Graphite is applied to many applications in the field of atomic energy. In the design of nuclear reactors, such as ADS, HTGRs and fusion reactors, graphite is among the primary candidate materials for a reflector zone...Graphite is applied to many applications in the field of atomic energy. In the design of nuclear reactors, such as ADS, HTGRs and fusion reactors, graphite is among the primary candidate materials for a reflector zone to soften the neutron spectrum. Moreover, the accurate prediction of tritium breeding ratio and nuclear heating rate sets the necessity of using adequate nuclear data for carbon since they have strong influence on the feasibility of the overall design of fusion reactors.展开更多
The Accelerator-Driven Systems (ADS) is mainly used for nuclear transmutation of long-lived fission products, fuel breeding and energy production. China has started to develop the ADS project and is now underway vigor...The Accelerator-Driven Systems (ADS) is mainly used for nuclear transmutation of long-lived fission products, fuel breeding and energy production. China has started to develop the ADS project and is now underway vigorously.The combination of nuclear data with a Monte Carlo transportation code like MCNP-4C is widely applied to design such kind of nuclear engineering facilities. The integral experiment is conducted to benchmark the nuclear data, involved in design calculations, both with regard to the activation and the particle transport behavior.展开更多
The symmetry energy at the time of the production of intermediate mass fragments(IMFs) is studied using experimentally observed IMF multiplicities combined with quantum statistical model calculations(QSM of Hahn and S...The symmetry energy at the time of the production of intermediate mass fragments(IMFs) is studied using experimentally observed IMF multiplicities combined with quantum statistical model calculations(QSM of Hahn and St cker).The ratios of difference in chemical potentials between neutrons and protons relative to the temperature,(μn-μp)/T,and the double ratio temperature,T,were extracted experimentally in the reactions of64,70Zn,64Ni+58,64Ni,112,124Sn,197Au,232Th at 40A MeV.The extracted(μn-μp)/TTscales linearly with δNN,where δNN is the asymmetry parameter,(N-Z)/A,of the emitting source and(μn-μp)/T=(11.1 1.4)δNN0.21 was derived.The experimentally extracted(μn-μp)/T and the double ratio temperatures are compared with those from the QSM calculations.The temperatures-,T,and densities,ρ,extracted from the(μn-μp)/T values agreed with those from the double ratio thermometer which used the yield ratios of d,t,h and α particles.However the two analyses of the differential chemical potential analysis and the initial temperature analysis end up almost identical relation between T and ρ.T=5.25±0.75 MeV is evaluated from the(μn-μp)/Tanalysis,but no density determination was possible.From the extracted T value,the symmetry energy coefficient Esym =14.6±3.5 MeV is determined for the emitting source of T=5.25±0.75 MeV.展开更多
文摘Graphite is applied to many applications in the field of atomic energy. In the design of nuclear reactors, such as ADS, HTGRs and fusion reactors, graphite is among the primary candidate materials for a reflector zone to soften the neutron spectrum. Moreover, the accurate prediction of tritium breeding ratio and nuclear heating rate sets the necessity of using adequate nuclear data for carbon since they have strong influence on the feasibility of the overall design of fusion reactors.
文摘The Accelerator-Driven Systems (ADS) is mainly used for nuclear transmutation of long-lived fission products, fuel breeding and energy production. China has started to develop the ADS project and is now underway vigorously.The combination of nuclear data with a Monte Carlo transportation code like MCNP-4C is widely applied to design such kind of nuclear engineering facilities. The integral experiment is conducted to benchmark the nuclear data, involved in design calculations, both with regard to the activation and the particle transport behavior.
基金Supported by National Natural Science Foundation of China(NSFC) Projects (No.11075189)"100 Persons Project(Nos.0910020BR0 and Y010110BR0)"+2 种基金"ADS project 302"of the Chinese Academy of Sciences(No.Y103010ADS)supported by U.S.Department of Energy(Grant No.DE-FG03-93ER40773)Robert A.Welch Foundation(Grant A0330)
文摘The symmetry energy at the time of the production of intermediate mass fragments(IMFs) is studied using experimentally observed IMF multiplicities combined with quantum statistical model calculations(QSM of Hahn and St cker).The ratios of difference in chemical potentials between neutrons and protons relative to the temperature,(μn-μp)/T,and the double ratio temperature,T,were extracted experimentally in the reactions of64,70Zn,64Ni+58,64Ni,112,124Sn,197Au,232Th at 40A MeV.The extracted(μn-μp)/TTscales linearly with δNN,where δNN is the asymmetry parameter,(N-Z)/A,of the emitting source and(μn-μp)/T=(11.1 1.4)δNN0.21 was derived.The experimentally extracted(μn-μp)/T and the double ratio temperatures are compared with those from the QSM calculations.The temperatures-,T,and densities,ρ,extracted from the(μn-μp)/T values agreed with those from the double ratio thermometer which used the yield ratios of d,t,h and α particles.However the two analyses of the differential chemical potential analysis and the initial temperature analysis end up almost identical relation between T and ρ.T=5.25±0.75 MeV is evaluated from the(μn-μp)/Tanalysis,but no density determination was possible.From the extracted T value,the symmetry energy coefficient Esym =14.6±3.5 MeV is determined for the emitting source of T=5.25±0.75 MeV.
