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Inkjet and Screen Printed Electrochemical Organic ElectronicsMannerbro, Richard, Ranlöf, Martin January 2007 (has links)
<p>Linköpings Universitet och Acreo AB i Norrköping bedriver ett forskningssamarbete rörande organisk elektrokemisk elektronik och det man kallar papperselektronik. Målet på Acreo är att kunna trycka denna typ av elektronik med snabba trycktekniker så som offset- eller flexotryck. Idag görs de flesta demonstratorer och prototyper, baserade på denna typ av elektrokemisk elektronik, med manuella och subtraktiva mönstringsmetoder. Det skulle vara intressant att hitta fler verktyg och automatiserade tekniker som kan underlätta detta arbete. Målet med detta examensarbete har varit att utvärdera vilken potential bläckstråleteknik respektive screentryck har som tillverkningsmetoder för organiska elektrokemiska elektroniksystem samt att jämföra de båda teknikernas för- och nackdelar. Vad gäller bläckstråletekniken, så ingick även i uppgiften att modifiera en bläckstråleskrivare avsedd för kontor/hemmabruk för att möjliggöra tryckning av de två grundläggande materialen inom organisk elektrokemisk elektronik - den konjugerade polymeren PEDOT och en elektrolyt.</p><p>I denna uppsats rapporteras om hur en procedur för produktion av elektrokemisk elektronik har utvecklats. Världens första elektrokemiska transistor som producerats helt med bläckstråleteknik presenteras tillsammans med fullt fungerande implementeringar i logiska kretsar. Karaktärisering av filmer, komponenter och kretsar som producerats med bläckstråle- och screentrycksteknik har legat till grund för den utvärdering och jämförelse som har gjorts av teknikerna. Resultaten ser lovande ut och kan motivera vidare utveckling av bläckstrålesystem för produktion av prototyper och mindre serier. En kombination av de båda nämnda teknikerna är också ett tänkbart alternativ för småskalig tillverkning.</p> / <p>Linköping University and the research institute Acreo AB in Norrköping are in collaboration conducting research on organic electrochemical electronic devices. Acreo is pushing the development of high-speed reel-to-reel printing of this type of electronics. Today, most demonstrators and prototypes are made using manual, subtractive patterning methods. More tools, simplifying this work, are of interest. The purpose of this thesis work was to evaluate the potential of both inkjet and screen printing as manufacturing tools of electrochemical devices and to conduct a comparative study of these two additive patterning technologies. The work on inkjet printing included the modification of a commercially available desktop inkjet printer in order to print the conjugated polymer PEDOT and an electrolyte solution - these are the two basic components of organic electrochemical devices. For screen printing, existing equipment at Acreo AB was employed for device production.</p><p>In this report the successful development of a simple system and procedure for the inkjet printing of organic electrochemical devices is described. The first all-inkjet printed electrochemical transistor (ECT) and fully functional implementations of these ECTs in printed electrochemical logical circuits are presented.</p><p>The characterization of inkjet and screen printed devices has, along with an evaluation of how suitable the two printing procedures are for prototype production, been the foundation of the comparison of the two printing technologies.</p><p>The results are promising and should encourage further effort to develop a more complete and easily controlled inkjet system for this application. At this stage of development, a combination of the two technologies seems like an efficient approach.</p>
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Inkjet and Screen Printed Electrochemical Organic ElectronicsMannerbro, Richard, Ranlöf, Martin January 2007 (has links)
