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Bomullens nya ansikte : Kan man finna ett material som kan agera substitut till bomullen för producenter inom yrkeskläder? / Cotton’s new face : Is there a material, which can be a substitute to cotton for work wear producers?Wilen, Linda, Norin, Daniel, Eriksson, Anna January 2011 (has links)
Syftet med undersökningen är att undersöka, beskriva och analysera kring hur vida det finns ett bra substitut till bomull. Undersökningen kommer att belysa hur marknaden ser ut i dag och vilka material som används. Vidare utreds parametrarna funktion, kundnytta och hållbarhet, som kan komma att spela roll i valet av material för producenter av yrkeskläder. I dagsläget finns det inget solklart val av material som skulle kunna mäta sig med bomullen gällande de parametrarna som uppsatsen tar upp. Vad man väljer att använda istället för bomull beror mycket på hur företagen väljer att fokusera gällande just funktion, kundnytta och hållbarhet. Faktorer så som ledtider och prisaspekter spelar också roll, men dessa har uppsatsen valt att förbise. Det handlar om att ha tillräckligt starka argument som väger över bomullens fördelar. Där kan man exempelvis trycka på miljöfrågor gällande nykommande material. Om man bara ska se till att hitta ett bättre alternativ hållbarhetsmässigt än bomull så finns det många alternativ att välja mellan.The purpose of the study is to explore, describe and analyze on how there is a good substitute for cotton. The study will illustrate how the market stands today and what materials that are being used. Further investigation of the various parameters of operation, customer value and durability, which may play a role in the selection of materials for the manufacturers in work wear.Today, there is no obvious choice of materials that could compete with cotton with the current parameters which the essay addresses. What companies choose to use instead of cotton depends on how they choose to focus on function, customer value and durability. Factors such as lead times and price aspects also play an important role, but these are excluded in the essay. It all comes down to having strong arguments that weigh more than the benefits of cotton. For example, pressing environmental issues concerning newcomer materials. If you only want to find a better alternative in terms of durability than cotton, there are many options to choose from. / Program: Textil produktutveckling med entreprenörs- och affärsinriktning
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Study of agro-composite hemp/polypropylene : treatment of fibers, morphological and mechanical characterization / Étude des agro-composites chanvre/polypropylène : traitement des fibres, caractérisation morphologique et mécaniqueHan, Hongchang 04 February 2015 (has links)
L’utilisation des fibres végétales dans les polymères composites suscite de nombreuses investigations. Avant de mélanger les fibres végétales dans le polymère, un traitement chimique peut être effectué permettant de réduire l’hydrophilicité des fibres et d’améliorer l'adhérence à l’interface fibre/matrice. Dans cette thèse, l'eau et l'alcali sont utilisés d'abord pour traiter les fibres de chanvre, puis trois agents silane : 3-(triméthoxysilyl)propyl méthacrylate (MPS), N-[3- (triméthoxysilyl)propyl] aniline (PAPS) et (3-Aminopropyl)-triéthoxysilane (APS), sont utilisés pour modifier plus ou moins la surface des fibres de chanvre. Ces fibres traitées ou modifiées sont ensuite mélangées avec le polypropylène (PP) pour la fabrication des composites. Les effets de ces différents traitements sur la structure, les composants et l’hydrophilicité des fibres, et les propriétés mécaniques de ces composites sont mis en évidence. Nous avons étudié ensuite l’effet de vieillissement sur leurs comportements mécaniques, notamment l'humidité, la température et le rayonnement ultraviolet. Les résultats ont montré que le traitement de fibres par l'eau et l’alcali a des effets considérables sur la structure de fibres, les propriétés mécaniques et la durabilité des composites renforcés. La modification par l'agent de silane a une influence moins importante sur la structure des fibres, pourtant son groupe fonctionnel a une influence significative sur les propriétés mécaniques et la résistance au vieillissement des composites renforcés / Using agro fiber as reinforcement of polymer com-posites attracts numerous investigations due to the good mechanical properties and environmental benefits. Prior to blend agro fiber with polymer, chemical treatment can be employed to treat agro fiber for the purpose of reducing the hydrophilicity of fiber and improving the interfacial adhesion fi-ber/polymer matrix. In this thesis, water and alkali are utilized to treat hemp fiber firstly and then three silane agent as 3-(Trimethoxysilyl)propyl methacry-late (MPS), N-[3-(Trimethoxysilyl)propyl]aniline (PAPS) and (3-Aminopropyl)-triethoxysilane (APS) are employed to modify the hemp fiber surface. These treated or modified fibers are blended respectively with polypropylene (PP) to fabricate the hemp fiber/PP composites. The effects of these different treatments on the structure, components and hydro-philicity of fiber, and the mechanical properties of the reinforced PP composites are studied. Moreover, the accelerated ageing experiments including humidity, temperature and ultraviolet of the reinforced PP composites are conducted. The results showed that the fiber treatment of water and alkali has a considerable effect on fiber structure, mechanical properties and durability of the reinforced compo-sites. The silane agent modification of fiber has less influence on the fiber structure but its functional group has great influence on the mechanical proper-ties and ageing resistance of the reinforced compo-sites.
