TY  - JOUR
A1  - Bressel, Lena
A1  - Reich, Oliver
T1  - Theoretical and experimental study of the diffuse transmission of light through highly concentrated absorbing and scattering materials Part I: Monte-Carlo simulations
JF  - Journal of quantitative spectroscopy & radiative transfer
N2  - In many technical materials and commercial products like sunscreen or paint high particle and absorber concentrations are present. An important parameter for slabs of these materials is the diffuse transmission of light, which quantifies the total amount of directly and diffusely transmitted light. Due to the high content of scattering particles not only multiple scattering but also additional dependent scattering occurs. Hence, simple analytical models cannot be applied to calculate the diffuse transmission. In this work a Monte-Carlo program for the calculation of the diffuse transmission of light through dispersions in slab-like geometry containing high concentrations of scattering particles and absorbers is presented and discussed in detail. Mie theory is applied for the calculation of the scattering properties of the samples. Additionally, dependent scattering is considered in two different models, the well-known hard sphere model in the Percus-Yevick approximation (HSPYA) and the Yukawa model in the Mean Spherical Approximation (YMSA). Comparative experiments will show the accurateness of the program as well as its applicability to real samples [1]. (C) 2014 Elsevier Ltd. All rights reserved.
KW  - Monte-Carlo simulations
KW  - Multiple light scattering
KW  - Dependent light scattering
KW  - Hard sphere model in the Percus-Yevick Approximation
KW  - Yukawa model in the Mean Spherical Approximation
KW  - Polymer dispersions
Y1  - 2014
U6  - https://doi.org/10.1016/j.jqsrt.2014.01.007
SN  - 0022-4073
SN  - 1879-1352
VL  - 146
SP  - 190
EP  - 198
PB  - Elsevier
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Bressel, Lena
A1  - Hass, Roland
A1  - Reich, O.
T1  - Particle sizing in highly turbid dispersions by Photon Density Wave
 spectroscopy
JF  - JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
N2  - Photon Density Wave (PDW) spectroscopy is presented as a fascinating technology for the independent determination of scattering (mu(s)’ and absorption (ita) properties of highly turbid liquid dispersions. The theory is reviewed introducing new expressions for the PDW coefficients k(I) and k(Phi). Furthermore, two models for dependent scattering, namely the hard sphere model in the Percus-Yevick Approximation (HSPYA) and the Yukawa model in the Mean Spherical Approximation (YMSA), are experimentally examined. On the basis of the HSPYA particle sizing is feasible in dispersions of high ionic strength. It is furthermore shown that in dialyzed dispersions or in technical copolymers with high particle charge only the YMSA allows for correct dilution-free particle sizing. (C) 2013 Elsevier Ltd. All rights reserved.
KW  - Photon Density Wave spectroscopy
KW  - Multiple light scattering
KW  - Dependent light scattering
KW  - Percus-Yevick model
KW  - Yukawa model
KW  - Particle sizing
KW  - Polymer dispersions
Y1  - 2013
U6  - https://doi.org/10.1016/j.jqsrt.2012.11.031
SN  - 0022-4073
VL  - 126
IS  - 1
SP  - 122
EP  - 129
PB  - PERGAMON-ELSEVIER SCIENCE LTD
CY  - OXFORD
ER  -