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1

IOVINO, Giuseppe. "Properties of the O2 diffusion process in amorphous SiO2 nanoparticles." Doctoral thesis, Università degli Studi di Palermo, 2014. http://hdl.handle.net/10447/90989.

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Santos, Daniele Cristina Almeida Hummel Pimenta. "Obtenção e caracterização de materiais dopados SiO2-CdSe a partir de sonogeis de silica." [s.n.], 1994. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265224.

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Orientador: Iris Concepcion Linares de Torriani<br>Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica<br>Made available in DSpace on 2018-09-27T18:28:15Z (GMT). No. of bitstreams: 1 Santos_DanieleCristinaAlmeidaHummelPimenta_D.pdf: 23843878 bytes, checksum: 5825039acff4dd02da9447f4347a544f (MD5) Previous issue date: 1994<br>Resumo: O processo de obtenção de materiais pela via sol-gel tem-se mostrado muito interessante na obtenção de novos materiais como atesta o grande número de trabalhos desenvolvidos na última década. A possibilidade de obter materiais s
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Santos, Maria de Lourdes dos. "Reutilização de resíduo SiO2 como potencial na confecção de massa refratária de sílica." Universidade do Estado de Santa Catarina, 2013. http://tede.udesc.br/handle/handle/1642.

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Made available in DSpace on 2016-12-08T17:19:20Z (GMT). No. of bitstreams: 1 resumo.pdf: 33365 bytes, checksum: c0d79b06b712dd7d33a99ff2c405578a (MD5) Previous issue date: 2013-02-26<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior<br>The silica refractory is nowadays one of the most used linings in the world due to its excellent cost/benefit ratio. The silica sand is available in abundance in the market for use as a raw material for production of ordinary applications refractories, and this does not encourage the search for new usages of its wastes. However, in some industrial
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Izaak, T. I., D. О. Martynova, V. V. Maas, E. М. Slavinskaya, А. I. Boronin, and Y. W. Chen. "Synthesis and Properties of Ag / CuO / SiO2 Nanocomposites." Thesis, Sumy State University, 2013. http://essuir.sumdu.edu.ua/handle/123456789/35611.

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In this paper the composites Ag / SiO2 with regularly distributed in bulk matrix silver and copper oxide nanoparticles were synthesized. Herewith, copper ions was introduced into porous support at the stage of sol-gel synthesis. Sample Ag / CuO / SiO2 was tested by the catalytic reaction of CO oxidation and com-pared with Ag / SiO2. It was revealed that sample with introduced copper show lower activity .This fact can be explained by formation of silver cuprate during preparation of composite Ag / CuO / SiO2. Treatment by reaction mixture (CO and O2) led to release of silver in ionic, clusters
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Nunes, Eloiza da Silva [UNESP]. "Preparação e caracterização de nanocompósitos de Fe@SiO2, Fe@Fe3O4 e Fe3O4@PNIPAM." Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/124538.

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Made available in DSpace on 2015-07-13T12:10:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-02-05. Added 1 bitstream(s) on 2015-07-13T12:24:08Z : No. of bitstreams: 1 000826270_20160205.pdf: 226859 bytes, checksum: 619f39d8f546393cad7cff3abb1a91cb (MD5) Bitstreams deleted on 2016-02-05T13:56:02Z: 000826270_20160205.pdf,. Added 1 bitstream(s) on 2016-02-05T13:56:44Z : No. of bitstreams: 1 000826270.pdf: 25046020 bytes, checksum: fb29338aa8631d88b7bca10a5d22a9be (MD5)<br>Neste trabalho foi investigada a obtenção de nanopartículas de ferro metálico em diferentes meios não aquosos
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Barclay, Joshua David. "High Temperature Water as an Etch and Clean for SiO2 and Si3N4." Thesis, University of North Texas, 2018. https://digital.library.unt.edu/ark:/67531/metadc1404614/.

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An environmentally friendly, and contamination free process for etching and cleaning semiconductors is critical to future of the IC industry. Under the right conditions, water has the ability to meet these requirements. Water becomes more reactive as a function of temperature in part because the number of hydronium and hydroxyl ions increase. As water approaches its boiling point, the concentration of these species increases over seven times their concentrations at room temperature. At 150 °C, when the liquid state is maintained, these concentrations increase 15 times over room temperature. Du
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7

Shajkumar, Aruni. "Yolk-Shell Nanostructures Prepared via Block Copolymer Self-Assembly for Catalytic Applications." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2018. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-232735.

