A new portable open-path instrument for ambient NH_(3) and on-road emission measurements  

作　　者：Wenhao Dai Shanshan Wang Sanbao Zhang Jian Zhu Chuanqi Gu Zhibin Sun Ruibin Xue Bin Zhou 

机构地区：[1]Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP3),Department of Environmental Science and Engineering,Fudan University,Shanghai 200438,China [2]Institute of Eco-Chongming(IEC),Shanghai 202162,China [3]Institute of Atmospheric Sciences,Fudan University,Shanghai 200433,China

出　　处：《Journal of Environmental Sciences》2024年第2期606-614,共9页环境科学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China (Nos.21976031,42075079,and 22176037)。

摘　　要：Increased attentions to vehicle emission of NH_(3)have been paid since it is generally regarded as an important source in urban areas.Here,we developed a movable instrument based on Differential Optical Absorption Spectroscopy(DOAS)principle for detecting on-road NH_(3),which can avoid the losses in the sampling process attributed to the non-sampling methods.For this mobile DOAS,the temporal resolution,detection limit and relative error for NH_(3)were 1 min,2.29 ppbv and 4.57%±2.44%,respectively.By employed to the on-road measurements along the arterial highway in Shanghai,the spatial distributions of NH_(3)and NO were obtained,and their dependence of traffic and road conditions were studied.The slopes of linear regression between NH_(3)and NO were 0.40,0.02 and 0.07 on the Middle Ring Road,Outer Ring Road and Chongming Island Ring Road.It indicates that light gasoline vehicles(LGVs)were found to be the main contributor to NH_(3)emissions,while heavy-duty diesel vehicles(HDVs)mainly emitted NO.Based on the measured NH_(3)in the tunnel,the mileagebased NH_(3)emission factor per vehicle was estimated to be 17.9±6.3 mg/km.The reported open-path instrument can be broadly used in on-road pollutant monitoring or vehicle emissions,and the measurements can reveal the real situation of emission characteristics,even find the abnormal operations of vehicle catalyst system.

关 键 词：AMMONIA Traffic emissions DOAS Emission factor Mobile measurements 

分 类 号：X851[环境科学与工程—环境工程]