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1
Rjiba, Narjes. "Fibre de coton : microstructures et propriétés de surface." Mulhouse, 2007. http://www.theses.fr/2007MULH0873.
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Le principal objectif de ce travail était de caractériser d'un point de vue physico-chimique la surface de la fibre de coton. Une fibre brute et une fibre extraite à l'éthanol ont été analysées. Cette caractérisation a été principalement menée par chromatographie gazeuse inverse (IGC), permettant de déterminer l'énergie de surface de ces fibres en fonction de la température ainsi que leur morphologie de surface à une échelle moléculaire, avant et après traitement. Il a été montré que l'énergie de surface de la fibre brute dépend fortement de la présence de cires et de pectines qui recouvrent un tel type de fibre. En particulier, la fusion des cires en surface des fibres est nettement mise en évidence dans une gamme de températures comprises entre 50 et 90°C. La nano-morphologie de la surface de la fibre de coton est aussi très affectée par la présence des cires : une extraction à l'éthanol conduisant à une surface plus homogène d'un point de vue topographique. Dans la de Kième partie de ce travail, pour confirmer les résultats obtenus par IGC, la fibre de coton a été caractérisée par d'autres techniques microscopiques (microscopies électronique et à force atomique) et spectroscopiques (spectroscopie de photoélectrons, spectroscopies vibrationnelles,. . . )The aim of this work was to characterize the surface of the cotton fibre from a physical and chemical point of view. Raw and ethanol extracted fibres were particularly analysed. This characterization was mainly performed by means of inverse gas chromatography (IGC), which allowed us to determine the surface energy of the fibres as a function of temperature as well as their surface morphology at a molecular scale, before and alter treatment. It was shown that the thermodynamic surface energy of the raw cotton fibre strongly depends on the presence of waxes and pectins which usually cover such a type of fibre. In particular, the melting of waxes on the fibre surface, in a range of temperatures from 50 to 90°C, is clearly pointed out. The nano-morphological aspects of the cotton fibre surface are also greatly affected by the presence of waxes: ethanol extraction leading to a more homogeneous surface from a topographical point of view. To confirm the results obtained by IGC, the characterization of cotton fibres was completed, in the second part of this work, by means of other microscopical (electronic and atomic force microscopies ) and spectroscopie (X-ray photoelectron spectroscopy, vibrational spectroscopies,. . . ) techniques
2
Kamenopoulou, Vassiliki. "Proprietes dosimetriques des fibres textiles : application a la dosimetrie par resonance paramagnetique electronique d'un accident d'irradiation gamma." Toulouse 3, 1987. http://www.theses.fr/1987TOU30172.
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Nowrouzieh, Shahram. "Etude des phénomènes de cohésion et friction inter fibre : cas du coton." Mulhouse, 2007. http://www.theses.fr/2007MULH0896.
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Les fibres textiles sont couramment caractérisées par beaucoup de paramètres liés à la longueur, à la finesse, à la maturité, à la ténacité, etc. Cependant peu d'études concernent la caractérisation de l'état de surface de ces fibres ou ses propriétés frictionnelles. Ceci est davantage visible dans les études reliant les propriétés du fil à celles des fibres qui le composent. Dans ce cadre, le but de cette étude était, d'une part, de concevoir un dispositif expérimental simple et fiable pour caractériser le frottement inter-fibre et, d'autre part, d'établir par son intermédiaire des tendances de relations entre les caractéristiques des fibres et des fils. Nous avons commencé par concevoir un appareil simple de mesure de la force nécessaire pour dissocier un ruban sous pression inter-fibre contrôlée. Il est composé de deux chariots identiques, un des chariots est fixe, tandis que l'autre glisse sur un rail et se déplace à vitesse constante. Nous avons testé notre dispositif à différentes charges, vitesses et titres de ruban. Les études ont montré que dans le domaine expérimental utilisé, l'effet de la vitesse était négligeable alors que l'effet de la charge était hautement significatif. Le modèle qui décrit la force de frottement est inspiré par celui de Bowden et Tabor dans lequel la force de frottement et la charge normale sont normalisés par le nombre de fibres dans le ruban. Ce modèle a été validé dans un deuxième temps par une campagne d'essais sur 1 1 cotons différents. Cette deuxième étude a mis en évidence des pistes très intéressantes concernant l'effet du frottement sur les caractéristiques du fil, notamment sur sa ténacité. En effet, la force du frottement n'intervient pas directement sur la ténacité du fil, mais affecte de façon directe les paramètres de régularité du fil et se sont ces derniers qui déterminent en partie la ténacité du filThe textile fibres are commonly characterized by many parameters related to the length, fineness, maturity, tenacity, and so, on. But few studies related tc, the characterization of the surface properties of these fibres or their frictional properties. This is more clearly seen in the studies relating the yarn and the fibre properties. In this côntext, the purpose of this study was, first, to design a simple and reliable device to characterize the inter-fibre friction and, secondly, to establish, by the means of the inter fibre frictional properties, some trends of relations between the fibre and yarn characteristics. We started by designing a simple device for measuring the force required to break a sliver under controlled inter-fibre pressure. It consists of two identical carriages, one is fixed, while the Cher slides on a rail and is moving at a constant speed. We tested our device at different loads, speeds and sliver count. The results have shown that in our experimental domain, the effect of speed was negligible while the effect of the load was highly significant. The model that describes the friction force is inspired by that of Bowden and Tabor in which the frictional force and the normal charge are normalized by the number of fibres in the sliver. This model was validated in a second stage by a series of tests on 1 1 different cottons. This second study highlighted some very interesting idea on the effect of friction on the yarn characteristics, especially on his tenacity. Really, the friction force does not affect directly the yarn tenacity, but directly affects the regularity parameters of the yarn and these last, which determine party the yarn tenacity
4
Aboe, Modeste. "Etude de la variabilité intra-balle des caractéristiques technologiques des fibres de coton produites en Afrique de l'Ouest et du Centre." Phd thesis, Université de Haute Alsace - Mulhouse, 2012. http://tel.archives-ouvertes.fr/tel-00718836.
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Grâce aux développements techniques et technologiques des dernières décennies, le commerce international du coton passe graduellement d'un classement manuel et visuel à un classement à base de résultats de mesures instrumentales. Or adopter une technique requiert d'en étudier ses modalités et ses conditions d'utilisation. Aux USA, des études périodiques de variabilité permettent d'assortir ces résultats d'analyse de tolérances commerciales afin de limiter la fréquence des litiges. Adopter en Afrique les règles et les méthodes de mesure des USA exposerait à un risque de litige accru si les conditions de production déterminent un coton de qualité plus variable. Pour la première fois en Afrique, nous avons mené une étude de la variabilité des caractéristiques technologiques des fibres dans huit pays d'Afrique de l'Ouest et du Centre : Bénin, Burkina-Faso, Cameroun, Côte d'Ivoire, Mali, Sénégal, Tchad et Togo. Pendant deux saisons de production, nous avons réalisé une expérimentation à trois types de prélèvements de fibres : 1) huit échantillons par balle au sein de 215 balles produites dans 27 usines d'égrenage, 2) un échantillon par balle de 4286 balles constituées en séries de 200 balles consécutives en saison 1 et de 100 balles consécutives en saison 2 dans les mêmes usines, 3) deux échantillons par balle (un en haut et un en bas) sur 817 balles constituées en séries de vingt balles consécutives hebdomadairement dans cinq usines au cours de la saison 2. Ensuite, les échantillons des 5318 balles échantillonnées furent analysés sur une Chaîne de Mesures Instrumentales (CMI) dans un laboratoire respectant les recommandations internationales et les conditions d'ambiance contrôlées. L'analyse statistique des données recueillies a permis d'évaluer le niveau de variabilité de chacune des caractéristiques technologiques étudiées, au sein des balles et entre celles-ci. Une méthode d'échantillonnage et de réalisation des analyses sur CMI est proposée pour réaliser le classement des balles de coton d'Afrique de l'Ouest et du Centre à partir de résultats précis et répétables respectant les règles commerciales établies au niveau mondial.
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Hernàndez, Hernàndez Valeria. "Interaction between turgor pressure and plasmodesmata permeability." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSEN076.
