Instead,these experts say, our planet is experiencing a normal series of temperature changes.

VOA: special.2010.01.19

The purpose here is to look at a series of processes in which temperature is held constant, and we're going to calculate how much work we get from allowing a gas to expand under various conditions.

目的是让大家了解一下,几个保持温度不变的过程，然后我们将计算,气体在不同膨胀过程中,的对外做功。

麻省理工公开课 - 热力学与动力学课程节选