radioactive decay (redirected from Activity (radioactivity))

radioactive decay,

the disintegration of the nucleus of an unstable nuclide by the spontaneous emission of charged particles, photons, or both.

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decay,

v to decompose.

decay, dental,

n See caries.

decay product,

n See daughter.

decay, radioactive,

n the disintegration of the nucleus of an unstable nuclide by the spontaneous emission of charged particles and/or photons.

decay, senile,

n See caries, senile dental.

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radioactive

characterized by radioactivity.

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radioactive decay

spontaneous decomposition of the nuclei of the atoms of radioactive substances. Measured as the proportion of the atoms in a radionuclide that decompose per unit of time, usually stated as the half-life of that particular isotope.

radioactive fallout

dissemination of radioactive substances through the atmosphere and deposition on the environment generally; causes radiation injury.

radioactive isotope

radionuclide. A radioactive nuclide, e.g. radioactive iodine or strontium.

radioactive tracer

see radioactive tracer.