"SDN:P07::67OPLRFZ" . "false" . . "2018-02-12 16:53:18.0" . "" . "The surface called \"surface\" means the lower boundary of the atmosphere. \"Content\" indicates a quantity per unit area. \"Radioactivity\" means the number of radioactive decays of a material per second. \"Cm\" means the element \"curium\" and \"248Cm\" is the isotope \"curium-248\" with a half-life of 1.72e+08 days."@en . "1" . "2018-02-12 16:53:18.0" . . "SDN:P07::67OPLRFZ" . "accepted"@en . "1" . . . . . "surface_radioactivity_content_of_248Cm"@en . "SDN:P07::67OPLRFZ" .