Rozprawy doktorskie na temat „Limonin”

The search for limonoids started long back when scientists started looking for the factor responsible for bitterness in citrus. Studies showed that limonoids are highly oxygenated, modified terpenoids and have recently attracted attention because compounds belonging to this group have exhibited a range of biological activities like insecticidal, insect antifeedant and growth regulating activity on insects as well as antibacterial, antifungal, antimalarial, anticancer, antiviral and a number of other pharmacological activities on humans. Based on this premise this paper has focused on technological, healthful and chemical aspects of the limonoids. -TECHNOLOGICAL APPROACH: Based on a project titled Enhancement of bioactive compounds isolated from agro-industrial wastes financially supported by the Italian Ministry of Education, a Sicilian juice company wanted to assess the possibility of transforming the waste by-product of citrus processing (pastazzo) in a resource trying to turn it into dietary fiber. To do that, the company has inserted a debittering line to the plant using an alkaline aqueous solution in order to extract flavanones and limonoids. In the present paper the operational conditions of debittering were evaluated and optimized by determining the limonin content of samples from various stages of fiber production; It was also verified if the recovery of limonin extracted was economically viable. -HEALTHFUL AND ORGANOLEPTIC CHARACTERISTICS: It has been established that U.S. producers are turning to organic farming system as a potential way to lower input costs, decrease reliance on nonrenewable resources, capture high-value markets at premium price, and boost-farm income. Organic production agriculture is characterized by inputs of biologically (non-synthetic) based fertilizers and pest management practices that are sustainable. In order to understand if the market source contributes to differences in bioactives content, the bio-actives content of fruits obtained from farmers' markets was compared to the content found in fruit purchased from retail grocery stores. Organoleptic properties, including Brix, TTA, color and pH were measured. Limonin, ascorbic acid and flavanoid contents were also determined. -SYNTHESIS AND CHARACTERIZATION OF FUNCTIONAL COMPOUNDS: Ehrlich s reagent, p-dimethylaminobenzaldehyde (DMBA) in hydrochloric acid, has a long history and is known as the coloring reagent of pyrrole. 2,3. When a solution of limonoids is treated with p-dimethylaminobenzaldehyde in acid environment the solution immediately change to red-purple until dark blue. This reaction has named Ehrlich s reaction and the purple coloring is probably due to the presence of an adduct compound with an electron-rich trisubstituted furan ring. In order to determine the structure of the limonin-DMBA and limonin glucoside-DMBA adducts, both compounds have been synthesized, purified and characterized. This project involves synthesis of the target compounds. MS analysis were conducted for the characterization of the isolated products.

The progress in biotechnological disciplines such as metabolic engineering or synthetic biology increased the interest of chemical and pharmaceutical industries to implement microbial processes for chemical synthesis. However, most microorganisms, e.g., Escherichia coli or Saccharomyces cerevisiae, used in biotechnological applications are not evolved by nature for the production of industrially relevant compounds, which are often hydrophobic, non-charged, volatile, or toxic to the microbial organisms. Bioprocess design relies on an integrated approach addressing pathway, cellular, reaction, and process engineering to combine the results of natural evolution with the demands of industrial applicability. In this thesis, the microbial de novo production and selective oxyfunctionalization of the highly volatile isoprenoid limonene has been investigated as a model system featuring reactants with challenging physicochemical characteristics. Key constraints that limit limonene biosynthesis and its oxyfunctionalization in recombinant E. coli, related to genetics, physiology, and reaction engineering, were identified and relieved.

O limoneno é um produto natural da classe dos terpenos, encontrado abundantemente em plantas cítricas e relatado na literatura como um composto com atividades farmacológicas interessantes, entre elas antibacteriana, antifúngica, antileishmania, nociceptiva e citotóxica. A presente tese relata a funcionalização do limoneno utilizando a Síntese Orgânica em Fase Sólida e a Síntese Orgânica Clássica (em solução). A partir da síntese orgânica em solução, especialmente através das reações de hidroformilação e hidroaminometilação, obtiveram-se vinte compostos. Os compostos foram testados para várias atividades farmacológicas in vitro, a saber: antibacteriana, antifúngica, anti-tripanossoma e anti-leishmania. Destes, dezessete foram testados para a atividade anti-leishmania in vitro contra formas promastigotas de L. (V.) braziliensis e sete apresentaram atividade superior ao fármaco pentamidina, utilizado como padrão no teste, com valores de IC50 entre 11,5 e 35,6 μM.
Limonene is a natural product from the terpene family, found in great proportions in citrical plants, being reported in the literature as having interesting pharmacological activities, such as antibacterial, antifungical, antileishmanial, nociceptive and citotoxic. This thesis reports the funcionalization of limonene via Solid-Phase Organic Synthesis and classical solution-phase synthesis. Twenty products were obtained from the solution-phase protocols, especially from reactions such as hydroformylation and hydroaminomethylation. The compounds were tested for several pharmacological activities, e.g.: antibacterial, antifungical, anti-tripanossomal and anti-leishmanial. Seventeen of those compounds were tested against in vitro promastigote strains of Leishmania (V.) braziliensis and seven compounds were found to have greater anti-leishmanial activity than pentamidine, the standard drug used in this test, presenting IC50 values ranging from 11,5 to 35,6 μM.

The study presented here consists in an original piece of work to better understand complex food packaging interactions. The majority of investigations on food polymer interactions related to orange juice and this provided a good base to our study (Literature reviews: cf. Chapters 1a and b). Additionally a rather remarkable finding in 1994 was that limonin, a trace bitter material found in some varieties of orange juice was rapidly absorbed by highly plasticised polyvinyl chloride (PVC plastisol) (Chapter 2). Several commercial absorbants are available for debittering, relying on limonin absorption on the large surface area of the highly porous absorbant pellets. However, the absorptive properties of the smooth plastisols apparently relied on a different mechanism. Limonin is a very large (470.5 g/mol) compound, but some preliminary experiments with another much smaller orange juice constituent d- of absorbates in plastisols, methods used earlier (Moisan 1980, Holland and Santangelo 1988) to measure solubilities and diffusion constants in packaging films could be advantageously used to survey these properties in a wide range of materials, including model compounds of various types, and a number of compounds which may be found in citrus juices (Chapters 3, 4 and 5). Experimentally, the method found most suitable was to use a ‘test film’ of pure plastisol which was wrapped tightly on both sides by a similar ‘supply film’ blended with 1 Molar test material (also called ‘absorbate’), setting up a concentration gradient. The inner test film was removed at regular intervals (minutes to hours) to measure (mainly by weighing) the uptake of the test reagent with time. Rather unexpectedly, it was found in a number of cases that the test film lost weight, either from the beginning, or after a period of time. Three main types of behaviour were identified: Type A lost weight from the beginning and over a long period of time, Type B gained weight initially and then lost weight, and Type C gained weight until a steady state was reached. Often the maximum, or near maximum, mass increase occurred within around 100 minutes, indicating a very rapid, liquid-like diffusion mechanism, in harmony with the rapid uptake of d-limonene and limonin. The major parameters of interest with these compounds are their diffusion rates and their solubilities, and in the presence of aqueous media (orange juice and other foodstuffs) the partition coefficient between the plastisol and water, which is related to the hydrophobicity function LogP for the compound. The major complicating factor in these measurements is the observation that the plasticiser materials themselves also migrate, in the reverse direction, because of the lower effective concentration in the supply film. This effect tends to be small, but is one explanation for the mass loss observed above, and cannot be ignored over the long term, nor in its practical applications to contamination in foods. There are many possible applications for the techniques described above. The removal or addition of compounds in food packaging itself is one. Upgrading foods, such as orange juice, commercially, is another. In many cases ‘scalping’ off-flavours or other minor components takes place exclusively through solid or liquid contact with the packaging. The removal from the headspace measured by the current gas permeation methods is irrelevant for the vast numbers of involatile, but easily diffusable compounds. For such compounds these novel applications are simple and rapid, require little specialised equipment, and fill a niche in the armoury of food and packaging chemists.

Orientador: Rubens Maciel Filho
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
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Resumo: Uma das olefinas de fontes renováveis de maior importância no Brasil é o Limoneno, terpeno que compõe cerca de 90% do óleo da casca da laranja. O Brasil é o maior produtor mundial de laranja, com uma produção, entre 2010-2011, de cerca de 15,33 milhões de toneladas do fruto, dos quais 89% da produção são destinadas à produção de suco, sendo a casca e o óleo fixo, resíduos do processo. A parte volátil do óleo é constituída majoritariamente de (R)-limoneno (90 %). Terpenos como o limoneno, podem ser submetidos a reações de oxidação catalítica nos quais os epóxidos são os principais produtos, e podem ser utilizados como precursores para uma ampla variedade de produtos como fármacos, fragrâncias e na fabricação de biopolímeros e resinas. Mediante ao exposto, este trabalho tem por objetivo o estudo da epoxidação de limoneno para a obtenção de epóxidos que possam ser utilizados como monômeros para a síntese de biomateriais para a construção de dispositivos médicos, sendo que avaliou-se sistemas epoxidativos contenho metiltrioxorênio, montmorilonita e alumina. O sistema mais promissor, utilizando H2O2 como oxidante, ?-Al2O3 como catalisador em acetato de etila, foi avaliado em condições reacionais brandas, a 80 °C em pressão atmosférica, caracterizando um sistema verde. As variações na concentração inicial de reagentes a fim de entender o sistema foram estudadas, o que direcionou o estudo para sua otimização via planejamento de experimentos, sendo atingida uma conversão de 100 % em 10 h de reação. A obtenção de limoneno por evaporação de passo curto do óleo de laranja também foi estudada e otimizada, chegando-se à pureza de 99,6 %. O ensaio nas condições ótimas de reação com o limoneno obtido do óleo de laranja mostrou-se idêntico ao limoneno comercial. Os resultados obtidos demonstram a eficácia tanto do processo de obtenção do limoneno, como do sistema reacional com uma produção limpa, uma característica imprescindível para biofabricação
Abstract: One of the most important olefins from a renewable source of in Brazil is limonene. The orange peel oil is about 90% limonene. Brazil is the largest producer of orange in the world wild, with a 2010-2011 production about 15.33 million tons of fruit. About 89% of the fruits are intended for the production of juice, which peel and fixed oil are residue from the process. The volatile oil portion is composed predominantly of (R)-limonene. Terpenes such as limonene, may be subjected to catalytic oxidation reactions where the epoxides are the main products, and can be used as precursors for a wide variety of products such as pharmaceuticals, fragrances and the manufacture of biopolymers and resins. By the above, this work is dedicated to study the epoxidation of limonene in order to obtaining epoxides that may be used as monomers for the synthesis of biomaterials with chemical quality to medical devices manufacturing. Thus, some systems like methyltrioxorhenium, montmorillonite and alumina were tested. The most promissory system, using H2O2 as oxidant, ?-Al2O3 as catalyst and ethyl acetate as solvent, was evaluated in mild reaction conditions, at 80 °C at atmospheric pressure, featuring a green system. It was carried out the initial concentration of the substrate, oxidant and catalyst variation studies in order to understand the system, which directed for the optimization by experimental design. It was achieved a 100% of conversion in 10 hours of reaction. It was also studied the limonene purification by short path evaporation of the orange oil. It was achieved a limonene with 99.6 % of purity. The optimum reaction conditions were performed with limonene obtained from orange oil, the comparative result showed and an identical behavior between the commercial and the distillated limonene. These results demonstrate the effectiveness of both the process, the limonene obtainment and the reaction system with a clean and no toxic production, an essential feature for biofabrication
Mestrado
Desenvolvimento de Processos Químicos
Mestre em Engenharia Química

