New results of two computer experiments on modeling of superthermal neutron-nuclear combustion of natural uranium for two different flux densities of external neutron source and duration of half a year each are presen...New results of two computer experiments on modeling of superthermal neutron-nuclear combustion of natural uranium for two different flux densities of external neutron source and duration of half a year each are presented. The simulation results demonstrate the dependence of the autowave combustion modes on the parameters of the external source.展开更多
Neutron activation analysis technique of the Gd2O2S:М scintillation ceramics was developed. The concentrations of 15 trace, minor and major elements (As, Ce, Co, Cr, Cs, Eu, Fe, La, Sc, Tb, Zn, Zr, Pr, Gd, Na) have b...Neutron activation analysis technique of the Gd2O2S:М scintillation ceramics was developed. The concentrations of 15 trace, minor and major elements (As, Ce, Co, Cr, Cs, Eu, Fe, La, Sc, Tb, Zn, Zr, Pr, Gd, Na) have been measured with the instrumental neutron activation analysis of the Gd2O2S:Pr sample. The concentrations range of the determined elements is from 3 × 10-8 to 2.0% in mass. The determination limit of the elements was calculated to be (0.6 - 1.3 × 10-8% in mass).展开更多
The distribution of the neutron spectra in the thermal column hole of Xi'an pulse reactor was measured with the time-of-flight method.Compared with the thermal Maxwellian theory neutron spectra,the thermal neutron...The distribution of the neutron spectra in the thermal column hole of Xi'an pulse reactor was measured with the time-of-flight method.Compared with the thermal Maxwellian theory neutron spectra,the thermal neutron spectra measured is a little softer,and the average neutron energy of the experimental spectra is about 0.042±0.01 eV.The thermal neutron fluence rate at the front end of thermal column hole,measured with gold foil activation techniques,is about 1.18×105 cm-2 s-1.The standard uncertainty of the measured thermal neutron fluence is about 3%.The spectra-averaged cross section of 197Au(n,γ) determined by the experimental thermal neutron spectra is(92.8±0.93) ×10-24 cm2.展开更多
文摘New results of two computer experiments on modeling of superthermal neutron-nuclear combustion of natural uranium for two different flux densities of external neutron source and duration of half a year each are presented. The simulation results demonstrate the dependence of the autowave combustion modes on the parameters of the external source.
文摘Neutron activation analysis technique of the Gd2O2S:М scintillation ceramics was developed. The concentrations of 15 trace, minor and major elements (As, Ce, Co, Cr, Cs, Eu, Fe, La, Sc, Tb, Zn, Zr, Pr, Gd, Na) have been measured with the instrumental neutron activation analysis of the Gd2O2S:Pr sample. The concentrations range of the determined elements is from 3 × 10-8 to 2.0% in mass. The determination limit of the elements was calculated to be (0.6 - 1.3 × 10-8% in mass).
文摘The distribution of the neutron spectra in the thermal column hole of Xi'an pulse reactor was measured with the time-of-flight method.Compared with the thermal Maxwellian theory neutron spectra,the thermal neutron spectra measured is a little softer,and the average neutron energy of the experimental spectra is about 0.042±0.01 eV.The thermal neutron fluence rate at the front end of thermal column hole,measured with gold foil activation techniques,is about 1.18×105 cm-2 s-1.The standard uncertainty of the measured thermal neutron fluence is about 3%.The spectra-averaged cross section of 197Au(n,γ) determined by the experimental thermal neutron spectra is(92.8±0.93) ×10-24 cm2.
