Element Dubnium (Kurchatovium, Joliotium, Unnilpentium, Nielsbohrium, Hahnium), Db

Dubnium (named after Dubna, Russia) was first synthesized in 1967 at the Joint Institute for Nuclear Research in Dubna, Russia by Georgy Nikolaevich Flerov et al producing nuclide ²⁶¹Db by bombarding ²⁴³Am with ²²Ne.

In 1970 researchers led by Albert Ghiorso at the Berkeley Laboratory of the University of California by bombardment of californium with nitrogen ions and named Hahnium after Otto Hahn (symbol Ha). Also this element was named Nielsbohrium (symbol Ns) in honor of Niels Bohr, meanwhile systematic International Union of Pure and Applied Chemistry (IUPAC) name Unnilpentium (symbol Unp). Another IUPAC suggested name was Joliotium (symbol Jl). In 1997, at the final elements christening during the International Union of Pure and Applied Chemistry (IUPAC) Council meeting in Geneva, element 104 was named Dubnium and element 105 got the name and symbol Dubnium (symbol Db).