No processo de obtenção de níquel de fontes de minério limonita, a lixiviação ácida do minério resulta na dissolução de íons metálicos em uma solução aquosa. Com o uso da tecnologia apropriada, é possível recuperar esses íons metálicos em vez de descartá-los. O presente estudo tem como objetivo a recuperação de magnésio de uma solução contendo íons magnésio e sulfato utilizando-se a técnica da cristalização a alta temperatura. A aplicação da cristalização a alta temperatura para recuperar o magnésio na forma de sulfato de magnésio hidratado pode ser vantajosa uma vez que sua decomposição térmica resulta em MgO e SO2, produtos que podem ser reutilizados no processo de mineração da limonita. Isso reduz o volume de resíduo formado e custo de reagentes no processo. Foi projetado um sistema de cristalizador acoplado a filtração e foi verificado a influência da temperatura, tempo de residência e pH da solução na quantidade de magnésio cristalizado. A solução residual de cada batelada foi analisada por cromatografia de íons para quantificar o magnésio na solução. Os cristais formados foram analisados utilizando-se a técnica de difração de raios-X (DRX), por microscopia eletrônica de varredura (MEV-EDS) e agitamento de peneiras a fim de avaliar a composição química, morfologia e granulometria dos cristais. A solubilidade do sulfato de magnésio foi determinada experimentalmente com o intuito de ampliar a compreensão da solubilidade do sal e obter valores de Kps. Em 5 horas de tempo de residência o sistema foi estabilizado, indicando que não haverá mais crescimento cristalino em tempos de residência maiores que 5 horas. Em pH 5,7 a 230°C e em 5 horas de tempo de residência ocorreu a maior remoção de magnésio com cerca de 81% cristalizado. Os cristais apresentaram morfologia esférica com exceção do cristal obtido a 230 °C em pH 2, que apresentou formato retangular. A análise por DRX mostrou a presença de um produto constituído majoritariamente por sulfato de magnésio monohidratado.
In the process of obtaining nickel from sources of limonite ore, the acid leaching of the ore results in the dissolution of metallic ions in solution. With the use of appropriate technology, it is possible to recover these metal ions instead of discarding them. The present study aims to recover magnesium from a solution containing magnesium and sulfate ions using high temperature crystallization. The application of high temperature crystallization to recover magnesium in the form of hydrated magnesium sulfate may be advantageous since its thermal decomposition results in MgO and SO2, products which can be reused in the limonite mining process. This reduces the volume of waste formed and the cost of reagents in the process. A crystallizer coupled to a filtration system was designed and the influence of the temperature, residence time and pH of the solution on the amount of crystallized magnesium from solution was investigated. The residual solution was analyzed by ion chromatography to quantify the magnesium in the solution. The crystals formed were analyzed by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM-EDS) and sieve shakers in order to evaluate the chemical composition, morphology and grain size of the crystals. The solubility of magnesium sulphate was determined experimentally to increase the understanding of the solubility of the salt and obtain values of Kps. In 5 hours of residence time the system was stabilized, indicating that there will be no more crystalline growth at residence times greater than 5 hours. At pH 5.7 at 230 ° C and in 5 hours of residence time 81% of Mg crystallized. The crystals presented spherical morphology except for crystals obtained at 230 °C, at pH 2, which presented a rectangular shape. XRD analysis showed the presence of a product consisting mainly of magnesium sulphate monohydrate.

Orientador: Glaucia Maria Pastore
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: O objetivo do presente trabalho foi efetuar estudos de biotransformação de substratos terpênicos para a obtenção de compostos de aromas naturais, ou bioaromas, enfatizando os processos bioquímicos envolvidos nos procedimentos empregados e a otimização da produção para possíveis aplicações industriais. Assim, o estudo se iniciou com o isolamento de quase 300 linhagens, das quais 121 mostraram-se resistentes a concentrações de 2% de R-(+)-limoneno e 70 foram capazes de utilizar este substrato como única fonte de carbono. Dentre todas as linhagens potencialmente degradantes do R-(+)-limoneno, nenhuma mostrou acúmulo significativo de metabólito de interesse em concentrações que justificassem estudos de otimização. A seguir, o método de Superfície de Resposta foi empregado para otimizar os principais parâmetros do processo de produção de R-(+)-a-terpineol a partir do R-(+)-limoneno pelo fungo Fusarium oxysporum 152b. Dentre os 10 parâmetros analisados (concentração de glicose, peptona, extrato de malte e de levedura no meio de biotransformação; concentração de R-(+)- limoneno; concentração de biosurfactantes; temperatura; agitação; pH; tamanho do inóculo), três (concentração de substrato, temperatura e agitação) influenciaram significativamente (p < 0,10) a produção de R-(+)-a-terpineol, dentro das faixas estudadas. A otimização dessas variáveis por um Delineamento Composto Central Rotacional revelou que as condições ótimas para a biotransformação foram de 0,5% de R-(+)-limoneno, 26 °C e 240 rpm, resultando em uma concentração de cerca de 2,4 g.L-1 de R-(+)-a-terpineol ao final de 72 h de processo. Aproveitando-se do fato de essa linhagem fúngica ser reconhecida pela produção de lípase alcalina, um sistema integrado de produção foi posteriormente proposto a fim de explorar todo potencial biotecnológico do microrganismo. Assim, a biomassa resultante da produção de lipase, antes descartada, foi avaliada quanto à preservação da atividade de biotransformar o R-(+)- limoneno. Os resultados demonstraram ser possível a coprodução de lipase/R-(+)-a-terpineol, apesar de que o rendimento máximo do bioaroma foi cerca de 50% inferior quando comparado ao do procedimento convencional. Os estudos com duas linhagens bacterianas (Pseudomonas rhodesiae CIP 107491 e P. fluorescens NCIMB 11671) para a bioconversão de alguns monoterpenos indicaram a presença de uma via metabólica envolvendo ß-pineno, a-pineno, a-pineno oxido, isonovalal e ácido dimetil pentanóico para ambas espécies, além de outras duas vias de degradação do limoneno para P. fluorescens. Nesse caso, a bactéria usava o limoneno como única fonte de carbono e energia, passando por limoneno-1,2-diol, e também hidroxilava este substrato na posição 8 formando R-(+)-a-terpineol como forma de diminuir a toxicidade do substrato (metabolismo de xenobióticos). Essa última via ocorria em ausência de cofatores graças à ação de uma hidratase enantioespecífica capaz de converter anaerobicamente R-(+)-limoneno a R-(+)-a-terpineol e S-(¿)-limoneno a S-(¿)-a-terpineol em meios bifásicos, empregando n-hexadecano como fase orgânica. Foi posteriormente demonstrado que os rendimentos e produtividade poderiam ser significativamente elevados e que a produção poderia ser mais que duplicada (de ~10 para ~25 g.L-1) com o uso de fases orgânicas não convencionais, como óleos vegetais. Finalmente, estudos preliminares de avaliação do potencial bioativo do principal produto relatado nessa tese demonstraram que o a-terpineol revelou uma elevada capacidade de absorção de radical de oxigênio (ORAC) e atividade antiploriferativa contra cinco linhagens de células cancerosas, apesar da baixa atividade de captura de radical DPPH. Esses resultados abrem precedentes para que pesquisas in vivo sejam consideradas a fim de determinar o potencial funcional desse bioaroma, algo ainda praticamente inexplorado
Abstract: The objective of the present work was to study the biotransformation of terpene substrates to obtain natural flavor compounds (bioflavors), focusing the biochemical processes involved in the procedures investigated and optimization of production for possible industrial applications. Therefore, the study started with the isolation of more than 300 wild strains followed by the selection of 121 capable of resisting to 2% (v.v-1) of R-(+)-limonene and 70 that could use this terpene as sole carbon and energy source. None of the strains tested showed accumulation of intermediate metabolites in levels that justified further optimization studies. Subsequently, the Response Surface Methodology was employed to optimize the main parameters of the process of biotransformation of R-(+)-limonene to R-(+)-a-terpineol by the fungal strain Fusarium oxysporum 152b. Only three (R-(+)-limonene concentration, temperature and agitation) of the ten parameters tested (concentration of glucose, peptone, malt extract and yeast extract; substrate concentration; biosurfactant concentration; temperature; agitation; pH; inoculum size) influenced significantly (p < 0.1) the R-(+)-a-terpineol production. The optimization of these variables applying a Central Composite Design revealed that the optimal biotrasformation conditions were 0.5% of R-(+)-limonene, 26 °C and 240 rpm, resulting in a R- (+)-a-terpineol concentration close to 2,4 g.L-1 after a 72 h. Since this fungus has been recognized for its high alkaline lipase production, an integrated process was proposed to explore the full biotechnological potential of this microorganism. Therefore, the biomass resulting from the lipase production, which was previously discharded, was tested to evaluate the preservation of R-(+)-limonene-biotransformation activity. The results have shown that the co-production of lipase/R-(+)-a-terpineol was feasible, although the maximal yield of the bioflavor was approximately 50 % lower when compared to the conventional process. The studies with two pseudomonad strains (Pseudomonas rhodesiae CIP 107491 e P. fluorescens NCIMB 11671) for the conversion of some monoterpenes indicated the presence of one metabolic route involving ß-pinene a-pinene a-pinene oxide, isonovalal and dimethyl pentanoic acid for both species, besides two other pathways for the degradation of limonene by P. fluorescens. In this case, the bacterium used the substrate as sole carbon and energy source, with limonene-1,2-diol as intermediate, and also hydroxylated limonene in the position 8 to R-(+)-a- terpineol as a detoxifying strategy (xenobiotic metabolism). The last pathway occurred in the absence of cofactors due to the action of an enantiospecific hydratase capable of converting anaerobically R-(+)-limonene to R-(+)-a-terpineol and S-(¿)-limonene to S-(¿)-a-terpineol in biphasic mediums, employing n-hexadecane as organic phase. It was later demonstrated that the yields and productivities could be significantly enhanced and that the final concentration of the product could be more than duplicated (from ~10 to ~25 g.L-1) if unconventional organic phases (vegetable oils) were used. Finally, preliminary studies evaluating the bioactive potential of the main product reported in this thesis have revealed that the a-terpineol demonstrated an oxygen radical absorbance capacity (ORAC) and an antiproliferative activity against five cancer lines, although the DPPH radical scavenging activity was low. These results encourages in vivo research to determine the functional potential of this bioflavor, something practically unexplored
Doutorado
Doutor em Ciência de Alimentos

In this thesis, we explored the use of a renewable resource to produce more sustainable polymeric materials. Limonene, a monocyclic terpene existing in many essential oils extracted from citrus rinds, was the renewable monomer investigated. The d-limonene ((+)-limonene) isomer is a major component (~90%) of orange oils from orange juicing and peel processing. Having been used as a flavour and fragrance additive in cosmetics, foods and beverages, as well as a green solvent, limonene is of particular interest in polymerization, because it contains double bonds, which provide the bifunctionality necessary for polymerization. Limonene is also an allylic monomer (CH2=CH-CH2Y), which presents challenges in free-radical homopolymerization and thus, copolymerization was investigated herein to overcome this difficulty. 2-Ethylhexyl acrylate (EHA) and n-butyl methacrylate (BMA) were used in two separate projects, as comonomers with limonene. Using bulk free-radical copolymerization at 80℃, with benzoyl peroxide (BPO) as the initiator, high molecular weight (>100,000) EHA/limonene and BMA/limonene copolymers were produced. Reactivity ratios, important parameters used in the prediction of copolymer composition, were estimated and shown to accurately predict the copolymer composition of subsequent experiments. These can now be used for the application of appropriate semi-batch policies to further enhance limonene incorporation into the copolymers.

