La famille des Icacinaceae est une famille de plantes à fleurs possédant un registre fossile important durant le Paléogène, principalement en Amérique du Nord et en Europe. En particulier, des fossiles d’Icacinaceae ont été retrouvés au niveau de cinq sites du Bassin de Paris, principalement sous forme d’endocarpes datant du Thanétien et de l’Yprésien. Ces sites sont donc d’un grand intérêt pour étudier l’impact du maximum thermique de la limite Paléocene-Eocène sur les flores. En premier lieu, un travail sur les fruits actuels a permis de montrer la grande diversité des endocarpes et leurs valeurs en terme de reconnaissance spécifique chez les Icacinaceae. Par ailleurs, une clé d’identification Xper3 accompagne cette étude. L’étude des fossiles du Bassin de Paris a permis de mettre en évidence huit nouvelles espèces appartenant au genre Iodes, une occurrence de Palaeophytocrene et Icacinicarya ainsi que le nouveau genre Icacinanthium décrit à partir d’une fleur et de grains de pollen pris dans de l’ambre. Sur les cinq espèces paléocènes, trois sont retrouvées au niveau des sites de l’Eocène, ce qui démontre au moins une continuité partielle des flores durant le réchauffement climatique. Cependant, une plus grande disparité morphologique est soulignée dans les sites éocènes. L’utilisation de l’ensemble du registre fossile a permis de reconstruire une histoire paléobiogéographique de la famille, en particulier de mettre en évidence une diversification de la famille durant l’Yprésien et plus généralement au cours de l’Eocène. Enfin, une étude de datation phylogénétique a permis de mettre en évidence la diversification d’un clade d’espèces grimpantes à la limite Paléocène-Eocène. Ainsi les différents niveaux d’études sont congruents et montrent que le réchauffement global du Paléocène-Eocène n’est pas un événement catastrophique pour les Icacinaceae, mais plutôt une époque de diversification et d’apports nouveaux par migration, principalement en Hémisphère Nord. / The Icacinaceae family is a group of Angiosperm with a large fossil record, mainly from the North American and European Paleogene. Especially, fossils related to Icacinaceae were found in five sites from the Paris Basin, mainly as endocarp remains, in the Thanetian and Ypresian. Therefore, these sites constitute a good opportunity to study the impact of the global warming at the Paleocene-Eocene boundary in the floras. As a first step, we propose a survey of extant fruits; we show an important diversity of fruit shapes emphasizing the value of this organ in terms of specific assignment. An Xper3 database was built in addition to this study. The study of fossil’s remains from the Paris Basin revealed the presence of eight new species belonging to the genus Iodes, an occurrence of genera Palaeophytocrene and Icacinicarya and a new genus, Icacinanthium, described from a flower and pollen in amber. Among the five species described from the Paleocene, three were present in the Eocene sites, demonstrating at least a partial continuity of the Icacinaceae through the Paleocene-Eocene boundary. However, a greater morphological disparity was underlined in the Eocene sites. The use of all the fossil records allowed us to reconstruct the biogeographic history of the family and especially the diversification of the Icacinaceae during the Ypresian and more generally during the Eocene. Finally, a phylogenetic datating study highlighted a diversification of a climber clade at the Paleocene-Eocene boundary. Therefore, the different levels of studies are congruent and show that the Paleocene-Eocene Thermal Maximum was not a catastrophic event for the Icacinaceae family but rather a diversification event and new contributions by migration, mainly in the Northern Hemisphere.

Fast pyrolysis, the rapid thermal decomposition of organic material in the absence of oxygen, is a process that can be used to convert biomass into liquid fuels and chemicals. When performed at the micro-scale, pyrolysis is useful for characterizing biomass structure, as well as determining the pyrolysis products that can be generated from specific biomass feedstocks. Indeed, microscale pyrolysis coupled with on-line analysis of the pyrolysis vapors by GC/MS, so-called pyrolysis-GC/MS (Py-GC/MS), is a technique that can be used to characterize the structure and composition of the various components of lignocellulosic and microalgal biomass based on their pyrolysate distributions. Pyrolysates produced also provide insight into the range of products that can be expected when biomass feedstocks are subjected to thermal decomposition processes. This dissertation focuses on the Py-GC/MS analysis of lignocellulosic biomass such as sorghum and Scenedesmus sp. microalgae, in addition to high-lignin feedstocks such as walnut shells, coconut shells, olive pits and peach pits. The differences in the pyrolysate distributions among these biomass types are correlated with differences in the structure and composition of the biopolymers, mainly cellulose, hemicellulose and lignin, present in the biomass. Py-GC/MS analysis of lignin extracted from endocarp feedstocks is also emphasized. In addition to biomass and extracted lignin, sinapyl (S) and coniferyl (G) alcohol have been analyzed by Py-GC/MS in order to understand the relationship between the corresponding pyrolysates and sinapyl/coniferyl ratios of lignin present in lignocellulosic biomass.

