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.

Muitos dos locais onde as atividades são realizadas nas academias de ginásticas são salas pequenas e fechadas com sistema de climatização artificial, freqüentados por um grande número de alunos realizando seus exercícios e profissionais auxiliando as atividades. Com isso, há uma intensa transpiração desses indivíduos, uma freqüente rotina de limpeza do piso e de equipamentos com pequenos intervalos, possibilitando a alterações da qualidade do ar indoor. O presente trabalho busca mostrar as tendências de variações nos valores das concentrações dos poluentes atmosféricos BTEX em ambiente indoor, especificamente na sala de spinning de uma academia de ginástica do Rio de Janeiro. Para o monitoramento da qualidade do ar foram utilizados cartuchos de carvão ativado SKC, acoplado a uma bomba KNF com vazão de 1l min. Para a extração de cada amostra foi feita a análise cromatográfica com cromatógrafo a gás modelo 6890 acoplado a um espectrômetro de massa modelo 5973 da marca Agilent. Foram analisadas 34 amostras coletadas na salas de spinning durante as aulas com atividades aeróbicas, o que intensificava a respiração dos indivíduos, possibilitando uma maior inalação destes COVs. Em contrapartida, também foram coletadas 5 amostras outdoor, 4 delas pareadas indoor/ outdoor para uma análise comparativa das concentrações destes poluentes. Dentre os compostos orgânicos voláteis analisados, o tolueno é o BTEX mais abundante obtido neste trabalho, representando 81% destes COVs indoor. Todas as amostras medidas em pares indoor/ outdoor tiveram concentrações maiores no interior, exceto para o benzeno no dia 3/12/2010. Simples atividades usualmente realizadas pelo homem, como a inserção de piso emborrachado, manutenção do sistema de climatização artificial, e limpeza podem alterar o ar indoor. As conclusões alcançadas após as medições das concentrações de BTEX foram de que o ar indoor estava mais poluído do que o outdoor. Este monitoramento da qualidade do ar indoor ainda é escasso no Brasil. Alguns esforços tem sido feito em relação a ambientes confinados como a Portaria n˚3523 do Ministério da Saúde, regulamentando o controle dos ambientes climatizados e a Resolução n˚9 da Agência Nacional de Vigilância Sanitária, além da Resolução CONAMA n ˚3 estabelecendo padrões de qualidade do ar para alguns compostos químicos, porém muitos compostos químicos ainda não são legislados ou não possuem a devida atenção, não sendo suficientes para contemplar a complexidade do assunto / In many gyms work-out activities take place in small enclosed rooms where the climate is controlled artificially. Normally, those rooms are full of students doing their workout and trainers helping them. Intense human transpiration requires a frequent floor and equipment cleaning routine. This routine, performed at short intervals can affect the indoor air quality. This study is aimed at showing varying concentration levels of the BTEX air pollutant at a gym in Rio de Janeiro, Brazil, specifically the spinning room. To monitor the air quality, activated charcoal cartridges (SKC) were used, coupled to a KNF pump with a flow rate of 1l min. For the extraction of each sample, a gas chromatographic analysis machine model 6890 was used coupled to an Agilent mass spectrometer model 5973. We analyzed a total of 34 air samples collected in the spinning room during active aerobic classes; the increased respiration from the subjects allow for a greater inhalation of VOCs. In Contrast, five samples were also collected outdoors; four of them were paired indoor / outdoor for comparative analysis of these pollutants. Among the volatile organic compounds analyzed, toluene was the most abundant BTEX found in this study, representing 81% of indoor VOCs. In all the indoor / outdoor paired samples, the concentration was higher in the interior samples, with one exception, benzene on 3/12/2010. Simple changes that can easily be done by man, such as the installation of rubberized flooring, regular maintenance of the air acclimatization equipment, and general cleanliness can greatly affect the indoor air quality. The conclusion achieved after looking at the BTEX measurements was that the indoor air was more polluted than the air outdoors. This air quality monitoring is still scarce in Brazil. Some efforts have been made in relation to confined spaces such as Ordinance n˚ 3523 from the Ministry of Health, which regulates the air of air-conditioned environments and Resolution n˚ 9 of the National Agency for Sanitary Vigilance, as well as Resolution CONAMA n˚ 3 by setting standards for air quality for some chemical compounds, unfortunately many chemical compounds are not yet legislated or receive proper attention in this matter, therefore not giving this indoor air pollution matter enough grounds to address the complexity of the subject

