查询词典 amination

We studied effects of additives in the allylic amination reaction. We found that4NF could improve the reactivity and enantioselectivity.

对于烯丙基胺化反应，我们研究了外加添加剂对对映选择性的影响，我们发现四丁基氟化铵的加入可以大大提高反应速度及对映选择性。

When ligands with only planar chirality were used in the two model reactions (allylic alkylation and amination), comparatively high enantioselectivities were obtained.

令人鼓舞的是设计合成的只具有平面手性的膦氮配体，也可以取得中等到良好的对映选择性。

Starting form chitosan,amidogen protecting,cross linking,etheration,amination,amidogen release and addition reaction with CS_2,and chitosan derivative containing dithiocarbamate group was firstly prepared.

本文在课题组前期关于淀粉改性重金属捕集剂研究工作的基础上，参考国内外的相关文献，建立了以壳聚糖为主要原料制备二硫代氨基甲酸改性壳聚糖重金属捕集剂的合成工艺。

The effects of rare earth elements on Reformation of amination -catalyst for fatty alcohol were analyzed in this paper.

研究表明，稀土元素具有和镍相反的对高沸物成分的抑制作用，稀土元素的加入普遍提高了脂肪醇胺化反应的选择性。

The key technology of the catalytic amination process of fatty alcohols is the amination catalysts with high selectivity.

催化剂的关键性能是其选择性。

The selective amination of ethylene oxide to ethanolamine has become a hot spot in amination reactions in recent years.

环氧乙烷选择性胺化制乙醇胺成为近年来胺化反应的热点课题。

This paper reviews the recent progress of all kinds of reductive amination methods and their ap-plications in organic synthesis, particularly emphasis on the introduction to the reductive amination with high efficiency and high selectivity.

综述了近几年来各种还原胺化方法的研究进展及其在合成中的应用，尤其对高效和高选择性的还原胺化进行了重点介绍

The intermolecular catalytic amination of alcohols is examined by using the catalytic amination of ethanol with piperazine to N-ethylpiperazine as a model.

以乙醇和哌嗪催化胺化合成N-乙基哌嗪的反应为模型，对分子间醇的催化胺化反应进行了研究。

The develop-ment of ligands expands the scope of substrates, improves reaction selectivity and realizes the amination of the cheaper and available aryl chlorides. The application of weak base improves the compatibility of functional groups. Pd-catalyzed amination of aryl halides are used in the synthesis of arylamine.

配体的发展扩展了底物的适用范围，提高了反应的选择性，实现了廉价易得的氯代芳烃的胺化，弱碱的使用提高了官能团的兼容性，因此Pd催化芳胺化广泛应用于合成芳胺类化合物。

Result of thermogravity analysis showed that the thermal stability of polyvinylamine chloride lowers with increasing in amination degree. Moreover, properties of dilute aqueous solutions of three types of poly chloride with different amination degree were compared by use of viscosimetric, conductometric, and potentiometric measurements. Results showed that both the electrostatic interaction of neighboring groups on the chain and the reduced viscosity of poly chloride are increased with increasing the degree of amination of poly . The equivalent conductivity is decreased with the increasing the concentration of poly chloride and increased with the increasing the amination degree of poly .

研究了聚乙烯胺盐酸盐的热稳定性和水溶液性质，发现：随着胺化度的提高，聚乙烯胺盐酸盐的对热稳定性逐步降低；聚乙烯胺盐酸盐是一种典型的聚电解质，其水溶液的pH值随平均分子量的变化并不明显，而随着聚乙烯胺胺化度的升高，pH值降低；随着聚乙烯胺盐酸盐的平均聚合度由82.3增加到201.8，它的m值（用于表征聚电解质侧链基团之间相互作用大小的常数）从5.13升高到5.58，而当聚乙烯胺盐酸盐的平均聚合度增加到311.4时，它的m值反而降低到了5.48；随着胺化度由55.65%升高到82.36%，m值由3.65提高到5.50；随着聚乙烯胺盐酸盐的平均聚合度的提高，聚乙烯胺盐酸盐的平均解离常数由7.48降低到7.26，同时随着胺化度的提高，聚乙烯胺盐酸盐的平均解离常数也由8.33降低到7.37；随着聚乙烯胺盐酸盐浓度的提高，溶液的摩尔电导率逐步降低，随着聚乙烯胺胺化度和聚合度的提高，溶液的摩尔电导率有所升高；在pH值为4左右时，聚乙烯胺盐酸盐的比浓粘度分别达到极值，而与聚合度的大小关系不大；聚乙烯胺盐酸盐的特性粘数明显高于其原料聚丙烯酰胺的特性粘数，分子量对特性粘数的影响十分明显，胺化度对特性粘数的影响并不显著。

I am sure after a few weeks of adaptation and familiarization I will have no difficulty in functioning on a daily basis in an English speaking society or in participating fully in graduate studies.

在大学的三年的学习生活不仅给予我自身的充实，更重要的是磨练和培养了我较强的自觉能力和严谨，踏实的作风以及不怕困难的精神，对未来充满了信心！

As the first volcanoes erupted, one of the gases that bellowed out was steam.

在第一批火山喷发时，喷出的气体之一就是水蒸汽。