高水平放射性废物的安全处理和处置是世界上许多国家正面临的集政治、经济、科技、环境保护以及核能可持续发展为一体的重大难题之一。本项目旨在分子水平上研究易迁移的裂变产物放射性铯(如Cs-137、Cs-135和Cs-134)在处置库天然屏障花岗岩中的微观吸附机理。拟采用批式实验法、电子探针分析(EPMA)、以及基于同步辐射技术的扩展边X-射线吸收精细结构分析(EXAFS)和X-射线荧光光谱(µ-XRF)等技术阐明放射性铯与北山花岗岩相互作用过程；重点考察环境因素与铯在花岗岩中吸附形态之间的关联，进而揭示铯的微观吸附形态与其在花岗岩中的迁移/滞留的关系。构建可量化计算和准确预测放射性铯在北山花岗岩中地球化学行为的模型，可为我国核裂变能的可持续发展及环境保护提供重要的基础理论和科学决策依据

Nowadays, the whole world has paid more attention to the deep geological disposal, which is a temporarily safety method to avoid the high level radioactive waste (HLRW) releasing to biosphere environment. Thereby migration behaviors of radionuclides become the prior consideration factor in the performance evaluation and safety assessment of the repository. In this proposal, the adsorption and desorption of key fission product radiocesium (RCs) including Cs-137, Cs-135 and Cs-134 in natural barrier, i.e., granite were studied at macro- and micro-scales using batch and spectroscopies such as extended X-ray absorption fine structure (EXAFS) and electron probe micro-analyzer (EPMA), etc. The relationship between environmental factors and adsorption species of RCs on granite will be demonstrated. Moreover, a quantitative model based on thermodynamic would be constructed to predict the geochemical behaviors of RCs in granite. The results will be expected to illustrate the sorption/desorption mechanism of RCs on granite at different conditions, which is also of very importance to the evaluation of performance and safety of Chinese geological repository for HLRW as well as environmental protection.