中文
相关论文

相关论文: Validity of the N\'{e}el-Arrhenius model for highl…

200 篇论文

We have studied the magnetic and power absorption properties of three samples of CoFe2O4 nanoparticles with sizes from 5 to 12 nm prepared by thermal decomposition of Fe (acac)3 and Co(acac)2 at high temperatures. The blocking temperatures…

材料科学 · 物理学 2011-03-22 T. E. Torres , A. G. Roca , M. P. Morales , A. Ibarra , C. Marquina , M. R. Ibarra , G. F. Goya

The scope of this article is to report very detailed results of the measurements of magnetic relaxation phenomena in the new Cu$_{0.5}$Fe$_{2.5}$O$_{4}$ nanoparticles and known CuFe$_{2}$O$_{4}$ nanoparticles. The size of synthesized…

介观与纳米尺度物理 · 物理学 2007-05-23 Damir Pajic , Kreso Zadro , Robert E. Vanderberghe , Ivan Nedkov

We report detailed studies on non-equilibrium magnetic behavior of antiferromagnetic Co_3O_4 nanoparticles. Temperature and field dependence of magnetization, wait time dependence of magnetic relaxation (aging), memory effects and…

介观与纳米尺度物理 · 物理学 2015-05-27 Vijay Bisht , K. P. Rajeev

The magnetic behavior of $Fe_{3-x}O_4$ nanoparticles synthesized either by high-temperature decomposition of an organic iron precursor or low-temperature co-precipitation in aqueous conditions, is compared. Transmission electron microscopy,…

Magnetic measurements up to 1000 K have been performed on hydrothermally synthesized $\alpha$-Fe$_{2}$O$_{3}$ nanoparticles (60 nm) using a Quantum Design vibrating sample magnetometer. A high vacuum environment (1$\times$10$^{-5}$ torr)…

介观与纳米尺度物理 · 物理学 2015-05-20 Jun Wang , Wei Wu , Fan Zhao , Guo-meng Zhao

CoFe2O4 nanoparticles were synthesized using gelatin as a polymerizing agent. Structural, morphological and magnetic properties of samples treated at different temperatures were investigated by X-ray diffraction, scanning electron…

材料科学 · 物理学 2015-06-02 A. C. Lima , M. A. Morales , J. H. Araujo , J. M. Soares , D. M. A. Melo , A. S. Carrico

We have studied the magnetic behavior of dextran-coated magnetite (Fe$_3$O$_4$) nanoparticles with median particle size $\left<d\right>=8$ $nm$. Magnetization curves and in-field M\"ossbauer spectroscopy measurements showed that the…

材料科学 · 物理学 2007-05-23 E. Lima , A. L. Brandl , A. D. Arelaro , G. F. Goya

Nanoparticles (size 20, 40 and 60 nm) of Pr_0.5Sr_0.5MnO_3 are prepared by sol-gel technique and their magnetic properties are studied using ferromagnetic resonance and magnetization measurements. A comparison with the properties of the…

强关联电子 · 物理学 2007-06-13 S. S. Rao , S. V. Bhat

Recent work [1] demonstrated high coercivity and magnetic moment in cobalt carbide nanoparticle assemblies and explained the high coercivity from first principles in terms of the high magnetocrystalline anisotropy of the cobalt carbide…

介观与纳米尺度物理 · 物理学 2018-09-26 Pallabi Sutradhar , Shiv N. Khanna , Jayasimha Atulasimha

Co2FeAl (CFA) nanoparticles (NPs) of different sizes were synthesized by chemical route. The effect of the size of NPs upon the structure and magnetization compared to its bulk counterpart was investigated. The structure and composition…

强关联电子 · 物理学 2019-10-01 Aquil Ahmad , Srimanta Mitra , S. K. Srivastava , A. K. Das

Magnetic measurements have been performed on 40-nm sphere-like Fe3O4 nanoparticles using a Quantum Design vibrating sample magnetometer. Coating Fe3O4 nanoparticles with SiO2 effectively eliminates magnetic interparticle interactions so…

介观与纳米尺度物理 · 物理学 2015-05-20 Jun Wang , Pieder Beeli , L. H. Meng , Guo-meng Zhao

A detailed study of the electronic transport and magnetic properties of Fe$_{1-x}$Cu$_x$Cr$_2$S$_4$ ($x \leq 0.5$) on single crystals is presented. The resistivity is investigated for $2 \leq T \leq 300$ K in magnetic fields up to 14 Tesla…

Magnetic properties with 3 different sizes of Ni nanochains, synthesized by a technique of wet chemical solution, have been investigated experimentally. The sample sizes are 50 nm, 75 nm, and 150 nm with a typical length of a few microns.…

介观与纳米尺度物理 · 物理学 2007-05-23 Wangzhi Zheng , Lin He , Chinping Chen , Lin He , Wei Zhou , Chenmin Liu , Lin Guo , Huibin Xu

We report detailed studies on magnetic properties of Co3O4 nanoparticles of average size 12.5 nm. Temperature and field dependence of magnetization, wait time dependence of magnetic relaxation (aging), memory effects and temperature…

介观与纳米尺度物理 · 物理学 2010-09-03 Vijay Bisht , K. P. Rajeev

We present in this paper the structural and magnetic properties of high aspect ratio Co nanoparticles (~10) at high temperatures (up to 623 K) using in situ X ray diffraction (XRD) and SQUID characterizations. We show that the anisotropic…

The dynamic magnetic properties of Ni nanoparticles diluted in an amorphous SiO2 matrix prepared from a modified sol-gel method have been studied by the frequency f dependence of the ac magnetic susceptibility \c{hi}(T). For samples with…

材料科学 · 物理学 2011-03-22 G. F. Goya , F. C. Fonseca , R. F. Jardim , R. Muccillo , N. L. V. Carreño , E. Longo , E. R. Leite

Structural and magnetic properties of Fe@Pt core-shell nanostructure prepared by a sequential reduction process are reported. Transmission electron microscopy (TEM) shows nearly spherical particles fitting a lognormal size distribution with…

介观与纳米尺度物理 · 物理学 2015-10-29 Kelly L. Pisane , Sobhit K. Singh , Mohindar S. Seehra

We present a microscopic model for nanoparticles, of the maghemite ($\gamma $% -Fe$_{2}$O$_{3}$) type, and perform classical Monte Carlo simulations of their magnetic properties. On account of M\"{o}ssbauer spectroscopy and high-field…

材料科学 · 物理学 2009-10-31 H. Kachkachi , A. Ezzir , M. Nogues , E. Tronc

Thermal activation tends to destroy the magnetic stability of small magnetic nanoparticles, with crucial implications in ultra-high density recording among other applications. Here we demonstrate that low blocking temperature ferromagnetic…

介观与纳米尺度物理 · 物理学 2015-07-15 Jose A. De Toro , Daniel P. Marques , Pablo Muniz , Vassil Skumryev , Jordi Sort , Dominique Givord , Josep Nogues

Magnetization and Mossbauer studies have been performed on the polymer coated magnetite nanoparticles with particle size from 5.1 to 14.7 nm. The maximum in the temperature dependence of magnetization (TM) is found to be inconsistent with…

材料科学 · 物理学 2009-11-11 M. Thakur , K. De , S. Giri , S. Si , A. Kotal , T. K. Mandal
‹ 上一页 1 2 3 10 下一页 ›