翻訳と辞書 Words near each other ・ Isotope dilution ・ Isotope effect ・ Isotope electrochemistry ・ Isotope fractionation ・ Isotope geochemistry ・ Isotope hydrology ・ Isotope lists ・ Isotope lists, 0-24 ・ Isotope lists, 25-48 ・ Isotope lists, 49-72 ・ Isotope lists, 73-96 ・ Isotope lists, 97+ ・ Isotope separation ・ Isotope-coded affinity tag ・ Isotope-ratio mass spectrometry ・ Isotopes of actinium ・ Isotopes of aluminium ・ Isotopes of americium ・ Isotopes of antimony ・ Isotopes of argon ・ Isotopes of arsenic ・ Isotopes of astatine ・ Isotopes of barium ・ Isotopes of berkelium ・ Isotopes of beryllium ・ Isotopes of bismuth ・ Isotopes of bohrium ・ Isotopes of boron ・ Isotopes of bromine ・ Isotopes of cadmium Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク Isotopes of actinium ： ウィキペディア英語版 Isotopes of actinium Actinium (Ac) has no stable isotopes and no characteristic terrestrial isotopic composition, thus a standard atomic mass cannot be given. There are 31 known isotopes, from 206Ac to 236Ac, and 2 isomers. Two isotopes are found in nature, 227Ac and 228Ac, as intermediate decay products of, respectively, 235U and 232Th. 228Ac is extremely rare, and almost all natural actinium is 227Ac. The most stable isotopes are 227Ac with a half-life of 21.772 years, 225Ac with a half-life of 10.0 days, and 226Ac with a half-life of 29.37 hours. All other isotopes have half-lives under 10 hours, and most under a minute. The shortest-lived known isotope is 217Ac with a half-life of 69 ns. Actinium also has two meta states. Purified 227Ac comes into equilibrium with its decay products (227Th and 223Fr) after 185 days.〔 〕 == Table == 〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Isotopes of actinium」の詳細全文を読む スポンサード リンク 翻訳と辞書 : 翻訳のためのインターネットリソース Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.