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mean life |
Also found in: Acronyms, Wikipedia, Hutchinson | 0.04 sec. |
mean lifeIn radioactivity, the average lifetime of all the nuclei of a particular unstable atomic species. This time interval is the sum of the lifetimes of all the individual unstable nuclei in a sample, divided by the total number of unstable nuclei present. It is the reciprocal of the decay constant. For a given isotope, the mean life is always 1.443 times its half-life. For example, lead-209 decays to bismuth-209 with a half-life of 3.25 hours and a mean life of 4.69 hours. mean life [′mēn ′līf] (physics) The average time during which a system, such as an atom, nucleus, or elementary particle, exists in a specified form; for a radionuclide or an excited state of an atom or nucleus, it is the reciprocal of the decay constant. Also known as average life; lifetime. How to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit webmaster's page for free fun content. |
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We calculated the mean lifetime asthma prevalence rate for the eight states in the study area from each state-level prevalence rate. The precise measurement of the mean lifetime [[tau]. The distribution's mean lifetime is 75 months and its median is 73 months. |
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