… Radioactive chemical elements and radioactive isotopes (including the fissile or fertile …
Explanatory notes
… 28.44 ‑ Radioactive chemical elements and radioactive isotopes … gadolinium-148, polonium-208, polonium-209, polonium-210, radium-223, uranium-230 or uranium-232, and their compounds; … which are all called uranium, but their mass number ranges from 227 to 240; they are designated, for example, as …