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mesothoriumenUK
mes·o·tho·ri·um M0239500 (mĕz′ə-thôr′ē-əm, mĕs′-)n. Either of two decay products of thorium, mesothorium I, an isotope of radium, or mesothorium II, an isotope of actinium.mesothorium (ˌmɛsəʊˈθɔːrɪəm) n (General Physics) physics obsolete either of the two radioactive elements which are decay products of thorium. Mesothorium I is now called radium-228. Mesothorium II is now called actinium-228mesothoriumenUK
mes·o·tho·ri·um (mez'ō-thōr'ē-ŭm), The first two disintegration products of thorium; mesothorium 1 is 228Ra, a beta emitter with a half-life of 6.7 years, decaying into mesothorium 2, which is 228Ac, a beta emitter with a half-life of 6.13 hr, which disintegrates to radiothorium (228Th). |