期刊
INFRARED PHYSICS & TECHNOLOGY
卷 51, 期 3, 页码 198-206出版社
ELSEVIER
DOI: 10.1016/j.infrared.2007.05.006
关键词
absorption spectroscopy; stable carbon isotope; quantum cascade laser spectrometer
Simultaneous concentration measurements of the three main stable carbon dioxide isotopologueS ((OCO)-O-16-C-12-O-16, (OCO)-O-16-C-13-O-16 and (OCO)-O-18-C-12-O-16) in ambient air are demonstrated. The instrument employs a quasi-room temperature, pulsed quantum cascade laser emitting at 4.3 mu m. Both the laser and the IR detector are thermoelectrically cooled, which greatly facilitates cryogenic-free, continuous operation. The Allan plot of the time series of the retrieved spectroscopic ratio [(CO2)-C-13]/[(CO2)-C-12] shows a variance minimum that corresponds to 0.16 parts per thousand for delta C-13 with an averaging time of about 500 s. To demonstrate the feasibility of high precision in situ isotope ratio measurements, the instrument was operated in the field and provided continuous mixing ratio values for all three CO2 isotopologues at I s time resolution. The spectroscopically derived isotopic ratios were compared to the standard laboratory-based isotope-ratio mass spectrometer measurements made on field-collected flask samples. At stable laser operation, the two data sets agreed within 0.28 parts per thousand. (c) 2007 Elsevier B.V. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据