Neutrons and protons are bound together in the nucleus of 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》

So let's take two cases of shielding if we're talking about, for example, the helium, a helium nucleus or a helium atom.

所以我们来对屏蔽举两个例子，如果我们在讨论氦，举例来说一个氦原子核或者氦原子。

youdao

As such, it governs-among other things-the energy levels of an atom formed from negatively charged electrons and a positive nucleus.

就此而论，它控制由带负电荷的电子与正电荷原子核的形成的原子能级。

youdao

If dark matter particles exist, scientists say, they should be able to observe a small amount of light given off when they hit the nucleus of a xenon atom.

VOA: special.2009.07.21

Because what it tells is that we can figure out exactly what the radius of an electron and a nucleus are in a hydrogen atom.

我们可以,准确的算出,氢原子中,电子。

麻省理工公开课 - 化学原理课程节选

We're going to be looking at the solutions to the Schrodinger equation for a hydrogen atom, and specifically we'll be looking at the binding energy of the electron to the nucleus.

我们将研究下氢原子薛定谔方程的解,特别是电子和核子的结合能,我们将研究这部分。

麻省理工公开课 - 化学原理课程节选

Each fission reaction splits the nucleus of an atom of uranium-235 or plutonium-239 into two smaller atoms and releases a great deal of energy.

FORBES: Explainer: What Caused The Incident At Fukushima-Daiichi

The principle behind these experiments is that particles hitting the xenon cause the nucleus of the atom to give off a little bit of light.

CNN: How particle smasher and telescopes relate

Laser interferometers are looking for disturbances in their experimental set-ups that are equivalent to mere fractions of the diameter of a proton, one of the particles that make up the nucleus of an atom.

BBC: Lab tuned to gravity's 'ripples'