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Yolk-shell nanostructures/yolk-shell nanoparticles are defined as a hybrid structure, a mixture of core/shell and hollow particles, where a core particle is encapsulated inside the hollow shell and may move freely inside the shell. Of the various classifications of yolk-shell nanostructures, a structure with an inorganic core and inorganic shell (inorganic/inorganic) has been studied widely due to their unique optical, magnetic, electrical, mechanical, and catalytic properties. In the work presented here, among the different inorganic/inorganic yolk-shell nanostructures noble metal@silica yolk
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8

LORENZI, ROBERTO. "Silica based functional materials: - Charge transport in nanostructured SnO2: SiO2 thin films. - Second harmonic generation in niobium potassium silicate glasses. - Tapered silica optical microfibres for gas sensors." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2010. http://hdl.handle.net/10281/10933.

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"Charge transport in nanostructured SnO2:SiO2 thin films": Silica based nanostructured thin films grown on silicon substrates are promising materials for novel light emitter devices. In particular, tin dioxide is a wide band gap n-type semiconductor (Eg=3.6 eV) with an expected band-to-band emission centered in the ultraviolet (344 nm) region of the electromagnetic spectrum. Our group succesfully demonstrated UV emission from such systems, but at the beginning of my work many issues in charge transport processes needed to be explained. Aim of this project was to clarify electric transport a
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9

Gabsi-Wolf, Nadia. "Etude et modélisation de la précipitation de la silice selon le procédé Stöber en phase homogène et en émulsion." Thesis, Vandoeuvre-les-Nancy, INPL, 2007. http://www.theses.fr/2007INPL041N/document.

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L’étude de la précipitation de la silice amorphe à partir de TétraEthylOrtoSilicate (TEOS) et d’eau, selon le procédé Stöber, a permis de quantifier la cinétique de réaction par spectroscopie Infra Rouge à Transformée de Fourrier. Nous avons montré que la croissance des particules se fait par agrégation des nuclei, qui sont formés tout au long de la réaction. La transposition de ce procédé en microémulsion eau-dans-huile a permis de synthétiser des nanoparticules de silice de tailles contrôlées. L’hydrolyse du TEOS est ici dix fois plus faible qu’en phase homogène. Lors de l’ajout du TEOS à la
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Feltrin, Jucilene. "Estabilização a elevadas temperaturas da fase anatase com partículas submicrométricas de SiO2." reponame:Repositório Institucional da UFSC, 2012. http://repositorio.ufsc.br/xmlui/handle/123456789/100746.

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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Ciência e Engenharia de Materiais, Florianópolis, 2012<br>Made available in DSpace on 2013-06-25T22:14:09Z (GMT). No. of bitstreams: 1 315030.pdf: 3432223 bytes, checksum: 84054f849bb4c014ae9bc3dca9e31665 (MD5)<br>Este estudo descreve rotas desenvolvidas para obter a estabilidade da fase anatase em temperaturas acima de 900oC, através da mistura via seco de titânia e estabilizantes (quartzo e sílica amorfa), prensagem e tratamento térmico em condições industriais típicas da cerâmic
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Yin, YuYao. "Functionalization of the SiO2 Microparticle Surface by Dual-phase ATRP in Flow Reactor." Case Western Reserve University School of Graduate Studies / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=case1522781025079783.

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Heili, Manon. "Influence de l’histoire thermique sur la diffusion optique dans les préformes et les fibres optiques GeO2-SiO2 : F." Thesis, Paris 11, 2013. http://www.theses.fr/2013PA112272.

