Through nitrosation , hydrogenate reducion, and acylate three steps, the yield surpass 80 % for the diethyl malonate.收率相对于丙二酸二乙酯达到了80%以上.The necessary material of 2 - ( 2 - methoethyl ) acetaldehyde diethyl acetal was sy...
Their own lives already seemed to possess the symmetries of narrative art.他们自己的生活似乎已经拥有叙事艺术的对称性。This is in striking contrast with the symmetries to be discussed later.这与后面要讨论的对称性截然不同.Nuclei with closed - shell have spher...
When a drug permeates a cell, it must obviously traverse the cellular plasma membrane.当药物透过细胞时, 它显然必定要穿过胞浆膜.But can you traverse the stream?可是,你能闯过那车的洪流、人的洪流 吗 ?We traverse the desert by truck.我们乘卡车横穿沙漠.He cut his teeth ...
He lounged in an armchair in a stance of deliberate contempt.他懒洋洋地躺在扶手椅里,故意摆出一种轻蔑的架势.The fringes of the pundIt'set have already been intimating that these tainted - food incidents are deliberate.有人已经宣称这些食品遭到污染的事件是故意...
A cat can retract its claws, but a dog can’t.猫的爪子可以缩进去, 但狗不能。The fingers were gnarled, lumpy, with long, curving nails suggestive of animal claws.手指粗糙，关节突出，指甲又长又弯，让人想起动物的爪子。Chicken legs , chicken claws , laudatory title,...
这个发动机汇集了现代最顶尖的科技。This engine uses all the most modern technology.这册书是由一系列讲义汇集而成的.The book grew out of a series of lectures.这些事实汇集在一起足以构成一条不容置疑的理论.The facts added together to build up a theory which was indisputable....
The politician was ousted from office by a vote from members of his own party.那个政客被他自己党内的成员投票表决赶下台。If he demands too much, the unions will vote him down.如果他要求太多，工会就会投票撤换他。The proposal was defeated by just one vote.该提案仅以一...