Muitos dos locais onde as atividades são realizadas nas academias de ginásticas são salas pequenas e fechadas com sistema de climatização artificial, freqüentados por um grande número de alunos realizando seus exercícios e profissionais auxiliando as atividades. Com isso, há uma intensa transpiração desses indivíduos, uma freqüente rotina de limpeza do piso e de equipamentos com pequenos intervalos, possibilitando a alterações da qualidade do ar indoor. O presente trabalho busca mostrar as tendências de variações nos valores das concentrações dos poluentes atmosféricos BTEX em ambiente indoor, especificamente na sala de spinning de uma academia de ginástica do Rio de Janeiro. Para o monitoramento da qualidade do ar foram utilizados cartuchos de carvão ativado SKC, acoplado a uma bomba KNF com vazão de 1l min. Para a extração de cada amostra foi feita a análise cromatográfica com cromatógrafo a gás modelo 6890 acoplado a um espectrômetro de massa modelo 5973 da marca Agilent. Foram analisadas 34 amostras coletadas na salas de spinning durante as aulas com atividades aeróbicas, o que intensificava a respiração dos indivíduos, possibilitando uma maior inalação destes COVs. Em contrapartida, também foram coletadas 5 amostras outdoor, 4 delas pareadas indoor/ outdoor para uma análise comparativa das concentrações destes poluentes. Dentre os compostos orgânicos voláteis analisados, o tolueno é o BTEX mais abundante obtido neste trabalho, representando 81% destes COVs indoor. Todas as amostras medidas em pares indoor/ outdoor tiveram concentrações maiores no interior, exceto para o benzeno no dia 3/12/2010. Simples atividades usualmente realizadas pelo homem, como a inserção de piso emborrachado, manutenção do sistema de climatização artificial, e limpeza podem alterar o ar indoor. As conclusões alcançadas após as medições das concentrações de BTEX foram de que o ar indoor estava mais poluído do que o outdoor. Este monitoramento da qualidade do ar indoor ainda é escasso no Brasil. Alguns esforços tem sido feito em relação a ambientes confinados como a Portaria n˚3523 do Ministério da Saúde, regulamentando o controle dos ambientes climatizados e a Resolução n˚9 da Agência Nacional de Vigilância Sanitária, além da Resolução CONAMA n ˚3 estabelecendo padrões de qualidade do ar para alguns compostos químicos, porém muitos compostos químicos ainda não são legislados ou não possuem a devida atenção, não sendo suficientes para contemplar a complexidade do assunto / In many gyms work-out activities take place in small enclosed rooms where the climate is controlled artificially. Normally, those rooms are full of students doing their workout and trainers helping them. Intense human transpiration requires a frequent floor and equipment cleaning routine. This routine, performed at short intervals can affect the indoor air quality. This study is aimed at showing varying concentration levels of the BTEX air pollutant at a gym in Rio de Janeiro, Brazil, specifically the spinning room. To monitor the air quality, activated charcoal cartridges (SKC) were used, coupled to a KNF pump with a flow rate of 1l min. For the extraction of each sample, a gas chromatographic analysis machine model 6890 was used coupled to an Agilent mass spectrometer model 5973. We analyzed a total of 34 air samples collected in the spinning room during active aerobic classes; the increased respiration from the subjects allow for a greater inhalation of VOCs. In Contrast, five samples were also collected outdoors; four of them were paired indoor / outdoor for comparative analysis of these pollutants. Among the volatile organic compounds analyzed, toluene was the most abundant BTEX found in this study, representing 81% of indoor VOCs. In all the indoor / outdoor paired samples, the concentration was higher in the interior samples, with one exception, benzene on 3/12/2010. Simple changes that can easily be done by man, such as the installation of rubberized flooring, regular maintenance of the air acclimatization equipment, and general cleanliness can greatly affect the indoor air quality. The conclusion achieved after looking at the BTEX measurements was that the indoor air was more polluted than the air outdoors. This air quality monitoring is still scarce in Brazil. Some efforts have been made in relation to confined spaces such as Ordinance n˚ 3523 from the Ministry of Health, which regulates the air of air-conditioned environments and Resolution n˚ 9 of the National Agency for Sanitary Vigilance, as well as Resolution CONAMA n˚ 3 by setting standards for air quality for some chemical compounds, unfortunately many chemical compounds are not yet legislated or receive proper attention in this matter, therefore not giving this indoor air pollution matter enough grounds to address the complexity of the subject

