一缩二乙二醇

Two magnetic triphase catalysts of comb-like polyether s supported by γ-Fe2O3 were synthesized, and their catalytic behaviors in the iodo-substitution, etherization and the addition reaction of dichlo-rocarbene to styrene were also investigated.

以表面经偶联剂修饰的γ-Fe2O3为载体，通过聚分别与乙二醇单甲醚和一缩二乙二醇单甲醚的醇钠盐反应，合成了两种磁性梳状聚醚三相相转移催化剂，研究了它们在碘代、二氯卡宾对双键加成和混合醚制备反应中的催化活性。

PES/NMP were used as the model membrane-forming system, H〓, 1butanol, and diethylene glycol (as well as isopropanol and ethylene glycol) was selected as nonsolvent additives.

本文选取PES/NMP为制膜体系，研究NSA——水、正丁醇、一缩二乙二醇在浸入凝胶成膜过程中的作用。

Organic substances (diethylene glycol, glycol methyl ether and methyl ethyl ketone) were used as nonsolvent additives and N-methyl-2-pyrrolidone used as a solvent in membrane preparation. The effects of PPESK concentration, the type of additives and the NSA concentration in casting solution on the morphology and performance of the PPESK hollow fiber ultrafiltration membrane were systematically investigated.

以PPESK为膜材料，NMP为溶剂，水为凝胶剂，选用乙二醇甲醚、一缩二乙二醇和丁酮为非溶剂添加剂，系统研究了聚合物浓度、添加剂种类和含量对PPESK中空纤维超滤膜结构和性能的影响，制备了一系列具有不同孔径和通量的中空纤维超滤膜。

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 surface hydroxyl group onto magnetic polyvinyl acetate nanoparticles can be obtained by saponification reaction on their surface.

结果表明，磁性聚苯乙烯颗粒与丁二酸酐发生Freidel-Crafts酰基化反应，可以在颗粒表面引入少量羧基；磁性聚甲基丙烯酸甲酯颗粒分别与乙二醇、二缩三乙二醇、聚乙二醇等发生醇-酯交换反应，可以在颗粒表面接枝不同分子链长度的末端羟基；磁性聚醋酸乙烯酯颗粒经过醇解或皂化反应可以获得表面羟基；磁性聚丙烯酸甲酯颗粒通过乙二胺或1，6己二胺的胺解反应可以得到表面氨基，继而与一氯乙酸反应可以引入亚胺二乙酸基团。

Thus, in order to attain acetal can be used as precursor of its matrix olefine aldehyde, 2-undecental glycol acetal was synthesized, and the corresponding optimum reaction conditions as: 2-undecental 0.2mol, glycol 0.3mol, cyclohexane as solvent, catalysed by vitamin C, the optium reaction time was 6h, its reaction yield could reach over 77.25%.

为了进一步探求效果更理想的前体化合物，本文继续合成了2-十一烯醛乙二醇缩醛，通过单因素优化实验得到最佳反应条件为：环己烷作溶剂，VC作催化剂，用量0.42%，醛醇物质的量之比0.2：0.3，反应时间6h，此条件下产品收率达77.25%。

Flame—retardant resin was prepared by the condensation and polymerization of phosphoric acid, trihydroxy methyl propane and epoxy chloropropane,the resin was then reacted with hexane diacid and diglycol under certain condition ,resulting in polyol containing 1.5% P and 17— 18% polyester polyol, which was foamed with polyisocyanate, water and catalyst by one— step method, producing fire...

通过磷酸、三羟甲基丙烷和环氧氯丙烷的缩合和聚合反应制得阻燃树脂，然后将它与己二酸、一缩二乙二醇在一定条件下反应制得含P1.5%和含Cl17～18%的聚酯多元醇，再将它与多异氰酸酯、水、催化剂等组分采用一步法发泡工艺制得阻燃聚氨酯软泡塑料。

Flame— retardant resin was prepared by the condensation and polymerization of phosphoric acid, trihydroxy methyl propane and epoxy chloropropane,the resin was then reacted with hexane diacid and diglycol under certain condition ,resulting in polyol containing 1.5% P and 17— 18% polyester polyol, which was foamed with polyisocyanate, water and catalyst by one— step method, producing fire—resistant PU soft foam.

通过磷酸、三羟甲基丙烷和环氧氯丙烷的缩合和聚合反应制得阻燃树脂，然后将它与己二酸、一缩二乙二醇在一定条件下反应制得含P1.5%和含Cl17～18%的聚酯多元醇，再将它与多异氰酸酯、水、催化剂等组分采用一步法发泡工艺制得阻燃聚氨酯软泡塑料。

The synthesis of alkylcyclohexylbenzoic acid: take the synthesis of ethylcyclohexylbenzoic acid as a typical example. With the AlCl3 as the catalyst, cis+trans acetylcyclohexylbenzene is synthesized from the reaction of acetyl chloride, cyclohexene and benzene.

烷基环己基苯甲酸的合成研究：主要研究了乙基环己基苯甲酸的合成，以乙酰氯、环己烯、苯为原料，三氯化铝为催化剂，合成乙酰基环己基苯，用水合肼、氢氧化钾、一缩二乙二醇经过高温加热还原羰基(Wolff-黄鸣龙还原)，将所得到的乙基环己基苯用乙酰氯进行傅克酰基化得到乙基环己基苯乙酮，所得中间体经过处理之后直接得到反式产物，将反式异构体的乙酰基氧化得到反式烷基环己基苯甲酸。

An improved chemical method for the determination of the molar substitution degree of hydroxyethyl guar gum has been described.

本文用模型小分子一缩二乙二醇的醚键断裂实验证明了可行性，羟乙基瓜尔胶上的羟乙基链段与过量对甲苯磺酸-乙酸酐在130℃下反应14hr，醚键完全断裂生成酯，并在pH=11条件下煮沸1hr使酯完全水解，转变为乙二醇。

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。