dT/dp is mu JT. So for a real gas like air, this is a positive number. It's not zero.

所以对于像空气这样的真实气体，这是一个正数，不等于零。

麻省理工公开课 - 热力学与动力学课程节选

But a real key in looking at these plots is where we, in fact, did go through zero and have this zero probability density.

是我们经历这些零值,而且有这些零概率密度,我们把它叫做节点。

麻省理工公开课 - 化学原理课程节选

u=0 And it's approximately equal to zero for all real gas processes.

在所有理想气体绝热过程中Δ,对真实气体近似为零。

麻省理工公开课 - 热力学与动力学课程节选

Well recall from week zero when we took a very real world phonebook and then just last week we had our volunteer come up with the array of pieces of paper on the board and when I challenged myself and when I challenged our volunteer to find me the number 50 both he and I were able 50 to leverage one assumption.

大家回忆一下,当我们拿着一个现实世界的电话簿,就在上周我们的志愿者,在黑板上提出了纸片的阵列,我挑战自己，也挑战志愿者,要找出同一个,数字。

哈佛公开课 - 计算机科学课程节选