Polyether - type isocyanate prepolymers are prepared with polyether polyols and tolylene diisocyanate.采用聚醚多元醇和甲苯二异氰酸酯合成了聚醚型异氰酸酯预聚体.A polyamide imide was synthesized from trimellitic anhydride and di isocyanate.本文用偏苯三酸酐和二...
The hut isn't safe; it was just flung together.这个棚子不安全, 它不过是匆忙搭起来的.The poor old man lived in a little wooden hut.那个贫穷的老人住在一间小木屋内.The hut was constructed from trees that grew in the nearby forest.这棚屋是用附近森林里长的树木建造的....