<p>The rationale of this study is to apply light stable isotope chemistry towards investigations that require temporally high-resolution data. High-resolution (or high sampling frequency) data sets, are critical for testing environmental and/or paleoenvironmental hypotheses that seek to explain processes occurring over rapid or short time intervals. The investigation of climate variation (e.g., seasonality, El Niño, deglaciation), animal migration and physiology, and disturbance ecology (e.g., fire, flooding) benefits from the recovery of proxy information at decadal to subannual resolutions. The type of material used also dictates a spatial scale. Herein are presented four studies that utilize high-resolution light stable isotope profiles with contrasting temporal and spatial scales. The first study employs advances in three-dimensional computer-controlled micromilling to recover ~daily to weekly deposited carbonate from small (~1 cm) mollusc shells. Stable oxygen isotope values from freshwater mollusc shells are predictably related to the local environment of growth using previously published temperature-fractionation relationships, providing a paleoclimate record of temperature and precipitation. The second study investigates variation in stable carbon isotope values from Aplodinotus grunniens otoliths, for which high-resolution patterns were critical in assessing metabolic rate as the governing control. The third study employs high-resolution stable oxygen and carbon isotope values to determine chinook salmon (Oncorhynchus tshawytscha) seasonal and ontogenetic migration in Lake Ontario and its tributaries. Lastly, high-resolution stable hydrogen and carbon isotope values of chitin derived from Mexican free-tailed bat (Tadarida brasiliensis) guano are presented, providing a record of abrupt climate change. Thus, this thesis reports on promising new research avenues for paleoclimatology, paleoecology, and modern ecology.

<p>The rationale of this study is to apply light stable isotope chemistry towards investigations that require temporally high-resolution data. High-resolution (or high sampling frequency) data sets, are critical for testing environmental and/or paleoenvironmental hypotheses that seek to explain processes occurring over rapid or short time intervals. The investigation of climate variation (e.g., seasonality, El Niño, deglaciation), animal migration and physiology, and disturbance ecology (e.g., fire, flooding) benefits from the recovery of proxy information at decadal to subannual resolutions. The type of material used also dictates a spatial scale. Herein are presented four studies that utilize high-resolution light stable isotope profiles with contrasting temporal and spatial scales. The first study employs advances in three-dimensional computer-controlled micromilling to recover ~daily to weekly deposited carbonate from small (~1 cm) mollusc shells. Stable oxygen isotope values from freshwater mollusc shells are predictably related to the local environment of growth using previously published temperature-fractionation relationships, providing a paleoclimate record of temperature and precipitation. The second study investigates variation in stable carbon isotope values from Aplodinotus grunniens otoliths, for which high-resolution patterns were critical in assessing metabolic rate as the governing control. The third study employs high-resolution stable oxygen and carbon isotope values to determine chinook salmon (Oncorhynchus tshawytscha) seasonal and ontogenetic migration in Lake Ontario and its tributaries. Lastly, high-resolution stable hydrogen and carbon isotope values of chitin derived from Mexican free-tailed bat (Tadarida brasiliensis) guano are presented, providing a record of abrupt climate change. Thus, this thesis reports on promising new research avenues for paleoclimatology, paleoecology, and modern ecology.

