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In this paper taking the case of the Computer Specialty in Newly-promoted undergraduate universities, discussed how to create a practice teaching environment for cultivating applied talents. Specifically suggested how to bulid an effectively practice teaching environment in the classroom; how to take employment as the direction to guide the training orientation of students’s practical ability and how to make good use of teaching resources to create a practice platform and so on. Those thoughts and methods proposed in this paper have some references for other specialties’s practice teaching.

We observe the phenomenon of priority oscillation of the unexpected σ-polarization in high-power Nd:YVO4 ring laser. The severe thermal lens of the σ-polarized lasing, compared with the π-polarized lasing, is the only reason for the phenomenon. By designing a wedge Nd:YVO4 crystal as the gain medium, the unexpected σ-polarization is completely suppressed in the entire range of pump powers, and the polarization stability of the expected π-polarized output is enhanced. With the output power increasing from threshold to the maximum power, no σ-polarization lasing is observed. As a result, 25.3 W of stable single-frequency laser output at 532 nm is experimentally demonstrated.

Dimensionless dispersion curve equation of one-dimensional periodic structure with three oscillators is deduced. It is proved by singularity theory that the topology of the dispersion curves does not change with mass and stiffness parameter. Then the equations of initial and final frequencies of the bands are presented. The method of band gap design is gained consequently. Two examples i.e., the system with the same stiffness and the system with the same mass, are given to verify it. The method may provide the reference for designing the band gap of the photonic and phononic crystals.

Small-angle X-ray diffraction study of amorphous a-Si:H/(a-SiNx:H) periodical multilayer thin films and some single layer films has been undertaken. A number of satellite peaks were found in the lower side of Bragg diffraction peaks of multilayer thin films with a less number of periods. A number of diffraction peaks were also found for the small-angle diffraction of single layer films. We have presented a simple formula for calculating the X-ray diffraction intensity of multilayer and single layer films. A satisfactory explaination of experimental results was obtained. Consequently, a simple method for measuring the total thickness of both multilayer and single layer thin films has been presented.