Le limonène a été souligné comme molécule clé pour le développement de polymères biosourcés comme alternative aux monomères classiques provenant de sources pétrolières, mais la polymérisation directe de celui-ci conduit à des plastiques de basse qualité. Cependant, ses produits d’époxydation tels que le 1,2-oxyde de limonène et le dioxyde de limonène sont essentiels pour la production de polycarbonates verts et de polyuréthanes sans l’utilisation d’isocyanate et par conséquent la production de ces deux molécules devient un enjeu majeur. Tout d’abord, l’époxydation du limonène a été effectuée en présence d’un catalyseur au titane de basse coordination supporté sur une silice mésoporeuse de type SBA-16 en présence de TBHP dans le décane comme agent oxydant. La conversion en limonène a été de 80% avec une sélectivité en 1,2-oxyde de limonène de 79% ainsi que de 21% en 8,9-oxyde de limonène après 24 h de temps de réaction. Les conditions réactionnelles ont été optimisées et la réaction doit être effectuée en présence de 300 mg du catalyseur à 75oC dans l’acétonitrile comme solvant avec un rapport molaire TBHP/limonène de 11/6,2. Toutefois, l’utilisation d’un catalyseur au titane supporté sur une silice mésoporeuse s'est avérée inefficace pour la double époxydation du limonène en dioxyde de limonène. Différentes alternatives ont été considérées afin de produire cette molécule. Une approche relativement verte consiste à effectuer la double époxyadtion dans des conditions semi-continues en employant le DMDO généré in situ par la réaction de l’acétone avec une solution aqueuse d’Oxone® à température ambiante. Deux méthodes ont été étudiées et comparées. Tout d’abord la réaction a été effectuée dans un système biphasique conventionnel eau-solvant organique à température ambiante. L’acétate d’éthyle a été employé comme phase organique dans cette étude. La conversion obtenue dans ces conditions a été de 95% avec un rendement de 33% pour le dioxyde de limonène. Lorsque cette même réaction a été effectuée en excès d’acétone, la conversion obtenue a été de 100% et un rendement de 97% en dioxyde de limonène en seulement 1,5h. Les conditions de la réaction ont été optimisées. La réaction doit être effectuée avec un débit de solution aqueuse d’Oxone® de 4 mL min-1 et un excès stoechiométrique de 33% avec un temps de réaction de 45 min à température ambiante. Le caractère multiphasique de la réaction d’époxydation du limonène entraîne des limitations du transfert de matière du DMDO de la phase aqueuse à la phase acétone. Pour pallier ce problème, les ultrasons ont été employés afin d’accélérer ce processus de transfert de matière et réduire le temps de la réaction. La double époxydation du limonène en présence d’ultrasons avec une puissance nominale de 50W a permis d’obtenir un rendement de 100% en dioxyde de limonène avec un temps de réaction de seulement 4,5 min à température ambiante. À partir de ces résultats, d’autres terpènes ont aussi été époxydés afin de généraliser la technique. Les deux isomères du pinène ont été convertis à 100% en leur époxyde respectif en seulement 4 min. Le farnésol, un tri-alcène, a lui été converti à 100% en tri-époxyde de farnésol en 8 min. Le carvéol, un dérivé du limonène a été converti à 100% après 5 min de temps de réaction. Le rendement en diépoxyde était supérieur à 95%. Les sous-produits de la réaction consistaient aux deux monoépoxydes du carvéol et la présence de carvone a aussi été détectée. Le carvone, un autre dérivé du limonène a lui aussi été converti à 100% après 5 min de temps de réaction, seulement le 7,8-époxyde carvone, un monoépoxyde, a été produit
Limonene has been highlighted as a key molecule for the development of bio-based polymers as an alternative to conventional monomers from petroleum sources, but the direct polymerization of this leads to low quality plastics. However, its epoxidation products such as 1,2-limonene oxide and limonene dioxide are essential to produce green polycarbonates and polyurethanes without the use of isocyanate, therefore the production of these two molecules becomes a major issue. First, the epoxidation of limonene was carried out using low coordination titanium catalyst supported on a SBA-16 mesoporous silica in the presence of TBHP in the decane as oxidizing agent. The conversion to limonene was 80% with a selectivity of 79% 1,2-oxide of limonene and 21% of 8,9-limonene oxide after 24 hours of reaction time. The reaction conditions were optimized, and the reaction should be carried out in the presence of 300 mg of the catalyst at 75 ° C in acetonitrile as solvent with a molar ratio TBHP / limonene of 11 / 6.2. However, the use of a titanium catalyst supported on a mesoporous silica has proved ineffective for the double epoxidation of limonene to limonene dioxide. Different alternatives have been considered in order to produce this molecule. A relatively green approach is to perform the double epoxydation under semi-continuous conditions using DMDO generated in situ by the reaction of acetone with an aqueous solution of Oxone® at room temperature. Two methods have been studied and compared. First, the reaction was carried out in a conventional biphasic water-organic solvent system phase at room temperature. Ethyl acetate was used as the organic phase. The conversion obtained under these conditions was 95% with a yield of 33% for limonene dioxide. When the same reaction was carried out in excess of acetone, the obtained conversion of limonene was 100% leading to 97% of limonene dioxide in only 1.5 hours. The conditions of the reaction have been optimized. The reaction must be carried out with a flow rate of Oxone® aqueous solution of 4 mL min-1 and a stoichiometric excess of 33% with a reaction time of 45 min at room temperature. On the other hand, the multiphasic nature of this reaction causes limitations in the mass transfer of DMDO from the aqueous phase to the acetone phase. Ultrasound has been used to accelerate the mass transfer. process of DMDO and thereby reduce the reaction time. The double epoxidation of limonene in the presence of ultrasound with a nominal power of 50W achieved a yield of 100% of limonene dioxide with a reaction time of only 4.5 min at room temperature. From these results, other terpenes have also been epoxidized to generalize the technique. Both isomers of pinene were converted to 100% in their respective epoxide in just 4 min. Farnesol, a tri-alkene, has been converted to 100% farnesol tri-epoxide in 8 min. Carveol, a derivative of limonene was converted to 100% after 5 min of reaction time. The diepoxide yield was higher than 95%. The by-products of the reaction consisted of both carveol monoepoxide and the presence of carvone was also detected. Carvone, another derivative of limonene, was also converted to 100% after 5 min of reaction time. Only 7,8-epoxide carvone, a monoepoxide, was produced.

Orientador: Everson Alves Miranda
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
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Resumo: As indústrias cítricas geram grandes quantidades de efluentes líquidos. Estes efluentes são potencialmente poluidores para descarte em corpos d'água e necessitam de tratamento adequado. A maioria das plantas de tratamento de efluentes cítricos utiliza processos biológicos, devido a custos operacionais mais baixos quando comparado aos processos físico-químicos. Porém, estas plantas têm apresentado problemas de eficiência de remoção da carga orgânica e inibição da atividade biológica, em função das características tóxicas do efluente cítrico, devido à presença residual do d-limoneno, um monoterpeno extraído da casca da laranja. O d-limoneno, quando separado e purificado, tem ampla aplicação industrial, na área cosmética como fragrância e na área alimentícia como agente antimicrobiano e também pode ser bioconvertido em produtos como ácidos e alcoóis perílicos e carvona que podem ser utilizados na terapia do câncer. Os objetivos deste estudo foram selecionar e identificar microrganismos capazes de degradar o d-limoneno em altas concentrações (até 5%), simulando condições similares aos efluentes cítricos e avaliar o comportamento de consórcio destes microrganismos. Também foi avaliada a qualificação dos produtos obtidos da bioconversão do d-limoneno. Os microrganismos foram isolados a partir do lodo ativado de uma estação de tratamento de esgotos. Uma pré-seleção, de 56 linhagens de bactérias foi realizada, durante as 3 etapas de enriquecimento com o d-limoneno, através da técnica de esgotamento em superfície. Foram selecionadas 10 linhagens, que apresentaram maior crescimento visual, que foram caracterizados através da morfologia, coloração diferencial (Gram) e análise filogenética. A biodegradação do d-limoneno foi avaliada pela remoção de DQO em meios de cultivos diferentes variando as concentrações de d-limoneno (1%, 3% e 5%) sob condição agitada e estática na temperatura de 30°C. A bioconversão dos produtos foi qualificada por cromatografia gasosa. Foram isoladas bactérias Gram-positivas, do gênero Bacillus resistentes à concentração de 5% de d-limoneno sem fonte complementar de carbono. A remoção de DQO foi de 77% e terpineol, alcoóis ciclodecanol e octanediol foram qualificados como produtos bioconvertidos
Abstract: The citrus' industries generate large quantities of wastewater. These effluents are potentially polluting to disposal in water bodies and require treatment. Most sewage treatment plants citrus use biological process due to lower operating costs compared to physical-chemical processes. However these plants have presented problems in the efficiency removal of organic charge and inhibition of the biological activity due to citric toxic characteristics because of the presence of residual d-limonene, a monoterpene extracted from orange peel. The d-limonene, when it is separated and purified, has large industrial application, on field cosmetics as fragrances and foods fields as antimicrobial agent. Besides, the d-limonene can be bioconverted in perillic acids and perillyl alcohol, ?-terpineol and carvone that can be used in cancer therapy. The achievement of this study was select and isolate microorganism able to degradation high containing limonene (since 5%), simulating the same condition of wastewater characterizes of citric plants and evaluated the consortium microorganism behavior. In addition, the products of biotransformation d-limonene were qualified. Microorganisms were isolated from activated sludge of sewage treatment plant. A pre-selection, with 56 strains, was undertaken, during the 3 stage of enrichment with d-limonene, using depletion technique to isolate microorganisms. Ten strains were selected that showed the greater visual growth. They were characterized through of morphology, Gram and phylogenetic analysis. The d-limonene biodegradation was determinate by reduction COD in different cultivation media, varying the concentration of d-limonene (5 %, 3 % and 1 %) in agitated and stationary condition at temperature 30°C. The bioconversion of product obtained was confirmed by gas chromatography. Gram-positive bacteria were isolated of the Bacillus genus, bacteria resist to 5% of limonene-containing without complementary source of carbon. The removal of COD was 77% and terpineol, cyclodecanol and octadienol was evaluated as products bioconverted
Mestrado
Desenvolvimento de Processos Biotecnologicos
Mestra em Engenharia Química

Today, the scenario of the world and brazilian energy matrix is of great difficulty, due to increased demand for fossil fuels causing instabilities in prices and in the fuel sector, as well as serious environmental risks to the whole population. The difficult time comes driving the search for new sources of renewable and clean energy such as biogas. In this way, this work aimed to evaluate the anaerobic biodigestion from the residue of agro-industry of citrus using inoculum from swine waste water. We used 12 anaerobic batch type reactors, fed with different concentrations of residues of citrus being inoculated with the swine waste. Were testadas4 citrus residue concentrations (25%, 50%, 75% and 100%) during 60 days. It was observed that the increase in the concentration of residues of citrus caused a decrease in pH and metanogênica activity specifies fact that can be assigned inhibiting substance (D-Limonene) present in citrus peel, which when not undergo a pre-treatment can negatively affect the work of metanogênicas microorganisms. However, the proportion of 25% of citrus residue with 10% p.10536–10540 of swine waste for better production of methane when no pre-treatment of the citrus.
Nos dias atuais, o cenário da matriz energética mundial e brasileira é de grande dificuldade, devido ao aumento da demanda pelos combustíveis fosseis o que causa instabilidades nos preços e no setor dos combustíveis, além de sérios riscos ambientais a toda população. O momento difícil vem impulsionando a procura por novas fontes de energia renováveis e limpas, como o biogás. Desta forma, este trabalho teve como objetivo avaliar a biodigestão anaeróbia a partir do resíduo da agroindústria do citrus utilizando como inóculo a água residual da suinocultura. Foram utilizados 12 reatores anaeróbios tipo batelada, alimentados com diferentes concentrações de resíduos de citrus sendo inoculadas com dejetos da suinocultura. Foram testadas4 concentrações de resíduo de citrus (25%, 50%, 75% e 100%) durante 60 dias. Foi observado que o aumento da concentração de resíduos de citrus causou uma diminuição do pH e, conseqüentemente atividade metanogênica especifica fato que pode ser atribuído a substância inibidora (D-limoneno) presente na casca do citrus, que quando não passam por um pré-tratamento podem afetar negativamente os trabalhos dos microorganismos metanogênicas. Entretanto, sugere-se a proporção de 25% de resíduo de citrus com 10% de inoculo de dejetos suínos para uma melhor produção de metano quando não houver pré-tratamento do citrus.

