Abstract. In this paper, the continuous on-line measurements of isoprene in the atmosphere have been carried out by using the Differential Optical Absorption Spectroscopy (DOAS) in the band of 202.71–227.72 nm for the first time. Under the zero optical path in the laboratory, different equivalent concentrations of isoprene were measured by the combination of known concentration gas and series calibration cells. The correlation between the measured concentrations and the equivalent concentrations was 0.9996, and the slope was 1.065. The correlation coefficient between DOAS and on-line VOCs instrument is 0.85 and the slope is 0.86 in the comparison of 23 days field observation. It is estimated that the detection limit of isoprene with DOAS is about 0.1 ppb at an optical path of 75 m, and it is verified that isoprene could be measured in the ultraviolet absorption band using DOAS method with high temporal resolution and low maintenance cost.

中文翻译：

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差分光学吸收光谱法测定异戊二烯的研究

摘要。在本文中，首次使用202.71–227.72 nm波段的差分光吸收光谱法（DOAS）对大气中的异戊二烯进行了连续在线测量。在实验室的零光路下，通过已知浓度的气体和串联校准池的组合测量了不同的异戊二烯等效浓度。测得的浓度与当量浓度之间的相关性是0.9996，斜率是1.065。与23天实地观测的比较，DOAS与在线VOCs仪器之间的相关系数为0.85，斜率为0.86。据估计，在75 m的光路中，使用DOAS的异戊二烯的检出限约为0.1 ppb，