氧化合物

Anti-knock additive tetraethyl lead,vapor pressure,cetane number and content of aromatic hydrocarbon,ethylenes,sulfur and oxides respectively in the motor fuel are more detailedly analysed in regard to their effect on motor vehicle exhaust emission.

较为详细地分析了燃油中四乙铅抗爆剂、芳烃含量、烯烃含量、硫含量、蒸气压、十六烷值及含氧化合物等对汽车排放的影响，并简述了其发展趋势。

Seven major methods and their reaction characteristics for the synthesis of primary vicinal diamines starting from epoxides, and alkenes etc.

详细综述了从环氧化合物、烯烃等为起始原料合成一系列一级邻二胺的七条主要路线，并比较了各条反应路线的特点。

Started from D-tyrosine, we obtained the tetramic acid 96 using Jouin reaction. The assembly of the second fragment 109 was stared from 1,4-butandiol,using asymmetric alkylation reaction developed by Oppolzer as a key step. Coupling of the tetramic acid 96 with 109 provided the key intermediate 110 according to Yoshii\'s procedure. After remove protective group and Sharpless epoxidation, we obtained the key intermediate 113. Its macrocyclization to form the final product is in progress.

本论文的第二章主要对Macrocidin A开展了合成工作，我们从D构型的酪氨酸出发，经过官能团转换；利用Jouin反应生成Tetramic acid 96，另外一个片断从1，4-丁二醇开始经过多步反应生成碘化物104，利用Oppolzer发展的手性樟脑磺酰胺为辅基参与的不对称烷基化反应，引入手性甲基，生成关键中间体109，接着通过Yoshii发展的方法连接96和109生成110，经过Sharpless不对称环氧化反应建立环氧化合物，然后脱去保护基得到关环前体113，分子内的Mitsunobu反应进行关大环反应正在进行之中。

A method to synthsis a - methylene - r - butyrolactones was reported by the substituted (a - carbethoxyvinyl) cuprate intermediates, generated by the addition of higer order cuprate to acetylenic ester,traping with epoxides stereoselectively.

本文报道了通过以高序铜代替低序铜对炔酸酯加成得到的取代铜与端基或环状环氧化合物的立体选择性反应，较高产率的合成α，β-取代烯酯，进而可合成α-亚烷基-γ-丁内酯类衍生物。

Withbimetallic μ-oxo alkoxide as initiator, the homopolymerization of MG follows atypical living process.

以双金属烷氧化合物为引发剂，MG单体的聚合遵循经典的活性聚合过程。

The monomer reactivity ratios of lactides weredetermined with 〓 as catalyst or bimetallic μ-oxo alkoxide as initiator.

在辛酸亚锡和双金属烷氧化合物引发体系中，分别测定了交酯类单体的竞聚率。

Leigong Vine is particularly efficacious in its anti-inflammatory and immune functions. Three diterpene epoxides isolated from the root of Leigong Vine exert a a decided effect in fighting leukemia.

雷公藤有显著的抗炎和免疫作用，根部分离出的三种二萜环氧化合物，有明显的抗白血病作用。

One test is circulating test which tailing water is filtered and reused,another test is adding a little frother in water before adding coal sample.

结果表明，循环水中积聚的有机物主要是醇、酮、羧酸盐等含氧化合物；有机物积聚可提高精煤回收率，改变浮选的选择性

There are very few reports in the literature for the ring opening of epoxides with heterocyclic amines.20 These methods require high temperature and pressure.

有极少数的报告，在文献上为开环环氧化合物与杂环amines.20这些方法需要高温度和压力。

The transfer of R group from XZnR occurrs from the same face as the oxygen of epoxide and results in a syn addition since organozinc reagents XZnR could act as a Lewis acid system as well as being nucleophilic in character.

我们制备一类新型有机锌试剂，研究它们在适宜的反应条件下，直接对环氧化合物进行开环反应，得到顺式开环产物，实现了有机金属试剂的立体选择性顺式开环。

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！