A turbulent flow is self-similar if there is an energy cascade.

湍流是在不同级上是自相似。

They're not all from different elements, most of them are from different energy levels in just a few elements.

它们并非都来自不同元素，大多数来自少数元素中不同级。

I still remember that picture where there is a quantum well and the levels of electrons confined in the quantum well.

我仍然记得那张图⽚，其中有⼀⼦和限制在⼦中电⼦级。

Objects with lower density, like stuff that's made of organic materials, will allow more of the lower-energy X-rays to pass through.

低密度东西，像有机材质东西，会让低级X射线穿过。

The electrons could only orbit at precisely those levels, and so they couldn’t spiral inwards.

电子只在特定级上运动，因此它们不会向内螺旋坠落。

Those energy shells correspond to periods in the periodic table.

那些级对应于元素表中。

Now how do you move an electron to a farther level?

现在你怎么把电子移到更远级？

The flexibility such frequency-hopping confers means particles with a range of energy levels can be targeted.

这种跳频赋予灵活性意味着可以瞄准具有一系列级粒子。

So if we had a lot of energy we could jump it up to this energy level.

所以如果我们有很多，我们就可以把它提升到这级。

This electron can have one energy level, or another, but not a value in  between those two.

该电子可以具有一级或另一级，但不是介于这两者之间值。

And things with higher density will absorb most of the low-energy X-rays, and allow some of the higher-energy rays to pass through.

而那些高密度东西则会吸收大部分低级X射线，允许高级射线穿过。

From a tiny sphere, to electron orbits, to energy levels and then to the electrons being wave-like charge distributions.

从一微小球体， 到电子轨道，再到级， 然后是电子呈现出波状电荷分布。

Or absorb a photon if it's going from, let's say the proton is spinning up.

或者吸收一光子，如果它是从低级跃迁到高级，比如说质子自旋向上。

Like, Bohr’s model can be helpful if you need to focus on energy levels and radiation.

比如说，玻尔模型在你需要关注级和辐射时会很有帮助。

And that means that the elements in that first period, that their electrons will fill the first energy shell.

这意味着第一元素，它们电子将填充第一级。

Well, it's in the first period, so it's going to go into the first energy shell.

好吧，它在第一，所以它会进入第一级壳层。

And so the first electron will go right here in the 1s energy shell.

那么第一电子将会进入1s级壳层。

If it gives off an equal photon it will drop down to a lower level.

如果它释放出一同等光子，它就会降到一更低级。

He's like, well, just like don't worry about it and just like calculate the hydrogen energy levels, right?

他说，好吧，别操心这了， 直接去计算氢级就行了，对吧？

If it goes from down to up, it absorbs a photon.

如果它从低级跃迁到高级，它就会吸收一光子。