Anomalous Absorption and a Qualified Far Infrared Spectrum
HU Yan-qin1, CHEN Yu-jing1, LI Hui-hua2, WANG Hai-shui1*
1. School of Chemistry & Chemical Engineering, South China University of Technology, Guangzhou 510640, China 2. Modern Analytical Center, Shantou University, Shantou 515063, China
Abstract：The ideal 100% line could not be obtained when the content of water vapor in the spectrometer is constant but high during the whole procedure of a far-infrared spectrum collection. This result indicates that anomalous absorption phenomenon takes place in high relative humidity atmosphere. In the present paper，the influences of the relative humidity of ambient air and spectral resolution on anomalous absorption were studied. It was found that both decreasing the water vapor content in the spectrometer and adopting low spectral resolution are effective methods to avoid anomalous absorption. Furthermore，the water vapor bands can be eliminated by “dry air and wet air titration” in the fluctuant humidity. This provides us a quick and economic method to obtain a qualified far infrared spectrum conveniently. It should be noticed that the working condition for “dry air and wet air titration” is low relative humidity to prevent water vapor abnormal absorption.
胡燕琴1，陈玉静1，李惠华2，王海水1* . 反常吸收与高质量的远红外光谱[J]. 光谱学与光谱分析, 2012, 32(02): 339-342.
HU Yan-qin1, CHEN Yu-jing1, LI Hui-hua2, WANG Hai-shui1* . Anomalous Absorption and a Qualified Far Infrared Spectrum. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2012, 32(02): 339-342.
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