Spin\|1/2 anisotropic Heisenberg chain in longitudinal external magnetic field is studied by traditional Jordan\|Wigner transformation and bosonization method.

In this paper,the Heisenberg Chain equations with periodic initial value problem is considered,an explicit finite difference scheme is proposed,and its convergence is proved by bounded extension method.

In this thesis the following Compressible Heisenberg Chain equations with periodic initial value problem is considered: An explicit finite difference scheme, the semi-discrete and fulll discrete Fourier spectral and pseudo-spectral schemes are proposeed.

In order to investigate the effects of helium on the excess point defects and secondary defects processes in low activation Fe-Cr-Mn(W, V) alloys during electron beam and electron-He+ ion dual beam irradiation, the in situ observation was carried out using a high voltage electron microscope connected with an ion accelerator.

Mixing and quenching of Cs(6P_J) states induced by collisions with He atoms and N_2 molecules;

Rb(5 P_J)+(He,N_2) collisional energy transfer;

Mixing and Quenching of Rb 5P_J States Induced by Collisions with He Atoms and N_2 Molecules;