1208
2003
eng
postprint
0
2007-04-20
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Optical sensing with photon density waves: investigation of model media
Investigations with frequency domain photon density waves allow elucidation of absorption and scattering properties of turbid media. The temporal and spatial propagation of intensity modulated light with frequencies up to more than 1 GHz can be described by the P1 approximation to the Boltzmann transport equation. In this study, we establish requirements for the appropriate choice of turbid model media and characterize mixtures of isosulfan blue as absorber and polystyrene beads as scatterer. For these model media, the independent determination of absorption and reduced scattering coefficients over large absorber and scatterer concentration ranges is demonstrated with a frequency domain photon density wave spectrometer employing intensity and phase measurements at various modulation frequencies.
urn:nbn:de:kobv:517-opus-13147
1314
Physical chemistry, chemical physics : PCCP ; a journal of European chemical societies. - ISSN 1463-9076. - 5 (2003), p. 5182 - 5187
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first published in:<br><a href="http://www.rsc.org/publishing/journals/CP/">Physical chemistry, chemical physics</a> : PCCP ; a journal of European chemical societies. - ISSN 1463-9076. - 5 (2003), S. 5182 - 5187<br>doi: <a href="http://dx.doi.org/10.1039/b308630e">10.1039/b308630e</a><br>
Reproduced by permission of the PCCP Owner Societies
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Oliver Reich
Hans-Gerd Löhmannsröben
Frank Schael
Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe
paper 026
Chemie und zugeordnete Wissenschaften
open_access
Institut für Chemie
Extern
Universität Potsdam
https://publishup.uni-potsdam.de/files/1208/Reich2003.pdf
19829
2000
2000
eng
article
1
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Near infrared diode laser spectroscopy of organic compounds in turbid aqueous solutions
Diffuse reflectance measurements and photon migration studies with near infrared (NIR) diode lasers were employed to elucidate experimental methods for determining absorption and scattering coefficients and species concentrations in highly scattering solutions. Applicability of theoretical approaches were established by investigating model systems with absorbing (e.g. ink, malachite green) and scattering (e.g. milk powder, caolinit) species in aqueous solution. While diffuse reflectance measurements practically requires calibration procedures, photon migration studies allow quantitative determination of absorption and scattering coefficients of turbid solutions consistent with absorptions coefficients obtained from Lambert-Beer's law. Furthermore, NIR absorption spectra of water, chlorinated hydrocarbons (chloroform, 1,2-dichloroethane, trichloroethene) and of various sugars ($alpha$-D-glucose, sucrose, maltose) are discussed. Spectral variations of NIR water absorption with temperature and solvents are exammined. Exemplary, NIR diode laser detection of water in acetone/water mixtures is performed.
0-9528666-1-7
allegro:1991-2014
10092589
Near infrared spectroscopy : proceedings of the 9th conference / Hrsg.: Anthony M. C. Davies ; Roberto Giangiacomo. - Chichester : NIR Publications, 2000. - ISBN 0-9528666-1-7. - S. 183 - 189
Frank Schael
Oliver Reich
Hans-Gerd Löhmannsröben
Institut für Chemie
Institut für Physikalische Chemie und Theoretische Chemie