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Manufacturing of hemp/PP composites and study of its residual stress and aging behavior / Elaboration des chanvre/PP composites et étude des contraintes résiduelles et du comportement de vieillissementsZhang, Xiaohui 31 May 2016 (has links)
Depuis quelques années les matériaux composites à base de fibres naturelles sont de plus en plus utilisés pour les nouvelles performances qu’ils proposent. C’est surtout au niveau des fibres naturelles que de nouvelles propriétés sont proposées. Dans ce travail, nous nous sommes essentiellement intéressés aux fibres naturelles de chanvre. Ces fibres sont déjà fortement utilisées dans l’automobile et la construction. En Europe, ces fibres sont produites principalement en France et plus particulièrement dans l’Aube. Pour développer des agro-composites hautes performances, c’est sous la forme de fibres longues et de tissus que nous avons choisi d’orienter ce travail de thèse. Nous avons choisi la thermocompression pour élaborer des plaques avec des tissus de chanvre et une matrice en polypropylène (PP). Ce travail permet de voir l’influence des conditions d’élaboration sur le comportement mécaniques de ces agro-composites. Cette thèse permet aussi de voir l’effet du vieillissement aux UV et à l’Humidité sur les performances de ces matériaux. Enfin une analyse des contraintes résiduelles par la méthode du trou incrémental permet de voir leurs effets sur ces agro-matériaux / In recent years composite materials based on natural fibers are more and more used for their new performances. Natural fibers propose attractive environmental, mechanical and thermal properties.In this work, we are firstly interested in hemp fibers. These fibers are already used in the automotive and construction industry. In Europe, these fibers are produced mainly in France and especially in Aube. To develop agro-composites with high performances, we have focused this thesis on hemp woven. We chose to elaborate the plates with hemp woven and a polypropylene matrix (PP) by compression molding. This work allows us to see the influence of elaboration conditions on the mechanical behavior of these agro-composites. This thesis also allows us to see the effect of aging conditions UV and humidity on the performance of these materials. Finally an analysis of residual stresses determined by the hole drilling method is proposed to see their effects on the agro-materials
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Progresso genético no melhoramento de algodoeiro no Estado de Mato Grosso. / Genetic gain in cotton breeding in Mato Grosso state, Brazil.Edina Regina Moresco 06 June 2003 (has links)
O melhoramento genético vegetal visa a obtenção de novos genótipos que representem algum tipo de ganho comparado aos genótipos em uso pelos agricultores. Para verificar se este objetivo está sendo alcançado, é necessário avaliar o desempenho do programa de melhoramento. Visando quantificar o progresso genético do programa da Embrapa para melhoramento de algodoeiro (Gossypium hirsutum L.) para as condições do estado de Mato Grosso, foram avaliados os dados de 12 anos de pesquisa para os caracteres produtividade de caroço (Kg/ha) e rendimento de fibra (%). Foram utilizadas três metodologias, sendo uma baseada em contrastes entre genótipos comuns em anos consecutivos (metodologia de Vencovsky et al., 1986) (VE), e duas baseadas em regressão linear de médias ajustadas (metodologias de Breseguello, 1998 e de Fonseca Júnior, 1997, respectivamente BR e FJ). Apenas as metodologias de regressão apresentaram estimativas significativas para o progresso genético. Para produtividade (Kg/ha), o progresso genético médio anual obtido pelas metodologias BR e FJ foram respectivamente 3,93% e 3,63%. Já para o caráter rendimento de fibra (%), o progresso genético médio anual para as mesmas metodologias foi respectivamente 0,96% e 1,03%. Os genótipos que apresentaram maior contribuição ao progresso genético para produtividade e rendimento de fibra foram respectivamente a linhagem FMTB 99-03 e a cultivar BRS Cedro. A taxa de substituição de genótipos calculada foi de 55,92%. Com base nos dados obtidos nesta pesquisa, pode-se concluir que após 12 anos de pesquisa no estado de Mato