Linköpings Universitet och Acreo AB i Norrköping bedriver ett forskningssamarbete rörande organisk elektrokemisk elektronik och det man kallar papperselektronik. Målet på Acreo är att kunna trycka denna typ av elektronik med snabba trycktekniker så som offset- eller flexotryck. Idag görs de flesta demonstratorer och prototyper, baserade på denna typ av elektrokemisk elektronik, med manuella och subtraktiva mönstringsmetoder. Det skulle vara intressant att hitta fler verktyg och automatiserade tekniker som kan underlätta detta arbete. Målet med detta examensarbete har varit att utvärdera vilken potential bläckstråleteknik respektive screentryck har som tillverkningsmetoder för organiska elektrokemiska elektroniksystem samt att jämföra de båda teknikernas för- och nackdelar. Vad gäller bläckstråletekniken, så ingick även i uppgiften att modifiera en bläckstråleskrivare avsedd för kontor/hemmabruk för att möjliggöra tryckning av de två grundläggande materialen inom organisk elektrokemisk elektronik - den konjugerade polymeren PEDOT och en elektrolyt. I denna uppsats rapporteras om hur en procedur för produktion av elektrokemisk elektronik har utvecklats. Världens första elektrokemiska transistor som producerats helt med bläckstråleteknik presenteras tillsammans med fullt fungerande implementeringar i logiska kretsar. Karaktärisering av filmer, komponenter och kretsar som producerats med bläckstråle- och screentrycksteknik har legat till grund för den utvärdering och jämförelse som har gjorts av teknikerna. Resultaten ser lovande ut och kan motivera vidare utveckling av bläckstrålesystem för produktion av prototyper och mindre serier. En kombination av de båda nämnda teknikerna är också ett tänkbart alternativ för småskalig tillverkning. / Linköping University and the research institute Acreo AB in Norrköping are in collaboration conducting research on organic electrochemical electronic devices. Acreo is pushing the development of high-speed reel-to-reel printing of this type of electronics. Today, most demonstrators and prototypes are made using manual, subtractive patterning methods. More tools, simplifying this work, are of interest. The purpose of this thesis work was to evaluate the potential of both inkjet and screen printing as manufacturing tools of electrochemical devices and to conduct a comparative study of these two additive patterning technologies. The work on inkjet printing included the modification of a commercially available desktop inkjet printer in order to print the conjugated polymer PEDOT and an electrolyte solution - these are the two basic components of organic electrochemical devices. For screen printing, existing equipment at Acreo AB was employed for device production. In this report the successful development of a simple system and procedure for the inkjet printing of organic electrochemical devices is described. The first all-inkjet printed electrochemical transistor (ECT) and fully functional implementations of these ECTs in printed electrochemical logical circuits are presented. The characterization of inkjet and screen printed devices has, along with an evaluation of how suitable the two printing procedures are for prototype production, been the foundation of the comparison of the two printing technologies. The results are promising and should encourage further effort to develop a more complete and easily controlled inkjet system for this application. At this stage of development, a combination of the two technologies seems like an efficient approach.
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Optimization Of Metalization In Crystalline Silicon Solar CellsDemircioglu, Olgu 01 August 2012 (has links) (PDF)
iv
ABSTRACT
OPTIMIZATION OF METALIZATION IN
CRYSTALLINE SILICON SOLAR CELLS
Demircioglu, Olgu
M. Sc. Department of Micro and Nanotechnology
Supervisor : Prof. Dr. Rasit Turan
Co-Supervisor : Assist. Prof. Dr. H. Emrah Ü / nalan
August 2012, 103 pages
Production steps of crystalline silicon solar cells include several physical and
chemical processes like etching, doping, annealing, nitride coating,
metallization and firing of the metal contacts. Among these processes, the
metallization plays a crucial role in the energy conversion performance of the
cell. The quality of the metal layers used on the back and the front surface of
the cell and the quality of the electrical contact they form with the underlying
substrate have a detrimental effect on the amount of the power generated by
the cell. All aspects of the metal layer, such as electrical resistivity, contact
resistance, thickness, height and width of the finger layers need to be
optimized very carefully for a successful solar cell operation.
