以下哪一味中药属麻醉中药( )
A.马钱子
B.川乌
C.罂粟壳
D.延胡索
E.雷公藤
参考答案:C
光激励荧光体中,为改变荧光体的结构和物理特性,常掺入的是()
A.Al3+
B.Eu2+
C.Cu2+
D.TI2+
E.Se2+
In your software development project you have to wait for 5 days after ordering a new software and then only you can start integration testing.The 5 days in this case is an example of ().
A.lead
B.lag
C.delay
D.float