Grosso, o melhoramento genético da Embrapa algodão produziu resultados positivos e significativos, refletido nas estimativas de ganho genético médio. / The main objective of a breeding program is the development of new cultivars, with presents some genetic gain when compared with obsoletes cultivars, allowing farmers to increase their net income. In order to evaluate the performance of genotypes developed by EMBRAPA Cotton Breeding Program carried out in Mato Grosso State, the genetic gain was estimated for yield and lint percent based on 12 years of data set. Three methods were considered for estimation of genetic gain, one based on contrasts among common genotypes (Vencovsky et al., 1986) (VE); and two based on regression of adjusted mean {Breseguello et al., 1998 (BR) and Fonseca Júnior, 1997 (FJ)}. Estimates of genetic gain were positive and significant for the two methods based on regression. The average genetic gain estimated to yield by BR and FJ methods were respectively 3.93% and 3.63%. For lint percent, the average genetic gain estimated by the same methods were 0.96% and 1.03%, respectively. The Genotypes FMTB 99-03 and BRS CEDRO provided the maximum contribution to yield and lint percent, respectively. From the results above and after 12 years of research, it was concluded that Embrapa cotton breeding program in Mato Grosso State achieved positive and significant results which were reflected in a high average of genetic gain estimates.
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Caractérisation de l'interface fibre/matrice : application aux composites polypropylène/chanvre / Fibre/matrix interface characterization : application to hemp fiber/polypropylene compositesNguyen, Duy Cuong 11 May 2016 (has links)
Les agro-composites font l'objet de nombreuses études et applications industrielles en raison des multiples propriétés mécaniques qu'ils présentent. Ces propriétés présentent de grandes perspectives comparées à celles des composites traditionnels. Cependant les connaissances sur le comportement mécanique de l'interface fibre/matrice restent limitées. De plus, la différence de propriété entre la fibre hydrophile et la matrice hydrophobe peut causer des défauts au niveau de l’interface. Il est donc important de caractériser finement la décohésion à l'interface au cours d'une sollicitation. Plusieurs méthodes ont été proposées dans la littérature, elles sont généralement très complexes à mettre en œuvre et sont coûteuses. Dans cette étude, nous avons développé une méthode de caractérisation en se basant sur l'essai de « pull-out ». La géométrie de la fibre a été prise en compte dans le calcul des propriétés mécaniques de l'interface par la mise à profit d'une approche inspirée de la tomographie. L'influence de la température d'élaboration sur les propriétés mécaniques de l'interface a été étudiée de manière à définir la température optimale. L'évolution des propriétés interfaciales a été suivie au cours d'un vieillissement en humidité relative. Après quatre semaines, la résistance au cisaillement et la rigidité au cisaillement de l'interface sont diminuées fortement alors que la déformation à la rupture est augmentée / Agro-composites are increasingly studied and applied to various industries over recent years due to good mechanical properties compared to conventional composites especially in terms of specific values. However, since low adhesion between the hydrophilic fiber and hydrophobic matrix, which occurs one of the main breaks modes in this kind of material, the characterization of the interface becomes a key problem. For investigation of this issue, existing methods show limitation for reasons of complexity (in preparation, in principle) and of cost. In this study, we developed a « pull-out ». In particular, the real fiber geometry of the plant fiber was taken into the calculation of mechanical properties of interface using a tomography inspired method. By checking the effective temperature of the molding then varying it, we studied the effect of this processing parameter to mechanical properties of fibre/matrix interface and determined the optimal conditions. The developed experimental protocol is applied to aged interfaces in order to clarifying the evolution of interfacial properties during the aging time to relative humidity. After four weeks, the interfacial shear strength and the shear modulus of the interface were greatly reduced while the shear deformation at the rupture was greatly increased
