分类: 核科学技术 >> 裂变堆工程技术 提交时间: 2023-06-18 合作期刊: 《Nuclear Science and Techniques》
摘要: Probabilistic safety assessment (PSA) is important in nuclear safety review and analysis. Because the design and physics of the fluoride salt-cooled high temperature reactor (FHR) differ greatly from the pressurized water reactor (PWR), the methods and steps of PSA in FHR should be studied. The high-temperature gas-cooled reactor (HTR-PM) and sodium-cooled fast reactors have built the PSA framework, and the framework to finish the PSA analysis. The FHR is compared with the PWR, HTR-PM and sodium-cooled fast reactors from the physics, design and safety. The PSA framework of FHR is discussed. In the FHR, the fuel and coolant combination provides large thermal margins to fuel damage (hundreds of degrees centigrade). The tristructural-isotropic (TRISO) as the fuel is independent in FHR core and its failure is limited for the core. The core damage in Level 1 PSA is of lower frequency. Levels 1 and 2 PSA are combined in the FHR PSA analysis. The initiating events analysis is the beginning, and the source term analysis and the release types are the target. Finally, Level 3 PSA is done.
分类: 物理学 >> 核物理学 提交时间: 2023-06-18 合作期刊: 《Nuclear Science and Techniques》
摘要: In radiotherapy, the energy of the rays used could be larger than 10 MeV, which would potentially activate stable nucleus into a radioactive one. The induced reactions on some of the human essential elements are studied to show the probability of changes of nuclei. The Talys1.4 toolkit was adopted as the theoretical model for calculation. The reactions investigated include the (, n) and (, p) channels for the stable Na, Mg, Cl, K, Ca, and Fe isotopes, with the incident energy of ranging from 1 to 30 MeV. It was found that the cross sections for the reactions are very low, and the maximum cross section is no larger than 100 mb. By considering the threshold energy of the channel, the half-life time of the residue nucleus, and the percentage of the element accounting for the weight and its importance in the body, it is suggested to track the radioactive nuclei 22Na, 41Ca, and 42,43K after therapy. The results might be useful for medical diagnosis and disease treatment.