Provider: ingentaconnect
Database: ingentaconnect
Content: application/x-research-info-systems
TY - ABST
AU - Tuononen, Heikki
AU - Fukunaga, Kaori
AU - Kuosmanen, Marko
AU - Ketolainen, Jarkko
AU - Peiponen, Kai-Erik
TI - Wiener Bounds for Complex Permittivity in Terahertz Spectroscopy: Case Study of Two-Phase Pharmaceutical Tablets
JO - Applied Spectroscopy
PY - 2010-01-01T00:00:00///
VL - 64
IS - 1
SP - 127
EP - 131
KW - PHARMACEUTICAL TABLET
KW - TERAHERTZ SPECTROSCOPY
KW - COMPLEX PERMITTIVITY
N2 - The terahertz measurement technique has become popular in the field of pharmaceutical technology for tablet quality inspection. Spectral data obtained from the tablets is based on the utilization of Fresnel's formulas for an ideal slab. However, a tablet is a porous medium. Hence, in
the THz gap one has to assume that a tablet constitutes at least an effective medium if the Fresnel theory is applied in quantitative permittivity spectra analysis. Hence, it is suggested that one should consider instead of the permittivity of homogeneous media the concept of effective permittivity
in the THz terminology of porous tablets. Usually the fill factor of a component of a tablet is known but not the detailed bulk structure. Nevertheless, it is possible to estimate the complex effective permittivity of a tablet with the aid of so-called Wiener bounds. The idea of this article
is to present a modification of Wiener bounds applied to the estimation of the real and imaginary part of the permittivity of the pure component of a tablet. As an example, the effective complex permittivity of a starch acetate tablet is considered.
UR - http://www.ingentaconnect.com/content/sas/sas/2010/00000064/00000001/art00024
M3 - doi:10.1366/000370210792966170
UR - http://dx.doi.org/10.1366/000370210792966170
ER -