un acide carboxylique issu de l’industrie sucrière / Catalytic valorization of a carboxylic acid derived from sugarcane industry

Hneine, Waël 21 June 2016 (has links)
Ces travaux de thèse ont porté sur la conversion catalytique de l'acide aconitique (un co-produit de la filière canne à sucre) en molécules d'intérêt industriel. Par deux voies catalytiques. 1) Par catalyse homogène, hydrogénation de l'acide en polyols, a été étudiée dans un réacteur Batch à l'aide d'un complexe catalytique actif à base de Ru [Ru(acac)3/Triphos]. L'optimisation des différents paramètres réactionnels a été effectuée sur une réaction modèle, l'hydrogénation de l'acide succinique en 1,4-butanediol. Ultérieurement, ces conditions réactionnelles optimales ont été utilisées pour l'hydrogénation de l'acide aconitique et ont permis l'obtention d'un produit majoritaire, le 2-méthyl 1,4-butanediol. 2) Par catalyse hétérogène, la réaction d'hydro-cyclisation de l'acide aconitique en MTHF ou en lactones, a été réalisée en réacteur continue en présence de catalyseurs à base de cuivre en partant de solutions d'acide aconitique dans l'éthanol. Les conditions de test catalytiques et la synthèse du catalyseur ont été optimisées. Les caractéristiques des différents catalyseurs testés ont été réalisées en faisant recours à des techniques analytiques complémentaires (SBET, Analyse chimique, DRX, XPS et MET) afin de corréler les propriétés de surface à l'activité catalytique / This thesis is focused on the catalytic conversion of aconitic acid (a co-product of sugarcane industry) into molecules of industrial interest, by two catalytic ways. 1) By homogeneous catalysis, the acid hydrogenation into polyols, was carried out in a batch reactor using a Ru complex [Ru(acac)3/Triphos]. The various reaction parameters was optimized in the model reaction of hydrogenation of succinic acid into 1.4-butanediol. Subsequently, these optimal reaction conditions were used for the hydrogenation of aconitic acid and resulted to a predominant formation of 2-methyl 1,4-butanediol. 2) By heterogeneous catalysis, the hydro-cyclization reaction of aconitic acid into MTHF or lactones, was performed in a continuous reactor in the presence of copper catalysts, using aconitic acid solutions in ethanol as substrate. The different conditions of the catalytic test and catalyst synthesis was optimized. Furthermore, the different catalysts tested in this thesis work was characterized using complementary techniques (BET, Elementary analysis, XRD, XPS and TEM) in order to correlate the superficial properties to the catalytic activity

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