In business buildings, great part of the required power is spent on the air conditioning of internal settings. The transparent façades on such buildings are greatly significant on such matters, since a notable percentage of the thermal exchanges happen trough these elements. This paper structures an overview on the historical changes on the use of glasses on business buildings in the city of Porto Alegre, state of Rio Grande do Sul, highlighting the contemplation of the aspect of thermal and luminosity control on built environments. For each historical period, it s notable that the availability of different types of glasses on the market, chosen by architects, changes, resulting in diverse thermo-environmental and visual behaviors. The present paper was based on historical data, ranging from the period of 1992 to 2008, allowing analyses based on the performance of each alternative, taking into consideration the glasses spectrophotometric characteristics, solar factor values, visible transmission and thermal transmittance and the relation within the amount of energy required for cooling and heating the considered settings. 25 buildings were analyzed in the city and, from those, seven were selected for being considered to be representative of their period, with different solutions on their glass coverings. The data obtained was the basis for comparing their performances, on the various solar orientations, with that of a common glass. A trend of specifying lenses less reflective has been observed, with an increase in the amount of energy inflowing the rooms; and insulated glasses also, that hamper trade among environments. / Em edifícios comerciais, grande parte da energia necessária é gasta para o condicionamento térmico dos ambientes. Os fechamentos transparentes destes edifícios têm grande importância neste fato, pois significativo percentual das trocas térmicas ocorre através destes elementos. Este trabalho faz uma avaliação das mudanças históricas na utilização de vidros em prédios comerciais na cidade de Porto Alegre no estado do Rio Grande do Sul, evidenciando a consideração do aspecto do controle térmico e luminoso dos ambientes. Para cada período histórico, observa-se que as opções de vidros disponíveis no mercado, e especificados, são diferentes, resultando em comportamentos ambientais térmicos e visuais também diferentes. Este trabalho foi baseado em dados históricos do período de 1992 a 2009, permitindo uma análise dos desempenhos de cada solução, considerando-se as características espectrofotométricas dos vidros, valores de fator solar, transmissão no visível e transmitância térmica, e sua relação com a quantidade de energia necessária para refrigerar e aquecer suas salas. Foram analisados 25 edifícios comerciais na cidade, e destes, foram selecionadas sete considerados representativos para sua época, com soluções diferentes em seus envidraçamentos. Os dados obtidos serviram de base para comparar suas performances, nas devidas orientações solares, com as de um vidro comum. Observou-se que há uma tendência pela especificação de vidros menos refletivos, favorecendo o aumento da quantidade de energia que adentra as salas, e também de vidros insulados, que dificultam as trocas térmicas entre ambientes.

Orientador: Massao Ionashiro / Banca: Adelino Vieira de Godoy Netto / Banca: Éder Tadeu Gomes Cavalheiro / Banca: Maria Inês Gonçalves Leles / Banca: Salvador Claro Neto / Resumo: Foram sintetizados em solução aquosa os compostos [Ln(3-MeO-Bz)3].nH2O, sendo que Ln representa os lantanídeos trivalentes e Y(III) e 3-MeO-Bz representa o 3-metoxibenzoato. Os compostos foram sintetizados por adição estequiométrica do ligante nas respectivas soluções de cloretos ou nitratos de lantanídeos, sob agitação. A precipitação dos compostos foi instantânea e a caracterização foi realizada utilizando-se de métodos convencionais como: difratometria de raios X pelo método do pó, espectroscopia de absorção na região do infravermelho, análise elementar e as técnicas termoanalíticas TG/DTG (termogravimetria / termogravimetria derivada), TG - DTA (termogravimetria e análise térmica diferencial simultânea) e DSC (calorimetria exploratória diferencial). Estas técnicas forneceram informações sobre desidratação, modos de coordenação, comportamento térmico, composição e estrutura dos compostos sintetizados. Com os resultados das curvas TG e da complexometria, pôde-se estabelecer a fórmula geral de cada composto sintetizado. Pela análise dos difratogramas de raios X foi observado que todos os compostos sintetizados são cristalinos sem evidência de isomorfismo. A observação dos espectros na região do infravermelho sugeriram uma coordenação quelante-bidentada do ligante aos respectivos centros metálicos. As curvas TG - DTA e DSC forneceram informações inéditas e importantes sobre o comportamento e a decomposição térmica dos compostos sintetizados. / Abstract: Solid state compounds of the type [Ln(3-MeO-Bz)3].nH2O, where Ln stands for trivalent La to Lu and Y(III) and 3-MeO-Bz is 3-methoxybenzoate, have been synthesized. The solid state compounds were prepared by stoichiometric addition slowly of the ligand solution to the respective metal chloride or nitrate solutions, with continuous stirring. The precipitation of the compounds was instantaneous and the characterization