在除去脂溶性生物碱的碱水中,提取水溶性生物碱宜用( )。
A. 酸化后乙醇提取
B. 乙醇直接从碱水提取
C. 丙酮直接从碱水提取
D. 正丁醇直接从碱水提取
查看答案
下列哪些性质可用于生物碱的分离( )。
A. 酸性
B. 碱性
C. 极性
D. 溶解度
E. 旋光性
麻黄碱、烟碱具有挥发性,可用( )法提取;咖啡因具有( )性。
Choose the most appropriate word or phrase to complete each of the following sentences.The claims have received independent _______ from a team of experts.
A. contamination
B. confirmation
C. adolescence
D. nonsense
The Prime Minister is to meet his European _______ to discuss the war against drugs.
A. disbelief
B. counterpart
C. fitness
D. mortality