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Les fibres optiques sont présentes de manière incontournable dans les télécommunications et les réseaux d’accès à internet. Longs fils de verre fabriqués en silice vitreuse ultra pure, elles permettent de transmettre des informations sur de longues distances sous forme de signaux lumineux. Malgré leurs capacités de transmission déjà excellentes, la réduction des pertes optiques demeure un enjeu économique. En effet, en dessous d’une certaine atténuation, il est possible de supprimer des amplificateurs localisés dans des zones peu accessibles où leur installation est très couteuse. L’objectif d
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13

Soulé, Samantha. "Synthèse et caractérisation de nanomatériaux hybrides de type Au@SiO2 : potentialités dans le domaine de la nanomédecine." Thesis, Pau, 2015. http://www.theses.fr/2015PAUU3033/document.

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Depuis une décennie, dans le domaine de la nanomédecine, les recherches s’orientent de plus en plus vers l’élaboration de nanomatériaux multifonctionnels avec l’espoir d’améliorer la précision des diagnostics ou encore l’efficacité des traitements à mettre en place. Dans ce contexte, notre travail visait à mettre en œuvre des nanoparticules hybrides Au@SiO2 de type cœur-coquille associant les propriétés photothermiques de la phase métallique à la fonction délivrance de médicaments du réseau inorganique poreux. Avec le greffage d’obturateurs organiques à l’entrée des pores de la silice, ces ass
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14

Korkmaz, Erdural Beril. "Photocatalytic Antimicrobial And Self-cleaning Properties Of Titania-silica Mixed Oxide Thin Films." Phd thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12615137/index.pdf.

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In this study photocatalytic antibacterial and self-cleaning activities of TiO2-SiO2 thin films as a function of TiO2/SiO2 ratios were investigated. TiO2-SiO2 mixed oxides were synthesized by sol-gel method and coated over soda-lime glass plates by dip coating technique. Escherichia coli was used as a model microorganism for the photocatalytic antibacterial tests. Degradation rate of methylene blue (MB) molecules was used to characterize photocatalytic self-cleaning activities of thin film surfaces. The maximum antibacterial activity was achieved over 92 wt% SiO2 containing thin films. Howe
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15

Gazal, Yoan. "Etude de la croissance de couches minces de TiO2 et TiO2 / SiO2 par torche plasma micro-ondes à la pression atmosphérique." Thesis, Limoges, 2015. http://www.theses.fr/2015LIMO0088/document.

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Un dispositif de dépôt chimique en phase vapeur à l’air libre, utilisant une torche à injection axiale (TIA), a été développé pour l’élaboration de couches minces de TiO2 et TiO2/SiO2. Les effets des paramètres de dépôt comme la distance torche-substrat (d), la puissance micro-onde incidente et le débit de précurseur de titane (TTIP) sur (i) la morphologie et (ii) la structure cristalline des couches ont été étudiés. Dans la mesure où ces couches sont appliquées dans le domaine de la photocatalyse hétérogène, l’optimisation du procédé vise dans un premier temps à permettre l’obtention d’une gr
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16

Marcasso, Tatiani. "Preparação e caracterização de compósitos SiO2/Nafion® e TiO2/Nafion®." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/46/46134/tde-18082011-102732/.

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O presente trabalho tem como objetivo principal a preparação e a caracterização de compósitos sílica/Nafion® e titânia/Nafion®, sendo o óxido a fase maioritária. A incorporação do Nafion® se deu durante o processo sol-gel. Foram testadas duas rotas sintéticas para a sílica, sendo uma delas catalisada por HNO3 e a outra por NH4OH, e uma rota, catalisada por HNO3, para a titânia. Posteriormente, as amostras foram calcinadas e analisadas por diversas técnicas. A DRX mostrou que as sílicas obtidas eram amorfas e que as amostras de titânia, por sua vez, apresentavam as fases cristalinas anatase e b
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Ozensoy, Emrah. "Polarization modulation infrared reflection absorption spectroscopy for heterogeneous catalytic applications at elevated pressures." Diss., Texas A&M University, 2003. http://hdl.handle.net/1969.1/2201.

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This dissertation focuses on bridging the pressure and complexity gap between heterogeneous catalysis and surface science by introducing new instrumental tools that can operate under catalytically relevant conditions (i.e. atmospheric pressures and temperatures higher than room temperature). Thus, some of the few detailed examples of the polarization modulation infrared reflection absorption spectroscopy (PM-IRAS) as an in situ vibrational spectroscopic tool for the elevated-pressure investigation of gas/solid interfaces on planar single crystal model catalyst systems were presented in this w
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Silva, Erik dos Santos. "Processamento e caracteriza??o de comp?sitos Poli(METACRILATO DE METILA)/S?lica (PMMA/SiO2)." Universidade Federal do Rio Grande do Norte, 2013. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12787.

