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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Identification and quantification of lipid metabolites in cotton fibers: Reconciliation with metabolic pathway predictions from DNA databases.

Wanjie, Sylvia W. 05 1900 (has links)
The lipid composition of cotton (Gossypium hirsutum, L) fibers was determined. Fatty acid profiles revealed that linolenate and palmitate were the most abundant fatty acids present in fiber cells. Phosphatidylcholine was the predominant lipid class in fiber cells, while phosphatidylethanolamine, phosphatidylinositol and digalactosyldiacylglycerol were also prevalent. An unusually high amount of phosphatidic acid was observed in frozen cotton fibers. Phospholipase D activity assays revealed that this enzyme readily hydrolyzed radioactive phosphatidylcholine into phosphatidic acid. A profile of expressed sequence tags (ESTs) for genes involved in lipid metabolism in cotton fibers was also obtained. This EST profile along with our lipid metabolite data was used to predict lipid metabolic pathways in cotton fiber cells.
2

Application of X-ray Diffraction Methods and Molecular Mechanics Simulations to Structure Determination and Cotton Fiber Analysis

Moore, Zakhia 19 December 2008 (has links)
The results of three very different studies are presented. X-ray diffraction has been utilized for single-crystal structure determinations, fiber diffraction analyses, and in conjunction with molecular modeling of Cellulose IIII. Although each technique is different in its sampling, data acquisition, data treatment, and identification, the common denominator has been the use of x-rays. The single-crystal structure determination of ethylene glycol bis(tropane-3-carboxylate) is presented as an example of the use of modern single-crystal x-ray instrumentation including the use of coupled charged devices (CCDs) as detectors for accurate data collection and rapid elucidation of crystal structures. The structure determination of Cellulose IIII by x-ray diffraction and computer modeling is presented to show how the use of x-rays in weakly diffracting materials can generate a reliable structure and be a key component in model building. Finally, a study is presented in which x-ray fiber diffraction data is utilized to investigate possible correlations between the crystallite orientation, crystallinity, crystallize size and the strength properties of cotton fibers collected from various countries.
3

Diallel analysis and heritability estimates of fiber traits for ELS, Gossypium hirsutum L., progeny.

Berger, Gregory L. 16 January 2010 (has links)
With a demand for high-quality cotton fiber in international markets, improvement of fiber quality in U.S. grown commercial cultivars is necessary. Smith, Hague, Thaxton, and Jones developed a group of experimental lines in 2008 that produced extra-long staple fiber (>35.6 mm). This study determined general combining ability (GCA), and specific combining ability (SCA) of four experimental ELS lines and four commercial cultivars utilizing biplot and conventional diallel analysis, determined performance of F2 progeny, calculated broad-sense (H2) heritability estimates for F2 progeny, and verified the ability of selected parental combinations to produce variable segregating populations with variability of fiber traits. Initial crosses were made in 2007, with additional crosses being made in the field and in a greenhouse in 2008. F1 progeny and parents were grown in a replicated trial near College Station, TX, in 2007 and 2008. F2 progeny lines and parents were grown in replicated trials at two locations in 2008. Due to a significant GxY interaction for all F1 fiber traits, data were reported by years. Experimental ELS lines showed positive GCA effects for fiber length, strength, and length uniformity, while the majority of commercial lines showed negative effects. These findings suggest experimental ELS lines contain alleles for fiber length and strength not present in this particular set of commercial cultivars. Experimental ELS lines exhibited negative GCA effects for lint percent, which suggests further selection is needed for these lines to be commercially competitive. Performances of F2 lines suggest differences in fiber traits are predominantly due to additive gene action. Furthermore, data suggests alleles for fiber length and strength is present in the experimental ELS lines not present in the commercial cultivars. F2 progeny exhibited moderate heritability for all fiber traits. Sufficient variability exists within selected F2 progeny to select for phenotypes exhibiting improved fiber quality over commercial cultivar potential with similar agronomic qualities of commercial cultivars. The ELS lines are a useful source of germplasm for plant breeders looking to improve fiber qualities in their programs.
4