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Nitrogênio, potássio e boro: aspectos produtivos, morfológicos, nutricionais e frações fibrosas e proteicas do capim-tanzânia / Nitrogen, potassium and boron: productive, morphological and nutritional parameters, and fiber and protein fractions of Tanzania guineagrassDupas, Elisângela 26 June 2012 (has links)
A adubação equilibrada com nitrogênio, potássio e boro pode alterar a nutrição, produção e valor nutritivo das gramíneas forrageiras. Mediante as aplicações de combinações de doses de nitrogênio, potássio e boro objetivou-se avaliar os efeitos: a) nos aspectos morfológicos, na produção de massa seca e no estado nutricional da parte aérea; b) nas características morfológicas, produtivas e nutricionais das raízes e, c) nos componentes de parede celular e fracionamento de proteínas do capim-tanzânia. O experimento foi conduzido em casa de vegetação no período de janeiro a maio de 2010, utilizando quartzo moído como substrato. Cinco doses de nitrogênio (2, 10, 18, 26 e 34 mmol L-1) foram combinadas com cinco doses de potássio (0,2; 3,1; 6,0; 8,9 e 11,8 mmol L-1), que foram combinadas com cinco doses de boro (0; 45,45; 90,90; 136,35 e 181,80 mol L-1) em fatorial 53 fracionado, perfazendo 23 combinações de nitrogênio, potássio e boro, com quatro repetições. Realizaram-se três cortes das plantas de capim-tanzânia, nos seguintes períodos: 32 dias após o transplantio, 39 dias após o primeiro corte e 45 dias após o segundo corte. As doses de boro não interferiram nos aspectos produtivos e morfológicos da parte aérea e das raízes nem na composição de parede celular e frações proteicas. O boro somente influenciou a concentração de nitrogênio, potássio e boro da parte aérea. A interação doses de nitrogênio x doses de potássio foi significativa para as variáveis número de perfilhos, número de folhas, área foliar, valor SPAD e produção de massa seca da parte aérea. Com o pouco crescimento da planta ocorreu acumulação de nitrogênio, potássio e boro e diluição desses nutrientes nas folhas diagnósticas com a maior produção das plantas. A produção de massa seca das raízes, comprimento total e superfície total aumentaram com as combinações de doses de nitrogênio e potássio. As concentrações de nitrogênio, potássio e boro nas raízes foram influenciadas pela combinação das doses de nitrogênio com potássio. As concentrações de nitrato e amônio foram influenciadas positivamente pela combinação das doses de nitrogênio e potássio, tendo ocorrido maior concentração de amônio do que nitrato nas raízes. Com o aumento das doses de nitrogênio e potássio o comprimento específico e a superfície específica das raízes diminuíram. Os teores de FDN, FDA aumentaram e a relação FE+LM/CB diminuiu com as doses de potássio no segundo e terceiro cortes. O teor de PB no segundo corte aumentou com as doses de nitrogênio e diminuiu com as doses de potássio. As frações proteicas B1+B2 aumentaram e a fração B3 diminuiu no segundo e terceiro cortes com o aumento das doses de nitrogênio. A fração C para o terceiro corte diminuiu com as doses de nitrogênio. A combinação das doses de nitrogênio e potássio aumentou os teores da fração A para o terceiro corte. O suprimento de nitrogênio e potássio proporcionou aumento nos aspectos produtivos, morfológicos e nutricionais da parte aérea e das raízes, além de ter melhorado o valor nutritivo do capim-tanzânia. / The balanced fertilization with nitrogen, potassium and boron may change plant nutrition, yield and nutritive value of forage grass. Through the supply of combinations of nitrogen, potassium and boron it was aimed to evaluate the following effects on Tanzania guineagrass: a) plant morphology, dry matter production and nutritional status in the shoots; b) morphological, productive and nutritional aspects in the roots and c) cell wall components and protein fractions in the shoots. The experiment was conducted in a greenhouse from January to May 2010, using ground quartz as substrate. Five rates of nitrogen (2, 10, 18, 26 and 