Although almost all this material, which has a 24,000-year half-life, has since disappeared (primarily through natural radioactive decay), some of the plutonium itself underwent fission, as attested by the presence of its characteristic fission products.
Although almost all this material, which has a 24,000-year half-life, has since disappeared (primarily through natural radioactive decay), some of the plutonium itself underwent fission, as attested by the presence of its characteristic fission products.
这些物质半衰期为2万4000年，几乎已经全部消失（主要是经由自然的放射衰变过程），而且部份的钸本身又经过核分裂，这可由其核分裂产物为证。