In this thesis, metallization steps within the crystalline silicon solar cell
production were studied in the laboratories of Center for Solar Energy
Research and Application (GÜ / NAM). Screen Printing method, which is the
most common metallization technique in the industry, was used for the metal
layer formation. With the exception of the initial experiments, 6
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Printable Biosensors based on Organic Electrochemical Transistors with a Platinized Gate Electrode / Tryckbara biosensorer baserade på organiska elektrokemiska transistorer med en platinerad gate-elektrodBroman, Eva January 2012 (has links)
There is a great demand for low-cost disposable sensors in a variety of markets, such as the food chainand health care. No assay is performed more than that of glucose and approximately 85 % of the entirebiosensor market accounts for glucose biosensors. Each year, 6 billion glucose assays are performed andthe majority of them are based on electrochemical detection. Organic electrochemical transistors(OECTs) have favorable properties in terms of low operating voltages and have previously been used asbase for electrochemical detection of glucose. A low-cost disposable biosensor can be achieved by theuse of high throughput printing techniques. Up until now, no printable biosensors based on organic electrochemicaltransistors have been developed. In this thesis a printable miniaturized prototype for a glucose biosensor based on an OECT with a platinizedgate electrode has been designed, developed and evaluated. The biosensor has been functionalizedwith the enzyme glucose oxidase. Different platinum deposition techniques have been used to depositplatinum onto the printed carbon gate electrode: electrodeposition, platinum nanoparticle solutiondeposited either by inkjet printing or pipetting and thermal evaporation. The gate electrodes were characterized with cyclic voltammetry in hydrogen peroxide, ferricyanide andglucose. The characterizations revealed no significant differences between the different deposition techniques.However, with gate electrodes produced by printed carbon followed by electrodeposition ofplatinum it was possible to sense glucose in a concentration in the range of the values for diabetic persons.Thus, the electrodes are a promising option as gate electrodes in a glucose biosensor based on anOECT. The characteristics of the OECT revealed that the responses resembled a transistor.
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Vers un dispositif de diagnostic point of care intégré : utilisation de la capillarité ainsi que des procédés de thermoformage et de sérigraphie. / Towards an integrated device for point-of-care diagnostics : use of capillarity with thermoforming and screen-printing processes.Gosselin, David 06 October 2017 (has links)
Grâce aux technologies de la microfluidique (i.e. la manipulation d'un fluide dans un système ayant une dimension caractéristique sub-millimétrique), il est possible d'imaginer l'intégration de l'ensemble des fonctions ordinairement réalisées en laboratoire dans un système miniaturisé, réalisant ainsi un laboratoire sur puce. Cela peut ainsi permettre d'allier efficacité et bas-coût requis pour la réalisation de dispositif de diagnositcs médicaux utilisable en dehors d'infrastructure médicalisée, souvent appelés systèmes Point-of-Care. Pour la réalisation d'un tel dispositif, il semble important de concevoir l'intégration des différents composants du système d'une façon cohérente, et en prenant en compte l'ensemble des contraintes imposées par l'application finale ciblée. Le travail effectué au cours de cette thèse a ainsi été réalisé dans l'optique de proposer une réponse à cette problématique d'intégration dans le cadre du développement d'un système microfluidique de diagnostic Point-of-Care basé sur une réaction d'amplification d'ADN isotherme LAMP. Afin de pouvoir proposer un système bon marché et dont l'industrialisation est aisée, nous avons fait appel à l'utilisation du papier comme support et au thermoformage comme moyen de production. En effet à la fois l'industrie papetière et le procédé de thermoformage sont d'ores et déjà existant et proposent des fabrications en série. De plus, le faible coût du matériau et du procédé en question permettent d'envisager un dispositif final à bas-coût. Afin de pouvoir effectuer et détecter la réaction de LAMP la présence de fonctions actives telles qu'un chauffage et un outil de détection est nécessaire. Pour ces dernières, l'intégration a été réalisée par procédé sérigraphique. Le chauffage est effectué par effet Joule grâce au dépôt d'une couche d'encre conductrice à base de carbone. La détection est quant à elle faite par méthode potentiométrique, à l'aide d'électrode couverte de polyaniline. Il sera également montré que l'utilisation de ces méthodes de fabrication est pertinente en termes d'intégration car elles permettent une superposition des différentes fonctions actives, mais également leur intégration directement dans le système microfluidique. / Developments of microfluidics - the study of flows at the sub-millimetric dimensions - have made possible the integration of most of the macroscopic functions of laboratory fluidic systems in a miniaturized system, thus realizing a lab on a chip. This allows the conception of low cost, sensitive and efficient medical diagnostic device usable outside of a medical infrastructure. Such devices are called Point-of-Care (PoC) systems. The design and fabrication of such devices requires an elaborated and coherent integration that takes into account all the constraints imposed by the targeted final application.The work reported here, and performed during the PhD internship, is focused on the study of the concept and development of the integration of a PoC device based on the isothermal LAMP (Loop mediated AMPlification) reaction for the molecular analysis of DNA. In order to offer a cheap and easily industrialized system, we investigate the use of paper as the chip material and thermoforming as the mean to build the channels. These two techniques are currently used in the industry and their adaptation to the fabrication of such devices is easy and low-cost. In order to perform a LAMP reaction, specific functions such as a heating and a detection system are required. The integration of these functions was carried out using screen printing technology. Heating is done by Joule effect using a layer of carbon-based conductive ink. Detection is performed by a potentiometric method, using polyaniline-covered electrodes. It is shown that this approach is compatible with integration when the screen-printing layers are superposed. Besides they can be printed before thermoforming, resulting in a highly integrated system.
