You just change volume to pressure and basically you're looking at enthalpy under a constant -- anything that's done at a constant volume path with energy, there's the same thing happening under constant pressure path for enthalpy.

可以看到这就是把体积换成了压强,一般我们都是在一种恒定状态下,考虑焓的，任何在恒容条件下,能伴随能量变化的东西，也在恒压条件下伴随焓同样地变化,所以你可以经常。

麻省理工公开课 - 热力学与动力学课程节选

You know how pressure changes with temperature at constant volume if you know the equation of state.

如果你知道状态方程,知道在体积恒定的时压强如何随着温度变化。

麻省理工公开课 - 热力学与动力学课程节选

V So this nR over V. And then, using the relation again, T we can just write this as p over T.

恒定温度下的dp/dT等于nR除以，再次利用状态方程，可以把它写成p除以。

麻省理工公开课 - 热力学与动力学课程节选