,然后用液氮把氢气降温到,然后就可以使用这个氢气了，想要用氢气来做焦耳-汤姆孙实验。

Then you take hydrogen you cool it would liquid nitrogen to 77, then you can use your hydrogen gas.

youdao

,然后用液氮把氢气降温到,然后就可以使用这个氢气了，想要用氢气来做焦耳-汤姆孙实验。

Then you take hydrogen you cool it would liquid nitrogen to 77, then you can use your hydrogen gas.

youdao