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Photoacoustic theory

It is well known from photoacoustic theory ( 1) that one can, with thermal waves, obtain Information about the thermal... [Pg.181]

Using the R-G photoacoustic theory ( ), the pressure variations in the cell may be written as ... [Pg.379]

Figure 1. Schematic diagram of a photoacoustic cell used to develop the one-dimensional theory of microphonic PAS by Rosencwaig and Gersho. Figure 1. Schematic diagram of a photoacoustic cell used to develop the one-dimensional theory of microphonic PAS by Rosencwaig and Gersho.
The basic theory of the photoacoustic effect was described by Tam and Patel [279,280] and some of its applications were presented in a review by Braslavsky and Heibel [281], The first use of PAC to determine enthalpies of chemical reactions was reported by the groups of Peters and Braslavsky [282,283], The same groups have also played an important role in developing the methodologies to extract those thermodynamic data from the experimentally measured quantities [282-284], In the ensuing discussion, we closely follow a publication where the use of the photoacoustic calorimety technique as a thermochemical tool was examined [285],... [Pg.190]

Knshnan K (1988) Characterization of semiconductor silicon using the FT-TR microsampling techniques In Messerschmidt RG, Harthcock MA (eds) Infrared microspectroscopy theory and applications Marcel Dekker, New York, 139-151 Kuo MI, McClelland JF, Luo S, Chien PL, Walker RD, Hse CY (1988) Applications of infrared photoacoustic spectroscopy for wood samples Wood Fiber Sci 20 132-145 Lai Y-Z, Sarkanen KV (1975) Structrual variation in dehydrogenation polymers of comferyl alcohol Cellul Chem Technol 9 239-245... [Pg.107]

The theory of rotation effects on prolate luminescent molecules in solution and its experimental verification have been developed and compared. Generalized diffusion equations for the rotational motion of an asymmetric rigid motor have been used to given an expression for steady-state fluorescence depolarization. " The radiationless transition from the first excited singlet state of Eosin has been measured by optoacoustic relaxation, and the absolute fluorescence quantum yields of organic dyes in poly(vinyl alcohol) have also been measured by the photoacoustic method. The accuracy of the method has been discussed in the latter paper. Actinometry in flash photolysis experiments has been assisted by new measurements on the extinction coefficient of triplet benzophenone. Matrix-isolation fluorescence spectrometry has been used to detect polycyclic aromatic hydrocarbons from gas chromatography. ... [Pg.6]

Certain aspects of the photoacoustic effect suggest that this technique might be generally applicable to all chiral solids regardless of crystal class, size or perfection, or strength of absorption. Although subsequent theoretical developments and experimental results have caused us to limit considerably the predicted scope of this method, nevertheless, it is possible now to say clearly that the experiment does work and offers prospects for unique results. In this paper we review briefly the nature of the theory and practice of condensed phase photoacoustic spectroscopy and its extension to the measurement of natural circular dichroism, and present initial results for single crystals and powders. [Pg.376]

The above statements of the nature of the photoacoustic effect are drawn primarily from the conclusions of the theory developed by Rosencwaig and Gersho (R-G) (9), based on a onedimensional thermal piston model. Since this is the starting point for extending the theory of photoacoustic spectroscopy (PAS) to include photoacoustic circular dichroism (PACD), a brief survey of the salient factors and important parameters of that treatment follows. [Pg.377]

From the results of the R-G theory it would appear that detection of circular dichroism photoacoustically would have the following potential applications ... [Pg.378]

In this article, experiments with gases employing a resonant photoacoustic cell are reviewed. In the next chapter the physical processes occurring in an acoustic resonator are analysed. The third chapter describes experimental setups and components used in resonant photoacoustic spectroscopy. In chapter four the theory of acoustic resonators is outlined and the loss mechanisms which dampen the... [Pg.3]

FTIR photoacoustic spectroscopy (PAS) has advantages relative to conventional IR techniques (transmission, reflection and emission) because it is non-destructive, does not involve sample preparation and can probe samples with compositional gradients and layers. The theory, instrumentation, methods and applications of FTIR-PAS are discussed and results are presented on several polymer analyses based on FTIR-PAS. 4 refs. USA... [Pg.60]

Rosencwaig A and Gersho A (1976) Theory of the photoacoustic effect with solids. Journal of Applied Physics 47 64-69. [Pg.3724]

Maccagnani P, Angelucci R, Pozzi P, Dori L, Parisini A, Bianconi M, Benedetto G (1999) Thick porous silicon thermo-insulating membranes. Sens Mater 11 131-147 McDonald FA, Wetsel GC jr (1978) Generalized theory of the photoacoustic effect. J Appl Phys 49 2313-2322... [Pg.862]

Autrey, T., Brown, A. K., Camaioni, D. M., Dupuis, M., Foster, N. S., and Getty, A. 2004. Thermochemistry of aqueous hydroxyl radical from advances in photoacoustic calorimetry and ab initio continuum solvation theory. Journal of the American Chemical Society 126 3680-3681. [Pg.102]

F.J.M. Harren Photoacoustic spectroscopy in trace gas monitoring. In Encyclopedia of Analytical Chemistry Applications, Theory and Instrumentation, ed. by R.A. Meyers (Wiley, New York 2000) p.2203... [Pg.518]

In Chapters 2 to 8 we describe the theory and instrumentation needed for an appreciation of the way that Fourier transform infrared and Raman spectra are measured today. The sampling techniques for and applications of FT-Raman spectrometry are described in Chapter 18. The remaining chapters cover the techniques and applications of absorption, reflection, emission, and photoacoustic spectrometry in the mid- and near-infrared spectral regions. [Pg.18]

There are, however, several occasions when transmission, reflection, or photoacoustic spectra of remote samples simply cannot be measured and emission spectroscopy is the only possible way to obtain qualitative or quantitative information. In this chapter a brief outline of the theory and practice of infrared emission spectrometry is given. [Pg.363]

Optical Spectroscopy, Linear Polarization Theory Photoacoustic Spectroscopy, Theory... [Pg.29]

See also Matrix Isolation Studies By IR and Raman Spectroscopies Nonlinear Optical Properties Nonlinear Raman Spectroscopy, Instruments Nonlinear Raman Spectroscopy, Theory Photoacoustic Spectroscopy, Theory Raman Optical Activity, Applications Raman Optical Activity, Theory Rayleigh Scattering and Raman Spectroscopy, Theory Surface-Enhanced Raman Scattering (SERS), Applications. [Pg.461]


See other pages where Photoacoustic theory is mentioned: [Pg.163]    [Pg.240]    [Pg.49]    [Pg.50]    [Pg.50]    [Pg.55]    [Pg.72]    [Pg.152]    [Pg.229]    [Pg.377]    [Pg.481]    [Pg.716]    [Pg.726]    [Pg.131]    [Pg.30]    [Pg.613]    [Pg.3719]    [Pg.496]    [Pg.524]    [Pg.66]    [Pg.640]    [Pg.364]    [Pg.20]   
See also in sourсe #XX -- [ Pg.379 , Pg.380 ]




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