This article is about Aktinum. As of 2010, 31 actinium isotopes, eight excitement nuclear status and its nuclear species were recognized.Three of them, AC, AC, and AC were found in nature and the rest were made of artificial synthesis.Only three natural isotopes can be used to apply.Actinium-225 enters the radioactive nepunium.This was first discovered in 1947 when U collapsed.This was a α-radiator with a half-life of 10 days.The Actinum-225 is less than the Axinum-228, but the demand for radioactive tracers is promising.Actinium-227 (half-life: 21.77) exists in all uranium ores, but only a small amount exists.1 gram of uranium ore (when radioactive equilibrium) contains only 2 × 10^ gram of AC.Actinum-228 enters the radioactive thorium.It is produced by the collapse of the RA.This was a β radiator with a half -life of 6.15 hours. 1 ton of thorium contains 5 × 10^gram of AC.This was discovered by Ottohan in 1906.
Where does the Akinum-225 belong?
Radioactive Nepunium