摘要
随着现代化工业的发展,大气污染越来越严重,吸收光谱法是检测大气污染的重要手段。NO2是大气污染的主要污染物之一,文章将发光二极管作为光源,选择发光光谱范围处于NO2强吸收峰位置的发光二极管,通过测量含有NO2污染物的吸收光谱,利用最小二乘法,将实验得到的吸收光谱与标准谱作拟合运算,反演计算出污染物浓度。分析了检测的基本原理,研究了光谱分析过程,包括实验光谱与标准光谱的拟合、浓度的反演计算等数据处理过程。具体利用NO2在300～500 nm光谱范围内有强吸收的特点,测量了样品中NO2的浓度。实验使用发光二极管作为光源,使检测变得方便快捷,实验装置便于携带,可以随时对待测场所实现高精度的实时在线检测。
Light-emitting diode was used as illuminant in the present paper. The light-emitting diode was chosen according to the high absorption in the range of absorption spectrum of NO2. The pollutant concentration can be calculated by measuring the absorption spectrum, and fitting the experimental absorption spectrum and normal absorption spectrum by means of least square fitting method. The method of measuring nitrogen dioxide concentration making use of absorption spectra was studied, the basle principle was analyzed, the process of data analysis was studied including the fitting of experimental spectrum and standard spectrum, wiping off the slow change, using least-square fitting in reverse calculating of concentration etc. The detecting precision was improved by the method of absorption spectrum. In this experiment the light emitting diode was used as illuminant, whieh made the detecting become not only convenient but also fast, and online real time supervising can be realized. Taking advantage of the characteristic that NO2 has strong absorption in the range of 300-500nm, the NO2 concentration of sample was measured.
出处
《光谱学与光谱分析》
SCIE
EI
CAS
CSCD
北大核心
2009年第6期1672-1674,共3页
Spectroscopy and Spectral Analysis
基金
国家自然科学基金项目(10274080)资助
关键词
吸收光谱
NO2
发光二极管
Absorption spectrum
Nitrogen dioxide
Light emitting diode
