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(1999), 4421-4423. BUTVIN, P.—BUTVINOVÁ, B.—SITEK, J.—DEGMOVÁ, J.—VLASÁK, G.—ŠVEC, P.—JANIČKOVIČ, D.: Magnetic properties and macroscopic heterogeneity of FeCoNbB Hitperms, Journal of Magnetism and Magnetic Materials 320 (2008), 1133-1140. BUTVINOVÁ, B.—BUTVIN, P.—VLASÁK, G.—ŠVEC, P.—JANIČKOVIČ, D.: Secondary magnetic anisotropy in Hitperms, Reviews on Advanced Materials Science 18 (2008), 509-512.

R eferences [1] L. Piotrowski, B. Augustyniak, M. Chmielewski and I. Tomas, “The influence of plastic deformation on the magnetoelastic properties of the CSN12021 grade steel”, J.Magn. Magn. Mater. , vol. 321 pp. 2331-2335, (2009). [2] O. Stupakov, T. Uchimoto and T. Takagi, “Magnetic anisotropy of plastically deformed low-carbon steel”, J. Phys. D: Appl. Phys. , vol. 43 195003 (7p), (2010). [3] C. Gatelier-Rothea, J. Chicois, R. Fougeres and P. Fleischmann, “Characterization of pure iron and (130 ppm) carbon-iron binary alloy by Barkhausen noise measurements

efficient implementation of the strongly contracted and of the partially contracted variants. J. Chem. Phys., 117, 2002, 9138. ANGELI, C., BORINI, S., CESTARI, M., CIMIRAGLIA, R.: A quasidegenerate formulation of the second n-electron valence state perturbation theory approach. J. Chem. Phys., 121, 2004, 4043. ATANASOV, M., GANYUSHIN, D., PANTAZIS, D.A., SIVALINGAM K., NEESE, F.: Detailed ab initio first-principles study of the magnetic anisotropy in a family of trigonal pyramidal iron(II) pyrrolide complexes. Inorg. Chem., 50, 2011, 7460-7477. BOČA, R.: Zero

practical materials due to high magnetostriction and low magnetic anisotropy, they are not cost-effective enough for commercial applications because Terfenol-D consists mostly of heavy rare earths, Tb and Dy, which are both expensive and scarce in the earth crust. Therefore, a novel magnetostrictive compound based on the lower cost light rare earth is highly desired. Recently, the development of Laves alloys containing Nd element has been a hot research topic, owing to NdFe 2 possessing a large theoretical magnetostriction (λ 111 ~ 2000 ppm at 0 K) and a low magnetic

-molecule magnet: A macrocyclic approach to designing magnetic anisotropy. Angew. Chem. Int. Ed. , 50 , 4016–4019. 65. Chilton, N. F. (2013). PHI User Manual v1.7. 66. Clemente-Juan, J. M., Coronado, E., & Gaita-Arino, A. (2012). Magnetic polyoxometalates: from molecular magnetism to molecular spintronics and quantum computing. Chem. Soc. Rev ., 41 , 7464–7478.

Abstract

Three nCo,N-TiO2 nanocomposites (where cobalt concentration index n = 1, 5 and 10 wt %) were prepared and investigated by magnetic resonance spectroscopy at room temperature. Ferromagnetic resonance (FMR) lines of magnetic cobalt agglomerated nanoparticle were dominant in all registered spectra. The relaxation processes and magnetic anisotropy of the investigated spin system essentially depended on the concentration of cobalt ions. It is suggested that the samples contained two magnetic types of sublattices forming a strongly correlated spin system. It is suggested that the existence of strongly correlated magnetic system has an essential influence of the photocatalytic properties of the studied nanocomposites.

Abstract

Highly-ordered ternary Fe-Co-Ni alloy nanowire arrays with diameters of about 50 nm have been fabricated by alternating current (AC) electrodeposition into the nanochannels of porous anodic aluminum oxide templates. SEM and TEM results indicate that the alloy nanowires are highly ordered. XRD and HRTEM results show that the ternary FeCoNi alloy nanowires are polycrystalline, with HCP-FCC dual phase structure. Magnetic measurements demonstrate that the ternary alloy nanowire arrays have an obvious magnetic anisotropy with an easy magnetization direction being parallel to the nanowire arrays. Along the easy magnetization direction, the coercivity (Hc) and squareness ratio (S) increase as the annealing temperature increases, and reach a maximum level (Hc = 1337 Oe, S = 0.96) at 300 °C.

Abstract

Two composites consisting of γ-Fe2O3 (maghemite) nanoparticles covered by two different oxygen-based free radicals derived from a 4-(methylamino)phenol sulphate and 8-hydroxy-1,3,6-trisulfonic trisodium salt acid were prepared and investigated by the magnetic resonance method in the 4–300 K range. Both composites displayed broad and very intense ferromagnetic resonance (FMR) lines originating from γ-Fe2O3 agglomerated nanoparticles. The FMR spectrum was fitted satisfactorily at each temperature by two Landau-Lifshitz functions reflecting the existence of magnetic anisotropy in the investigated system. The temperature dependence of the obtained FMR parameters (resonance field, linewidth, integrated intensity) was studied and the results were interpreted in terms of magnetic interactions between free radicals and nanoparticle agglomerates. A comparison with previously studied similar systems containing maghemite nanoparticles was made and conclusions about the role of free radicals were drawn.

Abstract

The effect of electrodeposition potential on the magnetic properties of the FeCoNi films has been reported in this paper. The FeCoNi electrodeposition was carried out from sulfate solution using potentiostatic technique. The obtained FeCoNi films were characterized by X-ray diffractometer (XRD), atomic absorption spectrometer (AAS) and vibrating sample magnetometer (VSM). It has been shown that the electrodeposition potential applied during the synthesis process determines the magnetic characteristics of FeCoNi films. The more negative potential is applied, the higher Ni content is in the FeCoNi alloy. At the same time, Co and Fe showed almost similar trend in which the content decreased with an increase in applied potential. The mean crystallite size of FeCoNi films was ranging from 11 nm to 15 nm. VSM evaluation indicated that the FeCoNi film is a ferromagnetic alloy with magnetic anisotropy. The high saturation magnetization of FeCoNi film was ranging from 86 A·m2/kg to 105 A·m2/kg. The film is a soft magnetic material which was revealed by a very low coercivity value in the range of 1.3 kA/m to 3.7 kA/m. Both the saturation magnetization and coercivity values decreased at a more negative electrodeposition potential.

Abstract

Nanocrystalline iron was obtained by fusing magnetite and promoters. The oxidized form was reduced with hydrogen and passivated (sample P0). The average nanocrystallite size in sample P0 was d(P0) =16 nm and the width of size distribution was σ(P0) = 18 nm. Samples of nanocrystalline iron with narrower diameter ranges and larger and smaller average crystallite sizes were also synthesized. They were: sample P1 (d(P1) = 28 nm, σ(P1) = 5 nm), sample P2 (d(P2) = 22 nm, σ(P1) = 5 nm), sample P3 (d(P3) = 12 nm, σ(P1) = 9 nm). These four samples were studied at room temperature by dc magnetization measurements and ferromagnetic resonance at microwave frequency. Correlations between samples sizes distributions (average size and width of the sizes) and magnetic parameters (effective magnetization, anisotropy field, anisotropy constant, FMR linewidth) were investigated. It was found that the anisotropy field and effective magnetization determined from FMR spectra scale linearly with nanoparticle sizes, while the effective magnetic anisotropy constant determined from the hysteresis loops decreases with nanoparticle size increase.