论文部分内容阅读
氨气是大气中含量最为丰富的碱性痕量气体,氨浓度检测是近年来环境和农业领域的一个重要研究方向。利用可调谐半导体激光吸收光谱(TDLAS)技术,结合波长高频扫描技术和多次反射池技术设计了氨气激光在线检测系统。通过激光中心波长锁定、背景基线拟合、吸收线型拟合、光强归一化和线性最小二乘拟合算法实现了氨浓度的精确反演。分析了系统性能,在24.32m光程下系统检测限为0.157mg/m3。使用该浓度反演方法实现了氨气的高灵敏、高精确在线检测。
Ammonia is the most abundant alkaline trace gas in the atmosphere. Detection of ammonia concentration has been an important research direction in the field of environment and agriculture in recent years. Ammonia laser on-line detection system was designed by using tunable semiconductor laser absorption spectroscopy (TDLAS) technology combined with wavelength high-frequency scanning technology and multi-reflection cell technology. Accurate inversion of ammonia concentration was achieved by laser central wavelength locking, background baseline fitting, absorption line fitting, light intensity normalization and linear least squares fitting algorithm. The system performance was analyzed. The detection limit was 0.157mg / m3 at 24.32m optical path. Using the concentration inversion method to achieve a highly sensitive ammonia, high-precision on-line detection.