羟基

Two special structural features of the sulfonium salt were proved to stabilize its corresponding ylide and depress the 2,3-sigma rearrangement. One is that there is a trimethylsilyl in the end of the allylic double band. This silicon atom can stabilize a α-carbon anion and the corresponding ylide. Another is that there is hydroxy group in the beta-position of sulfonium atom. The oxygen of this hydroxy group may stabilize the sulfonium cation.

为了稳定生成的烯丙基硫叶立德，并抑制它的2， 3-sigma 重排反应，在硫叶立德结构上做了两方面的考虑：一是在烯丙基双键的未端引入硅基，利用硅原子对 a -碳负离子的稳定作用来稳定烯丙基硫叶立德；二是在硫原子的 b -位引入羟基，利用羟基氧对硫正离子的作用来稳定硫叶立德。

In this organogel structure, the p–p stacking interactions among the HPB moieties, the hydrogen-bonding interactions between the urea moieties, and the van der Waals forces between the long alkyl chains cooperatively stabilized the aggregate structure; these are well-known interactions in gel systems.2a,5 Specifically to clarify the effect of the hydroxyl group in the HPB unit on gelation, we also designed and synthesized reference compound 2, which does not contain an adjacent hydroxyl group and thereby cannot induce its planar keto tautomer upon excitation.

在这个organogel结构、p-p叠加之间的相互作用在HPB根、实验之间的相互作用尿素根之间，范德华力长链烷基之间的合作稳定了合计结构；这些都是著名的交互作用的凝胶 systems.2a明确厘清，羟基的效果集团在HPB装置设计和凝胶，我们也是合成的化合物、参考不包含了邻近的羟基从而无法归纳其平面在keto tautomer激励。

The present invention discloses a method for separating and extracting polyhydroxy fatty acid ester from bacterial thallus.

本发明公开了一种从细菌菌体内分离提取聚羟基脂肪酸酯的方法，以便能够有效地从细菌菌体内分离提取聚羟基脂肪酸酯。

By the mechanism of the electrocyclic reaction, three groups of 4-hydroxy-2-cyclobutenones 4 were designed and synthesized to investigate their behaviors underthe thermolysis conditions Meanwhile, a new procedure for preparation of 2(5H)-furanone 5 Was discovered.

根据电环化反应机理，我们设计了三组不同类型的4-羟基-2-环丁烯酮(4)。通过对4-羟基-2-环丁烯酮(4)进行热解，发现了一种制备2(5H)-呋喃酮类化合物(5)的新方法。

BACKGROUND: Copolymers of 3-hydro-xybutyrate and 3-hydroxyvalerate is a synthesized product of microorganism in unbalance growth environment, characterizing by degradation and thermoplasticity.

背景：聚羟基丁酸-羟基异戊酯是微生物在生长条件不平衡状态时合成的产物，具有可降解性、热塑性，作为组织工程的新型支架材料，越来越受到重视。

The modified surface with a high friction coefficient becomes hydrophilic.The main reason is that: there is a basic photoreaction of oxygen under UV radiation,in which atomic oxygen may highly be generated.Then the oxygen atom reacts with trace amounts of water to form hydroxyl.

其机理为：在紫外照射条件下氧气发生光化学反应形成氧原子，氧原子和微量的水发生反应形成羟基，羟基和烃发生夺氢反应形成硅烷的烃自由基，同时硅烷的烃自由基会发生β-scission裂解形成较短链的自由基。

Blends of P(3-hydroxylbutyrate-co-4-hydroxylbutyrate) [P(3HB-co-4HB)] plasticized by triethyl citrate, soybean oil and glycerin triacetate have been prepared by a solvent casting film method. The effects of varying the type and content of plasticizer on the properties of the polymer blends have been studied.

采用溶剂成膜法制备了柠檬酸三乙酯、大豆油和甘油三乙酸酯增塑的聚（3-羟基丁酸酯－co-4-羟基丁酸酯）共混物，考察了增塑剂的种类及其用量对共混物热学和力学性能的影响。

The result indicates thato-PD is converted to one trimer with ca.

羟基自由基抑制剂和氧合血红素物种抑制剂尿酸都不抑制该氧化反应，这些结果表明邻苯二胺的羟基化反应没有包括在其氧化过程中。

Compound 9 is glycosylated in the presence of TMSOTf with rhamose-derived trichloroacetimidates to provide target trisaccharide Saponin 1, oleanolic acid 3-yl-2,4-di-O-a-L-rhamnopyranosyl -p-D-glucopyranosideCoumpond 18 is prepared with oleanic acid and Bromide 11 through phase-thansfer catalysis glycosylation manner.

三糖皂苷Saponin 1是以葡萄糖齐墩果酸皂苷为起始原料，用BBTZ(1-苯甲酰苯并噻唑)选择性保护葡萄糖3′，6′-羟基得到化合物9，然后以化合物9为糖基受体，进行一步糖苷化可以在化合物9的2′，4′-羟基上同时引入两分子鼠李糖，最后脱掉所有的保护基得到目标化合物Saponin1。

The reparing high molecular material was divided into absorbable and unabsorbable material,the former included polyglycolic-acid and polyglaction,the later consists of polypropylene polyester and expanded polytetrafluoroethylene.

人工高分子修补材料主要有可吸收和不可吸收两大类，前者有聚羟基乙酸和聚乳酸羟基乙酸两种，后者有聚丙烯网、膨体聚四氟乙烯片及聚酯纤维网。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。