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Fourier Transform Photoacoustic Spectroscopy
Applied Physics Letters, 1978Visible-light Fourier-transform photoacoustic spectroscopy (FTPAS) of Nd : glass is reported. The combined throughput and multiplex advantages of the interferometer significantly reduce the data collection time and/or improve the signal-to-noise ratio.
Edward M. Eyring +5 more
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Microwave and optical technology letters (Print), 2021
Laser photoacoustic spectroscopy is a laser measurement method with high sensitivity, good selectivity, nondestructive, and fast response (real‐time). In the present work, to detect carbonyl sulfide and ethene gases and measure resonant frequencies and ...
M. R. Mohebbifar
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Laser photoacoustic spectroscopy is a laser measurement method with high sensitivity, good selectivity, nondestructive, and fast response (real‐time). In the present work, to detect carbonyl sulfide and ethene gases and measure resonant frequencies and ...
M. R. Mohebbifar
semanticscholar +1 more source
Photoacoustic Spectroscopy of Condensed Matter
Angewandte Chemie International Edition in English, 1978AbstractPhotoacoustic spectroscopy is a new analytical tool that provides a simple nondestructive technique for obtaining information about the electronic absorption sprctrum of samples such as powders, semisolids, gels, and liquids. It can also be applied to samples which cannot be examined by conventional optical methods.
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Applied Physics Letters, 2021
Multiple-sound-source-excitation quartz-enhanced photoacoustic spectroscopy (MSSE-QEPAS) based on a single-line spot pattern multi-pass cell (MPC) is reported for gas sensing. Compared with conventional QEPAS, the signal is enhanced by a factor of 20.
Ruyue Cui +4 more
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Multiple-sound-source-excitation quartz-enhanced photoacoustic spectroscopy (MSSE-QEPAS) based on a single-line spot pattern multi-pass cell (MPC) is reported for gas sensing. Compared with conventional QEPAS, the signal is enhanced by a factor of 20.
Ruyue Cui +4 more
semanticscholar +1 more source
Applications of Resonant Photoacoustic Spectroscopy
Second International Meeting on Photoacoustic Spectroscopy, 1981The apparatus employed consists of a laser as radiation source, a cylindrical resonator, and the signal processing system. The 3,39 µm or 1,15 µm beam of a He-Ne laser was intensity modulated by a chopper. The chopper frequency was continuously varied in an interval of 100 Hz around the selected acoustic resonance. In most measurements the first radial
J. Röper, K. Frank, Peter Hess
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Resonant Photoacoustic Spectroscopy
1983Nearly one hundred years after Bells discovery, resonant photoacoustic spectroscopy awoke from a long sleep. The introduction of lasers as radiation sources has led to rapid development of photoacoustics in the last ten years. Experimental results obtained under carefully optimized conditions are now in good agreement with theory of resonators.
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Photoacoustic Spectroscopy of Methane
2015Abstract The absorption of light in gases causes heating and subsequent thermal expansion. When this process is modulated or pulsed, acoustic sound waves are generated. In photoacoustic spectroscopy, the absorption is detected by measuring the sound generated as the scanned light source wavelength varies into and out of resonance.
Robert N. Compton, Michael A. Duncan
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A review of all-optical photoacoustic spectroscopy as a gas sensing method
, 2020Photoacoustic spectroscopy (PAS) is an ultrasensitive method for gas sensing, which usually using a capacitive microphone as a signal detector. However, the electric nature of the microphone limits their applications in the circumstances with high ...
Tianhe Yang, Weigen Chen, Pinyi Wang
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Photoacoustic spectroscopy for process analysis
Analytical and Bioanalytical Chemistry, 2005Photoacoustic spectroscopy (PAS) is based on the absorption of electromagnetic radiation by analyte molecules. The absorbed energy is measured by detecting pressure fluctuations in the form of sound waves or shock pulses. In contrast to conventional absorption spectroscopy (such as UV/Vis spectroscopy), PAS allows the determination of absorption ...
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Analytical Aspects of Photoacoustic Spectroscopy
C R C Critical Reviews in Analytical Chemistry, 1984I.INTRODUCTION A.The Optoacoustic Effect The optoacoustic effect arises when an absorbing species (solid, liquid, or gas) is irradiated with modulated electromagnetic radiation in an enclosed chamber. Pressure waves are set up and these can be detected with a sensitive microphone. Thus, an optical event is transformed into an acoustic signal.
P. J. Meylor, D. Betteridge
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