Em experimentos de Ressonância Magnética Nuclear (RMN) com Rotação da Amostra em Tomo do Ângulo Mágico (MAS), as bandas laterais são um problema comum na obtenção de espectros de alta resolução em sólidos. Em espectrômetros de alto campo magnético ou então, em sistemas que não dispõem de rotores de amostra de freqüência elevada, este problema é mais grave. Para facilitar a interpretação do espectro de alta resolução torna-se necessário suprimir estas bandas laterais. Nesta dissertação descrevemos um método simples de supressão das bandas laterais que consiste em variar a freqüência de rotação da amostra durante a aquisição do sinal, assim como, a instrumentação necessária para realizar esse experimento. Este método, que denominamos de Supressão das Bandas Laterais utilizando-se Freqüência de Rotação Baixa e Variável, baseia-se na dependência da posição das bandas laterais com a freqüência de rotação, reduzindo as coincidências entre suas posições durante a promediação, enquanto o sinal isotrópico permanece estável sempre no mesmo ponto do espectro. Para ilustrar a utilização dessa nova técnica, realizamos experimentos de RMN com o núcleo de 13C em amostras de hexametilbenzeno, tirosina, lignina e ácido húmico, e com o núcleo quadrupolar 79Br em amostras de KBr e NaBr + KBr / Sidebands in Magic-Angle-Spinning Nuclear Magnetic Resonance (MAS-NMR) experiments are a common problem for high field spectrometers or low spinning frequency systems. Although these sidebands may be used to gain information after they have been identified, it is necessary to eliminate then to simplify the interpretation of the spectra; we have recently succeeded in suppressing spinning sidebands by continuously varying the speed during the signal acquisition. This method, that we called variable low speed sideband suppression, relies on the speed dependent of the sideband positions. The purpose of this work is to describe a simple method and apparatus to suppress spinning sidebands in MAS-NMR experiments. The method allows a quick acquisition of the isotropic chemical shift spectra and works well even when the highest available spinning cannot clearly resolve the spinning sidebands. To illustrate the method, we present the 13C MAS-NMR spectra of a variety of sample acquired using cross-polarization and high power proton decoupling. Among the samples studied were: hexamethylbenzene, tyrosine, lignin and humic acid. And quadrupolar nuclei 79Br in the samples Kbr and NaBr + KBr

Um die wirtschaftliche Relevanz und die Flexibilität des Formdrückens zu erweitern, ist ein Maschinen- und Steuerungskonzept entwickelt worden, dass auch die Herstellung von nichtrotationssymmetrischen Bauteilen erlaubt. Neben experimentellen Untersuchungen zur Verfahrensentwicklung wurde ebenfalls eine numerische Verfahrensoptimierung des neu entwickelten Prozesses „Unrunddrücken“ durchgeführt, um unrunde Bauteile falten- und rissfrei sowie mit geringer Blechdickenreduktion herstellen zu können. In ersten experimentellen Untersuchungen wurden die technologischen Haupteinflussgrößen auf die Versagensformen Falten- und Rissbildung sowie die Blechausdünung ermittelt. Aufbauend auf diesen Ergebnissen ist ein kalibriertes Simulationsmodell erarbeitet worden, mit dem es möglich ist, das Prozessverständnis zu erhöhen und somit die Versagensfälle ganzheitlich über den Prozess zu betrachten. Die daraus gewonnenen Erkenntnisse wurden genutzt, um Optimierungsmaßnahmen für das Unrunddrücken abzuleiten. Es konnte experimentell nachgewiesen werden, dass sowohl die Falten- und Rissbildung als auch die Blechdickenreduktion durch die Optimierungsmaßnahmen deutlich reduziert werden können. Das in der vorliegenden Arbeit entwickelte Verfahren des Unrunddrückens stellt einen effizienten, kostengünstigen und vor allem flexiblen Fertigungsprozess für die Herstellung von nichtrotationssymmetrischen Bauteilen mit nahezu konstantem Blechdickenverlauf dar.

