Mendelevium

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Mendelevium, symbol Md, artificially created radioactive element with an atomic number of 101. Mendelevium is one of the transuranium elements in the actinide series of the periodic table. Named for the Russian chemist Dmitry Mendeleyev, mendelevium-256 was discovered in 1955 at the University of California, Berkeley; it was produced by bombarding einsteinium-253 with alpha particles accelerated in a cyclotron (see Particle Accelerators). The isotope produced had a half-life of about 1.3 hours. The most stable isotope, mendelevium-258, has a half-life of 54 days. See also Radioactivity.

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