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Les cellules végétales sont entourées par une paroi cellulaire rigide, ce qui qui exclut des processus essentiels au développement animal, comme la migration cellulaire et le réarrangement des tissus. Au lieu de cela, le développement des plantes repose sur la division et l'expansion cellulaires. Le paradigme actuel suppose que l’expansion cellulaire dépend des propriétés biomécaniques de la paroi cellulaire et de la génération de la pression de turgescence. Les plasmodesmes sont des canaux membranaires qui relient des cellules voisines et permettent la libre circulation des molécules plus petites que leur diamètre (définissant leur perméabilité). Il est établi que la perméabilité des plasmodesmes change au cours du développement de la plante et que ces modifications peuvent affecter le mouvement des sucres. Pour cette raison, la perméabilité des plasmodesmes semble être un bon candidat pour la régulation de la pression de turgescence lors de l'expansion cellulaire, cependant, son rôle reste largement inexploré. Ainsi, des études antérieures suggèrent que les plasmodesmes peuvent répondre aux changements de pression de turgescence. Dans ce travail, nous avons avancé l'hypothèse selon laquelle la pression de turgescence et la perméabilité des plasmodesmes pourraient s’influence au cours du développement de la plante. Nous avons abordé ce problème en mettant tout d'abord en avant un réseau d'interactions entre différents facteurs cellulaires et moléculaires susceptibles de médier ces rétroactions entre la turgescence et les plasmodesmes. Deuxièmement, nous avons généré un modèle informatique pour explorer une direction de ces interactions: le rôle de la perméabilité des plasmodesmes sur la régulation de la pression de turgescence. Notre modèle utilise les équations de Lockhart décrivant l’expansion cellulaire irréversible, auxquelles sont ajoutées les flux d'eau et de solutés à travers les plasmodesmes. Nous avons utilisé la fibre de coton comme système d’étude car il s’agit d’une cellule unique qui ne se divise pas et qui augmente généralement en longueur. De plus, des études expérimentales antérieures dans ce système ont montré une corrélation entre la fermeture de plasmodesmes et des valeurs maximales de la pression de turgescence. Les résultats de notre modèle suggèrent que la perméabilité des plasmodesmes est en effet un facteur clé dans la régulation de la turgescence et de la croissance de la fibre du coton. De plus, nous suggérons que des changements dynamiques de la perméabilité des plasmodesmes soient nécessaires pour récupérer les comportements de pression de turgescence qui ont été rapportés expérimentalementPlant cells are surrounded by the rigid cell wall that precludes developmental processes that are central in animal development, like cell migration and tissue rearrangement. Instead, plant development relies on cell division and expansion. The current paradigm assumes that cell expansion depends on the biomechanical properties of the cell wall and on the generation of turgor pressure. Plasmodesmata are membrane-lined channels that connect neighboring cells and allow free movement of molecules that are smaller than their diameter (i.e., permeability). It is known that plasmodesmal permeability changes during plant development and that these modifications can affect movement of sugars. Because of this, plasmodesmal permeability seems to be a good candidate for the regulation of turgor pressure during cell expansion, however, its contribution remains largely unexplored. In turn, previous studies suggest that plasmodesmata may respond to changes in turgor pressure. In this work we put forward the hypothesis that turgor pressure and plasmodesmal permeability may affect each other during plant development. We addressed this problem by, first, putting forward a network of interactions between different cellular and molecular factors that might mediate these feedbacks between turgor and plasmodesmata. Second, we generated a computational model to explore one direction of these interactions: the role of plasmodesmal permeability on turgor pressure regulation. Our model uses Lockhart's equations for irreversible cell expansion with addition of plasmodesmal-dependent fluxes of water and solutes. We used cotton fiber as a study system because it is a single cell without division that mostly increases in length. Furthermore, previous experimental studies in this system have correlated closure of plasmodesmata with peak values of turgor pressure. The results of our model suggest that plasmodesmal permeability is, indeed, a key factor in regulating turgor and cotton fiber growth. Moreover, we suggest that dynamical changes of plasmodesmal permeability are needed in order to recover turgor pressure behaviors that have been experimentally reported. Finally, we explored with our collaborators the potential contribution of plasmodesmal permeability in the evolution of complex multicellular plants using the "Dynamical Patterning Modules" (DPMs) framework. These ideas can be useful in understanding how plant body plans originated
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Zhao, Yifang. "La fixation des colorants réactifs au coton aux moyens du rayonnement infrarouge = Fixation of reactive dyes on cotton using infrared radiation." Sherbrooke : Université de Sherbrooke, 2000.
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7
Hernandez-Gomez, Mercedes Clara. "Cell walls and cotton fibre development." Thesis, University of Leeds, 2015. http://etheses.whiterose.ac.uk/11458/.
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Bel, Patricia Damian. "Cotton quality - fibre to fabric: fibre properties relationships to fabric quality." University of Southern Queensland, Faculty of Engineering and Surveying, 2004. http://eprints.usq.edu.au/archive/00003193/.
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[Abstract]: The textile industry has a recurrent white speck nep problem in cotton. “White specks” are immature clusters of fibres that are not visible as defects until dyeing, after which they remain white on the surface of a darkly dyed fabric, or appear as non uniform streaks in the fabric. Both results render the fabric unsuitable for commercial fashion fabrics. The white speck potential of cotton is difficult to predict except in extremely immature cottons. Competitive synthetic fibres are uniform in length and strength and never have a maturity problem resulting in dye defects. They are much more predictable in the mill. As a result, cotton faces the risk of being replaced by synthetic fibres. Industry requires a method to predict fabric quality from cotton bale fibre properties to minimize this risk. This research addresses the problem of predicting white specks in dyed cotton fabrics. It is part of a large study, which is supported jointly by US and Australian agencies. The main objective is to predict fabric quality from bale fibre properties given controlled gin and mill processing. Gin and mill processing must be controlled so that field and varietal effects can be seen without the interaction of mechanical processing differences. This results in achieving other objectives, including the provision of baseline data for Australian varieties, ginning effects and comparison of ring and open-end spinning. Initially a reliable method for measuring white specks had to be found. Several systems have been evaluated and are reported here. The systems accuracy was compared using fabrics from the US Extreme Variety Study (EVS), which was grown specifically to have different levels of white specks. The fabrics made from the US (Leading Variety Study 1993 (LVS) and The American Textile Manufacturers Institute (ATMI) Cotton Variety Processing Trials, 2001) and the Australian (1998 & 1999) variety studies were analysed using AutoRate-2-03, the best of the image analysis systems studied. The final release of AutoRate (February 2003) was developed by Dr. Bugao Xu to measure white specks on dark fabrics in conjunction with this research. This final analysis of these studies results in white speck prediction equations from high-speed fibre measurement systems. This information should be immediately useful to as a tool to measure the effects of field and ginning practices on the levels of white specks without having to carry the research out to finished fabrics. Cotton breeders will be able to use the equations in the development of new varieties with low white speck potential, by eliminating varieties with high white speck potential early on. The research will continue on a much larger scale in the US and hopefully a WSP (White Speck Potential) value will be incorporated into the US Cotton Grading System.
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Bissou, Billong Julienne. "Fixation thermique par rayonnement infrarouge des colorants réactifs sur les fibres de coton d'un tissu fait de coton/polyester." [S.l. : s.n.], 2003.
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10
McGinley, Susan. "Keys to Cotton Fiber Strength." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 1993. http://hdl.handle.net/10150/622333.
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Belmasrour, Rachid. "The Distribution of Cotton Fiber Length." ScholarWorks@UNO, 2010. http://scholarworks.uno.edu/td/1216.
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By testing a fiber beard, certain cotton fiber length parameters can be obtained rapidly. This is the method used by the High Volume Instrument (HVI). This study is aimed to explore the approaches and obtain the inference of length distributions of HVI beard sam- ples in order to develop new methods that can help us find the distribution of original fiber lengths and further improve HVI length measurements. At first, the mathematical functions were searched for describing three different types of length distributions related to the beard method as used in HVI: cotton fiber lengths of the original fiber population before picked by the HVI Fibrosampler, fiber lengths picked by HVI Fibrosampler, and fiber beard's pro-jecting portion that is actually scanned by HVI. Eight sets of cotton samples with a wide range of fiber lengths are selected and tested on the Advanced Fiber Information System (AFIS). The measured single fiber length data is used for finding the underlying theoreti-cal length distributions, and thus can be considered as the population distributions of the cotton samples. In addition, fiber length distributions by number and by weight are dis- cussed separately. In both cases a mixture of two Weibull distributions shows a good fit to their fiber length data. To confirm the findings, Kolmogorov-Smirnov goodness-of-fit tests were conducted. Furthermore, various length parameters such as Mean Length (ML) and Upper Half Mean Length (UHML) are compared between the original distribution from the experimental data and the fitted distributions. The results of these obtained fiber length distributions are discussed by using Partial Least Squares (PLS) regression, where the dis-tribution of the original fiber length from the distribution of the projected one is estimated.
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Benians, Thomas Anthony Scott. "In situ analysis of cotton fibre cell wall polysaccharides." Thesis, University of Leeds, 2012. http://etheses.whiterose.ac.uk/5433/.
