奥运期间北京城区的开放式NH3激光在线监测

NH3是大气成分中最丰富的碱性痕量气体,对中和大气酸性成分以及气溶胶的形成起重要作用.使用基于可调谐半导体激光吸收光谱和开放长光程技术的NH3在线监测系统对北京奥运期间鸟巢附近城区进行了NH3浓度的连续监测.监测结果表明NH<,3>浓度具有明显的日变化周期,基本规律是白天浓度降低,夜晚浓度升高到峰值;NH3的日峰值浓度从北京奥运开始有所下降.研究表明北京城区机动车限行对减小NH3浓度和抑制气溶胶的形成起到了积极作用.

Atmospheric NH3 On-Line Monitoring in Urban Area of Beijing During Olympic Games by Open-Path Laser Techniques

NH is the most abundant alkaline trace gas in the atmosphere which plays an important role in acid deposition and aerosol formation. The NH on-line monitoring system based on tunable diode laser absorption spectroscopy and long open path technology was used to continuously measure atmospheric NH concentration at an urban site near Beijing National Stadium during Beijing Olympic Games. The monitoring results show that the atmospheric NH concentration variation has an obvious diurnal periodicity, the rule is the concentration decreased in the daytime, and increased to the maximum at night. Moreover, the NH peak concentration decreased at the beginning of Beijing Olympic Games. The results reveal the positive effects of auto restriction for reducing NHconcentration and restricting aerosol formation.