. "1" . "SDN:P07::375EQNVW" . "false" . . "SDN:P07::375EQNVW" . "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. \"Kr\" means the element \"krypton\" and \"83mKr\" is the metastable state of the isotope \"krypton-83\" with a half-life of 7.71e-02 days."@en . . . "2018-02-12 16:53:18.0" . "1" . "" . "accepted"@en . . . "SDN:P07::375EQNVW" . "2018-02-12 16:53:18.0" . "surface_radioactivity_content_of_83mKr"@en .