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The cotton fibre is one of the most economically important cells in the world. Each year, over 25 million tonnes are harvested and the industry is responsible for 300 million jobs world-wide, with revenues of over $120 billion in the USA alone. For such an important cell there is little known about its cell wall composition as well as the functional roles of these polysaccharides during fibre development. Although much work has already been done on the cotton fibre transcriptome, a study of cell wall composition during development and maturation is crucial in linking these data to further understand fibre differentiation. This research explored the developmental biology of the cotton fibre in relation to key polysaccharide structures and architectural properties in the context of cell wall development. This has been achieved by the development of methodologies for the detection and imaging of low level polysaccharide epitopes of the cotton fibre using molecular probes known as monoclonal antibodies (mABs) and carbohydrate-binding modules (CBMs), directed in-situ to these glycans. Key polysaccharide changes were observed during fibre development, maturity and processing. Upon maturity, pectic homogalacturonan and xyloglucan were readily detectable at the surface of fibres after removal of the waxy outer layer. Other polysaccharides including arabinan, xylan and mannan, as well as cell wall glycoproteins were detected after treatments that removed the pectin-rich primary cell wall layer. This research shows that cell wall probes are powerful and useful tools to study cotton fibres throughout development, maturity and processing in the context of cell wall biology, though these polysaccharide changes need to be explored one by one to establish structure-function relationships. With the upcoming sequencing of the G. hirsutum genome, cotton fibre research will be an exciting field and the work presented here will provide a base for future studies, with potential for the manipulation of key developmental polysaccharides to alter the final fibre properties. The ultimate goal of improving cotton fibre properties will have significant economic, ecological and societal impacts for decades to come.
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Mir, Youssef. "La fixation simultanée d'un mélange de deux colorants réactifs et dispersés sur un tissu de coton/polyester par rayonnement infrarouge et air chaud." Sherbrooke : Université de Sherbrooke, 2002.
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Coleman, Leana. "Dietary fat and fibre alters colon risk in the rat /." Title page and abstract only, 1999. http://web4.library.adelaide.edu.au/theses/09SB/09sbc692.pdf.
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Braden, Chris Alan. "Inheritance of cotton fiber length and distribution." Texas A&M University, 2005. http://hdl.handle.net/1969.1/4355.
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Fiber quality data from five upland cotton (Gossypium hirsutum L.) genotypes,
which were grown at College Station, TX during 2001 and 2002, were subjected to
diallel and generation means analyses to determine the potential for improvement of
fiber length and to determine the inheritance of length distribution data. Four near-long
staple (NLS) upland cotton genotypes and one short-staple genotype were crossed in all
combinations, excluding reciprocals. Estimates of general (GCA) and specific
combining ability (SCA) for fiber length based on GriffingâÂÂs diallel Model I, Method 4
were calculated for high volume instrumentation (HVI) upper-half mean (UHM) fiber
length and advance fiber information system (AFIS) mean fiber length by weight (FLw),
mean fiber length by number (FLn), upper quartile length by weight (Uqlw), fiber length
distribution cross entropy (using 3 different standard or check distributions - CEA, CEB,
and CEC), fiber length distribution kurtosis (FLwKurt), and fiber length distribution
skewness (FLwSkew) for FLw. Across environments, GCA effects were significant for
fiber length measurements of UHM, FLw, FLn, Uqlw, and SFCw and distribution
measurements of CEA, CEB, FLwKurt, and FLwSkew. On the basis of GCA effects, TAM 94L-25 was the best parent to be used in a cross to improve upland fiber length,
while Acala 1517-99 was the parent of choice to improve distribution among the 4
parents tested.
The inheritance of AFIS fiber length measurements and distribution data was
estimated using parents, F1, F2, and backcross generations. The magnitude and
significance of the estimates for non-allelic effects in the parental combinations suggest
that epistatic gene effects are present and important in the basic mechanism of AFIS
fiber length and length distribution inheritance for the populations studied. Gene effects
and variances for all AFIS fiber length and distribution data measurements were
inherited differently in different environments and specific parental combination,
suggesting environmentally specific mechanisms. Developing genotypes with enhanced
fiber length and an optimal fiber length distribution should be a priority to improve
spinning performance and product quality of U.S. upland cotton.
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Bissou, Billong Julienne. "Fixation thermique par rayonnement infrarouge des colorants réactifs sur les fibres de coton d'un tissu fait de coton/polyester." Mémoire, Université de Sherbrooke, 2002. http://savoirs.usherbrooke.ca/handle/11143/1221.
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L'utilisation de l'infrarouge pour la fixation des colorants demeure toutefois une technique moins développée dans le domaine du textile. C'est pourquoi une étude portant sur la fixation des colorants réactifs sur les fibres de coton, dans le cas d'un mélangé de fibres coton/polyester est réalisée. Deux recettes des mélanges de colorants réactifs (vert forêt et rouge bourgogne) ont été utilisées à cette fin. L'influence de paramètres physiques (vitesse, puissance) et chimiques (type de base et quantité, ajout ou non de sels) sur le rendement de la fixation sont étudiés. Le choix de ces paramètres physiques et chimiques est guidé par des mesures de rendement de fixation dans diverses conditions en comparaison avec le mode de fixation à froid. La méthode de fixation thermique étudiée consiste en un chauffage par rayonnement infrarouge (IR) suivi d'une cuisson à l'air chaud dans une unité chauffante (UC). Le second volet de l'étude a été la mise sur pied d'un mode de fixation qui puisse opérer de façon continue. Cette deuxième partie a permis de constater que pour une température basse, la fixation est faible."--Résumé abrégé par UMI.
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Celikbag, Yusuf El Mogahzy Yehia. "Developing methods for detecting cotton fiber identity theft." Auburn, Ala., 2009. http://hdl.handle.net/10415/1768.
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Sjöblom, Therése. "Fabric conditioning for more gentle shredding : Pre-treatment for mechanical recycling of cotton and polyester." Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-14875.
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There is a growing need for fibres with increasing population. One way to solve this is to recycle the fibres from textile waste. In mechanical recycling by shredding the textiles are shredded back to fibrous form. The biggest problem with shredding is that it is a harsh process that reduces the fibre length and damages the fibre. To make the shredding process more gentle and preserve more of the fibre length, pre-treatment that lowers the friction between the fibres have been investigated. Polyethene glycol 4000 (PEG 4000) is an environmentally friendly chemical that could be used to lower the friction of cotton and polyester, the two most used textile fibres. Another treatment evaluated is glycerol. The treatment should not affect further processing of the fibres. For evaluating the treatment, a test of the interfibre friction was performed on carded webs and fabrics that were untreated and treated. Prior to shredding four samples were made of fabrics of cotton, polyester and polycotton. From each fabric, one was left untreated, and one was treated with a low concentration of PEG 4000. The concentration of PEG 4000 was chosen from the test on fibres. Also from each fabric, two treatments that were not prepared by the author; one with a high concentration of PEG 4000 and the other with glycerol. All 12 samples were shredded back to fibres. The shredded material was analysed, and the fibre length was measured. The reclaimed fibres from the shredded material were also tried to be processed into yarns. The main result was that it was possible to rotor spin yarn of 100% reclaimed fibres from cotton and polyester treated with PEG 4000, which means that the treatment did not interfere with the spinnability of the reclaimed fibres. Untreated cotton was also spinnable, but untreated polyester was not possible to card. The cotton and polyester treated with glycerol were possible to carded and made into a sliver but not spinnable. The reclaimed fibres from the polycotton fabric were not possible to card or process further. This result correlates with the analyses of the shredded material and the fibre length measurement. The best results were for polyester treated with 0.71 w% PEG 4000 that had 121% longer mean fibre length than untreated polyester. The best result for cotton was treated with 0.29 w% PEG 4000.
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Al-Dhahir, S. K. A. "Toxicological properties of vegetable fibre dusts : Studies of the acute effects of Cotton dust and cotton dust polymer." Thesis, Cardiff University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383124.
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Chollakup, Rungsima. "Etude des mélanges soie-coton en filature fibres courtes : caractéristiques des fils et analyse sonsorielle des tricots." Mulhouse, 2003. http://www.theses.fr/2003MULH0745.
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Cette étude a pour but la valorisation des sous-produits de l'industrie de la soie grège et soie schappe. L'objectif principal est l'étude détaillée des effets des facteurs de mélange dans la filature des fibres sourtes. Ces facteurs sont : le type de mélange, dans la phase de la grosse préparation ou dans le banc d'étirage ; le type de sous-produits, les frisons, les bourres de la filature et le cocon coupé, qui représentent respectivement la partie externe, la partie moyenne et l'ensemble des cocons de soie ; et la proportion de la soie, 0, 25, 50, 75 et 100 %. Les fils produits sont de 15, 30 et 50 tex. Les propriétés physiques des fibres de soie et coton sont étudiées avant de procéder a différents mélanges. Ensuite, une étude globale et complète de l'influence des facteurs de mélange sur les caracté̀ristiques des fibres et des fils, ainsi que l'analyse sensorielle des tricots produits avec ces fils est réalisée. Il a été de plus montré que dans la section transversale du fil, la soie tend légèrement à migrer à l'intérieur du fil.
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Clipson, J. A. "The preparation, properties and dyeing behaviour of differential-dyeing cellulose." Thesis, Nottingham Trent University, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378970.
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Silvertooth, J. C. "Recent Yield and Fiber Micronaire Tendencies for Upland Cotton in Arizona." College of Agriculture, University of Arizona (Tucson, AZ), 2001. http://hdl.handle.net/10150/211312.