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Made available in DSpace on 2014-12-17T14:07:08Z (GMT). No. of bitstreams: 1 ErikSS_DISSERT.pdf: 3248804 bytes, checksum: 7241bc799da79c157edae8da7a7966cc (MD5) Previous issue date: 2013-04-05<br>Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior<br>Currently the search for new materials with properties suitable for specific applications has increased the number of researches that aim to address market needs. The poly (methyl methacrylate) (PMMA) is one of the most important polymers of the family of polyacrylates and polymethacrylates, especially for its unique optical properties a
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Heyl, Hanna Verena. "Phase Relations in the YBa2Cu3O7-x - SiO2 System and the Impact on Superconducting Fibers." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/95058.

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This dissertation presents the first reported identification and analyses of the phase relations in the YBa2Cu3O7-x (YBCO)-SiO2 system at elevated temperatures. In this regard, a rigorous characterization study of the reaction phases within YBCO glass fibers, heat-treated YBCO+SiO2 pellets, rapid thermally annealed YBCO+SiO2 rods and rapid thermally annealed YBCO powder inside a fused silica tube is provided. These analyses are based on a vast set of generated novel results obtained using energy dispersive spectroscopy analyses on an environmental scanning electron microscope, X-Ray diffractio
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Duma, Viorel. "Heterogen katalysierte Gasphasen-Epoxidation von Propen an FeOx/SiO2-Katalysatoren." Doctoral thesis, Universitätsbibliothek Chemnitz, 2001. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-200100686.

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Im Rahmen der vorliegenden Arbeit wurde eine neuartige Methode und die entsprechenden Katalysatoren für die heterogen katalysierte Gasphasen-Epoxidation von Propen entwickelt und optimiert. Das Propen wurde an FeOx/SiO2-Katalysatoren mit N2O als Oxidationsmittel epoxidiert. Die Katalysatoren wurden mittels XRD, TEM, XPS, Physi- und Chemisorption, TPR/TPO, TPD und IR untersucht und charakterisiert. Der Einfluß der Reaktionsbedingungen auf die Oxidationsergebnisse wurde bestimmt und Untersuchungen zum Reaktionsablauf durchgeführt. Es wurden Selektivitäten zu Propenoxid von 40-70%, bei Propenumsä
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Eker, Zeynep. "Preparation And Characterization Of Titania-silica-gold Thin Films Over Ito Substrates For Laccase Immobilization." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/3/12611022/index.pdf.

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The aim of this study was to immobilize the redox enzyme laccase over TiO2-SiO2-Au thin film coated ITO glass substrates in order to prepare electrochemically active surfaces for biosensor applications. Colloidal TiO2-SiO2-Au solution was synthesized by sol-gel route and thin film was deposited onto the substrates by dipcoating method. The cysteamine was utilized as a linker for immobilization of enzyme covalently through gold active sites. Preliminary studies were conducted by using invertase as model enzyme and Pyrex glasses as substrates. The effect of immobilization parameters such as im
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Kong, Pei San. "A novel hydrophobic ZRO2-SIO2 based heterogeneous acid catalyst for the esterification of glycerol with oleic acid." Thesis, Toulouse, INPT, 2018. http://www.theses.fr/2018INPT0042.

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Le faible coût du glycérol sur le marché a conduit à des études approfondies sur la conversion du glycérol en dérivés à valeur ajoutée. Ce travail se concentre sur l'estérification catalytique du glycérol, avec l'acide oléique, réaction d’intérêt industriel en raison de la grande valeur commerciale des produits obtenus. Dans ce travail, un nouveau catalyseur acide hétérogène présentant une surface hydrophobe a été développé sur le support ZrO2-SiO2 car un catalyseur acide solide tolérant à l'eau est essentiel pour les réactions d'estérification en milieu biphasique produisant de l'eau. Le cata
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Macheli, Lebohang. "Silica modified Co3O4 nanocubes as a model system for metal-support interaction in Co/SiO2 catalyst for Fischer-Tropsch synthesis." Master's thesis, University of Cape Town, 2014. http://hdl.handle.net/11427/13226.

