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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
401

Charakterisierung, Modellierung und Optimierung der Barriereeigenschaften von OP-Textilien

Aibibu, Dilibaier 26 October 2006 (has links) (PDF)
Durch die systematischen und umfangreichen experimentellen Untersuchungen werden in dieser Arbeit erstmalig die Einflüsse der textiltechnologischen Parameter des Garn- und Gewebebildungsprozesses auf die Porenstruktur und die davon abhängige Barrierewirkung von marktrelevanten OP-Geweben grundlegend analysiert. Daraus resultiert der Schwerpunkt der Arbeit – die Erarbeitung von Modellen – mit denen die Zusammenhänge zwischen strukturbedingten Einflussgrößen von Geweben und deren Barrierewirkung gegenüber kontaminierten Flüssigkeiten charakterisiert werden kann. Aufgrund des maßgeblichen Einflusses der Mikrostruktur auf das makroskopische Materialverhalten wird ein hierarchisches Strukturmodell eingeführt, welches zwischen der Makro-, Meso- und Mikroebene unterscheidet. Diese Strukturebenen erfassen die Gewebestruktur in unterschiedlichen Modellierungsniveaus. Die Systematisierungskriterien Garnfeinheit, Gewebebindung und Fadendichte beschreiben die Mesoebene. Die Filamentfeinheit und der Filamentquerschnitt sind wesentliche Kenngröße der Mikroebene. Das anhand des Darcy-Gesetzes entwickelte Modell für die Beschreibung der Mesoebene ist anschaulicher und beinhaltet den Einfluss der Bindung und der Formänderungen der Filamentgarne bei der Gewebeherstellung. Bei der Analyse der Porenstruktur werden mit Hilfe der optischen Methode – Bildanalyse – systematische Untersuchungen an der Morphologie des Gewebes durchgeführt, die bisher noch nicht realisierbar waren. Hier besteht die Möglichkeit, in das Gewebeinnere „hineinzusehen“ und sich nicht nur auf die funktionalen Parameter zu beschränken. Um die Transportmechanismen von Mikroorganismen unter praxisrelevanten Bedingungen zu simulieren, wird ein Verfahren entwickelt. Die Entwicklung erstreckt sich auf die Simulation des Drucks und der Reibung sowie die Simulation der im OP-Saal vorhandenen Flüssigkeiten mit synthetischem Blut und mit Mikrokugeln kontaminiertem Wasser. Das Verfahren ergänzt die optischen Untersuchungen und trägt zur Interpretation bei. Die qualitativen mikroskopischen Untersuchungen durch die Betrachtung der Gewebeoberfläche und -querschnitte unterstützen die Lokalisierung der Partikel im und auf dem Gewebe. Sie liefern interessante Aussagen und Informationen über die Durchgangsmechanismen von partikelbeladenen Flüssigkeiten durch das Gewebe. Der experimentelle Teil befasst sich mit der kritischen Auswahl und Charakterisierung repräsentativer OP-Textilien. Die wissenschaftlichen Fragestellungen werden an 6 repräsentativen PES-Filamentgeweben von 23 marktrelevanten PES-Filamentgeweben für OP-Textilien untersucht und beantwortet. Diese werden hinsichtlich des Einflusses der textiltechnologischen Parameter – Filamentfeinheit, -querschnitt, und Filamentgarnfeinheit sowie der webtechnischen Parameter – auf die strukturbedingte Barrierewirkung anhand der entwickelten Modelle und des Penetrationsversuches evaluiert. Auf diesen Ergebnissen aufbauend werden die Ansätze für die Optimierung der Gewebestruktur hinsichtlich der Barrierewirkung erstellt. Durch die Kombination von feinen Garnen mit hoher Fadendichte unter Ausnutzung von technologischen Möglichkeiten werden Mustergewebe aus PES-Mikrofilamentgarnen mit hoher Barrierewirkung hergestellt. Die experimentelle Untersuchung der am Institut für Textil- und Bekleidungstechnik entwickelten Mustergewebe und die theoretischen Modellrechnungen bestätigen das vorhandene textiltechnische Potenzial zur Optimierung von Mikrofilamentgeweben, d. h., einer weiteren Erhöhung der Widerstandsfähigkeit gegenüber partikelbeladenen Flüssigkeiten. Die Porenweiten in der Mesoebene können wirkungsvoll durch den Einsatz von feinen Filamentgarnen und das Erreichen der hohen Fadendichten in beiden Fadensystemen um die 50 % reduziert werden. Im Vergleich zu marktrelevanten OP-Geweben weisen die Mustergewebe eine erheblich hohe Barrierewirkung gegenüber synthetischem Blut und mit Mikrokugeln kontaminiertem Wasser auf. Diese Arbeit zur grundlegenden Analyse der strukturbedingten Barriereeigenschaften bietet Grundlagen für künftig notwendige Entscheidungen in der Produktentwicklung, Produktion, Produktnormung sowie Produktevaluierung. Sie kann in unterschiedliche Richtung fortgesetzt werden und die Optimierung flüssigkeits- und partikeldichter Gewebe im Gesundheitswesen, Reinraumtechnik im Speziellen oder von Schutztextilien im Allgemeinen, aber auch die Konkretisierung und Übertragung der Modellansätze betreffen.
402

