[en] A consideration was made on the viscosity of binary liquid alloys on the basis of the Enskog theory for this transport process in binary dense fluids and of the real shrinking of the hard sphere diameters with the increasing temperature. The Tham-Gubbins formalism for the viscosity coefficients and the Lebowitz' pair correlation functions were used. Numerical calculations of shear viscosities have been performed for several binary liquid alloys as: Sn-Pb, Bi-Pb, Sb-Cd, Sb-Pb, at different temperatures. A good agreement between the values thus obtained of the viscosities and the available experimental data was found. (author)

[en] A model for dislocation loop formation under irradiation in a face-centered cubic (fcc) A-B alloy is presented. Besides reactions, such as defect production by irradiation, mutual recombination of an interstitial and a vacancy, dislocation loop nucleation, and their growth, conversion among the three types of interstitial dumbbells composed of A- and B-atoms is newly introduced in the formulation, considering the configurations and movements of the dumbbells. The present model is confirmed to give similar loop nucleation behavior to that derived by the conventional model in the case of a dilute alloy. Sample calculations are performed for a concentrated alloy, varying the strength of the binding between A- and B-atoms. Conversion among interstitial dumbbells is demonstrated to play an important role in the loop nucleation process. The atom that dominates loop nucleation varies with the binding of A- and B-atoms. As a result, kinetics of loop nucleation also differ. (orig.)

[en] A new concept, the structural fragility of liquids, has been proposed based on different structural changing behaviors with temperature. A fragility parameter, F_s, was introduced to quantify the structural fragility, and the glass-forming ability (GFA) of some binary alloys was discussed subsequently. The results show that the structural fragility is closely related to the GFA of liquids, a smaller F_s corresponds to a higher GFA

[en] Diffusion of dopants in crystalline structures with arrays of delta-doped layers is studied theoretically. Two types of the structures are treated. The first type is deterministic, defined by a periodic location of the delta-layers. The second type is stochastic, with a Poissonian location of the delta-layers. A general qualitative (semi-quantitative) discussion is given laying emphasis on stochasticity as a prerequisite of any realistic theory of the diffusional homogenization of sintered materials

[en] Binary alloys containing up from 0 % to 18 % silicon at intervals of 3 % we have been produced by casting. Each specimen was lathed, and had a dimension of 46mm length, 16mm diameter. Effect of silicon on the vibration damping of Al-Si alloys have been investigated using an impluse method which an iron ball, 1.95gr weight, 4.0mm diameter, was fallen from a height 150mm freely, and gave an impulse to middle of a specimen. The relation of frequencies-intensity(dB) from which its maximum natural frequency can be obtained was measured by both the condenser microphone(B and K no.4165) and the digital frequency analyser(B and K no. 2131C). A decrease in quantity of the relative logarithmic decrement δ _Re concerning to each percentage silicon increase in Al-Si alloys was 5.4 x 10 gm^-1 sec. The effect of vibration damping relaying on the Si contents in the Al-Si alloys was negligible. (Author)

[en] Published in summary form only

[en] Published in summary form only

No abstract available

[en] Short communication

[en] Recently Venumadhav et al. proposed a new pipeline to analyze LIGO–Virgo Collaboration’s O1–O2 data, and discovered eight new binary black hole (BBH) mergers, including one with a high effective spin, ${\mathrm{\chi <!--\; ??\; -->}}_{\mathrm{e}\mathrm{f}\mathrm{f}}$. This discovery helps to clarify the origin of the observed BBHs and the dynamical capture versus field binaries debate. Using a tide-wind model that characterizes the late phases of binary evolution and captures the essence of field binary spin evolution, we show that the observed ${\mathrm{\chi <!--\; ??\; -->}}_{\mathrm{e}\mathrm{f}\mathrm{f}}$ distribution favors this model over capture. However, given the current limited sample size, capture scenarios (isotropic models) cannot be ruled out. Observations of roughly 100 merges will enable us to distinguish between the different formation scenarios. However, if as expected, both formation channels operate, it may be difficult to resolve their exact fraction.