Ziel des Forschungsvorhabens war die Untersuchung von Möglichkeiten zur Intensivierung des mikrobiellen Abbaus des Geruchsstoffes Limonen unter Anwendung des Biofilter-verfahrens. Limonen stellt eine wesentliche Geruchskomponente bei der Intensivrotte der Bioabfallkompostierung dar und wird bisher in biologischen Abluftreinigungsanlagen oft nur unzureichend eliminiert. Dies führt zu einer Geruchsbelästigung des Personals und an-grenzender Wohngebiete. Die Verbesserung des hygienischen Status der Bioabfallkom-postierung und eine damit verbundene Steigerung ihrer gesellschaftlichen Akzeptanz erfordert daher ein Biofilterverfahren, das hinsichtlich des Limonenabbaus optimiert wird. Die Zuverlässigkeit von Biofiltern ist neben der Einstellung und Optimierung technischer Parameter auch von der biologischen Aktivität der im Strukturmaterial vorhandenen Mikro-organismenbiozönose abhängig. Viele zum mikrobiellen Abbau von Limonen befähigte Mikroorganismen sind zwar bekannt, doch handelt es sich bei den beschriebenen Abbau-mechanismen hauptsächlich um eine unvollständige Mineralisierung dieses Geruchsstoffes, die zu einer Anreicherung wiederum geruchsbelasteter Verbindungen führt. In dieser Arbeit wurden aus Umweltproben (Fichtenzapfen, -nadeln, -rinde; Waldboden; Schalen von Zitrusfrüchten; Bioabfall) vier bakterielle Mischpopulationen, die zur Ver-wertung von Limonen als einzige Energie- und Kohlenstoffquelle in der Lage sind und durch Wachstum auf diesem Substrat Biomasse bilden, in Schüttelkultur durch Metabolisierung von Limonen erfolgreich angereichert. Hinsichtlich ihrer Abbaukinetik für Limonen wiesen alle Batch-Kulturen eine starke Ähnlichkeit auf. Limonen wurde bei Anfangskonzentrationen von 536,5-889,5 mg/l nach 41-59 Stunden und mittleren Abbauraten von 48,1-51,0 mgl-1h-1 durch die Batch-Kulturen bis unter die Nachweisgrenze abgebaut. Nach erfolgter Degradation hinterließen die Proben einen neutralen Geruchseindruck. Eine Akkumulation von Metabo-liten oder Endprodukten konnte gaschromatographisch nicht nachgewiesen werden, was auf einen vollständigen Limonenabbau hindeutet. Substratkonzentrationen von > 4042 mg/l führten dagegen zu einer Inhibierung des Limonenabbaus und zu einer Stagnation des Wachstums bzw. zum Absterben der Bakterien in den Schüttelkulturen. Die mikrobiologische Grobcharakterisierung führte zur Isolierung von insgesamt 44 Reinkulturen, die einzeln auf Limonenabbau getestet wurden. Es gelang, sechs Bakterien-stämme zu isolieren, die in der Lage waren, Limonen ohne Akkumulation geruchsintensiver Intermediärverbindungen abzubauen. Mittels physiologisch-biochemischer sowie chemotaxo-nomischer Untersuchungen wurden die Bakterienisolate vorbehaltlich der Nachfolgeunter-suchungen der Gattung Pseudomonas zugeordnet. Die molekularbiologische Untersuchung mittels Proteingel-Elektrophorese ergab durch Vergleich einzelner Proteinbanden im Gesamt-zellproteinmuster der Isolate untereinander sowie mit Referenzstämmen die Identität der Isolate L1,2, L2,4 und L4,10. Isolat L2,6 wies deutliche Unterschiede im Proteinbandenprofil gegenüber den übrigen Isolaten und Referenzstämmen auf und wurde zum Vergleich der Isolate L3,6 und L3,8 zu einer 16S rRNA Teilsequenzanalyse herangezogen. Die vollständige Sequenzanalyse des Isolates L3,6 führte zu einer Identität von 97 % mit P. alcaligenes. Hier muß davon ausgegangen werden, daß es sich um eine neue bisher nicht beschriebene Spezies der Gattung Pseudomonas handelt. Isolat L2,6 zeigte in der Teilsequenzanalyse eine Über-einstimmung von 96 % mit P. mendocina, was für die Zugehörigkeit zu einem neuen Genus spricht. Der Vergleich der Teilsequenzen von Isolat L3,8 mit denen bekannter Spezies ergab eine Identität von 98 % mit Pseudomonas sp. B13. Die endgültige taxonomische Einordnung ist allerdings erst nach einem Sequenzvergleich durch DNA-DNA-Hybridisierungen mit bisher sequenzierten Spezies möglich. Die Limonen-abbauenden Bakterienstämme L2,6, L3,6 und L3,8 repräsentieren daher eindeutig verschiedene Spezies, die vorläufig dem Genus Pseudomonas zugeordnet wurden. Die Wirksamkeit der Strategie, den Limonenabbau im Biofilter durch den Einsatz einer leistungsfähigen Anreicherungskultur (Mix der vier Anreicherungskulturen) zu verbessern, wurde im Überführungsversuch in zwei parallel laufenden Modellbiofiltern gaschromato-graphisch untersucht. Aus dem inokulierten Biofilter wurden Wirkungsgrade bis zu 100 % nach 67 Tagen Laufzeit bei kaum geänderter Gesamtkeimzahl ermittelt. Auch nach Einstellung der Beimpfung betrug die Konzentrationsminderung für Limonen bis zu 89 %. Die Einlaufphase des inokulierten Biofilters konnte gegenüber einem konventionellen Biofilter um 46 Tage auf 35 Tage wirksam verkürzt werden. Eine mikrobiologische Charakterisierung der aus zwei Biofiltern isolierten Bakterienkulturen ergab nicht die erwar-teten Unterschiede hinsichtlich der mikrobiologischen Besiedelung des Filtermaterials beider Biofilter. Die Wirksamkeit der Inokulationskulturen im Biofilter ließ sich gaschroma-tographisch und olfaktometrisch anhand der eliminierten Limonen- oder Geruchsstoffkon-zentrationen eindeutig nachweisen. Die Unterschiede in den Abbauleistungen beider Biofilter widerspiegeln sich folglich nicht deutlich in den taxonomischen Merkmalen der Bakterien-biozönosen. Vielmehr ist die mit der Ausbildung spezieller Enzymsysteme verbundene physiologische Adaptation verschiedenster Bakterienspezies entscheidend, um eine Opti-mierung des mikrobiellen Abbaus von Limonen in Biofiltern zu erreichen
This study aimed to investigate the opportunities for the intensification of the microbial biodegradation of the odourous compound limonene by biofiltration as a biological waste gas treatment technology. Limonen represents a considerable odourous component during the intensive composting process of organic waste materials and its elemination capacity by using the biological waste gas treatment facilities is so far insufficient. This results to a molestation of the staff of composting facilities and adjacent residential areas by odours. The improvement of the hygienic status of the composting process connected with the increase of their social acceptance requires a biofilter system which is to be optimized regarding the biodegradation of limonene. The reliability of such biological deodorizing methods depends on the adjustment and optimisation of technological parameter as well as on the biological activity of limonene metabolizing microorganism microbiota in the carrier material. Though a wide range of limonene utilizing microorganisms are known, but the described bioconversion processes deal with mainly incomplete mineralization of these odourous compound resulting again in an accumulation of further volatile odourous substances. In this study four mixed bacterial population were successfully obtained from organic material samples (fir cone, fir needles, fir bark; coniferous forest soil; parings from citrus fruits; bio waste) by a simple enrichment technique (semicontinuous fed-batch principle) using limonene as the sole carbon and energy source, accompanied by microbial growth and mineralization. In consideration of the degradation kinetics of limonene all of the batch-cultures have shown high similarity. By initial concentrations of 536,5-889,5 mg/l after 41-59 hours and middle degradation rates of 48,1-51,0 mgl-1h-1limonene was degraded by bacterial cultures under the detection limit and samples have had a more neutral odourous impression. An accumulation of metabolites and other final products couldn't be detected by gaschromatography and this indicates a complete limonene bioconversion. Substrate concentrations greater than 4042 mg/l inhibited outright the biodegradation of this odourous compound as well as the growth of these bacteria and entailed finally to a toxic effect of the cells. Through microbial characterization 44 aerobic pure strains were isolated which were individually tested on limonene degradation. The isolation of six bacteria strains that were capable of limonene degradation without accumulation of other intermediate odourous compounds were achieved. Physiological, biochemical as well as chemotaxonomic characterization tests assigned the bacterial isolates subject to additional tests to the genus Pseudomonas. Phylogenetic investigation by using polyacrylamid gel electrophoresis revealed through comparison of the several protein bands in the whole protein pattern of the isolates with each other as well as with reference strains the identity of the isolates L1,2, L2,4 and L4,10. The isolate L2,6 showed clear differences in the protein pattern to the other isolates and reference strains and was taken with regard to a comparison of the isolates L3,6 and L3,8 to a partial 16S rRNA sequence analysis. The complete 16S rRNA analysis of the isolate L3,6 led to an identity of 97 % with P. alcaligenes. It has to be assumed here that the isolate is different from species previously described and represents a new species of the genus Pseudomonas. Partial 16S rRNA analysis of the isolate L2,6 showed a similarity of 96 % between the isolate and P. mendocina and indicate that this isolate is a member of a new genus. Partial 16S rRNA sequence comparison of the isolate L3,8 with corresponding fragments from reference strains listed in the data bank of nucleotides resulted in a similarity of 97 % with Pseudomonas sp. B13. For the definitive taxonomic arrangement of these isolates DNA-DNA hybridization with related species are required. The limonene degrading isolates represent clearly different species provisionaly allocated to the genus Pseudomonas. The effectiveness of the strategy to enhance the removal capacity for limonene with an efficient enrichment culture (mix of the four batch cultures) was tested in two parallel running biofilters (one inoculated and one biofilter without inoculation) and the degradation of limonene was followed. Chemical analysis was carried out by gas chromatography mass spectrometry. From the inoculated biofilter an efficiency up to 100 % was determined after 67 days running time and the total cell count altered scarcely. Also after a discontinue of the inoculation the elimination capacity for limonene amounted up to 89 %. The adaption time of the inoculated biofilter was successfully reduced from 81 to 35 days compared to a conventional biofilter. A microbial characterization of the isolated bacterial cultures from biofilters did'nt show the expected differences concerning the microbial composition of the carrier material of both biofilters. The activity of the enrichment cultures could be clearly proved by gaschromatography and olfactometry by means of the eliminated limonene concentrations. Therefore the differences of the elimination capacity of both biofilters didn't clearly appear in the taxonomic characteristics of the bacterial microbiota. Decisive is rather the physiological adaption of various bacterial species by formation of special enzyme systems to achieve an optimisation of the microbial degradation of limonene in biofilters

Notre objet est de rechercher des signes d'identification d'un pays rural à travers sa chanson traditionnelle, au cours de la première moitié du XXe siècle. Le pays limousin, situé aux contreforts ouest du Massif central français a un sol irrégulier un climat changeant, il est voué à l'élevage. Ne pouvant plus nourrir à cette époque, sa population grandissante, il est, comme d'autres grands pays ruraux européens, le siège de l'émigration. Pays Nord-Occitan, c'est une population éclatée, demeurant fortement attachée à ses racines qui véhicule dans sa mémoire, la langue, les sons, les rythmes supportant la tradition, les usages et par suite les chansons du pays, transmises jusqu'alors de bouches à oreilles. Quels sont les signes souvent très ténus mais non moins solides qui perdurent jusqu'à travers l'inconscient de ses ressortissants, dans ces pièces "toujours" entendues, qu'on extrait de la mémoire ? Quelle est l'intimité des liens qui se constituent entre la ligne parlée, la ligne chantée et qui se reflète longtemps dans les rythmes et les sons de la langue courante
Our purpose consists in searching identity marks in a rural land through its traditional songs during the first half of the twentieth century. The land of Limousin, part of the west foothills of French Massif Central and devoted to breeding, has an irregular ground and an unstable climate. In the early twentieth century, unable to provide food for its increasing population, Limousin was proned to emigration like many other large european lands. As a North-Occitan country, Limousin is a patchwork of native people, strongly attached to their roots, who bear in their memory, talks, sounds and rhythms, which support traditions, customs and consequently country songs orally relayed till nowadays. What are the marks, tenuous but strong, that remain unconsciously in the mind of the people within these songs, "ever" heard, that one extract from the memory ? What are the links being tied between speaking and singing lines which still stand out in the rhythms and sounds of everyday language ?

Uma possível perda de qualidade dos óleos essenciais pode estar associada à decomposição dos compostos terpênicos, quando submetidos ao aquecimento ou contato com o ar, produzindo odores desagradáveis. A redução do teor dos compostos terpênicos, processo conhecido como desterpenação, pode ser realizada por meio de diversas técnicas. Dentre as inúmeras possibilidades, a extração líquido-líquido tem apresentado resultados bastante promissores. Neste contexto, a presente dissertação de mestrado teve como objetivo a determinação experimental e modelagem do equilíbrio líquido-líquido, a (25,0 ± 0,1) °C, dos sistemas modelo de óleo essencial de bergamota e limão compostos, respectivamente, por: limoneno/ acetato de linalila/ linalol/ etanol/ água e limoneno/ γ- terpineno/ β- pineno/ citral/ etanol/ água. Adicionalmente, as propriedades físicas (viscosidade e densidade) dos sistemas supracitados, bem como dos compostos puros, foram também determinadas. Observou-se que o aumento do teor de água no solvente promoveu uma diminuição da extração do linalol (óleo de bergamota) e citral (óleo de limão), entretanto o maior nível de hidratação do etanol acarretou em aumento da região bifásica e da seletividade do solvente em ambos os sistemas estudados. Os dados experimentais obtidos foram correlacionados utilizando-se os modelos termodinâmicos NRTL e UNIQUAC. Para o sistema de óleo essencial de bergamota, o desvio global obtido foi de 0,43% para o modelo UNIQUAC e 0,52% para o NRTL. No que se refere ao sistema de óleo de limão, a equação NRTL foi a que proporcionou a melhor descrição, apresentando um desvio global de 0,29%, em relação ao modelo UNIQUAC, para o qual o desvio obtido foi de 0,32%. Quanto às propriedades físicas, notou-se que a água não exerce muita influência sobre as propriedades da fase terpênica (fase rica em componentes do óleo essencial); entretanto, na fase solvente observou-se que os valores de densidade e a viscosidade foram aumentados com o aumento do nível de água no etanol.
A possible oil quality loss may be associated to the terpenes compounds decomposition, when heated or exposed to air, producing off -flavors. Terpene partial removal, process known as deterpenation, can be performed using many different techniques. Among these various possibilities, the liquid-liquid extraction has shown successful results. The aim of this work was to determine and correlate the liquid-liquid equilibrium experimental data, using thermodynamic models at (25.0 ± 0.1) ºC for bergamot and lemon essential oils model systems composed respectively of limonene/ linalyl acetate/ linalool/ ethanol/ water and limonene/ γ- terpinene/ β- pinene/ citral/ ethanol/ water. Additionally, physical properties (viscosity and density) of the aforementioned systems and pure compounds were determined. It was observed that the higher water content in the solvent led to a lower linalool (bergamot oil) and citral (lemon oil) extraction. However, the highest level of ethanol hydration enlarged the biphasic region and solvent selectivity for both systems. The experimental data were correlated using the NRTL and UNIQUAC thermodynamic models. For bergamot essential oil system, the global deviation was 0.43% for UNIQUAC and 0.52% for NRTL. The NRTL equation provided a better representation of the lemon oil system, with a global deviation value of 0.29%, compared to the UNIQUAC model with a deviation of 0.32%. It was observed that water does not have a significant effect on the terpene phase (essential oil components rich phase) properties. On the other hand, in the solvent phase, it was observed that a higher water content in the ethanol led to higher density and viscosity values.

