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Updated: Jun 25, 2026
10:42
Infrared Degenerate Four-wave Mixing with Upconversion Detection for Quantitative Gas Sensing
Published on: March 22, 2019
[Application of NIR spectroscopy to multiple gas components identification]
1State Key Lab of Precision Measuring Technology and Instruments, Tianjin University, Tianjin 300072, China. qrb213@163.com
Guang Pu Xue Yu Guang Pu Fen Xi = Guang Pu
|March 3, 2009
Summary
Near-infrared (NIR) spectroscopy accurately monitors multiple volatile organic compounds (VOCs) in situ. This method enables precise, quantitative analysis for environmental monitoring applications.
Area of Science:
- Analytical Chemistry
- Spectroscopy
- Environmental Science
Context:
- In situ monitoring of multiple gas components is crucial for environmental protection.
- Volatile organic compounds (VOCs) pose significant environmental and health risks.
- Near-infrared (NIR) spectroscopy offers a non-invasive analytical technique.
Purpose:
- To analyze the spectral characteristics of propane, propylene, and methylbenzene in the NIR region.
- To develop a quantitative model for determining VOC concentrations using NIR spectra.
- To validate the accuracy and feasibility of NIR spectroscopy for multi-component VOC monitoring.
Summary:
- Spectral characteristics of propane, propylene, and methylbenzene were analyzed between 1620-1750 nm.
- A linear regression model utilizing partial least-squares was established.
- The model accurately predicted concentrations of propane and isobutene in a validation set.
Impact:
- Demonstrates the capability of NIR spectroscopy for easy, accurate, and quantitative in situ monitoring of multiple VOCs.
- Provides a foundation for developing advanced environmental monitoring systems.
- Facilitates real-time assessment of air quality and industrial emissions.
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