色谱柱理论塔板数计算公式n=5.54(tR/Wb/2)2中,各符号的含义是
Wb/2
A.峰面积B.峰高C.保留时间D.峰宽E.半高峰宽
参考答案:E
_____ the moonlight they cooked the meat _____ an open fire.
A.To; over
B.From; in
C.In; near
D.By; on
有如下器材:①瓶盖起子,②剪铁皮的剪刀,③天平,④定滑轮,⑤镊子,⑥钓鱼竿.其中属于省力杠杆的有______;属于费力杠杆的有______;属于等臂杠杆的有______(以上各空填序号).