Most direct substitution of groups bound to an aromatic nucleus is limited to diazonium salts.大多数连于芳核能被直接取代的基团仅限于重氮盐.Severe steric effects at the reactive carbon would impede the substitution.大的立体效应阻止在碳上的取代.We use saccha...
在斯堪的纳维亚神话里，月亮被赋予了男性身份。In Norse mythology the moon is personified as male.宪法还赋予巴西的25个成员州很大的权力。The constitution also confers large powers on Brazil's 25 constituent states.这条规定赋予了总统绝对及不受约束的权力。This provision gives the ...
The receiver and the quarterback are going to trade positions.接球手与四分卫将会对换位置。The line went dead. Whitlock replaced the receiver.线路中断了，惠特洛克把听筒放回原处。That's a heterodyne receiver.那是外差式接收机.That’s a heterodyne receiver.那是外...