水果中微量元素的LIBS检测  

Determination of Trace Elements in Fruit by Laser-induced Breakdown Spectroscopy

作　　者：傅院霞[1,2] 王莉[1] 徐丽[1] 周彧 宫昊[1] FU Yuan-xia;WANG Li;XU Li;ZHOU Yu;GONG Hao(School of Science,Bengbu University,Bengbu,233030,Anhui;Anhui Province Key Laboratory of Optoelectronic Materials Science and Technology,Anhui Normal University,Wuhu,241000,Anhui)

机构地区：[1]蚌埠学院理学院,安徽蚌埠233030 [2]安徽师范大学光电材料科学与技术安徽省重点实验室,安徽芜湖241000

出　　处：《蚌埠学院学报》2020年第5期71-75,93,共6页Journal of Bengbu University

基　　金：国家自然科学基金(11604003);安徽省高等学校自然科学研究重点项目(KJ2019A0857);光电材料科学与技术安徽省重点实验室项目(OMST201902)。

摘　　要：以香蕉、菠萝、猕猴桃三种水果为样品,使用波长为532 nm的激光聚焦到样品表面产生等离子体,然后检测等离子体中原子和离子的发射光谱,分析水果中的微量元素和激光诱导等离子体特性。通过优化实验参数,分析谱线强度和信噪比,得到香蕉、菠萝和猕猴桃的较佳ICCD门延时为500 ns、400 ns和400 ns,较佳门宽为800 ns、600 ns和400 ns;检测到香蕉、菠萝、猕猴桃中含有Mg、Ca、Fe等微量元素,其中菠萝、猕猴桃还检测到微量元素Na;通过Boltzmann斜线法计算电子温度,得到香蕉、菠萝、猕猴桃等离子体的电子温度分别为11606 K、10811 K和10685 K;通过H谱线Stark展宽法,非H谱线Stark展宽法和Saha-Boltzmann方程法计算电子密度,得到的电子密度不相同;分析等离子体的电子温度、电子密度及其数据处理过程中遇到的问题,以期对水果中微量元素的定量分析做参考。Banana,pineapple and kiwifruit were selected as samples for testing.The laser with the wavelength of 532 nm was focused on the samples’surface to generate the plasma.The emission spectrum of the atoms and ions in the plasma were collected.Then the trace elements in fruits and characteristics of laser-induced plasma were analyzed.By optimizing the experimental parameters and analyzing the spectral line intensity and signal-to-noise ratio,the optimal gate delays of ICCD for banana,pineapple and kiwi fruit are 500 ns,400 ns and 400 ns,and the optimal gate widths are 800 ns,600 ns and 400 ns.Trace elements such as Mg,Ca and Fe were detected in bananas,pineapples and kiwifruits,and trace elements of Na was also detected in pineapples and kiwifruits.The electron temperatures of banana,pineapple and kiwifruit plasma were calculated by Boltzmann oblique line method,and the electron temperatures were 11606 K,10811 K and 10685 K respectively.The electron density is calculated by Stark broadening method of H spectral line,Stark broadening method of non-H spectral line and Saha-Boltzmann equation method,and the obtained electron density were different.In order to provide reference for quantitative analysis of trace elements in fruits,the electron temperature and electron density of laser-induced plasma in fruits and the problems encountered in data processing were analyzed.

关 键 词：激光诱导 水果 微量元素 等离子体特性 

分 类 号：O433.4[机械工程—光学工程] TS222[理学—光学]