And the temperature scale that turns out to be well-defined and ends up giving us the concept of an absolute zero is the ideal gas thermometer.

比如理想气体温标,它有精确的定义,并能引出绝对零度的概念,今天我们就先来谈谈它。

麻省理工公开课 - 热力学与动力学课程节选

And maybe if it some well-defined temperature and pressure.

这两个态可以具备确定的,温度和压强。

麻省理工公开课 - 热力学与动力学课程节选

the zeroth law, which is the common-sense law, which says that if you take a hot object next to a cold object, heat will flow from the hot to the cold in a way that is well defined, and it allows you to define temperature.

上节课我们讨论了，热力学第零定律,这一定律源自常识：如果把一个热的物体,与一个冷的物体挨在一起，热量就会以确定的方式。

麻省理工公开课 - 热力学与动力学课程节选

So in this experiment here, delta p is less than zero. You need to have this whole thing greater than zero. So delta T is less than zero as well. So if you're below the inversion temperature and you do the Joule-Thomson experiment, you're going to end up with something that's colder on this side than that side.

所以在这个实验中，Δp小于零,这全部都大于零,因此ΔT也小于零,所以如果在低于转变,温度的情况下做焦耳-汤姆孙实验,最后的结果是,这边的温度比这边低。

麻省理工公开课 - 热力学与动力学课程节选