Estudo interdisciplinar entre reciclagem têxtil e o design: avaliação de compósitos produzidos com fibras de algodão / Interdisciplinary study between textile recycling and design: evaluation of composites produced with cotton fibers

Zonatti, Welton Fernando 10 January 2013 (has links)
Visando o gerenciamento dos artigos têxteis advindos do descarte doméstico e dos refugos gerados nos processos de fabricação, a reciclagem e a reutilização surge como uma resposta emergencial aos problemas ambientais do setor de têxtil e moda. O presente estudo teve como principais objetivos realizar uma revisão bibliográfica sobre técnicas de reuso e reciclagem de têxteis, principalmente das fibras de algodão, bem como temas relacionados à ecologia industrial, ao design de moda e ao eco design. Na sua parte experimental também visou realizar ensaios de microscopia e de determinação de regain da fibra de algodão, bem como ensaios de tração, alongamento e microscopia em compósitos produzidos com três diferentes tipos de resinas termorrígidas (epóxi, poliéster ortoftálico e poliuretano) reforçadas com fibras têxteis de algodão, sugestão possível para a diminuição dos refugos têxteis em aterros sanitários. Para tais compósitos foram apontadas aplicações no setor de moda. Conclui-se que os compósitos produzidos a partir de resíduos têxteis poderiam trazer benefícios ao meio-ambiente, pois além de possuírem atribuições como resistência e coesão, podem ser destinados à área de moda, entre outras áreas, pelos atributos visuais que proporcionam. Assim, são capazes de suprir necessidades específicas de consumo do mercado, ávido por novidades, bem como de suprir a demanda por estudos de novos materiais no setor de têxtil e moda, que carece de bibliografia especifica que reúna uma análise técnica e estética abrangendo todas as fases produtivas de materiais, processos, criação e design. / Aiming management of textiles coming from household waste and scrap generated in the manufacturing processes, recycling and reuse arise as emergency responses to the environmental problems of the textile and fashion industry. The present study main objectives were to perform an interdisciplinary literature review focused on techniques of reuse and recycling of textiles, mainly cotton fibers, as well as topics related to industrial ecology, the fashion design and eco design. On experimental part it also aimed to carry out tests of microscopy and regain determination of cotton fibers as well as microscopy, tensile and elongation tests in composites made with three different types of thermoset resins (epoxy, polyester orthophthalic and polyurethane) reinforced with textile cotton fibers, configuring possible suggestion for the reduction of textile waste in landfills. For applications such composites were pointed in the fashion sector. It is possible to conclude that the composites made from textile waste could bring benefits to the environment, because besides possessing strength and cohesion functions, they could be assigned to fashion design field from the visual attributes they provide. Thus, they are able to supply specific needs of the consumer market, eager for news, and to furnish the demand for studies of new materials in the textile and fashion sectors, which lacks specific bibliography that bring together aesthetic and technical analysis covering all production phases of materials, processes, creation and design.
5

Estudo interdisciplinar entre reciclagem têxtil e o design: avaliação de compósitos produzidos com fibras de algodão / Interdisciplinary study between textile recycling and design: evaluation of composites produced with cotton fibers

