This fallout material decays over a long period of time, and is the main source of residual nuclear radiation.

尘降物需要很长的时间才会衰减，这是核辐射残留的主要来源。

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This fallout material decays over a long period of time, and is the main source of residual nuclear radiation.

尘降物需要很长的时间才会衰减，这是核辐射残留的主要来源。

youdao