The heavy water-moderated molten salt reactor(HWMSR)is a newly proposed reactor concept,in which heavy water is adopted as the moderator and molten salt dissolved with fissile and fertile elements is used as the fuel....The heavy water-moderated molten salt reactor(HWMSR)is a newly proposed reactor concept,in which heavy water is adopted as the moderator and molten salt dissolved with fissile and fertile elements is used as the fuel.Issues arising from graphite in traditional molten salt reactors,including the positive temperature coefficient and management of highly radio-active spent graphite waste,can be addressed using the HWMSR.Until now,research on the HWMSR has been centered on the core design and nuclear fuel cycle to explore the viability of the HWMSR and its advantages in fuel utilization.However,the core safety of the HWMSR has not been extensively studied.Therefore,we evaluate typical accidents in a small modular HWMSR,including fuel salt inlet temperature overcooling and overheating accidents,fuel salt inlet flow rate decrease,heavy water inlet temperature overcooling accidents,and heavy water inlet mass flow rate decrease accidents,based on a neutronics and thermal-hydraulics coupled code.The results demonstrated that the core maintained safety during the investigated accidents.展开更多
In this study,we revisit the previous mass relations of mirror nuclei by considering 1/N-and 1/Z-dependent terms and the shell effect across a shell.The root-mean-squared deviation is 66 keV for 116 nuclei with neutro...In this study,we revisit the previous mass relations of mirror nuclei by considering 1/N-and 1/Z-dependent terms and the shell effect across a shell.The root-mean-squared deviation is 66 keV for 116 nuclei with neutron number N≥10,as com-pared with experimental data compiled in the AME2020 database.The predicted mass excesses of 173 proton-rich nuclei,including 98 unknown nuclei,are tabulated in the Supplemental Material herein with competitive accuracy.展开更多
Garvey-Kelson mass relations connect nuclear masses of neighboring nuclei within high accuracy, and provide us with convenient tools in predicting unknown masses by extrapolations from existent experimental data. In t...Garvey-Kelson mass relations connect nuclear masses of neighboring nuclei within high accuracy, and provide us with convenient tools in predicting unknown masses by extrapolations from existent experimental data. In this paper we investigate optimal"channels" of the Garvey-Kelson relations in extrapolation to the unknown regions, and tabulate our predicted masses by using these optimized channels of the Garvey-Kelson relations.展开更多
Systematic calculations of low-lying energy levels,B(E2)transitions,and g factors of even-even tellurium isotopes with mass numbers from 128 to 140 are performed via the nucleon-pair approximation(NPA)of the shell mod...Systematic calculations of low-lying energy levels,B(E2)transitions,and g factors of even-even tellurium isotopes with mass numbers from 128 to 140 are performed via the nucleon-pair approximation(NPA)of the shell model with phenomenological multipole-multipole interactions.An optimal agreement is obtained between the calculated results and experimental data.The yrast band structures of nuclei below and above the N=82 shell closure are compared and discussed.In particular,the evolutionary differences of B(E2;2^(+)_(1)→0^(+)_(1))values and g(2^(+)_(1))factors,with respect to the symmetry of N=82,are attributed to the dominant contribution differences in neutron and proton excitations,respectively.展开更多
基金the National Natural Science Foundation of China(No.11905285)the Shanghai Natural Science Foundation(No.20ZR1468700)the Youth Innovation Promotion Association CAS(No.2022258).
文摘The heavy water-moderated molten salt reactor(HWMSR)is a newly proposed reactor concept,in which heavy water is adopted as the moderator and molten salt dissolved with fissile and fertile elements is used as the fuel.Issues arising from graphite in traditional molten salt reactors,including the positive temperature coefficient and management of highly radio-active spent graphite waste,can be addressed using the HWMSR.Until now,research on the HWMSR has been centered on the core design and nuclear fuel cycle to explore the viability of the HWMSR and its advantages in fuel utilization.However,the core safety of the HWMSR has not been extensively studied.Therefore,we evaluate typical accidents in a small modular HWMSR,including fuel salt inlet temperature overcooling and overheating accidents,fuel salt inlet flow rate decrease,heavy water inlet temperature overcooling accidents,and heavy water inlet mass flow rate decrease accidents,based on a neutronics and thermal-hydraulics coupled code.The results demonstrated that the core maintained safety during the investigated accidents.
基金supported by the National Natural Science Foundation of China(No.11905130).
文摘In this study,we revisit the previous mass relations of mirror nuclei by considering 1/N-and 1/Z-dependent terms and the shell effect across a shell.The root-mean-squared deviation is 66 keV for 116 nuclei with neutron number N≥10,as com-pared with experimental data compiled in the AME2020 database.The predicted mass excesses of 173 proton-rich nuclei,including 98 unknown nuclei,are tabulated in the Supplemental Material herein with competitive accuracy.
基金supported by the National Natural Science Foundation of China(Grant Nos.11225524,11675101,and 11505113)the National Basic Research Program of China(Grant No.2013CB834401)+1 种基金Shanghai Key Laboratory(Grant No.11DZ2260700)the Program of Shanghai Academic/Technology Research Leader(Grant No.16XD1401600)
文摘Garvey-Kelson mass relations connect nuclear masses of neighboring nuclei within high accuracy, and provide us with convenient tools in predicting unknown masses by extrapolations from existent experimental data. In this paper we investigate optimal"channels" of the Garvey-Kelson relations in extrapolation to the unknown regions, and tabulate our predicted masses by using these optimized channels of the Garvey-Kelson relations.
基金Supported by National Natural Science Foundation of China (11875188, 11905130 and 12075169)Sichuan Science and Technology Program (2019JDRC0017)+1 种基金the Doctoral Program of Southwest University of Science and Technology (18zx7147)Shanghai Sailing Program (19YF1434200)。
文摘Systematic calculations of low-lying energy levels,B(E2)transitions,and g factors of even-even tellurium isotopes with mass numbers from 128 to 140 are performed via the nucleon-pair approximation(NPA)of the shell model with phenomenological multipole-multipole interactions.An optimal agreement is obtained between the calculated results and experimental data.The yrast band structures of nuclei below and above the N=82 shell closure are compared and discussed.In particular,the evolutionary differences of B(E2;2^(+)_(1)→0^(+)_(1))values and g(2^(+)_(1))factors,with respect to the symmetry of N=82,are attributed to the dominant contribution differences in neutron and proton excitations,respectively.