查询词典 asymmetric

Tinnitus, fullness sensational and dizziness were frequent associated symptoms. Their audiograms showed asymmetric and variable hearing loss, and were quite different from noise-induced hearing loss.

在台北市较流行之娱乐场所中，顾客所承受的噪音以流行乐演唱的酒馆为最，其次依序为摇滚乐演唱会、迪斯可舞厅、KTV及小纲珠店。

Our results demonstrate that the symmetric and asymmetric variations above the incident azimuths appear on the radial and transverse components of the receiver function, respectively.

结果表明，当台站下方存在倾向一致的倾斜界面时，远震体波接收函数的径向分量和切向分量分别随震源方位角的变化呈现对称和反对称的规律性变化。

Thus we cooperate to study the function and mechanism of this catalyst in the asymmetric borane reduction reaction, and the following results are obtained.

于是，我们和其合作来深入研究该类配体的不对称催化机制和功能，得到了如下有意义的结果

Asymmetric borane reduction of prochiral ketones is a good process to the synthesis of enantiomerically enriched secondary alcohols.

硼烷对前手性酮的不对称还原是合成手性仲醇的重要方法。

Asymmetric hydroboration is a kind of widely applied and valuable reaction, in which borane reduction of prochiral ketones reaction is an important method.

不对称催化硼氢化反应是应用广泛且具有工业价值的反应，其中的硼烷还原前手性酮反应有着举足轻重的作用。

Part Ⅰ The Research of Chiral Phosphorus Catalysts in the Enantioselective Borane Reduction of Prochiral Ketones ABSTRACT In this paper, the preparation of varied types of chiral phosphorus ligands and their applications as catalysts in the asymmetric borane reduction of prochiral ketones were investigated.

第一部分对映选择的潜手性酮的硼烷还原反应中手性磷催化剂的研究本文研究了多种不同类型的手性磷配体催化剂的合成及其在酮的不对称硼烷还原反应中的应用。

Herein we mainly discuss the design of four series of chialβ-amino alcohols and their application to the asymmetric borane reduction ofprochiral ketones.

本论文主要设计合成了四个系列的手性氨基醇类的催化剂，研究了它们在硼烷对前手性酮的不对称还原反应中的应用。

Then we applied these chrial ligands to asymmetric borane reduction of w-bromoacetophenone and diketones.

将其应用于前手性单酮及二酮的还原中，其中双方酰化脯氨酸在1，6-二苯基-1，6-己二酮的还原反应中可获得最高为90％的ee值。

The first part is concerned with catalytic asymmetric borane reduction of aromatic ketones. Up to 83% ee could be obtained with 10 mol% Al3/BINOL2 complex as catalyst.

在不对称硼烷还原反应方面，利用BINOL作为掌性配位基与Al3组成催化系统还原芳香酮类，反应过程方便快速，最高可获得83%的镜像超越值，我们也推测了可能的反应机构并用以解释所得产物的立体化学组态。

In the reduction of 1, 6-diphenyl-1, 6-hexanedione catalyzed by the bis-squaryl proline, good enantioselectivities were obtained, the ee values were up to 90%.We also studied the asymmetric borane reduction of prochiral ketone catalyzed by a series of thiazolidine ligands.

本文考察了由L-半胱氨酸衍生的2-位无取代基的以及2-位芳基取代的噻唑烷酸及醇配体在前手性酮的不对称还原反应中的催化性能。

Now she was hungry and angry.She began to smoulder.

现在她又饿又气，她开始流露难以抑制的怒火。

You have placed our iniquities before You, Our secret sins in the light of Your presence.

诗90：8 你将我们的罪孽摆在你面前、将我们的隐恶摆在你面光之中。