A method is presented by which an infinite series of new dual solution pairs of cylindrically symmetric vacuum Einstein equations can be generated. A new cylindrical gravitational wave solution is given and discussed.

The scale dependence of the three-generation phase-invariant measure of CP nonconservation is revealed by solving the coupled renormalization group equations. Employing a careful calculation scheme, we find the CP nonconservation measure, contrary to the previous studies, decreases with energy.

Nuclear core polarization processes in the Ovββ decay of ⁴⁸Ca are discussed in a diagrammatic effective operator approach. The main effect of these processes is to increase the limit on heavy neutrino mass of about 8%.

Sever and Tezcan recently [Phys.Rew.A36(1987)1045], used the 1/N expansion to solve the time independent Schrodinger equation with a more general scrcened Coulomb potential; V (r) = -(a/r)[l + (1 + br) exp(-2br)] obtained the analytical expressions, and gave some numerical values of energies for 1s and 2s states. We apply the shifted 1 / N expansion to solve the same Schrödinger equation and calculate the numerical values of energies for 1s to 5g states. Our results for 18 and 2s states are excellent agreement with those obtained by solving the Schrodinger equation by means of the numerical calculation method, and the accuracy is much better than the results of Sever and Tezcan.

Two new model equations which we call a higher order cylindrical KdV equation and a higher order cylindrical KP equation are proposed when we consider the 2-dimensional modulation of water waves with surface tension in cylindrical coordinate system. Some exact (2+1)-dimensional solitary wave solutions have been obtained by relating them to the higher order KdV equation through an appropriate variable transformation.

The phenomena of bifurcation, chaos and hysteresis of electrodynamic cone loudspeaker have been investegated experimentally in mid-frequency range. The frequency spectrum, as well as the phase diagram in frequency-voltage phane, of bifurcation and chaos is given. The hysteresis phenomenon is observed clearly from frequency response curve.

Based on the authors' former work, a study on reflection and refraction of finite-amplitude sound wave was carried out. A solution completely satisfying the continuity conditions was obtained by means of the method of making the inhomogeneous terms of the wave equation to be determined.

Empirical linear combination of atomic orbitals (LCAO) calculations are performed to investigate the electronic structure of Sb₂Se₃, Sb₂Te₃, In₂Se₃ and In₂Te₃. The bands of bonding p states are overlapped with the bands of lone pair states in these materials. The absorption edges of these materials correspond to indirect gap, and the calculation agrees with experimental values.

Influence of nitrogen content on electron spin resonance (ESR) in a-Si:H/a-SiN_x:H multilayers is studied, associated with infrared absorption analysis. The spin density decreases rapidly in the region x>~ 0.7 and approaches a saturated value, which is much less than common assumption. The results are explained in terms of the structure relaxation due to the increase of N-H bonds with increasing x and the transfer doping across interfaces.

A new theoretical interpretation for the anomalous quantum size effects in PbTe-Bi superlattices has been proposed. The calculated thickness of Bi layers at which the semimetal-semiconductor transition occurs is in good agreement with the experimental data.

At the transition from normal to superconducting states there were anomalies of ultrasonic attenuation in single-phased specimens Bi_2-xPb_x Sr₂ CaCu₂ O_y ( T_cmid=80K); and as the temperature was lowered below T_cmid, the attenuation decreased rapidly. At the temperature about 135K there was a relatively high peak, which may be due to a certain relaxation process.

The magnetization curves at 1.5K and Curie temperature of amorphow (Fe_100-xB_x)₈₈ Nd_12±ε alloys were measured. Their spontaneous magnetizations is explained by a noncollinear structure. The average magnetic moment μ_Fe per Fe atom decreases monotonically with increasing x, and becomes more rapid when x > 24. The B content dependence of Curie temperature shows a mazimum at x = 15. At x< 15, the increase of T_c with x may be attributed to the indirect exchange interactions between Fe-Fe atoms.

The domain-wall resonance(DWR) frequencies of stripe lattices in the garnet films, as a function of the in-film magnetic field H_p, have been measured. The samples were grown by liquid, phase epitaxy(LPE) ,on (111) GGG substrates. The experiments were carried out with the h.f. magnetic field parallel and perpendicular to the stripe domains, respectively. In addition, as the applied magnetic field was rotated out of the film gradually, the variation of the DWR frequencies was also investigated.