Pechini
Mostrando 13-24 de 143 artigos, teses e dissertações.
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13. Morphological Characterization of Tungsten Trioxide Nanopowders Synthesized by Sol-Gel Modified Pechini's Method
Sol-gel modified Pechini's method was used to prepare WO3 nanopowders using dicarboxylic acid and polyethylene glycol as the chelating agent and polymeric source, respectively. WO3 powders were first prepared by calcination of resin precursor at 550ºC under various initial concentrations of metal ion (12.5-50 mmol), acid (125-500 mmol), a complexing agent (
Mat. Res.. Publicado em: 28/09/2017
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14. Avaliação da fotoluminescência do TiO 2 sintetizado pelo método Pechini
Resumo Um material que se destaca para uso em várias aplicações é o dióxido de titânio (TiO2), devido principalmente às suas propriedades de estabilidade térmica e química e as suas excelentes propriedades ópticas. Porém, estas propriedades são dependentes do tipo de fase e da característica morfológica, o que está diretamente relacionado com
Cerâmica. Publicado em: 2017-09
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15. Sinterização ultrarrápida por micro-ondas de compósitos particulados PZT/FCO preparados por mistura em ultrassom
Resumo Pós de Pb(Zr0,53Ti0,47)O3 (PZT) e Fe2CoO4 (FCO), foram sintetizados separadamente pelo método Pechini e misturados em ultrassom, nas proporções molares 80/20 e 50/50 (PZT/FCO). Os compósitos preparados foram prensados e submetidos à sinterização em forno convencional e sinterização ultrarrápida assistida por micro-ondas. A caracterização
Cerâmica. Publicado em: 2017-09
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16. Effect of Fe3+ Doping in the Photocatalytic Properties of BaSnO3 Perovskite
In the last ten years, stannates with perovskite structure have been tested as photocatalysts. In spite of the ability of perovskite materials to accommodate different cations in its structure, evaluation of doped stannates is not a common task in the photocatalysis area. In this work, Fe3+ doped BaSnO3 was synthesized by the modified Pechini method, with ca
Mat. Res.. Publicado em: 10/08/2017
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17. Effect of La Doping on the Crystal Structure, Electric, Magnetic and Morphologic Properties of the BSCCO System
Studies of the doping process can provide a better understanding of the superconducting mechanisms in cuprous oxide materials. In this work, we studied the doping effects on the crystal structure, electric, morphologic and magnetic properties of the BSCCO system with the nominal composition Bi1.6Pb0.4Sr(2-x)RExCa2Cu3O(10-δ). Here, the rare earth element (RE
Mat. Res.. Publicado em: 03/08/2017
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18. Structure and Physical Properties of the LaBiFe2O6 Perovskite Produced by the Modified Pechini Method
In this paper the synthesis of the LaBiFe2O6 material by the modified Pechini method is reported. Structural, morphologic, magnetic and optic experimental studies were performed. Rietveld refinement of x-ray diffraction patterns revealed that LaBiFe2O6 crystallizes in an orthorhombic perovskite structure (space group Pnma, # 62). Scanning electron microscopy
Mat. Res.. Publicado em: 24/07/2017
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19. Nanoparticles of ZnO Doped With Mn: Structural and Morphological Characteristics
In this study, the effects of dopant concentrations on the structural and morphological characteristics of Zn1-xMnxO powders (x= 0.025, 0.05, 0.075, and 0.1 mole) synthesized by the Pechini method has been investigated. The powder was characterized by X-ray diffraction (XRD), Brunauer-Emmet-Teller (BET) specific surface, energy dispersive X-ray (EDX), scanni
Mat. Res.. Publicado em: 08/06/2017
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20. ZnO puro e dopado com Al obtidos pelo método Pechini-modificado aplicado na transesterificação etanólica do óleo de algodão
Resumo Óxido de zinco puro (ZnO) e dopado com 5% de Al (ZNAL) foram sintetizados pelo método Pechini modificado e caracterizados por difração de raios X (DRX), fluorescência de raios X (FRX), espectroscopia Raman, espectroscopia no infravermelho e espectroscopia UV-visível. A análise por FRX confirmou a relação estequiométrica teórica, enquanto DR
Cerâmica. Publicado em: 2017-03
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21. DEGRADAÇÃO FOTOCATALÍTICA DE ATRAZINA NA PRESENÇA DE CATALISADORES NANOPARTICULADOS
Atrazine is a persistent herbicide and several studies have detected their presence in drinking water sources. In this work the atrazine photocatalytic degradation was investigated in aqueous solution using TiO2, ZnO and TiO2/ZnO catalysts. The catalysts were synthesized by Pechini's method and characterized by X-ray diffraction (XRD) and scanning electron m
Quím. Nova. Publicado em: 2017-01
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22. 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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23. Síntese de Filmes de LiNbO 3 Utilizando Oxalato Amoniacal de Nióbio
RESUMO Neste trabalho, investigamos o processo de preparação de filmes finos de niobato de lítio (LiNbO3), utilizando como fonte de Nióbio (Nb) o Oxalato Amoniacal de Nióbio (NH4H2NbO(C2O4).3H2O, na síntese da resina precursora pelo método dos precursores poliméricos (Pechini). A cinética de formação de fase foi investigada com base nos padrões d
Matéria (Rio J.). Publicado em: 2016-09
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24. Spectroscopic Properties of pigment Li2-xZn1-xPrxTi3O8
Inorganic compounds doped with rare earths (Ce3+, Pr3+, Nd3+, Sm3+, Eu 3+, Gd 3+, Tb 3+, Tm3+) have been used in various applications including light-emitting devices such as fluorescent lamps, cathode ray tubes, lasers and inorganic pigments. In this study, Pr3+ is doped in spinel Li2ZnTi3O8 system and synthesized by the polymeric precursor method, which is
Mat. Res.. Publicado em: 14/06/2016