In the event of a severe nuclear accident, one major concern is the release of radioactive material into the environment causing potential exposure of the general public to radiation. Among the volatile radionuclides are a range of tellurium isotopes. Due to the radioactivity and the volatility of tellurium, it has to be taken into account when assessing the overall effects of an accident. The interest in tellurium is not limited only to its release but also to the fact that some tellurium isotopes decay to iodine, and thus affect the iodine release behavior. The release and transport behavior of tellurium has been investigated over the past decades, however, the aqueous chemistry of tellurium in the complex containment sump system is still unclear. This study presents the behavior of tellurium dioxide in simplified containment sump conditions in relation to dissolution, redox reactions, and interactions with water radiolysis products. The results indicate that radiolysis products have a significant effect on tellurium chemistry in both a reducing and oxidizing manner depending on the solution composition. The redox reactions also affect the solubility of tellurium. The results show that the current information used to assess tellurium source term needs to be reevaluated for both severe accident management and for code validation purposes.

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密封槽中的碲行为：溶解、氧化还原和辐射分解效应

在发生严重核事故时，一个主要问题是放射性物质释放到环境中，导致公众可能受到辐射照射。挥发性放射性核素中有一系列碲同位素。由于碲的放射性和挥发性，在评估事故的整体影响时必须将其考虑在内。对碲的兴趣不仅限于它的释放，还包括一些碲同位素衰变成碘，从而影响碘释放行为的事实。碲的释放和运输行为已在过去几十年中得到研究，然而，碲在复杂的安全壳系统中的水性化学仍不清楚。本研究展示了二氧化碲在简化的安全壳槽条件下与溶解、氧化还原反应以及与水辐解产物相互作用的行为。结果表明，辐射分解产物对碲化学具有显着影响，这两种方式取决于溶液组成。氧化还原反应也影响碲的溶解度。结果表明，用于评估碲源项的当前信息需要重新评估，以用于严重事故管理和代码验证目的。结果表明，辐射分解产物对碲化学具有显着影响，这两种方式取决于溶液组成。氧化还原反应也影响碲的溶解度。结果表明，用于评估碲源项的当前信息需要重新评估，以用于严重事故管理和代码验证目的。结果表明，辐射分解产物对碲化学具有显着影响，这两种方式取决于溶液组成。氧化还原反应也影响碲的溶解度。结果表明，用于评估碲源项的当前信息需要重新评估，以用于严重事故管理和代码验证目的。