Nesse trabalho, foram sintetizados seletivamente, a partir do óxido do limoneno em oposição a diversas aminas primárias e secundárias, onze b-aminoálcoois derivados do limoneno através de aquecimento convencional e sob irradiação com microondas, fornecendo produtos com moderados a bons rendimentos. O limoneno e nove destes aminoálcoois foram testados contra ovos e larvas de carrapatos da espécie de Rhipicephalus (Boophilus) microplusn no intervalo de concentração de 0,150-10mg/mL. Os resultados revelaram que em doses entre 10 μl/ml - 2.5 μl/ml todos os compostos testados foram letais às larvas. Frente ao teste ovicida os compostos 2, 6, 8, 9 e 10 foram os mais ativos, impedindo a eclosão total ou quase total dos ovos na menor dose utilizada (0,150 μg/ml). Este é o primeiro relato da atividade carrapaticida de limoneno, óxido de limoneno e dos b- aminoálcoois do limoneno para a espécie de carrapato Rhipichephalus (Boophilus) microplus. O limoneno e sete β-aminoálcoois foram testatdos in vitro contra forma promastigota de Leishmania (Vianna) braziliensis. Os resultados dos testes mostraram que, dentre os sete β-aminoálcoois testados dois deles foram mais ativos que o padrão pentamidina (48,5 ± 28,7 μM) e cinco foram mais ativos que o limoneno 1. Destes, dois deles (compostos 7 e 9) apresentaram alta atividade frente a formas promastigotas do ciclo parasitário numa concentração de 0,156mg/mL. O Limoneno 1 nesse teste se mostrou inativo (876,2 ± 216 μM) demonstrando que este terpeno isolado não é um bom antiparasitário contra formas promastigotas de Leishmania (Vianna) braziliensis. Este é o primeiro relato de atividade contra leishmania para amino-álcoois derivados do limoneno.
In this work, a series of seven limonene β-amino alcohols derivatives have been regioselectively synthesized from moderate to good yields. The eleven β-amino alcohols Limonene derivatives were synthesized through aminólisis of Limonene oxide, using several primary and secondary amines by both conventional heating and under microwave irradiation. Limonene, Limonene oxide and nine ß-amino alcohol derivatives were investigated for the effect on egg hatchability and mortality rates of newly hatched larvae of cattle tick Rhipicephalus (Boophilus) microplus. At the doses between 10 μl/ml to 2.5 μl/ml all compounds were highly lethal to the larvae and at lower concentrations some of them (2, 6, 8, 9 and 10) showed activity. The effect on hatchbility of the eggs was observed in all treatments. This is the first report of carrapicide activity for Limonene, Limonene oxide and nine ß-amino alcohol derivatives against cattle tick Rhipicephalus (Boophilus) microplus. The leishmanicidal activity was performed and according to the results two of these compounds were more powerful against in vitro cultures of Leishmania (Vianna) braziliensis promastigote form in a range of μM. The activities observed for 3b and 3f were about 100 folds more potent than the drug standard Pentamidine, while the limonene hasn’t shown any activity in the same test. This is the first report of antileishmanial activity of Limonene β-amino alcohol derivatives.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
A reação de transesterificação de óleos vegetais com álcool etílico ou metílico dá origem a ésteres metílicos ou etílicos de ácidos graxos, conhecidos como biodiesel. Este apresenta propriedades próximas do óleo diesel mineral como o número de cetano, massa específica, poder calorífico e relação ar-combustível. Porém, problemas decorrentes de sua maior viscosidade resultam em uma pulverização deficiente pelos bicos injetores levando a uma combustão de qualidade inferior, e com isso, formação de depósitos indesejáveis no interior do motor, alterações nas propriedades do óleo lubrificante e na composição dos gases de escape. Frente a essa questão se faz necessário o estudo da utilização de um aditivo capaz de tornar as características do biodiesel mais adequadas à sua utilização em motores de ignição por compressão e também o acompanhamento das alterações na composição dos gases de escape. O aditivo estudado nesse trabalho foi o d-limoneno, um hidrocarboneto obtido como subproduto da citricultura, que foi adicionado ao óleo diesel à ser utilizado como combustível do conjunto moto-gerador utilizado nos ensaios. Neste sistema foram aplicadas diferentes cargas e coletados os dados relativos à emissão do motor. Resultados relevantes como a redução de material particulados foram observados mesmo com a adição de pequenas quantidades de d-limoneno.
The transesterification of vegetable oils with methanol or ethanol results in methyl esters or ethyl esters of fatty acid, known as biodiesel. This one presents similar features of diesel oil, such as cetane number, specific weight, heat of combustion and air-fuel ratio. However, arising problems from its higher viscosity leads to a poor spraying by the fuel injectors and so to a low-grade combustion, causing formation of undesirable deposits inside the engine, changes in the properties of the lubricating oil and in the composition of the exhaust gas. Owing to this issue, it is necessary to study an additive able to make biodiesel characteristics more appropriate to be used in compression ignition engines, as well as a monitoring of changes in exhaust gas composition. The chosen additive was d-limonene, a hydrocarbon obtained as a byproduct of citriculture, which was added to diesel fuel to be used as fuel for the motor-generator set used in the tests. Different loads were applied to this system and the engine emission data were collected. Relevant results such as the reduction of particulate material were observed even with small amounts of d-limonene added.
CAPES:DS 1600969

La montagne limousine a ete le theatre d'une inversion paysagere exceptionnelle. Ce pays de landes est devenu une region forestiere (la foret occupe plus de la moitie de la surface). Cette "maree verte" imprime dans le paysage le recul de l'agriculture. La foret a une double origine. Sa partie feuillue (le tiers) largement spontanee, colonise lentement la lande. Sa composante resineuse totalement artificielle est de creation recente. Des techniques modernes sont employees pour la mise en place de resineux nobles et pour leur entretien. Ce sont les retombees de cette foret qui ont ete analysees. La montagne, jadis pauvre, va desormais disposer d'une richesse renouvelable. La foret peut-elle etre l'element de revitalisation d'un espace rural tres deprime ? les consequences de cet enresinement sont parfois inattendues. La recolte des cepes est souvent forte, mais la foret paysanne ne s'est pas realisee. Une filiere bois est en train de se mettre en place. Mais la foret permet la concentration de la vie, aussi l'auteur s'est-il interroge sur les rapports entre la foret et les autres activites, tout en proposant de centrer le developpement regional sur une sylviculture de qualite
The limousin mountain is a land of heath which in a few years has been turned into a booming forest area thanks to vast spaces of land given up by agriculture. The deciduous forest which is small is of mediocre quality. On the other end, the evergreen forest is taking advantage of the latest technology. It includes more and more highly productive conifers. The author has tried to study the consequences of this new source of wealth. New jobs related to the forest have been created, from planting to building cutting machines. The output of wood is higher and higher and has become a great asset to the industrialization of the small towns located around the mountain. Ussel is the home of two important triturating mills. Activities strongly tend to concentrate on a few locations so that the interior of the mountain may be turned into a no man's land. In the last part, the writer puts the stress on the connections between the forest and the other activities and he proposes to adjust the development of the area on forestry of high quality

Os óleos essenciais cítricos possuem uma ampla variedade de aplicações em diversos ramos das indústrias químicas, farmacêuticas, de alimentos, entre outras. Na indústria de cosméticos, mais precisamente no ramo de perfumaria, os ativos naturais cítricos (provenientes dos óleos de bergamota, limão, lima, mandarina, laranja, etc) são empregados nas formulações de colônias, cremes hidratantes e loções. Além disso, estes compostos são largamente utilizados como agentes aromatizantes nas indústrias alimentícias e farmacêuticas e empregados como matéria-prima para as indústrias de aromas. Com o objetivo de melhorar a qualidade dos óleos essenciais e sua capacidade aromatizante, alguns processos têm sido desenvolvidos para enriquecer a mistura com compostos oxigenados, os quais são reportados como os principais responsáveis pelo aroma característico da fruta. Tal processo é comumente conhecido como desterpenação e consiste na concentração destes compostos pela retirada de hidrocarbonetos terpênicos do óleo e pode ser realizado por meio da extração líquida ou extração por solvente. Neste contexto, esta dissertação de mestrado teve como finalidade estudar da viabilidade técnica do processo de desterpenação de óleo essencial cítrico modelo composto por limoneno e linalol. Os experimentos foram conduzidos em coluna de discos rotativos perfurados (PRDC) sob condição de temperatura controlada e pressão ambiente local. O equipamento operou de modo contínuo e contracorrente, utilizado como solventes soluções de etanol com teores de água de 30 e 40% (em massa), velocidade de rotação dos discos de 150, 200 e 250 rpm e razão entre a vazão mássica de solvente e alimentação de 0,5; 1,25; 2,5 e 3,0. Avaliou-se, também, o comportamento da densidade e viscosidade das fases extrato e rafinado oriundas da coluna de extração. Através deste estudo foi possível verificar que a tecnologia de desterpenação de óleos essenciais por meio da extração líquido-líquido é viável podendo ser aplicada à processos contínuos utilizando equipamento PRDC, por exemplo, sendo possível a obtenção de frações enriquecidas do composto oxigenado (linalol).
Citrus essential oils are used in a wide variety of applications in various branches of the chemical, pharmaceutical, food and other industries. In the cosmetics industry, specifically in the field of perfumery, natural citrus assets (from the essential oils of bergamot, lemon, lime, mandarin, orange, etc.) are used in the formulations of colonies, moisturizing creams and lotions. Furthermore, these compounds are widely used as flavoring agents in food and pharmaceutical industries and as raw material for the flavor industry. With the aim to improve the quality of essential oils and its flavoring ability, some processes have been developed to enrich the mixture with oxygenated compounds, which are reported as the main responsible for the characteristic aroma of the fruit. Such process is commonly known as deterpenation, and consists in concentration of these compounds by the removal of terpene compounds from the essencial oil and can be performed by liquid or solvent extraction. In this context, the purpose of this dissertation of master\'s degree was to carry out a study of the technical feasibility of deterpenation process of a citrus essential oil model composed by a mixture of limonene and linalool. The experiments of deterpenation were conducted in a perforated rotating discs contactor (PRDC) under controlled conditions of temperature and local environment al pressure. The equipment was operated in continuously and countercurrently mode, using as solvents ethanol solutions with 30 and 40% of water contents (by mass), rotation of discs speed of 150, 200 and 250 rpm and the mass flow rate of the solvent and feed ratio of 0.5, 1.25, 2.5 and 3.0. The behavior of the density and viscosity of the extract and raffinate phases from the extraction column was also evaluated. It was found that the deterpenation of essential oils by liquid-liquid extraction technology is feasible and can be applied to continuous processes using PRDC column extraction type, for instance, being possible to obtain enriched fractions of oxygenated compounds (linalool).

Cette thèse sur "L'héraldique du Limousin du XIIe au XIIe siècle répond à un double objectif. D'une part, recenser toutes les armoiries portées par les familles et les communautés ayant ou ayant eu des liens avec le territoire de la région administrative du Limousin actuel (départements de la Corrèze, de la Creuse et de la Haute-Vienne) entre le XIIe et 2012. Les armoiries des familles ont été prises en compte sans distinction d'origine sociale. Les armoiries des communautés sont celles de collectivités territoriales, associatives, professionnelles et religieuses. Chaque famille et communauté fait l'objet d'une courte notice accompagnée de références notamment bibliographiques. Une table héraldique d'ensemble a été créée. Ce corpus héraldique rassemble au total plus de 5000 armoiries. D'autre part, présenter un certain nombre d'observations et de réflexions sur cette héraldique régionale en distinguant quatre périodes: le Moyen Age, l'époque moderne, le Premier Empire et l'époque contemporaine. Pour chacune de ces périodes, on s'est attaché à faire ressortir les caractéristiques et les originalités de l'héraldique du Limousin. Cette recherche a été complétée par 4 annexes concernant respectivement: la géographie et l'histoire de la région, la cartographie de ce territoire, un document inédit "L'Armorial de Limoges (fin XVIe siècle) et des photographies d'armoiries
This thesis about "The Limousin heraldry from the 12th to 21th century" has a double aim. On one hand, the purpose is to list coats of arms carried by families and communities linked to today's administrative region of Limousin between the 12th and 2012. The families' coats of arms have been considered with no distinction of social background. The communities'coats of arms belong to administrative, associative, professional and religious authorities. For each family and community, there is a short not with some bibliographical references. As a result, a whole heraldic contents is created. This heraldic body of knowledge gathers more than 5000 coats of arms. On the other hand, it consists in presenting a certain number of thoughts about this regional heraldry bringing out four periods: Middle Ages, Modern Time, the First Empire and Contemporary Time. For each period, the main characteristics of Limousin Heraldry are highlighted. Four appendixes complete this research regardin geography and Limousin history, cartography. The "Armorial of Limoges" (16th century unpublished document) and some typical Limousin coats of arms photographs

