镧元素激光诱导击穿光谱定量分析准确度提高的研究  

Improving Accuracy of Quantitative Analysis of La in Graphite Using Laser-In⁃duced Breakdown Spectroscopy

作　　者：时燕华 刘念 刘舒 王颖 彭玲玲 刘小亮 陈晨 Shi Yanhua;Liu Nian;Liu Shu;Wang Ying;Peng Lingling;Liu Xiaoliang;Chen Chen(Experimental Testing team of Jiangxi Geological Bureau,Nanchang 330003,China;School of Nuclear Science and Engineering,East China University of Technology,Nanchang 330013,China;China Nuclear Industry 23 Construction Co.,Ltd.,Shenzhen 518120,China)

机构地区：[1]江西省地质局实验测试大队,江西南昌330003 [2]东华理工大学核科学与工程学院,江西南昌330013 [3]中国核工业二三建设有限公司,广东深圳518120

出　　处：《稀有金属》2024年第9期1352-1359,共8页Chinese Journal of Rare Metals

基　　金：国家自然科学基金青年基金项目(12005037);江西省自然科学基金项目(20224BAB201021);江西省地质局核与能源类项目(2023HYN08)资助。

摘　　要：基于激光诱导击穿光谱(LIBS)技术对石墨基底中镧(La)元素进行了定量分析和检测准确度提高的研究。受La含量过高的影响,谱线强度与含量不存在明显的线性关系,基本定标法无法构建有效的校正模型,进而分别采用内标法、偏最小二乘法(PLS)及两者相结合的方法进行了校正模型的构建,并验证了回归分析的可行性。结果表明:以CI247.85 nm线为内标线,所有分析线的积分强度与其比值均与La含量具有较好的线性关系,线性相关系数均在0.95以上,其中,LaⅢ237.93 nm分析线具有最佳线性相关性,以其校正模型获取的LIBS预测含量值与真实值的拟合曲线拟合度(R^(2))为0.9881;采用多条谱线的积分强度为自变量,以La含量为因变量,构建PLS-area模型开展多元分析,预测值与真实值的拟合曲线拟合度为0.9705;当采用多条谱线的积分强度比值作为自变量代入PLS算法,即内标法与PLS相结合(PLS-ratio)后,拟合曲线的拟合度最佳,其R^(2)为0.9983;对比3种模型的预测性能可知,PLS-ratio模型的反演预测精度最高,特别是对高含量样品3#~5#,预测相对误差均在4%以内;此外,3种模型均方根误差(RMSEC)分别为0.5407%,0.8497%和0.2029%,PLS-ratio模型的RMSEC最小,显示该方法具有最佳的预测性能。研究结果表明,采用内标法与PLS相结合的多变量线性回归模型能有效减小LIBS分析误差,提高预测能力,为开展材料中La元素的快速分析提供了可靠基础。Lanthanum(La)is one of the light rare earth elements and has been playing a very important role in military industry,food hygiene,electronic science and technology for its special physical and chemical properties.Hence,it is necessary to perform accurate and sensitive analysis of La concentration in materials.Meanwhile,it is significant to realize real-time online detection and analysis dur⁃ing the production process.The traditional chemical analysis methods such as inductively coupled plasma-optical emission spectrometry(ICP-OES),inductively coupled plasma mass spectrometry(ICP-MS)and X-ray fluorescence spectrometry(XRF)are time-consum⁃ing,complex in sampling preparation,expensive in cost and experimental device,which are hard to keep up with the modern analytical and testing technology development.Laser-induced breakdown spectroscopy(LIBS),a form of atomic emission spectroscopy,has been widely deployed as a new elemental analysis technique based on photon emission due to the de-excitation of excited atoms and/or ions from intense laser-induced plasma(LIP)created on target.The technique has the characteristics of rapid analysis,simultaneous analy⁃sis of multiple elements,no or minus sample preparation and real-time online analysis,etc.Thus,it has a tremendous growth and been widely applied in a variety of areas,such as industrial process analysis,environmental monitoring,mineral exploitation,phar⁃maceutical preparation,agriculture and food.With the increasing acceptance of LIBS as a quantitative spectral method for element measurement,there is a need for advanced statistical data analysis methods.Conventionally,the peak intensity or peak area of the emission line of interest is calculated in a LIBS spectrum to construct calibration curves from the known concentration of a set of cali⁃bration samples,the so-called standard calibration curve method is the simplest and most widespread.However,the accurate quantita⁃tive analysis of LIBS is still a challenge due to physical-chemical matrix effects,the ove

关 键 词：激光诱导击穿光谱(LIBS) 镧 定量分析 内标法 偏最小二乘法(PLS) 

分 类 号：TG146.453[一般工业技术—材料科学与工程] O657.38[金属学及工艺—金属材料]