I would appreciate receiving any information (published or unpublished) on alpha and beta emitters with half lives greater than 4 years that are used in paints primarily for the purpose of fluorescence. Thank you, Nisy Elizabeth Ipe, Ph.D., C.H.P. Consultant, Shielding Design, Dosimetry & Radiation Protection Email:nisy@comcast.net "Doing the right thing, doing it right"