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Includes bibliographical references.<br>The aim of this study was to study the interaction between the silica and cobalt crystallites using a model of Co3O4-nanocubes whose surface was modified with tetraethyl orthosilicate. The model systems were prepared in two steps, viz. synthesis of the cobalt(III,II) oxide nanocubes via the sodium dodecylsulphate assisted oxidative precipitation and a surface modification of the nanocubes with tetraethyl orthosilicate. The obtained morphology and in particular the average crystallite size of Co3O4 nanocubes is affected by the temperature at which the rea
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Cagnani, Giovana Rosso. "Fabricação de sistemas nanoestruturados de SiO2 pela técnica Roll-to-Roll e aplicações em fotônica." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/18/18158/tde-24102018-093142/.

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Pesquisas de desenvolvimento na área de fotônica impressa vão desde sistemas óticos de reflexão e espalhamento de luz, até moduladores e dispositivos fotônicos na escala nanométrica. Para isso, os dispositivos fabricados utilizam das propriedades de estruturas capazes de controlar a emissão e propagação luminosa a níveis elevados de confinamento e guiamento. Estas estruturas são conhecidas como cristais fotônicos. No entanto, os cristais fotônicos encontram dificuldades de aplicação, pois são produzidos por métodos intermitentes e em pequena escala. Neste sentido, este estudo contribuiu para o
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Alrumaih, Mohammed Aulwai. "Investigation of the Effect of Nano SiO2 on Porosity." University of Dayton / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=dayton155744355992274.

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Cinar, Merve. "Enzyme Immobilization On Titania-silica-gold Thin Films For Biosensor Applications And Photocatalytic Enzyme Removal For Surface Patterning." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/3/12611021/index.pdf.

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The aim of this study was to investigate the viability of patterning by immobilization, photocatalytic removal, and re-immobilization steps of the enzyme on photocatalytically active thin films for biosensor fabrication purposes. For this aim, TiO2-SiO2-Au sol-gel colloids were synthesized and deposited on glass substrates as thin films by dip coating. Cysteamine linker was assembled on gold nanoparticles to functionalize thin films with amine groups for immobilization of model enzyme invertase. Effect of immobilization temperature, enzyme concentration of the immobilization solution and immob
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Khan, Latif Ullah. "Nanomateriais ópticos e magnéticos contendo matrizes de Fe3O4 e SiO2 funcionalizadas com calixareno e complexos de terras raras." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/46/46136/tde-20072015-151110/.

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Neste trabalho são investigados o designer e a fabricação nanomateriais magnéticos e luminescentes sofisticados bifuncionais baseados em Fe3O4 e complexos de RE3+. Portanto, novos nanomateriais Fe3O4@calix-Eu(TTA) e Fe3O4@calix-Tb(ACAC) emissores vermelho e verde superparamagnéticos foram preparados pelo método one-pot. Neste caso, o ligante calixareno quimicamente modicado como surfactantes para estabilizar as nanopartículas de Fe3O4. O ligante calixareno proporciona uma superfície quimicamente modificada e estabilidade coloidal das nanopartículas magnetitas. Consequentemente, as nanopartícul
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Hrout, Ghassan. "Investigate the Effect of Nano SIO2 on Porosity, Compressive and Flexural Strengths of Concrete Has 2% Fly Ash and 2% Silica Fume." University of Dayton / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1608296326325322.

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Alshammari, Saleh Majed. "The Effect of Nano Silica on Porosity and Strength." University of Dayton / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1544644895468858.

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Lima, Camila Diana. "S?ntese de ?steres met?licos de ?cidos graxos (biodiesel) e de ?steres benz?licos por rea??o qu?mica com catalisadores heterog?neos baseados em NbCl5 e SiO2-Nb." UFVJM, 2017. http://acervo.ufvjm.edu.br/jspui/handle/1/1370.

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Oliveira, Junior Gelson Cerqueira de. "Aplica??o de catalisadores a base de SiO2-SO3H na s?ntese de biodiesel: estudo cin?tico do processo de transesterifica??o de triacilglicerideos." UFVJM, 2015. http://acervo.ufvjm.edu.br/jspui/handle/1/1444.

