Die Nutzung von Kraftstoffen auf der Basis von Biodiesel erlaubt es, konventionelle, etablierte Antriebstechniken mit Nachhaltigkeit zu kombinieren. Daher kann in den nächsten Jahren mit einer weiteren weltweiten Steigerung der Biodieselproduktion gerechnet werden. Damit verbunden ist jedoch auch ein Anstieg der anfallenden Menge an Glycerol, das bei der Herstellung von Biodiesel als Koppelprodukt entsteht. Da traditionelle Märkte für Glycerol kaum mehr Wachstum zeigen, müssen neue Wege zur effizienten Verwertung von Glycerol gefunden werden. Die vorliegende Arbeit beschäftigt sich mit der heterogen-katalysierten Umsetzung von Glycerol zu Acrolein. Unter Verwendung von ZSM-5-Katalysatorproben mit unterschiedlichem Si/Al-Verhältnis und phosphorsäure-modifizierten Katalysatorproben konnte die Existenz von Synergieeffekten zwischen den texturellen, strukturellen und aciden Eigenschaften in der heterogen-katalysierten Glyceroldehydratisierung zu Gunsten der Acroleinselektivität eindeutig nachgewiesen werden. Eine selektive Umsetzung von Glycerol zu Acrolein wird daher an solchen Katalysatorproben ermöglicht, die ausgewogene texturelle, strukturelle und acide Eigenschaften aufweisen.

The effects of corrosion inhibitors on water quality and the distribution system were studied. This dissertation investigates the effect of inhibitors on iron surface roughness, copper surface roughness, and copper release. Corrosion inhibitors included blended poly/ortho phosphate, sodium orthophosphate, zinc orthophosphate, and sodium silicate. These inhibitors were added to a blend of surface water, groundwater, and desalinated brackish water. Surface roughness of galvanized iron, unlined cast iron, lined cast iron, and polyvinyl chloride was measured using pipe coupons exposed for three months. Roughness of each pipe coupon was measured with an optical surface profiler before and after exposure to inhibitors. For most materials, inhibitor did not have a significant effect on surface roughness; instead, the most significant factor determining the final surface roughness was the initial surface roughness. Coupons with low initial surface roughness tended to have an increase in surface roughness during exposure, and vice versa, implying that surface roughness tended to regress towards an average or equilibrium value. For unlined cast iron, increased alkalinity and increased temperature tended to correspond with increases in surface roughness. Unlined cast iron coupons receiving phosphate inhibitors were more likely to have a significant change in surface roughness, suggesting that phosphate inhibitors affect stability of iron pipe scales. Similar roughness data collected with new copper coupons showed that elevated orthophosphate, alkalinity, and temperature were all factors associated with increased copper surface roughness. The greatest increases in surface roughness were observed with copper coupons receiving phosphate inhibitors. Smaller increases were observed with copper coupons receiving silicate inhibitor or no inhibitor. With phosphate inhibitors, elevated temperature and alkalinity were associated with larger increases in surface roughness and blue-green copper (II) scales.. Otherwise a compact, dull red copper (I) scale was observed. These data suggest that phosphate inhibitor addition corresponds with changes in surface morphology, and surface composition, including the oxidation state of copper solids. The effects of corrosion inhibitors on copper surface chemistry and cuprosolvency were investigated. Most copper scales had X-ray photoelectron spectroscopy binding energies consistent with a mixture of Cu2O, CuO, Cu(OH)2, and other copper (II) salts. Orthophosphate and silica were detected on copper surfaces exposed to each inhibitor. All phosphate and silicate inhibitors reduced copper release relative to the no inhibitor treatments, keeping total copper below the 1.3 mg/L MCLG for all water quality blends. All three kinds of phosphate inhibitors, when added at 1 mg/L as P, corresponded with a 60% reduction in copper release relative to the no inhibitor control. On average, this percent reduction was consistent across varying water quality conditions in all four phases. Similarly when silicate inhibitor was added at 6 mg/L as SiO2, this corresponded with a 25-40% reduction in copper release relative to the no inhibitor control. Hence, on average, for the given inhibitors and doses, phosphate inhibitors provided more predictable control of copper release across changing water quality conditions. A plot of cupric ion concentration versus orthophosphate concentration showed a decrease in copper release consistent with mechanistic control by either cupric phosphate solubility or a diffusion limiting phosphate film. Thermodynamic models were developed to identify feasible controlling solids. For the no inhibitor treatment, Cu(OH)2 provided the closest prediction of copper release. With phosphate inhibitors both Cu(OH)2 and Cu(PO4)·2H2O models provided plausible predictions. Similarly, with silicate inhibitor, the Cu(OH)2 and CuSiO3·H2O models provided plausible predictions.

