The reason that I wanted to point out this nodal plane here is because this is why it is called a pi orbital.

我指出这个节面的原因是因为,它就是为什么这个叫做π轨道的原因。

麻省理工公开课 - 化学原理课程节选

Well I was thinking it's the same reason on 9/11 with regard to the people who flew the plane into the Pennsylvania field as heroes because they chose to kill the people on the plane and not kill more people in big buildings.

我认为这和9·11的时候是一种情况1,那些让飞机在宾州坠毁的人，被视为英雄,因为他们选择了牺牲自己,而不是让飞机撞向大楼牺牲更多人。

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