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Etude et optimisation de nouveaux types de capteurs pour la détection de polluants en milieu aquatique / Study and optimization of new types of sensors for the detection of pollutants in the aquatic environmentLapeine, David 13 December 2016 (has links)
Dans cette thèse, nous présentons l’étude et la réalisation de micro-capteurs pour les systèmes de gestion des risques naturels. Le cahier des charges était centré sur les possibilités de concevoir des capteurs de polluants pour la surveillance des zones lagunaires dans le sud montpelliérain. Ces capteurs devaient être conçus dans une démarche « faible coût », résistant aux contraintes du milieu et pouvant communiquer et temps réel. Le premier chapitre s’appuie sur une étude bibliographique des différentes méthodes de mesures qui peuvent être utilisées pour faire de la détection de polluants et des matériaux potentiels pour réaliser le capteur. La technique de mesure la plus appropriée pour répondre aux deux premiers points du cahier des charges s’appuie sur la réalisation de transducteurs acoustiques à base de PZT en envisageant un processus technologique basé sur la technique de sérigraphie. Après avoir justifié notre choix de la technique de dépôt par sérigraphie, nous avons détaillé dans le second chapitre le processus technologique, en commençant par la réalisation de l’encre PZT, puis par le dessin des masques et pour finir nous avons détaillé les étapes de dépôt et de fonctionnalisation des transducteurs sur substrat d’alumine et sans substrat. A partir de ces premières réalisations, nous avons présenté les moyens et outils de caractérisation nécessaires pour pouvoir évaluer les différentes étapes du processus technologique mis en place, avec une attention particulière portée sur la qualité du matériau PZT et sur ses propriétés piézoélectriques. Il s’agit d’une part d’études morphologiques (images MEB, profilomètre) et structurelles (diffraction X, EDX) et d’autre part de la mesure des grandeurs piézoélectriques et diélectriques (piézomètre, analyses spectrales et d’impédances). Dans le troisième chapitre nous avons abordé le volet système de cette étude, avec la réalisation de prototypes basés sur les transducteurs sérigraphiés développés au chapitre 2. Les capteurs réalisés ont été testés et étalonnés avec des solutions d’éthanol et de toluène. Pour cela les capteurs sérigraphiés ont été testés sur des bancs expérimentaux afin de valider la technique de la mesure du temps de vol des ondes acoustiques. Dans l’optique de la miniaturisation et de l’intégration du système nous avons mis en place une électronique de commande embarquée à l’aide d’un module dédié. Enfin, pour pouvoir affiner les mesures, nous avons vu que nous pouvions envisager de croiser/corréler plusieurs paramètres. C’est ainsi que nous avons développé un capteur sérigraphié pour la mesure de la conductivité électrique en milieu aquatique. A partir des premiers résultats expérimentaux obtenus nous avons pu valider le principe de la méthode. Dans le quatrième et dernier chapitre de ce manuscrit, nous avons présenté les toutes premières études et réalisations sur la technologie LTCC. En reprenant les paramètres du processus utilisés lors des dépôts sur substrat d’alumine, nous avons réalisé et caractérisé des transducteurs déposés sur une feuille de céramique LTCC. Les premières caractérisations morphologiques et piézoélectriques sont encourageantes et les premiers tests acoustiques ont montré que la génération d’ondes acoustiques était tout à fait possible et qu’une utilisation en vue de la réalisation de capteurs de polluants était envisageable avec cette technologie. Enfin, nous avons pu réaliser une première structure 3D intégrant une cavité d’analyse. Là encore les débuts sont très prometteurs même s’il reste encore beaucoup de travail de « réglage » pour améliorer cette technologie. De plus, cette première réalisation 3D, ouvre de nombreuses perspectives au niveau de l’équipe en vue du développement de nouveaux capteurs. / In this thesis, we introduce the study and implementation of micro-sensors for natural risk management systems. The specification focused on the possibilities to develop a pollutant sensor capable of detecting the presence of hydrocarbons in the lagoon environments of southern Montpellier.These sensors should be designed in a "low cost" gait, resistant to environmental constraints and able to communicate in real time. The first chapter is based on a bibliographical study of the different methods of measurement that can be used for the detection of pollutants and potential materials for