Ce projet scientifique concerne le développement de nouvelles méthodes efficaces de fonctionnalisation d’imines par des procédés organocatalysés et photocatalysésDans un premier temps la réaction photocatalysée d’alkylation d’énamines en conditions douces à été étudiée. L’utilisation de photocatalyseurs sous forme de complexes organométalliques d’Iridium a permis de réaliser la double fonctionnalisation d’ènecarbamates, permettant ainsi d’obtenir des substituts d’imines hautement substitués. Ce procédé permet de s’affranchir de l’utilisation de métaux lourds et ne nécessite qu’une activation par la lumière visible pour fonctionner. Cette transformation radicalaire éco-compatible à par la suite été soumise à une étude mécanistique approfondie. Dans une deuxième partie, la réaction d’aza-Friedel-Crafts organocatalysée par des acides de Brønsted chiraux à été étudiée. Dans cette réaction, la bi-fonctionnalité des acides chiraux dérivés du BINOL a été exploitée. Elle permet l’addition énantiosélective d’une grande variété d’indoles substitués sur des acyl-pyrrolidinones générées in situ. Les composés synthétisés présentent des structures bioactives intéressantes notamment sur le système nerveux central.Enfin, la première réaction de Povarov asymétrique impliquant des amino-hétérocycles comme précurseurs de 2-azadiènes à été décrite. Cette étude s’appuie sur des travaux antérieurs du laboratoire et permet la synthèse des analogues hétérocycliques de tétrahydroquinoléines précédemment décrites. Le procédé met en jeu une séquence multicomposants réduction/Povarov catalysée par des acides phosphoriques chiraux et permet l’accès rapide à une large bibliothèque d’analogues. / The aim of this study is the development of new methodologies for imines functionalization by organocatalysed and photocatalysed processes.First, a photocatalysed alkylation reaction of enecarbamates have been described. The use of organometallic Iridium complexes allowed the double functionalization of enecarbamates leading to highly substituted imines surrogates. This process is a green alternative to the use of heavy metals and only needs visible light as an renewable energy source to proceed. This environment-friendly radical transformation has been submitted to mechanistic study.In a second part, an aza-Friedel-Crafts reaction organocatalysed by chiral Brønsted acid has been studied. The bi-fonctionnality of chiral phosphoric acids has been advantageously used to perform the Friedel-Crafts addition of various substituted indole to in situ generated acyl-iminium ions. The compounds obtained by this methodology are showing interesting biological activities on central nervous system. Finally, the first enantioselective Povarov reaction involving amino-heterocycles as 2-azadienes precursors has been reported. This reaction is based on previous lab reports and the synthesis of tetrahydroquinoline analogues has been described. The multicomponent reduction/Povarov reaction sequence catalyzed by chiral phosphoric acids derived gives a rapid access to a wide library of bioactives analogues.

Este estudo se propõe a analisar a resposta pulpar de dentes humanos a preparos cavitários de classe V, em função de duas diferentes técnicas de instrumentação e de duas diferentes técnicas de restauração. Para tal, cavidades classe V, nas superfícies vestibulares de 48 pré-molares hígidos de pacientes entre 11 e 25 anos, que estavam em tratamento ortodôntico, foram preparadas e restauradas de acordo com os seguintes grupos experimentais: G 1 (n=24) - preparos cavitários realizados com ponta diamantada em alta rotação, restaurados com guta-percha plastificada, cimento ionômero de vidro e verniz cavitário (G 1A; n=12) ou com técnicas adesivas (sistema restaurador adesivo aplicando-se o condicionamento ácido total) e cimento ionômero de vidro (G 1B; n=12); G 2 (n=24) - preparos cavitários com ponta CVD ativada por ultrassom, restaurados com gutapercha plastificada, cimento ionômero de vidro e verniz cavitário (G 2A; n=12) ou com técnicas adesivas (sistema restaurador adesivo aplicando-se o condicionamento ácido total) e cimento ionômero de vidro (G 2B; n=12); e G 3 (controle; n=4) - dentes que foram extraídos sem a realização de qualquer procedimento. Os preparos cavitários foram realizados mantendo o assoalho da cavidade o mais próximo possível da polpa, no entanto, sem provocar exposição pulpar. Os dentes foram extraídos após três períodos experimentais (imediato, sete e trinta dias após o preparo cavitário), fixados, descalcificados, e processados histologicamente. Cortes teciduais longitudinais seriados de 5 m foram obtidos, corados pelas técnicas de H & E e de Brown & Brenn, e examinados em microscopia ótica. As avaliações morfométricas e por escores foram realizadas e os resultados das mesmas, submetidos, respectivamente, aos testes estatísticos de Mann-Whitney e de Kruskal-Wallis/Dunn, adotando-se um nível de significância de 5%. No período inicial, todos os grupos experimentais (1A, 1B, 2A e 2B) exibiram ligeiro desarranjo da camada odontoblástica vacuolizada e leve invasão da zona acelular de Weil. Não houve diferença entre os grupos experimentais iniciais e o grupo controle. No intervalo de sete dias, pôde-se observar redução da camada odontoblástica, muitos núcleos de odontoblastos aspirados nos túbulos dentinários, alguns espécimes com ausência de pré-dentina e resposta inflamatória aguda com hemorragia. Trinta dias depois, cinco espécimes do total avaliado apresentaram dentina terciária; dois espécimes do grupo 1B apresentaram necrose relacionada com a presença de bactérias nos túbulos dentinários; e os demais mostraram graus variados de inflamação crônica, associados a restaurações adesivas ou a processos de reparo, com proliferação de vasos e persistência de focos