[ Instrument Network Instrument Development ] Recently, An Guang's Zhang Weijun research group has made new progress in atmospheric formaldehyde detection. The related results are published in the American Optical Society under the title of "Pptv Quantitative Atmospheric Formaldehyde Measuring Instrument Based on New Spherical Mirror Optical Multi-Position Cell". (OSA) Academic Journal Applied Optics.
New optical multi-channel simulation spot and experimental spot
Guangzhou field observation results
Formaldehyde (HCHO) is an important intermediate in the oxidative degradation of atmospheric volatile organic compounds (VOCs) and plays an important role in the process of ozone (O3) formation and atmospheric pollution of HOx-NOx radical chain circulation. The external field observation of formaldehyde concentration can be used as an important indicator to distinguish between human and biological VOCs, and can be used to verify the accuracy of the model. Its direct and accurate measurement is of great significance for atmospheric chemical research and pollution control.
Researcher Zhao Weixiong and Dr. Fang Bo and others designed a new spherical mirror optical multi-pass cell, which obtained an effective absorption path of 96 meters at 36 cm base length, combined with the use of a 3.5 μm inter-band cascade laser (ICL). The atmospheric formaldehyde measuring instrument based on tunable diode laser absorption spectroscopy (TDLAS) achieves the detection limit of 51pptv (10s, 1σ) and meets the urgent need for atmospheric formaldehyde field observation.
The instrument participated in the large-scale external field observation experiment (PRIDE-GBA) in the 2018 fall of Dawan District, Guangdong, Hong Kong and Macau in Guangzhou. The performance is stable and provides high-quality data support for this observation.
The research work was funded by the Ministry of Science and Technology Key Research and Development Program and the National Natural Science Foundation.
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