[en] Scanning electron microscope (SEM) images of polished surfaces, electron probe microanalysis, and X-ray powder diffractometry indicated the presence of a continuous Zr₂Fe phase with secondary phases of ZrFe₂, Zr₅FeSn, α-Zr, and Zr₆Fe₃O. A statistically-designed experiment to determine the effects of temperature, time, and vacuum quality On activation of St 198 revealed that when activated at low temperature (350 degrees C) deuterium absorption rate was slower when the vacuum quality was pwr (2.5 Pa vs. 3x10^-4 Pa). However, at higher activation temperature (500 degrees C), deuterium absorption rate was fast and was independent of vacuum quality. Deuterium pressure-composition-temperature (P-C-T) data are reported for St 198 in the temperature range 200--500 degrees C. The P-C-T data over the full range of deuterium loading and at temperatures of 350 degrees C and below is described by: K_0e-(ΔH_α/RT)=PD₂q²/(q*-q)² where ΔHα and K₀ have values of 101.8 kJ·mole^-1 and 3.24x10^-8Pa^-1, and q* is 15.998 kPa·L^-1·g^-1. At higher temperatures, one or more secondary reactions in the solid phase occur that slowly consume D₂ from the gas phase. XRD suggests these reactions to be: 2 Zr₂FeD_x → x ZrD₂ + x/3 ZrFe₂ + (2 - 2/3x) Zr₂Fe and Zr₂FeD_x + (2 -1/2x) D₂ → ZrD₂ + Fe, where 0 < x < 3. Reaction between gas phase deuterium and Zr2FC formed in the first reaction accounts for the observed consumption of deuterium from the gas phase by this reaction

[en] Concentration dependences of Curie point T_c and compensation point T_k of ferrimagnetic Dy_xCo_1-x films are calculated by mean field method. Rotation moment curves near T_k are constructed. Behaviour of induction hysteresis loops under various directions of the external magnetic field is investigated

[en] Possibility of using controlled anodic oxidation for analysis of film structures on the basis of anodized metals (Nb, Ta, Al, etc.) in the regimes of voltage linear scanning in time on electrolyte cell and constant current density is considered. Method for calculating oxygen concentration profiles of structures oxide-metal, metal-oxide, metal-oxide-metal, metal-metal is proposed. Comparative analysis of experimentally obtained concentration profiles by methods of the anodic oxidation auger-spectroscopy methods in combination with surface ion spraying for model structures Nb-Nb₂O₅-Nb and Nb-Al-Nb-Al-Nb-Si is carried out. Possibility of evaluating degree of roughness for interface boundary of metal-dielectric substrate (within the microbulge range of 2-20 nm) is determined

[en] By following the theory of quantum transport and rough surface scattering developed by Tesanovic et al., the authors present in this paper a microscopic calculation of electronic conductivity in metallic thin wires. The rising of conductivity with the increase of the radius of a wire has a more complicated oscillatory structure than that found in thin films. The scattering on the rough surface in wires can lead both to the violation of Mattheissen's rule and to the localization of electronic states

[en] The first ever band-structure calculations performed for the intermetallic compounds ABi₂ (A = K, Rb, Cs) using the Linear Muffin-Tin Orbital Method are reported. Metallicity in these compounds is found to be primarily due to the A-Bi bonding and the density of states at the Fermi energy is found to be mainly due to the Bi-6p electrons. As the A-atom of these compounds belong to the same group, the calculated band structures and the other parameters such as E_F, N(E_F) etc. exhibit similar characteristics. With the use of the results of the band structure calculations, their superconducting properties are also studied. The theoretically calculated values of T_c are found to be in good agreement with the corresponding experimental values

[en] In this paper epitaxial Fe/Mo/Fe sandwiches grown onto a Mo(100) single crystal are characterized in situ by electron diffraction and the magneto-optic Kerr effect. The intervening Mo layer is wedge shaped to facilitate the study of the magnetic coupling between the two (14-monolayer thick) Fe films as a function of Mo thickness. The exchange coupling between the Fe films across Mo was found to exhibit oscillatory behavior between antiferromagnetic (AF) and ferromagnetic coupling with a periodicity of ∼3 ML of Mo. The shape of the hysteresis loop of the AF-coupled samples was calculated from a simple n/model that reproduces most of the experimental features

[en] The list of physical properties which are important in the design of materials and which are routinely calculated from first principles within the local density approximation to density functional theory is continually growing. In this paper the authors discuss the application of multiple scattering theory to the calculation of the residual resistivity of disordered alloys. Progress has been made on two fronts. First, the coherent potential approximation for the resistivity, which sums to all orders a limited set of multiple scattering diagrams, has given resistivities in agreement with experiment for alloys where the site occupation is roughly random. Second, the linearized KKR was used to evaluate the Kubo formula for several large configurations of atoms and obtain the resistivity with all multiple scattering paths included. This method is not limited to random alloys, but can be applied to short range ordered and amorphous alloys provided the resistivity is high enough to limit the mean free path to a single unit cell

[en] The present work is part of a general study on the thermal and thermomechanical effects on the superplastic alloy Al15%Ca5%Zn using a positron annihilation technique. In a previous work, the authors showed the existence of two contributions to the intensity of the second component of the temporal spectrum in thermally aged samples. This work adds results obtained from monotonically deformed samples at the same aging temperature. (Author)

[en] The variation of the in-the-film-plane anisotropy constant, K_u, with composition and the magnitude of the field, H_s, applied in plane during the sputter deposition of amorphous Sm_xCo_1-x, 0.08≤x≤0.40, thin films has been studied. We demonstrate here that with a large H_s, 5.0 kOe, a well defined and large in-the-film-plane anisotropy can be obtained. An exceptionally high value of K_u=3.3x10⁶ erg/cm³ has been obtained. For the loop measured along the in-plane hard direction, the opening of the loop was undetectable, and the loop along the easy axis was a perfect rectangle. For certain conditions, the anisotropy field measured perpendicular to the film plane when corrected for demagnetization (N_d=4π) was the same as that for the in-plane measurements. It is concluded that surface induced short range ordering was the origin of the anisotropy observed in amorphous films deposited in a magnetic field. The formation mechanism is different from that of the short range ordering induced by field annealing

[en] The new magnetic phases, involving spin-slip and helifan structures, which have recently been identified in Ho, are described. The genesis of these structures and the cone in the competing magnetic interactions, and their possible significance for other rare-earth systems, are discussed. (orig.)