Tesis sobre el tema "Fibre de cotton"
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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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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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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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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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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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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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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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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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Scapinello, Marco. "Studio di processi al plasma freddo a pressione atmosferica per il trattamento delle fibre tessili". Doctoral thesis, Università degli studi di Padova, 2012. http://hdl.handle.net/11577/3422496.
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The main goals of my thesis project were to study, characterize and optimize the interaction of different atmospheric plasmas with textile materials (wool and cotton), to determine the effects of such interactions on the treated materials and to correlate them with the specific experimental conditions used. This thesis deals with the application of non-thermal plasmas to textile fibers and materials to achieve desired effects and properties such as anti-shrinking, anti-felting, wetting and the activation for wet finishing.
The analysis of the plasma processed gas was performed by FT-IR and APCI mass spectrometry. The results of this characterization allow us to understand the chemical oxidation phenomena.
The plasma treatment on wool fibers produces wettability and anti-shrinking properties, this effects are due to the oxidation and to the roughness imparted to the treatment.
The plasma treatment on the cotton fibers increases the hydrophilicity for the formation of new polar species and radicals on the surface: two wet finishing were applied to test the effects of plasma pre-treatment.
Finally, using OES we succeeded in characterizing a few important systems related to the gas composition and the radiative active specie of plasma (including radicals, ions, atoms or excited molecules).
In conclusion, the results of the research carried out for my doctoral thesis show that non-thermal plasma holds great promise for the treatment of fabrics: it offers the advantage of doing away with costly and environmentally impacting wet processes while at the same time producing similar or even better results in the treated materials.Il mio progetto di tesi ha riguardato lo studio, la caratterizzazione e l’ottimizzazione delle interazioni di diversi plasmi atmosferici con il materiale tessile (in particolare lana e cotone), determinando gli effetti che tale interazione produce sul materiale trattato e correlandola alle specifiche condizioni utilizzate. Lo scopo fortemente applicativo era quello di ottenere particolari proprietà ed effetti come l’antirestringimento, la bagnabilità, l’attivazione per successivi finissaggi liquidi. La caratterizzazione del gas di processo mediante spettroscopia FTIR e spettrometria di massa APCI ha permesso di comprendere la chimica dei fenomeni di ossidazione alla base degli effetti del trattamento. Il trattamento sulla fibra di lana produce una forte bagnabilità ed effetti di anti-restringimento, correlabili all'ossidazione della superficie e all'aumentata rugosità. Il trattamento sulla fibra di cotone aumenta l'idrofilicità della fibra per la formazione di radicali e nuove specie polari sulla superficie: sono stati applicati due finissaggi liquidi per verificare gli effetti del pretrattamento al plasma. Infine utilizzando di una tecnica diagnostica come la spettroscopia ottica di emissione è stato possibile caratterizzare alcuni importanti sistemi di emissione dovuti alla presenza di specie eccitate di atomi, molecole, radicali e ioni presenti in un plasma atmosferico. I risultati della ricerca effettuata per il dottorato dimostrano che il plasma atmosferico non termico rappresenta una grande promessa per il trattamento dei tessuti: offre il vantaggio di sostituire o di migliorare i processi liquidi costosi e di forte impatto ambientale e al tempo stesso di ottenere risultati simili o anche migliori nei materiali trattati.
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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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Johansson, Ludvig. "On the Mechanical Recycling of Woven Fabrics : Improving the Reusable Fibre Yield of Mechanical Methods". Thesis, Uppsala universitet, Tillämpad materialvetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-414569.
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This master thesis studies the recycling prospects of textiles. The textile industry contributes negatively to the global environmentthrough the release of greenhouse gases and consumption of resources. In order to achieve a circular textile industry, textiles must be recyclable by both chemical and mechanical means. Here, the focus is on mechanical extraction of staple fibres, particularly cotton, for reentry into yarn production. Experiments show that used, but undamaged, cotton sateen and cotton twill responds differently to abrasion with stochastic surfaces. Previous studies on the conventional shredding processes have shown positive impact from lubricants on extracted fibre lengths, by reducing inter-fibre friction. In the present study on abrasion, variables such as alignment of the weave pattern, lubrication and load are shown to have little to no impact on extracted fibre length, but notable effects on overall fibre quality. These analyses are supported by manual length assessment, electron micrographs and tensile tests using load cells. Furthermore, simple tests and observations on structured diamond surfaces constructed through chemical vapor deposition are promising for mechanical fibre release directly from a woven fabric. Suggestions are made on continued research in this field.