was performed using conventional methods such as: X-ray powder diffraction, infrared spectroscopy, elemental analysis, complexometry, simultaneous thermogravimetry and differential thermal analysis (TG-DTA), derivative thermogravimetry (DTG), differential scanning calorimetry (DSC). These techniques provided information about dehydration, coordination modes, thermal behavior, composition and structure of synthesized compounds. From TG curves and complexometry results, a general formula could be established for these compounds in the solid state. The X-ray powder patterns pointed out that the synthesized compounds have a crystalline structure without evidence concerning to the formation of isomorphous series. The infrared spectroscopy data suggest that 3- methoxybenzoate acts as a chelating bidentate ligand towards the metal ions considered in this work. The TG - DTA and DSC curves provided new and important information concerning the thermal behaviour and thermal decomposition of these compounds. / Doutor

Conselho Nacional de Desenvolvimento Científico e Tecnológico / This works investigated the curing reaction of epoxidized oleic acid starshaped with different anhydrides, forming product as oligoésteres and polyesters. Oleic acid modified was obtained by esterification of oleic acid with an aminoalcohol to the resulting aminoester, followed by epoxidation of the double bond. The polymerization reactions were carried out from the opening of epoxy rings in the presence of different cyclic acid anhydrides: phthalic anhydride (PA), maleic anhydride (MA) and succinic anhydride (SA). The structures of the products in these reactions were elucidated by nuclear magnetic resonance (NMR) 1H and 13C and infrared spectroscopy (FT-IR). The technique of Differential Scanning Calorimetry (DSC) allowed the study of the crosslinking process of the different systems studied, allowing the determination of kinetic and thermodynamic parameters. The kinetic parameters of curing reaction systems of ME/AM and ME/AS were determined by methods Osawa, Kissinger and Barret. The thermal behavior of the products obtained was analyzed using thermogravimetric analysis (TGA). It was evident that the nature of anhydrides affects the thermodynamic and kinetics parameters of the crosslinking reaction. Values of DH for the reactions of epoxy ring opening are related to factors such as the steric size of the molecule and the position of the oxirane ring in the structure of the ME. The addition of BADGE in the mixture ME/anhydride increased molar mass and improves thermal and mechanical properties of polyester. By varying the composition of the system characteristics of the samples obtained were thermoplastic or crosslinked materials. The GPC results showed that the materials in the absence of BADGE are essentially oligomers. The rheology results indicated that all samples exhibit Newtonian fluid behavior. The viscosity values of the samples without BADGE indicated that these materials exhibited characteristics of highly viscous fluids and the samples in the presence of BADGE exhibited characteristics typical of solid. / Este trabalho investigou a reação de cura do ácido oleico epoxidado (ME) com forma estrela com diferentes anidridos, originando oligoésteres e poliésteres. O ácido oleico modificado foi obtido pela esterificação do ácido oleico com um aminoálcool dando origem ao aminoéster, seguido da epoxidação da dupla ligação. As reações de polimerização foram realizadas a partir da abertura dos anéis epóxi na presença de diferentes anidridos de ácido cíclico: anidrido ftálico (AF), anidrido maleico (AM) e anidrido succínico (AS). As estruturas dos produtos das reações foram elucidadas por Ressonância Magnética Nuclear (RMN) de 1H e 13C e Espectroscopia de Infravermelho (FT-IR). A técnica de Calorimetria Exploratória Diferencial (DSC) permitiu o estudo do processo de reticulação dos diferentes sistemas estudados, possibilitando a determinação de parâmetros cinéticos e termodinâmicos. Os parâmetros cinéticos da reação de cura dos sistemas ME/AM e ME/AS foram determinados pelos métodos Osawa, Kissinger e Barret. O comportamento térmico dos produtos obtidos foi estudado utilizando a técnica de DSC e Análise Termogravimétrica (TGA). Evidenciou-se que a natureza dos anidridos influencia nos parâmetros termodinâmicos e cinéticos da reação de reticulação. Os valores de DH para as reações de abertura do anel epóxi estão relacionados a fatores estéricos como o tamanho da molécula e a posição do anel oxirano na estrutura do ME. A adição de BADGE na mistura ME/anidrido aumentou a massa molar e melhorou as propriedades térmicas e mecânicas dos poliésteres. Variando a composição do sistema as características dos materiais obtidos passaram de termoplásticos a termorrígidos. Os resultados de GPC mostraram que os materiais sem BADGE consistem essencialmente de oligômeros e as resinas com BADGE se apresentaram insolúveis e com aspecto de resinas poliméricas sólidas. Os resultados de reologia indicaram que, todas as amostras apresentaram comportamento de fluido newtoniano. Os valores de viscosidade das amostras sem BADGE indicaram que estes materiais apresentaram características de fluidos altamente viscosos e as amostras na presença de BADGE apresentaram características típicas de sólido.