Afin de comprendre la pollution des eaux en arsenic (As), il est important de connaître les processus biogéochimiques impliqués dans le transfert de ce métalloïde du réservoir solide vers les eaux. Les objectifs étaient d’évaluer (i) la contribution du lessivage des phases solides riches en As, issues d’une anomalie géochimique naturelle, par le biais d’une caractérisation minéralogique et (ii) la mobilisation abiotique et biotique de l’As au cours d’un suivi hydrologique et de tests en laboratoire. Le profil de sol a montré une diminution des teneurs totales en As au cours de la pédogénèse. La caractérisation minéralogique des phases porteuses d’As a montré une évolution dans le profil de sol, des arséniates (pharmacosidérite riche en barium) présents dans la roche mère et la saprolite vers des oxyhydroxydes de fer (goethite, hématite et ferrihydrite) de moins en moins riches en As vers la surface du sol. Le suivi des concentrations en As dissous dans le compartiment aqueux a permis de mettre en évidence les sources de contribution telles les eaux souterraines, les eaux de la zone humide et les eaux de mine à la pollution des eaux de surface. De plus, le suivi in situ de l’As dissous dans les solutions de sol et les eaux de ruissellement a montré un plus fort relargage de ce métalloïde en surface par rapport aux horizons profonds, contribuant également à la composition chimique du ruisseau. Ceci suggère aussi que les phases porteuses d’As sont de moins en moins stables au cours de la pédogénèse. En plus de la mobilisation physicochimique, cette étude a montré l’influence de l’activité bactérienne sur la spéciation de l’As dans les eaux du bassin versant, avec un relargage d’As(III) dissous avant celui du Fe(II) dans les eaux souterraines
In order to understand the pollution of waters in arsenic (As), it is important to know the biogeochemical processes involved in the transfer of this metalloid from the solid reservoir to waters. The aims were to evaluate (i) the contribution of As-rich solid phases weathering, from natural geochemical anomaly, through mineralogical characterization and (ii) the abiotic and biotic mobilization of As during hydrological monitoring and laboratory experiments. The soil profile showed a decrease of As bulk content during pedogenesis. Mineralogical characterization of the As-bearing phases showed an evolution in the soil profile from arsenates (Ba-rich pharmacosiderite) in the bedrock and the 135-165 cm soil horizon into Fe-oxyhydroxides (goethite, hematite and ferrihydrite) less and less rich in As towards the soil surface. The monitoring of dissolved As in the aqueous compartment showed the contribution of ground-, wetland and mine waters, runoff and soil solutions (in the surface horizons) to surface water pollution. Indeed, in situ monitoring of dissolved As in soil solutions showed a higher As release in the 0-5 cm soil horizon (25-119 μg. L-1) than in the deep soil horizons (6-56 μg. L-1), suggesting that As-bearing phases were less and less stable during pedogenesis. In addition to the physico-chemical mobilization, this study showed the influence of bacterial activity on As speciation in the waters of watershed, with the dissolved As(III) release before the Fe(II) in the groundwaters

A partir d'une centaine de questionnaire de musiciens de bal en limousin, l'etude permet d'analyser la morphologie de cette population (caracteristiques sociologiques et musicales) ainsi que les mecanismes de fonctionnement et de regulation des structures ou elle evolue (les orchestres). La specificite des acteurs apparait (issus de milieux modestes, ayant souvent un metier principal sans rapport avec la musique), de meme que la coexistence de deux types d'orchestres (typologies revelees par les analyses factorielles des correspondances). Mis a part les chefs d'orchestres (accordeonistes, fondateurs du groupe), le bal represente souvent pour les professionnels un moyen d'obtenir une couverture sociale et des ressources alimentaires regulieres leur permettant de pratiquer un autre genre de musique plus valorisant. Pour les amateurs, l'activite musicale participe d'une sociabilite forte qui s'accompagne de revenus substantiels. L'analyse historique de cette activite montre que si elle fut une veritable profession, elle en a perdu tous les attributs
A survey on a humdred of dance musicians in the french limousin area enlightens the sociological and musical backgrounds of this population of musicians as well as the mechanisms - of regulation of orchestra. Two main features are established among these performers; a modest origin with a profession generally types related to music and the coexistence of two types of orchestra (typologies showed by correspondences factorial analysis). Apart from the band master (usually accordeonist, group promoter) the ball is for the professional a mean to benefit from the social security system and to acquire a regular means of living; allowing them to pratice a more valuable kind of music. The musical activity enhances the strong sociability of the amateurs as well as a substantial extra-income. Along the history, the profession has seriously declined and lost its aura

Le travail presente une analyse chorologique de la flore vasculaire du limousin, region siliceuse de moyenne altitude du massif-central, qui s'inscrit dans le domaine floral atlantique. Il est fonde sur une interpretation de 1684 releves floristiques. Le premier chapitre precise les donnees generales sur le milieu de la dition (territoire etudie). Dans le deuxieme chapitre sont exposees les caracteristiques chorologiques globales de la dition ainsi que les grandes lignes de la vegetation de celle-ci. Une analyse statistique des observations est realisee. Le chapitre trois realise la synthese chorologique. Un zonage chorologique de la dition est recherche. Sur la base de 33 territoires phytogeographiques elementaires, differentes comparaisons sont effectuees: sequences des spectres chorologiques, analyse des poids des especes significatives, comparaison d'indices chorologiques, comparaison de cartes de repartition. Une organisation chorologique de la dition est proposee. Celle-ci appartient au domaine floral atlantique mais a la rencontre de trois secteurs: secteur du massif central, secteur aquitain et secteur ligerien, lesquels sont ici a leur limite. Des sous-unites de ces secteurs sont egalement proposees, districts et sous-districts et leurs caracteristiques chorologiques et ecologiques precisees

In this study, leaf anatomies of five species of Limonium Mill. (L. echioides, L. globuliferum, L. tamaricoides, L. anatolicum and L. Sinuatum) are studied. Taca belonging to five different sections of the genus Limonium as
L. echioides of the section Schizyhymenium, L. globuliferum of the section Sphaerostachys, L. tamaricoides of the section Limonium, L. anatolicum of the section Sarcophyllum and L. sinuatum of the section Pteroclados are used in this study. Throughout the species studied, L. tamaricoides and L. anatolicum are endemic to Turkey. In order to examine anatomy of leaves, the paraffin sectioning and hand cross sectioning methods are used. Avarage stomata length, width and number per 210.68µ
m x 263.27µ
m area of the leaves are examined and the stomata types due to epidermal cells are defined. Additionally, the vascular bundles, upper and lower epiderms of leaves of each species are defined. It is determined that except the species L. globuliferum and L. tamaricoides, the stomata density per 210.68µ
m x 263.27µ
m area of the leaves are approximately same for upper and lower epidermis, but in these species, the stomata numbers at upper epidermis is higher than the stomata numbers in lower epidermis, which might be related with the altitude, microclimate and habitat of these two species. It is also found that except the shoot leaf of L. sinuatum, the phloem is closer to lower epiderm than xylem in vascular bundles. But in shoot leaf of L. sinuatum, the phloem circularly covers the xylem and makes a closed circle around.

Master of Science
Department of Animal Sciences and Industry
Evan C. Titgemeyer
Seven ruminally cannulated heifers approximately 225 kg initial BW were used in a 7 × 4 Youden square design to determine the effects of different levels of limonene on ruminal Fusobacterium necrophorum populations. Treatments included: 1) control, 2) limonene at10 mg/kg diet DM, 3) limonene at 20 mg/kg diet DM, 4) limonene at 40 mg/kg diet DM, 5) limonene at 80 mg/kg diet DM, 6) CRINA-L (a blend of essential oil components) at 180 mg/kg diet DM, 7) tylosin at 12 mg/kg diet DM. Each period included 11 d with 10 d washouts between periods. Samples were collected on d 0 (before treatment initiation), 4, 7, and 10 for measuring F. necrophorum by most probable number (MPN) method using selective culture medium. Results indicate that CRINA-L (P = 0.52) and tylosin (P = 0.19) did not affect ruminal F. necrophorum populations. Limonene linearly decreased (P = 0.03) F. necrophorum populations, and the optimal dietary concentration for limonene was 40 mg/kg DM. Limonene did not affect ruminal degradation rate of lysine, NH3 concentration, or VFA profiles in ruminal fluid. Limonene was useful for reducing ruminal concentrations of F. necrophorum. It may have potential to control liver abscesses, although further research will be needed to assess the effect of limonene under feedlot conditions.

L'intérêt pour le développement de ressources bio-renouvelables pour la production de polymères a excessivement augmenté récemment. Le limonène époxydé est une source très prometteuse de bio-monomères. Son abondance et le faible coût de sa matière première les rendent appropriés comme alternatives à leurs homologues pétroliers conventionnels. L'oxyde de 1,2 limonène et le dioxyde de limonène, les dérivés de l'époxydation du limonène, sont en effet utilisés pour la synthèse de matériaux durables tels que les polycarbonates de limonène verts et les polyuréthanes sans isocyanates. Par conséquent, l'étude des moyens efficaces et économiques d'époxydation du limonène est d'un grand intérêt. L'activation de l'oxygène moléculaire en tant qu'oxydant dans l'époxydation sélective d'alcènes est une cible tentante en raison de son faible coût et de la nature écologique de cet oxydant. Cependant, l'oxygène moléculaire est inactif et il n'est activé qu'en présence de catalyseurs à base de métaux de transition réactifs et hautement sélectifs. Dans ce travail de recherche, une technique de post-greffage a d'abord été utilisée pour la substitution du cobalt dans la SBA-16 mésoporeuse comme support en utilisant directement l'acétylacétonate de cobalt comme précurseur. La silice mésoporeuse ordonnée, spécifiquement SBA-16 avec une surface spécifique élevée, un grand volume de pores et des tailles de pores uniformes s'est avérée efficace pour fournir des sites actifs haute mentdispersés pour l'époxydation de molécules d'alcène volumineuses comme le limonène. En utilisant cette méthode, une charge élevée de cobalt finement dispersé sur de la silice SBA16 a été obtenue. Les catalyseurs Co / SBA-16 (Co / Si = 4.5%) ont présenté une conversion et une sélectivité élevées dans l'époxydation aérobie Mukaiyama du limonène avec de l'oxygène moléculaire, l’oxydant le plus souhaitable, et de l'isobutyraldéhyde comme coréducteur dans des conditions très douces en présence du solvant vert l’acétate d'éthyle. Pour optimiser le rendement de la formation d'époxyde, un plan expérimental statistique a été appliqué pour une étude systématique des conditions de réaction par Central Composite Design (CCD) et le modèle Response Surface Methodology (RSM). 99% de conversion de limonène, 50% d'oxyde de 1,2 limonène et 32% de dioxyde de limonène ont été obtenus en200 minutes de temps de réaction dans les conditions de réaction optimisées : concentration d'isobutyraldéhyde de 1 mmol / ml (rapport IBA / limonène = 3.3) et 14.3 mg / ml de ivcatalyseur à 28 °C et 10 ml/min de débit d'O2. Pour améliorer davantage l'activité du catalyseur, l'incorporation de Co2+ à faible coordination dans la structure de la silice mésoporeuse SBA-16 a été réalisée par une méthode facile et verte « d’ajustement du pH »et le résultat a été comparé par rapport à notre méthode de post-greffage précédente. Ce catalyseur avec Co/Si = 1.1%, a montré une réactivité bien plus élevée pour l'époxydation aérobie du limonène avec des rendements d'époxyde plus élevés (~ 100%) (1,2 et 8,9-oxydede limonène et dioxyde de limonène) sous une pression d'oxygène de 44 psi. Une analyse cinétique approfondie de l'époxydation aérobie du limonène a été effectuée pour permettre de proposer un schéma réactionnel. Un nouveau mécanisme, dans lequel une réaction de surface entre un intermédiaire Co3+ OOperoxo et le limonène s'est avérée impliquée dans la formation du limonène époxydé. Malgré l'excellent résultat obtenu dans la première partie de cette étude pour l'époxydation aérobie du limonène en présence d'un aldéhyde comme coréducteur et de l'acétate d'éthylecomme solvant, la mise au point d'un procédé catalytique sans solvant ni réducteur est vraiment intéressante en termes de chimie verte. L'activité et la sélectivité des catalyseurs au ruthénium supportés sur divers charbons actifs ont été étudiées dans l'époxydation aérobie du limonène dans des conditions de réaction sans solvant / réducteur et sans initiateur. Le catalyseur préparé par échange de cations en utilisant le charbo activé Darco G60, avec la plus grande surface de mésopore et le plus grand volume de pores et la plus petite taille de particule de Ru (1.8 nm), s'est avéré donner la meilleure combinaison de conversion de limonène de 35% et de sélectivité d'époxyde de 57% (1,2 et 8,9-oxyde de limonène et dioxydede limonène) à 80 °C et 3 bars de pression d'oxygène.
The incentive for the development of bio-renewable resources for production of polymers has been excessively raised recently. Limonene epoxides are very promising sources of biomonomers which their abundance and low cost of raw material make them suitable as alternatives to their conventional petroleum derived counterparts. 1,2 limonene oxide and limonene dioxide, the products of limonene epoxidation, are utilized for synthesis of sustainable materials such as green limonene polycarbonates and non-isocyanate polyurethanes. Therefore, investigation of effective and economic ways of epoxidation of limonene is of high interest. Activation of molecular oxygen as an oxidant in selective epoxidation of alkenes is a tempting target owing to its low cost and environmentally friendly nature. However, molecular oxygen is inactive, and it is activated only in the presence of potent and highly selective transition metal catalysts.In this research work, first a post grafting technique was used for substitution of cobalt inmesoporous SBA-16 as a support, using directly cobalt acetylacetonate as the precursor. Ordered mesoporous silica specifically SBA-16 with high surface area, large pore volume and uniform pore sizes were found effective to provide highly dispersed active sites for the epoxidation of bulky alkene molecules like limonene. Using this method, a high loading of cobalt finely dispersed on SBA-16 silica was obtained. The Co/SBA-16 (Co/Si= 4.5%) catalysts exhibited high conversion and selectivity in aerobic Mukaiyama epoxidation of limonene with molecular oxygen as the most desirable oxidant and isobutyraldehyde as a coreductant under very mild conditions in the presence of the green solvent ethylacetate. Tooptimize the yield of epoxide formation, a statistical experimental design was applied for systematic investigation of reaction conditions by Central Composite Design (CCD) and Response Surface Methodology (RSM) model. 99% limonene conversion, 50% 1,2 limoneneoxide and 32 % limonene dioxide were obtained with in 200 minutes of reaction time under the optimized reaction conditions: 1 mmol/ml isobutyraldehyde concentration(IBA/limonene ratio=3.3) and 14.3 mg/ml catalyst amount at 28°C and 10 ml/min O2 flowrate. To further enhance the activity of catalyst, incorporation of low coordination Co2+within the structure of mesoporous silica SBA-16 has been accomplished through a facile and green “pH adjusting” method and the result compared with those of our previous postgrafting method. This catalyst with Co/Si=1.1%, showed quite higher reactivity for the aerobic epoxidation of limonene with higher epoxide yields (∼100%) (1,2 and 8,9- limoneneoxide and limonene dioxide) under 44 psi oxygen pressure. A thorough kinetic analysis of aerobic epoxidation of limonene was performed to allow proposing a reaction scheme. A new mechanism, in which a surface reaction between a Co3+OO−peroxo intermediate and limonene was found to be involved in the formation of the epoxidized limonene. Despite the excellent result obtained in the first part of this study for aerobic epoxidation of limonene in the presence of an aldehyde as a coreductant and ethylacetate as a solvent,developing a solvent- and reductant-free catalytic process is really appealing in terms of green chemistry. The activity and selectivity of ruthenium catalysts supported on various activated carbons have been investigated in aerobic epoxidation of limonene undersolvent/reductant and initiator free reaction conditions. The catalyst prepared by cation exchange using activated carbon Darco G60, with the highest mesopore surface area and pore volume and the lowest Ru particle size (1.8 nm), was found to give the best combination of limonene conversion of 35% and epoxide selectivity of 57% (1,2 and 8,9- limonene oxideand limonene dioxide) at 80 °C and 3 bar oxygen pressure.