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Maccow, Awilda. "A chemo-enzymatic approach to expand the chemical space of cellulose-derived materials : Application to eco-friendly dyeing of cellulosic fibers". Electronic Thesis or Diss., Toulouse, INSA, 2022. http://www.theses.fr/2022ISAT0054.
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L'extension de l'espace moléculaire chimique accessible à partir de la biomasse végétale par des méthodes douces et propres est un sujet d'actualité qui stimule la communauté scientifique afin de développer des produits biosourcés à faible impact environnemental et d'élargir le champ d'exploitation de la biomasse. La fonctionnalisation de la cellulose, le polysaccharide le plus abondant sur la planète, et/ou des cello-oligosaccharides telle que décrite dans cette thèse s'inscrit dans cette démarche. Notre objectif était de développer une méthode chimio-enzymatique impliquant l'action d'une laccase assistée par un médiateur pour oxyder des cello-oligosaccharides ou des fibres cellulosiques, suivie d'une amination réductrice pour greffer des composés aminés sur le matériau cellulosique. Dans ce but, nous avons d'abord démontré l'oxydation du cellobiose et du méthyl cellobiose en utilisant la laccase de Trametes versicolor et le TEMPO comme médiateur. Les conditions d'oxydation ont été optimisées avec le méthyl cellobiose et appliquées à un mélange de cello-oligosaccharides et au cellopentaose. En utilisant l'analyse LC/MS, nous avons montré qu'une large gamme de composés oxydés est obtenue et que la méthode est efficace pour produire des cello-oligosaccharides acides potentiellement intéressants pour les domaines biomédical et nutraceutique. Ensuite, nous avons montré que la réactivité du cellopentaose oxydé avec deux molécules aminées, la p-toluidine et la rhodamine 123 (un colorant aminé), permettait la liaison du composé aminé aux oligosaccharides. À l'aide des techniques LC/MS et MS/MS, nous avons mis en évidence la présence d'une liaison amine forte et covalente entre les colorants et le cellopentaose, élargissant ainsi l'espace chimique accessible par ce procédé hybride. Après avoir réalisé cette preuve de concept, nous avons tenté la teinture de fils de coton. Les fibres cellulosiques sont l'un des principaux matériaux textiles biosourcés et biodégradables. Cependant, le traitement chimique des textiles et notamment les méthodes chimiques utilisées pour fixer les colorants de manière covalente sont extrêmement polluants et nocifs pour la santé. Proposer des alternatives plus respectueuses de l'environnement est un défi mais d'un intérêt primordial pour une entreprise comme PILI, impliquée dans le projet de thèse, qui développe des colorants naturels en utilisant la biologie de synthèse. Ainsi, le potentiel du procédé hybride à deux étapes a été utilisé pour greffer avec succès la p-toluidine, la rhodamine 123 et le rouge acide 33 sur des fils de coton. La liaison covalente établie entre ces colorants et la fibre de coton a été prouvée pour la première fois. De plus, une bonne homogénéité et une bonne résistance au lavage ont été observées pour la teinture avec l'acid red 33, démontrant la robustesse et l'applicabilité de l'approche en situation réelle. Ces résultats originaux ont été brevetés. En testant d'autres colorants aminés, nous avons également montré que la solubilité, la réactivité et la structure du colorant aminé sont des paramètres importants à prendre en compte pour l'optimisation de la teinture, ce qui ouvre la voie à la synthèse à façon de nouveaux colorants aminés adaptés à ce procédé hybride prometteurThe extension of the chemical molecular space accessible from plant biomass by soft and clean methods is a timely topic that stimulates the scientific community in order to develop biobased products with low environmental impact and to widen the field of biomass exploitation. The functionalization of cellulose, the most abundant polysaccharide on the planet, and/or cello-oligosaccharides as described in this thesis is part of this approach. Our objective was to develop a chemo-enzymatic method involving the action of a mediator-assisted laccase to oxidize cello-oligosaccharides or cellulosic fibers, followed by reductive amination to graft amino compounds onto the cellulosic material. To this end, we first demonstrated the oxidation of cellobiose and methyl cellobiose using the laccase from Trametes versicolor and TEMPO as a mediator. Oxidation conditions were optimized with methyl cellobiose and applied to a cello-oligosaccharide mixture and cellopentaose. Using LC/MS analysis, we showed that a wide range of oxidized compounds is obtained and that the method is effective in producing acidic cello-oligosaccharides potentially of interest for the biomedical and nutraceutical fields. Then, we showed that the reactivity of oxidized cellopentaose with two aminated molecules, p-toluidine and rhodamine 123 (an aminated dye), allowed