135Cs是一长寿命裂变产物核素,为了准确测定其热中子反应截面,必须从裂变产物中分离、提取放化纯的135Cs。由于分离的135Cs是供其热中子反应截面测量用的,除了考虑放射性核素的去污外,还要求在分离时不能引入其它可活化的基体。因此,离子交换法被认为是比较好的分离方法。在离 135Cs is a long-lived fission product nuclide. In order to accurately determine its thermal neutron cross-section, 135Cs must be separated and extracted from the fission products. Since the separated 135Cs are used for the measurement of their thermal neutron cross sections, it is required that other activatable substrates should not be introduced at the time of separation in addition to the decontamination of radionuclides. Therefore, ion exchange method is considered as a better separation method. Away from