Neutrons and protons are bound together in the nucleusof an atom.
在一个原子的核内，中子和质子聚合在一起。
《柯林斯英汉双解大词典》
2
The internal circles of the Atom mirror the cosmos, at once a law-abiding nucleusof energy, and at the same time the concentric heavenly spheres spinning in the galaxy.
原子的内部轨道是宇宙的真实镜像，一边是遵守规则的能量核，另一边是在星系中旋转的同心球体。
3
As such, it governs-among other things-the energy levels of an atom formed from negatively charged electrons and a positive nucleus.