"1" . "1" . . "" . "accepted"@en . . "2018-02-12 16:53:18.0" . . "SDN:P07::9NLB8450" . "false" . "2018-02-12 16:53:18.0" . "SDN:P07::9NLB8450" . . "SDN:P07::9NLB8450" . "surface_radioactivity_content_of_208Tl"@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. \"Tl\" means the element \"thallium\" and \"208Tl\" is the isotope \"thallium-208\" with a half-life of 2.15e-03 days."@en . .