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Updated: Jun 10, 2026
08:52
Near-Infrared Temperature Measurement Technique for Water Surrounding an Induction-heated Small Magnetic Sphere
Published on: April 30, 2018
Quantitative determination by temperature dependent near-infrared spectra
Xueguang Shao1, Jun Kang, Wensheng Cai
1Research Center for Analytical Sciences, College of Chemistry, Nankai University, Tianjin 300071, PR China. xshao@nankai.edu.cn
Talanta
|August 4, 2010
Summary
Near-infrared (NIR) spectroscopy can determine solution composition by analyzing temperature effects. A quantitative spectra-temperature relationship (QSTR) model predicts temperature, enabling concentration analysis in mixtures.
Area of Science:
- Analytical Chemistry
- Spectroscopy
Background:
- Near-infrared (NIR) spectra are sensitive to environmental variables like temperature.
- Accurate quantitative analysis of mixtures is crucial in various chemical applications.
Purpose of the Study:
- To establish a quantitative spectra-temperature relationship (QSTR) model for NIR spectra.
- To apply this model for the quantitative determination of compositions in various mixtures.
- To explore novel techniques for analytical chemistry using NIR spectroscopy.
Main Methods:
- Partial least squares (PLS) regression was used to build the QSTR model.
- NIR absorption spectra were analyzed in relation to temperature variations.
- Calibration curves were generated to correlate spectral data with composition.
Main Results:
- A reliable QSTR model was established for solvents like water and ethanol.
- The model accurately predicts solution temperature from NIR spectra.
- The difference in predicted temperatures quantitatively reflects solution concentration, with correlation coefficients (R) > 0.99.
Conclusions:
- The QSTR model provides a novel method for predicting temperature using NIR spectra.
- This approach enables accurate quantitative determination of mixture compositions.
- The study extends the application of NIR spectroscopy in analytical chemistry.
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