Investigation of alpha-irradiation effect on valent state of actinides

A study was made on radiation-chemical behaviour of americium (5) ions in nitric acid solutions in wide range of change of medium content and dose rate of internal α-irradiation (244Cm) solution. Radiation-chemical behaviour of americium (5) ions was investigated at 5x10-3-6.5 W/l dose rate, 0.01-8.6 mol/l nitric acid consentration, 0-9 mol/l lithium nitrate concentration and 1.1-6.3 mmol/l initial americium (5) concentration. Americium (5) is transformed only into americium (3) under mentioned conditions. Formation of americium (6) in noticeable amounts (> 0.05 mmol/l) wasn't observed even at high values of HNO3 and Am (5) concentrations and low values of dose rate. The law of the rate of americium (5) reduction was established. It was assumed that the rate of americium (5) reduction is affected by nitrite ion - the main product of nitrate-ion α-radiolysis