报道以呋喃甲醛和苯乙酮为原料,氢氧化钠为催化剂,采用超声波辐射合成糠叉乙酰苯的方法.With furfural and acetophenone as raw materials - furfurylideneacetophenone was synthesized by NaOH as catalyst under ultrasonic irradiation....
Since then, it has been wildly used in the area of aerospacecraft, aircraft, energy system, electronics, automobile, mechanical equipment et al.由于综合性能优异, 问世后很快在航天 、 航空 、 能源 、 电子 、 汽车 、 机械等领域得到了成功的应用....
Evidently no lessons have been learnt or else the government would not have handled the problem so sloppily.政府显然没有吸取教训，不然不会把问题处理得那么草率。I must enroll the children for piano lessons before next week.我必须在本周内给孩子们报名学钢琴课.This l...