uu.seUppsala University Publications
Change search
ReferencesLink to record
Permanent link

Direct link
The dielectric response function determined by regular-singular-point analysis
Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Materials Science.
In: Phys. Rev. BArticle in journal (Refereed) Submitted
URN: urn:nbn:se:uu:diva-89905OAI: oai:DiVA.org:uu-89905DiVA: diva2:161755
Available from: 2002-05-15 Created: 2002-05-15Bibliographically approved
In thesis
1. Charged Particle Transport: As Information Source about Ion Conductors, Dielectric Materials, and Drug Delivery Systems
Open this publication in new window or tab >>Charged Particle Transport: As Information Source about Ion Conductors, Dielectric Materials, and Drug Delivery Systems
2002 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

This thesis treats charged particle transport, mostly in solid materials but also, to some extent, in aqueous media. Three major types of materials have been investigated; dielectric materials, ion conductors, and drug-delivery systems.

The frequency-dependent dielectric permittivity of sputtered amorphous thin film tantalum oxide (Ta2O5) has been determined by using impedance spectroscopy. A new interpolation formula has been derived, that interpolates between the two power-law regions at low and high frequencies usually observed in the dielectric spectrum. This formula is based on a regular-singular-point (RSP) analysis of the conduction process, and the power-laws in the dielectric spectrum are interpreted in terms of RSPs of the underlying rate equation for the corresponding polarization-current response function.

Lithium transport properties of Ta2O5 have been analyzed by using the galvanostatic intermittent titration technique and by isothermal transient ionic current measurements. Chemical and component diffusion coefficients for intercalated lithium have been extracted. Moreover, the ion conduction process has been analyzed theoretically, and expressions for transient ionic currents derived, both for single ion-conducting layers and for three-layered structures of ion conductors.

Electrical measurement techniques have also been applied to pharmaceutical systems. The alternating ionic current technique has been developed as a tool for determining the release of electrically charged drug substances in aqueous media. Tablets made of agglomerated micronized cellulose have been investigated, and sodium chloride has been used as a model drug. An attempt has been made to describe the combined drug dissolution and drug release processes in mathematical terms.

Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2002. 82 p.
Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1104-232X ; 725
Materials science, Materialvetenskap
National Category
Materials Engineering
Research subject
Engineering Science
urn:nbn:se:uu:diva-2103 (URN)91-554-5347-3 (ISBN)
Public defence
2002-06-07, the Hägg Lecture Hall at the Ångström Laboratory, Uppsala, 09:30
Available from: 2002-05-15 Created: 2002-05-15Bibliographically approved

Open Access in DiVA

No full text

By organisation
Department of Materials Science

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Total: 43 hits
ReferencesLink to record
Permanent link

Direct link