Sous irradiation laser, la double liaison endocyclique du limonène apparait plus réactive que l'exocyclique. Ceci est illustré par l'obtention du psilomène et par l'addition de méthanol et d'acrylonitrile. La double liaison située en -1,2 est également concernée dans la sulfuration laser du limonène à partir du soufre moléculaire qui permet la formation d'epithio-1,2 p-menthènes, composés non accessibles thermiquement. Sur le plan de la synthèse, cette méthode d'obtention de thiiranes semble particulièrement prometteuse

On distingue des corps composes uniquement de perodotites mantelliques et des corps mixtes. Les massifs mixtes, les plus nombreux en limousin, contiennent tous des roches cumulatives. La coexistence a l'affleurement de tectonites et de roches cumulatives permet d'assimiler les massifs "stratifies" a des elements constitutifs d'un complexe ophiolitique. Les massifs purement matelliques sont representes par trois exemplaires; l'etude des massifs de la rebiere et du larzac montre qu'ils sont constitues de lherzolites a spinelle d'origine sous continentale, contenant des niveaux websteritiques. Ces deux types de massifs n'ont pas subi la meme evolution metamorphique. Leur mise en place est egalement differente

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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES
Biodiversity, one of the fundamental properties of nature, is a source of immense economic potential. Brazil holds a rich biodiversity, and is considered one of the most important mega-diverse countries on the planet. Among the various links that make up this biodiversity Brazilian native flora noteworthy. Despite this, there have been few studies that promote intelligent and rational use of this genetic resource. Domestication and breeding of native plants, including those already known and used by local or regional populations, but without penetration at the national or international market is the great opportunity offered to the countries rich in genetic resources. Medicinal and aromatic plants represent a significant part of this potential market, and the lemongrass-Brazilian species (Lippia alba) is an important example of medicinal and aromatic plant, long used in folk medicine for his duties as soothing, antispasmodic, sedative, and produce various kinds of essential oils can be used by the perfume industry, food and cleaning products, beyond the control of pests and diseases in agriculture. Thus, the objective of this study was to evaluate the genetic variability, genetic parameters and the agronomic behavior of different accesses of L. alba, coming from the metropolitan region of the State of Rio de Janeiro. The experiment was conducted in November 2011 on Medicinal Plants Sector of Agronomy Institute of Rural Federal University of Rio de Janeiro, and crops were obtained in the spring of 2013 and summer of 2014. This study was divided into three chapters: Polymorphism in clones of L. alba coming from the metropolitan area of Rio de Janeiro (Chapter I); Genetic variation for morphological characters in clones of A. alba (Chapter II) and seasonality effect in producing chemotypes of L. alba (Chapter III). In Chapter I the accessions were grouped into dendrogram, five groups being formed and the group I met two similar access (UFRRJLA 17 and UFRRJLA 18). In Chapter II it was shown that the characters analyzed showed variability according to the season (spring or summer) confirming the strong influence of the environment on quantitative variables. The total dry matter and yield were higher in access UFRRJLA05 with citral chemotype, which showed the highest average values in the two seasons in which the data were evaluated. As for the essential oil yield and productivity stood out access UFRRJLA03 with limonene-carvone chemotype, both in spring and in summer.
A biodiversidade, uma das propriedades fundamentais da natureza, ? fonte de imenso potencial de uso econ?mico. O Brasil ? detentor de uma rica biodiversidade, e ? considerado um dos pa?ses megadiversos mais importantes do planeta. Dentre os v?rios elos que comp?e esta biodiversidade a flora nativa brasileira merece destaque. Apesar disto, poucos t?m sido os estudos que promovem a utiliza??o inteligente e racional destes recursos gen?ticos. A domestica??o e o melhoramento de plantas nativas, incluindo aquelas j? conhecidas e utilizadas por popula??es locais ou regionais, por?m sem penetra??o no mercado nacional ou internacional, ? a grande oportunidade que se oferece aos pa?ses ricos em recursos gen?ticos. As plantas medicinais e arom?ticas representam uma parte expressiva deste mercado em potencial, sendo que a esp?cie erva-cidreira-brasileira (Lippia alba) ? um exemplo importante de planta medicinal e arom?tica, h? muito tempo utilizada pela medicina popular por suas fun??es como calmante, antiespasm?dica, sedativo, al?m de produzir v?rios tipos de ?leos essenciais podendo ser utilizada pela ind?stria de perfumes, alimentos e produtos de limpeza, al?m do controle de pragas e doen?as na agricultura. Diante do exposto, o objetivo deste trabalho foi avaliar a variabilidade gen?tica e par?metros gen?ticos de acessos de L. alba e o comportamento agron?mico de diferentes clones oriundos da regi?o Metropolitana do Estado do Rio de Janeiro. O experimento foi instalado em novembro de 2011 no Setor de Plantas Medicinais do Instituto de Agronomia da Universidade Federal Rural do Rio de Janeiro, e as colheitas foram obtidas na primavera de 2013 e no ver?o de 2014. Este estudo foi dividido em tr?s cap?tulos: Polimorfismo em clones de L. alba oriundos da regi?o Metropolitana do Rio de Janeiro (Cap?tulo I) e Par?metros gen?ticos e avalia??o agron?mica em clones de L. alba (Mill) N.E.Brown em duas esta??es no ano (Cap?tulo II). No cap?tulo I os acessos foram agrupados em dendrograma, sendo formados cinco grupos e o grupo I reuniu os dois acessos similares (UFRRJLA 17 e UFRRJLA 18). No cap?tulo II foi demonstrado que os caracteres analisadas apresentaram comportamento vari?vel conforme a esta??o do ano (primavera ou ver?o) confirmando a forte influ?ncia do ambiente sobre as vari?veis quantitativas. A mat?ria seca total e a produtividade foram maiores no clone com quimiotipo citral (UFRRJLA05), com os maiores valores m?dios nas duas esta??es do ano em que os dados foram avaliados. J? para o rendimento e produtividade de ?leo essencial destacou-se o acesso com quimiotipo limoneno-carvona (UFRRJLA03), tanto na primavera quanto no ver?o

La géographie de l'information géographique c'est l'étude de la répartition spatiale des différents systèmes de production et de consommation de l'information géographique. (Chrisman, in Roche 2000). Dans ce contexte scientifique, l'étude des inégalités géographiques dans le recours aux Technologies de l'Information Géographique (TIG) est certainement l'axe de recherche le plus pratiqué(qualification et niveau d'équipement des collectivités, typologies des informations géographiques produites, transversalitédes représentations spatiales des techniciens vers les décisionnaires, etc. ). Pour ce doctorat consacréaux outils et méthodes de l'ingénierie des TIG, le Limousin a constituéun terrain d'étude aux atouts géomatiques plus qualitatifs que quantitatifs. La réflexion présentée a étéconduite àposteriori d'actions-recherche réalisées (entre 2000 et 2010) dans des groupes de travail pluri-thématiques et pluri-professionnels désireux de réaliser et de partager des diagnostics territoriaux. La première partie est consacrée aux usages des SIG dans les collectivités territoriales (une communautéd'agglomération, un Pays et un Conseil régional), tandis que la seconde investie innove en proposant des méthodes géo-épidémiologiques en fédérant des acteurs de santépublique. D'abord rétrospectif puis prospectif, ce travail présentésous la forme d'une thèse universitaire en géographie traite donc de l'ingénierie géomatique comme d'un média entre l'espace géographique, sa gestion et les prises de décisions qui le concernent : il s'adresse donc àl'ensemble des acteurs attentifs aux inégalités géographiques afférentes àleurs compétences et/ou leurs préoccupations territoriales
The geography of the geographical information it is the survey of the spatial distribution of the different systems of production and consumption of the geographical information. (Chrisman, in Roche 2000). In this scientific context, the survey of the geographical inequalities in the recourse to the Technologies of the Geographical Information (TIG) is certainly the axis of research the more practiced (qualification and level of equipment of the collectivities, typologies of the geographical information produced, transverse approach of the spatial representations of the technicians toward the decision-makers). For this doctorate dedicated to the tools and methods of the engineering of the TIG, Limousin constituted a regional land of survey to the assets geomatics more qualitative than quantitative. This reflection has been driven a posteriori of action-research achieved (between 2000 and 2010) in multi-thematic and multi-professional groups of work anxious to achieve and to share territorial diagnoses. The first part is dedicated to the uses of the SIG in the territorial collectivities, while the enclosed second innovates while proposing geo-epidemiological methods while federating actors of public health. First retrospective then prospective, this work presented under the shape of an academic thesis in geography is therefore about the geomatic engineering like a media between the geographical space, its management and the holds of decisions that concern it: it goes therefore to the set of the actors attentive to the pertaining geographical inequalities to their expertises and/or their territorial preoccupations

