So you can see, if it's spinning on its own axis in this direction we'd call it spin up, where as this way it would be what we call spin down.

你们可以看到，如果它绕自己的轴朝这个方向转,我们就说它是自旋朝上，这个方向我们叫它自旋朝下。

麻省理工公开课 - 化学原理课程节选

The fact that when you go in a circle, you accelerate is what we're learning here, coming from the fact that velocity is a vector and its change can be due to change in the magnitude or change in direction.

而当你做圆周运动时你也在加速,这是我们在这里所学到的,原因就在于,速度是一个矢量,其变化可以通过改变模长,或者方向来实现

耶鲁公开课 - 基础物理课程节选

One, its chain is oriented in the opposite direction: where this one goes 5' to 3', this one goes 3' to 5'.

一,这些DNA单链,方向相反,一条从5'端到 3'端,另一条从3'端到5'端

耶鲁公开课 - 生物医学工程探索课程节选