Results 161 to 170 of about 21,982 (208)

Fourier Transform Photoacoustic Spectroscopy

Applied Physics Letters, 1978
Visible-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.
Michael M. Farrow, Roger K. Burnham, Edward M. Eyring   +2 more
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Resonant Photoacoustic Spectroscopy

1983
Nearly 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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Nonlinear Photoacoustic Spectroscopy

Second International Meeting on Photoacoustic Spectroscopy, 1981
The capabilities of the photoacoustic technique to measure small absorptivities is now well documented. This capability is now being exploited to measure nonlinear absorption in a variety of materials. The potentials of this new non-linear spectroscopic techniques are just beginning to be realized.
Eric W. Van Stryland, Milton Woodall, M. J. Soileau, William E. Williams   +3 more
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Photoacoustic Overtone Spectroscopy

Second International Meeting on Photoacoustic Spectroscopy, 1981
The introduction of intracavity dye-laser photoacoustic detection inaugurated the, hitherto unexplored, area of gas-phase vibrational overtone molecular spectroscopy.1–3 We have used this technique to detect extremely weak overtone absorptions in more than 50 molecular systems in the spectral region 1000–400 nm.
K. V. Reddy, M. J. Berry
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Photoacoustic Correlation Spectroscopy

Optical Remote Sensing of the Atmosphere, 1990
Photoacoustic (PA) correlation spectroscopy offers some advantages over conventional correlation spectroscopy in that the PA detector requires no cooling. The method has been proposed earlier (Perlmutter, *et al) , but was not considered sensitive enough to warrant further work.
P. Shakkottai, J. S. Margolis
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Standoff Photoacoustic Spectroscopy of Explosives

Applied Spectroscopy, 2016
Detection and identification of unknown and possibly hazardous materials is a vital area of research to which infrared (IR) spectroscopy is ideally suited. Infrared absorption spectra can be measured with many sensing paradigms of which photoacoustic spectroscopy (PAS) is a sensitive and flexible variant.
Logan S, Marcus, Ellen L, Holthoff, Paul M, Pellegrino   +2 more
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Photoacoustic Spectroscopy — Photoacoustic and Photothermal Effects

1990
Definition. Photoacoustic (PA) or optoacoustic measurements in the original, strict sense comprise the detection of acoustic waves which arise from non-radiative de-excitation (radiationless transition) of the sample as a consequence of absorption of continuously amplitude-modulated light.
C. Buschmann, H. Prehn
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Photoacoustic spectroscopy of solids

The Journal of the Acoustical Society of America, 1973
There are a great many substances, both organic and inorganic, that, because of their physical state, cannot be readily studied by conventional absorption or reflection techniques. In photoacoustic spectroscopy, light absorbed by the sample is converted into a measurable acoustic signal, and spectra closely corresponding to optical absorption spectra ...
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Dermatological photoacoustic spectroscopy

1981
Photoacoustic spectroscopy, a new and developing technique, has generated considerable interest as a spectroscopic tool for the studying of solid, semisolid and biological samples. This technique allows the depth profiles of both the optical and thermal properties of skin to be determined in cases where other techniques can be applied only with ...
E. Pines, T. Cunningham
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High-sensitivity surface-photoacoustic spectroscopy

Optics Letters, 1990
The sensitivity of surface-acoustic-wave detection is extended by several orders of magnitude to a surface-specific absorbance of alphal ~ 10(-9) for a power density of 1 GW/cm(2) using a narrow-bandwidth interdigitated surface-acousticwave detector and an optical irradiation pattern to provide a matched acoustic signal. Major advantages include narrow-
M Y, Raja, D W, Reicher, S R, Brueck, J R, McNeil, D E, Oates   +4 more
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