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A fast and simple method for catalyst layer quality control on large surfaces has been introduced in the electrode production process for high temperature polymer electrolyte membrane fuel cells. Based on these results, the produced materials have been improved, resulting in the reduction of the frequency of defect occurrence and the improvement of performance, durability and reproducibility of the resulting membrane-electrode-assemblies. The obtained materials have been successfully operated at 0.4 A cm-2at 160 °C under wet reformate on the anode and compressed air on the cathode for over 750 h, giving 600 mV without any indication of degradation. One MEA was selected for post-mortem investigation by low-energy X-ray imaging. With this method, defects of the electrode were visualized and an indication for phosphoric acid loss identified. Further experiments are planned in order to verify the effect of the observed defects on the fuel cell behaviour.

The incubation of Krebs ascites tumor cells in medium with a high salt concentration resulted in a partial inhibition of nuclear RNA synthesis. The residual RNA polymerase activity in such nuclei was only slightly inhibited by low concentrations (50 nM) of α-amanitin. This finding suggested an inhibition of RNA polymerase II activity under conditions of medium hypertonicity. Indeed, RNA polymerase II, isolated from the nuclei of cells exposed to hypertonicity, revealed only half of the control activity. On the other hand, RNA polymerase I was not affected by hypertonicity. Moreover, chromatin fractions isolated from cells incubated in hypertonic or isotonic medium were equally template-active in RNA synthesis.