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Problems associated with increasing trends towards high micronaire values for Upland cotton (Gossypium hirsutum L.) have been a matter of concern for the Arizona cotton industry in recent years. The discounts on fiber value associated with high micronaire has been compounded by the fact that market prices for cotton fiber has been very low in recent years and yields have been stable at best. An evaluation of recent yield and fiber quality data from a number of locations in Arizona was evaluated in relation to trends within Arizona and across the U.S. cotton belt. Results indicate similar patterns exist in terms of stable yields (yield plateau) and increasing micronaire values between Arizona and other U.S. cotton producing states. The conclusion is presented that these patterns are at least due in part to a common genetic base for varieties that grown in Arizona and beltwide. There also appears to be some distinct relationships associated with high micronaire with region and individual farm management practices.
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Aronsson, Julia. "Torn to be worn? : Cotton fibre length of shredded post-consumer garments." Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-12380.
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In 2015 the global fibre consumption was 96.7 million tonnes, which is an increase of 3.1% from the year before. Our high textile consumption has led to an increasing demand of raw materials and generation of textile waste. Only in Europe, a total amount of 4.3 million tonnes of apparel waste each year is sent to either incineration or landfills. Approximately 50% of the clothes we discard and donate are composed of cotton. In the future, the cotton production is predicted to stagnate since the world population is increasing and arable land to greater extent will be needed for food production. Thereby, it is important that we utilize the cotton waste generated. One of the most commonly used processes for recycling textile waste is the shredding process. In this method, textile waste is shredded back into their constituent fibres. The drawback with the shredding process is that the fibre length is reduced. The fibre length is an important property since it has a high influence on textile processing such as yarn production and final product quality. The aim of this thesis was to investigate how post-consumer cotton garments with different degree of wear affects the fibre length obtained in the shredding process. This was performed by analysing the input fibre length as well as the output fibre length. Additionally, several parameters were investigated: fabric construction and yarn structure. Degree of wear was categorized into two levels: low and high degree of wear. The fabric constructions used in this study were single-jersey and denim. The yarn structure were analysed in terms of yarn count, yarn twist and manufacturing process. The result showed that the fibre length before shredding was statistically significant longer for the materials with low degree of wear compared to high degree of wear. After shredding, it was shown that the fibre length reduction was lower for the materials with high degree of wear. This indicates that longer fibres give higher fibre length reduction. In addition, it was found that finer yarn gives higher fibre length reduction. The result also showed that the yarn manufacturing process has a great influence on the ease of shredding and the fibre length obtained in the end. Based on the result in this thesis it can be concluded that the shredding process needs to be improved in order to preserve the fibre length. The area of post-consumer textile waste is complex and the result showed that there is many underlying parameters that need to be taken into account to further develop the shredding process.
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Silvertooth, J. C., A. Galadima, E. R. Norton, and R. Tronstad. "Evaluation of Crop Management Effects on Fiber Micronaire, 2000." College of Agriculture, University of Arizona (Tucson, AZ), 2001. http://hdl.handle.net/10150/211310.
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Arizona has experienced a trend toward increasing fiber micronaire values in recent years resulting in substantial discounts on fiber value. There is some evidence to suggest management can impact fiber micronaire. Approximately 250 cases were identified in cotton production areas in Arizona ranging from the lower Colorado River Valley to near 2,000 ft. elevation with grower cooperators in the 2000 season. Field records were developed for each field by use of the University of Arizona Cotton Monitoring System (UA-CMS) for points such as variety, planting date, fertility management, irrigation schedules, irrigation termination, defoliation, etc. Routine plant measurements were conducted to monitor crop growth and development and to identify fruiting patterns and retention through the season. As the crop has approached cutout and the lower bolls began to open, open boll samples have been collected from the lowest four, first position bolls (theoretically the bolls with the highest micronaire potential on the plant) from 10 plants, ginned, and the fiber analyzed for micronaire (low 4). From that point forward, total boll counts per unit area and percent open boll measurements are being made on 14-day intervals until the crop is defoliated. Following defoliation, final plant maps were performed. Relationships among low 4 samples micronaire, irrigation termination (IT), defoliation, and final crop micronaire were analyzed.
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Wang, Rui. "Site-specific prediction and measurement of cotton fiber quality." Diss., Mississippi State : Mississippi State University, 2004. http://library.msstate.edu/etd/show.asp?etd=etd-10122004-220250.
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Silvertooth, J. C., A. Galadima, and R. Tronstad. "Irrigation Termination Effects on Cotton Yield and Fiber Quality." College of Agriculture, University of Arizona (Tucson, AZ), 2006. http://hdl.handle.net/10150/198213.
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Field experiments were conducted in 2004 and 2005 at the University of Arizona Maricopa Agricultural Center (1,175ft. elevation) to evaluate the effects of five irrigation termination (IT1, IT2, IT3, IT4, and IT5) dates on yield and fiber micronaire of eleven Upland cotton varieties and one Pima variety. In addition, the economic relationships of IT treatments were also evaluated. The experimental design was a split plot in a randomized complete block design with three replications. The main treatments included the five IT dates and the subunits consisted of 11 Upland varieties and a Pima variety. The first two IT treatments (IT1 and IT2) were imposed with the intention of terminating irrigations very early and pre-maturely at peak bloom. Based upon current UA recommendations for IT to complete a single cycle fruit set, the more optimal date of IT would have included one or two additional irrigations (beyond IT1 and IT2). In this experiment, IT2 was structured to provide an additional (one) irrigation just past peak bloom. For the IT3 plots, the intention was to attempt to time termination in advance of cutout. The 2004 and 2005 IT4 and IT5 were imposed to attempt to complete the primary fruiting cycle development and produce a second cycle fruit set that require irrigations until late August and late September, respectively. In general, lint yield and micronaire results revealed significant differences among the IT treatments and varieties. In a similar fashion to a previous set of IT experiments (2000-2002), lint yield and micronaire values consistently increased with later IT dates. The best combined lint yield and micronaire results were achieved with IT4 date, which received 12 and 18 in. less irrigation water than IT5 in 2004 and 2005, respectively. In 2004 and 2005, the 12 and 18 in. water saved equate to approximately 20% and 30% less water used under the conventional practice, respectively. The average marginal value of water for all eleven Upland varieties in going from IT1 to IT2, IT2 to IT3, IT3 to IT4, and IT4 to IT5 for November 2004 prices and low carrying costs is calculated at $320.07, $150.15, $100.54, and -$28.16 per acre-foot of water. If steeper mike discounts (November 1999), a lower base lint price (45¢/lb.), and higher costs (i.e., more costly insecticide and chemical costs) are imputed to extend the crop, the marginal value of an acre-foot of water for all Upland varieties and replications in going from IT1 to IT2, IT2 to IT3, IT3 to IT4, and IT4 to IT5 is estimated at $164.04, $48.15, $12.97, and -$94.79. Profitability and the value of water for extending the season varies quite markedly between different varieties and termination dates.
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Kamalha, Edwin. "Resources protection : towards replacement of cotton fiber with polyester." Thesis, Lille 1, 2019. http://www.theses.fr/2019LIL1I024/document.
