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The effect of annealing current density on the structure of the resulting nanocrystalline phase in the amorphous [Fe.sub.73.9][Nb.sub.3.1][Cu.sub.0.9][Si.sub.13.2][B.sub.8.9] alloy is examined. The ex situ Mossbauer spectroscopy measurements on current annealed samples have indicated a variation, with increasing current density, in the composition of the nanocrystalline grains and/or the amorphous grain boundary phase.

The synthesis, structure and thermoelectric properties of [Ca.sub.m][Ce.sub.n][Fe.sub.x][Co.sub.[4-x]][Sb.sub.12] compounds, where Ca and Ce are used as filling atoms simultaneously, are investigated. The results have shown that the greatest dimensionless thermoelectric figures of merit (ZT) value of 1.2 is obtained at 750 K for p-type [Ca.sub.0.18][Ce.sub.0.12][Fe.sub.1.45][Co.sub.2.55][Sb.sub.12] compound in all the samples.

The microstructure and high temperature magnetic properties of Fe-Co-2V and Fe-Co-2V-0.3Nb alloys are investigated. In the Fe-Co alloys the soft magnetic property are strongly influenced by the gamma2 phase precipitated at high temperature.

Thermal-induced microstructural changes of nickel-iron cyanide prepared by coprecipitation were studied. Above 550 degree Celsius, the cyanide compound decomposed into a mixture of fcc Fe-Ni and amorphous carbon.

Magnetic properties of thermally aged Fe-1wt.%Cu alloys were investigated. With increasing aging time, coercive force gradually increased and Barkhausen signal peak voltage decreased. Both behaviors suggested that Bloch wall movement was hindered by Cu precipitates and the pinning was strengthened with increasing precipitate size. On the other hand, at the initial precipitation stage where the precipitate size is much smaller than the Bloch wall width, the inclination of the hysteresis curve greatly changed, but recovered with further thermal aging. The peculiar inclination behavior would be associated with the nucleation of coherent bcc-Cu precipitates. Index Terms--Anisotropy, Barkhausen noise (BHN), coercive force, hysteresis curve, nondestructive evaluation (NDE), precipitation, thermal aging.

The hysteretic losses of a series of eight nanocrystalline soft magnetic alloys with compositions (Fe,Co,Ni)-Zr-B-Cu are investigated. The lower coercivity values observed in alloys containing Cu are attributed to grain refinement and the reduction in hysteresis losses is observed for the nanocrystalline alloy with composition [([Fe.sub.0.75][Co.sub.0.125][Ni.sub.0.125]).sub.85.5][Zr.sub.8.5][B.sub.5][Cu.sub.1].

Chemical synthesis is used for preparing the FePt nanoparticles with controlled composition. The difference in Curie temperature between the heating and cooling thermomagnetic curves of the Fe-Pt alloys is attributed to the difference of [alpha] [left right double arrow] [gamma] phase transition temperature during heating and cooling.

Hard magnetic [L1.sub.0]-[Fe.sub.51][Pt.sub.49] thin films with out-of-plane texture and film thicknesses are prepared on MgO(001) single crystalline substrates by co-sputtering and are magnetically examined by SQUID magnetometry at different temperature range. The microstructural parameters are ascertained by studying the temperature dependence of the coercivty within the framework of micromagnetism, which has helped in understanding the magnetic reversal process.

The effect of the Mn content on the magnetocaloric response of ribbon-shaped amorphous samples of [Fe.sub.80-x][Mn.sub.x][B.sub.20] is analyzed by obtaining the temperature and field dependence of the magnetic entropy change from magnetization curves. A linear relationship between the maximum entropy change and the average magnetic moment per transition metal atom is described.

Metallic glass formation is seen in rapidly quenched quaternary Dy[Mn.sub.6-x][Ge.sub.6][Fe.sub.x] (0

The non-resonant and soft resonant magnetic x-ray scattering technique is employed to explain the impact of annealing on the junction profile of the various different CoFeB/MgO tunnel junctions. The structural quality of the junctions is shown to remain unaffected by the annealing procedure.

Magnetic properties of [Zn.sub.x][Fe.sub.1-x]O nanopowder and [Zn.sub.1-x-y][Fe.sub.x][Mg.sub.y]O ceramic samples are examined at different temperatures, showing in the latter compound ferromagnetic (FM) interactions up to T = 330 K. Strong growth of the magnetization and room temperature ferromagnetism are seen in [Zn.sub.0.70][Fe.sub.0.04][Mg.sub.0.26]O where the magnetic susceptibility has followed the scaling law [[X.sup.-1](T)-[X.sup.-1](Tc)]

Iron selenide with the nominal composition [Fe.sub.1.03]Se is prepared by a self-flux solution method that has indicated a zero resistance temperature up to 10.9 K and a [T.sub.c.sup.onset] up to 13.3 K. The decrease in superconducting transition temperature by heat treatment has shown that internal crystallographic strain that has played the same effect as external pressure is the origin of its high [T.sub.c].

