食品中的放射性碘直接引起人们的关注，但是它的半衰期相对较短并将在短时间内自然衰变。
Radioactive iodine in food is of immediate concern, but it has a relatively short half-life and will naturally decay over a short time frame.
半衰期实际上是,一半反应物消失的时间。
So, the half-life is just the time that it takes for half of the reactants to disappear.
但碘- 131则不同，它的半衰期是八天，意味着它需要数月时间才会完全消失。
However, iodine-131 has a short half-life of eight days, which means it will decay away completely in the environment in a matter of months.
应用推荐