Niobium Pentoxide
Mostrando 1-11 de 11 artigos, teses e dissertações.
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1. Development of a microwave absorbing material based on molybdenum-doped niobium pentoxide
Abstract This work aimed to perform the characterization of electrical properties of niobium pentoxide, Nb2O5, pure and doped with molybdenum, prepared by powder metallurgy route and to do a comparative analysis of the influence of this material when sintered in a muffle or in a microwave oven. The results showed that the doping of the niobium pentoxide with
Cerâmica. Publicado em: 2019-01
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2. Synthesis and Structural Properties of Niobium Pentoxide Powders: A Comparative Study of the Growth Process
Powders Nb2 O5 were prepared by two different synthesis method, Sol-Gel and polymeric precursors (Pechini). In the Pechini method before adding the citric acid in the process, four different solutions were used to get the samples. For Sol-gel method, two different processes were also used in obtaining powders. The precursor was completely solubilized in etha
Mat. Res.. Publicado em: 10/10/2016
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3. ÓXIDOS DE NIÓBIO: UMA VISÃO SOBRE A SÍNTESE DO Nb2O5 E SUA APLICAÇÃO EM FOTOCATÁLISE HETEROGÊNEA
Despite the fact that Brazil is the world’s largest niobium mineral producer, governmental interest in exploration of the mineral leading to more valuable derived materials is scarce, which has reduced the country’s knowledge about a wider range of technological applications for this metal. Niobium pentoxide stands out due its remarkable electronic, stru
Quím. Nova. Publicado em: 2015-01
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4. Niobium pentoxide coating replacing zinc phosphate coating
A new coating made of niobium pentoxide, obtained through the sol-gel process, was developed for the carbon steel (SAE 1010). The corrosion protection provided by this coating was evaluated through electrochemical tests such as: open circuit potential, electrochemical impedance spectroscopy and anodic potentiodynamic polarization in NaCl 0,5 mol L-1 solution
Matéria (Rio J.). Publicado em: 2014-06
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5. Characterization of ZSM-5 modified with niobium pentoxide: the study of thiophene adsorption
Adsorventes ZSM-5 impregnados com Nb2O5 foram aplicados na remoção de enxofre sob a forma de tiofeno, substância refratária de difícil remoção dos combustíveis líquidos. Para tanto, foi preparado um combustível modelo contendo iso-octano contaminado com tiofeno nas concentrações de 877,5 a 1155 ppmw. As amostras foram caracterizadas por difratome
J. Braz. Chem. Soc.. Publicado em: 2013-01
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6. Study of the aluminothermic reduction of niobium pentoxide through thermal analysis experiments and high energy milling processing
Aluminothermic reduction of niobium pentoxide was studied through thermal analysis techniques such as differential thermal analysis (DTA) and thermogravimetry (TG) as well as through high energy milling processing. Reactants mixtures were composed by powders of Nb2O5 and Al. In the case of DTA-TG experiments, different molar ratios Nb2O5:Al were heated in a
Materials Research. Publicado em: 2007-06
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7. The thermal decomposition of monohydrated ammonium oxotris (oxalate) niobate
The thermal decomposition in argon of the monohydrated ammonium tris(oxalate)niobate, (NH4)3NbO(C2O4)3.H 2O, has been studied by TG/DTG, DTA, DSC, IR absorption and XRD. The material decomposes stepwise by the release of CO, CO2, NH3 and water. The atomic structure of the complex initially becomes amorphous and then crystallizes twice in the form of orthorho
Brazilian Journal of Chemical Engineering. Publicado em: 2006-12
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8. Obtenção de pós de Nb a partir da redução aluminotérmica com ignição por plasma
The aluminothermic reduction consists in an exothermic reaction between a metallic oxide and aluminum to produce the metal and the scum. The extracted melted metal of that reaction usually comes mixed with particles of Al2O3 resulting of the reduction, needing of subsequent refine to eliminate the residual impure as well as to eliminate porosities. Seeking t
Publicado em: 2005
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9. Niobium carbide synthesis by solid-gas reaction using a rotating cylinder reactor
A rotating cylinder reactor was designed for the synthesis of niobium carbide powders at 1173 K. Niobium carbide, NbC, was prepared by carbothermal reduction starting from commercial niobium pentoxide powders. The reactor was heated using a custom-made, two-part, hinged, electric furnace with programmable temperature control. The design and operational detai
Brazilian Journal of Chemical Engineering. Publicado em: 2004-09
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10. Evaluation of Nb2O5 and Ag/Nb2O5 in the photocatalytic degradation of dyes from textile industries
The textile industries are distinguished by the use of dyes that are applied to textiles. Dyes are pollutant materials that are difficult to decompose by microbiological treatment. An alternative way to prevent contamination of the environment by dyes is the oxidation of these materials through photocatalysis, a process by which illumination of an oxide semi
Brazilian Journal of Chemical Engineering. Publicado em: 2002-12
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11. Preparation and characterization of thin films of Nb2O5 doped with Li+ for possible architecture applications. / Preparação e caracterização de filmes finos sol-gel de Nb2O5 dopados com Li+ visando possível aplicação em arquitetura.
O presente trabalho consiste na preparação e caracterização de filmes finos de óxido nióbio (Nb2O5) dopados com trifluoro metano sulfonato de lítio (CF3SO3Li). A adição do sal de lítio tem como objetivo verificar a influência do mesmo nas performances opto-eletroquímicas dos filmes de óxido de nióbio. Os sóis para deposição dos filmes foram
Publicado em: 2001