"If you look at the content of Lech Kaczynski's policies, it was basically this sense of threat to Poland coming both from external sources, from Russia,from Germany, from the European Union."

VOA: standard.2010.06.17

p We want p equal to p external for the entire expansion, p2 and p external is decreased steadily from p1 to p2.

在膨胀过程中保持p等于外部，外部p很快从p1衰减到。

麻省理工公开课 - 热力学与动力学课程节选

So there's p v work and it's given by the integral minus p external dv or just the integral from one to two of dw.

我们知道对于pv系统来说,功w可以写成黑板上的两种不同形式。

麻省理工公开课 - 热力学与动力学课程节选