Polysiloxane
Mostrando 1-12 de 31 artigos, teses e dissertações.
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1. Effect of techniques, trays and materials on accuracy of impressions clinically made
Resumo Introdução Realizar moldagens precisas e dimensionalmente estáveis que dupliquem a condição oral é um passo essencial para a confecção de restaurações indiretas de qualidade, garantindo seu sucesso e longevidade. Diversos estudos tem demonstrado os prós e contras de diferentes técnicas de moldagem, mas nenhum consenso da melhor técnica a
Rev. odontol. UNESP. Publicado em: 23/09/2019
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2. Polydimethylsiloxane as a Matrix for the Stabilization and Immobilization of Zero-Valent Iron Nanoparticles. Applications to Dehalogenation of Environmentally Deleterious Molecules
A wet-synthetic method is described to obtain magnetic, air-stable, zero-valent iron nanoparticles coated with an alkanedioic acid. The particles can be immobilized in an amino-substituted polysiloxane matrix to provide materials capable of dechlorinating, debrominating, and deiodinating a wide variety of halogenated organic molecules dissolved initially in
J. Braz. Chem. Soc.. Publicado em: 2018-07
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3. SÍNTESE ENZIMÁTICA DO CAPRILATO DE ISOPENTILA UTILIZANDO ÓLEO FÚSEL COMO MATÉRIA-PRIMA
Four commercial lipase preparations immobilized by covalent attachment on epoxy-polysiloxane-β-cyclodextrin were tested as potential biocatalysts to mediate the esterification reaction of isopentanol with caprylic acid in solvent-free medium. Among them, the immobilized lipase from Rhizopus oryzae was the most active biocatalyst, attained ester conversion h
Quím. Nova. Publicado em: 2017-06
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4. Self-Immobilization of Poly(methyltetradecylsiloxane) onto Metalized Silica Particles as Stationary Phases for HPLC
This work presents a study of the sorption of a pre-synthesized polysiloxane, poly(methyltetradecylsiloxane) - PMTDS, onto zirconized and titanized-silica particles that results in efficient stationary phases for reversed phase liquid chromatography. The sorbed materials, after 6 days at room temperature without any chemical or physical agent, denominated as
J. Braz. Chem. Soc.. Publicado em: 2016-06
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5. Influence of different fillers on the properties of an experimental vinyl polysiloxane
Abstract The aim of the study was to evaluate the effect of the incorporation of different fillers on an experimental vinyl polysiloxane (VPS) at two different concentrations, 20% and 40%. Different fillers were added to an experimental VPS. The study was developed in two stages: (i) incorporation of fillers in different concentrations: (a) 20 wt% fillers, a
Braz. oral res.. Publicado em: 28/03/2016
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6. Porous ceramic materials from polysiloxane-clay composites
Este trabalho descreve as alterações estruturais, texturais e morfológicas de cerâmicas porosas derivadas de polímeros e obtidas pela pirólise de compósitos polissiloxano/argila, contendo formador de poros à base de poli(dimetilsiloxano) e acetato de níquel como indutor de nanoestruturas. Os compósitos foram obtidos a partir de molde de aço-inox,
J. Braz. Chem. Soc.. Publicado em: 2014-04
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7. Cromatografia gasosa quiral na resolução de enantiômeros envolvidos em flavours de frutas
This work addresses the use of chiral gas chromatography in resolving optically active stereoisomers and racemates found in fruit flavours. It presents the types of chiral selectors applied to terpene-derived metal coordination compounds, polysiloxane-linked α-amino acid and mixed chiral stationary phases, and focuses on derivatized cyclodextrins, the most
Quím. Nova. Publicado em: 2014
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8. Preparação, caracterização e aplicação de fases estacionárias tipo C8 modificadas por óxidos metálicos para cromatografia líquida
This work describes three C8-stationary phases for high performance liquid chromatography based on silica metallized with ZrO2, TiO2 or Al2O3 layers, having poly(methyloctylsiloxane) immobilized onto their surfaces. The stationary phases were characterized using XRF, XAS, FTIR, SEM and elemental analysis to determine the physical characteristics of the oxide
Quím. Nova. Publicado em: 2013
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9. Comportamento das forças de adesão do adesivo selante de silicone e do mastic butílico sob o efeito da radiação ionizante. / Behavior of the adhesion forces of silicone adhesive sealant and butyl mastic after the exposure to ionizing radiation.
Adhesives are products that can keep materials together by bonds between the surfaces. Sealants are products that can keep filled a space between two surfaces, through a barrier that is configured as a \"bridge\" between the two surfaces. The mastic is a product made of a mixture of substances with the primary butyl polymer, with the consistency of a mass no
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 15/12/2011
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10. Fases estacionárias para cromatografia líquida de alta eficiência em fase reversa por imobilização térmica do poli(2-fenilpropil) metilsiloxano sobre sílica / Stationary phases for reversed-phase high-performance liquid chromatography using thermal immobilization of poly (phenylpropyl) methylsiloxane onto silica
Este trabalho apresenta o desenvolvimento de fases estacionárias (FE) para utilização em Cromatografia Líquida de Alta Eficiência em Fase Reversa (CLAE-FR) a partir da imobilização térmica de poli (2-fenilpropil) metilsiloxano (PFPMS) sobre suporte de sílica. Diferentes quantidades de copolímero foram avaliadas, alcançando-se um bom desempenho cro
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 01/03/2011
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11. Enzymatic route selection for monoglyceride production using immobilized lipase on matrix obtained by sol-gel technique / Estratégias para desenvolvimento de um sistema operacional eficiente para a produção enzimática de monoglicerídeos
The objective of this project was to select the best enzymatic route to produce monoglycerides using lipase immobilized on matrix obtained by sol-gel technique, aiming to contribute for a better utilization of the glycerol generated as by-product in the biodiesel synthesis. For this purpose two methodologies were analyzed: (1) direct esterification of the gl
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 13/11/2009
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12. Alternativa potencial para aproveitamento do glicerol gerado na produção de biodiesel: síntese enzimática de monolaurina por esterificação
Esterification reactions of glycerol with lauric acid in solvent free system were carried out using lipases from several sources. All lipases were immobilized on polysiloxane-polyvinyl alcohol particles by covalent binding with high activity recovered. Among the tested enzymes, the Candida antarctica lipase allowed to attain the highest molar conversion (76%
Química Nova. Publicado em: 2009