the binding of the amino compound to the oligosaccharides. Using LC/ MS and MS/MS techniques, we provided evidence for the presence of a strong, covalent amine bond between the dyes and cellopentaose, thus enlarging the chemical space accessible through this hybrid process. After completed this proof of concept, we attempted the dyeing of cotton threads. Cellulosic fibers are one of the main biosourced and biodegradable textile materials. However, chemical processing of textiles and especially the chemical methods used to covalently fix dyes are extremely polluting and harmful to health. Providing more eco-friendly alternatives is a challenge but of prime interest for a company like PILI, which was involved in the thesis project and is developing natural dyes using synthetic biology. Thus, the potential of the two-pot/two-step hybrid process was used to successfully graft p-Toluidine, rhodamine 123 and Acid Red 33 onto cotton thread. The covalent bond established between these dyes and the cotton fiber was proven for the first time. In addition, good homogeneity and wash-fastness were observed for acid Red 33 dyeing, demonstrating the robustness and applicability of the approach in real life. These original results have been patented. By testing other amino dyes, we also showed that the solubility, reactivity and structure of the aminated dye are important parameters to be addressed for dyeing optimization, which opens the way to the custom synthesis of new amino dyes suitable for this promising hybrid process
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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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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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Norberg, Blixt Olivia y Maya Lindgren. "En studie om regenererade cellulosafibrer som ett alternativ till bomull i trikåmaterial". Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-22026.
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Bomullsfibern har många fördelaktiga egenskaper som gör den allmänt omtyckt bland både konsumenter och producenter. Den vanligaste framställningen av fibern är konventionellt odlad bomull, men dessvärre har denna typ av framställningsprocess en negativ inverkan på miljön i form av hög kemikalieförbrukning och hög vattenanvändning. I samband med att bomullens negativa miljöpåverkan uppmärksammas, bidrar det till en ökad efterfrågan på miljövänliga fibrer med skonsammare processer. Denna studie har utifrån detta perspektiv undersökt, jämfört och testat förutsättningarna för att helt eller delvis ersätta bomull i trikåmaterial. De fibrer som har undersökts är de regenererade cellulosafibrerna Tencel, lyocell och modal. Dels har två hundraprocentiga material testats: Tencel A100 och lyocell, dels två fiberblandningar: bomull/modal och GOTS-bomull/Tencel LF. Samtliga material har bestått av rågarn med garntjocklek Ne 30/1 och stickats fram i en rundstickningsmaskin. Testerna som har utförts rör dimensionsstabilitet, spiralvridning, noppbildning, nötningshärdighet och slutligen draghållfasthet. För att säkerställa trovärdiga resultat har testerna genomförts upprepade gånger och därefter har ett medelvärde för varje material beräknats. De material som uppvisat bäst resultat avseende egenskaper och miljöpåverkan var Tencel A100 och lyocell, samt fiberblandningen GOTS-bomull/Tencel LF.The cotton fiber has many advantageous properties which make it widely popular among both consumers and producers. The most common production of the fiber is conventionally grown cotton. This type of manufacturing process has unfortunately a negative impact on the environment because of its high chemical consumption and high water use. Since the negative environmental impact regarding cotton has got more attention, it has contributed to an increased demand for more environmentally friendly fibers with more eco-friendly processes. From this perspective, this study has examined, compared and tested the conditions for completely or partially replacing cotton in knitted materials. The fibers that have been examined are the regenerated cellulose fibers Tencel, lyocell and modal. Tencel A100 and lyocell have been tested independently and two fiber blends consisting of cotton/modal and GOTS-certified cotton/Tencel LF have been knitted and tested in this study. All materials have consisted of raw yarn with yarn thickness of Ne 30/1 and has been knitted in a circular knitting machine. The tests that have been carried out is dimensional stability, twisting, pilling resistance, abrasion resistance and finally tensile strength. To ensure reliable results, the tests have been done repeatedly and then an average value for each material has been calculated. The materials that showed the best results in terms of properties and environmental impact were Tencel A100, lyocell and the fiber mixture GOTS-certified cotton/Tencel LF.