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La demande annuelle de coton augmente en raison de la croissance démographique mondiale et de l’évolution des comportements d’achat des consommateurs. D'autres options de fibres naturelles telles que la laine, le lin et la soie, entre autres, sont produites dans des proportions très maigres. Le polyester (poly (téréphtalate d’éthylène) (PET) présente des qualités qui pourraient répondre à cette préoccupation pour les vêtements. Malheureusement, les consommateurs hésitent à porter des vêtements 100% polyester, principalement en raison d’un confort sensoriel inférieur, du toucher et parfois de leur apparence. Cette étude visait à améliorer le tissu en PET caractéristiques afin de réduire l'écart entre la perception humaine et la performance hydrophile du coton par rapport au PET Pour déterminer la disparité existant entre le coton et les tissus tissés en PET, une étude multisensorielle a été réalisée à l'aide d'un panel de 12 juges formés sur 11 descripteurs sensoriels. Des algorithmes de Monte Carlo, des algorithmes génétiques et la technique de Borda Count (BK) ont été utilisés pour la fusion de rangs .L'analyse en composantes principales (PCA) et la classification hiérarchique par agglomération (AHC) ont été utilisées pour créer des profils sensoriels. Tissus en PET et en coton (p = 0,05). Il a été déduit que l’aspect visuel et esthétique peut être utilisé pour distinguer le PET du tissus de coton. Pour remplacer le coton par du PET via cette approche sensorielle, la modification de la rigidité des tissus en polyester a été judicieusement réalisée à l'aide de NaOH et d'un adoucissant en silicium, avec une pré-oxydation au plasma atmosphérique. Les tissus en PET traités avec NaOH et l’adoucissant en silicone ont été perçus comme étant doux, lisses, moins nets et moins raides par rapport à certains tissus en coton et en PET non traité. Le profilage des tissus indique que les tissus en PET conventionnels peuvent être distingués des tissus en coton conventionnels en utilisant une évaluation à la fois subjective et objective. Il est également avancé que la perception sensorielle humaine sur textile ne peut être directement représentée par des mesures instrumentales. La dernière partie de l’étude compare le potentiel hydrophile et l’efficacité de deux monomères vinyliques: le poly- (éthylène glycol) diacrylate (PEGDA) et le chlorure de [2- (méthacryloyloxy) éthyl] triméthylammonium (METAC) radicalement photo-greffé sur la surface de Tissu en PET. Une étude de surface utilisant la spectroscopie photoélectronique à rayons X (XPS) et la spectroscopie à dispersion d'énergie (EDS) a confirmé le greffage. Les tests d'humidité indiquent que PEGDA et METAC induisent un mouillage complet du PET à des concentrations de 0,1 à 5% (V: V). Les mesures colorimétriques (K/S et CIELAB/CH) et la stabilité de la couleur sur les tissus teints en PET suggèrent que les deux monomères améliorent considérablement l'efficacité de la teinture du PET. Il est suggéré que PEGDA et METAC génèrent des groupes hydrophiles sur le PET; les macroradicaux sont sous la forme de structures vinyliques qui forment des greffes à chaîne courte et démontrent une fonction hydrophile. Les résultats de cette recherche peuvent jouer un rôle directeur pratique dans la conception des tissus, la conception des propriétés sensorielles et contribuer au développement de tissus en polyester de type cotonThere is increasing annual demand for cotton due to world population growth and changes in consumers’ purchasing behavior. Other natural fiber options such as wool, linen and silk among others, are produced in very meager proportions. Polyester (poly(ethylene terephthalate) (PET) has qualities that could address this concern for apparel. Unfortunately, consumers are reluctant to wear 100% polyester clothing mainly due to inferior sensory comfort, touch and sometimes appearance. This study sought to improve PET fabric characteristics in order to decrease the gap between human perception and hydrophilic performance of cotton vs. PET. To determine the disparity between cotton and PET woven fabrics, a multisensory study was undertaken using a panel of 12 trained judges against 11 sensory descriptors. Cross-entropy Monte Carlo algorithms, Genetic algorithms, and the Borda Count (BK) technique were used for rank fusion. Principle component analysis (PCA) and agglomerative hierarchical clustering (AHC) were used to create sensory profiles. The descriptor crisp accounted for the highest variability between PET and cotton fabrics (p˂0.05). It was deduced that visual and aesthetics can be used to distinguish between PET and cotton fabrics. To replace cotton with PET via this sensory approach, the modification of stiffness of polyester fabrics was judiciously carried out using NaOH and a silicon softener, with atmospheric air plasma pre-oxidation. PET fabrics treated with NaOH and the silicon softener were perceived soft, smooth, less crisp, and less stiff compared to some cotton and untreated PET fabrics. The profiling of fabrics indicates that conventional PET fabrics can be distinguished from conventional cotton fabrics using both subjective and objective evaluation. It is also argued that textile human sensory perception cannot be directly represented by instrumental measurements. The final part of the study compares the hydrophilic potential and efficacy of two vinyl monomers: Poly-(ethylene glycol) diacrylate (PEGDA) and [2-(methacryloyloxy) ethyl]-trimethylammonium chloride (METAC) radically photo-grafted on the surface of PET fabric. Surface study using X-ray photoelectron spectroscopy (XPS) and Energy Dispersive Spectroscopy (EDS) confirmed the grafting. Moisture tests indicate that PEGDA and METAC induce complete wetting of PET at concentrations 0.1-5% (V:V). Colorimetric measurements (K/S and CIELAB/CH) and colorfastness on dyed PET fabrics suggest that both monomers greatly improve the dyeing efficiency of PET. It is suggested that PEGDA and METAC generate hydrophilic groups on PET; the macroradicals are in a form of vinyl structures which form short chain grafts and demonstrate hydrophilic function. The results of this research can play a practical guiding role in the design of fabrics, sensory property design and contribute to the development of cotton-like polyester fabrics
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Rumney, C. J. "An in vitro study of the metabolic activities of bacteria from the human colon." Thesis, Open University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234270.
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BOURIE, CHRISTINE. "Contribution a l'etude des systemes de delivrance des principes actifs au niveau du colon." Clermont-Ferrand 1, 1998. http://www.theses.fr/1998CLF1PP02.
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Meyer, Seth Dominic. "A model of textile fiber supply and inter-fiber competition with emphasis on the United States of America /." free to MU campus, to others for purchase, 2002. http://wwwlib.umi.com/cr/mo/fullcit?p3060124.
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Gourlot, Jean-Paul. "Effets des caractéristiques de fibres de coton sur la mesure de leur résistance de rupture." Mulhouse, 2002. http://www.theses.fr/2002MULH0697.
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Les fibres de coton occupent la première place des fibres textiles avec 20 millions de tonnes transformées annuellement. Leur prix de vente est fixé en relation avec leur qualité : celle-ci est évaluée traditionnellement ou par des techniques instrumentales comme les appareils de mesure High Volume Instrument qui connaissent un fort développement. Ils permettent la caractérisation d'une dizaine de critères technologiques, reflets des propriétés intrinsèques des fibres de coton. Afin de fixer les règles de vente à la qualité, les professionnels ont normalisé les méthodes de mesures instrumentales des principaux paramètres. Des méthodes de mesures absolues et fondées sur des grandeurs physiques quantifiables sont dorénavant recherchées pour créer un référentiel absolu pour l'étalonnage des appareils HVI. L'objectif de cette thèse est d'analyser les biais des mesures de ténacité (résistance spécifique des forces de rupture sur masse linéique) réalisées sur HVI, liés aux autres propriétés des fibres, à leurs distributions statistiques et à leurs éventuelles interactions et combinaisons. Les résultats de ce travail original indiquent que les méthodes de mesures des caractéristiques étudiées occasionnent notamment une erreur d'estimation des masses de fibres rompues lors du test de dynamométrie. L'importance de ce biais est à relativiser par rapport aux niveaux des autres erreurs et de la précision globale des mesures. Sans améliorations matérielles conséquentes, les installations HVI ne pourront pas devenir la méthode de référence pour la mesure de la ténacité sur la base de grandeurs physiques mesurables. Sur le plan scientifique, la mesure des propriétés intrinsèques majeures sur chaque fibre serait requise pour la compréhension des phénomènes observés. Pour leur utilisation commerciale, les limites de confiance des résultats produits par les appareils HVI restent cependant acceptables
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Preuss, Mary Lai. "The roles of kinesin-related proteins in cotton fiber development /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2002. http://uclibs.org/PID/11984.
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Mejri, Mahdi. "Nouveaux textiles "intelligents" obtenus par greffage de microcapsules en polyamide sur fibres de coton." Mulhouse, 2005. http://www.theses.fr/2005MULH0823.
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Le but de cette thèse est la synthèse de micro-capsules en dispersion eau dans huile, microcapsules qui se fixent sur la cellulose par liaisons covalentes. Après la réalisation de la dispersion eau dans huile, les microcapsules sont produites par polycondensation interfaciale d'un polyamide. La formation du polymère est gérée par la cinétique de diffusion de la diamine de la phase aqueuse à la phase organique. La surface de ces microcapsules est alors modifiée : 1ere étape : on fixe à leur surface des fonctions amines 2eme étape : sur ces fonctions amines on ajoute alors des groupes susceptibles de réagir avec les -OH de la cellulose. Les microcapsules ainsi réalisées sont fixées sur le coton par liaison covalente et celles résistent au lavage ménager à 60°C.
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Mortazavi, Sayed Madjid. "Contribution à l'étude du virage de nuance de coton teint après le traitement infroissable." Mulhouse, 1993. http://www.theses.fr/1993MULH0286.
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Cortez, Joao Marques. "Biofinishing of cotton fabrics with genetically modified strains of Trichoderma reesei cellulases." Thesis, De Montfort University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.391644.
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Diaz, Galarraga Rodrigo Rogelio. "Impact of the red imported fire ant upon cotton arthropods." Thesis, [College Station, Tex. : Texas A&M University, 2003. http://hdl.handle.net/1969.1/254.
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Silvertooth, J. C., A. Galadima, E. R. Norton, and H. Moser. "Evaluation of Irrigation Termination Effects on Fiber Micronaire and Yield of Upland Cotton, 2000." College of Agriculture, University of Arizona (Tucson, AZ), 2001. http://hdl.handle.net/10150/211309.