Bromide characteristics and deformation mechanisms of naturally deformed rock salt of the German Zechstein Basin / Bromidcharakteristika und Deformationsmechanismen von natürlich deformiertem Steinsalz des Deutschen Zechsteinbeckens

Küster, Yvonne 30 June 2011 (has links)
No description available.
403

The terraces of the Conway Coast, North Canterbury: Geomorphology, sedimentary facies and sequence stratigraphy

McConnico, Tim January 2012 (has links)
A basin analysis was conducted at the Conway Flat coast (Marlborough Fault Zone, South Island, New Zealand) to investigate the interaction of regional and local structure in a transpressional plate boundary and its control on basin formation. A multi-tiered approach has been employed involving: (i) detailed analysis of sedimentary deposits; (ii) geomorphic mapping of terraces, fault traces and lineaments; (iii) dating of deposits by 14C and OSL and (iv) the integration of data to form a basin-synthesis in a sequence stratigraphy framework. A complex thrust fault zone (the Hawkswood Thrust Fault Zone), originating at the hinge of the thrust-cored Hawkswood anticline, is interpreted to be a result of west-dipping thrust faults joining at depth with the Hundalee Fault and propagating eastwards. The faults uplift and dissect alluvial fans to form terraces along the Conway Flat coast that provide the necessary relief to form the fan deltas. These terrace/fan surfaces are ~9 km long and ~3 km wide, composite features, with their upper parts representing sub-aerial alluvial fans. These grade into delta plains of Quaternary Gilbert-style fan deltas. Uplift and incision have created excellent 3D views of the underlying Gilbert-style fan delta complexes from topsets to prodelta deposits. Erosive contacts between the Medina, Rafa, Ngaroma and modern Conway fan delta deposits, coupled with changes in terrace elevations allow an understanding of the development of multiple inset terraces along the Conway Flat coast. These terraces are divided into five stages of evolution based on variations in sedimentary facies and geomorphic mapping: Stage I involves the uplift of the Hawkswood Range and subsequent increased sedimentation rate such that alluvial fans prograded to the sea to form the Medina fan delta Terrace. Stage II began with a period of incision, from lowering sea level or changes in the uplift and sedimentation rate and continued with the deposition of the Dawn and Upham fan deltas. Stage III starts with the incision of the Rafa Terrace and deposition of aggradational terraces in the upper reaches. Stage IV initiated by a period of incision followed by deposition of estuarine facies at ~8ka and Stage V began with a period of incision and continues today with the infilling of the incised valley by the modern fan delta of the Conway River and its continued progradation. New dates from within the Gilbert-type fan deltas along the Conway Flat coast are presented, using OSL and 14C dating techniques. Faulting at the Conway Flat coast began ~ 94 ka, based on the development of the Medina Terrace fan delta with uplift rates ~1.38~1.42 m/ka. The interplay of tectonics and sea level fluctuations continued as the ~79 ka Rafa Terrace fan deltas were created, with uplift rates calculated at ~1.39 m/ka. Detailed 14C ages from paleoforest (~8.4-~6.4 ka) in the Ngaroma Terrace and from the mouths of smaller streams have established uplift rates during the Holocene ~1-3 m/ka, depending on sea level.
404

Erstellung einer Sachbilanz-Studie und Modellierung des Lebensweges von Operationstextilien