Welton Fernando Zonatti 10 January 2013 (has links)
Visando o gerenciamento dos artigos têxteis advindos do descarte doméstico e dos refugos gerados nos processos de fabricação, a reciclagem e a reutilização surge como uma resposta emergencial aos problemas ambientais do setor de têxtil e moda. O presente estudo teve como principais objetivos realizar uma revisão bibliográfica sobre técnicas de reuso e reciclagem de têxteis, principalmente das fibras de algodão, bem como temas relacionados à ecologia industrial, ao design de moda e ao eco design. Na sua parte experimental também visou realizar ensaios de microscopia e de determinação de regain da fibra de algodão, bem como ensaios de tração, alongamento e microscopia em compósitos produzidos com três diferentes tipos de resinas termorrígidas (epóxi, poliéster ortoftálico e poliuretano) reforçadas com fibras têxteis de algodão, sugestão possível para a diminuição dos refugos têxteis em aterros sanitários. Para tais compósitos foram apontadas aplicações no setor de moda. Conclui-se que os compósitos produzidos a partir de resíduos têxteis poderiam trazer benefícios ao meio-ambiente, pois além de possuírem atribuições como resistência e coesão, podem ser destinados à área de moda, entre outras áreas, pelos atributos visuais que proporcionam. Assim, são capazes de suprir necessidades específicas de consumo do mercado, ávido por novidades, bem como de suprir a demanda por estudos de novos materiais no setor de têxtil e moda, que carece de bibliografia especifica que reúna uma análise técnica e estética abrangendo todas as fases produtivas de materiais, processos, criação e design. / Aiming management of textiles coming from household waste and scrap generated in the manufacturing processes, recycling and reuse arise as emergency responses to the environmental problems of the textile and fashion industry. The present study main objectives were to perform an interdisciplinary literature review focused on techniques of reuse and recycling of textiles, mainly cotton fibers, as well as topics related to industrial ecology, the fashion design and eco design. On experimental part it also aimed to carry out tests of microscopy and regain determination of cotton fibers as well as microscopy, tensile and elongation tests in composites made with three different types of thermoset resins (epoxy, polyester orthophthalic and polyurethane) reinforced with textile cotton fibers, configuring possible suggestion for the reduction of textile waste in landfills. For applications such composites were pointed in the fashion sector. It is possible to conclude that the composites made from textile waste could bring benefits to the environment, because besides possessing strength and cohesion functions, they could be assigned to fashion design field from the visual attributes they provide. Thus, they are able to supply specific needs of the consumer market, eager for news, and to furnish the demand for studies of new materials in the textile and fashion sectors, which lacks specific bibliography that bring together aesthetic and technical analysis covering all production phases of materials, processes, creation and design.
6

Desenvolvimento e avaliação de um descaroçador móvel e prensa enfardadeira para o beneficiamento do algodão. / Development and evaluation of a mobile gin and baler for cotton processing.

