查询词典 chiral

Chiral SalanCrX complexesa saturated version of SalenCr(ⅢX are designed,and in conjunction with an ionic quaternary ammonium salt or organic strong base can efficiently catalyze the asymmetric,regio-and stereoselective alternating copolymerization of CO_2 with rac-PO at mild conditions to afford isotactic-enriched polycarbonates with～95%head-to-tail linkages and moderate enantioselectivity.

本论文在Salen构型配体的基础上，设计合成了一系列手性Salan型铬配合物，并将其与季铵盐/有机强碱组成亲电-亲核双组分催化体系，在室温下可以有效的催化CO_2和环氧丙烷的不对称交替共聚反应，实现了CO_2和环氧丙烷的不对称交替共聚反应的区域和立体化学控制，得到95%的头尾连接单元和中等光学纯度(对映体过量值ee%≈70%)的全同结构的聚碳酸酯。

A novel chiral block copolymer PCys-b-PPO-b-PCys bearing Leucine in the side chain was synthesized for the first time.

首次合成了侧链带有手性基团的聚半胱氨酸－b-聚环氧丙烷－b-聚半胱氨酸嵌段共聚物。

Novel chiral block copolymer PCys-b-PPO-b-PCys bearing Leucine in the side chain was synthesized for the first time.

bstract 首次合成了侧链带有手性基团的聚半胱氨酸－b-聚环氧丙烷－b-聚半胱氨酸嵌段共聚物。

To obtained useful chiral multi-substituted alkene-nitrile intermediates, the abnormal Beckmann rearrangement and their applications to the synthesis of the natural products were studied.

用甾体-17-酮肟的非正常Beckmann重排反应生成的相应的烯-腈化合物是合成18-去甲基甾体的重要中间体。

QN 〓PHAL,〓PHAL and 〓PHAL were quaternized by refluxing with benzyl bromide to give ligands 8, 9 and 10 respectively. 2. The chiral ligands were applied to the AD reaction of olefins with NMO as co-oxidant and PEG (400 MW) or PF〓 as reaction media.

以奎宁和奎尼定为原料分别与1，4-二氯-2，3-二氮杂萘反应制备〓PHAL和〓PHAL，然后通过〓PHAL、〓PHAL及〓PHAL与苄基溴的季铵化反应制备单季铵盐手性配体8、9和10。

In addition, the effects of the pH value of the buffer system, the concentration of the CD and the voltage on the chiral separation were investigated.

在以CM-β-CD为手性拆分试剂的基础上，还考察了各种因素诸如流动相的pH值、环糊精的浓度以及电压对分离的影响。

Methods:The factors including cyclodextrin,pH value,buffer concentration,voltage,and temperature,that influence separation of chiral isopmer were optimized.

通过探讨环糊精的种类、浓度，缓冲液的pH值、浓度、电压以及温度对分离的影响，选择手性分离的最佳条件。

This dissertation focused on the development of new chiral capillary electrophoresis approaches for the analysis of amino acids and their analogs, resulting in some important progress as is shown below

本论文针对当前手性毛细管电泳中的一些重要问题进行研究，发展了一些新的高效手性选择体系和方法，适用于氨基酸及其类似物等的拆分，具体如下

Methods:Chiral capillary gas chromatographic analysis method with large volume injections was used to separate the stereoisomers of soman.

建立灵敏、特异的梭曼 4个光学异构体的分析方法对研究梭曼中毒后体内代谢过程、解毒药物的药理学评价及中毒诊断都具有重要意义。

This requirement may be satisfied by the submission of information such as the following: name (generic name, chemical name, code number); Chemical Abstracts Service number if available; description (e.g., appearance, color, physical state); molecular formula and molecular weight; structural formula (including ionic state if applicable); stereochemistry identifying chiral centers, cis-trans isomerism, etc.

该要求可以通过提供下述信息来满足：名称（通用名、化学名、编码等）、化学摘要服务编码、性状描述（如：外观、颜色、物理状态）、分子式和分子重量、结构式、立体化学（找出手性中心、顺式反式异性等）、对映结构体比率（如：外消旋物、规定的异构体、对映异构物和固态形式的混合物）、溶解度概况、分配系数、溶液 pH 值、解离常数、熔点或沸点、折射率、比重。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。