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Updated: Aug 17, 2026

Measuring Dissolved Methane in Aquatic Ecosystems Using An Optical Spectroscopy Gas Analyzer
Published on: July 26, 2024
[Experimental study on harmonic detection of methane by use of a digital lock-in amplifier]
Lei Dong1, Wei-Guang MA, Wang-Bao Yin
1College of Physics and Electronics Engineering, Shanxi University, State Key Laboratory of Quantum Optics and Quantum Optics Devices, Taiyuan 030006, China.
Abstract:
The harmonic detection of methane at 6105.3694 cm(-1) was measured by use of a digital lock-in amplifier (SR830) remotely controlled by a computer. The programme was written by Visual Basic 6.0 because it has strong function and a friendly appearance. The experimental results are in agreement with theoretical analysis, which fully confirms that a better signal-to-noise ratio (SNR) can be achieved in the high-harmonics detection of trace gases by the digital lock-in amplifier. The method can be applicable to the highly sensitive detection of pollution gases.
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