"" . "accepted"@en . "2018-02-12 16:53:18.0" . "1" . . "SDN:P07::5VM2D78P" . . "SDN:P07::5VM2D78P" . . "1" . . . "false" . "surface_radioactivity_content_of_250Bk"@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. \"Bk\" means the element \"berkelium\" and \"250Bk\" is the isotope \"berkelium-250\" with a half-life of 1.34e-01 days."@en . "2018-02-12 16:53:18.0" . . "SDN:P07::5VM2D78P" .