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The main research work of this dissertation is as follows: Based on the chemical reaction engineering theory and the nitrobenzene electroreduction mechanism, the plate and frame electrolyzer was designed and applied to the process of electroreduction nitrobenzene to p-aminophenol. This dissertation measured the residence time distribution data of the electrolyzer by means of the pulse response method and studied the rule of flow pattern along with the current capacity change. Under different conditions ,this dissertation studied the cyclic voltammetry properties of nitrobenzene on different electrodes by means of the dynamic cyclic voltammetry method and the electrode materials applied to the NB electroreduction have been selected primarily.Baseed on the results of cyclic voltammetry tests, this dissertation used p-electrode systems to measure the steady-state- polarization curves of nitrobenzene on different electrodes in H-type diaphragm cell, and obtained each primary factor s influence rule and the exchange current density value of each electrode.And then on the basis of the conclusions of fundamental researchs upword, the effects of influence factors on the the yield of p-aminophenol and the current efficiency,such as electrode material, current density, quantity of electricity circulated, nitrobenzene concentration . sulpuric acid concentration and so on, have been studied in detail in the systems of hign temperature , strong acidity and oxygen-poorthrough a series of electrolysis experiments in this paper.After all using Pb as anode Monel metal as cathode Dupont Nafion 417 cation-exchange membrane as membrane, this dissertation obtained the optimum technological condition: reaction temperature about 85C, current density 500A m-2, sulphuric acid concentration 20%wt.

论文的主要研究工作为：运用化学反应工程理论，结合硝基苯的电还原机理，设计出用于硝基苯直接电还原合成对氨基苯酚实验的板框式电解槽，并利用脉冲响应法测定了该板框式电解槽的停留时间分布数据，研究了流型随流量变化的规律；通过动态循环伏安法研究了硝基苯在不同电极上、不同条件下的循环伏安特性，初步评选出了用于硝基苯电还原的电极材料；结合循环伏安的测定结果，在H型隔膜电解槽中采用三电极体系测定了硝基苯在不同电极上、不同条件下的稳态极化曲线，得到了各主要因素的影响规律及硝基苯在各个电极上电还原的交换电流密度数值；在基础研究结论指导下，采用板框式电解槽，在高温、强酸、贫氧系统中，进行了一系列的电解实验，分别考察了电极材料、电流密度、通电量、硝基苯浓度、硫酸浓度等因素对收率及电流效率的影响，最终选择以蒙乃尔合金电极作为阴极、铅合金为阳极、Dupont Nofion 417阳离子交换膜为隔膜，得到由硝基苯直接电还原制对氨基苯酚的最佳电解工艺条件：反应温度85℃，电流密度500A·m~(-2)，硫酸浓度20％wt。

The abscissa of the concentration convergence equals to the changes in the desorbed free energy of 1mol pure organic solvent, while that of carbon number convergence equals to the negative free energy change of its end group of the homologue, when the concentration of organic solvent is one tenth in the mobile phase.

浓度收敛点的横坐标是1mol纯溶剂的解吸附自由能；而碳数收敛点的横坐标为当流动相中有机溶剂的浓度为纯有机溶剂浓度的十分之一时的同系物端基的保留自由能的负值。

The results show that the optimum mole percent of Al3+ to Yb3+ is 9—11 for high concentration of ytterbium-doped silica-based fiber at which low concentration quenching probability, high absorption coefficient and proper numerical aperture can be obtained.

揭示出在高掺Yb3+的石英基光纤中，共掺Al3+的摩尔浓度为Yb3+摩尔浓度的9—11倍时既可以减小Yb3+的浓度猝灭概率，又可以获得高吸收系数，同时还可更好地满足数值孔径的要求的结论。

It was shown that the improvement of electric properties in 1%Eu-PZT can be attributed to Eu donor doping, which decreases the concentration of defects such as oxygen vacancies and holes, while the degradation in fatigue and leakage current properties shown in the films with more than 1mol% Eu dopant results from the apparently dominant acceptor doping, which increases the concentration of oxygen vacancies and holes.

