查询词典 olefinic

Because the olefinic hydroxyl groups are linked with olefinic carbon, so it can ionize H〓 ion and present the properties of weak acid, and so the olefinic hydroxyl groups change into the structure of alcoholate in the presence of alkali , but the structure of alcoholate may change into the structure of olefine alcohol again, after the Na〓 ions is removed, or when the pH value of its solution turn into pH. Because the structure of the olefine alcohol is not stable and is easy to isomerizate to become the structure of olefine ketone, so there appear the ca. 1730cm〓 C=O absorption peak in the IR spectra of the products.

明确指出了在C〓、C〓富勒醇中存在烯碳羟基与叔碳羟基等二类羟基，烯碳羟基由于与一个共轭体系相连，从而其羟基可以离解而呈现出弱酸的性质，因而在碱性条件下易形成烯醇钠盐的结构，当除去钠离子后或在酸性溶液中，烯醇钠盐结构转变为烯醇结构，但由于烯醇结构不如烯酮结构稳定，从而形成烯醇结构后，烯醇结构异构化为烯酮结构，因此在其产物的IR谱图上出现1730cm〓附近的C=0吸收信号。

Novel sulfonic acid and carbon chains of mixed-mode packing materials were synthesized through sulfonating polymer-encapsulated zirconia covered by a porous copolymer of olefinic hydrocarbon and divinylbenzene on its surface.

通过共聚交联方法将长链碳烯-苯乙烯包覆到锆胶表面上，得到聚合物包覆固定相，再对该填料进行磺化引入离子官能团到聚合物表面，得到混合型固定相。

The copolymerization compound comprises based on a proportioning ratio by weight: 25-99 percent ethylene aromatic series monomer; 0-30 percent olefinic undersaturation nitrile monomer; 1-50 percent olefinic dibasic acid ramification monomer.

这种共聚组合物按重量百分比包含：25至99％的乙烯基芳香族单体；0至30％的烯属不饱和腈类单体；1至50％的烯属二元酸衍生物单体。

Difunctional group reagents, which have metal and heteroatom linked to the olefinic carbon atoms, play an important role in organic synthesis, especially in developing many convenient methods for the stereoselective synthesis of substituted alkenes.

含金属或杂原子的双官能团试剂为取代烯烃的立体选择合成提供了许多方便方法，在有机合成中具有重要作用。

Amino-2-methylpropanol was utilized as a chemical modifying reagent to modify carboxyl groups in unsaturated fatty acids into nitrogen-containing heterocycles, which effectively suppressed the migration of double bonds of the alkenyl within the electron impact source and led to regular informative mass spectra indicative of the position of the olefinic bonds in the chain.

以2-氨基－2-甲基丙醇为脂肪酸的化学修饰试剂，将不饱和脂肪酸羧基化学修饰试剂，将不饱合脂肪酸羧基化学修饰成含氮杂环，从而避免了链烯基中碳碳双键在EI源中的移动，并使质谱呈现显示双键位置的规范信息。

In this project, we have developed and established a new methodology of polymerization, which can serve as a general "pdatform" for manufacturing polymer nanospherical particals with superhigh performance from most olefinic and diolefinic monomers.

本项目发展了一种新的高分子纳米球粒制备技术，研制了超高效纳米球粒制备平台，制备高分子球粒种类包括：单烯和双烯类化合物为单体的系列高分子纳米球粒材料。

for preparing n-boc or n-cbz derivatives of chiral alpha,alpha'-disubstituted pyrrolidines containing olefinic bond and acetylene bond

一种制备含烯键和炔键取代基的手性α，α'-二取代吡咯烷的n-boc或n-cbz衍生物的方法

They are sometimes difficult to differentiate from aromatic or olefinic absorptions.

有时它们就难于和芳香族或烯烃的吸收峰相互区别。

For thermally curable etch-resist inks comprising an activated olefinic group the activated olefinic monomer preferably contains a metal chelating group.

对于热固化刻蚀抵制油墨组成一组激活烯烯单体的活性最好包含一个金属螯合组。

The first step in the degradation is most probably the classical ester scission reaction to give a carboxylic acid and olefinic end groups. Further ester scission on the adjacent ester groups of carboxylic acid and olefinic molecular chains can then lead to the formation of lower weight pyrolytic products, such as: CH〓=CHOCOPhCOOCH=CH〓、CH〓=CHOCOPhCOOH and HOOCPhCOOH, and they can pyrolyze continually to produce substrate pyrolytic compounds, such as: HOOCPhCOCH〓、PhCOOH、PhH、PhCOCH〓 and CO、CO〓. At the same time, a corsslinking cyclization reaction occurred of the formation of the gas products during the degradation of PET.

断裂大分子链端邻近羰基和乙烯基的酯键持续断裂，不断地形成小分子裂解产物，如：CH〓=CHOCOPhCOOCH=CH〓、CH〓=CHOCOPhCOOH以及HOOCPhCOOH，这些产物还会进一步裂解成分子量更低的小分子裂解产物，如：HOOCPhCOCH〓、PhCOOH、PhH、PhCOCH〓以及CO、CO〓等，与此同时，一部分乙烯基酯端基的大分子链碎片会发生支化而相互连接，再经&链脱离&和环化反应形成难燃的交联产物。

Chrysanthemum of 10 thousand birthday is lax to edaphic requirement, with the arenaceous qualitative loam with fecund, good drainage had better.

万寿菊对土壤要求不严，以肥沃。排水良好的砂质壤土为好。

He unstepped the mast and furled the sail and tied it.

他拔下桅杆，把帆卷起，系住。