Investigations in the field of radiochemistry

The review of the major results in the field of radiochemistry, obtained for the last 15-20 years, is given. One of the directions of the investigations is chemical preparation and study of uranium and transuranium elements properties in extraordinary degrees of oxidation. The effect of the hard oxidants or reducers in the strong complexing media is used in this case. The heptavalent form of neptunium and plutonium is discovered. Am(7) is prepared in the NaOH cooled solutions by the action of ozone and ion-radical O-, radiolitically generated. The attempt to prepare curium of the highest valency is made. The preparation of the large number of the technetium compounds in the oxidation degrees +7, +6, +5, +4 as well as clusters with multiple bond Tc-Tc is described. The investigations in the chemistry of promethium and protactinium are started. The methods of Pa separation from wastes of uranium production and thorium irradiated by neutrons are developed. The methods of separation and decontamination of radioactive fragment and transplutonium elements are developed. The use of the radioactive indicators is described