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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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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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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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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
22
Silvertooth, J. C., A. Galadima, E. R. Norton y 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.
23
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 y 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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KAMALHA, EDWIN. "Resources Protection: Towards Replacement of Cotton Fiber with Polyester". Doctoral thesis, Politecnico di Torino, 2019. http://hdl.handle.net/11583/2734473.
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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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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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Silvertooth, J. C., A. Galadima, E. R. Norton y 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.
Texto completoResumen
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.
30
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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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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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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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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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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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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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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OLSSON, VICTOR. "The Cotton Cost : What is it, Why is it and what Could it be". Thesis, Högskolan i Borås, Institutionen Textilhögskolan, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-17477.
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This paper studies the current cotton market situation. The situation is a recent vast increase in cotton fibre price, mainly due to tight supply and demand circumstances. Focus is on two issues; how the fibre price affect companies cost wise and the likely future development of the cotton market. The cotton market has been studied by hard facts and contemporary views from industry people and companies. Factors influencing the cotton market such as economical growth, population and substitute textile fibres are taken into consideration. Besides how companies themselves claim to respond to the cotton price increase cost calculations approximated by thumb rules of the industry are performed. The result is a higher cost, derived from higher cotton price, at the finish garment stage. The magnitude depend on if one sees it relative to retail price or manufacturing cost along with how the participant in the value chain react. The future cotton market is evaluated by what might effect cotton supply and cotton demand and how the market mechanism is likely to answer. Short term the high prices seem to lower the demand and along with a larger harvest next season prices should be lowered. Long term the price is suggested to remain high because of a larger grow in demand then supply.Program: Magisterutbildning i Applied Textile Management
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OLSSON, VICTOR. "The Cotton Cost : What is it, Why is it and what Could it be". Thesis, Högskolan i Borås, Institutionen Textilhögskolan, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-20677.
Texto completoResumen
This paper studies the current cotton market situation. The situation is a recent vast increase in cotton fibre price, mainly due to tight supply and demand circumstances. Focus is on two issues; how the fibre price affect companies cost wise and the likely future development of the cotton market. The cotton market has been studied by hard facts and contemporary views from industry people and companies. Factors influencing the cotton market such as economical growth, population and substitute textile fibres are taken into consideration. Besides how companies themselves claim to respond to the cotton price increase cost calculations approximated by thumb rules of the industry are performed. The result is a higher cost, derived from higher cotton price, at the finish garment stage. The magnitude depend on if one sees it relative to retail price or manufacturing cost along with how the participant in the value chain react. The future cotton market is evaluated by what might effect cotton supply and cotton demand and how the market mechanism is likely to answer. Short term the high prices seem to lower the demand and along with a larger harvest next season prices should be lowered. Long term the price is suggested to remain high because of a larger grow in demand then supply.Program: Applied Textile Management
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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
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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.
