They're less shielded because they're closer to the nucleus, they feel a greater z effective.

它们受到少的屏蔽,因为它们离原子核更近，它们感觉到一个更大的有效电荷量。

麻省理工公开课 - 化学原理课程节选

A kind of consequence of this is if we're thinking about a multi-electron atom, which we'll get to in a minute where electrons can shield each other from the pull of the nucleus, we're going to say that the electrons in the s orbitals are actually the least shielded.

这样的一个后果就是,如果我们考虑一个多电子原子，我们等会就会讨论到它,电子会互相,屏蔽原子核的吸引，我们说ｓ轨道电子,更不容易被屏蔽。

麻省理工公开课 - 化学原理课程节选

And for the s electron, since it can get closer, what we're going to see is that s electrons are actually less shielded than the corresponding p electrons.

对于s电子，因为它可以离得更近，我们可以看到s电子事实上,相对于p电子受到,更少的屏蔽。

麻省理工公开课 - 化学原理课程节选