液化石油气瓶阀的公称工作压力为()MPa。
A.1.5
B.2.0
C.2.5
D.3.5
参考答案:C
A University is_____ place where you can learn to be wise, learn to be confident and learn
to make _____ difference.[ ]
A. a; /
B. a; a
C. the; /
D. the; the
某石油精炼厂自平均有效源高60m处排放的SO2量为80g/s,有效源高处的平均风速为6m/s,估算冬季阴天正下风向距离烟囱500m处地面上的SO2浓度为()。(稳定度为D时,x=500m,σy=35.3m,σZ=18.1m)
A.27.3μg/m3
B.20.5mg/m3
C.13.5μg/m3
D.32.3mg/m3