Results 31 to 40 of about 1,306,141 (231)
Photoacoustic Spectroscopy [PDF]
, 2020 In its broadest sense, optical spectroscopy can be defined as the study of theinteraction of light with matter. Optical spectroscopy is invaluable in studies on cleanmedia but there are several instances where it is inadequate. In order to solve this problem,several techniques were developed, but these were applicable to only a small category ...
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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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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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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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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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Development of a prototype photoacoustic microscope and spectroscope and advanced semiconductor material characterization [PDF]
, 2012 The thesis can be divided into two parts. In the first part of my thesis, I present the design, construction and test results of a prototype gas-cell Photoacoustic (PA) Spectrometer and Microscope. It is a low cost, non-contact technique, which can
Xu, Lu, Xu, L.
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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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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
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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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