And if all of the possible brackets were filled out on standard paper and stacked on top of each other, how big would the pile be?" It would actually go from the earth to the moon and back,1.1 million times,".

VOA: standard.2009.03.25

A state where it's closed, so imagine a channel with a lid on top of it; when it's closed nothing can go through the channel, when it's open then things can go through.

一种是闭合状态,想想一个有盖子的通道吧,当盖子合上的时候任何东西都不能通过,而打开时就畅通无阻

耶鲁公开课 - 生物医学工程探索课程节选

If you go to the very top of Kearny, there's Coit Tower up on the hill there. That's really cool.

如果你走到干尼街的尽头，就会看到山顶上的科伊特塔。那里很棒。

旧金山的热点 - SpeakingMax英语口语达人

s And if we go ahead and superimpose the 3 s on top of the 3 p, you can see that the 3 s actually has some bit of probability density that gets even closer to the nucleus than the 3 p did.

如果我们继续将,重叠到3p上面，你们会看到3s事实上,有一点概率密度,距离原子核更近,比3p轨道。

麻省理工公开课 - 化学原理课程节选