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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.
11

Formulace inkoustů pro materiálový tisk chemických značek / Ink formulation for chemical labels printing

Martiniaková, Ivana January 2019 (has links)
This diploma theses is about the study of the effect of individual components of printing compositions intended for material printing of identificaton codes, read by X-ray fluorescence. Two printing technologies were used – screen printing and pad printing. The composition of the print compositions has been optimized in term of visual recognition, print repeatability, a dry matter content providing an X-ray fluorescence signal, as well as optimization of the material print process leading to the creation of invisible identification tags for archive documents.
12

Covers : social significance of apparel in portraiture

Farrell, Amanda 01 January 2007 (has links)
Throughout the years, portraiture has acted as a reflection of the changing aesthetics of both society and art. As traditions progressed from one way of thinking to new ideas, art and particularly portraiture has acted as a visual record of these changes. From the elaborate portrayals of the aristocrats and their lush surroundings, displaying their wealth and prestige to the expressionist paintings of the 20th century, which were more concerned with portraying the intensity of the paint and the emotional state of the sitter than an accurate physical account, the apparel and accoutrements of the sitter have remained as an important factor in determining a person's identity. The following images are a reflection of the emphasis that our youth and consumer driven society has put on the outward appearance of an individual. The constant barrage of advertising has forced us to either accept or reject the mainstream ideals of beauty and fashion. As a result, despite our best efforts to separate ourselves as unique individuals through apparel, often times the choices that we make are compelled by acceptance of a larger social group.
13

Effect of Manufacturing Technique on Electrochemical Response of a Sulfur Tolerant Planar Solid Oxide Fuel Cell Anode

De Silva, Kandaudage Channa R. 29 December 2008 (has links)
No description available.
14

Natural dyes: thickening madder, weld, and woad for screenprinting of Turkish inspired textile prints

Kritis, Matt January 1900 (has links)
Master of Science / Department of Apparel, Textiles, and Interior Design / Sherry J. Haar / The overarching goals of the project were to acknowledge both traditional and modern aspects of Turkish culture, inform designers and researchers of natural dye and screen printing methods, and advance the developing practices of sustainable design. Mixed methodologies of scientific and practice-based research guided the project. A collection of 25 prints inspired by the Anatolian region of Turkey were screen-printed with thickened natural dyes onto sustainable fibered fabrics. The research of traditional Turkish art and culture led to the inspirational concepts and brought the textile prints to fruition. Understanding the dyeing practices, regional traditions, and political rule of this nation informed the design process and directly influenced the composition and imagery of the designs. The final outcomes were exhibited at the Kansas State University student union art gallery. Research was conducted on the use of natural plant-based dyes madder, weld, and woad for screen-printing by determining the most effective thickener and thickening method. Thickening agents gum tragacanth and gum arabic were tested for fabric hand and the printed natural dyes were tested for colorfastness to light. Gum tragacanth at a ratio of .9875 g agent to 10 ml water emerged as the most smooth and pliable when evaluating fabric hand. Colorfastness to light was as expected for madder and woad with excellent to good fastness. Weld had an unexpectedly low rating indicating further study is needed. The developing practices of sustainable design were advanced as I used sustainable materials (natural dyes, natural gums, naturally fibered fabrics) and methods (hand screenprinting) throughout the project. The information from this project may be valuable to artisans to further develop their natural dye and screen-printing techniques; to researchers to provide a foundation for testing additional thickened dyes; and to industry professionals to modify their practices.
15

Light emitting polymers on flexible substrates for Naval firefighting applications

Brisar, Jon David 03 1900 (has links)
Approved for public release, distribution is unlimited / Display technologies in the current market range from the simple and cheap incandescent bulb behind a graphic overlay to the upwardly expensive flat panel high definition plasma display. To provide a foundation of understanding for Light Emitting Polymers (LEP), samples were imaged in a scanning electron microscope. This was preformed to identify a potential method for answering questions on polymer charge mobility and diffusion mechanisms, which are currently unknown. Light Emitting Polymer (LEP) displays offer a viable alternative to the active matrix style, when an application calls for information to be sent in a simple visible format. By using the flexibility of the fabrication process, LEP displays can be applied to offer a low cost, lightweight, and durable means of communicating information during shipboard damage control and firefighting. A unique screen printing method was used in collaboration with Add-Vision, to produce a prototype that was designed, fabricated and tested for use in Naval shipboard firefighting evolutions. The application of the LEP technology to shipboard damage control was motivated by the experience gained from being both the Officer in Charge of a Naval Firefighting School and from time in the Fleet as a Damage Control Officer. / Lieutenant, United States Naval Reserve
16

