But it left behind a slurry of other elements, including types of radioactive strontium, caesium, and technetium.

但它留下了其他元素，包括放射性锶、铯和锝。

Well we are going to try and refreeze the caesium by cooling it with liquid nitrogen.

好吧， 我们将尝试通过用液氮冷却铯来重新冻结铯。

Both the strontium and caesium emit high levels of beta rays, a kind of ionizing radiation, as well as a lot of heat.

锶和铯都会发出大量的β射线（一种电离辐射）和热量。