空调冷水机组操作规程中准备工作包括什么?
参考答案:
检查冷冻泵、冷却泵进出水阀是否全部开启;检查系统水压正常;检查油温、油位正常,电源电压380V±10℅。
NA表示阿伏加德罗常数,下列说法正确的是( )
A.1 mol•L-1 盐酸中含有的氯化氢分子数为NA
B.标准状况下,22.4L的SO2气体中含有的氧原子数为2NA
C.1L1.0 mol•L-1CH3COOH溶液中含有的H+数一定为NA
D.2.7g Al在与足量盐酸反应中失电子数为0.3NA
Which of the following is NOT true about the new capital according to the report
A.It’s in the center area of South Korea.
B.It has excellent transport and environmental conditions.
C.The relocation will cost $94 million.
D.It is not named yet.