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actinium series

noun, Chemistry
the radioactive series that starts with uranium 235 and ends with a stable isotope of lead of mass number 207.
Origin of actinium series
1955-60 Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for actinium series
  • These are the uranium series, the thorium series, and the actinium series.
  • The majority of these can be grouped into the uranium series, the actinium series, and the thorium series.
British Dictionary definitions for actinium series

actinium series

a radioactive decay series that starts with uranium-235 and ends with lead-207
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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