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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.
41

Caractérisations optiques (LBIC, LBIV) et validation d’encres pour des cellules et des modules solaires photovoltaïques organiques / Optical characterizations (LBIC, LBIV) and validation of inks for organic photovoltaic cells and modules

Garuz, Richard 22 September 2015 (has links)
Les travaux de cette thèse sont en rapport avec la caractérisation de cellules solaires organiques et se déclinent suivant 3 axes :- Dans le cadre du projet IMPCELPHOTOR, nous avons développé un banc de caractérisation LBIC/LBIV permettant de cartographier des dispositifs OPV afin de visualiser et d’identifier les défauts de fonctionnement.- Dans le cadre du projet Européen SPrinTronics, nous avons travaillé sur l’amélioration des électrodes. Pour l’électrode collectrice d’électrons, nous avons sélectionné, testé et validé des encres métalliques à base de nanoparticules d’argent compatibles avec l’impression jet d’encre et permettant de réaliser des dispositifs OPV fonctionnels. Pour l’électrode collectrice de trous, nous avons testé des encres à base de nanofils d’argent et de nanotubes de carbone afin de remplacer l’ITO. Des résultats satisfaisants ont été obtenus avec une encre à base de nanofils d’argent. Cette dernière permet de réaliser des cellules semi-transparentes fonctionnelles sur verre et sur plastique. - Un travail sur l’aspect couleur d’un dispositif OPV a été mené au sein du projet PHASME. Nous avons mis en œuvre différentes techniques afin de modifier la couleur d’un dispositif OPV sans détruire ses performances photovoltaïques, le but étant de réaliser des modules polychromes. Nous avons développé simultanément un logiciel de colorimétrie permettant de contrôler et de prévoir le rendu de couleur dû à l’ajout de filtre coloré sur le dispositif OPV. / The work of this thesis is related to the characterization of organic solar cells and is structured in three independant parts :- Within the IMPCELPHOTOR project, we developed an experimental bench based on LBIC/ LBIV mapping, in order to visualize and identify defects within OPV device and modules.- Within the European SPrinTronics project, we worked on the improvement of OPV electrodes. For the top electrode, we selected, tested, and validated metallic inks based on silver nanoparticles compatible with inkjet printing. For the bottom electrode, we tested silver nanowires and carbon nanotubes inks to replace ITO. Satisfactory results have been obtained with an ink based on silver nanowires, which allowed us to obtain functional semi-transparent cells on glass and plastic.- Within the PHASME project, we worked on the visual aspect of a coloured OPV device. We implemented various strategies to change the color of an OPV device without altering its photovoltaic performance, the aim being to achieve full color modules. Simultaneously, we developed a colorimetric software to control and predict the color rendering on the final device (OPV plus filter).
42

Transformações nas artes gráficas no início do século XIX: os segredos para preparar tintas de impressão

Góes, Alcides Ferreira 21 May 2009 (has links)
Made available in DSpace on 2016-04-28T14:16:40Z (GMT). No. of bitstreams: 1 Alcides Ferreira Goes.pdf: 8273987 bytes, checksum: 0e3e99568082e4f5bc12b36ba488610b (MD5) Previous issue date: 2009-05-21 / Secretaria da Educação do Estado de São Paulo / Between the end of the century XVIII and the first half of the century XIX, a lot of modifications were in process in relation to the graphic arts. The search for improvements in printing images involved the own equipment, the form of fixation of the types to compose the matrix, the innovations in the distribution of the ink, new fittings between the matrix and the inking system, the mechanization of the printing press by the force of the vapor, and also alterations in the preparation of appropriate impression inks to that group of changes. Thus, in this work, we analyze recipes to make inks and their relationships with the processes and the changes involved in this art, starting the analysis of a manual of impression inks published in the first half of the century XIX - On the Preparation of Printing Ink: both Black and Coloured (1832), written by William Savage (1771-1844). We will approach the subject of the ink starting from the context in that the manual was published, evidencing practices of production on printing inks and the old knowledge registered in text. A group of factors will be presented to promote a better understanding of the influence of the ink in the impression process and your interface with the equipment, with the matrix and your distribution system of the printing press, trying to interpret in the work the secrets of the ingredients used in the revenues of an ink and mainly the way that the author treats on that subject / Entre o final do século XVIII e a primeira metade do século XIX, muitas modificações estavam em processo em relação às artes gráficas. As buscas por melhorias nos sistemas que geravam imagens a partir de uma impressora envolviam o próprio equipamento, as matrizes usadas no sistema de impressão, a forma de fixação dos tipos para compor a matriz, as inovações na distribuição da tinta, novos ajustes entre a matriz e o sistema de entintamento, a mecanização da impressora pelo uso da movimentação baseada na força do vapor, e também alterações no preparo de tintas de impressão adequadas a esse conjunto de mudanças. Assim, neste trabalho, analisaremos receitas de tintas e a sua relação com os processos e as mudanças envolvidas na época, tendo como ponto de partida a análise de um manual de tintas de impressão publicado na primeira metade do século XIX On the Preparation of Printing Ink: both Black and Coloured (1832), escrito por William Savage (1771-1844). Abordaremos a questão da tinta a partir do contexto em que o manual foi publicado, evidenciando as práticas de produção de tintas de impressão e os conhecimentos antigos registrados em texto. Um conjunto de fatores será apresentado para promover um melhor entendimento da influência da tinta no processo de impressão e a sua interface com o equipamento, com a matriz e o seu sistema de distribuição pela impressora, procurando interpretar na obra os segredos dos ingredientes usados nas receitas de uma tinta e principalmente a maneira que o autor trata sobre esse assunto
43

“Green” Aqueous Synthesis and Advanced Spectral Characterization of Size-Selected Cu2ZnSnS4 Nanocrystal Inks

Stroyuk, Oleksandr, Raevskaya, Alexandra, Selyshchev, Oleksandr, Dzhagan, Volodymyr, Gaponik, Nikolai, Zahn, Dietrich R.T., Eychmüller, Alexander 26 April 2019 (has links)
Structure, composition, and optical properties of colloidal mercaptoacetate-stabilized Cu2ZnSnS4 (CZTS) nanocrystal inks produced by a “green” method directly in aqueous solutions were characterized. A size-selective precipitation procedure using 2-propanol as a non-solvent allows separating a series of fractions of CZTS nanocrystals with an average size (bandgap) varying from 3 nm (1.72 eV) to 2 nm (2.04 eV). The size-selected CZTS nanocrystals revealed also phonon confinement, with the main phonon mode frequency varying by about 4 cm−1 between 2 nm and 3 nm NCs.
44

Elektrické vlastnosti tlustovrstvých past měřené v širokém rozsahu teplot / Electrical properties of thick film pastes measured in a wide temperature range

Gajdoš, Jiří January 2016 (has links)
The aim of this master’s thesis is to investigate the electrical properties of various thick-film resistor pastes in a wider temperature range. The thesis mainly focuses on a change in electrical resistance depending on temperatures, which extend to the cryogenic region. To achieve this, there is an overview of the thick-film technology properties, major technological procedures, principles of resistive pastes conductivity, methods of electrical resistance measuring, possible errors in measurement and methods of their minimization. The content of this work is also familiar with the characteristics of a cryogenic station, on this foundation was proposed the measurement procedure and created thick-film circuits for this station. After measurement in the interval 10 K to 350 K, there are subsequently evaluated the data and explains the principles of the conductivity of used pastes.

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