The superconductive transition temperature of binary and ternary solid solutions in thallium

The transition temperatures of various binary alloys and of ternary alloys in the system Tl Hg _x Sn _y were investigated. By analysing the results different anisotropy parameters were obtained. This was explained by a nonlinear valence dependence of the transition temperature, which can be caused by changes in the topology of the Fermi surface.     

Cluster aspects of binary and ternary fission

On the basis of the statistical approach and calculation of the potential energy of the scission configurations, binary and ternary fissions are described. The text was submitted by the authors in English     

Effective charges in binary and ternary oxide compounds

Effective charges in non-cubic binary oxide crystals are evaluated on the basis of their transverse and longitudinal optical phonon frequencies. The temperature dependence of the effective charge is reported in quartz, rutile and corundum. Three procedures which allow the determination of effective charges in ternary compounds are presented and applied to halogenate, silicate, aluminate and ABO_n-type crystals, where A is an alkali or alkaline earth and B is a transition-metal element. Results are compared with Phillips's ionicities.     

Photophoresis of large volatile drops of binary concentrated solutions in a ternary gaseous mixture: A theory

The motion of large drops of binary concentrated solutions in a ternary gaseous mixture exposed to intense electromagnetic radiation is treated analytically. It is assumed that both components of the solution experience phase transition to the gas phase (carrier gas). The rate of photophoresis for liquid metal (Al + Ag and Sb + Bi) drops of radii 1, 5, and 10 μm is estimated.     

Electrical resistivity of liquid binary and ternary alloys

New method of calculation of the electrical resistivity of liquid and amorphous alloys is presented. The method is based on the Morgan–Howson–S̆aub (MHS̆) model but the pseudopotentials are replaced by the scattering matrix operators. The Fermi energy is properly determined by the accurate values of the phase shifts. The model depends on a very small number of universal parameters and gives stable results. The calculated values of the resistivity agree well with available experimental data for a substantial number of binary alloys. Moreover, the results for some ternary alloys were also obtained.     

Motion of coarse drops of binary concentrated solutions in a nonuniformly heated ternary gaseous mixture: A theory

For coarse drops of binary concentrated solutions with the double phase transition that move in a ternary gaseous mixture via thermophoresis, a theory including thermal diffusion effects is elaborated. The drops consist of water with ethanol dissolved in it. Numerical estimates are made and plots are constructed for the rate of thermophoresis of drops with radii 5, 10, and 15 μm at different ethanol concentrations with and without allowance for volume thermal diffusion.     

Quantum and thermodynamical aspects of binary and ternary fission

A short review is given of the recent developments in the quantum theory of low-energy fission. It is emphasized that angular anisotropy and various angular correlations of fission products are possible only if the fissioning nucleus remains nonthermalized during all the stages of fission from the saddle point to scission. The text was submitted by the authors in English.     

The calculations of cell dimensions of stoichiometric phases and binary and ternary solid solutions with the A15 structure

Equations that successfully reproduce the unit cell dimensions of stoichiometric (i) transition metal-transition metal (T-T) and (ii) transition metal-non-transition metal (T-B) phases with the β-Wolfram or A15 structure in terms of the diameters of the component atoms for CN 12 [J. Less-Common Metals, 81, 161 (1981)], are hear applied to binary and ternary solid solutions with the A15 structure, to discover how well and under what conditions they reproduce the observed lattice parameter variation. That in the main, they perform satisfactorily gives further credence to the model on which they are based, which shows how the various interatomic contacts within the interpenetrating icosahedra and CN 14 polyhedra of the structure, combine together in controlling the cell dimensions of the phases. The model also indicates that it is the contacts between the transition metal atoms that are paramount in controlling a. This fact leads to a specific prediction for the lattice parameter variation in transition-metal-rich solid solutions of T-B phases, which is essentially substantiated for phases of niobium.     

Molecular dynamics of binary metal nitrides and ternary oxynitrides

Ternary systems incorporating metals with oxygen and nitrogen are examined using Tersoff potentials. The apparent success of treating some binary nitride systems using the Tersoff potential is used as a way forward to obtain a new parameter set incorporates atomic features into a series of Tersoff potential for binary nitrides and ternary oxynitrides.     

Bimodal fission in binary and ternary spontaneous fission of 252Cf

The hot bimodal fission of ²⁵²Cf is reexamined with new high-statistics data. We constructed a γ-γ-γ coincidence cube for binary fission and LCP-gated γ-γ matrix for ternary fission. By identifying the secondary fission fragments from their γ-ray transitions, we measured the yields for various fission splits. The normal neutron yield distribution is found to be Gaussian for Xe-Ru. However, the binary fission split of Ba-Mo is found to exhibit a bimodal neutron distribution with the “hot mode” corresponding to ≈3.1% of the total yield. In α ternary fission, the first measurements of yields for specific fission splits are presented. The Te-α-Ru and Xe-α-Mo neutron yields fit well with a single mode, but the Ba-α-Zr split shows evidence for an enhanced hot mode with an intensity of ≈13.8% of the normal mode. The text was submitted by the authors in English.     

