Hysteresis Loops
Mostrando 1-12 de 33 artigos, teses e dissertações.
-
1. Cation Vacancies in NiFe2O4 During Heat Treatments at High Temperatures: Structural, Morphological and Magnetic Characterization
Nickel ferrite (NiFe2O4) was synthesized by mixing stoichiometric amounts of α-Fe2O3 and NiO using mechanical milling and heat treatments at high temperatures. The physical characterization of the samples was carried out using X-ray diffraction, infrared and Raman spectroscopies, Mössbauer spectrometry, magnetization measurements, scanning electron microsc
Mat. Res.. Publicado em: 20/12/2019
-
2. Diameter Dependence of Magnetic Properties of Co-based Metal Fibers
Naked Co68.25Fe4.5Si12.25B15 metal fibers with diameter from 25 µm to 100 µm are produced by melt extraction method. Significant diameter dependence of magnetic properties is studied. Their microstructure and magnetic properties of hysteresis loops and giant magneto impedance (GMI) effect at frequencies from 0.1MHz to13MHz are investigated. The results sho
Mat. Res.. Publicado em: 09/09/2019
-
3. A Study of the Thermal Runaway Phase Generated During Cyclic Loading of Viscoelastic Materials Accounting for the Prestress
Abstract The good damping performance and inherent stability of viscoelastic materials in relatively broad frequency bands, besides cost effectiveness, offers many possibilities for practical engineering applications. However, for viscoelastic dampers subjected to dynamic loadings superimposed on static preloads, especially when good isolation characteristic
Lat. Am. j. solids struct.. Publicado em: 2016-12
-
4. Preparation and Properties of Epoxy Resin-Coated Micro-Sized Ferrosilicon Powder
Ferrosilicon powder surface coated with a dense epoxy resin membrane was prepared via coating precipitation methods using silane coupling agents as the modifier and epoxy resin as the coating agent. FTIR, FESEM, MPMS-XL, and TG-DSC were used to analyze the morphology, surface composition, magnetic property and thermostability of ferrosilicon powder before an
Mat. Res.. Publicado em: 07/07/2016
-
5. The Effects of High Magnetic Field Annealing on the Structural Relaxation of Fe71(Nb0.8Zr0.2)6B23 Bulk Metallic Glass
Fe-based magnetic metallic amorphous and nanocomposites have excellent soft magnetic properties including greater magnetization and magnetic permeability compared with crystalline alloys, especially at high operation frequency and temperature. The high magnetic field (HMF) up to 12T is introduced to the heat annealing of Fe71(Nb0.8Zr0.2)6B23 bulk metallic gl
Mat. Res.. Publicado em: 04/12/2015
-
6. Numerical and theoretical studies of bolted joints under harmonic shear displacement
A three-dimensional finite element model used to simulate the bolted joint is created using ABAQUS package. The stress concentration factors at the roots of the thread are first studied with a preload of 38.4 kN. Under harmonic transverse shear displacement, not only the stress variations at ten specified points of the first thread but also contact condition
Lat. Am. j. solids struct.. Publicado em: 2015-01
-
7. Synthesis and characterization of Fe3O4 nanoparticles with perspectives in biomedical applications
Nowadays the use of magnetic nanoparticles (MNP) in medical applications has exceeded expectations. In molecular imaging, MNP based on iron oxide coated with appropriated materials have several applications in vitro and in vivo studies. For applications in nanobiotechnology these MNP must present some characteristics such as size smaller than 100 nanometers,
Mat. Res.. Publicado em: 29/04/2014
-
8. Facile synthesis of inverse spinel NiFe2O4 nanocrystals and their superparamagnetic properties
Spinel NiFe2O4 nanocrystals have been obtained by means of a novel composite-hydroxide-salt-mediated approach, which is based on a reaction between metallic salt and metallic oxide in the solution of composite-hydroxide-salt eutectic at ~225 ºC and normal atmosphere without any organic dispersant or capping agent. The obtained products are characterized by
Mat. Res.. Publicado em: 22/11/2012
-
9. Computation of multiple limit cycles in nonlinear control systems - a describing function approach
Abstract Limit cycles play an important role in nonlinear systems, provided that many control loops with common nonlinearities like relay, hysteresis, and saturation can present them. Thus, a proper description of this nonlinear phenomenon is highly desirable. A strategy for the linearized analysis is the describing function method, which is a frequency doma
J. Aerosp. Technol. Manag.. Publicado em: 2011-04
-
10. SÍNTESE E CARACTERIZAÇÃO DE NiFe2O4 E EFEITOS DA DOPAGEM NA MAGNETIZAÇÃO DE SATURAÇÃO. / SYNTHESIS AND CHARACTERIZATION OF NiFe2O4 AND EFFECTS OF DOPING IN MAGNETIC SATURATION.
The ferrites are a wide class of ferrimagnetic materials with great technological importance and are studied extensively for many decades. Their remarkable magnetic characteristics make it an element often used in induction transformers by his high magnetic permeability, high values of saturation magnetization and low coercivity, resulting in smaller losses
Publicado em: 2011
-
11. Síntese e caracterização de copolímeros à base de poli(metacrilato de metila) e divinilbenzeno com propriedades magnéticas / Synthesis and characterization of copolymers based on methyl methacrylate, divinylbenzene with magnetic properties
In this dissertation, copolymers based on methyl methacrylate (MMA) and divinylbenzene (DVB) with magnetic properties were synthesized by suspension polymerization. It was employed iron as magnetic material. The influence of reaction variables for the microspheress formation as order of addition of the organic and aqueous phases, dispersion of iron before an
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 14/07/2010
-
12. Propriedades de exchange bias e congelamento de spins de superfície em nanopartículas magnéticas
We present here magnetization measurements performed at low temperatures on magnetic nanocolloids based on 3.3 nm sized particles of manganese ferrite. This nanocolloid was obtained by a chemical core/shell strategy developed for the synthesis of ferro uids. Temperature dependence of the magnetization measurements allowed us to separate two contributions. On
Publicado em: 2009