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Copyright of European Poultry Science / Archiv für Geflügelkunde is the property of Verlag Eugen Ulmer and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This letter deals with an adaptationof the ac-electrogravimetry technique to extractseparately the dynamic propertiesof H+and water in Nafion nanometric thin films (averagethickness of 400 nm). An original theoretical approach was developedto extract the representative parameters from ac-electrogravimetrydata. The concentration change of the exchanged species and the diffusioncoefficient of the protons in a Nafion nanometric thin film (D= 0.5 × 10–6cm2s–1at 0.3 V vs SCE) were estimated for the first timeaccording to the applied potential. The conductivity value of Nafionthin films was calculated from the Nernst–Einstein equationusing diffusion coefficients and concentration values extracted from ac-electrogravimetry data. The calculated conductivity resultsagree well with the experimental proton conductivity values of Nafionthin films. [ABSTRACT FROM AUTHOR]

In this work, the global kinetics and the exchange ofprotons andfree solvent at the film/electrolyte interface were investigated whena PPy film doped with HPA (heteropolyanions) is polarized. The ionicand electronic transfers for the PPy-HPA system are fast because thedetermined values of the resistances are relatively low (a few ohms).Depending on the applied potential, the global kinetics is controlledby both the ionic and electronic transfers. The transport effectswere neglected here because the prepared films were very thin. Protonsplay an important role in charge compensation whatever the imposedpotential on the PPy-HPA film. This phenomenon results from the acidic–basicproperties of the SiMo12O404–reduced species. A small quantity of water was also shown to beinvolved in the film reaction process. [ABSTRACT FROM AUTHOR]