34 mmol L-1) were combined with five rates of potassium (0.2, 3.1, 6.0, 8.9 and 11.8 mmol L-1) and five rates of boron (0, 45.45, 90.90, 136.35 and 181.8 mol L-1) in 53 fractionated factorial design, which had 23 combinations of nitrogen, potassium and boron, with four replications. Three harvests of Tanzania guineagrass were made: 32 days after transplanting, 39 days after the first harvest and 45 days after the second harvest. Boron rates did not interfere with production and morphological aspects of shoots and roots and in cell wall composition and protein fractions. Boron only influenced the concentration of nitrogen, potassium and boron in the shoots. The interaction nitrogen rates x potassium rates was significant for the number of tillers, number of leaves, leaf area, SPAD value and shoots dry matter production. When plants had short growth, nitrogen, potassium and boron accumulated in plant tissues and those nutrients were diluted in plants with great growth. The dry mass of roots, total root length, total root area increased with the combination of nitrogen and potassium rates. The concentration of nitrogen, potassium and boron were influenced by the combinations of nitrogen and potassium rates. The concentrations of nitrate and ammonium were positively influenced by the combinations of nitrogen and potassium rates, and higher concentrations of ammonium than nitrate were found in root tissues. Root specific length and specific surface area decreased as rates of nitrogen and potassium increased. The NDF and ADF increased and EF+MB/SS ratio decreased with the potassium rates in the second and third harvests. The CP content of the second harvest increased with the nitrogen and decreased with potassium rates. Fractions B1+B2 increased and fraction B3 decreased for the second and third harvests with increasing nitrogen rates. The fraction C for the third harvest decreased with nitrogen rates. The combination of nitrogen and potassium increased the content of fraction A in the third harvest. Nitrogen and potassium supply provided to increase the productive changes, morphological and nutritional aspects in shoots and roots well as it improved the nutritive value of Tanzania guineagrass.
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Nitrogênio, potássio e boro: aspectos produtivos, morfológicos, nutricionais e frações fibrosas e proteicas do capim-tanzânia / Nitrogen, potassium and boron: productive, morphological and nutritional parameters, and fiber and protein fractions of Tanzania guineagrassElisângela Dupas 26 June 2012 (has links)
A adubação equilibrada com nitrogênio, potássio e boro pode alterar a nutrição, produção e valor nutritivo das gramíneas forrageiras. Mediante as aplicações de combinações de doses de nitrogênio, potássio e boro objetivou-se avaliar os efeitos: a) nos aspectos morfológicos, na produção de massa seca e no estado nutricional da parte aérea; b) nas características morfológicas, produtivas e nutricionais das raízes e, c) nos componentes de parede celular e fracionamento de proteínas do capim-tanzânia. O experimento foi conduzido em casa de vegetação no período de janeiro a maio de 2010, utilizando quartzo moído como substrato. Cinco doses de nitrogênio (2, 10, 18, 26 e 34 mmol L-1) foram combinadas com cinco doses de potássio (0,2; 3,1; 6,0; 8,9 e 11,8 mmol L-1), que foram combinadas com cinco doses de boro (0; 45,45; 90,90; 136,35 e 181,80 mol L-1) em fatorial 53 fracionado, perfazendo 23 combinações de nitrogênio, potássio e boro, com quatro repetições. Realizaram-se três cortes das plantas de capim-tanzânia, nos seguintes períodos: 32 dias após o transplantio, 39 dias após o primeiro corte e 45 dias após o segundo corte. As doses de boro não interferiram nos aspectos produtivos e morfológicos da parte aérea e das raízes nem na composição de parede celular e frações proteicas. O boro somente influenciou a concentração de nitrogênio, potássio e boro da parte aérea. A interação doses de nitrogênio x doses de potássio foi significativa para as variáveis número de perfilhos, número de folhas, área foliar, valor SPAD e produção de massa seca da parte aérea. Com o pouco crescimento da planta ocorreu acumulação de nitrogênio, potássio e boro e diluição desses nutrientes