Carbon Vapor Deposition Cvd
Mostrando 1-12 de 18 artigos, teses e dissertações.
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1. Use of Amphiphilic Composites based on Clay/Carbon Nanofibers as Fillers in UHMWPE
In this work, it is proposed a new strategy to improve the dispersion of inorganic fillers in polymeric matrices by producing surface carbon nanostructures. Clay/carbon nanofibers particles were prepared and used as fillers to improve the mechanical and thermal properties of ultra-high molecular weight polyethylene (UHMWPE). Thermogravimetry (TG), differenti
J. Braz. Chem. Soc.. Publicado em: 2018-02
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2. Catalisadores de Pd metálico modificados por líquidos iônicos para a hidrogenação seletiva de compostos poli-insaturados
In this work, heterogeneous catalysts immobilized on supported ionic liquid (IL) were prepared, characterized and investigated in hydrogenation reactions of the substrates 1,5-cyclooctadiene (1,5-COD), trans-cinnamaldehyde (CALD) and nitrobenzene (NB). Two methods were used to prepare the catalysts. In the first, commercial Pd/C catalyst was coated with diff
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 06/08/2012
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3. Support effect on carbon nanotube growth by methane chemical vapor deposition on cobalt catalysts
A influência do suporte na produção de nanotubos de carbono por deposição química a vapor (CVD) de metano sobre catalisadores de cobalto foi investigada. As técnicas de fisissorção de N2, difratometria de raios X (XRD), redução à temperatura programada (TPR) e quimissorções de H2 e CO foram usadas na caracterização dos catalisadores de cobalt
Journal of the Brazilian Chemical Society. Publicado em: 2012-05
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4. SÃntese de grafeno pelo mÃtodo CVD. / Graphene Synthesis by CVD Method
The advancement and improvement of synthesis techniques and handling of materials are fundamental to understand their properties and possible forms of production and use. However, in the case of nanomaterials, problems such as structural defects, high cost and difficulty of achieving production on a large scale have yet to be solved. Inserted in this panoram
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 16/08/2011
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5. Caracterização por espectroscopia de fotoelétrons de nanotubos de carbono funcionalizados
This work deals with the characterization of functionalized carbon nanotubes, using photoelectron spectroscopy (XPS). The nanotubes are multi-walled nanotubes (MWNT) grown by chemical vapor deposition (CVD) and single-walled nanotubes (SWNT) grown by electric arc discharge. By functionalization we mean the aggregation of functional groups to the walls of the
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 02/06/2011
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6. Sintese de nanotubos de carbono por CVD utilizando catalisadores à base de ferro e molibdênio suportados em matrizes cerâmicas
Molybdenum is known for its synergistic effect in the synthesis of carbon nanotubes (CNs) by chemical vapor deposition (CVD method). When added to typical catalysts like iron, nickel, and cobalt, even in small quantities, it is increases the yield of these nanostructures. The presence of Mo also has an influence on the type and number of CN walls formed. Alt
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 26/02/2010
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7. Sistema RTP: uma técnica poderosa para o monitoramento da formação de nanotubos de carbono durante o processo por deposição de vapor químico
In this work, a TPR (Temperature Programmed Reduction) system is used as a powerful tool to monitor carbon nanotubes production during CVD (Chemical Vapour Deposition), The experiments were carried out using catalyst precursors based on Fe-Mo supported on Al2O3 and methane as carbon source. As methane reacts on the Fe metal surface, carbon is deposited and H
Química Nova. Publicado em: 2010
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8. Estudos da deposição de filmes de diamante CVD sobre carbeto de tungstênio, com interface controlada de boreto / Studies of the deposition of diamond CVD films on tungsten carbide, boride with interface control
The objective of this work was to obtain adherent diamond films on WC-Co substrate through the hot filament assisted CVD technique, using a boriding process to form an intermediate layer and avoid the diffusion of the cobalt to the substrate surface. The boriding process consists of a reactive thermo diffusion treatment, in which boron atoms are spread in th
Publicado em: 2009
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9. Filmes de diamante nanocristalino infiltrados em substratos de silício poroso através das técnicas CVD/CVI / Nanocrystalline diamond films infiltrates in porous silicon substrate by CVD/CVI Processes
The growth of nanocrystalline diamond films (NCD) on porous silicon (PS) substrate was studied using high resolution scanning electron microscopy, high resolution X-ray diffraction, X-ray photoelectron spectroscopy and Raman scattering spectroscopy. The NCD/PS films resulted in a composite material, with great potential for electrochemical application, mainl
Publicado em: 2009
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10. Histological evaluation of the human pulp response to different cavity instrumentation and restorative techniques / Avaliação histológica da resposta pulpar humana a diferentes técnicas de instrumentação cavitária e de restauração
Este estudo se propõe a analisar a resposta pulpar de dentes humanos a preparos cavitários de classe V, em função de duas diferentes técnicas de instrumentação e de duas diferentes técnicas de restauração. Para tal, cavidades classe V, nas superfícies vestibulares de 48 pré-molares hígidos de pacientes entre 11 e 25 anos, que estavam em tratamen
Publicado em: 2009
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11. Carbon nanofibers: a versatile catalytic support
The aim of this article is present an overview of the promising results obtained while using carbon nanofibers based composites as catalyst support for different practical applications: hydrazine decomposition, styrene synthesis, direct oxidation of H2S into elementary sulfur and as fuel-cell electrodes. We have also discussed some prospects of the use of th
Materials Research. Publicado em: 2008-09
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12. Contribuições ao desenvolvimento de filmes de diamante microcristalino dopados com enxofre / Contributions to the development of sulphur doped microcrystalline diamond films
We present in this work the development of grown diamond films with sulphur addition. They had been grown by chemical deposition from the vapor phase (diamond CVD) using reactors of the type hot filament. For the diamond attainment with conduction of the n-type, we diluted different concentrations of carbon disulfide (CS2) in ethyl alcohol, whose vapor was d
Publicado em: 2007