以非质子酸氯化亚锡为催化剂,催化合成了丁醛-1,2-丙二醇缩醛.Butyraldehyde 1,2 proparediol acetal was synthesized by using stannous chloride as catalyst.以非质子酸氯化亚锡为催化剂,催化合成了丁醛-1,2-丙二醇缩醛.Butyraldehyde 1,2 propanediol acetal was synthesized by using st...
The resonance scattering spectra of colibacillus have been studied.研究了大肠杆菌的共振散射光谱.The relative molecular mass of chitosan fractionated by wave was measured by the light scattering method.采用粘度法分析了不同溶剂对壳聚糖粘度的影响,用光散射法测定了超声波...
Several writers have posited the idea of a universal consciousness.有几个作者都假设存在普遍意识。She posited her hand on his shoulder.她把手搭在他肩膀上.He posited three basic laws of nature.他假设了三条基本的自然法则....
两栋小楼的底层已经彻底翻修过。The downstairs of the two little houses had been entirely refashioned.从底层干起，然后努力一步步升上去。Start at the bottom and try to work your way up.“身居高位很辛苦，”他说。“在底层更辛苦，”这个亿万富翁机敏地回答道。"It's tough at the top," he sa...
The president has been huddling with his most senior aides.总统一直在和最高层助理开私下碰头会。The president has been huddling with his most senior aides...总统一直在和最高层助理开私下碰头会。Twenty or thirty monkeys are huddling along the thick branch.三十只...