A laser diode pumped cesium beam frequency standard had been built. The laser diode used for both optical pumping and detection is frequency-locked at the 4-4 transition of Cs D₂ line. The Voltage controlled crystal oscillator(VCCO) frequency is locked to the center of the Ramsey pattern of the microwave clock transition after frequency multiplying and synthesizing. The preliminary measurement of the frequency stabilities shows that the results are in agreement with the theory, and better results could be achieved by further improving the frequency stability of the laser diode.

A model for high T_c superconductivity is considered. The Cu d_x²-y² electrons correlate by means of polarization-plasmon interaction. We show that when the plasmon energy approaches to the energy difference of the two bands of Cu d_x²-y², a resonant-enhanced interaction between the electrons can be realized. In this model the oxygen vacancies are responsible for the high-T_c superconductivity to which the plasmon frequency is mainly related.

The thermoelectric power in amorphous (Fe_1-xT_x)₈₄B₁₆ alloys, where T stands for V, Nb, Ta and x ranges from 0 to 0.08, is measured in the temperature range 77-350K. The results can be qualitatively understood using Mott s-d scattering model or Herzer's theory on the assumption of the occurrence of a virtual bound state near Fermi level. The differences between FeVB, FeNbB and FeTaB systems confirm the existence of a period effect in these alloys.

In laser plasma, the real experimental electron energy distribution (EED) f deviates from Druyveteyn distribution f_D. This paper suggests that the deviation (f- f_D ) of Druyvesteyn distribution, instead of EEDS, can be used to shod clearly some details of excitation and ionization of atoms(molecules), and also gives some examples of CO₂, N₂, He, Ne and Ar.

Resonant Raman scattering from GaAs LO phonons in a 59Å GaAS/20Å AlAs superlattice was studied. The relevant intersubband energies were determined. The results suggest that all of the exciton transitions from the hole subbands HH1, LH1, HH2, HH3, LH2 and HH4 to the electron subbands CB1 and CB2 in the energy region covered by our incident dye laser were observed and a justificative analysis may involve effects due to valence band mixing and to 3D electronic miniband structure.

X-ray Photcelectron Spectroscopy (XPS) was employed to study the single phase high-T_c superconductor YBa₂Cu₃O_9-δ. Comparison. Of the observed valence band spectrum with the theoretical spectrum of Mattheiss is given. The core level spectrum of Ba 3d_5/2 was examined. The results of Y₂Cu₂O₅ and Y₂BaCuO₅ are also reported.

A multiple shooting method combined with a Newton iteration for determining bifurcation curves of two-dimensional maps is presented. This method is so effective that the high period bifurcation curves which could not be estimated with any other methods can be determined. Some P8 bifurcation curves of the Henon map are calculated as an example.

Hydrogen adsorption and diffusion on the surface of austenitic stainless steel are studied with atom probe field ion microscope (AP-FIM). Hydrogen is noticeably adsorbed on the surface at low temperature (85K) and diffuses into the bulk to a depth of about 40 atom layers . The diffusion activation energy is calculated to be 0.22eV ( or 21.2KJ/mol). It is also found that the microstructure of a specimen charged with hydrogen is changed, and the distribution of hydrogen fluctuates with the depth.

The temperature dependences of the dynamic-elastic and viscous susceptibilities have been measured for Au₈₃Fe₁₇, after cold-rolling. It is found that cold-rolling reduces the Curie temperature and raises the spin-freezing temperature remarkably. These results can be explained on the basis of the precipitation medal proposed by Borg and Violet.

A new independently-produced-many-fireballs model was built up by the author. The relationship between the average number of small fireball k and s^1/2 was obtained, the multiplicity distribution was interpreted, and the q-th moment and multiplicity distribution in S^1/2 = 2TeV and 40TeV can be predicted by this model.

In this letter, we point out that the Batlogg et al. experiment does not indicate that in the oxide superconductors Ba₂YCu₃O₇ and Ba₂EuCu₃O₇, the isotope effect, if existed. would be very small, but instead, shows that the coupling between electron and the high frequency lattice vibration involving oxygen is weak.

The energy levels, En. of pions in multiparticle systems have been calculated by using the probability distribution, P(n,k), of the independent-creation model of multi-fire balls and the density matrix method of quantum statistics. The result, E_n = E₀ +nk_BTln( 1+1/n )-k_BTln x Γ(n+k) /Γ(k) Γ(n+1), shows that the nonlinear interaction depends on k. and it can take place only between different fire-balls.