电沉积法制备226Ra α样品源的优化研究

α能谱法是一种直接测量α衰变的方法，具有探测限低、分析时间相对较短等优点。电沉积法制备的α样品源均匀且厚度可忽略，是目前最理想的制备²²⁶Ra的α样品源的方法。为制得较高电沉积率的²²⁶Ra的α样品源，本文对草酸氨/盐酸电沉积液中氯铂酸用量、电流密度、电沉积时间、草酸氨溶液的初始pH值和浓度等条件对²²⁶Ra电沉积率的影响进行了优化研究。结果表明，在氯铂酸用量为700 μg、电流密度为0.225 A/cm²、电沉积时间为60 min、草酸氨溶液浓度为0.05~0.13 mol/L、草酸氨溶液的初始pH值为1.0~2.5等电沉积条件下，²²⁶Ra电沉积样品源的电沉积率大于95%。

Optimization for Preparation of Plating226Ra for α Spectrometry

α spectrometry is a direct method to measure α-emitting radionuclides, which has the advantages of low detection limit and short time-consuming. The electrodeposition method is the most ideal technique for preparation of source for α spectrometry, by which the source is homogeneous and self-absorbance negligible. To obtain high quality of electrodeposition sample of²²⁶Ra, the effects of the quality of chloroplatinic acid, current density, electrodeposition time, initial pH and concentration of ammonia oxalate on electrodeposition yield of²²⁶Ra were investigated on the base of the ammonia oxalate/hydrochloric acid electrolytes. The results show that under the conditions of chloroplatinic acid doseage of 700 μg, the current density of 0.225 A/cm², the electrodeposition time of 60 min, the concentration of ammonia oxalate of 0.05-0.13 mol/L, the initial pH of ammonia oxalate of 1.0-2.5, the electrodeposition yield of²²⁶Ra is over 95%.