Wada Ryuichi, Orr-Ewing Andrew J
School of Chemistry, University of Bristol, Cantock's Close, Bristol, UK BS8 1TS.
Analyst. 2005 Dec;130(12):1595-600. doi: 10.1039/b511115c. Epub 2005 Oct 5.
The performance of a continuous wave diode laser based cavity ring-down (CRD) spectrometer is demonstrated for retrieval of NO2 mixing ratios in ambient air. Measurements are made at wavelengths around 410 nm, a region free from other spectroscopic interferences, and the instrument is shown to be capable of quantitative and precise NO2 mixing ratio determinations without any requirement for calibration. The minimum concentration of NO2 that can be measured by the spectrometer is estimated to be 0.1 ppbv (parts per billion by volume) in 50 s at atmospheric pressure. Using dynamic dilution of a standard NO2 sample, the performance of the spectrometer has been validated for NO2 measurements over the range of 0.2 to 80 ppbv. NO2 measurements performed directly on laboratory air are compared with data obtained with a calibrated chemiluminescence instrument and shown to be in excellent agreement.
展示了基于连续波二极管激光器的腔衰荡（CRD）光谱仪在测量环境空气中二氧化氮混合比方面的性能。测量在410nm左右的波长下进行，该区域不存在其他光谱干扰，并且该仪器无需校准即可进行二氧化氮混合比的定量和精确测定。在大气压力下，该光谱仪在50秒内可测量的二氧化氮最低浓度估计为0.1 ppbv（体积十亿分之一）。通过对标准二氧化氮样品进行动态稀释，该光谱仪在0.2至80 ppbv范围内的二氧化氮测量性能得到了验证。将直接在实验室空气中进行的二氧化氮测量结果与用校准化学发光仪器获得的数据进行比较，结果显示二者高度吻合。