Mielecke, Torsten 30 November 2009 (has links) (PDF)
Die vorliegende Ausgabe beschäftigt sich mit dem Thema „Erstellung einer Sachbilanz-Studie und Modellierung des Lebensweges von Operationstextilien". Das Ergebnis der Sachbilanz ist, dass die Mehrwegtextilien, im Vergleich zu den Einwegtextilien, einen geringeren Stoff- und Energiefluss erzeugen. Die Modellierung der Lebenszyklen ist in der Software Umberto vorgenommen. Sie visualisiert die Stoffflüsse zwischen den einzelnen Modulen des Lebensweges sehr gut. Es konnte verdeutlicht werden, dass der Wasserfluss der mengenmäßig größte Stoffstrom ist. Die größten Wasserverbräuche werden bei den Mehrwegtextilien in der Wäscherei und der Textilveredlung getätigt; bei den Einwegtextilien sind dies hingegen die Textilveredlung und die Kunststoffherstellung. Als Ergebnis der gesamten Überlegungen wird festgehalten, dass die erstellte Sachbilanz einen guten Hinweis auf die Umweltverträglichkeit der OP-Textilien gibt. Eine anschließende Ökobilanz, aufbauend auf den gewonnenen Daten, könnte die ermittelten Ergebnisse bestätigen.
405

Pl?sticos refor?ados a base de tecidos h?bridos: efeitos da anisotropia e geometria normativa na caracteriza??o mec?nica e da fratura

Oliveira, Jorge Fernando de Sousa 09 December 2013 (has links)
Made available in DSpace on 2014-12-17T14:07:22Z (GMT). No. of bitstreams: 1 JorgeFSO_TESE.pdf: 9384301 bytes, checksum: 94f6528a142b55c3b875e331722c4d8d (MD5) Previous issue date: 2013-12-09 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / As most current studies, reinforced plastics have been, in recent years, a viable alternative in building structural elements of medium and large, since the lightness accompanied by high performance possible. The design of hybrid polymer composites (combination of different types of reinforcements) may enable structural applications thereof, facing the most severe service conditions. Within this class of composite materials, reinforced the underlying tissues hybrid high performance are taking space when your application requires high load bearing and high rigidity. The objective of this research work is to study the challenges in designing these fabrics bring these materials as to its mechanical characterization and fracture mechanisms involved. Some parameters associated with the process and / or form of hybridization stand out as influential factors in the final performance of the material such as the presence of anisotropy, so the fabric weave, the process of making the same, normative geometry of the specimens, among others. This sense, four laminates were developed based hybrid reinforcement fabrics involving AS4 carbon fiber, kevlar and glass 49-E as the matrix epoxy vinyl ester resin (DERAKANE 411-350). All laminates were formed each with four layers of reinforcements. Depending on the hybrid fabric, all the influencing factors mentioned above have been studied for laminates. All laminates were manufactured industrially used being the lamination process manual (hand-lay-up). All mechanical characterization and study of the mechanism of fracture (fracture mechanics) was developed for laminates subjected to uniaxial tensile test, bending in three and uniaxial compression. The analysis of fracture mechanisms were held involving the macroscopic, optical microscopy and scanning electron microscopy / Conforme estudos mais atuais, os pl?sticos refor?ados v?m sendo, nos ?ltimos anos, uma alternativa vi?vel na constru??o de elementos estruturais de m?dio e grande porte, desde que a leveza acompanhada de alto desempenho seja poss?vel. A concep??o de comp?sitos polim?ricos h?bridos (combina??o entre tipos diferentes de refor?os) pode possibilitar aplica??es estruturais dos mesmos, frente ?s mais adversas condi??es de servi?os. Dentro dessa classe de materiais comp?sitos, os refor?ados a base de tecidos h?bridos de alto desempenho v?m tomando espa?o quando a sua aplica??o requer alto suporte de carga e alta rigidez. O objetivo desse trabalho de investiga??o ? o estudo da influ?ncia que esses tecidos trazem na concep??o desses materiais quanto a sua caracteriza??o mec?nica e mecanismos de fratura envolvidos. Alguns par?metros associados ao processo e/ou forma de hibridiza??o se destacam como fatores influenciadores no desempenho final do material tais como a presen?a de anisotropia, forma da trama tecido, processo de confec??o dos mesmos, geometria normativa dos corpos de prova, entre outros. Neste sentido, quatro laminados comp?sitos foram desenvolvidos ? base de tecidos de refor?os h?bridos envolvendo fibras de carbono AS4, kevlar 49 e vidro-E e como matriz a resina ep?xi ?ster vin?lica (DERAKANE 411-350). Todos os laminados comp?sitos foram constitu?dos com quatro camadas de refor?os. Dependendo do tipo de tecido h?brido, todos os fatores influenciadores acima mencionados foram estudados para os laminados. Todos os laminados foram fabricados industrialmente sendo empregado o processo de lamina??o manual (hand-lay-up). Todo o estudo da caracteriza??o mec?nica e do mecanismo de fratura (fratura mec?nica) foi desenvolvido para os laminados submetidos aos ensaios mec?nicos de tra??o uniaxial, flex?o em tr?s e compress?o uniaxial. As an?lises dos mecanismos de fratura foram realizadas envolvendo a macroscopia, microscopia ?tica e eletr?nica de varredura
406

