radioactive isotope

radioactive isotope

n.

An isotope having an unstable nucleus that decomposes spontaneously by emission of a nuclear electron or helium nucleus and radiation, thus achieving a stable nuclear composition.

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Radioactive isotope

One of two or more atoms with the same number of protons but a different number of neutrons with a nuclear composition. In nuclear scanning, radioactive isotopes are used as a diagnostic agent.

Mentioned in: Multiple-Gated Acquisition (MUGA) Scan, Technetium Heart Scan

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radioactive isotope,

n See radioisotope.

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isotope

a chemical element having the same atomic number as another (i.e. the same number of nuclear protons), but having a different atomic mass (i.e. a different number of nuclear neutrons).

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radioactive isotope

one having an unstable nucleus and which emits characteristic radiation during its decay to a stable form. See also radioisotope.

stable isotope

one that does not transmute into another element with emission of corpuscular or electromagnetic radiations.

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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.

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radioactive isotope

Radionuclide, see there