Carbon Nitride
Mostrando 1-12 de 23 artigos, teses e dissertações.
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1. Assessment of Reaction Parameters in the Polymeric Carbon Nitride Thermal Synthesis and the Influence in Photocatalytic Hydrogen Production
In this work, the reaction parameters for polymeric carbon nitride synthesis by thermal polycondensation were assessed, such as type of precursor, heating rate and time of thermal treatment, in order to obtain crystalline materials with high photocatalytic performance. All synthesized materials were tested as photocatalysts in hydrogen production using ethyl
J. Braz. Chem. Soc.. Publicado em: 2020-05
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2. Avaliação dos processos de fratura em filmes finos através da simulação de ensaios de indentação com penetradores esféricos
RESUMO Recentes trabalhos propõem a utilização dos ensaios de indentação como uma ferramenta capaz de avaliar características mecânicas de filmes finos, assim como avaliar possíveis falhas em sistemas que conjugam filmes de alta dureza depositados em substratos metálicos em solicitações tribológicas. Entretanto, a implementação da técnica de i
Matéria (Rio J.). Publicado em: 25/11/2019
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3. Characterization of Different Surface Layers Produced by Solid Boron-Nitro-Carburizing Thermochemical Treatment on AISI 1020
The aim of this study is to obtain and characterize surface layers on low carbon steel with the pack boron-nitro-carburizing process. Different mixtures of commercial powders (Turbonit® and Ekabor®) were used to investigate the case properties, microstructure and phases formation on AISI 1020 steel. A series of experiments were conducted in solid medium wi
Mat. Res.. Publicado em: 04/11/2019
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4. Dependence of Wear and Mechanical Behavior of Nitrocarburized/CrN/DLC Layer on Film Thickness
Diamond-like carbon (DLC) films are amorphous metastable carbon form that provide interesting mechanical and tribological properties. The role of film thickness influence upon wear and mechanical properties is of interest and not yet fully reported. In this study, two samples of previously plasma nitrocarburized, quenched and tempered H13 steel were duplex t
Mat. Res.. Publicado em: 31/01/2019
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5. Fatiga de contacto por rodadura en acero SAE 1050 recubierto con TiN, posteriormente templado
ABSTRACT The use of ceramic coatings of the nitride, carbide, or diamond type on steel substrates promotes the improvement of tribology properties. Nevertheless, high hardness gradients and adhesion problems may deteriorate the performance of these coatings when subjected to Rolling Contact Fatigue (RCF). Some studies on steels with ceramic coatings were car
Matéria (Rio J.). Publicado em: 19/07/2018
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6. Finite Element Modeling and Experimental Verification of Nitriding Process in S30C Steel
A mathematical model has been developed to simulate the nitriding process of plain carbon steel, considering the simultaneous diffusion of nitrogen in different iron-nitrogen (Fe-N) phases and the precipitation dynamics of γ' and ε iron-nitride. The model can predict the distribution of nitrogen concentration, volume fraction of Fe-N phases and hardness. F
Mat. Res.. Publicado em: 16/02/2017
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7. Effects of Different Plasma Nitrided Layers on the Tribological Performance of DLC Coatings
When multifunctional surface engineering processes that combine purpose-oriented phases are applied to soft substrates, a combination of high wear resistance, high load support and low coefficients of friction can be achieved. In this study, the effects of different nitrided layers on the tribological behaviour of a diamond-like carbon (DLC) film deposited o
Mat. Res.. Publicado em: 12/09/2016
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8. Methods of data analysis for the ball cratering test on TiN and DLC coated steel
Titanium nitride (TiN) coatings are widely used in machining because of its mechanical characteristics which modify the surface of the substrate increasing the capacity of load support and reduction of friction, while a coating as diamond-like carbon (DLC), which also has interesting mechanical properties, needs better attention. In this sense, the developme
Mat. Res.. Publicado em: 05/02/2016
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9. XPS, XRD and laser raman analysis of surface modified of 6150 steel substrates for the deposition of thick and adherent diamond-like carbon coatings
Although the 6150 steel has an excellent fatigue and impact resistance, it is unsuitable to operate it when the corrosion is a limited factor. We propose here a sequence of steel pre-treatment by carburizing, carbonitriding and nitriding in order to improve the poor adhesion between Diamond Like-Carbon coatings on steel. This sequence is our attempt to reduc
Mat. Res.. Publicado em: 25/02/2013
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10. Estudo da influência de substratos de TiN no crescimento de nanotubos de carbono / Study of the influence of TiN substrates on the carbon nanotubes growth
Dado o interesse nas propriedades e aplicações dos nanotubos de carbono devidas às suas características morfológicas, este trabalho tem como objetivo principal o estudo da influência do substrato no crescimento dos nanotubos de carbono. Com este objetivo em mente foram preparados filmes de nitreto de titânio, com o intuito de ser usados como suporte p
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 14/12/2011
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11. Conformational analysis and electronic structure of chiral carbon and carbon nitride nanotubes
Geometry and electronic structure of chiral carbon and carbon nitride (CNx) nanotubes were investigated through quantum chemical methods. Finite nanotubes with diameters ranging from 5 to 10 Å and containing up to 500 atoms were considered. CNx structures were built through random substitution of carbon atoms by nitrogen. The molecules were fully optimized
Materials Research. Publicado em: 30/09/2011
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12. Nanorolos de nitreto de boro : um estudo por dinamica molecular classica / Boron nitride nanoscrolls : a classical molecular dynamics study
In this work we report a study about the structural and dynamical properties of boron nitride nanoscrolls (BNNSs). BNNSs are nanostructures formed by rolling up boron nitride (BN) sheets into a spiral(papyrus)-like format. Although carbon nanoscrolls (CNSs) have been observed experimentally synthesized using different techniques, up to this moment no experim
Publicado em: 2010