摘要
为探索利用激光诱导击穿光谱(Laser-Induced Breakdown Spectroscopy,LIBS)技术对核材料进行定量分析的可行性,以氧化铈代替氧化钚进行了单脉冲激光诱导击穿光谱(Single Pulse Laser-Induced Breakdown Spectroscopy,SP-LIBS)技术的相关研究。利用Boltzmann曲线拟合、Stark展宽与电子密度计算等分析技术,研究了在固体形态下氧化铈的SP-LIBS等离子体的基本性质。研究结果表明:当激光能量为20 mJ时,对氧化铈固体中铈元素分析的最佳延迟时间为0.4μs。延迟时间为0.4μs时,采用Ce Ⅱ和Si Ⅱ特征谱线数据进行Boltzmann曲线拟合得出的等离子体温度分别为(6 710±805)K和(12 898±1 522)K;采用硅元素Stark展宽多峰拟合结果计算得到的电子密度为(2.88±0.57)×1018cm-3。这些研究结果表明:在该实验条件下等离子体满足局部热动力学平衡条件。
[Background] The analysis and determination of nuclear material is an important part in nuclear safeguards. Laser-induced breakdown spectroscopy(LIBS) is a very promising technology in material quantitative analysis.[Purpose] This study aims to explore the feasibility of using LIBS technology to analyze nuclear materials of CeO2 as a substitute for PuO2. [Methods] By using single pulse laser-induced breakdown spectroscopy(SP-LIBS),the main properties of CeO2 plasma when samples were in solid form were investigated. Boltzmann curve fitting,Stark broadening analysis and electron density calculation were employed to study the basic properties of SP-LIBS plasma of CeO2 in solid state. [Results] The results showed that under the condition of 20 mJ single pulse laster energy, the best delay time for quantitative analysis is 0.4 μs. Simultaneously, plasma temperatures of Ce Ⅱ and Si Ⅱ obtained by Boltzmann curve fitting of their spectral lines were(6 710±805) K and(12 898±1 522) K, respectively,when delay time was set at 0.4 μs, and the electron density calculation derived from multi-peaks fit of Stark broadening by Si element spectral lines is(2.88±0.57)×1018 cm-3. [Conclusion] Under the established experimental condition, the plasma of CeO2 satisfies local thermodynamic equilibrium(LTE) condition, and these results of this study provide reference basis for the quantitative analysis of nuclear material by using LIBS technology.
作者
王祥丽
高智星
程毅梅
WANG Xiangli;GAO Zhixing;CHENG Yimei(China Institute of Atomic Energy,Beijing 102413,China)
出处
《核技术》
CAS
CSCD
北大核心
2020年第11期1-6,共6页
Nuclear Techniques
基金
国防预研基金项目(No.AA16004003)资助。