Made available in DSpace on 2014-06-11T19:35:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-25Bitstream added on 2014-06-13T20:25:59Z : No. of bitstreams: 1 dametto_pr_dr_araiq.pdf: 836476 bytes, checksum: 669c4cfbfa2c307d1a2e84db9dcfec19 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Foram sintetizados em solução aquosa os compostos [Ln(3-MeO-Bz)3].nH2O, sendo que Ln representa os lantanídeos trivalentes e Y(III) e 3-MeO-Bz representa o 3-metoxibenzoato. Os compostos foram sintetizados por adição estequiométrica do ligante nas respectivas soluções de cloretos ou nitratos de lantanídeos, sob agitação. A precipitação dos compostos foi instantânea e a caracterização foi realizada utilizando-se de métodos convencionais como: difratometria de raios X pelo método do pó, espectroscopia de absorção na região do infravermelho, análise elementar e as técnicas termoanalíticas TG/DTG (termogravimetria / termogravimetria derivada), TG – DTA (termogravimetria e análise térmica diferencial simultânea) e DSC (calorimetria exploratória diferencial). Estas técnicas forneceram informações sobre desidratação, modos de coordenação, comportamento térmico, composição e estrutura dos compostos sintetizados. Com os resultados das curvas TG e da complexometria, pôde-se estabelecer a fórmula geral de cada composto sintetizado. Pela análise dos difratogramas de raios X foi observado que todos os compostos sintetizados são cristalinos sem evidência de isomorfismo. A observação dos espectros na região do infravermelho sugeriram uma coordenação quelante-bidentada do ligante aos respectivos centros metálicos. As curvas TG - DTA e DSC forneceram informações inéditas e importantes sobre o comportamento e a decomposição térmica dos compostos sintetizados. / Solid state compounds of the type [Ln(3-MeO-Bz)3].nH2O, where Ln stands for trivalent La to Lu and Y(III) and 3-MeO-Bz is 3-methoxybenzoate, have been synthesized. The solid state compounds were prepared by stoichiometric addition slowly of the ligand solution to the respective metal chloride or nitrate solutions, with continuous stirring. The precipitation of the compounds was instantaneous and the characterization was performed using conventional methods such as: X-ray powder diffraction, infrared spectroscopy, elemental analysis, complexometry, simultaneous thermogravimetry and differential thermal analysis (TG-DTA), derivative thermogravimetry (DTG), differential scanning calorimetry (DSC). These techniques provided information about dehydration, coordination modes, thermal behavior, composition and structure of synthesized compounds. From TG curves and complexometry results, a general formula could be established for these compounds in the solid state. The X-ray powder patterns pointed out that the synthesized compounds have a crystalline structure without evidence concerning to the formation of isomorphous series. The infrared spectroscopy data suggest that 3- methoxybenzoate acts as a chelating bidentate ligand towards the metal ions considered in this work. The TG - DTA and DSC curves provided new and important information concerning the thermal behaviour and thermal decomposition of these compounds.

