A direct Monte-Carlo simulation method was developed to calculate neutron yield and spectrum in (α, n) reaction. It is based on continuous collision method, using stopping power computed by the program SRIM to simulate the moderation of α-particle and the ACE format of the nuclear data library JENDL/AN-2005 to calculate the neutron yield and spectrum in (α, n) reaction. Moreover, a (α, n)-simulator was developed based on the program NPTS. (α, n) neutron yields of light nuclides obtained in our simulations are consistent with experiments. In terms of (α, n) neutron spectrum, our results are in good agreement with experiments in the cases of B, F and O targets, while deviations are present in the cases of C, Al and Si.

Left kink (LK) and right kink (RK) migration and velocity at different temperatures and shear stresses are obtained with molecular dynamics (MD) method. By means of nudged elastic band method (NEB) based on tight binding (TB) potential, migration energies of LK and RK are calculated. It shows that due to high migration energy a single LK or RK moves slowly. Multiple kink pair structure of LK and RK-reconstruction defect (RC) dissociated from RK accelerate motion of LK and RK. Particularly, RC makes 30° partial dislocation move faster.

According to the principle of a new scanning electron microscope and the mechanism of the interaction between electron beam and solid target,the trajectories of an incident electron in a sample are simulated,a simulation program is compiled using the Monte Carlo method,and the backscattering coefficients corresponding to different parameters of the SEM are obtained.

The energy band structure of TiN/VN superlattice thin film is calculated using the pseudopotential method.The total energy of the TiN/VN superlattice cell is also calculated.Then the relationship between C₄₄ and the period of superlattice λ is obtained.The superlattic period where C₄₄ reaches the maximum basically accords with the experimental data.

According to the group chain[SO(5)⊃U(1)_DⓧSU(2)_T]ⓧ[Sp(2j+1)⊃O(3)],the coupling states of j-shell nucleons are classified by D=(n-2 j-1)/2,isospin T,angular momentum J and generalized quasispin[s,t],where s is generalized siniority and t is reduced isospin;the multiplicities classified are products of SO(5)⊃U(1)_DⓧSU(2)_T and Sp(2j+1)⊃O(3) group reduction multiplicities.The explicit formulas for the two group reduction multiplicities are presented,and some results calculated are listed.

Electromagnetic wave eigenmode equation in one dimension periodic lossy medium is derived. It has been found that the solutions of the equation can be classified as a series of conduction and forbidden bands. Substituion of the real Re(K²) for complex K to symbolise modes shows the band structure clearly and facilitates classifing and comparing of the modes. The figures of the lowest two bands of TE wave and TM wave for a group of parameters are given by using numerical method. They are compared with electron energy band in periodic potential field.