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Updated: May 23, 2026
07:38
Characterization of Biological Absorption Spectra Spanning the Visible to the Short-Wave Infrared
Published on: January 10, 2025
[Anomalous absorption and a qualified far infrared spectrum]
Yan-qin Hu1, Yu-jing Chen, Hui-hua Li
1School of Chemistry & Chemical Engineering, South China University of Technology, Guangzhou 510640, China. huyanqin87@163.com
Guang Pu Xue Yu Guang Pu Fen Xi = Guang Pu
|April 20, 2012
Summary
Anomalous absorption occurs in far-infrared spectroscopy during high humidity. Decreasing water vapor and using low spectral resolution effectively prevent this, enabling qualified spectrum collection.
Area of Science:
- Spectroscopy
- Atmospheric Science
Context:
- Collecting far-infrared spectra is crucial for atmospheric analysis.
- High relative humidity can interfere with spectral data quality.
- Anomalous absorption phenomena have been observed in humid conditions.
Purpose:
- To investigate the impact of relative humidity and spectral resolution on anomalous absorption in far-infrared spectroscopy.
- To identify effective methods for mitigating anomalous absorption during spectrum collection.
Summary:
- An ideal 100% baseline is unattainable in far-infrared spectroscopy with high, constant water vapor content, indicating anomalous absorption.
- Both reducing internal water vapor and employing lower spectral resolution effectively suppress anomalous absorption.
- A
- dry air and wet air titration
- method is proposed for fluctuating humidity, offering a quick and economical solution, provided low relative humidity is maintained to prevent abnormal absorption.
Impact:
- Provides practical strategies to improve the accuracy and reliability of far-infrared spectral data.
- Enables more efficient and cost-effective collection of high-quality spectra in challenging atmospheric conditions.
- Contributes to better understanding and analysis of atmospheric composition using spectroscopic techniques.
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