Ferrites
Mostrando 1-12 de 41 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. The Influence of Isothermal Holding Times on Microstructural Evolution of X90 Linepipe Steel
Microstructural phase of linepipe steels depends on different isothermal conditions. Thermal cycling testing of X90 linepipe steel was conducted using a thermomechanical simulator. The results have shown that with increased holding time, the microstructure constituents change from the martensite and bainitic ferrites to granular bainite and polygonal ferrite
Mat. Res.. Publicado em: 28/03/2019
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6. 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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7. 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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8. 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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9. Mechanical, Magnetic, and Microstructural Characterization of Ni0.9Co0.1Fe2O4 Produced by the Ceramic Method
Ni-Co ferrites, especially the ones with lower cobalt fractions, are candidate materials for applications in magnetomechanical sensors and electromagnetic wave absorbers. This work studied the microstructure, magnetostriction, flexural strength, and complex magnetic permeability of Ni0.9Co0.1Fe2O4, presenting data that weren't covered by previous literature
Mat. Res.. Publicado em: 22/02/2018
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10. Synthesis and Characterization of Hybrid Ni0.5Zn0.5Fe2O4@SiO2/chitosan
In this work we evaluate the use of silane agent 3-aminopropyltrimethoxysilane and biopolymer chitosan to functionalize ferrites Ni0.5Zn0.5Fe2O4 using the solvent evaporation method aiming at obtaining hybrid material Ni0.5Zn0.5Fe2O4@SiO2/chitosan for use as a biosensor. The nanoparticles before and after the functionalization showed the major phase Ni0.5Zn0
Mat. Res.. Publicado em: 24/08/2017
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11. 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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12. 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