It's constant pressure. OK, so now, last time you looked at the Joule expansion to teach you how to relate derivatives like du/dV.

这是恒压的，好，上节课你们,学习了焦耳定律,以及怎样进行导数间的变换。

麻省理工公开课 - 热力学与动力学课程节选

And this is--God, I love this--one picture, you first see the first picture you can actually see of Paris, the faubourg du temple.

这个是,天啊,我爱死这张了,这是你能看到的巴黎的第一张照片,在圣殿郊区街拍的

耶鲁公开课 - 1871年后的法国课程节选

du If you measure something else, you won't get du.

如果你测量其它量，得到的就不是。

麻省理工公开课 - 热力学与动力学课程节选

I suggested that there was a critical response to those issues that was somewhat negative, and I want to sort of remind you of that from W. E. B. Du Bois's review of Black Boy when it came out.

对于负面问题,有个关键评述，大家看一下,关于《黑孩子》的评论。

耶鲁公开课 - 1945年后的美国小说课程节选

v du/dV under constant temperature. du/dT v under constant volume. You use the Joule expansion to find these quantities.

像偏u偏v，恒温下的偏u偏,恒容下的偏u偏,你们知道怎么运用焦耳定律。

麻省理工公开课 - 热力学与动力学课程节选

If you have a real gas and you write du is Cv dT and your path is not a constant volume path, then you are making a mistake. But for an ideal gas, you can always write this. And this turns out to be very useful to remember.

对于真实气体，如果其变化过程,不是恒容的，du=Cv*dT就不成立，但对于理想气体,这条规则永远成立,这一点非常有用，请记住。

麻省理工公开课 - 热力学与动力学课程节选

du But here you've got pressure constant. du, T this is du, not H here. du/dT is only equal Cv to Cv when the volume is constant, not when the pressure is constant.

这里是压强横笛，du，这是，不是H，偏U偏,只在体积恒定时等于，而不是压强恒定时。

麻省理工公开课 - 热力学与动力学课程节选

The split voice, the development of what you could say is that racial double consciousness that W. E. B. Du Bois talks about, that double consciousness of the racial reality, is manifested in that split in the narrative.

在双重叙述中,双重语气表现了出来,这就是W。，E。，B，Du，Bois所说的，种族双重意识，的发展。

耶鲁公开课 - 1945年后的美国小说课程节选