Récemment, l’apparition de la notion de « tête de bassin » montre la volonté de territorialisation de la gestion de l’eau et la prise en compte des régions aux réseaux hydrographiques denses. Dans la bibliographie, ces territoires sont composés des bassins versants de rang 0 et 1, marqués par des restructurations sociales et des « fronts écologiques ». La diversité des petits cours d’eau et zones humides qui s’y trouvent entraîne des définitions scientifiques et surtout écologiques difficilement transposables. Pourtant, les gestionnaires et pouvoirs publics s’efforcent d’en donner une définition cartographique dont dépend la planification d’actions en leur faveur. En effet, les restructurations territoriales ne sont pas sans impacts. La production sédimentaire « naturelle » de la tête de bassin est amplifiée par les activités humaines. Des enjeux forts pour les populations de ces régions sont identifiés, ils seront réellement perçus lorsque l’étendue des têtes de bassins sera connue. Nos principaux résultats de recherche ont été d'effectuer les premiers pas vers la cartographie des petits cours d'eau et des surfaces de têtes de bassin par grand type hydro-géomorphologique à l'échelle mondiale. Nous avons proposé des cartographies des têtes de bassin françaises. Ces cartes constituent un préalable à l'analyse de leur qualité environnementale, ichtyologique, et de la qualité de leurs eaux, en particulier du bassin de la Loire. Nous avons caractérisé les ruisseaux limousins, et plus particulièrement ceux du Pays Monts et Barrages dans le bassin amont de la Vienne d’un point de vue hydromorphologique et hydroécologique en lien avec les activités humaines
Recently, the appearance of « headwater basin » notion shows the willing of territorial water management, and notably taking care of region that have dense hydrographic network. In bibliography, those territories are composed of 0 and 1 range basins, marked by social restructurings and "éco-frontier". The diversity of the small streams and wetlands generate scientific and ecologic definitions hardly transposable. However, the administrators and public authorities try to give a cartographic definition which depends actions of preservation and restoration. Territorial restructurings are not without impacts. The “natural” sedimentary production in the headwater basin is increased by the human activities. Strong stakes for the populations of these regions are identified; they will be perceptible only when we will know the sprawling of the headwater basin territories. Our main research results did the first steps towards the mapping of small streams linear and headwater surfaces by hydro-geomorphologic types for world. We offered mappings of the french headwater. Those maps were a prior to an analysis of their environmental quality, particularly for Loire basin. We have characterized streams of Limousin, particularly streams of the “Pays Monts et Barrages” according to hydromorphological and hydroecological particularity linked to human activities

En Limousin, de 1660 à 1789, l'inscription de la Réforme catholique dans les territoires et les pratiques collectives de dévotion des fidèles se déroule en douceur. Pourtant la formation exigeante des prêtres dans les séminaires sulpiciens de Limoges et de Tulle, à compter respectivement de 1660 et 1697, aurait pu construire les conditions d'une cléricalisation accélérée et d'un possible divorce avec la population. Il n'en est rien. Au contraire, tout en revendiquant l'exceptionnalité du sacerdoce et en maintenant une distance avec les fidèles, le clergé limousin a su transmettre une foi renouvelée à une population majoritairement analphabète, sans précipiter la moindre rupture religieuse. Ainsi, la parole ecclésiastique portée en chaire dessine un possible salut accessible à chacun, privilégiant une pastorale de l'espérance. De même, les interventions conduites sur le territoire paroissial ne modifient que marginalement l'espace sacré et, le plus souvent, avec l'accord des paroissiens. Cela vaut également dans la mise en oeuvre collective des dévotions, lors des processions ou dans la vie des confréries. L'Eglise favorise une affirmation religieuse communautaire sous direction curiale, sans désavouer les usages cultuels anciens, sauf s'ils présentent des atteintes jugées manifestes au sacré. Elle les réinstalle simplement dans une chaîne d'intercession hiérarchique auprès de Dieu. En Limousin, de la seconde moité du XVIIe siècle à la Révolution, l'Eglise a donc choisi d'insérer sa démarche pastorale dans les cadres proposés par une société fortement marquée par des références ou des engagements collectifs
In the Limousin, from 1660 to 1789, catholic Reform took off gently, in the devotional habits of the faithful. The demanding training, in the tradition of Saint Sulpice, of priests in the seminaries of Limoges (from 1660) and Tulle (from 1697) could easily have led to the rapid domination of the Church and a possible split with the population. This did not, however, happen. On the contrary, while puttting forward claims for the exceptional nature fo priesthood and maintaining a distance from the faithful, the Limousin clergy managed to pass on a renewed faith to a largely illiterate population, without causing the slightest religious breach. So it was that hope preached from the pulpit, in terms of possible salvation for all. In the same way, parish ground was only modified slightly, and mostly with the agreement of parishioners. The same was true of devotional practices during processions and in the life of brotherhoods. The Church favoured a community expression of belief, under the leadership of the clergy, without rejecting traditional practices, unless these were perceived as directyl harmful. The practices were simply given their proper place in the hierarchy of intercession to God. In the Limousin, from the second half of the 17th century until the Revolution, the church, then, made the choice of fitting its pastoral scheme into the framework of a society strongly influenced by collective references or commitments

Les cistreciens du diocèse de Limoges s'implantent dans des salti délaissés. Les premiers investissements des communuatés sont dès lors dévolus à l'assainissement des terres, l'agriculture et l'hydraulique, tandis que les abbayes se révèlent bien souvent bâties à l'économie. L'austérité est de mise, en cohérence avec ces nombreux mouvements à vocation érémitique nés de la réforme grégorienne. Il faut attendre le XIIIè siècle pour assister à une réapparition de la figure bidimentionnelle. Les monastères évoluent alors d'un système en faire-valoir direct à une économie de fermage, se rapprochant d'un modèle clunisien rejeté au préalable. Les revenus engrangés permettent peut-être d'investir dans des créations artistiques plus luxueuses. Les inhumations laïques conduisent aussi à des changements dans le décor des abbatiales et introduisent une iconographie propre. Ce tournant du XIIIème siècle est également marqué par des poussées capétiennes tangibles en Aquitaine. Si l'art de bâtir relève plus d'un goût Plantagenêt encore largement tributaire des formes romanes, les décors ajoutés au XIIIè siècle témoignent de liens étroits avec un art du nord. Les cisterciens sont aussi les révélateurs du glissement vers un premier art gothique. Néanmoins, un certain nombre de formules propres au gothique capétien sont rejetées. Entre austérité et acceptations progressives de l'image, entre roman et gothique, entre Plantagenêts et Capétiens, entre saltus et ager, les moines cisterciens du diocèse de Limoges s'inscrivent comme un maillon indispensable à la compréhension des créations artistiques aquitaines des XIIème et XIIIème siècles
The Cistercians of the diocese of Limoges are established in forsaken salti. The fisrt investments of the collunities deal consequently with the cleansing of the grounds agriculture and hydraulics, while their abbeys appear very often built with economy. The austerity is of setting, in coherence with these many movements with eremetic vocation born from the Gregorian reform. It is necessary to await XIIIe century to attend a reappearance ofthe tow-dimensional figure. The monasteries move then of a system in farming by the owner with a saving in tenant farming, approaching a clunisian model rejected as a preliminary. Perhaps the garnered incomes make it possible to invest in more luxurious artistic creations. The laic burials also lead to changes inthe decoration of abbey and introduce of an own iconography. This turning of XIIIe century is also marked by tangible capetians pusches in Aquitaine. If art to build changing more than one Plantegenêt taste still largely dependend on Romance forms, the decorations added to XIIIe century testify to close links with an art of North. The Cistercians are also revealing slip towards a first Gothic art. Nevertheless, a certain number of formulas suitable for the capetian Gothic are rejected. Between austerity and progressive acceptances of the image, between novel and Gothic, Plantagenêts and Capetians, saltus and ager, the cistercians monks of the diocese of Limoges are registered like an essential link to the comprehension of Aquitanian artistic creations of XIIe and XIIIe centuries

d-Limonene (Lim) was used in various polymer formulations to achieve a more sustainable polymerization. Lim is a renewable and essentially non-toxic compound, derived from citrus fruit peels, that may replace some of the many toxic and fossil-based chemicals used in polymer synthesis. Bulk free-radical polymerizations of n-butyl acrylate (BA) with Lim were performed to investigate Lim co-polymerization kinetics and estimate the monomer reactivity ratios, important parameters in the prediction of copolymer composition. Kinetic modeling of the BA/Lim copolymerization was performed with PREDICI simulation software. The model supports the presence of a significant degradative chain transfer reaction due to Lim. This reaction mechanism is due to the presence of allylic hydrogen in Lim. Nonetheless, relatively high molecular weight polymers were produced. It was concluded that Lim behaves more like a chain transfer agent than a co-monomer. Terpolymerizations of BA, butyl methacrylate (BMA) with Lim were then performed. In order to predict the terpolymer composition, the monomer reactivity ratios for BA/BMA were estimated. By applying the three pairs of co-monomer reactivity ratios to the integrated Mayo-Lewis equation, terpolymer compositions were ably predicted up to high monomer conversion levels. Lim was then used as a chain transfer agent to prepare core-shell latex-based pressure sensitive adhesives (PSA) comprising BA and styrene via seeded semi-batch emulsion polymerization. By varying the concentration of Lim and divinylbenzene crosslinker, the core polymer microstructure was modified to yield different molecular weights and degrees of crosslinking. The core latex was then used as a seed to prepare core-shell latexes. By changing the Lim concentration during the shell-stage polymerization, the molecular weight of shell polymer was also modified. The latexes were characterized for their microstructure and were cast as films for PSA performance evaluation. The PSA performance was shown to be highly related to the polymer microstructure. Tack and peel strength showed a decrease with increasing Lim concentration. Shear strength went through a maximum with a core Lim concentration increase from 0 to 5 phm.

Tese (doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia Química
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No presente trabalho são determinados os valores das constantes da taxa de propagação através da técnica de polimerização por pulso de laser (PLP) para dois sistemas, estireno puro e estireno na presença de diferentes frações molares de d-limoneno, conforme a metodologia recomendada pela IUPAC. Os valores obtidos mostraram que a constante da taxa de propagação para o experimento de polimerização do estireno na presença de d-limoneno tem o mesmo valor da constante da taxa de propagação do estireno puro, ambos em concordância com valor publicado pela IUPAC para a polimerização do estireno puro. Os dados obtidos das reações de polimerização em massa do estireno na presença do d-limoneno foram utilizados em conjunto com a equação de Mayo para obter o valor da constante de transferência de cadeia para a molécula de d-limoneno, apresentando um valor bem superior ao da transferência de cadeia para a molécula de estireno, conforme valores retirados da literatura. Também são realizadas algumas polimerizações em massa do d-limoneno puro via radicais-livres, onde a conversão não ultrapassou um valor de 3%, porém comprova a possibilidade desta polimerização. The aim of this work is to evaluate the chain transfer rate constant and propagation rate constant for the styrene polymerization in the d-limonene presence. The chain transfer constant to d-limonene (Ccta) was evaluated by Mayo procedure using both the number-average molecular weight (Mn) and the weight-average molecular weight (Mw), where Ccta = kcta/kp. Results allowed us to conclude that different initiator concentrations and temperatures have no influence on the Ccta value. Pulsed-laser-polymerization was carried out for the styrene pure and styrene/d-limonene system in a temperature range of zero to 30°C. Propagation constant rate values were evaluated as well as the Arrhenius number (A) and the Activation Energy (Ea) and compared to the IUPAC work values. Results showed that the d-limonene molar fraction had no influence on the propagation rate constant for the styrene polymerization.

L'objectif de cette thèse est d'identifier, à l'aide d'un modèle de gravité, les variables qui ont une influence sur les échanges interrégionaux et internationaux de la Région LIMOUSIN sur la période 1990-2001. La démarche s'organise en quatre étapes. La première étape est une revue théorique des fondements du modèle de gravité. La deuxième étape propose une revue empirique des applications du modèle pour les échanges internationaux et des améliorations de sa spécification. La troisième étape consiste à analyser d'une manière très détaillée, l'orientation géographique des échanges interrégionaux et internationaux de marchandises de la Région LIMOUSIN selon les différents niveaux de désagrégation de la Nomenclature Statistiques des Transports et selon les modes de transport. La quatrième étape propose, au vu des enseignements des trois étapes précédentes, une adaptation économétrique du modèle de gravité aux différents niveaux de désagrégation pour montrer si la distance, la " masse " économique, la distance économique, la contiguïté ou encore le niveau des infrastructures routières et ferroviaires sont des facteurs pertinents pour l'explication des échanges d'une Région. Malgré les difficultés de transposer à un niveau régional un outil utilisé essentiellement à un niveau international et les limites liées à la disponibilité des données au niveau d'une Région, nos résultats restent conformes à ceux de la littérature empirique
The aim of this thesis is to identify the variables which influence the interregional and international trade of LIMOUSIN Region using a gravity model from 1990-2001. Our research is organized in four steps. The first one is a theoretical survey of the foundations of gravity model. The second one relates an empirical survey of empirical studies concerning the gravity model for international trade. Improvements of this specification have been proposed in the light of this survey. The third step consists in the analysis of the geographical orientation of interregional and international goods trade of LIMOUSIN Region according to different disaggregated levels and means of transport. The last step of this thesis proposes, considering the previous step, an econometric adaptation of gravity model to different disaggregated levels to show that geographical distance, economic “mass”, economic distance, adjacency or infrastructure levels (road, railway) are relevant factors to explain the trade of a Region. Due to scarcity of data at a regional level, it is difficult to adapt the gravity model as a tool as it is mainly used in international trade. Nevertheless, our results remain in conformity with the empirical literature