"false" . "1" . . "SDN:P07::05T0D2U6" . "\"Radioactivity\" means the number of radioactive decays of a material per second. \"Radioactivity concentration\" means radioactivity per unit volume of the medium. \"Pr\" means the element \"praseodymium\" and \"144Pr\" is the isotope \"praseodymium-144\" with a half-life of 1.20e-02 days."@en . "SDN:P07::05T0D2U6" . "SDN:P07::05T0D2U6" . . "radioactivity_concentration_of_144Pr_in_air"@en . . "" . "1" . . . "2018-02-12 16:53:18.0" . "accepted"@en . "2018-02-12 16:53:18.0" . .