Forward scattering due to slow-down of the intermediate in the H + HD --> D + H(2) reaction

Quantum dynamical processes near the energy barrier that separates reactants from products influence the detailed mechanism by which elementary chemical reactions occur. In fact, these processes can change the product scattering behaviour from that expected from simple collision considerations, as seen in the two classical reactions F + H(2) --> HF + H and H + H(2) --> H(2) + H and their isotopic variants. In the case of the F + HD reaction, the role of a quantized trapped Feshbach resonance state had been directly determined, confirming previous conclusions that Feshbach resonances cause state-specific forward scattering of product molecules. Forward scattering has also been observed in the H + D(2) --> HD + D reaction and attributed to a time-delayed mechanism. But despite extensive experimental and theoretical investigations, the details of the mechanism remain unclear. Here we present crossed-beam scattering experiments and quantum calculations on the H + HD --> H(2) + D reaction. We find that the motion of the system along the reaction coordinate slows down as it approaches the top of the reaction barrier, thereby allowing vibrations perpendicular to the reaction coordinate and forward scattering. The reaction thus proceeds, as previously suggested, through a well-defined 'quantized bottleneck state' different from the trapped Feshbach resonance states observed before.     

南宁市地下水化学场分区特征及其主要影响因素

根据资料对南宁市地下水化学场进行区域划分,并研究了化学类型、组分含量的特征与规律。从工程的角度进行分析后,认为水化学场变化的同时也改变了城市建筑的基础－岩土体的性质,而导致这些改变的主要因素是人为抽水和污染。     

一类乘子算子的几乎处处收敛问题

确立了一类乘子算子几乎处处逼近的阶,并用于讨论Ｃｅｓａｒｏ平均和广义Ｂｏｃｈｎｅｒ－Ｒｉｅｓｚ平均的几乎处处收敛问题。     

自准水平激光仪光学系统研究与设计

介绍了自准水平激光仪的光学系统,并就激光器以及光学系统进行了剖析与设计,由理论分析和实验结果表明：缴光仪利用此光学系统,在激光光束到望远镜发射物镜的距离为Z02＝150m的工作范围内,其激光束直径小于15mm.     

Influence of the Process Conditions on the Formation df AOX Compounds during Wool Chlorine Pretreatment

Chlorination occurred simultaneously with oxidation when wool was treated by chlorine-containing reagents. The adsorbable organic halogens( AOX) compounds were produced by the chlorination of amino acid residues, especially tyrosine residue. The factors that might influence the reaction of dichloroisocyanuric acid (DCCA) with tyrosine residue were discussed. Higher temperature, appropriate pH value and lower concentration of chloride ion are favorable to decrease the percentage of chlorination. Determination of optimum process conditions would be helpful to control AOX compounds formation during wool chlorine pretreatment.     

黑曲霉产纤维素酶系各组分特性及酶解条件

采用正交实验法分析出黑曲霉 3.316纤维素酶系各组分最适酶解条件 ,其组合分别为 C1酶 (p H5.0 ,4 5℃ ) ,Cx 酶 (p H3.5,6 5℃ )和 βG酶 (p H4 .5,6 5℃ ) .在液体发酵条件下 ,添加质量分数为 0 .0 0 3的碳酸钙时 ,各组分酶活性最高 ,其中以 C1酶明显增高 ,Cx 酶几乎无影响 ,βG酶则明显降低 .C1和 Cx 比酶活只有在碳酸钙质量分数小于 0 .0 0 5时才有提高 ,βG酶则明显降低 .添加蛋白胨 ,C1和 βG酶的最高酶活在碳酸钙质量分数小于 0 .0 0 3时有增加 ,Cx 酶则无明显变化 .碳酸钙和蛋白胨对各组分最高酶活形成时间均无影响 .在各组分酶分泌规律方面 ,仅有碳酸钙对 C1和βG酶有一定影响     

砖混组合结构隔震房屋的地震反应

研究基础隔震砖混组合结构房屋的地震反应,利用三维有限元分析程序 得到了结构的基底剪力和层间位移。通过分析对比隔震房屋和非隔震房屋的计算结果,发现橡胶隔震垫可以减小地震对房屋建筑的作用,并且使隔震房屋产生平动位移,给出了一些有意义的结果和结论。     

瓷套式500kV氧化锌避雷器的电位分布计算及均压环设计

采用有限元－解析结合解法,对330kV和一种新型500kV氧化锌避雷器（MOA）电阻片的电压承担率进行了计算,解决了含复杂介质和导体结构的轴对称无界电场的数值计算问题,其程序设计与通用的有限元法完全相似,在330kVMOA的计算结果与实测结果取得了良好一致性的基础上,分析了影响新型结构500kVMOA电阻片的电压承担率的多种因素,并给出了电阻片的电压承担率分布较为合理的一种结构设计方案。