乙二醛

Under these conditions,the yield of butyraldehyde glycol acetal was 68.1%.

在此优化条件下，丁醛乙二醇缩醛的收率可达68.1%。

The optimum conditions were determined as follows:the molar ratio of butyraldehyde to glycol was 1∶1.6,the mass ratio of catalyst to reactants was 0.4%,the volume of cyclohexane as the water-carrying agent was 10 mL,and the reaction time was 60 min.

结果表明，磷钨钼杂多酸对合成丁醛乙二醇缩醛有较好的催化活性，适宜的反应条件如下：n∶n=1∶1.6、催化剂用量为反应物料总质量的0.4%、带水剂环己烷用量为10 mL、反应时间为60 min。

Main business scope: polyformaldehyde methylal methanol sodium nitrite sodium sulfide protopine xylene glacial acetic acid soda ash Ethyl acetate ion-exchange membrane caustic soda Chloromethane AEO-9 polyethylene glycol and other major raw materials and products.

多聚甲醛甲醇甲缩醛亚硝酸钠硫化碱片碱二甲苯纯碱冰醋酸醋酸乙酯离子膜烧碱 AEO-9 氯甲烷聚乙二醇等主要原料和产品。

Ethylene glycol glycosides,useful as humectant in cosmetics,were prepared by phosphoric acid-catalyzed acetalization of glucose with ethylene glycol.

在磷酸催化下，由葡萄糖和乙二醇经缩醛化反应制备了乙二醇葡糖苷，可用作化妆品保湿剂。

Vanillin 58 was used as starting material, which underwent methylation, bromination, acetalization, lithiation followed by nucleophlic addition to aldehyde, Diels-Alder reaction, selective reduction and lactonization to produce diphyllin in an overall yield of 38%(7 steps).

这个方法从香兰素58开始，经过甲基化、溴化、成乙二醇缩醛反应、锂化而后对醛亲核加成、Diels-Alder反应、选择性还原反应和内酯化反应共7步，最后得到diphyllin，总产率38％。

The volume ratio of furaldehyde to acetic anhydride is 1∶2; the mole ratio of furaldehyde with anhydrous potassium carbonate is 1.00∶0.54. The best phase transfer catalyst is PEG1000, the mass ratio of PEG1000 with furaldehyde is 4.3%, the reaction time is 11 min, the reaction power of microwave is 260 W. The yield ofα-furanacrylicacid is up to 72.3% under these reaction conditions.

研究结果表明：在微波辐射功率为260 W、微波反应时间为11 min、以聚乙二醇1 000(PEG1000)为相转移催化剂，糠醛与乙酐的体积比为1∶2，糠醛与无水碳酸钾的量比为1.00∶0.55时，α-呋喃丙烯酸的产率为72.3%。

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%。

The synthetic condition s of benzaldehyde and glycol acetals by 732#strong acidic ion exchange resin are studied.

研究了苯甲醛与乙二醇在732#强酸性阳离子交换树脂催化下的合成条件，得到了缩醛化反应的最佳合成条件：醛/醇摩尔比为1∶1。

Some technologies,including olefines from methanol,oxalates and ethylene glycol from carbon monoxide,carbon dioxide-based polymers,chemicals from the syngas prepared by biomass gasification,acetone and butanol by fermentation,and chemicals from acetylene,ethanol,glycerol,furfural,hydroxymethyl furfural and starch,were reviewed.

包括甲醇制烯烃，一氧化碳制草酸酯和乙二醇，乙炔化学品，二氧化碳聚合物，生物质气化合成化工产品，发酵法生产丙酮、丁醇，乙醇衍生化工产品，甘油合成化工产品，糠醛和羟甲基糠醛合成化工产品，淀粉合成化工产品等重要的石油替代化学品生产技术被介绍。

Mascagni were held into a solution containing calcium, ethylene glycol bis-amino tetmacetate and water, respectively. The effects of calcium were studied by measuring the ornamental quality of cut flowers and the physiological characteristics such as calmodulin, abscisic acid, gibberellins, zeatin, endogenous calcium, malondialdehyde and soluble sugar in florets.

以唐菖蒲红色品种'马加烈'切花为材料，瓶插在含有乙酸钙或钙离子专一性螯合剂乙二醇二乙醚二胺四乙酸的溶液中，分析乙酸钙对切花观赏品质的影响以及第1和第3朵小花内钙调素、脱落酸、赤霉素、玉米素、Ca(上标 2+)、丙二醛和可溶性糖含量的变化。

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。