用电解配氧法配置微量氧标准气,应首先将被测气体通过脱氧触媒,把其中的含氧量脱除到最低限度,得到所谓的()。
A、量程气
B、零点气
C、参比气
D、测量气
参考答案:B
— How will I ____ you at the airport?
— Well, I'm wearing a hat and I've got a big black um-brella with me. [ ]
A. recognize
B. notice
C. know
D. realize
最易发生幽门梗阻的溃疡是
A.胃窦部溃疡
B.十二指肠壶腹溃疡
C.幽门管溃疡
D.壶腹后溃疡
E.复合性溃疡