"2018-02-12 16:53:18.0" . . "surface_radioactivity_content_of_138Xe"@en . . . "1" . "SDN:P07::1VVUYJ1Q" . "2018-02-12 16:53:18.0" . . "" . "SDN:P07::1VVUYJ1Q" . "1" . "accepted"@en . . . "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. \"Xe\" means the element \"xenon\" and \"138Xe\" is the isotope \"xenon-138\" with a half-life of 9.84e-03 days."@en . "false" . "SDN:P07::1VVUYJ1Q" .