Results 1 to 10 of about 15,135 (154)
Trace gas sensing based on multi-quartz-enhanced photothermal spectroscopy [PDF]
Photoacoustics, 2020 A multi-quartz-enhanced photothermal spectroscopy (M-QEPTS) based trace gas detection method is reported for the first time. Different from traditional QEPTS sensor employing a single quartz tuning fork (QTF) as a photothermal detector, two QTFs were ...
Yufei Ma +4 more
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A mini-resonant photoacoustic sensor based on a sphere-cylinder coupled acoustic resonator for high-sensitivity trace gas sensing [PDF]
PhotoacousticsThis paper reports a mini-resonant photoacoustic sensor for high-sensitivity trace gas sensing. The sensor primarily contains a sphere-cylinder coupled acoustic resonator, a cylindrical buffer chamber, and a fiber-optic acoustic sensor.
Guojie Wu +9 more
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THz QCL-Based Cryogen-Free Spectrometer for in Situ Trace Gas Sensing [PDF]
Sensors, 2013 We report on a set of high-sensitivity terahertz spectroscopy experiments making use of QCLs to detect rotational molecular transitions in the far-infrared.
Paolo De Natale +5 more
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Review of Recent Advances in QEPAS-Based Trace Gas Sensing [PDF]
Applied Sciences, 2018 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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Photoacoustic Techniques for Trace Gas Sensing Based on Semiconductor Laser Sources
Sensors, 2009 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
doaj +7 more sources
Frontiers in Physics, 2022 In this article, with an anti-resonant hollow core fiber (ARHCF), fiber-enhanced Raman spectroscopy (FERS) for trace-gas sensing in a high-concentration gas background is demonstrated for the first time.
Guochao Qian +8 more
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Chirped Laser Dispersion Spectroscopy for Remote Open-Path Trace-Gas Sensing [PDF]
Sensors, 2012 In this paper we present a prototype instrument for remote open-path detection of nitrous oxide. The sensor is based on a 4.53 μm quantum cascade laser and uses the chirped laser dispersion spectroscopy (CLaDS) technique for molecular ...
Gerard Wysocki, Michal Nikodem
doaj +3 more sources
Photonic Sensors, 2019 Multi-component and multi-point trace gas sensing in the wavelength modulation spectroscopy is demonstrated based on the frequency-division multiplexing and time-division multiplexing technology.
Zongliang Wang +8 more
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Recent Advances in QEPAS and QEPTS Based Trace Gas Sensing: A Review
Frontiers in Physics, 2020 This invited review paper summarizes and discusses developments of QTF based state-of-the-art quartz-enhanced photoacoustic spectroscopy (QEPAS) and quartz-enhanced photothermal spectroscopy (QEPTS) gas sensing techniques over the past 3 years.
Yufei Ma
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Sensitivity of remotely sensed trace gas concentrations to polarisation [PDF]
Atmospheric Measurement Techniques, 2015 Abstract. Current and proposed space missions estimate column-averaged concentrations of trace gases (CO2, CH4 and CO) from high resolution spectra of reflected sunlight in absorption bands of the gases. The radiance leaving the top of the atmosphere is partially polarised by both reflection at the surface and scattering within the atmosphere ...
D. M. O'Brien +2 more
openaire +3 more sources