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Arizona has experienced a trend toward increasing fiber micronaire values in recent years resulting in substantial discounts on fiber value. There is some evidence to suggest that irrigation termination management can impact fiber micronaire. A single field study was conducted in 2000 at the Maricopa Agricultural Center (1,175ft. elevation) to evaluate the effects of three dates of irrigation termination on the yield of 13 Upland cotton varieties. Planting date was 6 April (668 HU/Jan 1 86/55° F thresholds). Three dates of irrigation termination (IT1, IT2, and IT3) were imposed based upon crop development into cutout. The earliest irrigation termination date, IT1 (24 July) was made slightly ahead of an optimum date to provide sufficient soil-water such that bolls set at the end of the first fruiting cycle would not be water stressed and could be fully matured. Thus, the IT1 date was imposed to try to reduce overall micronaire. The second termination (IT2) date was 17 August, and provided one additional irrigation over an optimal point for the first cycle fruit set and two irrigations beyond IT1. The final (IT3) date was 15 September, which was staged so that soil moisture would be sufficient for the development of bolls set up through the last week of September thus providing full top-crop potential. Lint yield and micronaire results revealed significant differences among the IT treatments. Micronaire and lint yield values increased with later IT dates.
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Girardeau, Samuel. "Étude de réactions d'estérification et de transestérification de fibres, fils et tissus de coton à l'aide de réactifs gras, en vue de leur conférer un caractère hydrophobe." Toulouse, INPT, 2000. http://www.theses.fr/2000INPT016C.
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Le coton est la fibre textile végétale la plus utilisée mais elle est souvent remplacée par des fibres synthétiques pour des utilisations extérieures du fait de son caractère hydrophile. Nous avons ainsi développé des procédés d'hydrophobation de fibres cellulosiques (fibres, fils et tissus de coton en particulier) par des réactions d'acylation à l'aide de dérivés d'acides gras directement issus des huiles végétales. Puisque la structure cristalline de la cellulose conditionne la réactivité de ses groupements hydroxyles, nous avons utilisé deux types de prétraitement des fibres cellulosiques afin d'y faciliter la pénétration des réactifs gras : l'échange de solvants et, pour la première fois, l'émulsion. Dans un premier temps, nous avons réalisé l'estérification et la transestérification de la cellulose à l'aide respectivement de l'acide octanoi͏̈que et du laurate de méthyle dans un réacteur classique en utilisant un sel d'acide gras. Les esters cellulosiques obtenus après 6 heures de réaction à 195°C ont des degrés de substitution (DS) de 0,28 et 0,13 respectivement. Dans un deuxième temps, nous avons utilisé les micro-ondes comme nouvelles sources d'énergie pour réaliser ces deux réactions. Les esters obtenus ont des DS respectivement de 0,14 et 0,10 après seulement 5 minutes de réaction à 195°C. La diminution considérable de la durée de réaction s'accompagne d'une dégradation moindre des fibres cellulosiques. Ces techniques ont été ensuite généralisées à des réactifs gras de masse moléculaire plus importante entraînant une diminution du DS. Des analyses physiques et mécaniques nous ont permis d'expliquer l'influence du prétraitement, de la nature des réactifs et des conditions expérimentales sur les propriétés de fibres, fils et tissus de coton. Les méthodes d'acylation mises au point permettent ainsi de conférer aux substrats cellulosiques un caractère hydrophobe marqué.
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Roche, Meghan C. "A study of programmed cell death in cotton (gosypium hirsutum) fiber." Thesis, [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-1599.
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Kaewprasit, Chongrak. "Contribution a l'estimation de la surface specifique des fibres de coton : relations entre surface et proprietes physiques." Montpellier 2, 1997. http://www.theses.fr/1997MON20099.
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L'adsorption de l'azote en phase gazeuse et l'adsorption du bleu de methylene en phase aqueuse sont utilisees pour estimer la surface specifique des differents types de fibres de coton standard iccs. Le bleu de methylene s'est avere un adsorbat adequat pour la determination de la surface des fibres. Les differentes valeurs de la surface specifique sont interpretees en se fondant sur les caracteristiques physiques des fibres determinees au moyen de la diffraction de rx, et de l'analyse thermique. Nous avons note une influence du caractere cristallin et du contenu en eau de chaque fibre sur la valeur de la surface. De plus, une relation entre la surface specifique et la finesse d'une fibre est mise en evidence. Ce travail a permis d'eclaircir sur les facteurs intervenant dans la valeur de la surface specifique.
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Britz, Lizaan. "A comparison of the comfort properties, measured with a sweating manikin (WalterTM), of clothing containing different fibres." Thesis, Nelson Mandela Metropolitan University, 2017. http://hdl.handle.net/10948/14752.
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The main objective of the present study was to determine the relative role and importance of worsted suiting fabric fibre blend vis-à-vis fabric structural parameters, on the comfort related properties of 12 clothing ensembles, each comprising a different man’s suit, but the same wool/nylon underwear and cotton shirt. To achieve the objective, the comfort related properties, namely thermal resistance (Rt) and water vapour resistance (Ret) and water vapour permeability index (Im), of the clothing ensembles, as determined by means of WalterTM, a thermal sweating fabric manikin, were subjected to multi-linear and multi-quadratic analysis, as dependent variables, with the various suiting fabric parameters, namely weight, thickness, density, porosity, air permeability and wool content, as independent variables. It was found that the multi-quadratic regression analysis was able to best explain the observed differences in the clothing ensemble comfort related properties, in terms of the differences in suiting fabric properties. The regression analyses were used to isolate and quantify the effects of the various fabric and fibre content variables on the above mentioned comfort related properties of the various clothing ensembles. This study indicated that the suiting fabric structural properties (notably air permeability), had a more significant influence than either fibre blend or suiting fabric, as measured on WalterTM, a thermal sweating fabric manikin.
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Cui, Xiaojiang. "Identification of cotton fiber stage-specific genes and characterization of a potential plant callose synthase subunit CFL1 /." Digital version accessible at:, 1999. http://wwwlib.umi.com/cr/utexas/main.
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Regadas, Sthela Maria Murad. "Efeitos da suplementaÃÃo com fibra solÃvel ou frutooligossacarÃdeos sobre a inflamaÃÃo e o metabolismo no colo normal ou na vigÃncia de colite induzida por Ãcido trinitrobenzeno sulfÃnico, em ratos." Universidade Federal do CearÃ, 2004. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=301.
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CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel SuperiorO objetivo desse estudo foi verificar o efeito da suplementaÃÃo intragÃstrica com fibra solÃvel e prebiÃtico (frutooligossacarÃdeos - FOS), do ponto de vista inflamatÃrio e metabÃlico, no tecido cÃlico normal ou na vigÃncia da colite induzida por Ãcido trinitrobenzeno sulfÃnico (TNBS), em ratos. Foram usados 96 ratos da linhagem Wistar, machos, com peso mÃdio de 300g. Foram distribuÃdos aleatoriamente em dois grupos, com 48 animais. Um Grupo Estudo Sem Colite (GESC) submetido à aplicaÃÃo transanal de Ãgua ou outro Grupo Estudo Com Colite (GEC) induzida por TNBS, 20 mg mais etanol à 50%. Cada grupo foi redistribuÃdo em 3 subgrupos, de acordo com a substÃncia utilizada por infusÃo intragÃstrica: 1(Ãgua), 2(Fibra solÃvel) e 3(FOS). Todos os animais receberam essas soluÃÃes durante 14 dias antes da aplicaÃÃo transanal de Ãgua ou da induÃÃo da colite, atà o dia determinado para eutanÃsia (7 e 14 dias). Foram realizadas avaliaÃÃes do peso dos animais, relaÃÃo peso/tamanho do colo, escores macroscÃpicos e microscÃpicos, e dosagens de metabÃlitos no tecido cÃlico in vivo (concentraÃÃes de corpos cetÃnicos [3-hidroxibutirato, acetoacetato], piruvato, lactato, ATP e relaÃÃo [acetoacetato]/[3-hidroxibutirato] e [piruvato]/[lactato]. Foram avaliados o GESC, GEC, e os subgrupos Ãgua, do grupo sem colite (ESC1) e com colite (EC1). NÃo houve alteraÃÃes significantes nos diversos parÃmetros inflamatÃrios avaliados no GESC. No GEC, houve aumento na relaÃÃo peso do colo/comprimento do colo no subgrupo FOS, no 14 dia (ρ<0,05). Com relaÃÃo ao peso dos animais, os do subgrupo GEC1, apresentaram reduÃÃo significante no 7 dia. Houve aumento na relaÃÃo peso/tamanho do colo, no escores macro e microscÃpico no subgrupo GEC1 no 7 e 14 dias (ρ<0,05). Quanto à avaliaÃÃo metabÃlica, no GESC foi evidenciado aumento nas concentraÃÃes de acetoacetato no subgrupo fibra solÃvel no 14 dia (ρ<0,05). Houve reduÃÃo nas concentraÃÃes de piruvato no subgrupo fibra solÃvel e FOS no 14 dia (ρ<0,05). As concentraÃÃes de ATP foram reduzidas nos subgrupos fibra solÃvel e FOS, no 7 e 14 dias (ρ<0,05). No GEC, as concentraÃÃes do piruvato apresentaram-se elevadas no subgrupo fibra solÃvel, no 14 dia (ρ<0,05). As concentraÃÃes de ATP diminuÃram nos subgrupos fibra solÃvel e FOS (ρ<0,05). Comparando os subgrupos GESC1 com GEC1, houve elevaÃÃo nas concentraÃÃes dos corpos cetÃnicos no GEC1 no 7 dia (ρ<0,05). Houve reduÃÃo nos nÃveis de piruvato no GEC1 no 7 e 14 dias (ρ<0,05). Observou-se reduÃÃo nas relaÃÃes [acetoacetato]/[3-hidroxibutirato] e [piruvato]/[lactato] no GEC1, no 7 dia (ρ<0,05). Conclui-se, portanto, que a suplementaÃÃo intragÃstrica com fibra solÃvel ou com FOS, nÃo alteram os parÃmetros inflamatÃrios avaliados no 7 e 14 dias, nos colos normais ou na vigÃncia de colite, porÃm eleva a oferta de precursores para produÃÃo de energia, alterando as concentraÃÃes in vivo de ATP, tanto no tecido cÃlico normal, como na vigÃncia da colite.
