So what is the charge on a helium nucleus?
那么氦原子核的电荷量是多少呢？
We have a helium nucleus and one electron.
我们有一个氦核和一个电子。
And there he was able to identify the alpha particle as the helium nucleus.
他证实了，阿尔法粒子就是氦核。
The first type discovered -- alpha decay -- is when a radioactive particle emits a Helium nucleus !
我们发现的第一种衰变方式——阿尔法衰变——是放射性粒子产生氦分子！
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。
Because of this, the quality of helium-4 nucleus has been reduced.
正因为这样，氦4原子核的质量减少了。
Because of this, the quality of helium-4 nucleus has been reduced.
正因为这样，氦4原子核的质量减少了。
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