Amorphous Carbon
Mostrando 25-36 de 83 artigos, teses e dissertações.
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25. Nanocompositos de poli(3-hidroxibutirato-co-3-hidroxivalerato) e nanotubos de carbono / Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) carbon nanotubes nanocomposites
This work has evaluated the effect of addition of multi walled carbon nanotubes (NTC) in the thermal and mechanical properties, morphology and hydrophobicity of poly(3-hydroxybutyrate-co-3-hydroxyvalerate), the PHBV. The addition of carbon nanotubes could result in an improvement of PHBV properties, a natural polyester that due to its biodegradability and bi
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 11/06/2010
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26. Isótopos de carbono em filitos carbonosos da sequência metavulcano-sedimentar Marmeleiro, Sul de Ibaré, Rio Grande do Sul
Carbon isotope ratios for carbonaceous material in the graphite prospect of Marmeleiro Sequence, southwestern of the Sul-rio-grandense Shield, have been determined. The results are approximately constant with d13C-values between -27 and -24 per mil. These values suggest that the studied carbonaceous rocks were formed from syngenetic organic detritus, which w
Publicado em: 2010
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27. Study of optical and electro-optical properties of diamond-like carbon films - DLC. / Estudo das propriedades ópticas e eletro-ópticas de filmes de carbono amorfo tipo diamante - DLC.
In this work it was studied electrical and optical characteristics of diamond-like carbon (DLC) films deposited in a reactive RF magnetron sputtering system on silicon and glass substrates. Samples were deposited at different process conditions in each type of substrate at two pressure conditions (5 mTorr and 10 mTorr) and four conditions of RF power (100 W,
Publicado em: 2010
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28. Camadas antirrefletoras de carbono amorfo e carbeto de silicio para celulas solares de silicio cristalino / Antireflective coatings of amorphous carbon and silicon for crystalline silicon solar cells
Nesta tese estamos propondo o uso de carbono amorfo como um possível candidato para uso como camada antirrefletora em células solares de silício cristalino. O carbono amorfo pode ser preparado com alta banda proibida e tem propriedades importantes como alta dureza, baixo coeficiente de atrito, preparado à temperatura ambiente, etc. Além disso, o carbono
Publicado em: 2009
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29. Optical, mechanical and structural properties of amorphous carbon films / Propriedades opticas, mecanicas e estruturais de filmes de carbono amorfo
Neste trabalho desenvolvemos um sistema de deposição de filmes finos pela técnica de arco catódico filtrado (FCVA- Filtered Cathodic Vacuum Arc), que possibilita o desenvolvimento de ligas metálicas e, sobretudo, a deposição de filmes de carbono amorfo altamente tetraédrico. Utilizando este sistema desenvolvemos filmes de carbono amorfo (a-C) com ele
Publicado em: 2009
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30. Estudo e aplicação das propriedades elétricas, térmicas e mecânicas de materiais amorfos piezoresistivos em transdutores de pressão. / Study and application of eletrical properties, thermal and mechanical of amorphus matherials in piezoresistive.
This tesis presents the piezoresistivity theoretical and experimental study for two materials with amorphous structure. The first material is the Diamond Like Carbon and the other is the Indium Tin Oxide. The work includes the bibliographic study, theoretical and practical design of structures for testing individual and piezoresistors configured in bridge, i
Publicado em: 2009
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31. UtilizaÃÃo da serragem de Eucalyptus sp. na preparaÃÃo de carvÃes ativados / Utilization of sawdust of Eucalyptus sp. for activated carbons preparation
The aim of this study was to use the eucalyptus sawdust, waste timber industry, in the preparation of activated carbons (AC) and test them as adsorbents of organic compounds and metal ions. Initially, the Eucalyptus sp sawdust was characterized by chemical analysis like cellulose, lignin, hemicelluloses, ash and extractives content as well as some instrument
Publicado em: 2009
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32. Purificação e caracterização de nanotubos de carbono produzidos pelo método de descarga em arco elétrico
The objective of this work was to study the purification of a sample of commercial carbon nanotubes (CNTs) produced by the Carbolex arc-discharge method using the catalyst mixture Ni/Y (4/1 at. %). Another objective of this work was to investigate an alternative functionalization route for the introduction of hydroxyl groups (-OH) onto CNT sidewalls and to e
Publicado em: 2008
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33. Estrutura eletronica de precursores de alomelaninas / Electronic structure of allomelanins precursors
In this work we studied, on the basis of a semiempirical and ab initio approaches, the structure and electronic properties of some allomelanins precursors. Allomelanins are part of an ubiquitous class of dark pigments known as melanins and their precursors are formed by monomers of catechol and o-benzoquinone units. Due to the lack of extensive experimental
Publicado em: 2008
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34. Development of a reactor for growth of diamond tubular films / Desenvolvimento de um reator para o crescimento de filmes diamantiferos tubulares
A hot-filament chemical vapor deposition system was designed and built to grow diamond thin films. This system fed with ethanol highly diluted in hydrogen was employed to deposited diamond layers onto quartz tubes with diameters of 6 mm and length of 10 cm. High uniformity microcrystalline diamond films were obtained thanks the maintenance of the substrate i
Publicado em: 2008
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35. DLC with silver nanoparticles study for space and biomedical applications / Estudo de crescimentos de filmes de DLC com nanopartículas de prata para aplicações espaciais e biomédicas
Diamond-like carbon (DLC) is a metastable form of amorphous carbon with high mechanical hardness, chemical inertness, optical transparency, low friction coefficient and its wear resistant. Since centuries, silver is known as bactericidal agent and, as a soft metal, its also used as a solid lubricant. This project develops a deposition process to insert silve
Publicado em: 2008
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36. Material carbono ceramico condutor SiO2/ZrO2/C-grafite : sintese, caracterização e aplicações / SiO2/ZrO2/C-graphite conducting carbon ceramic material : synthesi characterization and application
SiO2/ZrO2/C-graphite was prepared by the sol-gel method in two compositions: (A) SZC30 (SiO2 = 50 %, ZrO2 = 20 %, C = 30 %) e (B) SZC20 (SiO2 = 60 %, ZrO2 = 20 %, C = 20 %) in % m/m, characterized and used to prepare electrodes. The carbon ceramic material was thermally treated at 400, 600, 800 and 1000 °C in nitrogen atmosphere, and it was observed that it
Publicado em: 2008