Results 21 to 30 of about 218 (120)
In this paper, a highly sensitive and integrated near-infrared CO2 sensor was developed based on quartz-enhanced photoacoustic spectroscopy (QEPAS).
Yihua Liu +9 more
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This research proposes a method for the simultaneous acquisition of the second harmonic (2f) signal of quartz-enhanced photoacoustic spectroscopy (QEPAS) and the first harmonic (1f) signal of quartz-enhanced photothermal spectroscopy (QEPTS) based on the
Hao Liu +5 more
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Detection of Molecular Oxygen at Low Concentrations Using Quartz Enhanced Photoacoustic Spectroscopy
Molecular oxygen is detected at low concentrations using photoacoustic spectroscopy despite its unfavorable photoacoustic properties. The system consists of a seed laser diode, a tapered amplifier and a quartz tuning fork based spectrophone, thus ...
Andreas Pohlkötter +3 more
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Spider Silk-Improved Quartz-Enhanced Conductance Spectroscopy for Medical Mask Humidity Sensing
Spider silk is one of the hottest biomaterials researched currently, due to its excellent mechanical properties. This work reports a novel humidity sensing platform based on a spider silk-modified quartz tuning fork (SSM-QTF). Since spider silk is a kind
Leqing Lin +11 more
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Photoacoustic Techniques for Trace Gas Sensing Based on Semiconductor Laser Sources
The paper provides an overview on the use of photoacoustic sensors based on semiconductor laser sources for the detection of trace gases. We review the results obtained using standard, differential and quartz enhanced photoacoustic techniques.
Vincenzo Spagnolo +3 more
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Benzene sensing by Quartz Enhanced Photoacoustic Spectroscopy at 14.85 µm
Benzene is a gas known to be highly pollutant for the environment, for the water and cancerogenic for humans. In this paper, we present a sensor based on Quartz Enhanced Photoacoustic Spectroscopy dedicated to benzene analysis. Exploiting the infrared emission of a 14.85 µm quantum cascade laser, the sensor is working in an off-beam configuration ...
Diba Ayache +7 more
openaire +2 more sources
Quartz-enhanced photoacoustic spectroscopy employing pilot line manufactured custom tuning forks
Pilot line manufactured custom quartz tuning forks (QTFs) with a resonance frequency of 28 kHz and a Q value of >30, 000 in a vacuum and ∼ 7500 in the air, were designed and produced for trace gas sensing based on quartz enhanced photoacoustic ...
Huadan Zheng +19 more
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1D U-Net Enhanced QEPAS Sensor for Trace Water Vapor Detection
We report a deep learning-assisted quartz-enhanced photoacoustic spectroscopy (QEPAS) sensor for trace water vapor detection in air. A 1392 nm butterfly-packaged DFB laser is wavelength-modulated at f0/2, and the QEPAS signal is retrieved by second ...
Huiming Xiao +13 more
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Review of Recent Advances in QEPAS-Based Trace Gas Sensing
Quartz-enhanced photoacoustic spectroscopy (QEPAS) is an improvement of the conventional microphone-based photoacoustic spectroscopy. In the QEPAS technique, a commercially available millimeter-sized piezoelectric element quartz tuning fork (QTF) is used
Yufei Ma
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Highly Sensitive Capacitive MEMS for Photoacoustic Gas Trace Detection
An enhanced MEMS capacitive sensor is developed for photoacoustic gas detection. This work attempts to address the lack of the literature regarding integrated and compact silicon-based photoacoustic gas sensors. The proposed mechanical resonator combines
Tarek Seoudi +7 more
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