2844 42-- Actinium-225, actinium-227, californium-253, curium-240, curium- 241, curium-242, curium-243, curium-244, einsteinium-253, einsteinium-254, gadolinium-148, polonium-208, polonium-209, polonium-210, radium-223, uranium-230 ou uranium-232, et leurs composés; alliages, dispersions (y compris les cermets), produits céramiques et mélanges renfermant ces éléments ou composés