Quand la scénographie devient urbaine : Nantes comme observatoire des fonctions du scénographe dans la fabrique de la ville / When the scenography becomes urban : Nantes as an observatory of the scenographer's functions in the city fabric

Gangloff, Emmanuelle 07 December 2017 (has links)
S’appuyant sur l’effervescence dont fait actuellement l’objet le terme de scénographie dans le milieu créatif, ce travail propose d’étudier l’apparition d’une fonction spécifique autour du concept de scénographie urbaine dans la fabrique de la ville contemporaine. En effet depuis les années 1980, dans un contexte d’essor de la ville événementielle, créative et culturelle nous assistons à une multiplication de propositions artistiques éphémères déployant des dispositifs scénographiques dans l’espace public qui font évoluer les modes d’action des acteurs de la fabrique urbaine (opérateurs culturels, artistes, gestionnaires publics et aménageurs). Entre théâtre et espace public, scène et ville, nous retracerons les origines de la scénographie pour ensuite s’intéresser à la scène nantaise qui est ici considérée comme un laboratoire des différentes formes que peut prendre la scénographie urbaine. En définissant le rôle du scénographe sur un terrain d’intervention spécifique, à savoir l’espace urbain, il s’agit par-là d’identifier un groupe professionnel émergent, les scénographes, au regard de l’évolution de leurs pratiques hors du théâtre. Puis, en resserrant la focale sur un territoire, nous caractérisons plus particulièrement la fonction de scénographie urbaine dans son acception contemporaine traduisant une évolution de la place de la création artistique dans la fabrique urbaine. Plus largement, cette étude met en question la production d’espaces urbains, révélatrice de tension entre nécessité fonctionnelle et conception d’espaces sensibles. Entre fabrique artistique et dynamique de récupération, ce travail nous renseigne sur un mode de faire la ville contemporaine à l’interface entre urbanisme du divertissement et utopie artistique. / Based on the current effervescence of scenography in the creative environment , this work proposes to study the appearance of a specific function around the concept of urban scenography in the fabric of the contemporary city. Since the 1980s, in a context of the development of event, creative and cultural city, we are witnessing a multiplication of ephemeral artistic proposals deploying scenographic devices in the public space that evolve modes of action of the actors of the urban factory (cultural operators, artists, public managers and developers). Between theater and public space, stage and city, we will trace the origins of the scenography and then take an interest in the Nantes scene, which is considered here as a laboratory of different forms that can take urban scenography. Infact, in urban space, it is an identifying an emerging professional group, the scenographers, about the evolution of their practices outside the theater. Then, by tightening the focus on a territory, we characterize more specifically the function of urban scenography in its contemporary meaning reflecting an evolution of the place of artistic creation in the urban factory. A larger scale, this study calls into question the production of urban spaces, revealing tension between functional necessity and the conception of sensitive spaces. Between artistic and dynamic recovery, this research informs us about an embodiment of the contemporary city at the interface between town planning of entertainment and artistic utopia.
407

Simulação de malha triangular: um estudo sobre a adaptatividade da malha / Cloth simulation using triangular mesh: A study of mesh adaptivity

