乙酸

The kinetics of catalytic synthesis of ethyl acetate using cation exchange membrane catalyst was studied.

摘 要：研究了以阳离子交换树脂为催化剂合成乙酸乙酯的动力学。

The results show that these derivatives can be obtained in the yield of over 90％ in the presence of DMF when using ethyl acetate as a catalyst.

结果表明，以N，N-二甲基甲酰胺为溶剂，以乙酸乙酯为催化剂的合成路线，均可以以90％以上的得率合成出上述化合物。

The calculated IC times of chl-a in ethyl acetate, tetrahydrofuran and dimethyl formamide are 141, 147, and 241 fs, respectively.

计算得到的叶绿素a分子在乙酸乙酯、四氢呋喃和二甲基甲酰胺溶剂中的内转换时间分别是141、147和241 fs。

AIM To investigate the therapeutic effect of ethyl acetate extract from Pongamia pinnata roots on ethanol-induced gastric lesions.

目的研究水黄皮根乙酸乙酯萃取物对乙醇致胃黏膜损伤的治疗作用。

Make solutions of 4:1, 1:1, and 1:4 ratios of hexane:ethyl acetate.

配制一个4：1，1：1和1：4的己烷：乙酸乙酯的溶液。

Then the solution is heated to the temperature at which the caffeine and either methylene chloride or ethyl acetate compounds evaporate.

那么，解决办法是加热温度的咖啡因，或是二氯甲烷或乙酸乙酯化合物蒸发。

European or Traditional Process - Direct Method: The direct process involves softening the beans by steam first, then washing them for about 10 hours with either a methylene chloride or ethyl acetate solution to absorb the caffeine from the bean.

欧洲或传统工艺-直接方法：直接过程涉及软化咖啡豆的蒸汽，然后洗涤他们大约10小时带有二氯甲烷或乙酸乙酯溶液吸收咖啡因的咖啡豆。

And the operational condition was as follows: 100-200 mesh silica gel to be the stationary phase, solvent system of methlene chloride: ethyl acetate: ethanol = 80:35:5 to be the eluent, the flow rate of the eluent to be 2.0 mL/min, the feeding concentration of pristinamycins to be 2.26 g/L, the total loading amount of the silica gel to be 0.81 mg/g and the temperature to be 25℃.

优化后的柱层析操作条件为：选用100～200目的硅胶，二氯甲烷：乙酸乙酯：乙醇=80：35：5为洗脱剂，流速为2.0 mL／min，普那霉素的进样浓度为2.26g／L，硅胶的总负载量约为0.81 mg／g，温度为25℃。

At the same concentration, extracts show the highest scavenging rate on the four different free radicals extracted by ethyl ether, acetone, ethyl ether and ethyl acetate, respectively.

在相同的浓度下，对自由基的清除作用最大的分别为乙醚、丙酮、乙醚和乙酸乙酯提取物。

The effects of different entrainers(methanol,acetone,ethyl acetate,petroleum ether and ethanol of different concentrations) on the diosgenin extraction rate were studied.

探讨了乙醇、甲醇、丙酮、乙酸乙酯、石油醚作为夹带剂以及在无夹带剂的条件下，对薯蓣皂素收率的影响。

Singer Leona Lewis and former Led Zeppelin guitarist Jimmy Page emerged as the bus transformed into a grass-covered carnival float, and the pair combined for a rendition of "Whole Lotta Love".

歌手leona刘易斯和前率领的飞艇的吉他手吉米页出现巴士转化为基层所涵盖的嘉年华花车，和一双合并为一移交&整个lotta爱&。

This is Kate, and that's Erin.

这是凯特，那个是爱朗。