The aim of this study was research the metabolic and inflammatory findings in normal colon and trinitrobenzene sulphonic acid-induced (TNBS) colitic rats which received soluble fiber and fructooligosaccharides-FOS. Ninety six Wistar male rats were used, average weight 300g. They were distributed in two groups, of 48 animals each. One group with animals without colitis (GESC) submitted to transanal water enema and another group with colitis (GEC) produced by TNBS, 20mg. Each group was distributed into three subgroups, according to the used substance: 1(water), 2(soluble fiber), 3(FOS). All the animals received 3 ml such substances twice daily into the stomach through an intragastric catether during 14 days before the transanal water enema and the colitis production until the euthanasia day (7th and 14th. Days). The animals were evaluated concerning to the weight, colon weight/size relationship, macroscopic and microscopic scores and the metabolites colon in vivo concentrations (ketone bodies [3-hydroxybutirate, acetoacetate], piruvate, lactate and ATP). The cell redox estate was also evaluated by the [acetoacetate]/[3-hydroxybutirate] and [piruvate]/[lactate] relationship. GESC and GEC were evaluated, equally the subgroups water from the group without colitis (ESC1) comparing to the colitis group (EC1). No significant differences were found in the various inflammatory evaluated parameters in GESC group. An increased colon weight/size relationship was found in GEC group in the subgroup FOS, on the 14th day (p<0,05). Concerning to the animals weight from the subgroup GEC1, a significant decreasing was found on the 7th day. An increased colon weight/size relationship was found in macroscopic and microscopic scores in the subgroup GEC1 on the 7th and 14th days (p<0,05). Concerning to the metabolic evaluation, an increased acetoacetate concentration was found in GESC, in the fiber subgroup on the 14th day (p<0,05). Decreased piruvate concentrations in the fiber and FOS subgroups were demonstrated on the 14th day (p<0,05). The ATP concentrations were reduced in the fiber and FOS subgroups on the 7th and 14th days (p<0,05). The piruvate concentrations were increased in GEC group, in the fiber subgroup, on the 14th day (p<0,05). The ATP concentrations decreased in the fiber and FOS subgroups (p<0,05). Comparing the subgroups GESC1 with GEC1, an increased cetonic corps concentration was found in GEC1 on the 7th and 14th days (p<0,05). There was reduction of piruvate levels in GEC1 on the 7th and 14th days (p<0,05). There was also reduction in acetoacetate/3-hidroxibutirate and piruvate/lactate relationship in GEC1, on the 7th day (p<0,05). Itâs concluded that the soluble fiber or FOS intragastric intake doesnât change the evaluated inflammatory parameters on the 7th and 14th days in normal colons or during colitis process, but it increases the precursors offering for energy production, modifying the ATP in vivo concentrations in normal colonic tissue and during colitis process.
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Bhouri, Naoufel. "Comportement thermodynamique et dimensionnel des matériaux textiles soumis à des variations des conditions climatiques." Thesis, Nancy 1, 2009. http://www.theses.fr/2009NAN10120/document.
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Ce travail constitue une contribution à l'étude de l'influence de la déformation libre des fibres textiles sous l'effet des contraintes hydriques sur la structure globale d'un tricot Jersey et d'un tissu Toile en coton, ayant subi les mêmes traitements de finition. Une comparaison entre les capacités de sorption du Jersey et des fils défilés de leur structure montre que le serrage géométrique limite les capacités de sorption du Jersey. Les coefficients du tenseur déformation plane du Jersey sous l'effet d'un cycle d'adsorption/désorption montre un gonflement croissant en fonction de l'humidité au moment de l'adsorption et un rétrécissement presque linéaire au moment de la désorption pour reprendre ses valeurs initiales marquant ainsi l'effet mémoire de l'état relaxé de la structure. L'influence du repassage sur le comportement de la Toile en coton sous l'effet de deux cycles continus successifs d'adsorption/désorption est étudiée. Les résultats montrent que l'aplatissement des fils dans la structure génère une amplification de la déformation plane résultante. Un deuxième cycle d'adsorption successif montre l'annulation complète de l'effet de repassage. Une comparaison entre les isothermes d'adsorption et de désorption d'un tissu Toile repassé et non repassé montre que les isothermes de sorption de la Toile repassée et non repassée se collent dés la troisième zone de l'isotherme du premier cycle d'adsorption, ce qui explique que l'encombrement stérique des molécules d'eau dans la structure de la Toile repassée génère un réarrangement stéréochimique de la structure supramoléculaire pour reprendre une forme similaire à la Toile non repasséeThe 2D deformation of bleached plain weave and Jersey cotton ready to wear clothing was measured during adsorption and desorption cycles. The strain along warp and weft directions and the shear deformation were evaluated by image correlation process. The dimensional variations are explained by geometrical consideration of the structure at microscopic (fibers scale) and macroscopic levels (yarns scale). Indeed, the reaction between water vapor molecules and material enlightens two steps. At first, the swelling fibers fill the micro pores inside the yarns. Then, the yarns swell and push on their neighbors to fill up the macro pores and cause the macroscopic swelling of the overall structure. During the desorption phase, the fibers shrink to create a free space inside the plain weave structure that will be relaxed to find its initial state. The shear deformation is related to the cohesion by twist between cotton fibers. The ironing generates flattened yarns and increases their friction which amplifies the deformation during the first adsorption cycle. However, this effect is cancelled at the end of the first adsorption / desorption cycle with no memory effect of the ironing process. These results are confirmed by comparison between sorption isotherms of ironed and not ironed plain weave samples. A comparison between the sorption capacity of Jersey and yarn made of the same structure shows that the geometric form decreases the sorption capacity of jersey especially at high humidity. Then knitting infects the swelling of yarns and decreases their sorption capacity
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Ge, Yufeng. "Mapping in-field cotton fiber quality and relating it to soil moisture." Thesis, [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-1425.
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LIMA, Anny Kelly Vasconcelos de Oliveira. "Comportamento das principais características tecnológicas da fibra do algodão BRS 200 Marrom, armazenada em duas microrregiões Paraibanas." Universidade Federal de Campina Grande, 2007. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/960.
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O mercado do algodão colorido vem crescendo no Brasil,onde no estado da Paraíba está sendo produzido em escala comercial com participação de pequenos produtores, os quais vêm recebendo em media de 30 a 40% a mais por quilo desse algodão em relação à fibra de cor branca. A cadeia produtiva do mesmo já é uma marca do estado, contando com várias indústrias de confecções capitaneadas pela "Natural Fashion" e com mercado garantido para a Europa e outras regiões do mundo. Sabendo-se que o armazenamento objetivando a conservação da fibra com qualidade é de grande importância em sua cadeia produtiva, principalmente para as indústrias, com características tecnológicas que forneça ao consumidor final um produto confortável, o presente trabalho foi desenvolvido para avaliar os efeitos do armazenamento sobre as características tecnológicas (comprimento, uniformidade, índice de fibras curtas, maturidade, micronaire, alongamento, resistência, reflectância e grau de amarelamento) do algodão BRS 200 Marrom, em dois municípios paraibanos (Campina Grande e Patos) durante 27 meses (0, 3, 6, 9, 12, 15, 18, 21, 24 e 27). Após a caracterização das fibras, estas passaram por um processo de enfardamento e foram distribuídas para o armazenamento nos dois locais. O delineamento estatístico utilizado foi o inteiramente casualísado, em esquema fatorial 2 x 10 + 5 , para os fatores local e tempo de armazenamento. Empregou-se o teste de Tukey para a comparação de médias, e, mediante os resultados, concluiu-se que o tempo e o local de armazenamento influem nas características da fibra do algodão BRS 200 Marrom; ao longo do tempo de armazenamento o grau de amarelamento tende a aumentar e o grau de reflexão a diminuir. O algodão armazenado em Patos manteve melhor qualidade da fibra quanto ao +b, reflectância, índice de fibras curtas e maturidade e em Campina Grande ao micronaire, alongamento e resistência; para as característica comprimento comercial houve igualdade estatística para os dois locais de armazenamento; o micronaire tende a aumentar, à medida que aumentou o tempo de armazenamento. Não foi possível uma classificação de tipo do algodão, pois ainda não existem padrões de classificação do algodão colorido, sendo necessária uma adaptação do diagrama de Hunter's para a obtenção desses valores.
