他们打开金库, 拿走两袋钱,里面装有二十七万九千美元.They opened the vault, removed the two money bags containing $ 279,000.他走后我把信封打开,里面有1000美元的捐款.After he left opened the envelope and found it contained a $ 1,000 contribution....
传统的缩酮化、酯化反应工业上多采用浓硫酸作催化剂.Traditional ketalization and esterification reactions are usually catalyzed by concentrated acid in industry.对甲苯磺酸铜是乙二醇与羰基化合物缩醛(酮)化反应的高效催化剂.Acetalization of glycol with carbonyl compounds was car...