JERÔNIMO, Jeane Ferreira. 14 June 2018 (has links)
Submitted by Deyse Queiroz (deysequeirozz@hotmail.com) on 2018-06-14T14:48:30Z No. of bitstreams: 1 JEANE FERREIRA JERÔNIMO - TESE PPGEA 2012..pdf: 42693746 bytes, checksum: c91e8aa096fd962343ca9b15139df5dd (MD5) / Made available in DSpace on 2018-06-14T14:48:30Z (GMT). No. of bitstreams: 1 JEANE FERREIRA JERÔNIMO - TESE PPGEA 2012..pdf: 42693746 bytes, checksum: c91e8aa096fd962343ca9b15139df5dd (MD5) Previous issue date: 2012-02 / Na busca de melhorias nos atuais níveis de produtividade e na redução nos custos de produção do algodoeiro no Brasil, novas tecnologias vêm sendo incorporadas ao sistema de produção, visando oferecer alternativa de verticalização da produção através do seu beneficiamento, com equipamentos compactos e itinerantes, possibilitando entre os produtores ou associações a agregação de valor à sua produção. Nesta linha de investigação objetivou-se com o presente trabalho desenvolver um conjunto composto por descaroçador, prensa enfardadeira e reboque, que atenda aos cotonicultores da agricultura familiar. O descaroçador compõe-se de: limpador com alimentação manual, cilindro de serras, cilindro de escovas, condensador e rolo; a prensa enfardadeira: chapa (masseira), cilindros hidráulicos, bomba hidráulica, válvula de controle de acionamento, dispositivos de filtragem do óleo hidráulico e manómetro; e o reboque: chassi de cantoneiras em U quatro rodas de aro 13, pontas de eixo, dois feixes de cinco molas, lastro em chapa de ferro e freio próprio. O conjunto desenvolvido foi avaliado e validado em laboratório e em campo por cotonicultores de associações ligados à agricultura familiar considerando as principais características: tecnologias da fibra e as físicas e fisiológicas da semente. Para o descaroçador estudou-se rotações, cultivares, tipos de serras e processos de limpeza; para a prensa enfardadeira foi avaliado o número de prensagem e sua capacidade para formação de um fardo; enquanto para o reboque foi considerado o coeficiente de segurança do dimensionamento do eixo e do chassi. Com base nos resultados, o conjunto descaroçador, prensa enfardadeira e reboque atendeu plenamente com a eficiência requerida pela indústria têxtil, os objetivos propostos comprovaram que as características tecnológicas da fibra do algodão beneficiado se mantiveram dentro dos padrões estabelecidos pelas normas de classificação da indústria têxtil por não danificar a qualidade das sementes; na avaliação e validação do conjunto pelos agricultores composto de 15 itens, em que se considera rendimento do descaroçador, o peso do fardo recebeu o conceito "muito bom" dos cotonicultores da agricultura familiar. / In the search of improvements in current yield rates and simultaneous costs reduction for cotton production in Brazil, new Technologies have been incorporated into the production system, to offer an alternative to vertical integration of production through their processing, with compact and mobile ginning equipment, allowing producers and associations add value to their production. In this way of research, the present work aimed to develop a machine composed by gin, press baler and tow, which concerns the familiar cotton growers. The gin machine consists of a manual feeder cleaner, saws cylinder, brushes cylinder, condenser and coil. The baler press consists of veneer, hydraulic cylinders, hydraulic pump, control valve actuation, filtering devices for hydraulic oil and manometer: and the tow composed by chassis of U corner, 13" wheels, axis cusp, two bundles with five coil springs, iron ballast and self brake. The hole set has been evaluated and validated in field and by cotton growers of family farming associations considering the main characteristics of: fiber technology and physical and physiological of seed. For the ginning was studied the rotations, cultivars, saws types and cleaning processes; for the baler press was evaluated the number of presses and the capacity for forming a bale; while to the tow was considerate the safety factor of the axis and chassis scaling. Based on the results, the set of gin, baler and tow fully complied with the efficiency required by textile industry. The proposed goals proved that the technological characteristics of the cotton fiber benefited remained within the standards established by classification norm for the textile industry to not damage the quality of seeds. During the evaluation and validation made by farmers, composed by 15 items, considering efficiency of gin and the bale weight, this machine received the concept "very good" of the family cotton growers.
7

Multivariate Statistical Methods Applied to the Analysis of Trace Evidence

Szkudlarek, Cheryl Ann 22 August 2013 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / The aim of this study was to use multivariate statistical techniques to: (1) determine the reproducibility of fiber evidence analyzed by MSP, (2) determine whether XRF is an appropriate technique for forensic tape analysis, and (3) determine if DART/MS is an appropriate technique for forensic tape analysis. This was achieved by employing several multivariate statistical techniques including agglomerative hierarchical clustering, principal component analysis, discriminant analysis, and analysis of variance. First, twelve dyed textile fibers were analyzed by UV-Visible MSP. This analysis included an inter-laboratory study, external validations, differing preprocessing techniques, and color coordinates. The inter-laboratory study showed no statistically significant difference between the different instruments. The external validations had overall acceptable results. Using first derivatives as a preprocessing technique and color coordinates to define color did not result in any additional information. Next, the tape backings of thirty-three brands were analyzed by XRF. After chemometric analysis it was concluded that the 3M tapes with black adhesive can be classified by brand except for Super 33+ (Cold Weather) and Super 88. The colorless adhesive tapes were separated into two large groups which were correlated with the presence of aluminosilicate filler. Overall, no additional discrimination was seen by using XRF compared to the traditional instrumentation for tape analysis previously published. Lastly, the backings of eighty-nine brands of tape were analyzed by DART/MS. The analysis of the black adhesive tapes showed that again discrimination between brands is possible except for Super 33+ and Super 88. However, now Tartan and Temflex have become indistinguishable. The colorless adhesive tapes again were more or less indistinguishable from one another with the exception of Tuff Hand Tool, Qualpack, and a roll of 3M Tartan, which were found to be unique. It cannot be determined if additional discrimination was achieved with DART/MS because the multivariate statistical techniques have not been applied to the other instrumental techniques used during tape analysis.

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