de hemorragia. Portanto, os dois tipos de instrumentação cavitária promovem respostas pulpares similares entre si, mas as diferentes técnicas restauradoras promovem efeitos significativamente diferentes sobre o complexo dentinopulpar. / The aim of this study is to analyze the pulp response of human teeth to class V cavity preparation, in function of two different instrumentation and restorative techniques. Class V cavities were made on the buccal surfaces of 48 sound human pre-molars from orthodontic patients from 11 to 25 years, and were divided as follows: G1 (n=24) cavity preparations were made with diamond bur under high speed, restored with either plasticized gutta-percha, glass ionomer cement and surface coated with varnish (G1A) or adhesive protocol (total etch technique and adhesive system application) with glass ionomer filling (G1B); G2 (n=24) cavity preparations were made with diamond CVD point and ultrasonic device, restored with either plasticized gutta-percha, glass ionomer cement and surface coated with varnish (G2A) or adhesive protocol (total etch technique and adhesive system application) with glass ionomer filling (G2B); and control group G3 (n=4) extracted teeth with no previous cavity preparation. All avities were prepared with the cavity floor as close to the pulp as possible, without causing pulp exposure. Teeth extractions were made in three experimental periods (immediate, 7 and 30 days after cavity preparation) and right after extraction they were submitted to histological procedures. Longitudinal tissue serial sections of 5 mm were obtained, H&E and Brown&Brenn stained, and analyzed under optical microscope. Morphometric and score evaluations were carried out and data from both were, respectively, submitted to Mann-Whitney and Kruskal-Wallis/Dunn tests, with 5% significance. Immediately, all experimental groups (1A, 1B, 2A and 2B) exhibited a discrete disorganization of the odontoblastic layer and invasion of the Weil zone. There was no difference between experimental and control groups. At 7-day interval, a decrease of the odontoblastic layer was observed. Many odontoblasts nucleus were seen displaced into the dentinal tubules. Some specimens showed absence of pre-dentine and inflammatory pulp response with hemorrhage. Thirty days later, five specimens presented tertiary dentin formation; two specimens from group 1B presented necrosis coincident with bacteria inside the dentinal tubules; the other specimens showed various degrees of chronic inflammation, associated to adhesive restorations or repair processes, with blood vessels proliferation and persistent hemorrhagic areas. Therefore, both instrumentation techniques promoted similar pulp response, but different restoration procedures elicited significantly different responses of the dentinpulp complex.

Com o aumento da população mundial, o desenvolvimento de novas fontes e conversores de energia tornou-se uma necessidade. As células a combustível mostram-se como uma alternativa viável devido principalmente a duas razões, sua alta eficiência e a utilização de combustíveis renováveis. No presente trabalho se estuda a influência da temperatura de operação e o conteúdo de álcali no combustível sobre a densidade de potencia para uma célula a combustível de glicerol direto. Como combustível foi utilizado uma solução de glicerol:KOH (1M:xM, x=0, 1, 3, 5), como membranas foram utilizados filmes de polibencimidazol impregnado com ácido fosfórico (PBI/H3PO4, relação molar 1:11) ou 1-hexil-3-metilimidazol trifluorometanosulfonato (PBI/HMI-Tf relação molar 1:1.5), e finalmente, nano partículas de Pt suportadas em carbono (60% w/w) como catalizador no ânodo e no cátodo. Em geral, o incremento da temperatura e conteúdo de álcali no combustível mostra um efeito favorável na densidade de potencia do sistema. Numa célula a combustível unitária de glicerol direto utilizando membranas de PBI/ H3PO4 e PBI/HMI-Tf foram obtidas densidades de potencia de 0.54mW.cm-2 a 175°C e 0.599mW.cm-2 a 130°C, respectivamente, para uma solução de glicerol de (1M); enquanto que, para uma solução com um conteúdo maior de álcali, glicerol:KOH (1M:5M), foram obtidas densidades de potencia maiores, 44.1mW.cm-2 a 175°C e 29mW.cm-2 a 130°C, respectivamente. O efeito combinado do incremento da temperatura e concentração de álcali no combustível mostra um efeito maior em relação ao efeito só da temperatura. / With the increasing world population, the development of new energy sources or energy converters has become a necessity. Fuel cells show up as a viable alternative due mainly to two reasons, their high efficiency and the use of renewable fuels. In the present work we study the influence of operating temperature and alkali content in the fuel on the power density for a direct glycerol fuel cell. A glycerol:KOH (1M: xM, x = 0, 1, 3, 5) solution was used as fuels, as membranes were used polibencimidazol films impregnated with phosphoric acid (PBI/H3PO4, molar ratio of 1:11) or 1-hexyl-3-methylimidazolium trifluoromethanesulfonate (PBI/HMI-Tf), and finally, Pt nanoparticles supported on carbon (60% w / w) as catalyst in the anode and cathode. In general, increasing the temperature and alkali content in the fuel shows a favorable effect in the system power density. In a direct glycerol fuel cell using PBI/H3PO4 and PBI /HMI-Tf membranes were obtained power density of 0.54mW.cm-2 at 175°C and 0.599mW.cm-2 at 130°C, respectively, for a 1M glycerol solution; while for a glycerol solution with a higher content of alkali, glycerol:KOH (1M: 5M), were obtained higher power densities, 44.1mW.cm-2 at 175 ° C and 29mW.cm-2 at 130 ° C, respectively. The combined effect of increased temperature and alkali concentration in the fuel shows a greater effect compared to the effect of temperature only.

