Ferrites Spinel
Mostrando 1-12 de 17 artigos, teses e dissertações.
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1. Influence of the Local Structure on the Photocatalytic Properties of Zinc Spinel Ferrite Nanoparticles
The correlation between iron distribution in octahedral or tetrahedral sites in synthetic magnetite and zinc spinel ferrites and their catalytic properties were investigated in this work. The zinc-doped nanomagnetites were prepared by co-precipitation method and annealed at 420 °C. X-ray diffraction, UV-Vis, X-ray absorption and 57Fe Mössbauer spectroscopi
Journal of the Brazilian Chemical Society. Publicado em: 2022
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2. Ferrimagnetic to paramagnetic transition and dielectric relaxation in Ni1-xZnxFe2O4 ferrites
Abstract The spinel ferrite system Ni1-xZnxFe2O4 (x=0-0.7, Δx=0.1) was prepared by wet chemical co-precipitation method using sulfates of respective metal ions. The electrical resistivity and dielectric properties of the prepared samples have been studied as a function of temperature, frequency, and Zn content (x). The DC resistivity (ϱ) was measured in th
Cerâmica. Publicado em: 2021-06
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3. Obtenção de ferritas de cálcio dopadas com cromo visando aplicação em esmaltes transparentes brilhante e mate
RESUMO Este trabalho tem como objetivo obter óxidos com estrutura tipo espinélio de composição CaFe1,8Cr0,2O4 pelo método gelatina, visando aplicação em esmaltes transparentes brilhantes e mate. Os pós precursores, resultantes do processo de síntese, foram calcinados a 600 °C e a 800 °C para a obtenção da fase espinélio. Os pós foram caracteri
Matéria (Rio J.). Publicado em: 25/11/2019
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4. Nanoparticles of Ni1-x Znx Fe2 O4 used as Microwave Absorbers in the X-band
Ferrites nanoparticles of Ni1-xZnxFe2O4 ferrites with x varying between 0 and 1, in steps of 0.2, were obtained by solution combustion synthesis (SCS) and dispersed in oil paint at the concentrations of 10, 20, 30 and 40% by ferrite weight of ferrite, with the aim of producing electromagnetic wave absorbing composites, in the X band (8-12 GHz). The ferrite p
Mat. Res.. Publicado em: 21/10/2019
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5. Síntesis y estudio de propiedades estructurales y magnéticas de ferritas Mg1-xZnxFe2O4 (x= 0-0,9)
ABSTRACT Nowadays, iron oxide based magnetic nanoparticles are used in several science and technology applications due to their magnetic properties. Likewise, these materials are used in biomedical applications such as contrast agents for magnetic resonance imaging, magnetic hyperthermia, targeted drug delivery, etc. In this work, the synthesis and character
Matéria (Rio J.). Publicado em: 19/07/2018
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6. Transport Properties of Polycrystalline Mixed Copper-Zinc Ferrites
Polycrystalline mixed Cu-Zn spinel ferrites with general formula Cu1-xZnxFe2O4 (x = 0.0, 0.1, 0.3, 0.5 and 0.7) have been prepared by solid-state reaction method. The effect of Zn2+ ions on transport properties such as DC and AC resistivity, dielectric constant and dielectric loss tangent has been presented in this paper. The resistivity increases with Zn co
Mat. Res.. Publicado em: 19/04/2018
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7. Tunable Magnetic and Electrical Properties of Cobalt and Zinc Ferrites CO1-XZnXFe2O4 Synthesized by Combustion Route
Co and Zn ferrites with general formula CO1-XZnXFe2O4 (x = 0; 0,2 and 0,8) were synthesized by combustion reaction method, using urea as fuel. The structure of inverse-spinel-type ferrite were characterized through XRD using Rietveld refinement method to identify, quantify phases and determine lattice parameters. The crystallites had mean size of 37,33 nm, 4
Mat. Res.. Publicado em: 12/03/2018
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8. Microwave Assisted Combustion Synthesis and Characterization of Nanocrystalline Nickel-doped Cobalt Ferrites
Abstract Nanoparticles nickel-doped cobalt ferrites [NixCo1-xFe2O4 (x = 0.0, 0.25, 0.50, 0.75 and 1.0 of Ni2+)] were prepared by the microwave combustion synthesis, using a stoichiometric mixture of metal nitrates and urea as the oxidizer and fuel to drive the reaction. The effect of microwave irradiation on the phase composition was favorable to promote the
Mat. Res.. Publicado em: 01/08/2016
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9. Magnetic and Electrical Properties of MnxCu1-xFe2O4 Ferrite
In the present work, mixed manganese-copper ferrite of composition MnxCu1-xFe2O4 (within x=0.40, 0.42, 0.44, 0.46, 0.48 and 0.50) have been investigated for their electric and magnetic properties such as dc resistivity, Curie temperature, saturation magnetization. MnxCu1-xFe2O4 ferrite samples were prepared by uniaxial pressing from the oxide mixture, synthe
Mat. Res.. Publicado em: 31/05/2016
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10. Structural and Magnetic Properties of Hydrothermal Spinel Ni0.4Zn0.6Fe2O4 Ferrites
Spinel ferrite powder with a nominal composition Ni0.4Zn0.6Fe2O4 was prepared by a hydrothermal method, following by sintering at 700 °C and 900 °C, respectively. The structural and magnetic properties of specimens are studied. It is found that the large particles in specimens are the agglomerates of many small nanoscale crystallites. A strengthening of ch
Mat. Res.. Publicado em: 17/11/2015
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11. Ferritas de cobre e zinco do tipo espinélio sintetizadas pelos métodos: hidrotermal assistido por micro-ondas, precursores poliméricos, reação no estado sólido e decomposição térmica / Spinel type copper and zinc ferrites synthesized by the methods: microwave assisted hydrothermal, polymeric precursor, solid state reaction and thermal decomposition.
Ferrites are well studied materials due to their wide application as: gas detector, optical, electronic and magnetic devices, catalyst and pigments. In the synthesis of materials, the properties are extremely influenced by the synthesis method. In this work, four methods were used in the synthesis of spinel ferrites with composition Zn1-xCuxFe2O4 (x = 0,0; 0
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 05/05/2012
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12. Influence of the sintering temperature on the magnetic and electric properties of NiFe2O4 ferrites
This study evaluates the structural, microstructural, electric and magnetic properties of nickel ferrite samples prepared through the solid state reaction. It was observed that an increase in the sintering temperature produces a higher cation concentration in the A site when compared to the B site. The assessment of magnetic properties showed that an increas
Materials Research. Publicado em: 08/05/2012