The Late Hemphillian (latest Miocene or earliest Pliocene, 7-4.5 Ma) Gray Fossil Site in northeastern Tennessee is interpreted to represent a lacustrine paleokarst fed by a river or stream. This research focuses on the morphological and systematic relations of Nyssa endocarps (fruit pits) from the fossil site to extinct and extant Nyssa species. A combination of metric and nonmetric traits allows recognition of a new species: Nyssa grayensis sp. nov. This fossil species shares the most similarities with the extant Nyssa ogeche Bartram ex Marshall from southeast North America and the Eocene fossil Nyssa eolignitica Berry from western Tennessee. Affinities with Nyssa ogeche Bartram ex Marshall suggest a warmer winter climate than the present and periodically fluctuating water levels. Fossil vertebrates (Alligator, Heloderma, Hesperotestudo) and plants (Fossil relatives of Ilex vomitoria, Quercus virginiana, Taxodium, Acer leucoderme) with modern counterparts distributed in areas with mild winters support this interpretation.

Made available in DSpace on 2014-12-17T15:03:27Z (GMT). No. of bitstreams: 1 RafaelM_DISSERT.pdf: 1989956 bytes, checksum: 4d567b87a39f4ad9191e5a5c7decf060 (MD5) Previous issue date: 2011-08-22 / The groundwater quality has been compromised as a result of the intensification of human activities over the years. Groundwater contamination by nitrate is one of the effects of this degradation, a socio-environmental problem that affects many regions of the world and particular the city of Natal (RN). Developing techniques for nitrate removal in water is intended to eliminate or reduce the concentration of this compound, and those that involve biological processes have produced economic and environmental advantages. This study proposes a technology for biological removal of nitrate in water supply for humans, using the endocarp s coconut as a carbon source and bacteria support. The experiments were performed in pilot scale anoxic, testing different areas of the substrate surface. Results showed high rates nitrate removal during the monitoring period, noting the occurrence of denitrification after the beginning of system operation. The best performance was achieved in the treatment system containing substrate surface area increased, indicating that the decrease in the endocarp size contributed to increased bacterial activity, improving the ability to remove nitrate. About the quality analyzed aspects of water, it was found that the proposed technology has the potential water use for human consumption / A qualidade da ?gua subterr?nea vem sendo cada vez mais comprometida como consequ?ncia da intensifica??o das a??es antr?picas ao longo dos anos. Um dos efeitos dessa degrada??o ? a contamina??o dos mananciais subterr?neos por nitrato, um problema s?cio-ambiental que atinge diversas regi?es do mundo e, em particular, a cidade do Natal (RN). T?cnicas para remo??o de nitrato em ?guas t?m sido desenvolvidas a fim de eliminar, ou reduzir, a concentra??o deste composto, sendo que, as que envolvem processos biol?gicos t?m apresentado vantagens econ?micas e ambientais. Esse estudo prop?e uma tecnologia de remo??o biol?gica do nitrato em ?gua de abastecimento humano, utilizando o endocarpo de coco como fonte de carbono e suporte bacteriano. Os experimentos foram realizados em c?maras an?xicas em escala piloto, testando diferentes ?reas superficiais do substrato. Os resultados mostraram elevadas taxas de remo??o de nitrato ao longo do per?odo de monitoramento, observando a ocorr?ncia da desnitrifica??o logo ap?s o in?cio do funcionamento do sistema. O melhor desempenho foi alcan?ado no sistema de tratamento contendo substrato de maior ?rea superficial, indicando que a diminui??o no tamanho do endocarpo contribuiu com o aumento da atividade bacteriana, melhorando a capacidade de remo??o de nitrato. Quanto ? qualidade da ?gua analisada, verificou-se que a tecnologia proposta tem potencialidade de uso da ?gua para consumo humano