Oliveira, Suzana Matos França de January 2013 (has links)
OLIVEIRA, Suzana Matos França de. Simulação de malha triangular: um estudo sobre a adaptatividade da malha. 2013. 73 f. Dissertação (Mestrado em ciência da computação)- Universidade Federal do Ceará, Fortaleza-CE, 2013. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-07-12T17:36:10Z No. of bitstreams: 1 2013_dis_smfoliveira.pdf: 12369786 bytes, checksum: f3aac3380bd894f258de70c6024bf91f (MD5) / Approved for entry into archive by Rocilda Sales (rocilda@ufc.br) on 2016-07-22T12:31:55Z (GMT) No. of bitstreams: 1 2013_dis_smfoliveira.pdf: 12369786 bytes, checksum: f3aac3380bd894f258de70c6024bf91f (MD5) / Made available in DSpace on 2016-07-22T12:31:55Z (GMT). No. of bitstreams: 1 2013_dis_smfoliveira.pdf: 12369786 bytes, checksum: f3aac3380bd894f258de70c6024bf91f (MD5) Previous issue date: 2013 / In the last decades, cloth animation has been the focus of much research, due to demands from the entertainment industry and from e-commerce. That type of animation is most often the result of a physics-based simulation and has a great computational cost. This work investigates how to reduce the computational cost of the simulation, by refining the mesh only in regions that need a fine level of detail. The fabric model consists of a triangular mesh and uses a spring-mass-damper system to compute the forces among the particles, which are located at the mesh’s vertices. The collision detection depends on the arrangement of the cloth model and the objects in the scene. The mesh is refined or simplified, taking into account the spring compression, collision and curvature, so the simulation uses a better mesh every time step. Therefore, this work’s main objective is to study the dynamic behavior of cloth, using a remeshing procedure in order to adapt the mesh. / A animação de tecido vem sendo estudada abundantemente nas últimas décadas por haver demanda na indústria do entretenimento bem como no comércio eletrônico de roupas. Esse tipo de animação, na maioria das vezes, é feita com base em simulação física, havendo muito gasto computacional. Esse trabalho tenta usufruir de vários modelos para diminuir esse gasto. É feito uma modelagem do tecido com uma malha triangular e usa-se um modelo massa-mola-amortecedor para simular as forças entre as partículas, que são os vértices dessa malha. Dependendo da disposição do modelo do tecido e dos objetos da cena, são detectadas colisões entre eles. A malha é discretizada ou simplificada, levando em consideração a compressão, a colisão e a curvatura das molas, para que seja usada uma malha boa em cada passo ao longo da animação. Portanto, o objetivo principal desse trabalho é estudar o comportamento do tecido utilizando o modelo de remalhamento para adaptar essa malha.
408

Architecture civile et formation du tissu urbain de Châteauneuf (Tours) du 10e au 14e siècle / Civil architectur and urban fabric of Châteauneuf (Tours) 10th -14 th centuries

Marot, Emeline 20 December 2013 (has links)
L'objectif de ce travail est d'appréhender les processus de la formation du tissu urbain de l'agglomération de Châteauneuf, créée autour de la collégiale Saint-Martin au cours du Moyen Âge à l'ouest de la cité de Tours. La complexité de cet espace, la densité et la diversité de la population à cette période ainsi que la richesse architecturale identifiée dans cette zone en font un terrain privilégié d'analyse de la fabrique urbaine, c'est-à-dire des relations entre l'espace urbain et les sociétés qui l'ont produit. L'étude des vestiges architecturaux médiévaux en pierre, associée à celle de sources complémentaires comme les sources textuelles, permet de proposer à la fois une synthèse typologique sur les constructions médiévales et une réflexion à l'échelle du parcellaire et de l'agglomération, pour mettre en évidence les formes urbaines et leurs transformations du 10e au 14e siècle / The purpose of this thesis is to understand the processes of the urban fabric in the town of Châteauneuf, created in the Middle Ages around the St-Martin's basilica, near the city of Tours. The complexity and density of the settlement together with the diversity of the inhabitants make this place a preferential area in order to study urban fabric and relations between space and societies which created it. The architectural analysis of stone buildings, combined with other data such as historical sources, allows the creation of a typological synthesis of the medieval buildings but also the analysis of the urban forms and their evolution between the 10th and the 14th centuries
409

Espace et société à Vendôme du 11e au début du 19e s. : fonctionnement et fabrique d'une ville intermédiaire sur le temps long / Space and society at Vendôme between the 11th and the beginning of the 19th century : functionning and urban fabric of the intermediate town in the longue durée