Depuis les années 2000 le domaine de l’organocatalyse asymétrique est en plein développement comme le montre le nombre croissant de publications sur le sujet. Durant cet essor un grand nombre d’organocatalyseurs a été développé, ils se classent en quatre catégories : les catalyseurs de transfert de phase, les bases de Lewis, les bases de Brønsted et les acides de Brønsted. Appartenant à cette dernière catégorie, les acides phosphoriques chiraux font partie des acides de Brønsted les plus populaire. Leurs premières utilisations en organocatalyse asymétrique remontent à 2004 où des acides phosphoriques dérivés du BINOL furent utilisés par Terada et Akiyama pour catalyser des réactions de Mannich de manière hautement énantiosélective. Depuis le champ d’application des acides phosphoriques s’est considérablement étendu et aujourd’hui environ 90 réactions différentes peuvent être catalysées efficacement par ces acides. En parallèle de ce développement des équipes ont commencé à apporter des modifications structurales aux acides phosphoriques dans le but d’étendre encore leur champ d’application. L’une des approches consiste à modifier le squelette carboné afin de modifier l’organisation spatiale de l’encombrement stérique chiral autour du phosphore. Le travail présenté dans ce manuscrit décrit l’élaboration et l’utilisation en catalyse d’une nouvelle famille d’acides phosphoriques à chiralité planaire basée sur un motif [3,3]paracyclophane. L’étude commence par la modélisation par calculs DFT de différents paracyclophanes dans le but d’évaluer la tension de cycle et la barrière de rotation imprimer à la structure en fonction de l’espaceur utilisé. Trois espaceurs sont sélectionnés pour des essais en synthèse : le -CH2-NTs-CH2-, le 1,8-naphtalènediyle et le 1,1’-ferrocènediyle. Les synthèses de trois bisphénols comportant les motifs précédents sont réalisées. Les bisphénol comportant les espaceurs -CH2-NTs-CH2-, le 1,8-naphtalènediyle n’ont pas pu être transformés en acides phosphoriques. En revanche il a été possible d’obtenir une nouvelle famille d’acides phosphoriques à chiralité planaire comportant le motif 1,1’-ferrocènediyle.Par la suite une méthode de synthèse permettant la variation facile des substituants aromatiques a été mise en place ainsi qu’une méthode de séparation de diastéréoisomères à l’aide d’un auxiliaire chiral afin d’obtenir des acides phosphoriques énantiopurs. Une famille de 6 acides phosphoriques a ainsi pu être synthétisée. Ces nouveaux acides ont ensuite été testés en organocatalyse asymétrique. La réaction de réduction par des esters de Hantzsch de quinoléines substituées en position 2 a servi de réaction test. Après sélection du meilleur acide, une étude sur l’influence de l’ester de Hantzsch a été menée conduisant à une forte augmentation de l’énantiosélectivité de la réaction. Enfin le champ d’application de la réaction a été explorer et des excès énantiomériques atteignant 92% ont pu être atteints. D’autres modifications structurales peuvent être apportées à cette nouvelle structure comme par exemple le remplacement du motif 1,1’-ferrocènediyle par le motif 1,8-dibromobiphénylènyl. Une influence non négligeable de l’espaceur sur les performances du catalyseur a pu être ainsi observée.L’étude a montré le potentiel de cette nouvelle famille d’acide phosphorique en organocatalyse asymétrique. Cette nouvelle famille va donc pouvoir être utilisée pour développer de nouvelle réaction énantiosélectives et ce dans le domaine de l’organocatalyse ou bien dans celui de la catalyse organométallique en utilisant le phosphate comme contre-ion chiral. / During the first decade of the century the organocatalysis has known an intense development shown by the increasing number of publications on the subject. This development led to the apparition of a wide number of different organocatalysts. These catalysts can be sorted in three categories: the phase transfer catalysts, the Lewis bases, the Brønsted bases and the Brønsted acids. One of the most used types of organocatalysts belonging to the latter category are the chiral phosphoric acids (CPA). The first use of these CPAs as organocatalysts was published in 2004 by Terada and Akiyama. They independently reported two Mannich-type reactions catalysed by BINOL-derived CPAs with high levels of enatioselectivity. Since then CPAs appeared as versatile catalysts and to this date more than 90 different reactions can be catalysed in a highly énantiosélective manner by these acids. Meanwhile some researchers began to modify the original BINOL-based phosphoric acids so as to broaden their scope. One possible approach consists in changing the chiral backbone to change the spatial organisation of the chiral environment. The work reported in this manuscript describe the design, the synthesis and the use in organocatalysis of a new planar chiral phosphoric acids based on a [3,3]paracyclophanes scaffold. This study begins with the DFT modelling of a series of paracyclophanes in order to evaluate the ring strain and rotation barrier induced