运用宽带腔增强技术测量NO_2的研究  

Research on Incoherent Broadband Cavity Enhanced Absorption Spectrascopy for Measurements of NO_2

作　　者：李璐[1] 

机构地区：[1]北京大学环境科学与工程学院,北京100000

出　　处：《科学技术与工程》2015年第22期220-223,共4页Science Technology and Engineering

摘　　要：运用宽带腔增强技术对NO2开展测量,采用中心波长为460 nm的高功率的蓝光LED作为光源,测量了在455~465nm波段范围内的NO2的光学吸收。利用氮气和氦气之间的瑞利闪射截面差异较大的原理,对腔镜的反射率进行标定,在455~465 nm波段的镜片反射率都在99.99%以上,在455.2 nm点的最高反射率达到99.990 8%。在腔镜之间的有效腔长为92cm,积分时间为30 s的条件下,测量了含NO2气体光学吸收的光谱。采用DOASIS软件进行了浓度反演,反演的得到的NO2的浓度为（21.25±1.7）ppb,不确定性在8%左右,标准曲线结果为y=1.001x＋0.271,证明该方法测量NO2比较可靠。The incoherent broadband cavity was used to enhance absorption spectrascopy for measurements of NO2 .The blue-light high power LED as the light source was used to measur the absorption of NO2 with the spec-turm range from 455 nm to 465 nm.The calibration principle is that the rayleigh scattering between nitrogen and he-lium have a big difference and the high mirrors calibrating reflectivity from 455 nm to 465 nm all higher than 99.99%, the maximum point at 455.2 nm can reach 99.990 8%.Under the condition that the effective cavity length is 92 cm and the intergral time is 30 s, the sample’ s sperctrum was measured which have NO2 absorption and recovered it by a software named DOASIS.It shows that the NO2 concertration is equivalent to （21.25±1.7） ppb, the uncertainty is approximate 8%.The calibration result y=1.001x＋0.271 show that the technology is very reliable to measure NO2 .

关 键 词：腔增强 测量 NO2 

分 类 号：X831[环境科学与工程—环境工程]