bdb14黑人巨大视频,欧美精品欧美人与动人物牲交,精品国产一区二区三区AV色诱,内射极品少妇一区二区AV




Industrial hydrogen

Industrial hydrogen

Item name Index
The volume fraction of hydrogen (H2)/10 -2 ≥ 99.5
The volume fraction of oxygen (O2)/10 -2 ≤ 0.2
The volume fraction of nitrogen plus argon (N2+Ar)/10 -2 ≤ 0.3
Free water/(ml/40L bottle) No free water
CO/(ppm) CO+CO2<5
CO2/(ppm)
CH4/(ppm) Hydrocarbon <1000
C2H6/(ppm)

       Supply method:
       1.  Pipe car supply
       2.  Cylinder supply 
       3.  Large-scale pipeline supply