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The analyzed results about the forming mechanism of TiC indicate that the dendritical TiC is the primary TiC which freely grows in a continuous growth way in supercooling liquid metal before the peritectic reaction, and the short bar-like TiC nucleates and grows in β—Ti after peritectic reaction.

在对TiC形成机制的分析中认为，树枝状TiC是包晶反应之前过冷熔体中，以连续生长方式自由生长而成的初生TiC，而短棒状TiC则是包晶反应后在β-Ti的内部生核并长大而成。

The cracking reaction of Ethylidene diacetate is the key step to manufacture vinyl acetate from C1 compound. The technological development is based on the study of the reaction property and the reactor, and is guided by the process simulation results.

二醋酸亚乙酯裂解反应是C1路线制醋酸乙烯的关键步骤，其工艺的开发离不开反应过程的研究和反应器的确定，而过程数学模拟可以指导过程开发。

The two rate equations fitted the experimental data well,as was confirmed by the reaction of bis(4-carboxyphenyl)phenyl phosphine oxide with ethylene glycol under constant reaction temperatures of 180197℃ and at different ratios of diol to diacid,whose rate constant and activation energy were calculated.

将这两个速率方程应用于双苯基氧化膦与乙二醇的恒温自催化聚酯化反应，计算值与实验数据相一致，并计算得到了该反应的速率常数和活化能。

The use of carbon monoxide from coal or natural gas to produce dialkyl oxalate is an important research area in C1 chemical technology. The chemical reactions and performance in the coupling reaction system for synthesis of diethyl oxalate from carbon monoxide and ethyl nitrite were tested in the presence of hydrogen under the typical coupling reaction conditions.

摘 要：实验研究了在氢气存在下，一氧化碳与亚硝酸乙酯偶联合成草酸二乙酯反应体系在典型操作条件下的化学反应和反应性能，结果表明氢气只与反应体系中的亚硝酸乙酯反应生成乙醇。

This work, concentrated on the asymmetric allylation of aldehydes controlled by different chiral auxiliaries prepared from rotational pure tartaric acid, can be divided into three parts.The first part aims to review the developments of chiral drugs and asymmetric synthesis, from which derived the present research topic backgrounds and works.Synthesis and applications of allylation from aldehydes are the second part of the thesis. By optimizing the reaction conditions, such as solvents, temperature, time and chiral auxiliaries like N,N\'-dibenzyl tartamide, N,N\'-p-dimethylphenyl tartamide, N,N\'-o-dimethylphenyl tartamide, N,N\'-o-dichlorophenyl tartamide, N,N\'-a-dinaphyl tartamide, N,N\'-dicyclohexyl tartamide and N,N\'-diphenyl tartamide, ideal experimenttal conditions are obtained according to HPLC monitoring, as well as the auxiliaries\' recoveries experiments. Starting from benzaldehyde and 3-bromopropaldehyde, N,N\'-dibenzyl tartamide is considered the best auxiliary in this reaction.

本文介绍了醛的不对称烯丙基化反应，以光学纯酒石酸为原料，研究了不同构型手性配体在醛的烯丙基化反应中的立体选择性，全文共分三部分十个章节：第一部分对当前手性药物和手性技术进行了概述，并由此展开了本文的研究背景和任务；第二部分为有机合成部分，对醛的不对称烯丙基化反应进行了深入探讨，以苯甲醛为原料对反应条件进行优化，在优化的反应条件下对制备的七种可回收手性酰胺配体(N-苄基酒石酸二酰胺、N-对甲苯基酒石酸二酰胺、N-邻甲苯基酒石酸二酰胺、N-邻氯苯基酒石酸二酰胺、N-a-萘基酒石酸二酰胺、N-环己基酒石酸二酰胺和N-苯基酒石酸二酰胺)进行筛选，优化配体回收实验条件，最终确定出N-苄基酒石酸二酰胺在苯甲醛的不对称烯丙基化反应中具有较大优越性，结晶回收的手性配体光学纯度保持不变。

The result of study on the apparent kinetics of photochlorination of acetic acid showed that the reaction rate is comparatively slow and the byproduct of dichloroacetic acid is created during the reaction. In order to put the technology of photochlorination of acetic acid into industrialization, the new technology about distillation column with a single reactor having a large reactive potency must be adapted.

