N-(1-萘基)乙二胺偶氮分光光度法测定水中苯胺类倾倒中物时,对色泽很深的废水样品,应采用蒸馏法,消除其干扰。
参考答案:错
解析:若水样颜色深,可用聚已内酰胺粉末脱色。
.Polly found herself_________ up at a man_________with his hand___________on her arm.
A.staring; standing; resting
B.stared; stood; rested
C.stare; stood; rested
D.to stare; standing; resting
下列作家中由北齐、北周入隋的有______
A.虞世基
B.薛道衡
C.卢思道
D.王绩
E.杨素