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ZnO materials have being researched in recent 30 years as a hot topic. ZnO is a third generation of semiconductor, it can be prepared into various forms of films and nanostructures, and they have excellent optical properties, electrical properties and magnetic properties. Because the polar ZnO’s quantum wells have a strong electric field, this will have a great impact on its optical properties. But non-polar ZnO has reduced such a strong electric field, so it greatly improved the luminescent performance. It’s more excellent than polar ZnO in the optical performance. In recent years, non-polar ZnO thin films’ research became increasingly evident. This article summed up the performances, preparations and applications of non-polar ZnO, and there are some suggestions. All of these are good to the further study of non-polar ZnO.

Compound semiconductor GaAs crystal was grown by the pulling-down method and the Φ2" GaAs boules were obtained. The growth defects, such as growth stripes, small facets, pits and dislocations, were observed. The pits on the surface of the boule was attributed to the water content of B2O3 encapsulant and the growth defects on the tail were associated with the evaporation of As due to GaAs decomposition. The average EPD (etch pit density) was measured less than 5000 cm-2, which shows the pulling-down method was a potential technique to grow high quality GaAs crystals.

As a professional with strong theoretical and practical in a new college, the guidance major-materials science and engineering involves extremely broad field. Our reform ideas and practices are only to training science-based applied talents possessing engineering capabilities. Facing the new situation on the demand for materials engineering personnel, we reform curriculum and teaching to get rid of the drawbacks of the original content and build the professional training program with the characteristics and course system.

11 oxides (MgO, CaO, BaO, TiO 2 , V 2 O 5 , MnO 2 , Fe 2 O 3 , CuO, ZnO, PbO 2 and B 2 O 3 ), often found in coal-derived carbon materials, were loaded into the coal-derived carbon material by two methods such as adsorbing oxides through solution onto the surface of coke and adding oxides into the coal before carbonization. The effects of oxides on carbon solution reaction of carbon material were investigated and compared. The results show that the effect trends are similar but the effect of oxides by adsorbing is remarkably greater than that of the oxides by adding oxides as BaO, MgO, Fe 2 O 3 , CuO, ZnO, MnO 2 , PbO 2 and B 2 O 3 . And the effect trends are similar. BaO, CaO and Fe 2 O 3 are the greatest affecting oxides. The saturation point of addition content is 3% and that of adsorption is 1%.