by the nature of different tethering units. Three tethers have been selected for synthesis trials: the -CH2-NTs-CH2-, the 1,8-naphtalenediyl and the 1,1’-ferrocenediyl. Three different bisphenols each one embedding one of the three tethers mentioned above have been synthesised. It was not possible to turn the -CH2-NTs-CH2- and the 1,8-naphtalenediyl-based bisphenols into the corresponding phosphoric acids. But the 1,1’-ferrocenediyl-based bisphenol was successfully cyclised into the desired planar chiral phosphoric acid. Subsequently a synthetic pathway allowing an easy variation of the aryl substituents has been developed together with the use of a chiral auxiliary to obtain the planar CPAs in an enantiopure way. By this method 6 different CPAs have been synthesised. The efficiency in asymmetric organocatalysis of these new planar CPAs was investigated. The reduction of 2-substituted quinolines by Hantzsch esters was used as a benchmark reaction. After having identified the best CPA, the role of the Hantzsch ester has been investigated leading to an important improvement of the enantioselectivity of the reaction. Eventually, the scope of the reaction has been explored and e.e.’s up to 92% have been reached. Some other structural modifications of the structure can be made such as the replacement of the 1,1’-ferrocenediyl unit by a 1,8-dibromobiphenylenyl. A non-negligible influence of the tether has been observed on the catalyst behaviour. The study has demonstrated the potential of this new class of organocatalyst in asymmetric catalysis. These planar CPAs will then be used in the developpement of new énantiosélective reaction in the domain of organocatalysis or in the domain of organometallic catalysis by using the phosphate as a chiral counter-ion

As microalgas vêm sendo utilizadas na área ambiental nos processos de biomitigação de CO2, uma vez que o utilizam em seu metabolismo para produzirem biomassa celular, a qual pode ser utilizada para fins nutricional e comercial. Neste sentido, o presente trabalho teve como objetivo a obtenção de oligossacarídeos prebióticos oriundos de biomassa microalgal por meio de hidrólise fosfórica em diferentes condições moderadas de pH e termopressurização. Foi utilizada biomassa de um cultivo utilizado no sistema de tratamento de efluente gasoso de uma churrascaria de Curitiba, comparativamente com duas biomassas comerciais, Chlorella vulgaris e Spirulina platensis. Foram realizadas análises microscópicas e físico-químicas para a caracterização das biomassas, tais como umidade, cinzas, teor de carboidratos, lipídeos e proteínas. A partir da massa lipídica total foram realizadas transesterificações alcalinas e os resultados analisados por métodos cromatográficos, antes e após clarificação dos ésteres metílicos. A título de comparação inicial com as biomassas in natura, as biomassas passaram por pré-tratamentos: remoção dos lipídeos com organossolventes, purificação da parede celular com detergente SDS (Sódio Dodecil Sulfato) e recuperação do resíduo polimérico extraído pelo detergente. Estas biomassas derivadas bem como as integrais foram hidrolisadas em termopressurizador a 4,5 atm (156 oC), utilizando ácido fosfórico a pH 2,0 ou controles com água (solvólise). Adicionalmente foram realizados ensaios enzimáticos com α-amilase e β-1,3 glucanase nos oligossacarídeos resultantes dos hidrolisados fosfóricos das biomassas in natura. Com as três biomassas de microalgas in natura foi realizado planejamento fatorial 32, frente às variáveis ácido fosfórico (pH 2,5, 2,0, e 1,5) e pressão atmosférica (3 atm – 147 oC, 4,5 – 156 oC e 6,0 atm – 175 oC). Para todos os hidrolisados foram analisados pH após a hidrólise, teor de açúcar redutor e de açúcar total e perfil cromatográfico. Os oligossacarídeos obtidos foram utilizados como fonte de carbono para o cultivo de microrganismos probióticos, Bifidobacterium animalis e Lactobacillus casei, para avaliação do crescimento, pH e produção de ácidos graxos de cadeia curta (AGCC). Os resultados indicaram que apesar de ter sido inoculada uma cepa de C. vulgaris no sistema de fotobiorreatores de mitigação de CO 2 da churrascaria, não se instalou um cultivo puro e, portanto, foi denominado de mescla Devons. O componente majoritário para todas as biomassas foi proteína, sobretudo para S. platensis (59,5 %). As transesterificações alcalinas mostraram a eficiência no processo, indicando semelhança no perfil da cromatografia gasosa da mescla Devons e C. vulgaris. O tratamento com SDS mostrou maior eficiência na remoção de proteínas, sobretudo em S. platensis. As hidrólises das biomassas pré-tratadas mostraram maior teor de oligossacarídeos na amostra in natura para mescla Devons, deslipidificada e tratada com SDS para C. vulgaris e semelhança entre a in natura e os dois primeiros tratamentos para S. platensis. Os resultados dos ensaios enzimáticos indicaram predominância de oligossacarídeos oriundos de laminarina (β-1,3 glucana), portanto prebióticos e resistentes à ação amilásica do trato gastrointestinal (TGI) superior. Os