Viability and efficacy of probiotics printed on a textile material

Niehaus, Kim-Laura January 2016 (has links)
Hospital-acquired infections are to date a major challenge in the patient safety. The proliferation of pathogens such as Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae is often reported in connection with textiles, which represent a significant source of transmission. This leads most often to the contamination and cross-contamination of the hospitalized patient and the hospital staff. A promising approach and the immediate objective of this research is the application of probiotics to a textile fabric. They provide preliminary evidence in being able to inhibit pathogenic bacteria growth through their competitive mechanism. During this study, screen-printing was used as a method to apply probiotics on a polyester fabric. The viability of probiotics on the fabric was evaluated in the agar plate test method. Samples that exhibited a growth of grown out colonies were further tested regarding their efficacy towards the abovementioned pathogens. This was determined in a competition test, that included the individually inoculation of the samples with the different bacteria strains. Contact-angle measurements and abrasion resistance as well as the durability were tested in order to investigate the applicability of the fabric and scanning electron microscope images were taken to detect probiotics and to evaluate the quality of the print on the fabric. Major findings included that probiotics were able to survive on the polyester fabric and that these viable probiotics are further successful in the growth inhibition of pathogenic bacteria. Thereby their efficacy against pathogens is related to the viability the probiotics. As neither the probiotics used in this study, nor the other ingredients are considered as hazardous, this process is environment-friendly. This work increases the understanding of probiotics mechanism and their survival and competition behaviour on a textile material. It opens a way in the reduction of hospital-acquired infections through the beneficial effects of probiotics.
17

Microcapteurs de particules à base de micropoutres pour le contrôle de la qualité de l'air dans un véhicule automobile / Cantilever microsensors for air quality control in automotive vehicles

Grall, Simon 27 March 2019 (has links)
Les particules fines ont un impact réel sur la qualité de vie et la santé de millions de personnes dans les grandes zones urbaines, notamment en Asie. Pour les détecter et quantifier leur concentration, les capteurs de particules optiques sont les plus couramment étudiés, mais restent relativement chers et volumineux. Les transducteurs MEMS micropoutres sont largement utilisés pour des applications gravimétriques, pour la détection de particules ou de gaz, ce qui requiert des sensibilités massiques (Sm) élevées et des limites de détection (LOD) basses. Pour cela les micropoutres les plus adaptées sont celles ayant des fréquences de résonance (f0) et facteurs de qualité (Q) élevés, avec de faibles bruits de mesure et des masses faibles. Les micropoutres silicium sont couramment utilisées en tant que capteurs gravimétriques et sont de sérieux candidats pour répondre aux caractéristiques souhaitées. Cependant, la sérigraphie a le potentiel pour une fabrication moins chère, plus rapide et aussi à grande échelle. Pour ces micropoutres, l'actionnement et la lecture de f0 sont possibles par effet piézoélectrique. Bien qu'il existe des solutions inorganiques prometteuses sans plomb, les céramiques de titano-zirconate de plomb (PZT) possèdent encore les meilleures propriétés parmi les matériaux piézoélectriques. Des micropoutres fabriquées en technologie hybride couches épaisses sérigraphiées, à actionnement et lecture piézoélectriques intégrés, libérées à l'aide d'une couche sacrificielle polyester et avec co-cuisson de toutes les couches pour leurs libérations sont présentées ici. Différentes géométries ont été testées de 1 mm à 2 mm de large et de 1 mm à 8 mm de long, pour une épaisseur d'environ 100 μm. Une masse volumique ρ PZT = 7200 kg/m³ a été obtenue (≈ 93%ρ PZT massif). Enfin, avec une micropoutre 1×2×0,1 mm³, une sensibilité Sm ≈ 85 Hz/μm et une LOD de 70 ng ont été trouvées, permettant des applications en détection de particules. / Fine particulate matters (PM) have a real impact on the quality of life and health of millions of people in large urban areas, especially in Asia. In order to detect them and quantify their concentration, optical PM sensors are the most widely studied, but remain relatively expensive and bulky. MEMS microcantilever transducers are widely used for gravimetric applications, for PM or gas detection, which requires high mass sensitivities (Sm) and low limits of detection (LOD). A solution is to focus on microcantilevers with high resonance frequencies (f0) and quality factors (Q), low measurement noise and low masses. Silicon microcantilevers are commonly used as gravimetric sensors and are serious candidates to meet the desired characteristics. However, screen printing has the potential for cheaper, faster and large scale manufacturing. Such microcantilevers can be actuated and f0 read-out using the piezoelectric effect. Although promising lead-free inorganic solutions exist, titanium lead zirconate (PZT) ceramics still have the best properties among piezoelectric materials. Screen-printed microcantilevers manufactured in hybrid thick-film technology, with integrated piezoelectric actuation and read-out, released using a polyester sacrificial layer and with co-firing of all the layers are presented here. Different geometries were tested from 1 mm to 2 mm wide and from 1 mm to 8 mm long, for a thickness of about 100 μm. A density ρ PZT = 7200 kg/m³ (≈ 93%ρ PZT bulk) was obtained. With a 1×2×0.1 mm³ microcantilever, a sensitivity Sm ≈ 85 Hz/μm and a LOD of 70 ng were found, compatible with applications in PM mass detection.
18

