氢化

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。

Finasteride has been facilely synthesized from 4-androstene-3, 17-dione by oxidation, ammoniumation, cyanohydrin, dehydration, Ritter reaction, hydrogenation and dehydrogenation.

本文参考有关文献，以雄烯二酮为起始原料，经氧化开环、内酰胺化、氰醇化、Ritter反应引入叔丁基酰胺、氢化还原、最后氧化脱氢制得非那雄胺。

The resultant was hydrogenised to remove protective group of amino group, then the product was reacted with NaNO2 to give diazonium salt, which was conjugated with salicylic acid, hydroxybenzene, N-salicyloyl glycine acid to get azo derivatives of 4-ASA.

本文首先对4-ASA的氨基和羟基进行了选择性保护，通过氢化还原法选择性脱除氨基的保护基，然后将氢化产物制成重氮盐，通过与水杨酸、苯酚和水杨酰甘氨酸发生反应生成4-ASA的偶氮衍生物，最后在碱性条件下水解得到最终产物。

Reducing agent and to supply a reducing atmosphere; to make hydrogen chloride and hydrogen Bromide; and in

氢气主要用于氨、乙醇、苯胺和甲醇的合成；石油燃料的脱硫；也是一种还原剂和补充减少中的大气；制备氯化氢和溴化氢；还用于有机化合物的氢化。

"It is used to synthesize ammonia, ethanol, aniline, and methanol; to treat petroleum fuels; as a reducing agent and to supply a reducing atmosphere; to make hydrogen chloride and hydrogen Bromide; and in hydrogenation (e.g., of fats)."

氢气主要用于氨、乙醇、苯胺和甲醇的合成；石油燃料的脱硫；也是一种还原剂和补充减少中的大气；制备氯化氢和溴化氢；还用于有机化合物的氢化。

" It is used to synthesize ammonia, ethanol, aniline, and methanol; to treat petroleum fuels; as a reducing agent and to supply a reducing atmosphere; to make hydrogen chloride and hydrogen bromide; and in hydrogenation (e.g., of fat s)."

氢气主要用于氨、乙醇、苯胺和甲醇的合成；石油燃料的脱硫；也是一种还原剂和补充减少中的大气；制备氯化氢和溴化氢；还用于有机化合物的氢化。

The recent growing up of chemistry of hydrogenases, especially the Fe-only hydrogenase have renewed interest in classical organometallic diiron dithiolate complexes.

近几年发展起来的氢化酶化学，尤其是唯铁氢化酶活性中心的化学模拟研究，把铁硫簇化学的研究推向了又一高潮。

The effects of temperature and catalyst concentration on hydrogenation activit...

同时讨论了该氢化体系的温度和催化剂的浓度对氢化活性和选择性的影响。

No indene was found, clearly showing that indanes and indenes may originate from different precursors, and algae lived in saltwater are important contributors to the indanes.

没检测到茚类化合物，说明二氢化茚和茚可以源自不同的先质，生活于咸水环境的低等生物是二氢化茚类化合物的母质之一。

Hydrocortisone is widely used in patients with septic shock even though a survival benefit has been reported only in patients who remained hypotensive after fluid and vasopressor resuscitation and whose plasma cortisol levels did not rise appropriately after the administration of corticotropin.

1月10日《新英格兰医学杂志》报道，Hadassah希伯来大学医学中心等地的研究人员证实，无论是对所有的脓毒性休克患者还是只针对那些对促肾上腺皮质激素无反应的患者，氢化可的松都不能改善生存率或逆转休克症状；但是，对于已经逆转了休克进程的患者来说，氢化可的松可以加快休克的恢复。

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。