Title: | [Variation Characteristics and Ozone Formation Potential of Ambient VOCs in Urban Beijing in Summer] |
Author(s): | Zhang R; Sun XS; Wang Y; Wang F; Luo ZY; |
Address: | "Beijing Key Laboratory of Urban Atmospheric Volatile Organic Compounds Pollution Control and Application, National Engineering Research Center of Urban Environmental Pollution Control, Beijing Municipal Research Institute of Eco-Environmental Protection, Beijing 100037, China. Beijing Key Laboratory of Cloud, Precipitation and Atmospheric Water Resources, Field Experiment Base of Cloud and Precipitation Research in North China, China Meteorological Administration, Beijing Weather Modification Center, Beijing 100089, China" |
DOI: | 10.13227/j.hjkx.202204187 |
ISSN/ISBN: | 0250-3301 (Print) 0250-3301 (Linking) |
Abstract: | "To further understand the effect of volatile organic compounds (VOCs) on ozone (O(3)) formation in seasons when ozone (O(3)) pollution occurs frequently, the variation in VOCs, chemical composition characteristics, and ozone formation potential (OFP) were studied, using high-resolution online monitoring data obtained in an urban site of Beijing in the summer of 2019. The results showed that the averaged total mixing ratio of VOCs was (25.12+/-10.11)x10(-9), with alkanes as the most abundant group (40.41%), followed by oxygenated volatile organic compounds (OVOCs) (25.28%) and alkenes/alkynes (12.90%). The diurnal variation in VOCs concentration showed a bimodal pattern with the morning peak appearing from 06:00 to 08:00, when the proportion of alkenes/alkynes increased significantly,indicating that the vehicle exhaust contributed more to VOCs. The VOCs concentration decreased in the afternoon when the proportion of OVOCs showed an upward trend, and the photochemical reaction and meteorological factors had great influences on VOCs concentration and composition.The OFP in urban Beijing in summer was 154.64 mug.m(-3); aromatics, OVOCs, and alkenes/alkynes played dominant roles in OFP; and hexanal, ethylene, and m/p-xylene were the key species. The results suggested the need for the control of vehicle and solvent use and restaurants emissions to reduce the high level of O(3)in urban Beijing in summer. The diurnal variations in ethane/acetylene (E/E) and m/p-xylene/ethylbenzene (X/E) showed that the photochemical-aging of the air masses was obvious, which was jointly affected by photochemical reactions and regional transport. The back-trajectory results indicated a high contribution of southeastern and southwestern air masses to atmospheric alkanes and OVOCs concentration; moreover, aromatics and alkenes were mainly from local sources" |
Keywords: | diurnal variation ozone (O3) ozone formation potential(OFP) urban volatile organic compounds(VOCs); |
Notes: | "PubMed-not-MEDLINEZhang, Rui Sun, Xue-Song Wang, Yu Wang, Fei Luo, Zhi-Yun chi English Abstract China 2023/04/12 Huan Jing Ke Xue. 2023 Apr 8; 44(4):1954-1961. doi: 10.13227/j.hjkx.202204187" |