Através do espelho: a constituição da pintura inicial de Andy Warhol (1956-1968) / Through the mirror: the constitution of negginer paiting of Andy Warhol (1956-1968)

Mesquita, Tiago dos Santos 26 June 2009 (has links)
Na década de60, Andy Warhol começou a trabalhar com as técnicas da serigrafia. Copiava imagens gráficas e fotográficas e as transferia diretamente para a tela. O artista abandonou os modos mais tradicionais de pintura e passou a trabalhar com a apropriação de imagens reproduzidas em série nos cartazes, fotografias, embalagens e no cinema. O uso destes clichês gráficos causou controvérsia. Uma série de discussões tentava entender a escolha do artista a partir de interlocuções dele com a obra de outros criadores e como uma interpretação de fatos da realidade social. A partir destas análises, este trabalho busca construir uma interpretação alternativa que entenda as razões para a modificação de procedimentos e linguagens na obra de Andy Warhol e o seu impacto na produção do século XX. / Andy Warhol started to work with the silkscreen techniques in the 1960s. Graphic and photographic images were copied and transferred straight onto canvas. The artist abandoned the traditional modes of painting and began working with the appropriation of serialized images from billboards, photos, packages and film. The use of such clichés was controversial. In several discussions, critics tried to understand Warhol\'s choices from his dialogue with other artists and as an interpretation of the facts of social reality. This study attempts to build an alternative interpretation that tries to understand the reasons for the modification of procedures and poetics in the Andy Warhol\'s work and his impact on the 20th century art.
19

Fabricação e caracterização de dispositivos eletroluminescentes produzidos com compósitos /