resultados do planejamento fatorial mostraram que a biomassa in natura de S. platensis foi a que apresentou os melhores resultados de hidrólise em quantidade de açúcar liberado, seguida da biomassa de mescla Devons e C. vulgaris. As melhores condições de produção e pureza de oligossacarídeos foram próximas ao ponto central do planejamento fatorial. Os cultivos dos probióticos utilizando os hidrolisados fosfóricos permitiu o crescimento das baterias benéficas (Lactobacillus e Bifidobacterium), e diferenças no pH, bem como na produção de AGCC, sobretudo ácido lático, monitorado por cromatografia líquida. Portanto, este trabalho mostra que foram produzidos oligossacarídeos prebióticos a partir do tratamento fosfórico da biomassa de microalgas, resultando uma nova aplicação em potencial de tal biomassa formada a partir do CO2 e outros componentes voláteis presentes no efluente gasoso da churrascaria. / Microalgae have been utilized in the environmental area in CO2 biomitigation processes as they use it in their metabolism for the production of cellular biomass, which can then be utilized for nutritional and commercial purposes. Within this scope, the current research elected as the main objective, the obtention of nutraceutical oligosaccharides from microalgae biomasses through a phosphoric acid hydrolysis under different and moderated pH and thermopressurization conditions. One biomass, coming from a gaseous effluent treatment system from a steakhouse was compared to commercial biomasses, Chlorella vulgaris e Spirulina platensis. Microscopic and physicochemical analyses were carried for these biomasses characterization, namely moisture, ashes, carbohydrates, lipids and protein contents. Alkaline methyl transesterifications were realized in the total lipid fractions and then the corresponding products analyzed by chromatographic methods. As compared to the native biomasses, they were subjected to pretreatments: organic solvents removal of lipids, cell wall purification with detergent SDS (Sodium Dodecyl Sulphate) and recovery of polymeric molecules of the later extracts. These derived biomasses fractions, as well as the whole ones were partially or totally hydrolyzed with thermopressurization at 4.5 atm (156 °C) using diluted phosphoric acid at pH 2 or with water as controls (solvolysis). Enzyme assays were further performed with α- amylase and β-1,3 glucanase in the phosphoric acid hydrolyzed oligosaccharides from native biomasses. A 32 factorial design was carried out with the three samples of whole microalgae biomasses, considering the variables phosphoric acid pH (2.5, 2.0, e 1.5) and atmospheric pressure (3 atm – 147 oC, 4.5 – 156 oC and 6.0 atm – 175 o C). For all hydrolysates were analyzed pH after hydrolysis, total and reducing sugar contents and chromatographic profiles. The resulting oligosaccharide samples were offered as carbon source for the culture of probiotic microorganisms Bifidobacterium animalis e Lactobacillus casei for the evaluation of bacterial growth and short chain fatty acids (SCFAs) production. Overall results indicated that irrespective to the pure native of the C. vulgaris inoculum into the CO2 mitigation system of the steakhouse, a pure massive biomass did not result and hence the designation of Devons’ blend for. The major component of microalgae biomasses was protein, above all for S. platensis (59.5 %). Alkaline transesterification showed the efficiency of the process, indicating similarity among the methyl esters arising either from C. vulgaris or the Devons’ blend as analyzed by gas chromatography. SDS treatment was more efficient for protein removal in the case of S. platensis biomass. The pretreated biomasses once hydrolysed displayed higher oligosaccharide contents for the Devons’ blend native, C. vulgaris delipidified and SDS-treated sample as well some similarity between native and both pretreatments in the case of S. platensis. The enzymatic assay indicated predominance of laminarin oligosaccharides (β-1,3 glucan), therefore prebiotics are resistants to amylasic action in upper gastroinstestinal tract. The factorial design showed that the particular S. platensis native biomass led to the best result of hydrolysis to reducing simple and oligosaccharidic sugars, then decreasingly followed by the Devons’ blend and C. vulgaris and the best conditions for the production and purity of the oligosaccharides were close to the central point of the factorial design. Probiotic cultures from the phosphoric acid hydrolysates allowed the Lactobacillus and Bifidobacterium, beneficial bacteria growth, pH differences and short chain fatty acids production, above all, lactic acid, as monitored by high performance liquid chromatography. Therefore, this research indicated the feasibility of nutraceutical or prebiotic oligosaccharide production from microalgae biomasses, thus revealing a novel technological destination for these particular biomasses and fractions, once formed at the expense of CO2 and other volatile components from the gaseous effluent from a steakhouse.

