采用1,4- 丁二醇 、 马来酸酐及十八醇为主要原料,合成出一种双子表面活性剂1, 4- 丁二醇双琥珀酸十八醇双酯磺酸钠.A new type gemini surfactant was synthesized from 1,4 - butanediol , maleic anhydride and 1 - octadecanol.研究了加入聚对苯二甲酸丁二醇酯(PBT) 对酚醛塑料的增韧改性.A phenolic resin was ...
There is nothing in the rules of grammar to suggest that ending a sentence with a preposition is wrong.语法规则中并没有规定句子以介词结尾是错误的。...the difference between Sanskrit and English grammar.梵文语法与英文语法的区别Beginners are too apt to mak...
中世纪时，drab（“本色布”）一词指的是一种农民用来制衣的非常普通的羊毛织物。In the Middle Ages the term "drab" denoted a very simple type of woollen cloth which was used by peasants to make their clothes.第七届广州国际纺织及制衣工业展览会开幕仪式现在开始!The opening ceremony of Ca...