Quadros, Matheus Henrique. January 2019 (has links)
Orientador: Giovani Fornereto Gozzi / Resumo: Dispositivos Eletroluminescentes (EL) são comumente utilizados para iluminação ambiente e transmissão visual de informações, possuem uma enorme gama de aplicações em setores diversos, como para tratamento fototerápico e decoração. Entre as atuais tecnologias, os dispositivos produzidos com compósitos eletroluminescentes têm potencial de emprego em aplicações emergentes devido ao seu baixo custo, flexibilidade mecânica e escalabilidade. Estas vantagens tecnológicas estão atreladas ao fato destes dispositivos poderem ser produzidos utilizando-se técnicas de impressão gráfica, como por exemplo, a técnica de impressão serigráfica. Neste sentido, este trabalho tem como objetivo o desenvolvimento de dispositivos EL totalmente impressos utilizando a técnica de impressão serigráfica. Para tanto, a pasta condutora transparente (PCT) e a pasta de prata (PTF), ambas fornecidas pela empresa TICON, foram utilizadas para a produção de eletrodos transparentes e opacos, respectivamente. A camada ativa dos dispositivos foi produzida com o compósito eletroluminescente (PEL), o qual foi desenvolvido durante o presente estudo. Filmes dos materiais PCT, PEL e PTF foram depositados utilizando-se telas com diversas lineaturas e caracterizados com relação às suas propriedades morfológicas, elétricas e ópticas, com a finalidade de identificar as melhores lineaturas de telas serigráficas para o processamento de cada um dos materiais. Por fim, dispositivos EL do tipo LECEL (Light-Emitting Composite Ele... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Electroluminescent (EL) devices have a wide range of applications. Among current technologies, devices produced with electroluminescent composites have potential for use in emerging applications due to their low cost, flexibility and scalability. Scalability and cost-effectiveness are characteristics also related to device processing methods, amongst which printing techniques, such as screen-printing, are the most appropriated to achieve these goals. Therefore, this research regards on development of screen-printed EL devices. For this purpose, the transparent conductive paste (PCT) and the silver paste (PTF), both sourced by TICON, were used for transparent and opaque electrodes fabrication, respectively. The active layer of the devices have been produced with an electroluminescent composite (PEL) developed during the present study. We have produced screen-printed films with the PCT, PEL and PTF materials using screens with different mesh counts to study the influence of mesh count on the morphological, electrical and optical properties of the films. In addition, we have performed a study regarding the influence of mesh count on the EL device performance parameters. As main result, we have fabricated a screen-printed EL device, using screens with appropriated mesh counts for deposition of each material, which exhibited luminance of 50 cd/m2 (at 110 V) and turn-on voltage of (18 ± 2) V. / Mestre
20

Photodétecteurs organiques : conception, caractérisation et étude des mécanismes de défaillance / Organic photodetectors : design, characterization and study of degradation mechanisms

Kielar, Marcin 04 November 2016 (has links)
Cette thèse concerne l’étude des photodétecteurs à base de matériauxsemi-conducteurs organiques (OPDs) sensibles à la lumière verte. Ces travaux sedivisent en cinq parties distinctes. Tout d’abord, une recherche bibliographique suiviedes notions fondamentales sur les matériaux et le fonctionnement des dispositifsorganiques est présentée. Ensuite, un travail sur la méthodologie concernant lafabrication de bancs expérimentaux et sur la métrologie garantissant l’exactitude desdonnées expérimentales sont effectués. Les méthodes de fabrication etd’optimisation, notamment le dépôt par sérigraphie, sont également présentées. Lapartie expérimentale concerne l’étude de l’origine du courant d’obscurité dans lesstructures organiques à base des matériaux donneur et accepteur d’électrons, laconception et la caractérisation d’un photodétecteur organique à l’état de l’art dontles performances optoélectroniques sont proches des dispositifs inorganiques baséssur la technologie silicium. Enfin, l’étude des mécanismes de dégradation d’uncapteur organique est présentée mettant en avant le rôle de l’oxygène et l’humidité. / This thesis deals with the study of photodetectors based on organicsemiconductor materials (OPDs) that are sensitive to green light. There are five partsto this study. First, a bibliographic study following the fundamentals of organicmaterials and the working principle of organic photodetectors is presented. Then, anextended study on the methodology and metrology is detailed, which was carried outin order to design and fabricate new optoelectronic instruments that are able tocharacterize organic devices accurately. Fabrication and optimization steps oforganic photodetectors are detailed. The experimental section concerns the study onthe origin of the dark current in organic devices based on electron donor/acceptorsystems. A choice of materials is discussed and a full characterisation of state-of-theartorganic photodetectors is presented in detail. The measured performances wereclose to the those of inorganic sensors based on silicon technology. Finally, a studyof degradation mechanisms is presented which highlights the role of oxygen andmoisture.

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