Made available in DSpace on 2014-12-17T14:57:46Z (GMT). No. of bitstreams: 1 LucianoACB.pdf: 490237 bytes, checksum: 162902433fcb2f6694977b9d544adc6e (MD5) Previous issue date: 2003-10-31 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / In the last decades there was a concentrate effort of researchers in the search for options to the problem of the continuity of city development and environmental preservation. The recycling and reuse of materials in industry have been considerate as the best option to sustainable development. One of the relevant aspects in this case refers to the rational use of electrical energy. At this point, the role of engineering is to conceive new processes and materials, with the objective of reducing energy consumption and maintaining, at the same time the benefits of the technology. In this context, the objective of the present research is to analyze quantitatively the thermal behavior of walls constructed with concrete blocks which composition aggregates the expanded polystyrene (EPS) reused in the shape of flakes and in the shape of a board, resulting in a &#8220;light concrete&#8221;. Experiments were conducted, systematically, with a wall (considerate as a standard) constructed with blocks of ordinary concrete; two walls constructed with blocks of light concrete, distinct by the proportion of EPS/sand; a wall of ceramic bricks (&#8220;eight holes&#8221; type) and a wall with ordinary blocks of cement, in a way to obtain a comparative analysis of the thermal behavior of the systems. Others tests conducted with the blocks were: stress analysis and thermal properties analysis (&#x3c1;, cp e k). Based on the results, it was possible to establish quantitative relationship between the concentration (density) of EPS in the constructive elements and the decreasing of the heat transfer rate, that also changes the others thermal properties of the material, as was proved. It was observed that the walls of light concrete presents better thermal behavior compared with the other two constructive systems world wide used. Based in the results of the investigation, there was shown the viability of the use of EPS as aggregate (raw material) in the composition of the concrete, with the objective of the fabrication of blocks to non-structural masonry that works as a thermal insulation in buildings. A direct consequence of this result is the possibility of reduction of the consume of the electrical energy used to climatization of buildings. Other aspect of the investigation that must be pointed was the reuse of the EPS as a raw material to civil construction, with a clear benefit to reducing of environmental problems / Nas ?ltimas d?cadas t?m sido grandes os esfor?os dos pesquisadores na busca por mais informa??es e conhecimentos sobre como se poder? continuar provendo o desenvolvimento das cidades sem que isso ocorra de forma agressiva ao meio ambiente. A reciclagem e o reaproveitamento de materiais que ainda possuem grande potencial de aplicabilidade s?o vistos como as solu??es mais evidentes em dire??o ao desenvolvimento sustent?vel. Um dos aspectos mais relevantes desse desenvolvimento refere-se ao uso racional da energia el?trica. E aqui se insere a Engenharia, com o papel de conceber t?cnicas e materiais inovadores cujo principal objetivo seja o de reduzir o consumo de energia el?trica, sem que obrigatoriamente se tenha que abrir m?o das comodidades conseguidas com sua aplica??o. Neste contexto, a presente pesquisa teve o objetivo de analisar de forma quantitativa o desempenho t?rmico de paredes constru?das com blocos de concreto cuja composi??o agrega o poliestireno expandido (EPS) reaproveitado na forma de flocos e em placas, constituindo desse modo um concreto leve. Realizaram-se experimentos, sistematicamente, com uma parede constru?da com blocos de concreto comum, considerada como refer?ncia; duas paredes com blocos de concreto leve, distintas pelas propor??es de EPS/areia; uma parede com tijolos cer?micos de oito furos e uma com blocos de cimento vazados, de forma a proceder-se com a analise comparativa dos desempenhos t?rmicos dos sistemas construtivos. Foram realizados ainda, ensaios de resist?ncia ? compress?o e ensaios de determina??o das propriedades termof?sicas (&#x3c1;, cp e k) dos blocos de concreto. Os resultados permitiram relacionar quantitativamente o efeito do EPS como agregado em elementos construtivos na redu??o da taxa de transfer?ncia de calor em fun??o da varia??o de densidade, que tamb?m interfere nas outras propriedades t?rmicas e mec?nicas do material, como comprovado. Constatou-se que as paredes de concreto leve apresentaram melhor desempenho t?rmico do que os outros dois sistemas construtivos consagrados comercialmente. P?de-se concluir que ? vi?vel empregar-se o EPS reaproveitado como material constituinte da mistura para concreto, com a finalidade de fabricar alvenaria de veda??o capaz de comportar-se tamb?m como isolante t?rmico entre o meio externo e o interno das edifica??es. Uma conseq??ncia direta disto ? a redu??o do consumo de energia el?trica utilizada pelos sistemas de climatiza??o, sem comprometer a situa??o de conforto t?rmico experimentada pelo usu?rio. Destaca-se ainda que o reaproveitamento do EPS como material de constru??o contribui com a redu??o dos problemas ambientais causados por este material. Al?m disso, os resultados obtidos neste estudo podem servir como refer?ncia aos projetistas na hora da escolha do material que ir? compor a alvenaria de veda??o, e assim poderem adequar os seus projetos ?s situa??es mais desej?veis

