EUROPIUM radioactive — artificial radioisotope (nuclide) of a chemical element of the europium belonging to the III group of a periodic system of elements of D. I. Mendeleyev. Eu belongs to rare earth elements — to lanthanides (see); sequence number 63. In the nature europium exists in the form of mix of two stable isotopes — 151 Eu (47,86%) and 153 Eu (52,14%). More than 15 artificial radioisotopes (radionuclides) of europium from which only are received 152 Eu and 154 Eu found practical application in the industry as a source of gamma radiation for gamma-radiography of metal products. In a gamma therapy artificial radioisotopes of europium are not used since there are other radioisotopes analogs, cheaper, with more suitable radiation characteristics, in particular 60 Co and 137 Cs (see. Gamma therapy ; Cobalt, radioactive ; Caesium ). Isotope is of interest 155 Eu having a soft range of gamma radiation. This isotope can be used for medical gammagrafiya (see). See also Isotopes .
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