who conducted the experiment of hydrogen emission spectrum in a magnetic field.

塞曼做了一个,磁场中的氢原子光谱实验。

麻省理工公开课 - 固态化学导论课程节选

So, let's say we're looking at an element and we have an emission spectra, and we know that it has five distinct different kinetic energies in that spectrum.

比如我们正在研究一个元素,而且我们得到了它的光谱，知道了在它的光谱里,有五个分立的动能。

麻省理工公开课 - 化学原理课程节选