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Data de aprova??o retirada da vers?o impressa do trabalho.<br>Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2017-08-30T18:13:36Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) gelson_cerqueira_oliveira_junior.pdf: 2578577 bytes, checksum: 83cb8ab9378ea856fed151a0f1c1992d (MD5)<br>Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2017-08-30T18:51:12Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) gelson_cerqueira_oliveira_junior.pdf: 257857
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Vallés, Lluch Ana. "P(EMA-co-HEA)/SiO2 hybrid nanocomposites for guided dentin tissue regeneration: structure, characterization and bioactivity." Doctoral thesis, Universitat Politècnica de València, 2008. http://hdl.handle.net/10251/3795.

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Se sintetizaron nanocompuestos híbridos en bloque de poli(etil metacrilato-co-hidroxietil acrilato) 70/30 wt%/sílice, P(EMA-co-HEA)/SiO2, con distintas proporciones de sílice hasta el 30 wt%. El procedimiento de síntesis consistió en la copolimerización de los monómeros orgánicos durante la polimerización sol-gel simultánea de tetraetoxisilano, TEOS como precursor de sílice. El TEOS se hidroliza eficientemente y condensa dando lugar a sílice, y presenta una distribución homogénea en forma de agregados inconexos de nanopartículas de sílice elementales en los híbridos con bajos contenidos de sí
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Soumbo, Marvine. "Adsorption des protéines sur les surfaces de couches minces de silice seules ou additivées de nanoparticules d'argent : impact sur les forces d'adhésion de Candida albicans." Thesis, Toulouse 3, 2019. http://www.theses.fr/2019TOU30258.

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Dans de nombreux secteurs, l'adhésion microbienne sur les surfaces est la source de multiples impacts négatifs. Cette étape est considérée comme préliminaire au développement de biofilm et peut être influencée par la présence d'un film conditionnant engendré par l'adsorption des protéines sur la surface. Ainsi, les stratégies visant une intervention au moment de la phase initiale d'adhésion représentent une approche appropriée pour prévenir la bio-contamination des surfaces et nécessitent une compréhension à l'échelle moléculaire. Dans ce contexte, les matériaux nanocomposites à base de nanopa
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Remonte, Ádamo Rossano Vicentini. "Síntese e caracterização de nanocompósitos vitrocerâmicos transparentes a base de SiO2-ZrO2 dopados com íons Eu3+ e Er3+ via processo sol-gel." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/59/59138/tde-26052009-165942/.

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A preparação de vitrocerâmicas transparentes a base de SiO2-ZrO2 dopado com íons Eu3+ e Er3+ através da metodologia sol-gel foi o objetivo desta dissertação. São apresentados resultados estruturais e óticos deste sistema, em função de temperatura, tempo e composição (variando-se a concentração de zircônia). Os sóis foram preparados em meio ácido e deixados em repouso até evaporação total do solvente, obtendo-se assim monolitos amorfos, os quais foram submetidos a tratamentos a 900, 1000 e 1100ºC durante 2, 4 e 8 horas visando eliminação de resíduos orgânicos, moléculas de água, grupos hidroxil
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Delgado, Tardáguila Rosario. "Experimental investigations on nuclear aerosols in a severe accident." Doctoral thesis, Universitat Politècnica de València, 2016. http://hdl.handle.net/10251/63243.

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[EN] In case of a severe accident in a NPP fission products are released from the degraded fuel and may reach the environment if their confinement is lost and/or bypassed. Given the high radio-toxic nature of nuclear aerosols for environment and population, their unrestricted release should be absolutely avoided. One particular situation is the core meltdown sequence with steam generator tube rupture (SGTR). The containment bypass turns this sequence into an indispensable scenario to model when assessing PWR risk. As a result, a significant database on the aerosol behavior in the secondary si
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Moskowitz, Steven. "Atomic force miscroscopy [sic] study of SiO₂/Si(111)--(7x7) grown via atomic oxygen plasma /." Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/11556.

