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 ...
a poor kid growing up in the ghetto在贫民区长大的穷孩子One of the most atmospheric corners of Prague is the old Jewish ghetto.古老的犹太人社区是布拉格最具特色的角落之一。Racism and crime still flourish in the ghetto.城市贫民区的种族主义和犯罪仍然十分猖獗。...
From the heart of America, this is the guarani spirit.巴拉圭:来自美洲的心脏, 就是瓜拉尼人的精神.Paraguay - The Guarani roars in South Bfrica!让瓜拉尼雄狮在南非怒号!The Wajapi of the Tupi - guarani cultural - linguistic group are indigenous to the nor...