"SDN:P07::2AI7HE2F" . . "surface_radioactivity_content_of_207mPb"@en . . . . "1" . "1" . "SDN:P07::2AI7HE2F" . "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. \"Pb\" means the element \"lead\" and \"207mPb\" is the metastable state of the isotope \"lead-207\" with a half-life of 9.26e-06 days."@en . . "" . "accepted"@en . "SDN:P07::2AI7HE2F" . "2018-02-12 16:53:18.0" . "false" .