Stereodynamics in reaction O（1D） ＋ CH4 〉OH ＋ CH3

A theoretical study of the stereodynamics for reaction O(1D) + CH4→OH + CH3 has been carried out using the quasiclassical trajectory method(QCT) on a potential energy surface structured by Gonzalez et al. The integral cross sections(ICSs), differential cross sections(DCSs) and product rotational angular momentum polarization have been calculated. With the collision energy increasing, the ICS decreases. There is no threshold energy, because no barrier is found on the minimum energy path. The DCS results show that the backward and forward scatterings exist at the same time. With the collision energy increasing, the dominant rotation of the product changes from the right-handed direction to the left-handed direction in planes parallel to the scattering plane. In the isotopic effect study, the decrease of the mass factor weakens the polarization degree of the rotational angular momentum vectors of the products.     

基于绿色化学理念的苯甲醛与安息香的相互转化

为了在基础教学实验中引入绿色化学理念以及强化氧化还原反应操作,本文设计了苯甲醛和安息香的相互转化实验:以苯甲醛为原料经维生素B1催化得到安息香,再用硼氢化钠还原安息香得到二苯乙二醇,二苯乙二醇用新型绿色催化剂NaMnOx氧化回到苯甲醛。通过氢核磁共振(1H NMR)对氧化还原反应的产物结构进行了鉴定,液相色谱分析结果表明氧化反应转化率达到90%以上。通过这一循环转化反应的实现,一方面树立了学生的绿色化学理念,另一方面加强了氧化及还原反应的操作训练,在进一步锻炼学生实验能力的同时,使其对化学反应的认知与评价更加完整。