I have shown that by taking Avogadro's number of individual ion pairs and putting them all together in a line, the system's energy became more negative.

我推导出了,从每一个离子对中抽出阿伏加德罗常数,再把它们放在一起在一列中，这个系统的能量就变得更负。

麻省理工公开课 - 固态化学导论课程节选

That's the work that the system is doing to the environment. I'm doing work to the environment. The work is negative, which means that work is being done to the environment.

功的大小,就是矩形的面积,这样我们就实现了一台热机，冷却，加热，加热,冷却，系统回到了初态。

麻省理工公开课 - 热力学与动力学课程节选

All the energies are negative because it is a bound system. I start up here with n equals one.

所有能量级都是负数，因为它是一个束缚系统,在这里我从n等于1讲起。

麻省理工公开课 - 固态化学导论课程节选

So that's a negative feedback control system.

这就是负反馈控制系统得名的原因

耶鲁公开课 - 生物医学工程探索课程节选

So you don't want to put in a negative energy, that's not going to help you out, you need to put in positive energy to get an electron out of the system. So that's why you'll find binding energies are always negative, and ionization energies are always going to be positive, or you could look at the equation and see it from there as well.

因为这对电离没有帮助,你需要一个正的能量,使得电子脱离这个系统,这就是为什么你会发现,结合能总是负的而电离能总是正的,或者你们看这个方程也可以发现这一点。

麻省理工公开课 - 化学原理课程节选

The two analogies we use " was strengthening our immune system or stronger "psychological engine" that has the capacity to endure more not just from the negative to zero, but also from the zero to the positive.

我们使用的两个类比,是加强我们的免役系统或加强“心理引擎“,获得更强大的忍受能力,不只是从负到零，还要从零到正。

哈佛公开课 - 幸福课课程节选

Delta v is positive in this direction here, the work is negative. So work on the system is positive. Work done by the system is negative.

功是负的，总而言之,外界对系统做功的符号为正。

麻省理工公开课 - 热力学与动力学课程节选

It is a conservative system so all the energies are negative.

它是一个保守系统,所以所有的能量级都是负值。

麻省理工公开课 - 固态化学导论课程节选