Results 11 to 20 of about 120,634 (290)
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
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Miniaturized Photoacoustic Trace Gas Sensing Using a Raman Fiber Amplifier [PDF]
Journal of Lightwave Technology, 2015 This paper presents the development of a Raman fiber amplifier optical source with a maximum output power of 1.1 W centered around 1651 nm, and its application in miniaturized 3D printed photoacoustic spectroscopy (PAS) trace gas sensing of methane. The Raman amplifier has been constructed using 4.5 km of dispersion shifted fiber, a 1651 nm DFB seed ...
Bauer, Ralf +6 more
openaire +4 more sources
Review of Recent Advances in QEPAS-Based Trace Gas Sensing
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
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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Tailoring MXene Thickness and Functionalization for Enhanced Room-Temperature Trace NO2 Sensing
Nano-Micro LettersHighlights Gas-phase functionalization of X-MXene (X = –F, –OH, –O, –Br, –I) films crafted from sub-100 nm thin MXene flakes for highly sensitive NO2 sensors.
Muhammad Hilal +3 more
doaj +2 more sources
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
doaj +3 more sources
Trace Gas Remote Sensing by Lasers [PDF]
Optik & Photonik, 2013 AbstractActive remote sensing represents a promising technology to accurately measure the atmospheric concentration of the climate‐relevant trace gases carbon dioxide and methane. For this application, frequency stabilized laser sources with high pulse energy emitting at specific absorption lines around 1.6 μm wavelength are required.
Oliver Lux +2 more
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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
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Quartz-enhanced photoacoustic-photothermal spectroscopy for trace gas sensing
Optics Express, 2021 A trace gas detection technique of quartz-enhanced photoacoustic-photothermal spectroscopy (QEPA-PTS) is demonstrated. Different from quartz-enhanced photoacoustic spectroscopy (QEPAS) or quartz-enhanced photothermal spectroscopy (QEPTS), which detected only one single kind of signal, QEPA-PTS was realized by adding the photoacoustic and photothermal ...
Yinqiu Hu +4 more
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Direct Bonding SOI Wafer Based Cantilever Resonator for Trace Gas Sensor Application [PDF]
, 2009 A thermal driving and piezoresistive sensing MEMS cantilever resonator has been proposed and developed to construct trace gas detection sensors. The problem of integrating vibration structure, transducers and electric elements is the main concern in the ...
Wei, Gao, Ying, Dong, Zheng, You
core +1 more source