So the point is, this balance between energy thatyou could think of as say bond energies in chemical reactions, and entropy that you can think of in terms of disorder, how many different possible combinations or configurations of something wrong, will dictate where the equilibrium lies.

关键在于，这种能量与熵之间的平衡,确定了平衡的条件，在化学中能量涉及键能，而熵和无序有关,即有多少可能的不同组合或者形位，二者的平衡会告诉我们平衡态是什么样子。

麻省理工公开课 - 热力学与动力学课程节选

So we immediately get du at constant S and V is less than zero.

这样我们马上就得到以下结论：,在等熵，等容条件下dU必须小于零。

麻省理工公开课 - 热力学与动力学课程节选

Now, we can immediately see what du/dV at constant entropy is.

我们能够很容易看出,恒定熵的条件下du/dV的数值。

麻省理工公开课 - 热力学与动力学课程节选