The coordination of Mg in spinel, diopside and pyrope is 4,6 and 8,respectively. The spectral profiles of these minerals are different, and the Mg K edge shifts towards higher energy with increase in the coordination ...The coordination of Mg in spinel, diopside and pyrope is 4,6 and 8,respectively. The spectral profiles of these minerals are different, and the Mg K edge shifts towards higher energy with increase in the coordination number of Mg. The former may be related to the coordination geometry, and the latter to the Mg—O band distance. Mg K edge(peak 1) tends to shift to higher energy with the increase in Mg-O band distance, but also to shift to lower energy with increase in the band valence of Mg with oxygen. Mg in CaMgSi 2O 6(Di) NaAlSi 3O 8(Ab)glasses may be multiple structural sites.展开更多
采用相图计算(CALPHAD:Calculation of phase diagrams)方法对Zr-X(X=Li,Na,K,Sc,Hf)5个二元体系进行了相图热力学研究.基于实验数据,通过热力学优化计算获得了一套描述液相及(αZr),(βZr),(Li),(Na),(K),(αSc),(βSc),(αHf)和(βHf...采用相图计算(CALPHAD:Calculation of phase diagrams)方法对Zr-X(X=Li,Na,K,Sc,Hf)5个二元体系进行了相图热力学研究.基于实验数据,通过热力学优化计算获得了一套描述液相及(αZr),(βZr),(Li),(Na),(K),(αSc),(βSc),(αHf)和(βHf)相的热力学参数.Zr-Li,Zr-Na和Zr-K体系中的气相视为理想气体.与实验相图数据对比发现,本文获得的热力学参数能够准确地描述实验相平衡数据.展开更多
针对K荧光具有稳定性高、剂量率大、可控性好等优点,设计一套K荧光X射线辐射装置,为核辐射探测器在低能区能量响应呈现出非线性变化趋势提供计量保障。梯形结构设计缩短光束路径,同时有效降低散射干扰;提出以K吸收缘介于辐射体Kα和Kβ...针对K荧光具有稳定性高、剂量率大、可控性好等优点,设计一套K荧光X射线辐射装置,为核辐射探测器在低能区能量响应呈现出非线性变化趋势提供计量保障。梯形结构设计缩短光束路径,同时有效降低散射干扰;提出以K吸收缘介于辐射体Kα和Kβ线之间的材料为次级过滤器,消除L线并减小Kβ相对于Kα线的强度得到参考辐射场。通过蒙特卡罗程序模拟,结果表明:在8.64~98.4 ke V能量范围内,可以找到相应的K吸收缘获取纯度较高的单能荧光参考辐射场。展开更多
文摘The coordination of Mg in spinel, diopside and pyrope is 4,6 and 8,respectively. The spectral profiles of these minerals are different, and the Mg K edge shifts towards higher energy with increase in the coordination number of Mg. The former may be related to the coordination geometry, and the latter to the Mg—O band distance. Mg K edge(peak 1) tends to shift to higher energy with the increase in Mg-O band distance, but also to shift to lower energy with increase in the band valence of Mg with oxygen. Mg in CaMgSi 2O 6(Di) NaAlSi 3O 8(Ab)glasses may be multiple structural sites.
文摘采用相图计算(CALPHAD:Calculation of phase diagrams)方法对Zr-X(X=Li,Na,K,Sc,Hf)5个二元体系进行了相图热力学研究.基于实验数据,通过热力学优化计算获得了一套描述液相及(αZr),(βZr),(Li),(Na),(K),(αSc),(βSc),(αHf)和(βHf)相的热力学参数.Zr-Li,Zr-Na和Zr-K体系中的气相视为理想气体.与实验相图数据对比发现,本文获得的热力学参数能够准确地描述实验相平衡数据.
文摘针对K荧光具有稳定性高、剂量率大、可控性好等优点,设计一套K荧光X射线辐射装置,为核辐射探测器在低能区能量响应呈现出非线性变化趋势提供计量保障。梯形结构设计缩短光束路径,同时有效降低散射干扰;提出以K吸收缘介于辐射体Kα和Kβ线之间的材料为次级过滤器,消除L线并减小Kβ相对于Kα线的强度得到参考辐射场。通过蒙特卡罗程序模拟,结果表明:在8.64~98.4 ke V能量范围内,可以找到相应的K吸收缘获取纯度较高的单能荧光参考辐射场。