结果表明，1mol％Eu施主掺杂，可以减少氧空位以及空穴等缺陷浓度，因此1％Eu-PZT薄膜的极化疲劳和漏电流特性得到明显改善；高于1mol％Eu的受主掺杂作用使薄膜中氧空位以及空穴等缺陷浓度增加，导致PZT薄膜电学性能恶化。

The concentration of antibody is 1:600,the 1:400 dilution of antigen is 160 mU/mL,the suitable resule of enzyme is 1:3000.The range of the kit is 5～160 mU/mL,sensitivity is 0.46mU/mL,recovery of the high and low concentration are 106.74%and 104.78%,accuracy rating is 38.982mU/mL,stability is perfect, variation is less than 15%.

本试剂盒的范围为5～160 mU/mL，足以包含正常范围6～25mU/mL；灵敏度为0.46mU/mL；高浓度样品平均回收率为106.74%，低浓度样品平均回收率为104.78%；准确度为38.982mU/mL；稳定性良好；精密度实验结果显示，批内变异＜10%，批间变异＜15%。

The results indicate that the acetophenone conversion is affected orderly by substrate concentration, reaction time, reaction temperature and yeast concentration.

结果表明，影响苯乙酮转化率的因素依次为底物浓度、反应时间、反应温度和酵母浓度，影响1苯基乙醇对映选择性的因素依次为反应温度、底物浓度、酵母浓度和反应时间。

The effects of some factors, such as reaction temperature, reaction time, substrate concentration and yeast concentration, on the acetophenone conversion and- 1-phenylethanol enantioselectivity were investigated by orthogonal experiments.

研究了酵母细胞催化芳香酮的不对称还原反应，采用正交试验综合考察了反应温度、反应时间、底物浓度和酵母浓度等因素对底物苯乙酮转化率和产物1苯基乙醇对映选择性的影响。

It wasfound that the kinetics formulas of these photo-polymerization systemsdeviated from the normal kinetics formula sharply and there existed acritical concentration of 〓, the reaction rate would descendwhen the concentration of 〓 exceeded it.

我们发现这些光聚合反应的动力学方程与正常的动力学方程偏离较大；并首次报道了当〓的浓度达到某—临界值时，反应速率随着〓浓度的上升反而下降的现象。

To decrease maufacture costs and improve the ratio of efficiency and outlay.The not exensive emulsifier, hydrophobe and other adminicle were mixed with self-made polyesters, siloxane-polyester copolymers to obtain defoamers which be better than imported.And the factors in the process of compound were studied particularly and systemically.the prime project is as follows:the siloxane-polyester copolymer is synthesized with PPG2000,PEG400,1% hydrogen-containing Polyhydrosiloxanes, hexane diacid,which mol ratio of materials is 7:3:6:5.emulsifying agents are SP-60 and tw-60,the value of HLB is 8.5.its dosage is 5%.the concentration of control- bubble resin is 5%. the concentration of liquid hydrocarbon A is 20%.

为进一步降低消泡剂的生产成本，提高其使用时的效费比，采用价格低廉的乳化剂、疏水剂及其他助剂与所制聚醚酯、有机硅改性聚醚酯进行复配，制取了性能优于进口产品的优质消泡剂；并对复配工艺各要素进行了详细、系统的研究；最佳配方为：PPG2000、PEG400、含氢量1%的硅油，己二酸以物质的量之比为7：3：6：5制成的有机硅改性聚醚酯，乳化剂选择SP-60/TW-60组合、HLB值为8.5、用量5%，抑泡树脂用量5%，液态烃A用量20%，液态烃B用量10%，疏水剂用量15%～20%。

L^(-1), the growth of callus was inhibited. However, the effect of Carbenicillin on callus was little and the differentiation of adventive buds was promoted under appropriate concentration. When the Carbenicillin's concentration was 200mg?

L^(-1)时，愈伤组织生长受到抑制；而羧苄青霉素对愈伤组织影响很小，在适宜的浓度下能促进不定芽分化，213品种在羧苄青霉素浓度为200mg？

So it was last week in Selma , alabama.

上星期在亚拉巴马州塞尔马市发生的事件也是这样一个转折点。

The group also spearheads various social programs in China.

该组织还带头参与中国的各种社会活动。