År 2016 var världsproduktionen av textilfibrer mer än 100 miljoner ton. Mycket av textilierna hamnar till slut i hushållssoporna som i Sverige förbränns till energiåtervinning; textilier som egentligen hade kunnat återanvändas eller materialåtervinnas. Textilåtervinning delas vanligtvis upp i tre olika kategorier: mekanisk, kemisk och termisk återvinning. Mekanisk återvinning är en typ av down cycling, som idag endast sker i liten skala. Ett av problemen som gör att mekanisk återvinning inte tillämpas i större utsträckning är att fibrerna i processen deformeras och blir för korta för att kunna spinnas till garn. Detta leder till en försämrad fiberkvalité i jämförelse med jungfruliga fibrer, vilket gör att återvinningsprocessen idag inte är hållbar ur ett ekonomiskt perspektiv.   I projektet har textila tillverkningsmetoder i form av garnspinning och trikåtillverkning undersökts för att se hur val av metoder kan främja en återvinningsprocess. En jämförelse av spinnmetoder gjordes mellan ett egentillverkat ringspunnet garn av samma sorts bomullsfibrer som i ett färdigtillverkat rotorspunnet garn. Från resultat av dragprovning gick det att utläsa att ringspunnet garn var starkare än rotorspunnet garn gällande både brottlast, brottöjning och tenacitet. Emellertid kunde ingen signifikant skillnad beräknas i varken brottlast eller brottöjning i testet av trikåvaror som stickats av vardera garnsort. Däremot fick trikåvara av rotorspunnet garn en större fiberförlust än motsvarande trikå av ringspunnet i test av nötningshärdighet.   Vid mätning av fiberlängd upptäcktes det att ett rotorspunnet garn innehåller kortare fibrer än ett ringspunnet garn, vilket betyder att fibrerna har förkortats i rotorspinningsprocessen då de båda garnen tillverkats från samma förgarn. Visuell analys av fibrerna från de olika processtegen genomfördes genom mikroskopering för att undersöka eventuell fysisk deformation. I analysen gick det att urskilja formförändringar hos fibrerna från de båda garnsorterna men man har inte kunnat bekräfta att de formförändringarna har en direkt koppling till möjligheten för mekanisk återvinning.   Ur ett hållbarhetsperspektiv behövs mer forskning på tillverkningsmetoders påverkan på återvinning av textil och möjligheten för återspinning. Detta skulle kunna möjliggöra att det redan i tillverkningsprocessen kan göras smarta val för ett materials cirkulära kretslopp. Det bör tittas närmare på hur processer kan göras ekonomiskt hållbara, även skillnader i miljöpåverkan hos de olika tillverkningsprocesserna bör undersökas. / 2016 was the year the world market of textile fibers surpassed the volume of 100 million tonnes. In Sweden today, lots of textiles end up in the garbage bin, later used for energy recovery even though most of the material could be reused or recycled. Textile recycling is often categorized in mechanical, chemical and thermal recycling. Mechanical recycling is a type of down cycling, which today only takes place on a small scale. One of the reasons, is the deformation of the fiber in the recycling process. When the textile fibers are mechanically processed their length become too short for the following re-spinning of yarn. This results in a deteriorated fiber quality in comparison with virgin fibers and complicates the vision of an economically sustainable recycling process.   In this thesis an investigation of how textile manufacturing processes affect a possible recycling process was made. Cotton fibers were spun to yarn by a ring spinning machine and compared with a prefabricated rotor spun yarn made of same sort of cotton fiber and later knitted in a circular knitting machine. The manufacturing processes influence on the mechanical properties of the yarns and the knitted fabrics were tested using a tensile testing machine and a Martindale tester. From the result of tensile testing the yarn, it was found that the ring spun yarn was stronger than the rotor spun in breaking strength, elongation and tenacity. Meanwhile no statistically differences in breaking strength and elongation in the knitted fabrics could be calculated. In the abrasion resistant test the knitted fabric of rotor spun yarn showed a greater loss in fiber than the knitted fabric of the ring spun.   Moreover a visual analysis of the fibers from various process steps was made by microscopy to investigate any physical deformation of the fibers. The fibers from the ring spun yarn was more wave- formed compared with fibers from the roving, while the tip of the fibers were flattened and less natural twisted in the rotor spun yarn. In the knitted fabrics, the fibers from the rotor spun yarn showed similar shape like the ones from the spinning process but the ring spun fibers were tip shaped. In addition an investigation of fiber length of fibers from roving, ring spun yarn and rotor spun yarn was made. The result showed a lower mean value of fibers from rotor spun yarn, which could cause problem in a future recycling process.   In conclusion, from a sustainability perspective more research is required on the impact of manufacturing processes on recycling of textile fibers. This could enable the possibility to make better choices in manufacturing, which would prolong the life of the textile fiber and minimize the environmental footprints.

No description available.

This master thesis focuses on applying deep neural networks (DNNs) in image-based condition monitoring of air-jet spinning machines, specifically focusing on the spinning pressure parameter. The study aims to develop a sensor system to detect structural defects in yarns and assign them to specific machine conditions. The research explores using DNNs to analyze images of yarns generated at different spinning pressures within the spinning box to create a rich dataset for training deep learning models. The study also evaluates the effectiveness of the DNN-based approach in detecting and classifying structural defects in yarns and determining the corresponding machine conditions. The outcomes of this research could potentially help textile enterprises improve the quality and efficiency of their yarn manufacturing processes.