making the sensor. The most suitable measurement technology to answer the first two points of the specification is based on the implementation of acoustic transducers made from PZT with a technological process using the screen-printing technique. After justifying our choice of screen-printing deposition technique, we have detailed in the second chapter the technological process: first with the achievement of PZT ink, then with the masks design, and finally with the steps deposition and functionalization of transducers on alumina substrate and without substrate. From these first achievements, we have submitted the means and characterization tools needed to evaluate the different steps of the technological process set up with a focus on the quality of the PZT material and its piezoelectric properties. It is first about morphological (SEM images, profilometer) and structural (XRD, EDX) studies, and then about the measurement of piezoelectric and dielectric values (piezometer, spectral and impedance analyses). In the third chapter we discussed the sensor, with the production of prototypes based on screen-printed transducers developed in Chapter 2. The sensors were tested and calibrated with solutions of ethanol and toluene. For this, the screen-printed sensors were tested in experimental benches to validate the measurement technique of the acoustic waves time of flight. In view of the miniaturization and the integration of the system, we have set an electronic control board with a dedicated module. Finally in order to improve the measurements, we have shown that we could consider crossing/correlating several parameters. Thus, we have developed a screen-printed sensor for the measurement of the electrical conductivity in aquatic environment. From the first experimental results we validated the principle of the method. In the fourth and final chapter of this manuscript, we presented the first studies and achievements on the LTCC technology. By repeating the process parameters used during deposition on alumina substrate, we realized and characterized transducers placed on on a LTCC ceramic sheet. The first morphological and piezoelectric characterizations are encouraging, and the first acoustic tests have shown that the generations of acoustic waves, and a use for the production of sensors of pollutants were possible with this technology. Finally we have been able to achieve a first 3D structure incorporating an analysis cavity. Here again, results are very encouraging, although "adjustments" are needed to improve the technology. Also this 3D realization opens up many opportunities for the team to develop new sensors.
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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)Tiago dos Santos Mesquita 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.
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Fabricação e caracterização de filmes espessos de CeO2 puro para aplicação em sensores de gás / Fabrication and characterization of thick films of pure CeO 2 for use in gas sensorsSantos, Camila Paixão [UNESP] 03 September 2016 (has links)
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Previous issue date: 2016-09-03 / Não recebi financiamento / Este trabalho apresenta e discute o uso do óxido de cério na fabricação de filmes espessos por “screen printing” para aplicações em sensores de gás. Nesse estudo o CeO2 puro foi obtido pelo método dos precursores poliméricos utilizando como resina precursora o citrato de céria. O “puff” – espuma resultante da primeira fase do tratamento térmico da resina- foi calcinado a 550, 600, 700 e 750°C. O pó foi caracterizado por termogravimetria (TG) e as propriedades estruturais, morfológicas foram avaliadas por difratometria de raios X (DRX), espectroscopia Raman, área de superfície por isotermas Brunauer, Emmett e Taller (BET) e microscopia eletrônica de varredura (MEV). A resposta sensora foi estudada em uma câmara de teste construída no Laboratório de Catálise e Superfícies do Instituto de Ciência de Tecnologia de Materiais (INTEMA) da Universidade de Mar del Plata. A TG mostrou a formação de óxido de cério a 550°C, temperatura relativamente baixa quando comparada com outros métodos. Mediante DRX todas as amostras mostraram picos correspondentes à fase pura de CeO2 o qual cristaliza em uma estrutura cúbica do tipo fluorita, entretanto, maiores temperaturas de calcinação mostraram aumento da cristalinidade e tamanho do cristalito. No espectro Raman, um forte pico em torno do 461 cm-1 foi detectado, atribuído às vibrações simétricas do Ce-O. A área de superfície BET dos pós foi de 301, 77 m2/g o