NO_2分子高灵敏度痕量探测技术研究  

High-sensitive trace detection of NO_2 with broadband cavity-enhanced spectroscopy

作　　者：董美丽[1] 徐学哲[1] 赵卫雄[1] 顾学军[1] 胡长进[1] 盖艳波[1] 高晓明[1] 黄伟[1] 张为俊[1] 

机构地区：[1]中国科学院安徽光学精密机械研究所,安徽合肥230031

出　　处：《应用光学》2014年第2期264-269,共6页Journal of Applied Optics

摘　　要：搭建了一台基于蓝光LED的非相干宽带腔增强吸收光谱系统,并将其应用于NO2分子的高灵敏度痕量探测研究。在3s采样时间下,系统探测灵敏度为3.2×10-9 cm-1(1σ),对应NO2的探测极限约为187pmol/mol。利用Allan方差对系统最佳采样时间及系统稳定性进行分析,当采样时间延长至30s时,系统的探测极限可提高至44pmol/mol。将该系统应用于实际大气中NO2的连续测量,其测量结果与商业化NOx分析仪(Thermo 42i)进行了比对测试。A blue light emitting diode(LED)based incoherent broadband cavity-enhanced absorption spectroscopy(IBBCEAS)instrument was set up for high sensitive detection of NO2 molecule.A detection sensitivity of 3.2×10-9 cm-1(1σ,300ms integrating time,and 10times average)was demonstrated on the basis of absorption spectroscopy of NO2,corresponding to a minimum detection concentration of about 187pmol/mol for NO2.The measurement sensitivity and optimum acquisition time of the IBBCEAS system were evaluated using Allan variance analysis.The detection limit of 44pmol/mol for NO2 was achieved with an optimum acquisition time of 30s.The IBBCEAS measured NO2 data in ambient air were compared to the values measured with an on-line NOx analyzer(Thermo 42i).Result shows a good agreement between the NOx analyzer and the IBBCEAS.

关 键 词：激光光谱 非相干宽带腔增强吸收光谱 NO2分子 高灵敏度痕量探测 

分 类 号：X831[环境科学与工程—环境工程]