乙二醇

In order to examine possible relations between freezing properties andthe number of hydroxyl groups in solute molecules, a differential scanning calorimeter (Pyris-Diamond DSC) was employed to study the thermal behaviors of polyalcohols aqueous, such as hydration properties, glass transition, and devitrification.

利用差示扫描量热仪，研究了乙二醇、丙三醇、1，3丙二醇、1，3丁二醇和2，3丁二醇水溶液的水合性质、玻璃化转变温度和反玻璃化转变温度，得出了这些性质与溶液浓度的关系。

Under the catalyst, the polymerization retarder, the including water medicinal preparation existence condition, the methylacrylic acid and the polyethylene glycol single methyl ether (400) direct esterification synthesis methylacrylic acid polyethylene glycol single methyl ether (400) ester, and the influence factors of the catalyst, polymerization retarder, including water medicinal preparation has mellowly carried on the comparison.

摘要在催化剂、阻聚剂、带水剂存在的条件下，由甲基丙烯酸与聚乙二醇单甲醚(400)直接酯化合成甲基丙烯酸聚乙二醇单甲醚(400)酯，并对酸醇比、催化剂、阻聚剂、带水剂等影响因素进行了比较。

The phase separation behavior of different nonsolvent additives (methyl ethyl ketone, glycol methyl ether and diethylene glycol) on PPESK casting solution was studied at 20℃according the linerized cloud point correlation.

结合线性浊点关系，根据浊点滴定试验，通过三元相图研究了20℃下非溶剂添加剂(丁酮，乙二醇甲醚，一缩二乙二醇)对PPESK铸膜液体系的相分离行为。

The preparation of esterified derivant : it is prepared by the esterifying reacting of above (3) product and 4g dodecylbenzene sulphonic acid heated in water bath at 40℃ within 30min.

聚环氧氯丙烷乙二醇哌啶接支酯化衍生物的制备：4g十二烷基苯磺酸于40℃水浴条件下聚环氧氯丙烷乙二醇哌啶接支衍生物进行酯化反应。

H3PW6Mo6O40/TiO2 was used as the catalyst in the synthesis of cyclohexanone ethylene ketal. The effects of varying the n:n ratio, catalyst dosage and reaction time on the yield were investigated.

以H3PW6Mo6O40/TiO2为催化剂，对以环己酮与乙二醇为原料合成环己酮乙二醇缩酮的反应条件进行了研究，较系统地研究了酮醇物质的量比、催化剂用量、反应时间对收率的影响。

Cyclohexanone ethylene ketal was synthesized from cyclohexanone and glycol in the presence of H3PW12O40/MCM-48. The factors influencing the synthesis of molar ratio of glycol to cyclohexanone, the quantity of catalyst and the reaction time were discussed and the best conditions were found out.

报道了以分子筛MCM-48负载磷钨酸(H3PW12O40/MCM-48)为催化剂，通过环己酮和乙二醇反应合成了环己嗣乙二醇缩酮，探讨了H3PW12O40/MCM-48对缩峒反应的催化活性，较系统地研究了酗醇物质的量比，催化剂用量，反应时间诸因素对产品收率的影响。

Inside benzene or toluene solvent, in the presence of stannous octoate as catalyst and under the conditions of no water, no oxygen, heating and stirring, MPEG and aliphatic cyclic monomer are ring-opening polymerized to obtain binary block MPEG-aliphatic polyester copolymer.

聚乙二醇单甲醚和脂肪族环酯单体，在苯或甲苯溶剂中，在无水无氧，加热和搅拌的条件下，用辛酸亚锡为催化剂，开环聚合得到聚乙二醇单甲醚-脂肪族聚酯二嵌段共聚物。

The formation mechanism and the role of the solvents played were explored. Ethylene glycol was found to serve as the reducing agent while acetylacetone had effects on maintaining equilibrium conditions, suppressing the coalesces, enhancing the reducing ability of ethylene glycol, and directing the growth of multiply twinned palladium particles.

通过对产物形成的机理及溶剂所起的作用进行深入研究，发现乙二醇是还原剂，乙酰丙酮则具有维持平衡条件、减少团聚、增强乙二醇的还原能力及诱导钯多重孪晶的生长等作用。

For the asymmetric reduction ofα-hydroxyacetophenone and ethyl 4-chloro acetoacetate,-1-phenyl-1,2-ethanediol and-ethyl 4-chloro-3-hydroxybutanoate were produced by the purified enzyme, with the 99% and 94.3% e.e. value respectively.

在纯酶水平验证了近平滑假丝酵母(Candida parapsilosis CCTCCM203011)对外消旋苯基乙二醇的拆分机理，整个去消旋过程是由-苯基乙二醇次级醇脱氢酶和羰基还原酶共同催化完成的。

The term is often used for the simplest of the class, ethylene glycol (1,2-ethanediol).

甘醇一词，通常表示这种化合物中最简单的乙二醇(亦称1，2－乙二醇)。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。