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The magnetization, thermal conductivity and thermopower of polycrystalline samples of [Nd.sub.1-x][Eu.sub.x]Ni[O.sub.3] compounds are measured as a function of temperature and external magnetic field. The results have shown a coexistence of ordered and disordered phases below the temperature [T.sub.N] and that an applied magnetic field is suitable for increasing the thermoelectric properties close to [T.sub.S].

Several analyses are conducted to explain the synthesis and the structural, magnetic and thermal properties of the [Nd.sub.1-x][La,sup.x]Cr[O.sub.3] (0

Polycrystalline samples of [([La.sub.1-x][A.sub.x]).sub.0.67][Ba.sub.0.33][mn.sub.1.05][O.sub.3-[delta]] (with A being a mixture of lanthanides containing 66%La, 22%Nd, 8%Pr and 4%Ce) are prepared by the glycine-nitrate method. The results have shown that replacing lanthanum with a mixture of lanthanides is a good way to tune the working temperature of magnetocaloric manganites while maintaining a constant magnetocaloric effect.

The various effects of hydostatic pressure on the ferromagnetic phase transition and magnetocaloric properties of the [([Sm.sub.0.8][Nd.sub.0.2]).sub.0.52][Sr.sub.0.48]Mn[O.sub.3] single crystals are determined. The magnetization of the crystals is shown to increase considerably with the application of pressure.

Several studies are conducted to explain the structure, magnetic properties and the magnetocaloric effect observed in the various [Nd.sub.5][Si.sub.3] compounds. The compounds are shown to be extremely beneficial for a large number of magnetic refrigeration applications.

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.

The article presents a new approach, which employs the melt spinning and jet milling techniques for the preparation of high performance nanostructured Nd-Fe-B fine powders. The different effects of the jet milling conditions on the particle size and magnetic properties of these powders are also studied.

The impact of temperature on the spontaneous remagnetization observed in the various [Nd.sub.60][Fe.sub.30][Al.sub.10] and [Nd.sub.60][Fe.sub.20][Co.sub.10][Al.sub.10] bulk amorphous ferromagnets is discussed. The spontaneous remagnetization measure is shown to increase linearly with the temperature.

Several magnetic measurements and electron microprobe analyses are conducted to explain the microstructures, as well as the magnetic properties of the various sintered MR[E.sub.2][Fe.sub.14]B magnets (MRE = Y+Dy+Nd). Composition segregation of grains is shown to lead to the higher temperature coefficients in these magnets.

A study was conducted to examine NdMnSiH by magnetization and specific heat measurements. Findings highlight the magnetic properties, magnetic structures, and values of Nd and Mn ordered magnetic moments.

The temperature dependent thermoelectric power (TEP) studies has being carried out on [Nd.sub.0.67][Sr.sub.0.33]Mn[O.sub.3] nanocrystalline manganites to study the effect of nanosize on thermopower behavior of these manganites. Results result that magnon drag contribution predominantly contributes to the TEP in the ferromagnetic metallic (FMM) region.

The synthesis of [Nd.sub.25][Fe.sub.40][Co.sub.20][Al.sub.10][B.sub.5] by high-energy milling and melt-spinning techniques followed by subsequently annealed temperature range from 400 to 1100 degree Celsius for 20 min, is described. The findings from x-ray diffraction combined with high-resolution transmission microscopy for the annealed samples showed the presence of ferromagnetic [Nd.sub.2][(Fe,Co,Al).sub.14]B crystallites coexisting with antiferromagnetic [Nd.sub.6][(Fe,Co,Al).sub.14] ones, among an amorphous matrix.

Magnetic and thermodynamic measurements for [R.sub.5]Ni[Pb.sub.3] (R=Ce, Nd, Gd) are described. Nonmagnetic [La.sub.5]Ni[Pb.sub.3] is used for isolating the magnetic heat capacity for all three materials and the results have included a relatively large linear-T term in the specific heat and integrated magnetic entropies consistently smaller than expected.

Neutron diffraction patterns are acquired in situ from a melt-spun amorphous [Fe.sub.74][Nd.sub.5][B.sub.18][Cr.sub.3] alloy upon rapid thermal annealing at constant rates. The heterogeneous nucleation of [Nd.sub.2][Fe.sub.14]B on tetragonal-[Fe.sub.3]B precipitates promoted by the 3d transition-metal additives is used for magnetic hardening.

Conventional and anisotropic magnetocaloric effects are studied in cubic rare earth R[Ni.sub.2] (R = Nd, Gd, Tb) ferromagnetic intermetallic compounds. The crystalline electrical-field anisotropy is explored for predicting the anisotropic magnetotropic behavior and the results have shown the possibility of using both conventional and anisotropic magnetic entropy changes to extend the range of temperatures for use in the magnetocaloric effect.

A study was conducted to explore the possibility of orienting [Nd.sub.2][Fe.sub.14]B solid particles in a nonmagnetic liquid phase under a magnetic field applied on a ribbon heated at a temperature above the melting temperature of the eutectic phase. The large temperature effect on the orientation behavior is attributed to the associated increase in the liquid phase volume fraction.

Magnetic, thermal and transport properties of NdNiPb and [Nd.sub.5]Ni[Pb.sub.3] and their crystalline electric field (CEF) splitting effects are examined. [Nd.sub.5]Ni[Pb.sub.3] has displayed a ferrimagnetic transition, whereas NdNiPb has displayed an antiferromagnetic phase transition associated with the alignment of crystal-field-split levels of the magnetic Nd ion and transport properties closer to those of a classic metallic system.

The structural, magnetic and magnetocaloric effect (MCE) of [La.sub.1-x][Nd.sub.x][Fe.sub.11.5][Al.sub.1.5] compounds are examined. The magnetocaloric effect has increased with Nd substitution and the refrigerant capacity is also large in Nd-substituted compounds, which is attributed to the tablelike MCE arising from the multiple transitions.

The ferromagnetism transition of [Nd.sub.1-x][Sr.sub.x]Mn[O.sub.3] compounds is examined by measuring magnetocaloric effect (MCE) and by applying a theoretical model based on Landau theory of phase transitions. The results have shown that the contributions to the free energy from the presence of correlated clusters have affected the MCE by coupling with the order parameter around the Curie temperature.

Electrical resistivity, heat capacity and dc magnetization measurements are performed on the Al[B.sub.2]-type intermetallics NdCuGe and LaCuGe over a wide temperature range. Simple-metallic behavior has provided a good fit to the NdCuGe thermopower and hence the CeCuGe results are attributed to resonant scattering due to partial hybridization of the localized orbitals.

Melt-spinning in the form of ribbons is used to prepare and study the magnetic properties of the [Nd.sub.49][Al.sub.13][Ni.sub.38] amorphous alloy. The findings from the hysteresis and temperature-dependent magnetization measurements provide insight into occurrence of a reentrant spin-glass behavior on cooling.

The magnetocaloric effect (MCE) is seen in three well-defined temperature intervals in polycrystalline [Nd.sub.0.5][Ca.sub.0.5]Mn[O.sub.3] (NCMO) manganite system displaying a first order (CO) transition. In the three given temperature regions, negligible magnetic and thermal hysteresis are observed, which has satisfied the requirements of using NCMO as an effective magnetocaloric material for magnetic refrigeration.

The effects of phase distribution and grain size on the effective anisotropy and coercivity of the exchanged-coupled nanocomposite permanent materials was investigated. The dependence of coercivity on grain sizes is mainly determined by the effective anisotropy of the grains and the experimental enhancement of the coercivity with reducing grain size is attributed not to only the exchange-coupling interactions but also to the phase distribution.