Simon, Gaël 12 December 2015 (has links)
L’étude du fonctionnement et de la fabrique de Vendôme du 11e au début du 19e s. propose une lecture différente des villes intermédiaires en montrant toutes la complexité du phénomène urbain dans un type de ville très souvent réduit à son origine castrale. La ville résulte en fait d’une multitude de temporalités et de spatialités où le temps des acteurs et de leurs projets n’est pas celui des structures. Tout d’abord, une approche théorique présente les concepts et la modélisation de l'espace urbain utilisés dans ce travail (1ère partie). Puis, l’étude de Vendôme dans la longue durée met en évidence quatre grandes phases dans le fonctionnement urbain, durant lesquelles les fins poursuivies par les acteurs et leurs répercutions spatiales sont étudiées (2ème partie). Enfin, sont analysées les structures de la ville, tant morphologiques que fonctionnelles, grâce à une modélisation de l’espace urbain prenant en compte la multiplicité des objets de la réalité urbaine (parcelle, réseau de voies, domaine construit…) évoluant chacun dans leur temporalité propre mais interagissant entre eux (3ème partie) / The study of the functioning and of the urban fabric of Vendôme between the 11th and the beginning of the 19th century offers a different interpretation of small towns showing the great complexity of the urban phenomenon in a type of town often regarded as the simple result of the construction of a castle. As a matter of fact, a town is the result of a large number of time and space units in which the time of the people involved in various projects is not the same as the time of structures. To start with, the concepts and the modeling rules of urban fabric used in this research are defined (part 1). Then, the study of Vendôme in the longue durée allows to distinct four main phases in the urban functioning for which the projects fulfilled by various actors are analyzed as well as their impact on urban space (part 2). Finally, urban structures are considered both from a morphological and functional point of view through a model based on the diversity of urban objects such as plots, street system, buildings etc. which have their own timing but interact with each other (part 3)
410

Modifica??o superficial do tecido 100% algod?o tratado com plasma

Freitas, Duciane Oliveira de 24 August 2009 (has links)
Made available in DSpace on 2014-12-17T14:57:52Z (GMT). No. of bitstreams: 1 DucianeOF.pdf: 2916882 bytes, checksum: 4dd79fd7f32c69ce44eb80c291049409 (MD5) Previous issue date: 2009-08-24 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The 100% cotton fabric (CO)* treated with plasma of methane CH4 has direct application in all areas that needs of aqueous solutions repellent material like coatings and uniforms applied biomedical, aeronautics, and automobile between others. 100% cotton fabric (CO) samples were treated by plasma with two differents atmosphere: Methane gas (CH4), treatment time was varied in 10 in 10 min. until 60 min., and mixture methane/argon (CH4/Ar), it was varied the proportion 1:9, 2:8, 3:7, 4:6, 5:5, 6:4, 7:3, 8:2 e 9:1, with treatment time of 30 minutes. In both, the fluxe was 5 sccm (second cubic centimeter), pressure 6 mbar, voltage 490 V and current 0,15A. The objective of work was measure the superficial tension of 100% CO then it treated with plasma, using contact angle measures of water and glycerol with the surface. The samples were tested after treatment, with 8 and 12 months to verify the superficial modification effects. It was verified an increase of hydrophobility with the Sessile drop values varied between 116,69? to 137,85? and it carried on after 12 months. The no treated samples shows contact angle equal 0?. OES analysis and Raman spectroscopy were accomplished. In the SEM analysis was verified oligomers. The plasma treatment is correct environmental, It turning greater than conventional treatments / O tecido 100% Algod?o (CO)* tratado com plasma de metano (CH4) tem aplica??o direta em todas as ?reas que necessitam de um material com maior repel?ncia a solu??es aquosas, como revestimentos e uniformes aplicados a ?rea biom?dica, aeron?utica, automobil?stica, entre outras. Amostras de tecido 100% CO foram tratadas com plasma utilizando duas atmosferas diferentes: g?s CH4, com tempos que variaram de 10 em 10 min. at? 60 min., e uma mistura de metano/arg?nio (CH4/Ar), em propor??es 1:9, 2:8, 3:7, 4:6, 5:5, 6:4, 7:3, 8:2 e 9:1, durante 30 min. O fluxo utilizado nos dois processos foi de 5 cm3/s (cent?metro c?bicos por segundo), a uma press?o de 6 mbar , voltagem de 490 V e corrente de 0,15 A. O objetivo do trabalho foi medir a varia??o da tens?o superficial do tecido 100% CO ap?s tratado com plasma; Utilizando medidas de ?ngulo de contato da ?gua e do glicerol com a superf?cie. As amostras foram testadas imediatamente ap?s o tratamento, com 8 e 12 meses, a fim de verificar a dura??o do efeito desta modifica??o superficial. Verificou-se um aumento da hidrofobicidade atrav?s dos valores do teste da gota s?ssil que variaram entre 116,69? a 137,85? e se mantiveram ap?s 12 meses; As amostras n?o tratadas apresentam ?ngulo de contato igual a 0?. An?lises de espectroscopia de emiss?o ?tica (EEO) e espectroscopia Raman (ER) foram realizadas, bem como, an?lise de microscopia eletr?nica de varredura (MEV) a qual confirmou presen?a de olig?meros. O processo a plasma ? ambientalmente correto e se torna superior em compara??o aos tratamentos convencionais

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