The other chain is facing in the other direction, the 3' carbon is up, the 5' carbon is down.
对面的那条单链方向相反,3'位的碳原子向上,5'位的碳原子向下
So what that means is that we're limited in any atom to having two electrons per orbital, right, because for any orbital we can either have a spin up electron, a spin down electron, or both.
这意味着在一个原子内,每个轨道上可以有两个电子,对吧,因为对任何轨道,我们可以有自旋向上或者自选向下或者两者都有。
And, in any arbitrary crucible full of molten silver, half of them are going to be spin-up and half of them are going to be spin-down.
并且,在任一个浇满了熔银的坩埚中,银原子中的电子一半是向上转,另一半是向下转。
Figure out how you can make it move a little to the left, a little to the right, up and down and then repeat in some kind of looping structure.
就是找出办法让它向左移动一小步,向右移动一小步,向上一小步,向下一小步,像这样不断重复。
Dynamics then tells you why the object goes up, why the object goes down and why is it pulled down and so on.
而动力学则会告诉你为什么物体向上运动,为什么向下运动,为什么停下来,等等
They're colored different here to indicate one new difference that you know about now, and that's that there is an orientation, there's an up and down on the chain.
这里被涂成不同的颜色,来表示另一个不同之处,它是有方向的,表示双链一条向上,一条向下
But I think this is rather an implausible suggestion because, of course, you could have these glorious views just by going up in the airplane and looking down from the safety of your airplane.
但我认为这是个似是而非的建议,因为,当然,你可能只是坐飞机向上飞,并安全地向下看,就会有这些迷人的视野。
And that the fact that it split into two was telling them that there must be some new property to the electron, and what we call that now is either being spin up or spin down.
它能一分为二的,事实告诉我们,电子一定有某种新的性质,我们叫它自旋向上或者自旋向下。
Then he knows it's going to go up, it's going to curve, follow some kind of parabola, then his hands go there to receive it.
所以他就知道,这颗糖会先向上,再向下,沿着某条抛物线运动,然后他就能判断在哪里接住糖
The opposite leaflet does the other thing, the water soluble part points down and the fat points up, so now you have thin region of fat which is surrounded on both sides by water.
相反的部位则有不同的情况,水溶性部分向下,而脂肪向上,所以现在就得到了,两侧均被水包围的薄层脂肪区域
So this one is spin-up plus a half, this is spin-down minus a half.
所以自旋向上是正二分之一,而自旋向下是负二分之一。
So one goes spin-up and the other goes spin-down.
所以一个是自旋向上,另一个是自旋向下。
This is important because this molecule here, deoxyribose, is not the same upside down as it is - it's not symmetrical upside down and right side up, it's different because the 5' carbon's either pointed up or pointed down.
这很重要,因为对脱氧核糖来说,不都是像这样自上而下的,不是对称的自上向下或全部向上的,长链不同是由于,5'碳向上或者向下的指向不同
You are pushing down with the weight mg, and the floor has got to be pushing up with the mg, because the spring is not going anywhere.
你向下的作用力是重力 mg,然后地面向上的支持力也是 mg,因为弹簧现在根本没动
So the spring is being pushed by mg here and mg here.
所以弹簧受到一个向下的 mg 还有一个向上的 mg
Likewise with 2s, spin-up, spin-down.
s层也是这样,自旋向上,自旋向下。
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