用于鉴别羟基蒽醌类化合物的是() A.Borntrager’s反应 B.Kestin 发布时间:2017-05-02 17:22 │ 来源:www.tikuol.com 题型:单项选择题 问题: 用于鉴别羟基蒽醌类化合物的是()A.Borntrager’s反应B.Kesting-Craven反应C.Feigl反应D.金属离子反应E.无色亚甲蓝显色试验
题型:单项选择题 In order not to get into trouble, advertisers are increasingly cautious about taking out ads _____ children.[ ]A. being aimed at B. aimed atC. having aimed at D. having been aimed at 查看答案