Abstract —The kinetics of Np(VI and V) reduction was studied in model underground water in the presence of bacteria, isolated from from deep-injection disposal of liquid radioactive wastes of Siberian Chemical Plant. Obtained data indicate a chemical instability of Np(VI) in the studied system. The reduction of neptunium (V) depended on its initial concentration and the presence of microorganisms. In microbiome samples, the reduction rate has significantly increased and neptunium-bearing particles more than 200 nm in size were formed. At neptunium concentrations less than 10 –7 М, the reduction rate constant did not depend on the radionuclide content (half-reaction period of 36–40 days). An increase of Np concentration to 10 –6 М led to a two-fold decrease of the reduction rate constant.

中文翻译：

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模型地下水中镎的生物转化

摘要 —研究了在细菌存在下模型地下水中 Np(VI 和 V) 还原的动力学，该细菌是从西伯利亚化工厂液体放射性废物的深层注入处理中分离出来的。获得的数据表明 Np(VI) 在研究系统中的化学不稳定性。镎 (V) 的减少取决于其初始浓度和微生物的存在。在微生物组样本中，减少率显着增加，并形成了超过 200 nm 的含镎颗粒。在镎浓度低于 10 –7 М 时，还原速率常数与放射性核素含量无关（36–40 天的半反应期）。Np 浓度增加到 10 –6 М 导致还原速率常数降低两倍。