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Related to cobalt-57: Cobalt-60, cobalt 58


A radioactive isotope of cobalt with a half-life of 272 days.


a chemical element, atomic number 27, atomic weight 58.933, symbol Co. A component of vitamin B12. See Table 6.

a radioisotope of cobalt having a half-life of 270 days; used as a label for cyanocobalamin. Symbol 57Co.
a radioisotope of cobalt having a half-life of 5.27 years and a principal gamma ray energy of 1.33 MeV; used as a radiation therapy source. Symbol 60Co.
cobalt nutritional deficiency
causes anorexia and poor weight gain. Identification of the disease is based on chemical analysis of pasture and soil and biochemical analysis of animal tissues and fluids. Called also enzootic marasmus, Grand Traverse disease and other regional names.
cobalt poisoning
accidental overdosing with cobalt causes listlessness, weight loss and incoordination.
References in periodicals archive ?
In 1991, after most of the cobalt-57 had decayed, titanium-44 assumed the role of the dominant source of energy.
The flatter curve matches the slower decay of another isotope, cobalt-57, which the supernova produced in smaller amounts, the group notes.
One way to explain the greater emissions, note Suntzeff and his colleagues, is to assume that the supernova produced a ratio of cobalt-57 to cobalt-56 five times the ratio typical in our solar system.