The positive force of attraction of the electrons on the outside is greater and greater, and that pulls everything in.

所以对外层电子的吸引力,会越来越强，把电子们都向内吸引。

麻省理工公开课 - 固态化学导论课程节选

We're saying the probability of from the nucleus in some very thin shell that we describe by d r.

某一非常薄的壳层dr内,一个原子的概率,你想一个壳层时。

麻省理工公开课 - 化学原理课程节选

r And what that is the probability of finding an electron in some shell where we define the thickness as d r, some distance, r, from the nucleus.

在某个位置为,厚度为dr的壳层内,找到原子,的概率，我们来考虑下我们这里所说的。

麻省理工公开课 - 化学原理课程节选