Structural and electronic properties of binary and ternary platinum oxides

The structural and crystal chemistry of all known binary and ternary platinum oxides are reviewed with emphasis on the types of polyhedral linkage seen and their relationship to electronic properties. Platinum oxides generally fall into two groups: those containing divalent or partially oxidized platinum in planar coordination and those containing fully oxidized tetravalent platinum in octahedral coordination. Highly conducting platinum oxides contain columnar stacks of partially oxidized planar Pt0₄ groups with direct electronic interactions and tend towards chemical non-stoichiometry. The temperature dependence of electrical conductivity in these compounds is related to the dimensionality of the Pt-Pt interaction. Fully oxidized platinum oxides are either semiconductors or insulators, depending on the type of linkage of the octahedral coordination polyhedra and the Pt-Pt distances. The electronic configuration of octahedrally coordinated Pt⁴⁺ (low spin d⁶) precludes the possibility of metallic conductivity in these materials. In general, platinum metal is found to be fairly reactive in air at elevated temperatures, particularly in the presence of alkali and alkaline earth metals. Therefore, caution should be taken before assuming platinum containers or thermocouples are inert with respect to reactants during high temperature synthesis reactions in air or oxidizing conditions.     

Thermodynamics of molybdenum-niobium-hydrogen ternary solid solutions

The enthalpy of solution of hydrogen has been measured in a series of Mo-Nb solid solutions in the composition range 0–77 at.% Nb. In the solid solutions of Mo and Nb there is good evidence that the enthalpy of solution of H will not be influenced by strain energy factors or by a change in the electronic work function of the metal surface with composition. No correlation between the measured enthalpies and the density of electron states at the Fermi surface was found. The binary Mo-Nb system was chosen because the density of states varies drastically across the system, exhibiting an extremum.     

Enhancement of phononic band gaps in ternary/binary structure

Based on the transfer matrix method (TMM) and Bloch theory, the interaction of elastic waves (normal incidence) with 1D phononic crystal had been studied. The transfer matrix method was obtained for both longitudinal and transverse waves by applying the continuity conditions between the consecutive unit cells. Dispersion relations are calculated and plotted for both binary and ternary structures. Also we have investigated the corresponding effects on the band gaps values for the two types of phononic crystals. Furthermore, it can be observed that the complete band gaps are located in the common frequency stop-band regions. Numerical simulations are performed to investigate the effect of different thickness ratios inside each unit cell on the band gap values, as well as unit cells thickness on the central band gap frequency. These phononic band gap materials can be used as a filter for elastic waves at different frequencies values.     

Kinetic fragility of binary and ternary glass forming liquid mixtures

The experimental studies of liquid fragility in miscible binary and ternary glass forming mixtures reveal a general observation of the negative deviation in fragility upon mixing from the linear average of those of the components. Further analyses from ideal, near ideal to non-ideal mixing modes show that the deviation magnitude does not increase monotonically with mixing enthalpy, and a moderate intermolecular interaction would generate a largest reduction in fragility. Four eutectic systems, methyl-o-toluate-methyl-p-toluate, ZnCl₂-AlCl₃, glycerol-water, and fructose-water, are studied to locate the composition where the largest fragility deviation occurs in phase diagrams. It is found that the compositions with the fragility minima do not coincide with the eutectic points. The results partly explain the experimental observation that the best glass forming region is not located at the eutectic composition.     

Thermodynamic and statistical studies of supersaturated ternary solutions

The influence of chromium ions Cr3+ on properties of supersaturated aqueous solution of ammonium sulfate (NH4)2SO4 has been studied employing containerless electrodynamic levitation of single microdroplets of this solution with known concentration of Cr3+ ions. The water activity versus solute concentration was measured in three different sets of experiments corresponding to different initial concentrations of Cr3+ ions. Theoretical treatment of the experimental results obtained is developed employing the theory of supersaturated electrolyte solutions [Phys. Rev. E 52, 1325 (1995)]. This treatment has allowed the following two conclusions. First, spinodal concentration is a decreasing function of Cr3+ concentration. Second, solute clusters formed in the presence of Cr3+ ions demonstrate complex behavior with respect to binding water molecules: (a) at low and moderate supersaturations, they bind more water molecules than clusters formed in the absence of an impurity; and (b) at high supersaturations, they bind less water molecules than clusters formed in the absence of an impurity.