The optimization of the spinning process and adjustment of the machine settings involve “Trial and Error” method resulting in the wasting of production time and material. This situation becomes worse in the spinning mills where the speed and material changes are frequent. This research includes the use of artificial neural networks to provide the thinking ability to the spinning machines to improve the yarn spinning process. Draw frame, being the central part of the spinning preparation chain and last machine to rectify the variations in the fed slivers is the main focus of the research work. Artificial neural network have been applied to the leveling action point at auto-leveler draw frame and search range of leveling action point has been considerably reduced. Moreover, the sliver and yarn characteristics have been predicted on the basis of draw frame settings using the artificial neural networks. The results of present research work can help the spinning industry in the direction of limiting of “Trial and Error” method, reduction of waste and cutting down the time losses associated with the optimizing of machines. As a vision for the future research work the concept of intelligent spinning machines has also been proposed. / Die Optimierung des Spinnprozesses und die Maschineneinstellung erfolgen häufig mittels „Trial und Error“-Methoden, die mit einem hohen Aufwand an Produktionszeit und Material einhergehen. Diese Situation ist für Spinnereien, in denen häufige Wechsel des eingesetzten Materials oder der Produktionsgeschwindigkeit nötig sind, besonders ungünstig. Die vorliegende Arbeit zeigt das Potenzial Neuronaler Netze, um die Spinnmaschine zum „Denken“ zu befähigen und damit die Garnherstellung effektiver zu machen. Die Strecke ist der zentrale Teil der Spinnereivorbereitungskette und bietet die letzte Möglichkeit, Inhomogenitäten im Faserband zu beseitigen. Der Fokus der Arbeit richtet sich deshalb auf diese Maschine. Künstlich Neuronale Netze werden an der Strecke zur Bestimmung des Regeleinsatzpunktes genutzt, womit eine beträchtliche Reduzierung des Aufwands für die korrekte Festlegung des Regeleinsatzpunkts erreicht wird. Darüber hinaus können mit Hilfe der Neuronalen Netze die Band- und Garneigenschaften auf Basis der Streckeneinstellungen vorausbestimmt werden. Die Resultate der vorliegenden Arbeit machen „Trial und Error“-Methoden überflüssig, reduzieren den Ausschuss und verringern die Zeitverluste bei der Maschinenoptimierung. Als Zukunftsvision wird eine Konzeption für intelligente Spinnmaschinen vorgestellt.

Les alliages conducteurs à haute tenue mécanique sont utilisés dans de nombreux domaines tels que le transport, l’énergie et l’industrie électronique. La demande en ces matériaux est croissante. Les alliages Cu-Be constituent à l’heure actuelle les matériaux conducteurs les plus résistants mais posent un problème de toxicité et de coût. Pour proposer une alternative à ces derniers, nous avons étudié des alliages Cu-Mg hypo-eutectiques. Deux voies de synthèse ont été utilisées afin d’obtenir des composites endogènes possédant une combinaison originale de propriétés structurelles et fonctionnelles : le refroidissement conventionnel et la solidification rapide par melt-spinning. Les microstructures obtenues ont en commun la présence d’agrégats eutectiques et diffèrent principalement par la dimension des paramètres métallurgiques tels que la taille de grains et la distance interlamellaire. Les systèmes présentent des forces motrices de transformation de phases importantes conduisant à une précipitation au cours d’un maintien thermique. L’investigation des propriétés mécaniques et électriques des alliages Cu-Mg montre que ces dernières égalent celles des alliages Cu-Be. En complément de l’approche expérimentale, nous avons adapté deux modèles : un modèle thermocinétique pour décrire l’évolution temporelle de la microstructure qui a lieu à haute température et un modèle mécanique permettant de rationaliser l'influence des paramètres microstructuraux sur les propriétés mécaniques et électriques. / Copper-based high strength conductive alloys are used in a myriad of applications such as transport, energy and electronic industries. The demand for these materials is booming. The strongest conductive alloy is based on the Cu-Be system which has the disadvantage of toxicity and cost. In an attempt to find an alternative to these, we have developed hypoeutectic Cu-Mg alloys. Two synthesis routes were applied to produce endogenous compounds with a unique combination of structural and functional properties: the conventional cooling and the rapid solidification by melt-spinning. The obtained microstructures share the presence of eutectic aggregates and differ mainly by the size of the metallurgical parameters such as grain size and interlamellar distance. The two systems provide high driving forces for phase transformations leading to precipitation during aging. The investigation of the mechanical and electrical properties of Cu-Mg alloys shows that they are equal to those of the Cu-Be alloys. In addition to experimental approach, we have adapted two models: a thermo-kinetic one to describe time evolution of the microstructure which takes place at high temperature and a mechanical one to rationalize the influence of microstructural parameters on mechanical and electrical properties.