So it already should make sense why we have that p orbital there, in order to form a pi bond, we're going to need a p orbital.

这里有p轨道是很合理的,为什么我们在这里有P轨道，为了形成一个π键，我们需要一个p轨道。

youdao

PCNA-index(PI) in the high ligation groups were much lower than the control groups(P<0.01), while apoptosis index(AI) were higher than the control groups (P<0.01).

结扎组生精细胞PCNA增殖指数（PI）明显低于对照组（P<0.01），凋亡细胞指数（AI）明显高于对照组（P<0.01）。

youdao

px So we're talking about pi carbon 2 p x, 2px because it's the x axes combining to carbon 2 p x.

我们讨论的是π碳，因为它在x轴结合成碳。

麻省理工公开课 - 化学原理课程节选

px 2py So we need to fill all the way up to the pi 2 p x, and the pi 2 p y.

我们需要填到。

麻省理工公开课 - 化学原理课程节选

So let's fill it out in this way, 2p keeping in mind that we're going to fill sigma out the pi 2 p's before the sigma.

让我们这样填上去，记住我们先填π,轨道再填。

麻省理工公开课 - 化学原理课程节选