氢

Starting from chiral proline, pipecolinic acid, piperazine-2-carboxylic acid and 1,2-diphenyl amino alcohol, a series of structurally simple and easily prepared amides were developed as highly effective Lewis basic organocatalysts for the asymmetric reduction of imines with trichlorosilane as the reducing agent, which promoted the reduction of N-aryl imines with high yields and excellent enantioselectivities with an unprecedented substrate spectrum.

本文分别由手性脯氨酸、哌啶酸、哌嗪酸以及氨基醇出发，设计和合成了一系列结构新颖、合成简便、性能优良的酰胺类有机小分子路易斯碱催化剂，以廉价的三氯氢硅为氢源，用这些催化剂催化亚胺不对称还原，得到了非常优良的收率、对映选择性和前所未有的底物普适性。

These kosmotropes may be divided into two groups which act somewhat differently:(1) polyhydroxy compounds fit in well with the hydrogen bonding arrangements, but stabilize any cluster 'flickering' via hydrogen bond rearrangement, as their hydroxyl groups are similarly separated to water-water separations, and (2) zwitterions where the balance between hydrophilicity, hydrophobicity, anionic and cationic characteristics ensures good solubility but only weak net interactions to surrounding water.

这些kosmotropes可分为两个群体行为稍有不同：(1)多羟基化合物符合了氢键安排但任何稳定集束'摇曳'经由氢键重排，由于其羟基同样隔开水水离职，(2)氨基酸的平衡，亲水性，疏水性，阴离子和阳离子特色ensures溶解性好，但只有弱相互作用网，对周围的水。

The best catalytic activity and selectivity could be found in the prepared catalyst system with the optimum combination of the ionic liquid, nano-Pd, and support. The stabilizer is also used to prevent the aggregation of nano-Pd particles. One of the advantages of this approach is that the prereduction of catalyst is not required.

其中离子液体、奈米钯金属及担体皆有其功能，三者之组合才能达到良好之效果，同时，在合成奈米钯过程中，必须使用稳定剂以避免奈米钯金属之聚集此触媒系统之另一优点为不需先加氢还原处理，耐水性强且可重覆使用，是一种颇具潜力之选择性氢化触媒。

It is observed by in situ stain that LDH(1-5)… nNAD+ can probabl y enter the nucleopore and bind specifically with the gene that encodes itself.

摘 要：原位染色发现，LDH(1-5)…nNAD+(LDH：乳酸脱氢酶，NAD+：氢化型辅酶I)可以进入核孔，可能与自己编码基因特异结合。

In an embodiment, the selective hydrogenation catalysts of this disclosure are used in the hydrogenation of highly unsaturated hydrocarbons such as for example and without limitation acetylene, methylacetylene, propadiene or combinations thereof.

在实施方案中，本公开的选择性加氢催化剂被用于高度不饱和烃的加氢中，其中所述高度不饱和烃例如但不限于乙炔、甲基乙炔、丙二烯或它们的组合。

The main objective of this research project is to modify the Methyl-Acetylene/propadiene selective hydrogenation reaction system of the No.3 Naphtha Cracker in CPC. The original gas phase reaction system was redesigned to a liquid phase reaction so that higher propylene selectivity was achieved and lower rates of propane and green oil were produced. To recover effectively the higher production of valuable propylene from the reaction system, the following fractionator was also redesigned.

本研究之目的在於修改中油公司三轻工场老旧的甲基乙炔／丙二烯选择性氢化气相反应系统，使成为液相反应系统，藉由液相反应的优异性，提高由MAPD氢化得到丙烯之选择率，同时降低丙烷及绿油产率，以增加丙烯产率，另亦修改丙烯精馏系统，以提升蒸馏塔提纯之效率。

The effect of silicon atom in substrate on the reaction rate and the stereoselectivity of enzymatic reactions was revealed by comparison of horse liver alcohol dehydrogenase-catalyzed stereoselective dehydrogenation of the three isomers of acetyltrimethyl propanone and their carbon analogues in aqueous/organic biphasic systems.

本项目通过对比在水－有机溶剂两相系统中，马肝醇脱氢酶催化三甲基硅烷丙酮的三个异构体及其碳类似物的光学选择性脱氢反应，揭示了底物中的硅原子对酶反应速度、立体选择性的影响规律，成功地合成了高对映体纯度的手性有机硅醇，并实现了辅酶的再生。

METHODS Chlorodehydromethyltestosterone was synthesized from methyltestosterone by cycloxidization with hydrogen peroxide to obtain cycloproxene methyltestosterone, which subjected to chloridization with was hydrochloric acid in the presence of propanone to obtain chloromethyltestosterone, and then was subjected to dehydrogenation with DDQ using PTS as dehydrogenation catalyst in benzene.

以甲睾酮和H2O2环氧化反应得到环氧甲睾酮，再与盐酸在丙酮溶媒中进行氯化反应，得到氯甲睾酮，最后用2，3-二氯－5，6-二氰基对苯醌在PTS催化下脱氢得到脱氢氯甲睾酮。

Propargyl alcohol was protected by dihydrophran with the catalysis of PPTS ,and then reacted with Ethyl Mag bromide to prepare its corresponding Grignard reagent.

炔丙醇在 PPTS 催化下由二氢吡喃保护，与溴乙烷格氏试剂反应生成相应的格氏试剂，然后与氯甲酸甲酯反应得到羟基丁炔酸甲酯四氢吡喃醚，在 PPTS 催化下脱保护后进行甲磺酰化，由溴化钠进行溴取代后合成了4-溴-2-丁炔酸甲酯，总收率达53%。

A series of pyridazino[3,2-c]1,2,4-triazoles were synthesized from hydrazides and 3-aryl-6- chloro pyridazine s (3a～3d), which were obtained from substituted benzene and succinic anhydride by Friedel-Crafts reaction, cyclization with hydrazine hydrate, dehydrogenation and chloro-substitution.

以取代苯和丁二酸酐为起始原料，经Friedel-Crafts反应，肼合环，Br2/HOAc氧化脱氢后得到一系列1，6-二氢-3-芳基-6-哒嗪酮(2a～2d)。然后将2a～2d与PCl5在POCl3中回流，得到相应的氯代产物3a～3d，将其与酰肼作用，合环后得到一系列未见报道的哒嗪并[3，2-c]1，2，4-三唑类化合物。所有化合物结构均经元素分析，IR，1HNMR和MS谱得以证实，并对其波谱性质进行了讨论

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