An unstable radioactive nucleus can become stable by emitting particles and energy - a process called " decay " 一颗不稳定即具有放射性的原子核在放射出粒子及能量后可变得较为稳定,这个过程称为衰变。
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An unstable ( radioactive ) nucleus can become stable by emitting particles and energy - a process called " decay " 一颗不稳定(即具有放射性)的原子核在放射出粒子及能量后可变得较为稳定,这个过程称为衰变。