由乙酸光氯化反应宏观动力学研究结果可见，反应速度相对较慢，且生成二氯乙酸副产品，为了乙酸光氯化工艺实现工业化，必须采用具有较大反应能力的反应与精馏耦合工艺。

The UV and IR spectroscopic studies of the monomer films showed that the photoreaction ratio of monomer (about 50%) was higher than the corresponding photosensitive polymer (about 10%, PVCi). The polarized IR spectra proved that obvious anisotropic absorption was displayed in the irradiated photosensitive film. With polarizing microscopy method, we found that these kinds of photoalignment films exhibited good alignment ability, and the stability of the photoalignment film could reach about 100℃. 2 A photosensitive self-assembled monolayer was fabricated that contained photo-cycloadditable groups, such as, coumarin and cinnamate. The reaction process were detected by contact angle method because the IR absorption of monolayer was very weak. The photosensitive self-assembled monolayer promote uniform alignment of nematic liquid crystals by LPUV, and it thermal stability could reach about 130℃. 3 A cationic bolaform amphiphiles was synthesized that had two photosensitive double bonds, and can be polymerized by ultraviolet. A layer-by-layer self-assembled deposition film was prepared in aqueous solution by using this material and poly (sodium 4-styrenesulfonate). The UV-Vis. spectra proved that the multilayers film was uniform and layer-by-layer. When LPUV irradiated the film, the photopolymerizable double bond underwent [2+2] cycloaddition, and the production of the reaction distributed along the polarized direction of incident LPUV. Polarized UV-Vis. spectra indicated that the irradiated self-assembled multiplayer film was anisotropic, and the dichromic ration is about 0.09, it is higher than the spin-coating method of photosensitive polymer or monomer. We used this anisotropic film as alignment layer of nematic liquid crystals, and obtained a uniform and stability alignment result, the static contrast ratio is about 100, which is very close to application of liquid crystal device. This thesis is an instance that the photochemical material was used in the physics region of liquid crystals, the route that was from photosensitive monomer, self-assembled monolayer film to self-assembled multiplayer film was undergone, by this logical research method photoailgnment of liquid crystal was extended and consummated.

围绕上述思路开展了如下工作：1合成了三种可进行光二聚反应的光敏小分子单体，LPUV 辐照制作了光控取向膜；用紫外-可见光谱法和红外光谱法分析了薄膜中的光化学反应，发现小分子的光反应程度可达到50%以上，至少比光敏高分子高出5倍；薄膜的偏振红外光谱证实，经过LPUV 辐照后薄膜出现了明显的各向异性；将小分子光控取向膜制成液晶器件，在偏光显微镜下观察看到均匀一致的液晶取向；并且热稳定性达到100℃左右，接近实用化要求。2制备了含肉桂酸、香豆素基团的自组装单层膜；采用接触角的方法监测自组装反应的动力学过程；紫外-可见光谱证实了自组装单层膜在石英基板表面形成；自组装单层膜经LPUV 辐照后能诱导液晶均匀取向，而且热稳定性可达130℃，热稳定性进一步提高。3合成了含有光敏双键的双季铵盐，在水溶液状态下将它和聚乙烯基苯磺酸钠沉积生成layer-by-layer 自组装多层膜，紫外-可见光谱证实这是一个逐层均匀的沉积；在LPUV 照射下，自组装膜中的光敏双键按照偏振方向发生[2+2]环加成反应，形成取向膜，用二向色性值评价的分子取向度高于高分子及小分子光控取向膜的水平；实验证明用自组装多层膜制成的液晶器件亮暗态均匀，静态对比度约为100，达到实用化器件的水平。

The first asymmetric total synthesis of coumarinolignoids Daphneticin and it's enantiomer was accomplished starting from 7-hydroxycoumarin and 3, 4, 5-trimethoxybenzaldehyde, in which Sharpless asymmetric dihydroxy reaction was used to construct chiral center, and Mitsunobu reaction was used to obtain desired configuration.

并以7-羟基香豆素和3，4，5-三甲氧基苯甲醛为起始原料，用Sharpless不对称双羟化反应构筑手性中心，用Mitsunobu偶联反应作为关键步骤，合成了手性的香豆素木脂素Daphneticin及其异构体。

We succeeded in synthesizing two different segments: C〓-C〓 and C〓-C〓, employing Sharpless dihydroxylation reaction, Julia coupling and samarium diiodide mediated reaction as the key steps.

我们从单保护的1，3-丙二醇出发，以Sharpless不对称双羟化反应，Julia偶联反应以及SmI〓参与的反应为关键步骤，经过艰苦的多条合成路线的尝试与探索，成功的得到了Phorboxazole A B的两个不同的边链部分C〓-C〓和C〓-C〓。

Single-component samarium diiodide catalyst system was first used with polymerization of acrylonitrile. Adding of hexamethylphosphoramide could greatly improve reaction activity of the catalyst system. AN/Sm12 and l{IVIPA1 Sm12 molar ratios, reaction time and temperature were mainly investigated with yields and molecular weights of resultant PAN.

研究发现HMPA的加入可以极大地提高催化活性；考察了单体与催化剂(SmI2)的摩尔比例、第二组分与催化剂(SmI2)的摩尔比例、反应温度、反应时间等因素对相应聚合物的产率和分子量的影响，通过对聚合物的红外和核磁的分析，提出了&单电子转移-双阴离子引发&机理。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。