ler ov ▁and ▁began ▁working ▁at ▁the ▁J oint ▁Institute ▁for ▁N uc lear ▁Research ▁( J IN R ) ▁in ▁Dub na , ▁near ▁Moscow . ▁ ▁He ▁became ▁director ▁of ▁the ▁F ler ov ▁Labor atory ▁of ▁N uc lear ▁Re actions ▁at ▁J IN R ▁in ▁ 1 9 8 9 , ▁after ▁F ler ov ▁retired , ▁and ▁remained ▁in ▁the ▁position ▁until ▁ 1 9 9 6 , ▁when ▁he ▁was ▁named ▁the ▁scientific ▁leader ▁of ▁the ▁F ler ov . ▁ ▁Disc overy ▁of ▁super - he avy ▁chemical ▁elements ▁In ▁the ▁ 1 9 7 0 s , ▁O gan ess ian ▁invent ed ▁the ▁method ▁of ▁cold ▁fusion , ▁a ▁technique ▁to ▁produce ▁trans act in ide ▁elements ▁( super he avy ▁elements ). ▁It ▁played ▁a ▁vital ▁role ▁in ▁the ▁discover ies ▁of ▁elements ▁from ▁ 1 0 6 ▁to ▁ 1 1 3 . ▁From ▁the ▁mid - 1 9 7 0 s ▁to ▁the ▁mid - 1 9 9 0 s , ▁the ▁partners hip ▁of ▁J IN R , ▁led ▁by ▁O gan ess ian , ▁and ▁the ▁G SI ▁Hel m hol tz ▁Centre ▁for ▁He avy ▁I on ▁Research ▁in ▁Germany , ▁led ▁to ▁the ▁discovery ▁of ▁six ▁chemical ▁elements ▁( 1 0 7 ▁to ▁ 1 1 2 ): ▁bo h rium , ▁me it ner ium , ▁h ass ium , ▁d arm stadt ium , ▁ro ent gen ium , ▁and ▁cop ern ici um .