supercritical helium

例句：

1. 1.The supercritical helium is used in the production of liquefied natural gas.
   超临界氦气用于液化天然气的生产。
2. 2. The supercritical helium is a key component in the refrigeration system.
   超临界氦气是制冷系统的关键成分。
3. 3. The supercritical helium is used to cool down the liquid nitrogen.
   超临界氦气用于冷却液态氮。