Benchmark experiment on slab^(238)U with D-T neutrons for validation of evaluated nuclear data

A benchmark experiment on^(238)U slab samples was conducted using a deuterium-tritium neutron source at the China Institute of Atomic Energy.The leakage neutron spectra within energy levels of 0.8-16 MeV at 60°and 120°were measured using the time-of-flight method.The samples were prepared as rectangular slabs with a 30 cm square base and thicknesses of 3,6,and 9 cm.The leakage neutron spectra were also calculated using the MCNP-4C program based on the latest evaluated files of^(238)U evaluated neutron data from CENDL-3.2,ENDF/B-Ⅷ.0,JENDL-5.0,and JEFF-3.3.Based on the comparison,the deficiencies and improvements in^(238)U evaluated nuclear data were analyzed.The results showed the following.(1)The calculated results for CENDL-3.2 significantly overestimated the measurements in the energy interval of elastic scattering at 60°and 120°.(2)The calculated results of CENDL-3.2 overestimated the measurements in the energy interval of inelastic scattering at 120°.(3)The calculated results for CENDL-3.2 significantly overestimated the measurements in the 3-8.5 MeV energy interval at 60°and 120°.(4)The calculated results with JENDL-5.0 were generally consistent with the measurement results.

基于遗传算法的轴流风机后导叶匹配性优化

利用多岛遗传算法(MIGA)在高度非线性优化问题上的强大全局寻优能力,结合椭球基(EBF)神经网络近似模型,通过翼型弯曲角、叶片安装角、翼型弦长、轴向间隙四个设计参数变化下的CFD三维数值模拟,得到了一种可自动对单级轴流风机后导叶进行优化设计的方法。结果表明,后导叶叶片安装角对风机全压影响较大,叶片安装角和弯曲角的变化减小了导叶进口气流负攻角,消除了原后导叶压力面的气体回流与涡旋。优化后的导叶压力面的流动得到改善,使风机全压提高了6.73%。

Research on the effect of kunfukang capsule on improving uterine microcirculation in patients with sequelae of pelvic inflammatory disease and its influence on levels of crp, gm-csf and mcp-1 in peripheral blood

Objective:To investigate the clinical effect of kunfukang capsule on improving uterine microcirculation in patients with sequelae of pelvic inflammatory disease, and to observe its influence on levels of CRP, GM-CSF and MCP-1 in peripheral blood.Methods: 126 patients with pelvic inflammatory disease sequelae admitted to our hospital from January 2017 to June 2018 were selected and divided into control group and observation group with 63 cases in each group according to the random number table method. Patients in the control group were given azithromycin tablets orally, while patients in the observation group were treated with kunfukang capsule on the basis of control group,7days for a course of treatment, 4 courses of continuous treatment. The purpose of this study was to compare the clinical effects of treatment between the two groups, evaluate the TCM syndrome score, observe the levels of CRP, GM-CSF and MCP-1 in uterine microcirculation and peripheral blood, and record the adverse reactions of patients during treatment.Results: The effective rate of 90.48% in the observation group was significantly higher than that in the control group of 77.78%(P<0.05). After treatment, the total score of TCM syndromes was significantly lower than that in the control group (P<0.05). The improvement of uterine microcirculation was more obvious, and the PI and RI were significantly decreased compared with the control group, while Vs, Vd and Vm were increased compared with the control group (P<0.05). The levels of CRP, GM-CSF and MCP-1 in peripheral blood were significantly lower than those in the control group (P<0.05). During the treatment, the adverse reaction rate of 7.94% in the observation group was significantly lower than that of the control group of 25.40% (P<0.05).Conclusion: Kun fu kang capsule combined with azithromycin is beneficial to reduce pelvic mass in sequelae of pelvic inflammatory disease and alleviate clinical symptoms. The mechanism may be related to improving the status of uterine microcirculation and inhibiting CRP, GM-CSF and MCP-1 levels in peripheral blood to reduce inflammatory infiltration of pelvic tissue, which is safe and reliable.

Calculation of the wide-angle neutron spectra from the ~9Be(d,xn) reaction in a thick beryllium target

The multi-layer computing model is developed to calculate wide-angle neutron spectra, in the range from0° to 180° with a 5° step, produced by bombarding a thick beryllium target with deuterons. The double-differential cross-sections(DDCSs) for the ~9 Be(d, xn) reaction are calculated using the TALYS-1.8 code. They are in agreement with the experimental data, and are much better than the PHITS-JQMD/GEM results at 15°, 30°, 45° and 60° neutron emission angles for deuteron energy of 10.0 MeV. In the TALYS-1.8 code, neutron contributions from direct reactions(break-up, stripping and knock-out reactions) are controlled by adjustable parameters, which describe the basic characteristics of typical direct reactions and control the relative intensity and the position of the ridgy hillock at the tail of DDCSs. It is found that the typical calculated wide-angle neutron spectra for different neutron emission angles and neutron angular distributions agree quite well with the experimental data for 13.5 MeV deuterons. The multi-layer computing model can reproduce the experimental data reasonably well by optimizing the adjustable parameters in the TALYS-1.8 code. Given the good agreement with the experimental data, the multi-layer computing model could provide better predictions of wide-angle neutron energy spectra, neutron angular distributions and neutron yields for the ~9 Be(d, xn) reaction neutron source.

Measurements of neutron energy spectra of 9Be(d,n)10B reaction with a thick beryllium target

Novel measurements of the neutron energy spectra of the 9Be(d,n)10B reaction with a thick beryllium target are performed using a fast neutron time-of-flight(TOF)spectrometer for the neutron emission angles θ=0°and 45°,and the incident deuteron energies are 250 and 300 keV,respectively.The neutron contributions from the 9Be(d,n)10B reaction are distributed relatively independently for the ground state and the first,second,and third excited states of 10B.The branching ratios of the 9Be(d,n)10B reaction for the different excited states of 10B are obtained for the neutron emission angles θ=0°and 45°,and the incident deuteron energies are 250 and 300 keV,respectively.The branching ratio of the 9Be(d,n)10B reaction for the third excited state decreases with increase in the incident deuteron energy,and the branching ratios for the ground state and the second excited state increase with increase in the neutron emission angle.