The market of the cotton colorful comes growing in Brazil,where in the state of the Paraíba he is being produced in commercial scale with participation of small producers, which comes on average receiving from 30 40% more for kilo of this cotton in relation to the fíber of white color. The productive chain of the same already is a mark of the state, counting on some industries of confections commanded for the "Natural Fashion" and on market guaranteed for the Europe and other regions of the world. Knowing itself that the storage objectifying the conservation of the fíber with quality is of great importance in its productive chain, mainly for the industries, with technological characteristics that a comfortable product supplies to the final consumer, the present work was developed to evaluate the effect of the storage on the technological characteristics (length, uniformity, short staple fíbre index, maturity, micronaire, allonge, resistance, reflectance and degree of yellowing) of cotton BRS 200 Brown, in two paraibanos cities (Campina Grande and Patos) during 27 months (0, 3, 6, 9, 12, 15, 18, 21, 24 e 27).After the characterization of staple fibres, these had passed for a packing up process and had been distribuídas for the storage in the two places. The used statistical delineation was entirely casualisado, in factorial project 2 x 10 + 5 repetitions, for the factors local and time of storage the significant averages of the factors had been compared by the test of Tukey and by means of the results it concludes that: the time and the Place of storage influence in the characteristics of the fíber of cotton BRS 200 Brown; throughout the storage time +b tends to increase and the reflection degree to diminish; the cotton stored in Patos kept quality of the fíber better how much to +b, reflectance, index of short staple fibres and maturity and in Campina Grande to micronaire and allonge; for the characteristics resistance and commercial length it had equality statistics for the two places of storage; micronaire tends to increase, that is the fíber fhickened the measure that increased the storage time; a classification of type of the cotton was not possible, therefore not yet it exists standards of classification of the cotton colored, being necessary an adaptation of the diagram of Hunter for the attainment of these values.
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Silvertooth, J. C., and A. Galadima. "Late Season Crop Management Effects on Fiber Micronaire." College of Agriculture, University of Arizona (Tucson, AZ), 2003. http://hdl.handle.net/10150/197730.
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A field experiment was conducted during the 2002 growing season to evaluate a central Arizona grower’s method of addressing cotton fiber micronaire based on the management and timing of his agronomic inputs. The success of his inseason management, irrigation termination decision combined with his method of defoliation has led to a consistent production of premium fiber micronaire in recent years. Steps to accomplish crop defoliation and the subsequent mixing of seed cotton from the top (younger) and lower (older) bolls achieved at harvest are intended to keep the micronaire at premium levels and further prevent discounts on the crop. A companion study was conducted at the University of Arizona Maricopa Agricultural Center (MAC-1,175 ft. elevation) in an effort to duplicate the grower’s late season crop management operations. This study consisted of two treatments, a control (conventional) which received an application of 10 oz. Ginstar combined with ½ pt. surfactant in 20 gal./acre carrier and a treatment which received the conventional treatment in addition to a pre-defoliation Accelerate and a post-defoliation Gramoxone applications consistent with the grower’s methods. Plant growth and development measurements taken inseason revealed that height to node ratio (HNR) and fruit retention (FR) levels estimates were similar for both sites (grower fields and MAC study). Lint yield estimates indicated no difference between the conventional defoliation and the treatment receiving additional compounds at MAC. Results of the analyses performed on final micronaire data also indicated no significant difference in micronaire values between the two methods of defoliation and late season management at MAC. Fiber micronaire values exceeded the premium level (>5.0) for both treatments at MAC. However, results obtained from the cooperator-grower gin records revealed that average fiber micronaire for all of the fields monitored in this project were at premium level (<5.0).
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Silvertooth, J. C., and A. Galadima. "Late Season Crop Management Effect on Fiber Micronaire." College of Agriculture, University of Arizona (Tucson, AZ), 2004. http://hdl.handle.net/10150/198124.
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A field experiment was conducted during the 2002 and 2003 growing seasons to evaluate a central Arizona grower’s method of addressing high cotton fiber micronaire based on the management and timing of agronomic inputs. In-season management and irrigation termination combined with defoliation methods has led to consistent production of premium fiber micronaire in recent years. Steps to accomplish crop defoliation and the subsequent mixing of seed cotton from the top (younger) and lower (older) bolls achieved at harvest are intended to keep the micronaire at premium levels and further prevent discounts on the crop. A companion study was conducted in 2002 at the University of Arizona Maricopa Agricultural Center (MAC-1,175 ft. elevation) in an effort to duplicate the grower’s late season crop management operations. This study consisted of two treatments, a control (conventional) which received an application of 10 oz. Ginstar combined with 1/2 pt. surfactant in 20 gal./acre carrier and a treatment which received the conventional treatment in addition to a predefoliation of Accelerate and a post-defoliation of Gramoxone, consistent with the grower’s methods. At the grower’s location, data was collected during the 2002 and 2003 seasons. In 2002 and 2003, plant growth and development measurements taken in-season revealed that height to node ratio (HNR) and fruit retention (FR) levels tracked well and were similar for both sites and years (grower’s fields and MAC study). Lint yield estimates indicated no difference between conventional defoliation and the treatment receiving additional compounds at MAC in 2002. Average yield estimates were high for the cooperator-grower fields in both the 2002 and 2003 seasons. Results of the analysis performed on final micronaire data indicated no significant difference in micronaire values between the two methods of defoliation and late season management at MAC. In addition, fiber micronaire values exceeded the premium level (>5.0) for both treatments at MAC. In contrast, the data of 2002 and 2003 obtained from the cooperator-grower gin records revealed consistent results for average fiber micronaire for all of the fields monitored in this project which were at premium levels (<5.0).
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Clay, P. A., K. M. Young, and E. R. Taylor. "Effect of Heat Unit Accumulation on Cotton Defoliation, Lint Yield and Fiber Quality." College of Agriculture, University of Arizona (Tucson, AZ), 2006. http://hdl.handle.net/10150/198201.
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This study evaluated the effectiveness of defoliating at various heat unit accumulations: 630HU, 730 HU, 830 HU, 930 HU, 1030 HU, 1130 HU and 1330 HU and impact on lint yield and fiber quality. American Upland cotton variety DP 449 BR was planted on 12 April 2005 at the University of Arizona Maricopa Agriculture Center in Maricopa, Arizona. The experimental design was a split plot with four replications of each of seven defoliation timings. Final irrigation occurred on 05 August 2005. When heat unit accumulation reached 630 HU (on 20 August 2005), 730 HU (on 01 September 2005), 830 HU (on 04 September 2005), 930 HU (on 08 September 2005), 1030 HU (on 12 September 2005), 1130 HU (on 19 September 2005) and 1330 HU (on 27 September 2005) using the 86/55 F model chemical defoliants were applied. A mixture of Def (tribufos) at 24 oz/A, Dropp (thidiazuron) at 0.2 lb/A and Prep (ethephon) at 24 oz/A was applied using a high clearance research sprayer. The earliest treatments (630 and 730 HU accumulated) had significantly fewer open bolls at defoliation than those that received later treatments. At harvest, this trend disappears: the latest application (at 1330 HU) had significantly fewer open bolls than any other timing. Seven days after defoliant application (7 DAT), highest levels of defoliation were observed in the following treatments in descending order: 830 HU, 630 HU, 1130 HU, 930 HU and 730 HU followed by 1030 HU and 1330 HU. At harvest, there were no significant differences among mean defoliation percentages with the exception of the 1330 HU timing, which was significantly less defoliated than any of the other timings. Highest lint yield and gin turnout were observed in the earliest defoliation timings, lowest in the later timings. No significant differences in micronaire, length or uniformity were observed between defoliation timings. Differences did occur in fiber strength which was highest in earlier timings and lowest in the last timing, but all were above the discount level.
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Lutseke, Nothando Sazikazi. "An investigation into the properties of cotton fibres as used in nonwoven fabrics." Thesis, Rhodes University, 1989. http://hdl.handle.net/10962/d1018241.
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The purpose of this investigation was to determine the properties that characterise cotton fibres in the various stages in the CPNF process as well as to determine which fibre characteristics a r e required to entangle the fibres to produce a successful CPNF . The criteria adopted in this work for a successful CPNF include: 1. the tensile strength of the fabrics 2. a well-defined pattern 3. absorbency and wicking The properties selected for investigation were 1. the cotton fibre surface (using SEM and DSC analyses) 2. the degree of degradation of the cotton fibre as a result of the CPNF process (using cellulose fluidity measurements) 3. the non-cellulosic content of the fibre (using IR, DSC, and Chemical analyses) 4. fibre friction 5. absorbency and wicking 6. tensile properties Analysis of the results indicates clearly what the fundamental properties of the cotton fibre must be for a successful cotton CPNF to be manufactured. The conclusions also indicate the necessary properties a man-made fibre must have to produce a successful CPNF.