Secondly, the act of splitting atoms released two more neutrons.

其次，原子分裂又释放出两个中子。

And as these various nuclei break down they release more neutrons and more unstable products and the process continues for a long time.

随着这些不同的原子核分解，它们释放出更多的中子和更不稳定的产物，并且这个过程会持续很长时间。