n. Symbol Fl An artificially produced radioactive element with atomic number 114 that has only been produced in trace amounts and has five observed isotopes with mass numbers ranging from 285 to 289. Its most stable isotope has a half-life of about 2.7 seconds. See Periodic Table. [After the Flerov Laboratory of Nuclear Reactions at the Joint Institute for Nuclear Research located in Dubna, Russia, which collaborated in its discovery.] |
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