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Clay, P. A., K. M. Young y 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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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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ANNY KELLY VASCONCELOS DE OLIVEIRA LIMA - DISSERTAÇÃO PPGEA 2007..pdf: 5227384 bytes, checksum: 6ef5a19264b3548b863b84043e70a6e4 (MD5)Made available in DSpace on 2018-06-13T13:38:49Z (GMT). No. of bitstreams: 1 ANNY KELLY VASCONCELOS DE OLIVEIRA LIMA - DISSERTAÇÃO PPGEA 2007..pdf: 5227384 bytes, checksum: 6ef5a19264b3548b863b84043e70a6e4 (MD5) Previous issue date: 2007-02
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. y 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. y 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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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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An, Chuanfu. "SNP CHARACTERIZAITON AND GENETIC AND MOLECULAR ANALYSIS OF MUTANTS AFFECTING FIBER DEVELOPMENT IN COTTON". MSSTATE, 2008. http://sun.library.msstate.edu/ETD-db/theses/available/etd-03302008-191842/.
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Cotton (Gossypium spp.) is the worlds leading textile fiber crop, and an important source of oil and protein. Insufficient candidate gene derived-markers suitable for genetic mapping and limited information on genes that control economically important traits are the major impediments to the genetic improvement of Upland cotton (G. hirsutum L.). The objectives of this study were to develop a SNP marker discovery strategy in tetraploid cotton species, SNP characterization and marker development from fiber initiation and elongation related genes, chromosomal assignment of these genes by SNP marker-based deletion analysis or linkage mapping, and genetic and molecular analysis of mutants affecting cotton fiber development. Phylogenetic grouping and comparision to At- and Dt-genome putative ancestral diploid species of allotetraploid cotton facilitated differentiation between genome specific polymorphisms (GSPs) and marker-suitable locus-specific polymorphisms (LSPs). By employing this strategry, a total of 222 and 108 SNPs were identified and the average frequency of SNP was 2.35% and 1.30% in six EXPANSIN A genes and six MYB genes, respectively. Both gene families showed independent and incongruent evolution in the two subgenomes and a faster evolution rate in Dt-genome than that in At-genome. SNPs were concordantly mapped to different chromsomes, which confirmed their value as candidate gene marker and indicated the reliability of SNP discovery stragey. QTL mapping by two F2 populations developed from fiber mutants detected major QTL which explain 62.8-87.1% of the phenotypic variation for lint percentage or lint index in the vicinity of BNL3482-138 on chromosome 26. Single marker regression analyses indicated STV79-108, which was located to the long arm of chromosome 12 (the known location of N1 and perhaps n2 loci), also had significant association (R2 % value 15.4-30.6) with lint percentage, lint index, embryo protein percentage and micronaire. Additional QTL and significant markers associated with other seed and fiber traits were detected on different chromosomes. Inheritance analysis indicated that both genetic models N1N1n2n2 and n2n2li3lisub>3 could lead to the fiberless phenotype. The observation of fuzzless-short lint phenotype indicated fiber initiation and elongation were controlled by different mechanisms. The penetrance of Li2 gene expression was observed in this study.
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Kaimouz, Ahmad Wassim. "An investigation of the printing process for lyocell and cotton fibres using inkjet technology". Thesis, Heriot-Watt University, 2010. http://hdl.handle.net/10399/2366.
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Sample preparation has been described as the weak link in microfluidics. In particular, plasma has to be extracted from whole blood for many analysis including protein analysis, cell-free DNA detection for prenatal diagnosis and transplant monitoring. The lack of suitable devices to perform the separation at the microscale means that Lab On Chip (LOC) modules cannot be fully operated without sample preparation in a full-scale laboratory. In order to address this issue, blood flow in microchannels has been studied, and red blood cells behaviours in different geometrical environments have been classified. Several designs have been subsequently proposed to exploit some natural properties of blood flow and extract pure plasma without disturbing the cells. Furthermore, a high-level modelling method was developed to predict the behaviour of passive microfluidic networks. Additionally, the technique proposed provides useful guidance over the use of systems in more complex external environments. Experimental results have shown that plasma could be separated from undiluted whole blood in 10μm width microchannels at a flow rate of 2mL/hr. Using slightly larger structures (20μm) suitable for mass-manufacturing, diluted blood can be separated with 100% purity efficiency at high flow rate. An extensive biological validation of the extracted plasma was carried out to demonstrate its quality. To this effect Polymerase Chain Reaction (PCR) was performed to amplify targeted human genomic sequence from cell-free DNA present in the plasma. Furthermore, the influence of the sample dilution and separation efficiency on the amplification was characterised. It was shown that the sample dilution does have an influence on the amplification of house-keeping gene, but that amplification can be achieved even on high diluted samples. Additionally amplification can also be obtained on plasma samples with a range of separation efficiencies from 100% to 84%. In particular, two main points have been demonstrated (i) the extraction of plasma using combination of constrictions and bifurcations, (ii) the biological validation of the extracted plasma.
