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Caracteriza??o acessos de sisal usando descritores da planta e da fibraCarneiro, Jan?ira Lopes dos Santos 21 March 2016 (has links)
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Tese Janaira - ULTIMA_VERS?O_TESE 11_12.pdf: 2389329 bytes, checksum: 317a53e7aedac40bb5150d1d444bfee3 (MD5) / Made available in DSpace on 2018-01-26T22:34:50Z (GMT). No. of bitstreams: 1
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Previous issue date: 2016-03-21 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Agave sisalana Perr., belongs to the Agavaceae family, and has a center of plant diversity in Mexico. In Brazil, the first seedlings were introduced in the Northeast, specifically in Bahia, in 1903. Sisal is a species known for its production of lignocellulosic fibers. The by-product, result of the defibration of sisal leaves, is an alternative source for biogas procdution, pharmaceutical input and as composite used in civil construction. In the leaf juice a high pharmacological potential such as inulin and hecogenin was quantified - precursor in the synthesis of corticosteroids. Some studies regarding sisal fibers and their input with pharmacological potential are described in the literature, however studies on the characterization of A. sisalana, in particular regards to morphological, biochemical and physical plant in nature is incipient. Therefore, the present work attempt to identify new applications for sisal by pre-breeding studies by morphological analysis of the plants and to study the morphology of their fibers, analyzing their microstructures, as well as mechanical fiber studies. Morphological analyzes showed that there is variability and heterogeneity among populations, and small plants has higher sugar content and maximum mechanical resistance of the fibers. Mechanical properties studied indicate that fibers vary within and among genotypes of different areas. Morphological and microstructural analyzes of fibers showed that evaluated areas, as well as the distinct regions of apex and base of fibers, have small differences in micro structural characteristics and that different edaphoclimatic conditions do not interfere in the chemical constitution, but intervene in the amount of organic compounds among individuals. / A Agave sisalana Perr., pertence ? fam?lia Agavaceae, e possui centro de diversidade o M?xico. No Brasil, as primeiras mudas foram introduzidas na Regi?o Nordeste, especificamente na Bahia, em 1903. O sisal ? uma esp?cie conhecida por sua produ??o de fibras lignocelul?sicas. O subproduto, resultado do desfibramento das folhas de sisal, ? uma fonte alternativa para a gera??o do biog?s, insumo farmac?utico e como comp?sito utilizado na constru??o civil. No suco das folhas foi quantificado um alto potencial farmacol?gico como a inulina e a hecogenina - precursor na s?ntese de corticoester?ides. Alguns estudos referentes ?s fibras de sisal e seu insumo com potencial farmacol?gico s?o descritos na literatura, entretanto estudos sobre a caracteriza??o da esp?cie A. sisalana, e em particular no que diz respeito as an?lises morfol?gicas, bioqu?micas e f?sicas da planta in natura s?o incipientes. Portanto, o presente trabalho procurou identificar novas aplica??es para o sisal, por meio de estudos de pr?-melhoramento atrav?s de an?lises morfol?gicas das plantas e, efetuar estudos da morfologia de suas fibras, analisando suas microestruturas, assim como realizar estudos mec?nicos da fibra. As an?lises morfol?gicas mostraram que existe variabilidade e heterogeneidade entre as popula??es avaliadas, e que plantas de baixa estatura possuem maior teor em a??cares e m?xima resist?ncia mec?nica das fibras. As propriedades mec?nicas estudadas indicaram que as fibras sofrem varia??o dentro e entre os gen?tipos de diferentes ?reas. As an?lises morfol?gicas e micro estrutural das fibras demonstraram que as ?reas avaliadas, assim como as distintas regi?es de ?pice e base das fibras, possuem pequenas diferen?as quanto ?s caracter?sticas micro estruturais e que distintas condi??es edafoclim?ticas n?o interferem na constitui??o qu?mica, mas interv?m na quantidade dos compostos org?nicos entre os indiv?duos.
