查询词典 cleavage

From the ester n, the intermediate Ⅲwas produced by the Sonogashira coupling reaction with terminal alkynes under the co-catalysts of Pd2 and Cul. These final products of alkynyl benzamide derivatives IV were obtained by the cleavage of support with primary or second amines.

液相合成兼容了固相合成可快速简便地对产物进行分离纯化以及溶液相合成可在均相条件下进行反应和用常规手段对反应中间体进行分析检测的优点，用聚乙二醇4000作为可溶性聚合物支持体，通过醚键将[1，3，5]氯三嗪连接在PEG上制备成PEG支持的新型的可溶性聚合物试剂I。

The invention comprises a cyclopalladated catalyst with axial chiral binaphthyl backbone containing phosphine ligand as well as the synthesis thereof, and the application of the catalyst with cyclopalladated catalyst with axial chiral binaphthyl backbone containing phosphine ligand with a similar structure to the hetero atom norbornadiene ring cleavage reaction through an asymmetric catalytic organic boron agent.

本发明包括一类具有轴手性联萘骨架含膦配体的环钯催化剂及其合成，以及其与具有类似结构的轴手性联萘骨架含膦配体的环钯催化剂在不对称催化有机硼试剂对杂原子降冰片二烯开环的应用。

Avian influenza virus was isolated from the caecal tonsil, faeces, and kidney of the domestic ducks. The isolated virus was identified as a highly pathogenic H5N1, with a haemagglutinin proteolytic cleavage site deduced amino acid sequence of ... QREKRKKR/GLFGAIAG ... In order to determine the pathogenicity of the isolate, eight 6-week-old specific pathogen free chickens were inoculated intravenously with the virus, and all birds died within 24 h after inoculation.

病毒抗原可以从鸭的盲肠，扁桃体，肾脏及粪便分离出来，并且确定这种病毒是高致病性的H5N1，还从血凝素蛋白分解位点推断出病毒的氨基酸序列，为了了解独立群的发病机理，对8只6周龄鸡静脉注射这种病毒，结果所有的均在注射后24小时死亡。

The results show that the formation of dry gas is abided by reaction mechanism involving the cleavage of pentacoordinated Carbonium ion which is formed by the protonation of alkanes over acidic catalyst.

结果表明，烷烃分子首先在催化剂酸性中心作用下发生质子化反应，烷烃分子链上易受到氢质子进攻的位置一般在其叔碳原子或碳链中心碳原子附近的C—H键或C—C键处，形成两种反应过渡态物种——五配位正碳离子H-Carbonium和C-Carbonium。

How such intramolecular cleavage can occur when the amino and carboxy termini of the mature protease are part of an intersubunit -sheet located distal from the active site is unclear.

它所起作用是将新形成的聚合蛋白质Gag 和 Gag-Pol分开，以产生结构和功能蛋白的成品，包括其本身在内。

Two pathways of cleavage and conversion in ring B of ergostane and cholestane are summarized.

第二部分总结了麦角甾烷及胆甾烷B环裂解和转化的两种途径。

The cleavage facets on the fracture surface of three-point bending specimens at RT were determined crystallographically in an Electron Probe with the EBSD.

利用电子背散射衍射对合金室温弯曲断口中解理刻面的晶体学取向进行了测定。

The proposition of reaction pathway suggested that the initial degradation of pyridaben proceed via C-S bond cleavage between phenyl ring and heterocyclic group, and then promote a serious of reactions such as substitution, oxidation and dealkylation.

反应路线推导表明降解哒螨酮首先是在苯环与杂环之间C-S键处断裂为两个部分，接着发生取代、氧化，去烷基等系列反应。

The cage effect of Gn potassium aqueous solution calculated by theα-cleavage photoreaction product distribution of substituted dibenzyl ketone was 14%, 18%, 22% and 42% for generations 1-4, respectively, which indicates that G4 takes a more close spherical shape with strong confine ability.

研究结果表明，羧基为末端基团的芳醚树枝形聚合物Gn (n = 1-4)钾盐水溶液笼效应随代数增加而增大，从G1到G4，笼效应分别为14%、18%、22%和42%，树枝形聚合物3代到4代从开放结构变为近乎球形的封闭结构的显著变化使G4表现出明显高于其他三代的笼效应。

In chapter four, the preperation of ytterbium diiodide was examined. The reductive cleavage of Se-Se bond and S-S bond induced by ytterbium diiodide was investigated. The reaction of diselenides and disulfides with allylic bromide promoted by ytterbium diiodide was also examined. The intermolecular Barbier-type reaction induced by ytterbium diiodide was studied. In the last section of this chapter, the intermolecular reductive coupling of nitriles with azides induced by samarium diiodide was investigated.

第四章，研究了二碘化镱的制备方法，以及二碘化镱作为一种优良的单电子转移试剂在有机合成中的应用：二硒醚的Se--Se键和二硫醚S-S键的还原断裂，及其在合成烯丙基硒醚，硒代酯和烯丙基硫醚，硫代酯中的应用，实验结果表明二碘化镱也能促进分子间的Barbier反应，而文献认为二碘化镱不能促进分子间的Barbier反应；最后研究了二碘化钐促进的叠氮化合物与腈的交叉还原偶联反应，一步高收率地制备脒的方法。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。