| 1 | 回收CRT锥玻璃部分替代高密度磁铁矿砂在防辐射混凝土中应用的可行性(英文)显示文摘将回收的阴极射线管(CRT)锥玻璃作为辐射屏蔽混凝土中磁铁矿砂的替代材料,其质量替代率分别为0、20%、40%和60%。研究此防辐射混凝土的流动性、表观密度和力学性能,同时采用实验、理论计算和蒙特卡洛粒子(MCNP)模拟程序等方法研究混凝土γ射线的线性衰减系数(μ),质量衰减系数(μ_m)、半值层厚度(h_(HVL))和十分之一层厚度(h_(TVL))等辐射屏蔽参数。实验结果表明,混凝土的流动性显著提高,而表观密度、抗压强度和静弹性模量均略微下降。在相同的γ射线光子能量条件下,μ_m、μ、h_(HVL)和h_(TVL)等参数的计算、模拟和实验结果吻合较好,这表明用MCNP代码模拟材料的γ射线辐射屏蔽参数是可行的。计算结果表明,用CRT锥玻璃部分代替磁铁矿砂制作的混凝土可以在广泛的γ射线光子能量范围内有效地提高μm值,与对照混凝土(M-1)相比,这种混凝土具有几乎相同的辐射屏蔽性能。对流动性能、力学性能和γ射线辐射屏蔽性能的综合比较发现,锥玻璃细骨料替代率为20%-40%的混凝土具有良好的性能。 | 刘华良 石建军 屈慧琼 丁德馨 | 2019 | Transactions of Nonferrous Metals Society of China2019，29，4： | 2 |
| 2 | Study on gamma-ray attenuation characteristics of some amino acids for 133Ba,137Cs, and 60Co sources显示文摘Amino acids are the building blocks of proteins,which are the most abundant macromolecules in living cells.From the standpoint of the photon interaction cross sections of amino acids,the mass attenuation coefficients,half and tenth value layers,mean free path,effective atomic and electronic cross sections,effective atomic number,and effective electron density of fifteen essential amino acids have been determined for 133Ba,137Cs,and 60Co gamma-ray sources.The MCNP-4C code and the XCOM program have been used to calculate these parameters.The results have been compared to the available experimental and theoretical data.The theoretical results agreed with the experimental data,with RD values of ≤±7%.In the energy region of 81-1332.5 keV,it was found that the μm,σa,and revalues of the amino acids decreased as the photon energy increased,and the increasing density of amino acids had no steady effect on these quantities.Additionally,results demonstrated that the HVL,TVL,and MFP values increased with the increase in photon energy.The μm,σa,and Zeff values of aspartic acid were the highest among those of all amino acids,and they were the lowest for isoleucine.The Zeff value of each sample containing H,C,N,and O atoms was nearly constant in the studied energy region.The Neffvalues of the studied amino acids varied in the range of 3.14×10^23-3.44×10^23 electron/g.Furthermore,the Neffvalues were approximately independent of the amino acid type in this energy region. | Reza Bagheri Ali Yousefi Seyed Pezhman Shirmardi | 2020 | Nuclear Science and Techniques2020，31，2： | 1 |
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