nas folhas diagnósticas com a maior produção das plantas. A produção de massa seca das raízes, comprimento total e superfície total aumentaram com as combinações de doses de nitrogênio e potássio. As concentrações de nitrogênio, potássio e boro nas raízes foram influenciadas pela combinação das doses de nitrogênio com potássio. As concentrações de nitrato e amônio foram influenciadas positivamente pela combinação das doses de nitrogênio e potássio, tendo ocorrido maior concentração de amônio do que nitrato nas raízes. Com o aumento das doses de nitrogênio e potássio o comprimento específico e a superfície específica das raízes diminuíram. Os teores de FDN, FDA aumentaram e a relação FE+LM/CB diminuiu com as doses de potássio no segundo e terceiro cortes. O teor de PB no segundo corte aumentou com as doses de nitrogênio e diminuiu com as doses de potássio. As frações proteicas B1+B2 aumentaram e a fração B3 diminuiu no segundo e terceiro cortes com o aumento das doses de nitrogênio. A fração C para o terceiro corte diminuiu com as doses de nitrogênio. A combinação das doses de nitrogênio e potássio aumentou os teores da fração A para o terceiro corte. O suprimento de nitrogênio e potássio proporcionou aumento nos aspectos produtivos, morfológicos e nutricionais da parte aérea e das raízes, além de ter melhorado o valor nutritivo do capim-tanzânia. / The balanced fertilization with nitrogen, potassium and boron may change plant nutrition, yield and nutritive value of forage grass. Through the supply of combinations of nitrogen, potassium and boron it was aimed to evaluate the following effects on Tanzania guineagrass: a) plant morphology, dry matter production and nutritional status in the shoots; b) morphological, productive and nutritional aspects in the roots and c) cell wall components and protein fractions in the shoots. The experiment was conducted in a greenhouse from January to May 2010, using ground quartz as substrate. Five rates of nitrogen (2, 10, 18, 26 and 34 mmol L-1) were combined with five rates of potassium (0.2, 3.1, 6.0, 8.9 and 11.8 mmol L-1) and five rates of boron (0, 45.45, 90.90, 136.35 and 181.8 mol L-1) in 53 fractionated factorial design, which had 23 combinations of nitrogen, potassium and boron, with four replications. Three harvests of Tanzania guineagrass were made: 32 days after transplanting, 39 days after the first harvest and 45 days after the second harvest. Boron rates did not interfere with production and morphological aspects of shoots and roots and in cell wall composition and protein fractions. Boron only influenced the concentration of nitrogen, potassium and boron in the shoots. The interaction nitrogen rates x potassium rates was significant for the number of tillers, number of leaves, leaf area, SPAD value and shoots dry matter production. When plants had short growth, nitrogen, potassium and boron accumulated in plant tissues and those nutrients were diluted in plants with great growth. The dry mass of roots, total root length, total root area increased with the combination of nitrogen and potassium rates. The concentration of nitrogen, potassium and boron were influenced by the combinations of nitrogen and potassium rates. The concentrations of nitrate and ammonium were positively influenced by the combinations of nitrogen and potassium rates, and higher concentrations of ammonium than nitrate were found in root tissues. Root specific length and specific surface area decreased as rates of nitrogen and potassium increased. The NDF and ADF increased and EF+MB/SS ratio decreased with the potassium rates in the second and third harvests. The CP content of the second harvest increased with the nitrogen and decreased with potassium rates. Fractions B1+B2 increased and fraction B3 decreased for the second and third harvests with increasing nitrogen rates. The fraction C for the third harvest decreased with nitrogen rates. The combination of nitrogen and potassium increased the content of fraction A in the third harvest. Nitrogen and potassium supply provided to increase the productive changes, morphological and nutritional aspects in shoots and roots well as it improved the nutritive value of Tanzania guineagrass.
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