金刚石磨粒切削运动分析及切削厚度计算

在分析金刚石锯片刀头运动轨迹的基础上，根据金刚石锯片的切削运动方程，得出了金刚石磨粒最大切削厚度的计算公式，提出了切削过程中两个新的观点：（１）单颗粒金刚石锯切掉的岩石其水平距离是不变的；（２）切削厚度是按正弦规律变化的，这给锯片设计和正确使用提供了可靠的依据     

pH effect of· OH radical induced oxidation of phosphoryl- methionine in aqueous solution

Conclusion The results of pulse radiolytical research on the · OH radical-induced oxidation of NDM in aqueous solution demonstrate that pH value has a great influence on the radiolytical mechanism of NDM. At low pH value, the product is mainly stabilization of the oxidizing sulfur centre in the three-electron-bonded cation radical NDM₂ ·⁺ [S]; with the increase of pH value, NDM₂ ·⁺ [S] gradually decays to become the reducing α-amino radical which was verified by the chemical method and whose yield was also calculated. Compared with Met₂ ·⁺ [S] produced by the · OH radical-induced oxidation in aqueous solution [1], the stability of NDM₂·⁺ [S] increases and the yield of α-amino radical decreases. This suggests that the introduction of phosphoryl group has a coordinating effect on the radioprotection of methionine to biological systems, and provides the essentially theoretical foundation for the thorough clarification of the reversible phosphorylation of proteins.     

Ab initio calculation of structure and Raman and Infrared spectra of Trifluoromethylthiosulphenyl Chloride

The molecular model of Trifluoromethylthiosulphenyl Chloride, CF₃SSCl, was presented.Ab initio method was used to calculate the structure and Raman and Infrared spectra. The results show that CF₃SSCl possess stereoscopic structure ofC ₁ symmetry with a torsional angle of 94.2°. The potential energy distribution and isotope replacement methods were applied to determine the vibrational assignment. The vibrational frequencies and corresponding modes of the molecule were obtained. The calculated vibrational frequencies are in good agreement with experiments. Supported by the National Natural Science Foundation of China Zou Xianwu: born in Apr, 1938, Professor