酸化的

A method for preparing D-valine from L-valine by racemization and chemical resolution is presented.

介绍了L 缬氨酸经消旋化及化学拆分制备D 缬氨酸的方法。

In this research, liposoluble chlorogenic laurate was synthesized by acylation with lauroyl chloride in the presence of triethylamine in non-water phase.

本研究对CGA进行了分子修饰，即在非水相中，以三乙胺为催化剂，对其进行月桂酰氯酰化，制备了脂溶性的绿原酸月桂酸酯。

The problem that noxious chrome of sexavalence and trivalence is present in the galvanizing coat and passivating solution of the prior art is solved substantially by the passivating solution of the present invention.

本发明提供的无铬钝化液可以从根本上解决了现有的产品镀锌层及钝化液中含有有毒有害的六价铬和三价铬元素的问题，并可真正替代现有的含有六价铬和三价铬的铬酸盐钝化液，实现对电镀锌层和热镀锌层的钝化。

Sulfonated poly are prepared by direct polymerization of biphenol A, disodium 4, 4"-difluoro-3, 3"-disulfonate-1, 1-diphenylketone and 2, 6-difluorobezonitrile. The polymers are characterized with ~1H-NMR, FT-IR.

以双酚A，2，6-二氟苯腈和4，4′-二氟-3，3′-二磺酸钠-1，1′-二苯酮采用直接缩合法合成了不同磺化度的磺酸型聚芳醚腈酮，通过FT-IR和~1H-NMR对聚合物进行了表征，证明其结构正确。

Sulfonated poly are prepared by direct polymerization of biphenol A, disodium 4, 4"-difluoro-3, 3"-disulfonate-1, 1-diphenylsulfone and 1, 3-(4-difluorophenyl)benzene. The polymers are characterized with ~1H-NMR, FT-IR.

以双酚A，1，3-二(4-氟苯基)苯和4，4′-二氟-3，3′-二磺酸钠-1，1′-二苯砜采用直接缩合法合成了不同磺化度的磺酸型聚芳醚酮砜，通过FT-IR和~1H-NMR对聚合物进行了表征，证明其结构正确。

The target compound 1 was successfully prepared via esterification, reduction, bromization and cyanation processes by using L--malic acid (2), which is an inexpensive and easily available starting material. The overall yield was 56.7%.

以廉价、易得的L--苹果酸为起始原料，经酯化、还原、溴代和氰化四步反应得到目标化合物-4-氰基-3-羟基丁酸乙酯，合成总收率为56.7%。

Objective To examine the analgesic effect of alginate-chitosan-alginate microencapsulated bovine chromaffin cells transplanted in the peritoneal cavity in mice.

目的 探讨海藻酸钠－壳聚糖－海藻酸钠微囊化牛嗜铬细胞移植到小鼠腹腔后的镇痛效应。

To observe analgesit effects of xenogeneic bovine chromaffin cells and protective effects of the alginate-polylysine-alginate microcapsule.

采用微囊化牛嗜铬细胞异种移植于大鼠和癌痛病人脊髓蛛网膜下方法，观察BCC镇痛作用和海藻酸钠-聚赖氨酸-海藻酸钠微囊对异种移植物的免疫保护作用。

Objective: To use p-toluene sulfonic acid as the catalyst for the esterification reaction of cinnamic acid with isoamyl alcohol in liquid phase.

目的：以对甲苯磺酸为催化剂对肉桂酸与异戊醇的液相酯化反应进行研究。

The trivalent chromium passivation film based on zincate plating obtained has compact structure with no obvious crack, and excellent anticorrosion performance. Different compositions are detected from the surface to inner film, the surface mainly contains Cr2O3-Cr3-ZnO compound, the inner (1030 nm to surface) composes of Cr2O3-ZnO-Zn.The forming process of passivation film possibly consists of four steps which are zinc dissolution, basic area appearance, gelatiniform film forming and converting to passivation film.

结果表明：锌酸盐镀锌层的三价铬钝化膜表面结构致密、无明显裂纹，具有较好的耐腐蚀性能；这种钝化膜表层与里层的组成不同，表层的组成为Cr2O3-Cr3-ZnO共混物；里层(离表层10~30 nm处)的主要组成为Cr2O3-ZnO-Zn共混物；钝化膜的成膜过程可能包括镀锌层的溶解、碱性薄层的形成、胶状膜的形成和胶状膜转化成钝化膜4个步骤。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。