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Pyrrole was electrochemically polymerized on glassy carbon support in NaHS04 solutions under different conditions (method applied, concentration of monomer, concentration of the main solution, thickness of the film). These variables were used to study the preparation effect on the resulting properties, in particular on the potentiometric response of the PPy-HS04 electrodes. The electrodes were characterized by cyclic voltammetry, as well as by STM and AES techniques. Utilities of the polymer application as a sensor were studied by direct potentiometric measurements. The results obtained show that poly(pyrro1e) doped with bisulfate ions can serve as pH sensor, with the slope of EIpH curves approaching the theoretical value.

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The activity of Kand Al-promoted Fe/MgO catalyst for Fischer-Tropsch synthesis was measured under atmospheric pressure, with the aim to determine the promoter's influence on the catalyst selectivity, particularly in terms of olefins and isomers of lower hydrocarbons. The results have been correlated to the data of a previous study on the same catalyst, made under elevated pressure and designed for the alcohol production. It has been concluded that the promoting effect of K should be attributed to a geometric influence rather than to electronic promotion. The influence of Al promoter manifests itself like the "skin effect", resulting in suppression of adsorption of both CO and H2.