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Dual-tube MEMS-based spectrophone for sub-ppb mid-IR photoacoustic gas detection. [PDF]
PhotoacousticsDello Russo S +9 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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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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Photoacoustic gas detection with LED QEPAS
2011 Conference on Lasers and Electro-Optics Europe and 12th European Quantum Electronics Conference (CLEO EUROPE/EQEC), 2011Various configurations and applications have been investigated and realized since the pioneering introduction of quartz-enhanced photoacoustic spectroscopy (QEPAS) by Kosterev et al. in 2002 [1]. However, the required submillimeter diameter of the acoustic resonator demands an excellent beam quality of laser source and precise adjustments of the QEPAS ...
Stefan Bottger +2 more
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