Discovery of a New Mendelevium Isotope

Abstract

Helium ion bombardments of E 2 53 have resulted 1r1 the identification of a new isotope of mendelevium (element 101) '<11th mass number 255. The isotope decays by orbital electron capture to Pm 2 55, with a bal.t' life of approximately

Separation and Purification of Berkelium-249 and Einsteinium-254

“…Because of its limited availability and shorter isotopic half-lives, einsteinium does not have many applications other than for basic research purposes and production of other heavy transuranic elements. However, in 1955, the element mendelevium was synthesized by bombarding 253 Es with helium ions [5]. Other applications include in-beam fission studies using 254 Es with the Tandem accelerator at the Japan Atomic Energy Agency and einsteinium characterization by Florida State University.…”

Discovery of isotopes of elements with

“…The discovery of mendelevium was officially accepted by the IUPAC-IUPAP Transfermium Working Group in 1993: "Element 101 was discovered by the Berkeley group -with certainty in 1958 [44] following strong indications in 1955 [43]" [11,45]. IUPAC adopted the name mendelevium but changed the symbol from "Mv" to "Md" at the 19 th IUPAC Conference in Paris 1957 [23,24].…”

Discovery of isotopes with Z≤10

“…"By an (α,n) reaction on 99 253 we have produced the isotope 101 256 which decays by electron capture with a half-life of the order of a half hour to 100 256 ; this isotope then decays by spontaneous fission with a half-life of the order of 3 to 4 hours." The half-life was later revised to 1.5 h [44]. [50].…”