首页 | 本学科首页   官方微博 | 高级检索  
     检索      

1.531μm附近NH_3分子痕量探测
引用本文:贾慧,郭晓勇,蔡廷栋,赵卫雄,汪磊,谈图,张为俊,高晓明.1.531μm附近NH_3分子痕量探测[J].光谱学与光谱分析,2009,29(12).
作者姓名:贾慧  郭晓勇  蔡廷栋  赵卫雄  汪磊  谈图  张为俊  高晓明
作者单位:1. 中国科学院安徽光学精密机械研究所环境光学研究室,安徽合肥,230031;中国科学院大气成分与光学重点实验室,安徽合肥,230031
2. 中国科学院空间科学与应用研究中心空间信息与仿真技术研究室,北京,100190
基金项目:国家高技术研究发展计划项目 
摘    要:基于离轴积分腔输出光谱技术(OA-ICOS)的小型集成系统以工作在近红外1.531 μm附近的分布反馈式(DFB)二极管激光器为光源,测量了窒温下各种低浓度NH_3与空气的混合气.首先利用标准浓度的CO_2气体校准得到腔镜的有效反射率R为0.996 9,在此条件下,基长35.8 cm的光学谐振腔作为吸收池可得到115.46 m的吸收光程.NH_3在6 528.764cm~(-1)位置的强吸收谱线被选择用于痕最探测,在100 torr的总压力下,实验测得NH_3的探测极限为2.66 ppmv(S/N~3),之后结合波长调制技术,在信号检测通路中采用锁丰兀放大技术来实现调制信号的二次谐波检测,这可以更好地抑制背景噪声而提高探测信号的信噪比,最终将NH_3的探测极限进一步提高到0.274 ppmv(S/N~3).

关 键 词:离轴积分腔输出光谱技术  波长调制  二次谐波  探测极限

Trace Detection of Ammonia at 1. 531 μm
JIA Hui,GUO Xiao-yong,CAI Ting-dong,ZHAO Wei-xiong,WANG Lei,TAN Tu,ZHANG Wei-jun,GAO Xiao-ming.Trace Detection of Ammonia at 1. 531 μm[J].Spectroscopy and Spectral Analysis,2009,29(12).
Authors:JIA Hui  GUO Xiao-yong  CAI Ting-dong  ZHAO Wei-xiong  WANG Lei  TAN Tu  ZHANG Wei-jun  GAO Xiao-ming
Institution:JIA Hui1,2,GUO Xiao-yong3,CAI Ting-dong1,ZHAO Wei-xiong1,WANG Lei1,TAN Tu1,ZHANG Wei-jun1,GAO Xiao-ming1,2 1.Enviromental Optic Laboratory,Anhui Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,Hefei 230031,China2.Key Laboratory of the Atompheric Composition and Radiation,China3. Space Information & Simulation Technology Lab,Center for Space Science and Applied Research,Beijing 100190,China
Abstract:A compact instrument based on the off-axis integrated-cavity output spectroscopy (ICOS) technology was developed for sensitive measurements of gas mixing ratios (ammonia in air) at room temperature by using fiber-coupled distributed feedback (DFB) diode laser operating at 1. 531 μm. The absorption line of ammonia at 6 528.764 cm~(-1) was chosen for trace detection. The mirrors' effective reflectivity R~2 of 0.996 9 was first calibrated by carbon dioxide under this condition, and the cavity 35.8 cm in length as an absorption cell could yield an optical path of presumably 115.46 m As a result, a minimum detectable concen-tration of approximately 2. 66 ppmv (S/N~3) at the total pressure of 100 torr was obtained. Then the lock-in amplifier was added in the system to acquire the second harmonic signal by combination of wavelength modulation technology, which could bet-ter suppress background noise and improve the signal-to-noise ratio, and a detection limit of 0.293 ppmv (S/N~3) was achieved eventually. This work demonstrated the potential of the system for a range of atmospheric species sensing in the future.
Keywords:NH_3  Off-axis integrated-cavity output spectroscopy  Wavelength modulation  Second harmonic  Ammonia  Detectionlimit
本文献已被 CNKI 万方数据 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号