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Caracteriza??o e an?lise das propriedades da fibra de Macambira (Bromelia Laciniosa)Pimentel, Juliana Rangel de Morais 27 September 2012 (has links)
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Previous issue date: 2012-09-27 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Concern for the environment and the exploitation of natural resources has motivated the development of research in lignocellulosic materials, mainly from plant fibers. The major attraction of these materials include the fact that the fibers are biodegradable, they are a renewable natural resource, low cost and they usually produce less wear on equipment manufacturing when compared with synthetic fibers. Its applications are focused on the areas of technology, including automotive, aerospace, marine, civil, among others, due to the advantageous use in economic and ecological terms. Therefore, this study aims to characterize and analyze the properties of plant fiber macambira (bromelia laciniosa), which were obtained in the municipality of Ielmo Marino, in the state of Rio Grande do Norte, located in the region of the Wasteland Potiguar. The characterization of the fiber is given by SEM analysis, tensile test, TG, FTIR, chemical analysis, in addition to obtaining his title and density. The results showed that the extraction of the fibers, only 0.5% of the material is converted into fibers. The results for title and density were satisfactory when compared with other fibers of the same nature. Its structure is composed of microfibrils and its surface is roughened. The cross section has a non-uniform geometry, therefore, it is understood that its diameter is variable along the entire fiber. Values for tensile strength were lower than those of sisal fibers and curau?. The degradation temperature remained equivalent to the degradation temperatures of other vegetable fibers. In FTIR analysis showed that the heat treatment may be an alternative to making the fiber hydrophobic, since, at high temperature can remove the hemicellulose layer, responsible for moisture absorption. Its chemical constitution is endowed with elements of polar nature, so their moisture is around 8.5% which is equivalent to the percentage of moisture content of hydrophilic fibers. It can be concluded that the fiber macambira stands as an alternative materials from renewable sources and depending on the actual application and purpose, it may achieve satisfactory results / A preocupa??o com o meio ambiente e com o aproveitamento de recursos naturais tem motivado o desenvolvimento de pesquisas na ?rea de materiais lignocelul?sicos, principalmente de fibras vegetais. Os grandes atrativos desses materiais incluem o fato das fibras serem biodegrad?veis, serem um recurso natural renov?vel, terem geralmente baixo custo e produzirem menor desgaste nos equipamentos de fabrica??o quando comparadas com as fibras sint?ticas. Suas aplica??es est?o voltadas para a ?rea tecnol?gica, incluindo ind?strias automotiva, aeroespacial, naval, civil entre outras, devido ao uso vantajoso em termos econ?micos e ecol?gicos. Portanto, o presente trabalho tem como objetivo caracterizar e analisar as propriedades da fibra vegetal macambira (bromelia laciniosa), cuja foram obtidas no munic?pio de Ielmo Marinho, no estado do Rio Grande do Norte, situado na regi?o do Agreste Potiguar. A caracteriza??o da fibra se deu pelas an?lises de Microscopia Eletr?nica de Varredura (MEV), ensaio de tra??o, Termogravimetria (TG), Espectroscopia no Infravermelho por Transformada de Fourier (FTIR), an?lise qu?mica, al?m da obten??o de sua densidade linear. Os resultados mostraram que na extra??o das fibras, apenas 0,5% do material ? convertido em fibras. Os resultados para densidade foram satisfat?rios quando comparados com outras fibras de mesma natureza. Sua estrutura ? constitu?da por microfibrilas e sua superf?cie ? rugosa. A se??o transversal n?o apresenta uma geometria uniforme, portanto, entende-se que seu di?metro ? vari?vel ao longo de toda fibra. Os valores para resist?ncia a tra??o foram inferiores aos de outras fibras lignocelul?sicas. A temperatura de degrada??o permaneceu equivalente ?s temperaturas de degrada??o das demais fibras vegetais. Na an?lise de FTIR, mostrou-se que o tratamento t?rmico pode provocar um rompimento das mol?culas. O percentual Regain confirmou-se em 8,5%. Pode-se concluir que a fibra de macambira destaca-se como mais uma alternativa dentre os materiais de fontes renov?veis e dependendo da sua real aplica??o e finalidade, a mesma pode alcan?ar resultados satisfat?rios
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