An anomalous angular dependence of the coercive field of physically nonpercolated granular CoFeB-Si[O.sub.2] films with oriented anisotropy of the granules, where the presence of the superferromagnetic phase is established, is seen at temperatures above the blocking temperature. The studies have shown that the anomaly is determined by a singularity of the angular dependence of the critical field causing the absolute loss of the superferromagnetic phase stability in the ensemble of weakly interacting ferromagnetic nanoparticles.

The mechanisms involved in the synthesis of the various high-Curie-temperature [Fe.sub.0.02][Ge.sub.0.98] quantum dots are explained. The application of the compound for the development of a new class of spintronics devices is also discussed.

The fabrication and the various magnetic and martensitic properties of the different Ni-Fe-Ga melt-spun ribbons are discussed. The properties of these ribbons are shown to be highly dependent on the quenching rate.

The low-temperature anomaly is revealed in the temperature and angular dependencies of the coercivity in granular [(CoFeB)-[(Si[O.sub.2]).sub.1-x] films with oriented in-plane anisotropy. The results are described in terms of a random field model, which has described the onset of spin glass-like correlations in the ensemble of oriented weakly interacting Stoner-Wohlfarth particles.

The suitability of the demixing process for self-organized formation of exchange coupled thin film magnets is examined. The studies have shown the different thermodynamic and kinetic conditions required for demixing and ordering, where the interfaces energy during demixing must be considered for nanostructures.

The thermoelectric properties of LaFeAs[O.sub.1-y] at low temperature are studied. The results have shown that iron pnictides have potential as a good low temperature thermoelectric material.

A simple reaction of [I.sub.2] vapor with both powder and single crystal samples has helped in removing the interstitial iron from the FeTe framework topotactically. The studies have shown that the deintercalation process has consequences for both magnetic and crystallographic phase transitions in the compound at low temperatures.

The light and heat induced transformation between diamagnetic [Fe.sub.LS.II]([micro]-CN)[Co.sub.LS.sup.III] (LS = low spin) units and paramagnetic [Fe.sub.LS.sup.III]([micro]-CN)[Co.sub.HS.sup.II] (HS = high spin) units is exploited to show the photoswitched transformation from a paramagnetic state to an antiferromagnetic ordered single-chain magnet (SCM) state and the thermally induced reverse transformation. An effective way is provided to control the spin topology of the SCM through light or a thermally induced metal-to-metal charge transfer.

A combination of differential scanning calorimetry and thermomagnetic measurements is employed to explain the magnetic transformation taking place in the Ni-Fe-Ga-Co alloys. The field dependent thermomagnetic hysteresis of the alloys is shown to be dependent on the field.

High temperature powder x-ray diffraction study is used for analyzing 0.8BiFe[O.sub.3]-0.2Pb([Fe.sub.1/2][Nb.sub.1/2])[O.sub.3], which is isostructural with the multiferroic BiFe[O.sub.3] (BF). The studies have shown that the room temperature ferroelectric phase of 0.8BF-0.2PFN in the R3 space group has transformed to the paraelectric/paraelastic cubic phase directly without any intermediate '[beta]' phase observed for pure BF.

Several studies are conducted to explain the different effects of partial substitution of Ge by Ga on the elastic, as well as magnetoelastic properties of the different Fe-Ga alloys. The saturation magnetostriction and the magnetic-field saturated shear elasticity exhibited by these alloys at different temperature ranges are also determined.

Several studies are conducted to explain the impact of temperature on the magnetostriction of the stress annealed Galfenol material, which is shown to be highly magnetostrictive active. The results demonstrate that stress does not have any major impact on the saturation magnetorestriction of this material.

The article explains the microstructure, as well as the mganetocaloric effects of the various La[Fe.sub.10.8][Co.sub.0.7][Si.sub.1.5][C.sub.0.2] compounds observed at different annealing times. The grains of the compounds are shown to considerably increase with an increase in the annealing time.

The thermal stability, magnetocaloric effect and the refrigeration capacity of the various [Gd.sub.65][Fe.sub.20][Al.sub.15- x][B.sub.x] (x = 0- 7) glassy ribbons are determined. The glassy structure of the ribbons is shown to lead to higher values of the refrigeration capacity.

Several thermomagnetic analyses are conducted to explain the various magnetic properties, as well as the microstructure of the different directly quenched NdFeTiZrCrBC bulk magnets. A slight substitution of the C and Cr contents is shown to lead to significant enhancement of the properties.

Several analyses are conducted to explain the microstructural changes of the Nd-rich phases taking place in the Nd-Fe-B sintered magnet during the postsintering annealing process. The reduction in the lattice mismatch is shown to be the main factor that leads to an enhancement of the magnetic properties of the compounds.