Made available in DSpace on 2014-12-17T14:06:58Z (GMT). No. of bitstreams: 1 LuizCFS.pdf: 3453741 bytes, checksum: a917d4da21cccce053bc103345ba7ee6 (MD5) Previous issue date: 2008-07-10 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This research is about the use of the coconut?s endocarp (nucifera linn) and the waste of derivatives of wood and furniture as raw material to technological use. In that sense, the lignocellulosic waste is used for manufacture of homogeneous wood sheet agglomerate (LHWS) and lignocellulosic load which take part of a polymeric composite with fiber glass E (GFRP-WC). In the manufacturing of the homogeneous wood sheet agglomerate (LHWS), it was used mamona?s resin as waste s agglutinating element. The plates were taken up in a hydraulic press engine, heated, with temperature control, where they were manufactured for different percentage of waste wood and coconuts nuc?fera linn. Physical tests were conducted to determine the absorption of water, density, damp grade (in two hours and twenty-four hours), swelling thickness (in two hours and twenty-four hours), and mechanical tests to evaluate the parallel tensile strength (internal stick) and bending and the static (steady) flexural. The physical test?s results indicate that the LHWS can be classified as bonded wood plate of high-density and with highly water resistant. In the mechanical tests it was possible to establish that LHWS presents different characteristics when submitted to uniaxial tensile and to the static (steady) flexural, since brittle and elasticity module had a variation according to the amount of dry endocarp used to manufacture each trace of LHWS. The GFRP-WC was industrially manufactured by a hand-lay-up process where the fiber glass E was used as reinforcement the lignocellul?sic?s waste as load. The matrix was made with ortofitalic unsaturated polyester resin. Physical and mechanical tests were performed in presence of saturated humidity and dry. The results indicated good performance of the GFRP-WC, as traction as in flexion in three points. The presence of water influenced the modules obtained in the flexural and tensile but there were no significant alteration in the properties analyzed. As for the fracture, the analysis showed that the effects are more harmful in the presence of damp, under the action of loading tested, but despite this, the fracture was well defined starting in the external parts and spreading to the internal regions when one when it reaches the hybrid load / Na presente pesquisam-se a utiliza??o do endocarpo do cocos nuc?fera linn e o res?duo de derivados de madeira e de m?veis como mat?ria-prima para uso tecnol?gico. Nesse sentido, usam-se esses res?duos lignocelul?sico na fabrica??o de chapa de madeira aglomerada homog?nea (CHMC) e, como carga, em comp?sito polim?rico refor?ado com fibra de vidro E (PHFV-MC). Na fabrica??o da chapa de madeira aglomerada homog?nea (CHMC) usou-se a resina ? base de mamona como elemento aglutinante dos res?duos. As chapas foram conformadas em uma prensa hidr?ulica aquecida com controle de temperatura, onde as mesmas foram fabricadas para diferentes percentuais dos res?duos de madeira e do cocos nuc?fera linn. Foram realizados ensaios f?sicos para a determina??o de absor??o de ?gua, densidade, do teor de umidade (em duas horas e vinte e quatro horas), inchamento de espessura (em duas horas e vinte e quatro horas), e ensaios mec?nicos para a determina??o da resist?ncia ? tra??o paralela (ades?o interna) e o ensaio de flex?o est?tica. Os resultados obtidos nos ensaios f?sicos indicam que a CHMC pode ser classificada como chapa de madeira aglomerada de alta densidade e que suporta bem a presen?a de ?gua. Nos ensaios mec?nicos foi poss?vel constatar que a CHMC apresenta caracter?sticas distintas quando submetida ? for?a de tra??o uniaxial e ? flex?o est?tica, uma vez que os m?dulos de ruptura e de elasticidade variaram em fun??o da quantidade do endocarpo seco usado para fabricar cada tra?o da CHMC. A PHFV-MC foi fabricada industrialmente por meio do processo hand-lay-up onde a fibra de vidro-E foi usada como refor?o e os res?duos lignocelul?sicos, como carga. A matriz foi ? base de resina poli?ster ortofit?lica insaturada. Foram realizados ensaios f?sicos e mec?nicos em presen?a de umidade saturada e a seco. Os resultados indicaram um bom desempenho da PHFV-MC, tanto na tra??o quanto na flex?o em tr?s pontos. A presen?a de ?gua influenciou os m?dulos obtidos na flex?o e na tra??o, mas n?o alterou significativamente as propriedades analisadas. Quanto ? fratura, a an?lise mostrou que os efeitos s?o mais danosos em presen?a da umidade, sob a a??o dos carregamentos analisados, mas, apesar disto, a fratura se mostrou bastante caracterizada, iniciando nas regi?es externas e se propagando para as regi?es internas quando atinge a carga h?brida