La thèse est consacrée à la développement de méthodes efficaces pour la synthèse d'une nouvelle classe d'intrinsèquement chiral calix[4]arènes contenant du phosphore, phosphines et acides phosphoriques avec une certaine disposition mutuelle des groupes fonctionnels sur le bord inférieur du macrocycle, avec un potentiel activité catalytique. La façon optimale fot la synthèse de calix[4]arènes contenant du phosphore par la substitution progressive des hydroxyles phénoliques a été développé afin de concevoir des intrinsèquement chiral calix[4]arènes avec des types de remplacement ABHH et ABCH au bord inférieur du macrocycle. En utilisant ces techniques, la synthèse de la six catalyseurs et efficaces avec chiralité planaire a été réalisée. En utilisant des études de diffraction des rayons X a permis d'étudier la localisation spatiale des groupes fonctionnels. L'utilisation de la réaction de Mitsunobu autorisé à fournir une synthèse de la nouvelle "poche" -comme ligands - calix[4]arènes portant des fragments ferrocényle-phosphines chirales. L'efficacité des nouveaux ligands phosphine synthétisés a été confirmé par l'exemple du modèle de réaction Tsuji-Trost. intéressante dépendance du niveau de sélectivité de la taille du cation de métal de base ajoutée, en raison de l'effet de ligand de chélation du supramoléculaire a été observée. Calix[4]arènes acides phosphoriques a d'abord été appliqués comme organocatalyseurs la série de réactions modèles: aza-Diels-Alder, aza-Mukayiama réaction asymétrique et réaction d'ouverture d'époxydes anneau. Il a été constaté que la plupart des composés synthétisés présentent un degré notable de activitydue catalytique à des caractéristiques de chiralité interne. / The thesis is devoted to the developing of effective methods for the synthesis of new class of inherently chiral phosphorus-containing calix[4]arenes, phosphines and phosphoric acids with a certain mutual arrangement of functional groups on the lower rim of the macrocycle, with potential catalytic activity. The optimal way fot the synthesis of phosphorus-containing calix[4]arenes by the stepwise substitution of the phenolic hydroxyls was developed in order to design inherently chiral calix[4]arenes with ABHH and ABCH replacement types at the lower rim of the macrocycle. By using these techniques, synthesis of six analogues of known and effective catalysts with planar chirality was performed. Using X-ray diffraction studies allowed to investigate spatial location of functional groups. Using of Mitsunobu reaction allowed to provide synthesis of the new "pocket"-like ligands - calix[4]arenes bearing chiral ferrocenyl-phosphines moieties. The effectiveness of the synthesized new phosphine ligands was confirmed by the example of the model Tsuji-Trost reaction. Interesting dependence of the selectivity level on the metal cation size of added base, due to chelation effect of supramolecular ligand was observed. Calix[4]arenes phosphoric acids was first applied as organocatalysts the series of model reactions: aza-Diels-Alder reaction, aza-Mukaiyama asymmetric reaction and epoxides ring opening reaction. It was found that most of the synthesized compounds exhibit a noticeable level of catalytic activitydue to features of internal chirality.

Com o aumento da população mundial, o desenvolvimento de novas fontes e conversores de energia tornou-se uma necessidade. As células a combustível mostram-se como uma alternativa viável devido principalmente a duas razões, sua alta eficiência e a utilização de combustíveis renováveis. No presente trabalho se estuda a influência da temperatura de operação e o conteúdo de álcali no combustível sobre a densidade de potencia para uma célula a combustível de glicerol direto. Como combustível foi utilizado uma solução de glicerol:KOH (1M:xM, x=0, 1, 3, 5), como membranas foram utilizados filmes de polibencimidazol impregnado com ácido fosfórico (PBI/H3PO4, relação molar 1:11) ou 1-hexil-3-metilimidazol trifluorometanosulfonato (PBI/HMI-Tf relação molar 1:1.5), e finalmente, nano partículas de Pt suportadas em carbono (60% w/w) como catalizador no ânodo e no cátodo. Em geral, o incremento da temperatura e conteúdo de álcali no combustível mostra um efeito favorável na densidade de potencia do sistema. Numa célula a combustível unitária de glicerol direto utilizando membranas de PBI/ H3PO4 e PBI/HMI-Tf foram obtidas densidades de potencia de 0.54mW.cm-2 a 175°C e 0.599mW.cm-2 a 130°C, respectivamente, para uma solução de glicerol de (1M); enquanto que, para uma solução com um conteúdo maior de álcali, glicerol:KOH (1M:5M), foram obtidas densidades de potencia maiores, 44.1mW.cm-2 a 175°C e 29mW.cm-2 a 130°C, respectivamente. O efeito combinado do incremento da temperatura e concentração de álcali no combustível mostra um efeito maior em relação ao efeito só da temperatura. / With the increasing world population, the development of new energy sources or energy converters has become a necessity. Fuel cells show up as a viable alternative due mainly to two reasons, their high efficiency and the use of renewable fuels. In the present work we study the influence of operating temperature and alkali content in the fuel on the power density for a direct glycerol fuel cell. A glycerol:KOH (1M: xM, x = 0, 1, 3, 5) solution was used as fuels, as membranes were used polibencimidazol films impregnated with phosphoric acid (PBI/H3PO4, molar ratio of 1:11) or 1-hexyl-3-methylimidazolium trifluoromethanesulfonate (PBI/HMI-Tf), and finally, Pt nanoparticles supported on carbon (60% w / w) as catalyst in the anode and cathode. In general, increasing the temperature and alkali content in the fuel shows a favorable effect in the system power density. In a direct glycerol fuel cell using PBI/H3PO4 and PBI /HMI-Tf membranes were obtained power density of 0.54mW.cm-2 at 175°C and 0.599mW.cm-2 at 130°C, respectively, for a 1M glycerol solution; while for a glycerol solution with a higher content of alkali, glycerol:KOH (1M: 5M), were obtained higher power densities, 44.1mW.cm-2 at 175 ° C and 29mW.cm-2 at 130 ° C, respectively. The combined effect of increased temperature and alkali concentration in the fuel shows a greater effect compared to the effect of temperature only.

