生产装置检修前停工的五个要求是什么?
参考答案:
(1)生产装置停得稳;
(2)设备压力要放空;
(3)管线设备要吹扫干净;
(4)动力电源要拉开;
(5)法兰阀门盲得住。
中性粒细胞的分化发育主要需要()
A.CFU
B.GM-CSF
C.TSGF
D.BFU
E.EPO
He did all he could to _______ but nobody noticed him.
A.draw people’s attention
B.focus his attention
C.draw attention to
D.pay attention