Nesta investigação aprofundou se no estudo do comportamento térmico das telhas Ibaplac, fabricada com embalagens pós consumo de Tetra Pak®, fazendo um estudo comparativo com outros sistemas construtivos de cobertura convencionais. O projeto enfoca o estudo térmico da cobertura, já que esta é uma parte da construção que recebe e absorve grande quantidade de energia pela radiação solar, influindo diretamente na temperatura interna da edificação podendo provocar temperaturas internas de desconforto. Isso que pode ocasionar prejuízo na saúde dos usuários, e também na economia, pela utilização aparelhos de condicionamento do ar interior para eliminar o desconforto térmico provocando maior consumo de energia. O estudo foi realizado por meio da instalação de equipamentos que coletam os dados de temperatura automaticamente. Foram monitorados diferentes espaços do interior de quatro células de teste e um protótipo de habitação popular ocupado. Foi selecionado um dia representativo das condições climáticas para análise, das temperaturas superficiais e do ar interior. Foram comparados os resultados das quatro células de teste (telha Ibaplac-forro madeira, telha Ibaplac-forro laje cerâmica, telha fibrocimento-forro laje cerâmica, telha cerâmica laje cerâmica), e do protótipo (telha Ibaplac-forro Ibaplac) para caracterizar o comportamento térmico num dia quente do sistema de cobertura em estudo. A análise dos dados obtidos com respeito ao comportamento térmico dos sistemas de cobertura em estudo foi realizada de acordo com a sua resposta térmica no dia representativo, determinada pela análise do período de medições. Também se utilizou das planilhas e gráficos elaborados a partir dos dados coletados pelo sistema automático de aquisição de dados datalogger CR10X e das imagens do satélite GOES obtidas na internet. No final foi feita a comparação do comportamento térmico dos diferentes sistemas de cobertura se levantando as conclusões finais, determinando assim o comportamento das telhas fabricadas com material reciclado Tetra Pak® em relação aos materiais convencionais estudados paralelamente. / In this research deepened the study of the thermal behavior of tiles Ibaplac, made with used packages of Tetra Pak®, making a comparative study with other conventional systems of roofs. The project mainly focuses on the thermal study cover, because this is a part of a building that receives and absorbs large amounts of energy by solar radiation, directly influencing the internal temperature of the building and this can cause internal temperatures of discomfort, which can even cause injury on the health of users, and also the economy, for the use of internal air-conditioning equipment in order to eliminate the thermal discomfort causing higher consumption of energy. The study was conducted by the installation of equipment that collects data from temperature automatically. They were monitored different areas of the interior of four experimental cells and a test prototype of popular house occupied. Was selected a representative day for the climate analysis, of the surface temperatures and internal air temperatures. The temperature results of the four test cells (Ibaplac tile-wood ceiling, Ibaplac tile-ceramic ceiling, asbestos tile-ceramic ceiling, ceramic tile-ceramic ceiling), and the prototype (Ibaplac tile-Ibaplac ceiling) was compared in order to determine the thermal behavior on heat of the roofs systems, compared an alternative roof system with an conventional roof systems, also analyzed in this research. .A data analysis of the thermal behavior of the roof systems under study was conducted in accordance with its thermal response in heat representative day, determined for examining period of measurements, in addition to the use of excel spreadsheets and graphics compiled from data collected by the automatically acquisition system of data \"datalogger CR10X\" and satellite GOES images obtained from the Internet. At the end were compared the thermal behavior results of the different roof systems in order to get the final conclusions, thereby determining the behavior of tiles made from recycled material Tetra Pak® in comparison with a conventional system of roofs studied parallel.

