They used a liquid syrup of ipecac -- to do this.

VOA: special.2009.08.11

Real refrigerators actually work with liquids that go into gases so use the latent heat of the liquid, so it doesn't really work like the Joule-Thomson expansion. So this is real.

液体变成气体来工作,以运用液体的潜热，所以这不是,真正像焦耳-汤姆逊膨胀一样工作,这是真实的气体，不像焦耳。

麻省理工公开课 - 热力学与动力学课程节选

And the triple point of water is 16K that temperature and pressure - there's a unique temperature and pressure where water exists in equilibrium between the liquid phase, the vapor phase, and the solid phase.

与水的三相点,我们定义它为273。,水的三相点,是一个特定的温度和压强,可以使水的液态，气态和固态三相共同达到平衡，三相点是液态。

麻省理工公开课 - 热力学与动力学课程节选

Slowly bring the liquid to eighty-two degrees Celsius.

VOA: special.2010.08.02

So you need first to take the liquid helium and cool it below 53 degrees Kelvin before you can do the Joule-Thomson to cool it even further to make liquid helium.

我们首先需要,把温度江都53k一下,然后利用焦耳-汤姆孙实验,来继续冷却它。

麻省理工公开课 - 热力学与动力学课程节选