催化作用

This paper is focused on the preparation, characterization of metal clusters and theircatalytic performance in the enantioselective as well as stereoselective hydrogenations. It iscomposed of the five parts as follows: Chapter 1 A review was given on the two most studied enantioselective systems—Ni/TA and Pt/cinchona system, including some recent progress.

本论文研究了铂、铱纳米金属簇在α-酮酯、α-二酮不对称氢化中的催化性能及金属离子在α-二酮立体选择性氢化中的修饰作用，主要分为以下几部分：第一章对多相不对称催化体系一Ni／TA和Pt／cinchona及其一些最新进展作了较系统的评述；同时简要介绍了纳米金属簇的特性及其在催化中的一些应用。

We study the relation between the BET and the efficiency. Then, the reasons of the deactivation are introduced.

文章首先研究了我国催化转化器的构成以及作用机理，分析了催化器比表面积对催化性能的影响。

It has been observed that pyrocatechol and m-phenylenediamin can sensitively inhibit the discoloration of neutral red oxidation by the H2O2 and in the presence of catalyzer Fe in dilute sulfuric acid solution but the inhibitory effects of two organic compounds can not be added. Based on this research, the advantages of artificial neural network were adopted to handle the experimental data and a new inhibitory kinetic spectrophotometry of simultaneous determination for pyrocatechol and m-phenylenediamin with artificial neural networks was established.

在硫酸性介质中，Fe能够催化H2O2氧化中性红褪色反应，邻苯二酚和间苯二胺都能阻抑该催化氧化褪色反应的速度，研究发现：两者对Fe催化H2O2氧化中性红褪色反应阻抑作用不具有加和性，根据这一现象，用人工神经网络处理非线性体系的优势进行数据处理，从而建立了一种新的测定邻苯二酚和间苯二胺混合物的人工神经网络阻抑动力学光度法。

The results showed that the application of photocatalytic oxidation to the treatment of wastewater was feasible and efficient, but it was affected by the operation conditions.There existed optimum value of the dosage of catalyst, initial benzamide concentration and pH value for the photocatalytic oxidation performance.H2PO-4,Cl-, Cu2+ and Al3+ showed obvious inhibition to the photocatalytic oxidation.

结果表明，循环式浆态光催化反应器中光催化剂的用量、污染物的初始浓度和初始pH值对模拟污染物光催化降解性能的影响存在适宜值；体系中H2PO-4、Cl-、Cu2+、Al3+对其光催化降解过程有明显的抑制作用。

The degradation experiments of benzamide by photocatalysis and electrically assisted photocatalysis demonstrated that the extra electric field had the obvious assistant effect on photocatalysis and the benzamide degradation rate by EAP was much higher than that by photocatalysis. When the electrode potential of photocatalyst was -0.05V/SCE, the removal efficiency of benzamide could be 95% in 120min.

苯甲酰胺降解试验表明，外加电场对光催化氧化技术具有较强的辅助作用，电助光催化氧化技术的处理效率远远高于光催化氧化技术，当施加的电极电位为-0.05V时，苯甲酰胺在120min时的去除率可达95%。

The system exhibits favorable catalytic activity for the oxidation of benzylic and allylic alcohols, in spite of low activity observed for the oxidation of heterocyclic and aliphatic alcohols.

探讨了TEMPO-IL/CuCl催化体系的催化机理，铜离子是反应的活性中心。针对 TEMPO/CuCl 催化体系反应速度较慢的问题，研究了碱对 TEMPO/CuCl 体系的促进作用。

Reaction trends of catalytic desulfurization of thiophene were determined based on the reaction energy needed, which was obtained with the AM1 calculation results of thiophene and possible carbonium ions on transition state.

采用半经验AM1计算方法，利用静态理论对噻吩在分子筛催化剂上的催化裂化脱硫机理进行了量子化学计算研究，通过对噻吩分子和可能产生的中间正碳离子的量子化学计算，得到各中间反应所需的能量，从而判断噻吩催化裂化脱硫反应的趋势，证实了氢转移反应在催化裂化脱硫中所起的作用。

The conducting wall in micro-tube preheats the inlet mixture by axial heat transfer. The existence of conducting wall will help to reach full reaction in the micro-tube. As the inlet velocity increases, both the existence of the surface catalytic combustion and the gas phase combustion become the limiting factors on combustion. Wall material and equivalence ratio of hydrogen/air mixture have important influence on catalytic combustion of hydrogen.

计算结果表明：表面催化反应对空间气相反应有抑制作用；在微型管道内，通过导热壁轴向间的传热，预热入口混合气体，使氢气燃烧更加充分；随着入口速度的增大，燃烧过程同时存在着表面催化反应和空间气相反应两种控制因素；管壁材料和当量比对氢气的催化燃烧过程有重要的影响。

Ferric chloride catalyzed direct conversion of carbonyl compounds to the corresponding chloride with silicon hydride ( dichloromethylsilane , chlorodiphenylsilane or trichlorosilane) was realized.

在甲基二氯硅烷作用下，FeCl3能催化羰基化合物的还原氯代反应，得到相应的氯代产物；在甲基二氯硅烷、PBr3或NaI作用下，FeCl3可以催化羰基化合物的还原溴代或碘代反应，分别以良好的收率得到相应的溴代烷或碘代烷

By means of the plating technology and the system designed and made ourselves, we call them as the direct-heat evaporating roll-pulled with vacuum piston and the helix evaporating of straight heat-wire with the negative thermal specific resistance , the align polishing ring films and the separating ones of pure gold have been plated directly at the inner wall of the capillary of Sealed-off CO〓 laser.

简便有效地使器件的输出功率、光束品质、稳定性和使用寿命都得以提高的作用效果；分析了放电驱动催化机理及催化效果与器件参数、工作状态及其中的等离子体过程的对应关系，建立了数学模型，编程数值计算了放电管内正柱区中等离子体参数分布及其与器件工作外参数的关系；利用我们设计开发的直热式真空活塞卷拖和负阻直热丝螺旋蒸镀工艺及制作的系统，在封离型CO〓激光器毛细管玻璃内壁上直接镀制出了单质金的镜面环膜和离散膜，经理论分析和实验检验，指出美国专利4756000号的环金方案将导致器件工作特性的改变和恶化，降低效率；肯定了正柱区边界部分场对建立良好的激光振荡的作用意义，明确提出了①作为高品质器件设计基础的弥散膜催化剂；②高斯管型弦驻波振动定型磨制、检测的新概念及相应的制备加工工艺；实际制出了管子，测定了其基本的工作特性和初期过程。

She gently rebuff ed him, but agreed that they could be friends

她婉言拒绝了，但同意作为朋友相处。

If in the penal farm, you were sure to be criticized.

要是在劳改农场，你等着挨绳子吧！