【摘要】 NO2是大气污染的主要污染物之一,是形成光化学烟雾与酸雨的主要因素之一。吸收光谱法是有害气体检测的重要手段与发展方向。本文采用差分方法,采用蓝光激光外调制,建立实验系统,进行NO2气体浓度定点和局部测量,使信噪比不受探测器、放大器及背景噪声的限制,可有效提高气体检测灵敏度。通过光谱分析,实验光谱与标准光谱拟合、浓度反演计算等数据处理过程,取得了较好的实验结果,验证了检测系统的有效性。更多还原

【Abstract】 NO2 is one of the main pollutants of air pollution,and is also the formation of photochemical smog and acid rain.In this paper,We fixed differential detection with laser external modulation to improve signal to noise ratio(SNR) from the detector and eliminate background interfere.The minimum detectable concentration increases several orders of magnitude,relatively.We analyze the basic principles of detection,the experimental spectrum and standard spectrum fitting.The results verified the effectiveness of the experimental system.更多还原