Este estudo se propõe a analisar a resposta pulpar de dentes humanos a preparos cavitários de classe V, em função de duas diferentes técnicas de instrumentação e de duas diferentes técnicas de restauração. Para tal, cavidades classe V, nas superfícies vestibulares de 48 pré-molares hígidos de pacientes entre 11 e 25 anos, que estavam em tratamento ortodôntico, foram preparadas e restauradas de acordo com os seguintes grupos experimentais: G 1 (n=24) - preparos cavitários realizados com ponta diamantada em alta rotação, restaurados com guta-percha plastificada, cimento ionômero de vidro e verniz cavitário (G 1A; n=12) ou com técnicas adesivas (sistema restaurador adesivo aplicando-se o condicionamento ácido total) e cimento ionômero de vidro (G 1B; n=12); G 2 (n=24) - preparos cavitários com ponta CVD ativada por ultrassom, restaurados com gutapercha plastificada, cimento ionômero de vidro e verniz cavitário (G 2A; n=12) ou com técnicas adesivas (sistema restaurador adesivo aplicando-se o condicionamento ácido total) e cimento ionômero de vidro (G 2B; n=12); e G 3 (controle; n=4) - dentes que foram extraídos sem a realização de qualquer procedimento. Os preparos cavitários foram realizados mantendo o assoalho da cavidade o mais próximo possível da polpa, no entanto, sem provocar exposição pulpar. Os dentes foram extraídos após três períodos experimentais (imediato, sete e trinta dias após o preparo cavitário), fixados, descalcificados, e processados histologicamente. Cortes teciduais longitudinais seriados de 5 m foram obtidos, corados pelas técnicas de H & E e de Brown & Brenn, e examinados em microscopia ótica. As avaliações morfométricas e por escores foram realizadas e os resultados das mesmas, submetidos, respectivamente, aos testes estatísticos de Mann-Whitney e de Kruskal-Wallis/Dunn, adotando-se um nível de significância de 5%. No período inicial, todos os grupos experimentais (1A, 1B, 2A e 2B) exibiram ligeiro desarranjo da camada odontoblástica vacuolizada e leve invasão da zona acelular de Weil. Não houve diferença entre os grupos experimentais iniciais e o grupo controle. No intervalo de sete dias, pôde-se observar redução da camada odontoblástica, muitos núcleos de odontoblastos aspirados nos túbulos dentinários, alguns espécimes com ausência de pré-dentina e resposta inflamatória aguda com hemorragia. Trinta dias depois, cinco espécimes do total avaliado apresentaram dentina terciária; dois espécimes do grupo 1B apresentaram necrose relacionada com a presença de bactérias nos túbulos dentinários; e os demais mostraram graus variados de inflamação crônica, associados a restaurações adesivas ou a processos de reparo, com proliferação de vasos e persistência de focos de hemorragia. Portanto, os dois tipos de instrumentação cavitária promovem respostas pulpares similares entre si, mas as diferentes técnicas restauradoras promovem efeitos significativamente diferentes sobre o complexo dentinopulpar. / The aim of this study is to analyze the pulp response of human teeth to class V cavity preparation, in function of two different instrumentation and restorative techniques. Class V cavities were made on the buccal surfaces of 48 sound human pre-molars from orthodontic patients from 11 to 25 years, and were divided as follows: G1 (n=24) cavity preparations were made with diamond bur under high speed, restored with either plasticized gutta-percha, glass ionomer cement and surface coated with varnish (G1A) or adhesive protocol (total etch technique and adhesive system application) with glass ionomer filling (G1B); G2 (n=24) cavity preparations were made with diamond CVD point and ultrasonic device, restored with either plasticized gutta-percha, glass ionomer cement and surface coated with varnish (G2A) or adhesive protocol (total etch technique and adhesive system application) with glass ionomer filling (G2B); and control group G3 (n=4) extracted teeth with no previous cavity preparation. All avities were prepared with the cavity floor as close to the pulp as possible, without causing pulp exposure. Teeth extractions were made in three experimental periods (immediate, 7 and 30 days after cavity preparation) and right after extraction they were submitted to histological procedures. Longitudinal tissue serial sections of 5 mm were obtained, H&E and Brown&Brenn stained, and analyzed under optical microscope. Morphometric and score evaluations were carried out and data from both were, respectively, submitted to Mann-Whitney and Kruskal-Wallis/Dunn tests, with 5% significance. Immediately, all experimental groups (1A, 1B, 2A and 2B) exhibited a discrete disorganization of the odontoblastic layer and invasion of the Weil zone. There was no difference between experimental and control groups. At 7-day interval, a decrease of the odontoblastic layer was observed. Many odontoblasts nucleus were seen displaced into the dentinal tubules. Some specimens showed absence of pre-dentine and inflammatory pulp response with hemorrhage. Thirty days later, five specimens presented tertiary dentin formation; two specimens from group 1B presented necrosis coincident with bacteria inside the dentinal tubules; the other specimens showed various degrees of chronic inflammation, associated to adhesive restorations or repair processes, with blood vessels proliferation and persistent hemorrhagic areas. Therefore, both instrumentation techniques promoted similar pulp response, but different restoration procedures elicited significantly different responses of the dentinpulp complex.