Results 31 to 40 of about 6,705 (186)
Detection of Molecular Oxygen at Low Concentrations Using Quartz Enhanced Photoacoustic Spectroscopy
Sensors, 2010 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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Photonic Sensors, 2019 A trace ammonia (NH3) detection system based on the near-infrared fiber-optic cantilever-enhanced photoacoustic spectroscopy (CEPAS) is proposed. A fiber-optic extrinsic Fabry-Perot interferometer (EFPI) based cantilever microphone has been designed to ...
Min Guo +3 more
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Quartz-enhanced photoacoustic spectroscopy [PDF]
Optics Letters, 2002 A new approach to detecting a weak photoacoustic signal in a gas medium is described. Instead of a gas-filled resonant acoustic cavity, the sound energy is accumulated in a high- Q crystal element. Feasibility experiments utilizing a quartz-watch tuning fork demonstrate a sensitivity of 1.2x10(-7) cm(-1) W/ radicalHz .
A A, Kosterev +3 more
openaire +2 more sources
High-sensitivity all-optical PA spectrometer based on fast swept laser interferometry
Photoacoustics, 2022 A high-sensitivity all-optical photoacoustic spectroscopy based on fast swept laser interferometry is proposed to trace gas detection. The momentary cavity length of the fiber-optic Fabry–Perot microphone is demodulated by a fast swept-laser ...
Xuefeng Mao +4 more
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Quartz-Enhanced Photoacoustic Spectroscopy for One-Health [PDF]
EPJ Web of Conferences, 2023 We report on the development of Quartz-Enhanced Photoacoustic Spectroscopy (QEPAS) technology to detect 8 different air pollutants, namely CH4, NO2, CO2, N2O, CO, NO, SO2 and NH3, with the same acoustic detection module and interchangeable laser sources,
Patimisco Pietro +9 more
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Photo-acoustic dual-frequency comb spectroscopy
Nature Communications, 2020 Here, the authors show that the resolution and speed limitations in broadband photo-acoustic spectroscopy can be overcome by combining dual-comb spectroscopy with photo-acoustic detection.
Thibault Wildi +4 more
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Calibration of a multi-pass photoacoustic spectrometer cell using light-absorbing aerosols [PDF]
Atmospheric Measurement Techniques, 2017 The multi-pass photoacoustic spectrometer (PAS) is an important tool for the direct measurement of light absorption by atmospheric aerosol. Accurate PAS measurements heavily rely on accurate calibration of their signal.
N. Bluvshtein +8 more
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Thermal diffusivity measurement of undoped Yb2O3 oxide by self-made photoacoustic cell
Materials Letters: X, 2023 Photoacoustic spectroscopy is an essential technique for material characterization by measuring acoustic noise inside a cell. In this work, we have fabricated a photoacoustic cell and a pre-amplifier circuit and optimized both for maximum sensitivity ...
Minarul I. Sarkar, Kaushal Kumar
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Metrology and Measurement Systems, 2014 The photoacoustic cell is the heart of the nondestructive photoacoustic method. This article presents a new simple lumped-components CRLC model of the Helmholtz type photoacoustic cell.
Bartłomiej Chrobak Łukasz +1 more
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IEEE Photonics Journal, 2020 A simultaneous in-situ detection technique to obtain multi-optical parameters was proposed. The same 403.56 nm, low power, blue diode laser was used to conduct the cavity ring-down spectroscopy and photoacoustic spectroscopy, which were coupled.
Hua-Wei Jin +5 more
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