来自《耶鲁大学开放课程：生物医学工程探索第21集第21集》

you've probably heard of NMR, nuclear magnetic resonance.

可能会听说过NMR 即核磁共振
It was discovered by chemists as a way of

化学家发明了这种方法
analyzing chemical samples.

用来分析化学物质
It turns out that if you put certain nuclei,

研究表明如果你将某些核子
if you put certain atoms in a magnetic field,

将某些原子放到磁场中
some of them will align with the magnetic field

它们会在磁场中有序排列
because they have a magnetic dipole;

因为它们具有磁偶极子
atoms have a magnetic dipole.

原子具有磁偶极子
Hydrogen atoms or protons have an odd number of nuclei,

氢原子或者质子有奇数个核子
of neutrons or protons.

奇数个中子或者质子
Because of that they have a dipole, a magnetic dipole.

因此它们具有偶极即磁偶极
You put them in a magnetic field,

将它们放在磁场中