对映的

The appearance of-enantiomer after incubation with single-enantiomer revealed the enantiomeric inversion of-isomer to its antipode. While no obvious stereoselective degradation or enantiomeric inversion were observed in other test soils.

左右旋对映体在3~#土壤中的降解速率有明显差异，二者半衰期相差0.95周；添加外消旋体培养6周后ER值达到1.65，表明左旋体被优先降解；同时在该土壤中存在左旋体向右旋体的转化现象；在其他几个土壤中均未有明显的选择性降解或对映体转化现象。

The concentration of D-phenylalanine in the external phase and the separation factorαcan be expressed as: The diffusion of boundary layer in outer aqueous phase is the controlled process while the concentration of D-phenylalanine in the external phase far less than the concentration of chiral carrier in the emulsion liquid membrane phase, then the diffusion coefficient k_e of boundary layer in outer aqueous phase can be achieved by data fitting.

外水相苯丙氨酸对映体的浓度以及分离因子α表示为：当外相对映体浓度远小于液膜相手性载体浓度时，该手性传质过程中外相边界层的扩散为控制步骤，利用数据拟合得到了外水相与液膜相界面边界层扩散的传质系数k_e。

The enantioselective reduction of aromatic ketones was investigated by using celeriac chips as biocatalysts under mild and environmentally benign conditions, which afforded corresponding optically active-1-aryl alcohols. The enantioselectivity of products was in accordance with the Prelog's rule.

研究了用芹菜茎薄片在温和与环境友好的条件下催化芳香酮的对映选择性还原反应，制备得到具有光学活性的-1-芳基醇，产物的对映选择性符合Prelog规则。

Herein, we report the enantioselective total syntheses of slagenins A-C and their antipodes. Starting from readily available ethyl -4-chloro-3-hydroxy-butanonate, elongation of the carbon chain with diazomethane, followed by oxidation of the given α-diazoketone using distilled DMD, afforded a key intermediate α-ketoaldehyde .

本文从方便易得的-4-氯-3-羟基-丁酸乙酯出发，经重氮甲烷延伸碳连、DMD氧化相应的α-重氮酮，制得α-酮醛；该化合物与尿素在氢氟酸作用下，以协同方式非对映选择性的直接构建了cis-四氢呋喃并[2，3-d]咪唑啉-2-酮双环结构，进而合成了天然产物slagenins A、B、和C的对映体。

In section 5, separation of di-peptides with two chiral centers using cyclodextrin modified micellar electrokinetic chromatography was investigated.

论文的第五章采用环糊精修饰的胶束电动色谱手性拆分了具有两个手性中心的二肽对映体，并应用于模拟人血清样品中这些二肽对映体的分析。

However, the formation of metal chelation at one or two side of biphenyl resulted a pair of enantiomers of monometallic or bimetallic complexes. Moreover, if the coordinating groups have chiral element (e.g., chiral oxazolines), the diastereomeric metal complexes will be formed.

而且，如果配位基团上带有手性元素，它们跟金属配位后得到一对非对映异构体，由于手性元素的影响，形成这一对非对映异构体的能量是有差异的。

In the case of racemate 2, better resolution was obtained when using 2-propanol as modifier in the place of methanol and ethanol, while for racemate 1, methanol provided the best performance. Both retention and resolution decreased with increase in pressure.

结果表明对映体的保留因子均随着改性剂含量的增加而显著下降，当改性剂含量大于10%时，保留因子的下降趋势变缓；分离帕罗酮酯时，异丙醇作改性剂的分离度和分离因子均最大，分离帕罗醇对映体时，甲醇是最佳的改性剂。

Some compounds possessing chiral center themselves may be racemates and appear racemic phenomenon in the extraction and separation from medicine herbs, structure modification and chemical synthesis.

但是，由于含有手性中心的中药有效成分本身可能是消旋体、或者在分离提取、结构改造及化学合成时会出现外消旋化现象，使新药研制与开发中面临对映体成分的分离制备、体内手性药物分析及对映体特异性药代动力学研究等重大难题。

Enantiomer or solid-state form ratios (e.g., for racemates, and for defined admixtures of isomers or enantiomers or solid-state forms); solubility profile (aqueous and nonaqueous as applicable); partition coefficients; solution pH; dissociation constant; melting or boiling point; refractive index; specific gravity.

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。

Enantiomer or solid-state form ratios (e.g., for racemates, and for defined admixtures of isomers or enantiomers or solid-state forms); solubility profile (aqueous and nonaqueous as applicable); partition coefficients; solution pH; dissociation constant; melting or boiling point; refractie index; specific graity.

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。

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