近红外激光甲烷同位素丰度传感器  

Near-Infrared Laser Sensor for Detection of Methane Isotope Abundance

作　　者：张天羽 刘志伟[1,2] 张磊 卢宏斌[1,2] 郑传涛 王一丁 Zhang Tianyu;Liu Zhiwei;Zhang Lei;Lu Hongbin;Zheng Chuantao;Wang Yiding(State Key Laboratory of Integrated Optoelectronics,College of Electronic Science and Engineering,Jilin University,Changchun,Jilin 130012,China;Jilin Provincial Engineering Research Center of Infrared Gas Sensing Technique,Changchun,Jilin 130012,China)

机构地区：[1]吉林大学集成光电子学国家重点联合实验室,电子科学与工程学院,吉林长春130012 [2]吉林省红外气体传感技术工程研究中心,吉林长春130012

出　　处：《光学学报》2021年第10期187-194,共8页Acta Optica Sinica

基　　金：国家重点研发计划(2016YFC0303902);国家自然科学基金(61775079,61627823,61960206004);吉林省科技发展计划(20180201046GX,20190101016JH,20200401059GX)。

摘　　要：面向石油化工等领域的气体检测分析应用,本团队采用可调谐激光二极管吸收光谱技术,研制了一种近红外激光甲烷(CH_(4))同位素丰度传感器。为了提高同位素丰度的检测稳定性,采用自主开发的双比例阀压力控制模块动态控制气室压强。设定目标压强为13.332 kPa,30 min压强监测结果的均值为13.326 kPa,1σ标准差为25 Pa。为了提高同位素丰度的检测精度,采用线性回归算法替代传统的吸光度峰值比方法,并使用体积分数为5×10^(-3)的标准CH_(4)气体开展检测实验,将两种方法的检测结果进行了对比。结果表明:使用吸光度峰值比方法得到的同位素丰度(δ13CH_(4))均值为1.633%,1σ标准差为0.962%,该结果与理论值偏差较大,且稳定性较差;使用线性回归算法得到的1σ标准差为0.367%,均值为-4.652%,与自然界甲烷的同位素丰度结果一致,该算法检测结果的稳定性是吸光度峰值比方法的2.62倍。本文提出的压力控制方案和线性回归算法,为研制可实用化的同位素丰度传感器奠定了基础,在环境保护、资源勘探等领域具有潜在的应用前景。In this paper,we developed a near-infrared laser sensor for the detection of methane(CH_(4))isotope abundance with tunable laser diode absorption spectroscopy for gas detection and analysis applications in petrochemical and other fields.To improve the stability of isotope abundance detection,we adopted a customized pressure control module with two electronic proportional valves to dynamically control the pressure of the gas cell.With the target pressure being set to 13.332 kPa,the average monitoring pressure in 30 min was 13.326 kPa,and the 1σstandard deviation was 25 Pa.To improve the detection accuracy of isotope abundance,we applied a linear regression algorithm instead of the traditional absorbance maximum ratio method.The detection experiment was carried out with 5×10^(-3)(volume fraction)standard CH_(4)gas,and the results of the two methods were compared.The results demonstrate that the average isotope abundance(δ13CH_(4))obtained by the absorbance maximum ratio method is 1.633%,and the 1σstandard deviation is 0.962%.The results largely deviate from the theoretical values and have poor stability.The 1σstandard deviation obtained by the linear regression algorithm is 0.367%,and the average value is-4.652%,which is consistent with the isotope abundance results of natural CH_(4).The stability of the linear regression algorithm detection results is three times that of the maximum ratio method.The pressure control scheme and linear regression algorithm proposed in this article lay a foundation for the development of practical isotope abundance sensors and show potential application prospects in environmental protection,resource exploration,and other fields.

关 键 词：光谱学 红外光谱 线性回归算法 压力控制 同位素检测 

分 类 号：TN21[电子电信—物理电子学]