她歌喉甜美,音域奇广.She has a marvellous voice with an extraordinary range.至少可以说,她的音域不够宽,而且令人不舒服的是,她总是音高偏低。Her vocal range was, to say the least of it, limited, and she had a distressing tendency to sing flat.钢琴的音域比人声的音域更大.A pian...
NMA was hydrogenated to 3 - amino - 4 - methoxyacetanilide ( AMA ) with S - Ni as catalystin liquid phase.以改性的骨架镍为催化剂催化3-硝基-4-甲氧基乙酰苯胺(NMA)液相选择性加氢制备了 3- 氨基 -4- 甲氧基乙酰苯胺 ( AMA ).Isoprene could be deeply hydrogenated to isop...