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37

Pirani, Parisa. "Surface-Engineered Magnetic Nanoparticles for Sample Preparation and Analysis of Proteins and Peptides." ScholarWorks@UNO, 2015. http://scholarworks.uno.edu/td/2012.

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Sample preparation as an essential step in mass spectrometry-based analysis, plays a critical role in proteomics studies. Magnetic nanoparticles (MNPs) have been widely used in protein and peptide sample preparation due to their magnetic properties, biocompatibility, easy synthesis and surface functionalization. MNPs loaded with analyte or analyte modification reagent can be easily separated from the reaction medium by an externally applied magnetic field. The small size of MNPs provides high analyte loading and extraction capacity. Additionally, MNP can be decorated with different functional
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38

Zbořilová, Zdeňka. "Fotokatalytická aktivita hybridních vrstev oxidu titaničitého a křemičitého." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2013. http://www.nusl.cz/ntk/nusl-216910.

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This diploma thesis is focused on the preparation of hybrid titania-silica layers. Titanium tetraisopropoxide and tetraethyl orthosilicate with Levasil were used as the precursors for TiO2 and SiO2 synthesis, respectively. The layers were deposited on substrates by material printing. Furthermore, this work is focused on study of the photocatalytic activity of prepared titania/silica hybrid layers. Photocatalytic activity of prepared layers was studied by measuring the oxidation of 2,6-dichlorindofenolu, oxidative degradation of stearic acid and oxidation of terephthalic acid. The influence of
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Jakobsson, Lars Klemet. "Distribution of boron between silicon and CaO-SiO2, MgO-SiO2,CaO-MgO-SiO2 and CaO-Al2O3-SiO2 slags at 1600°C." Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for materialteknologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-24010.

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New energy sources are needed for a sustainable future. Solar cells have a huge potential as a sustainable energy source but further development of this technology is needed for solar cells to become cost-competitive with other energy sources. Silicon produced by metallurgical refining methods has the potential of reducing the cost of crystalline silicon solar cells significantly but boron has proven to be hard to remove from silicon by these methods. Slag refining is however a promising refining method for removal of boron from silicon. The aim of this thesis was to determine accurate data fo
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Atik, Mohamed. "La cavitation et ses effets dans la synthèse des matériaux composites (SiO2-SiO2) et (SiO2-SiO2)(B2O3) : étude détaillée du processus du frittage et effets des inclusions rigides." Montpellier 2, 1990. http://www.theses.fr/1990MON20205.

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Synthese des gels composites (sio#2-sio#2) et (sio#2-sio#2) (b#2o#3) a partir des dispersions de teos-aerosil et teos-teb-aerosil par les techniques de sonocatalyse. Mise en forme des materiaux resultants et leur conversion en verre par frittage conventionnel. Le frittage des materiaux composites a ete etudie en detail; notamment l'influence des inclusions sur la cinetique de densification. La croissance des filaments de (nh#4cl) (sio#2) a ete observee au cours du sechage de ces gels composites
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Hung, Kwok-kwong. "Electrical characterization of Si-SiO2 interface for thin oxides /." [Hong Kong : University of Hong Kong], 1987. http://sunzi.lib.hku.hk/hkuto/record.jsp?B12232580.

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洪國光 and Kwok-kwong Hung. "Electrical characterization of Si-SiO2 interface for thin oxides." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1987. http://hub.hku.hk/bib/B31230866.

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43

Veronesi, Michele. "Studio di proprieta ottiche di SiON con simulazioni software." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amslaurea.unibo.it/7778/.

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Il concetto di cella a eterogiunzione in silicio ha portato allo sviluppo di dispositivi in grado di convertire oltre il 25% dello spettro solare. Il raggiungimento di alte efficienze di conversione è dovuto alla ricerca nel campo dei vari strati a base di silicio cristallino, amorfo e nanocristallino impiegati per formare le giunzioni. In particolare, lo studio e l’ottimizzazione dello strato di emettitore in silicio amorfo o nanocristallino insieme all’inserimento di uno strato amorfo intrinseco passivante, ha permesso la realizzazione di celle con alte tensioni di circuito aperto. Questi ma
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Chauvin, Jeanne. "Etude de la Structure et des Propriétés Superficielles et Catalytiques des Systèmes WOx/SiO2 et WOx/Ir/SiO2." Caen, 2013. http://www.theses.fr/2013CAEN2037.

