The carbon is electrophilic centre.碳是亲电的中心.It will become deepen to the students'recognization in mechanism of Aryl electrophilic substitution.这些问题的讨论将深化学生对芳烃亲电取代反应机理的认识.The rate constants of radical and electrophil...
The human population swelled, at least temporarily, as migrants moved south.随着移居者南移，人口出现膨胀，至少是暂时性膨胀。There are approximately 12 million migrants with their dependants living in the EU countries.大约有1200万流动工人带着家属居住在欧盟诸国.He ...