在树叶凋落之前，树会分解叶绿素分子，把有用的氮运回树枝中。

Before letting its leaves go, the tree dismantles their chlorophyll molecules and ships their valuable nitrogen back into the twigs.

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它最终被证明是，如果我有分子振动，你们知道，空气中有氮和氧。

It turns out that - if I've got molecular vibrations you know, there's nitrogen and oxygen in the air.

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腺嘌呤指分子的一部分，即含氮碱基。

Adenine refers to a portion of the molecule, the nitrogenous base.

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So what we can actually directly compare is the dissociation energy or the bond strength of nitrogen versus hydrogen.

因此实际上我们可以直接进行比较,对氮分子与氢分子的离解能,或键的强度。

麻省理工公开课 - 化学原理课程节选

So, for example, down here I wrote that it was n 2 and that it was h 2, but when I re-wrote the molecules up here, you saw that it's an h h single bond where it's a nitrogen-nitrogen triple bond.

比如，在这下面我写的是氮分子2,而这个是氢分子，但我在上面把这些分子的形式改写了，大家可以看到,这是一个氢与氢之间的单键，含一个氮与氮之间的三键。

麻省理工公开课 - 化学原理课程节选

Here is the atomic nitrogen, here is the atomic nitrogen and these are the orbitals of molecular nitrogen.

这是氮原子，这是氮原子,然后这是氮气的分子轨道。

麻省理工公开课 - 固态化学导论课程节选