que evidencia a formação de partículas muito pequenas e altamente reativas. As micrografias obtidas por MEV mostram a presença de diferentes tamanhos na forma de aglomerados. A caracterização da resposta sensora mostrou que o sensor fabricado a partir de pós de CeO2 puro apresenta um bom tempo de resposta, alcançando a melhor performance com temperatura de trabalho de 400 °C, tanto em atmosferas redutoras e oxidantes. A característica principal observada foi que os resultados são dependentes dos ciclos anteriores, a reprodutibilidade do sistema é garantida quando se apaga a “memória” do sistema, expondo-o ao vácuo. / This paper presents and discusses the use of cerium oxide in the production of thick films for "screen printing" for applications in gas sensors. In this study the pure CeO2 was obtained by the polymeric precursor method using as a precursor resin citrate ceria. The "puff" - resulting foam from the first stage of thermal treatment of the resin-calcined at 550, 600, 700 and 750 °C. The powder was characterized by thermogravimetry (TG) and structural, morphological were evaluated by X-ray diffraction (XRD), Raman spectroscopy, isothermal Brunauer surface area, Emmett and Taller (BET) and scanning electron microscopy (SEM) . The sensor response was studied in a test chamber built in the Laboratory of Catalysis and Surface Materials Technology Institute of Science (INTEMA), University of Mar del Plata. The thermogravimetry showed the formation of cerium oxide at 550° C, relatively low temperature compared with other methods. Upon XRD all samples showed peaks corresponding to pure CeO2 phase which crystallizes in a cubic fluorite type structure, however, higher calcination temperatures showed increased crystallinity and crystallite size. In the Raman spectrum, a strong peak around 461 cm-1 was detected, assigned to symmetric vibrations of the Ce-O. The BET surface area of the powders was 301, 77 m2 /g which shows the formation of very small and highly reactive particles. The SEM micrographs show the presence of different sizes in the form of agglomerates. The characterization of the sensor response showed that the sensors manufactured from pure CeO2 powder has a good response time, achieving better performance at 400 °C working temperature in both reducing and oxidizing atmospheres. The main feature observed was that the results are dependent on previous cycles, the system reproducibility is guaranteed when it deletes the "memory" of the system, exposing it to vacuum.
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Screen Printed Thermoelectric DevicesWillfahrt, Andreas January 2014 (has links)
Thermoelectric generators (TEG) directly convert heat energy into electrical energy. The impediments as to why this technology has not yet found extensive application are the low conversion efficiency and high costs per watt. On the one hand, the manufacturing process is a cost factor. On the other, the high-‐priced thermoelectric (TE) materials have an enormous impact on the costs per watt. In this thesis both factors will be examined: the production process and the selection of TE materials. Technical screen printing is a possible way of production, because this method is very versatile with respect to the usable materials, substrates as well as printing inks. The organic conductor PEDOT:PSS offers reasonable thermoelectric properties and can be processed very well in screen printing. It was demonstrated by prototypes of fully printed TEGs that so-‐called vertical printed TEGs are feasible using standard graphic arts industry processes. In addition, the problems that occur with print production of TEGs are identified. Finally, approaches to solve these problems are discussed.
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Materiálový tisk ozonových dozimetrů / Material printing of ozone dosimetersPetříčková, Zuzana January 2019 (has links)
This study presents various methods of measuring ozone and consolidates current state of knowledge in the field of disposable printed ozone dosimeters. The paper also identifies prospective dyes for preparation of ozone dosimeters available on the market. Information gathered from literature review was used to prepare dosimeters based on two different dyes. These were calibrated for screen printing technology and their sensitivity to ozone was optimized to achieve visual detectability. Prepared samples were observed and studied while being exposed to ozone. Then, long term mechanical and chemical properties of these were tested in order to identify appropriate conditions for storage.
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