深圳大学学报理工版

利用微型中子源反应堆辐照 55Mn样品,得到放射性核素 56Mn,使用高纯锗探测系统测量 56Mn的能谱,得到 56Mn在不同化合态下的半衰期并进行比较.通过β衰变的费米理论,引入约化电荷计算,对不同化合态下 56Mn的衰变常数与约化电荷进行比对研究.利用同核异能移概念,分析原子价电子的交换和电子云的重叠对 56Mn衰变常数的影响,说明 56Mn半衰期会因为电子密度不同而改变.

The radioactive isotope 56Mn(manganese 56)was produced by activating the 55Mn samples in the miniature neutron source reactor in Shenzhen University. The energy spectrum of 56Mn was detected by the high purity germanium detector system(HPGe system). The half-life of 56Mn in different chemical environments was studied and compared. The reduced charge was calculated by using the Fermi beta-decay theory,then compared with the change of decay constant of 56Mn in different chemical environments. The impact of the valence electron exchange and electron cloud overlap to the decay constant of the 56Mn was analyzed using the theory of the concept of isomer shift.The result is that the half-life of 56Mn is changed due to the variances of electron density.

引言
1 实验
2 结果与讨论
3 结语

图1 深圳大学微型中子源反应堆结构示意图<br/>Fig.1 Structure of miniature neutron source reactor in Shenzhen University

图1 深圳大学微型中子源反应堆结构示意图
Fig.1 Structure of miniature neutron source reactor in Shenzhen University

图2 Mn单质特征γ射线活度随时间变化趋势<br/>Fig.2 The relationship between the activity of specific gamma ray of Mn monomer and time

图2 Mn单质特征γ射线活度随时间变化趋势
Fig.2 The relationship between the activity of specific gamma ray of Mn monomer and time

图3 不同化合物中 56Mn半衰期比较<br/>Fig.3 Half-lives of comparison between 56Mn in different compounds

图3 不同化合物中 56Mn半衰期比较
Fig.3 Half-lives of comparison between 56Mn in different compounds

表1 不同化合物中测得的 56Mn半衰期结果<br/>Table 1 The result of half-decay of 56Mn in different compounds

表1 不同化合物中测得的 56Mn半衰期结果
Table 1 The result of half-decay of 56Mn in different compounds

图4 价电子的交换和电子云的重叠<br/>Fig.4 The exchange of valence electron and the overlap of electron cloud

图4 价电子的交换和电子云的重叠
Fig.4 The exchange of valence electron and the overlap of electron cloud

表2 约化电荷与衰变常数变化的比较<br/>Table 2 Comparing the changes of reduced charge and decay constant

表2 约化电荷与衰变常数变化的比较
Table 2 Comparing the changes of reduced charge and decay constant

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备注

引言

1 实验

2 结果与讨论

3 结语

期刊信息

备注

引言

1 实 验

2 结果与讨论

3 结 语

期刊信息

1 实验

3 结语