L’agro-composite de chanvre/amidon est un nouveau matériau 100% végétal constitué d'amidon et de chènevotte. C’est un matériau durable pour la construction et le bâtiment. L'objectif principal de cette thèse est d’innover, développer et optimiser cet agro-composite ainsi que ses propriétés mécaniques, acoustiques et thermiques. Dans ce travail, des essais expérimentaux sur le comportement mécanique, acoustique et thermique sont réalisées. Un liant particulier et innovant a été préliminairement testé et analysé afin de déterminer une composition optimale. Deux paramètres prépondérants de cette étude sont : le rapport chanvre/amidon (C/A) et la taille des particules de chènevotte. Différents mélanges de particules de chènevotte 0-20 mm, 0-15 mm et 0-5 mm sont donc étudiés en faisant varier le rapport de chènevotte/amidon (C/A) de 6, 8, 10, 12 à 14. La comparaison et l’analyse des résultats permet de mettre en lumière l’influence de chacun des paramètres sur les caractéristiques de notre agro-composite chanvre/amidon. Les agro-composites chanvre/amidon avec des mélanges de particules de chènevotte 0-5/0-15 mm et 0-5/0-20 mm, montrent qu’il existe une formulation qui permet d’obtenir un comportement mécanique optimal, un meilleur comportement acoustique et un excellent comportement thermique. / The hemp/starch agro-composite is a new material consisting of 100% vegetal starch and hemp shives. It is a durable material for building and construction. The aim of this thesis is to innovate, develop and optimize the agro-composites and those properties mechanical, acoustic and thermal behavior. In this work, experimental tests on the mechanical, thermal and acoustic behavior have been carried out. A particular and innovative binder has been preliminarily tested and analyzed in order to determine optimum composition. Both parameters studied are: hemp/starch (C/A) ratio and size of hemp shives. Various mixtures of hemp shives 0-20 mm or 0-15 mm with 0-5 mm were studied by varying the hemp/starch (C/A) ratio from 6, 8, 10, 12 to 14. The comparison and analysis of results allows making the obvious influence of each parameter on the characteristics of our hemp/starch agro-composite. The hemp/starch agro-composite with mixtures hemp shives 0-5/0-15 mm and 0-5/0-20 mm, show that there is a formulation that achieves optimum mechanical behavior, better acoustic behavior and excellent thermal behavior.

La pyrolyse douce est un procédé prometteur et largement utilisé, mené à une température de 200 à 300 °C dans une atmosphère inerte afin de produire des matériaux durables (bois traité thermiquement) ou des combustibles solides (bois torréfié). Le but de cette étude est d’étudier les bois traités thermiquement dans un réacteur à l’échelle semi-industrielle pour une production durable de matériaux. Deux essences de bois européennes différentes, une essence de feuillus (peuplier, Populus nigra) et une essence de résineux (sapin, Abies pectinata), sont utilisées pour réaliser les expériences. La présente recherche est divisée en trois parties. Dans la première partie, le comportement thermique des planches de bois est étudié dans un réacteur à l’échelle semi-industrielle. Les expériences sont effectuées à 200-230 °C avec une vitesse de chauffe de 0.2 °C min-1 dans un environnement sous vide (200 hPa) pour intensifier la dégradation thermique. Quatre étapes différentes de dégradation thermique lors du traitement thermique du bois sont définies, en fonction de l'intensité de la perte de masse différentielle (DML). Les caractéristiques de dévolatilisation du bois traité sont évaluées à l'aide de l'indice de dévolatilisation (ID) basé sur les résultats de l'analyse immédiate. La corrélation de l'ID par rapport à la perte de masse des deux essences de bois est fortement caractérisée par une distribution linéaire, ce qui permet de fournir un outil simple et utile pour prédire la perte de masse du bois. Dans la seconde partie de l’étude, plusieurs analyses (spectroscopie infrarouge à transformée de Fourier, diffraction des rayons X, mesure du changement de couleur, teneur en humidité à l’équilibre et angle de contact) ont été réalisées. Les résultats obtenus démontrent clairement la dégradation thermique lors des réactions de déshydratation, de désacétylation, de dépolymérisation et de condensation au cours du traitement