Is this possible? That's what the first law says it's possible; work is heat, and heat is work, and they're the same thing. You can break even 100% maybe. So let's go back and see what work is.

00%的效率,我们可以从大气中吸收热量，用来驱动我们的汽车,效率也应该能达到。

麻省理工公开课 - 热力学与动力学课程节选

So the expansion against lower pressure draws less heat from the hot reservoir right.

所以压强较低时的膨胀,从高温热源吸收的热量更少。

麻省理工公开课 - 热力学与动力学课程节选

OK, so that means heat is being imparted to the system, right, from the surroundings in a manner that compensates exactly the amount of work done.

好，这表示系统,从外界吸热,吸收的热量与系统,对外做功的值相等。

麻省理工公开课 - 热力学与动力学课程节选

This is why people right tables and tables of H delta H's. Why you have delta H's from all these reactions, because this is basically the heat and the heat is something we can measure, we can control. We can figure out how much heat is going in and out of something.

这就是为什么人们一再提出ΔH的原因,为什么在所有的反应中你都能看到Δ,因为它就是热量，而且热量,是一种我们可以测量并且控制的东西，我们可以测量出有多少热量,从一些东西里面放出或被吸收。

麻省理工公开课 - 热力学与动力学课程节选