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Gallo, Jenny M. "Elemental analysis of cotton fiber evidence for use in the field of forensic science". FIU Digital Commons, 2009. http://digitalcommons.fiu.edu/etd/3440.
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The purpose of this research is to introduce a method for the forensic elemental analysis of cotton fibers for the purpose of increasing the discrimination between otherwise similar cotton evidence using microwave digestion Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) and Laser Ablation- Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS). A quadrupole ICP-MS and UV laser ablation (266nm) instruments were used for the analysis. A cotton standard reference material (IAEA V-9) was used to validate the developed methods producing good accuracy with typically 10 % bias and good precision (typically 5% RSD) for the element list: 25Mg, 27Al, 55Mn, 57Fe, 88Sr and 137Ba. It was found that the LA-ICP-MS method resulted in improved precision over the solution ICP-MS method. Twenty four (24) raw cotton samples and five white cotton T-Shirts were analyzed with the developed methods. It was also found that all the raw cotton samples from different sources were distinguishable from each other, as were all the cotton T-shirts resulting in zero type I errors and zero type II errors for the pairwise comparisons.
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Silvertooth, J. C., A. Galadima y R. Tronstad. "Evaluation of Irrigation Termination Effects on Yield and Fiber Quality of Upland Cotton, 2004". College of Agriculture, University of Arizona (Tucson, AZ), 2005. http://hdl.handle.net/10150/198169.
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A field experiment was conducted in 2004 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 several Upland cotton varieties. In addition, the economic relationships of IT treatments were also evaluated. The first IT treatment (IT1) was made with the intention of terminating irrigations somewhat pre-maturely. 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). In this experiment, IT2 was structured to provide an additional (one) irrigation before the more optimal date. For the IT3 plots, the intention was to attempt to time termination to match the conventional growers optimal date. The IT4 and IT5 were imposed to attempt to produce a second cycle fruit set and irrigations continued until 27 August and 21 September respectively. In general, lint yield and micronaire results revealed significant differences among the IT treatments. In a similar fashion to 2000-2002 IT experiments, micronaire and lint yield values consistently increased with later IT dates. The best micronaire and lint yield results were achieved with IT4 date, which received 12 in. less irrigation water than IT5. The 12 in. water saved equates to approximately 20% of the total water used under the conventional practice. The average marginal value of water for all Upland varieties in going from IT1 to IT2, IT2 to IT3, IT3 to IT4, and IT4 to IT5 using 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 marginal value of water sometimes vary quite markedly between different varieties and termination dates as well.
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Silvertooth, J. C., A. Galadima y R. Tronstad. "Evaluation of Crop Management Effects on Fiber Micronaire, 2000-2001". College of Agriculture, University of Arizona (Tucson, AZ), 2002. http://hdl.handle.net/10150/197455.
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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 influence fiber micronaire. Approximately 400 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 and 2001 seasons. 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 approached cutout and the lower bolls began to open, open boll samples were then 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 sample micronaire, irrigation termination (IT), defoliation, and final crop micronaire were analyzed. Results indicate strong relationships with final fiber micronaire for factors such as total heat units (HU) accumulated by the crop from planting to IT, variety, region of production (environment), and green boll load at cutout. Results showed that as total HU accumulated from planting to IT exceeded approximately 2950 HU, micronaire levels significantly increased.