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L’objectif de la thèse est d’arriver à une meilleure compréhension du système bifonctionnel métal acide (WOx/Ir/SiO2) par l’examen des propriétés superficielles et catalytiques de ses composantes métal (Ir/SiO2) et acide (WOx/SiO2). Une série de catalyseurs WOx/SiO2 de teneurs variables en W (0 - 2,4 at. W/nm²) obtenue par calcination à 673 K, a été étudiée par XRD, spectroscopies Raman et UV, adsorption de molécules sondes suivie par spectroscopie infrarouge (FTIR) et par test catalytique. Les résultats indiquent que pour des densités superficielles en W inférieures à 1 atome/nm², le W se tro
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Mackie, Andrew C. "Lecithin-stabilised silica dispersions in non-aqueous media." Thesis, University of Nottingham, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.236022.

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46

Adisty, Dian. "Kinetic Study of SiO2 + SiC Reaction in Silicon Production." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for materialteknologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-22732.

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A number of researches related to kinetics of SiO2 + SiC reaction in the silicon production are limited and there is a gap between the real kinetics and mechanism of SiO2 + SiC reaction and people?s knowledge of that reaction. The main objective of this study was to fill such a gap. In this study, two different types of pellets, i.e. quartz + SiC and cristobalite + SiC (1-2 mm) were used. They were heated up to certain temperature and then held to certain dwell time in an alumina vertical tube furnace (6.28 L) with argon stream of 1L/min. Based on the results of this study, we found that the e
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47

Pozzi, Francesco. "Film di silicon oxinitride (sion) per applicazioni fotovoltaiche, studio di transizioni ottiche." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amslaurea.unibo.it/6686/.

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I materiali per applicazioni fotovoltaiche hanno destato un interesse crescente nella comunità scienti�ca negli ultimi decenni. Le celle HIT (Het- erojunction Intrinsic Thin Layer ) sono dispositivi di ultima generazione che hanno raggiunto e�cienza elevata mantenendo bassi i costi di pro- duzione, e impiegano silicio amorfo (a-Si) come strato emettitore per il suo buon assorbimento della luce e silicio cristallino come regione attiva. La struttura amorfa del silicio presenta però una bassa conducibilità, oltre ad e�etti di degradazione che limitano considerevolmente la durevolezza di u
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Cho, Eun Chel Electrical Engineering UNSW. "Optical transitions in SiO2/crystalline Si/SiO2 quantum wells and nanocrystalline silicon (nc-Si)/SiO2 superlattice fabrication (Restricted for 24 months until Feb. 2006)." Awarded by:University of New South Wales. Electrical Engineering, 2003. http://handle.unsw.edu.au/1959.4/22492.

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Innovation in photovoltaic technology may offer cost competitive options to other energy sources and become a viable solution for the energy and environmental challenges of the 21st century. One proposed innovative technology is based on all-silicon tandem cells, which are constructed using superlattices consisting of environmental friendly Si and its compounds. The well and barrier materials in superlattices are restricted to silicon and silicon oxide during the present study. Single crystalline Si/SiO2 quantum wells (QWs) have been fabricated by thermal oxidation of silicon-on-insulator (SO
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Pecheur, Alexandra. "Élaboration et caractérisation de films de SiO2 déposés à basse température (50°C)." Lyon, INSA, 2000. http://www.theses.fr/2000ISAL0054.

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Ce travail de thèse a eu pour objectif de développer un nouveau procédé industriel de dépôt chimique en phase vapeur assisté par plasma (PECVD) de dioxyde de silicium (Si02) à basse température (50°C). Ce nouveau procédé doit permettre de réaliser la couche d'encapsulation de nouvelles: têtes magnétiques d'écriture-lecture (utilisés dans les disques durs d'ordinateur) réalisées à base de matériau GMR (Giant Magneto-Resistance) et donc très sensibles aux effets thermiques. Après une rapide présentation des têtes magnétiques et des matériaux magnéto résistifs, nous détaillons les problèmes techn
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Li, Bin, and 李斌. "A study of integrated semiconductor thin-film sensors on sio2/si substrate." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B30446752.

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