Medicine intermediate N - ethylethylenediamine ( NEED ) was synthesized from acrylamide and ethylamine by addition reaction and Hofmann rearrangement.以丙烯酰胺为起始原料,经乙胺加成后,再经Hofmann重排两步反应后合成了药物中间体N - 乙基乙二胺 ( NEED )....
The match looks like being a David and Goliath contest.比赛看上去像是一场力量悬殊的较量。The other bidders for the contract complained that it had not been a fair contest.其他竞标人抱怨说该合同的竞标不公平.It is still a close contest between two leading ...
On the customs declaration, the sender labeled the freight as agricultural machinery.在报关单上，寄货人将货物列为农用机械。The railways will carry a far higher proportion of freight traffic.铁路将承担比例高得多的货运量。Environmental pressures are streng...