thermique. Les phénomènes de changement de couleur et de transformation hygroscopique observés sont illustrés et discutés en détail. La décarbonisation (DC), la déshydrogénation (DH) et la désoxygénation (DO) des bois traités sont également évaluées. Il s'avère que les trois indices peuvent être bien corrélés à la variation de couleur totale et à l'étendue de la réduction de l'hygroscopicité (HRE). Dans la dernière partie de l'étude, une modélisation cinétique du traitement thermique du bois est développée sur la base d’un schéma cinétique en deux étapes. La cinétique obtenue permet de prédire avec succès le rendement en solide de planches de bois lors du traitement dans un réacteur à l’échelle semi-industrielle. Dans le même temps, une prévision de la composition élémentaire est proposée. Celle-ci est basée sur les analyses élémentaires (ultimes) du bois non traité et du bois traité, ainsi que sur les rendements instantanés en solides. Les résultats indiquent que la prédiction des profils C, H et O est en bon accord avec les changements de composition attendus dans le matériau au cours du traitement. En résumé, les résultats obtenus et la cinétique établie sont propices à l’identification des mécanismes de dégradation thermique du bois et peuvent être utilisés pour le traitement thermique et la conception de réacteurs dans l'industrie afin de produire des matériaux bois adaptés à diverses applications. / Mild pyrolysis is a promising and widely applied process conducted at 200-300 °C in an inert condition to produce sustainable materials (i.e. heat treated wood) or solid fuel (i.e. torrefied wood). The aim of this study is to investigate the woods heat treated in a semi-industrial scale reactor for sustainable material production. Two different European wood species, a hardwood species (poplar, Populus nigra) and a softwood species (fir, Abies pectinata), are used to perform the experiments. The present research is divided into three parts. In the first part, the thermal behavior of wood boards is studied in a semi-industrial scale reactor. The experiments are carried out at 200-230 °C with a heating rate of 0.2 °C min-1 in a vacuum condition (200 hPa) to intensify the thermal degradation. Four different stages of thermal degradation during wood heat treatment are defined based on the intensity of differential mass loss (DML). The devolatilization characteristics of treated woods are evaluated by the devolatilization index (DI) based on the results of proximate analysis. The correlation of DI with respect to mass loss of the two wood species is strongly characterized by linear distribution, which is able to provide a simple tool to predict the mass loss of wood. In the second part of the study, a number of analyses, such as Fourier-transform infrared spectroscopy, X-ray diffraction, measurement of color change, equilibrium moisture content, and contact angle) are performed to evaluate the property changes of treated woods. The obtained results clearly demonstrate the thermal degradation through dehydration, deacetylation, depolymerization, and condensation reactions during the heat treatment. The observed phenomena of color change and hygroscopic transformation are illustrated and discussed in detail. The decarbonization, dehydrogenation, and deoxygenation of the treated woods are also evaluated. It is found that the three indexes can be well correlated to the total color difference and hygroscopicity reduction extent (HRE). In the last part of the study, the kinetic modeling of wood heat treatment is developed based on a two-step kinetic scheme. The obtained kinetics successfully predict dynamic solid yield of wood boards during the treatment in the semi-industrial reactor. Meanwhile, the prediction of elemental composition is also performed by a direct method based on the elemental analyses of untreated and treated woods at the end of the treatment, as well as the instantaneous solid yield. The results point out that the prediction of C, H, and O profiles are in good agreement with expected composition changes in the wood materials during treatment. In summary, the obtained results and established kinetics are conducive to recognizing the mechanisms of wood thermal degradation and can be used for heat treatment process and reactor design in industry to produce wood materials for various applications.