下列乙酰化试剂,酰化能力最强的是( )
A.冰乙酸
B.醋酐
C.浓硫酸
D.乙酸酯
E.乙酰氯
参考答案:E
The town official broke ________ for working over time in the search for the trapped people after the earthquake.
A.out
B.away
C.down
D.into
元代山水画家()提出:“作画大要,去邪、甜、俗、赖四字。”()
A.王蒙
B.黄公望
C.倪瓒
D.吴镇