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A Review on Photoacoustic Spectroscopy Techniques for Gas Sensing. [PDF]
Sensors (Basel)Wijesinghe DR, Zobair MA, Esmaeelpour M.
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Acetylene-enhanced methane-QEPAS sensing
Optics LettersMethane (CH4), as a critical greenhouse gas and explosive hazard, demands highly sensitive detection for environmental monitoring and industrial safety. To address the limitation of its slow relaxation in quartz-enhanced photoacoustic spectroscopy (QEPAS), this paper reported a novel acetylene (C2H2)-enhanced QEPAS technique for CH4 sensing for the ...
Jin Sun +4 more
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QEPAS sensor using a radial resonator
Applied Physics B, 2021We report on the use of a radial acoustic resonator to increase the acoustic signal of a quartz enhanced photoacoustic spectroscopy (QEPAS) sensor. This approach is an attractive alternative to usual configurations based on microtube longitudinal resonators since it enables to substantially relax laser beam alignment and positioning and thus paves the ...
M. Duquesnoy +5 more
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Compact QEPAS CO2 sensor system using a quartz tuning fork-embedded and in-plane configuration
Optics and Laser Technology, 2023Yi Xie
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Miniaturized QEPAS Detector Concept for Methane
Conference on Lasers and Electro-Optics, 2020QEPAS enables very compact detectors due to the small detection volume. Currently limitations originate from bulky control electronics, like lock-in amplifiers. We report on reducing size and energy of FPGA based devices and their application in methane detection.
Hervé Tatenguem +4 more
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QEPAS sensor in a butterfly package and its application
Applied Optics, 2021Molecular gases are highly relevant in healthcare, production control, safety, and environmental monitoring. They often appear in small concentrations. The measurement of trace gases has increasingly become a key technique in those domains. Quartz-enhanced photoacoustic spectroscopy (QEPAS) is a suitable method that can provide the required low ...
Tobias Milde +7 more
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Conference on Lasers and Electro-Optics 2012, 2012
An IR-LED at 3.4 μm and an off-beam QEPAS cell as detector are utilized for absorption spectroscopy. For 10 cm absorption path a detection limit of 382 ppm is achieved for methane.
Stefan Böttger +2 more
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An IR-LED at 3.4 μm and an off-beam QEPAS cell as detector are utilized for absorption spectroscopy. For 10 cm absorption path a detection limit of 382 ppm is achieved for methane.
Stefan Böttger +2 more
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QEPAS spectrophones: design, optimization, and performance
Applied Physics B, 2010The impact of design parameters of a spectrophone for quartz-enhanced photoacoustic spectroscopy on its performance was investigated. The microresonator of spectrophone is optimized based on an experimental study. The results show that a 4.4 mm-long tube with 0.6 mm inner diameter yields the highest signal-to-noise ratio, which is ∼30 times higher than
L. Dong +3 more
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A QEPAS Sensor in a Butterfly Package
Optical Sensors and Sensing Congress, 2020Quartz-Enhanced-Photo-Acoustic-Spectroscopy (QEPAS) is a modern, promising trace gas measuring technique. One main advantage of QEPAS over other trace-gas spectroscopes is its size. The miniaturization of the sensor-system is the next big challenge in the development.
Tobias Milde +7 more
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Compact portable QEPAS multi-gas sensor
SPIE Proceedings, 2011A quartz-enhanced photoacoustic spectroscopy (QEPAS) based multi-gas sensor was developed to quantify concentrations of carbon monoxide (CO), hydrogen cyanide (HCN), hydrogen chloride (HCl), and carbon dioxide (CO2) in ambient air. The sensor consists of a compact package of dimensions 25cm x 25cm x 10cm and was designed to operate at atmospheric ...
Lei Dong +3 more
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