【摘要】 本文以氮分子激光器为激发光源,研究了激发态铀酰离子在高氯酸溶液中的发光衰减和时间分辨发光光谱.铀酰离子的发光衰减与铀浓度以及溶液的pH有关,当铀浓度c_u<10^-3mol·dm^-3时,溶液pH为1.5～4.0范围内,发光呈单一指数衰减;当c_u≥10^-3mol·dm^-3时,发现发光呈双指数衰减,即除了上述发光组份外,还观察到另一发光寿命较长的组份.用时间分辨方法测得的铀酰溶液的发光光谱表明,上述现象与激发态水合铀酰离子及其水解产物形成的发光体有关.更多还原

【Abstract】 The luminescence decay and time-resolved luminescence spectra of the excited uranys ion in perchloric acid solution have been studied with a pulsed nitrogen laser and boxcar integrated averager. The luminescence decay depends on the concentration of U（Ⅵ） an l the pH of the aqueous solution. While the U（Ⅵ） concentration is less than 10^-3 mol·dm^-3, the luminescence decay is single exponential from pH 1.5 to 4.0. The lifetime i about 2.5 μs and no pH effect was observed. While the U（Ⅵ） concentration is higher than 10^-3mol·dm^-3, the luminescence undergoes biexponential decay, and a longer lifetime component was also found. Time-resolved spectra with delay time of 0.5 and 20μs reveal that the biexponential decay could be interpreted in terms of the deactivation of the excited uranyl aquo-ion and hydrolysis product of U （Ⅵ）.更多还原