SnO-based sensors doped with palladium (0, 1, 3, 5 and 7%) were prepared by the wet impregnation method. To characterize them, the techniques ofinfrared spectroscopy with Fourier transform (FTIR), adsorption and desorption of N2 (BET), XRD, scanning electron microscopy (SEM), and X-ray dispersive energy (EDX) spectroscopy were used. The sensors were evaluated with ethanol to form, together with two commercial sensors, an electronic nose (E-nose) that could detect volatile aroma components in Peruvian wines. The results were interpreted through principal component analysis (PCA) to find a technique that complemented the information collected by gas chromatography (GC) and liquid chromatography (HPLC), and by comparing the PCAs obtained from GC, and HPLC with those resulting from E-nose. It was found that the latter classified the samples better. It was possible to differentiate both wines...

Catalysts based on Ni-Fe-a with a catalyst ratio of a = Ni/(Ni + Fe) (a = 0.8 and 0.9) supported on γ-Al2O3 were prepared by coprecipitation-deposition and tested for the oxidative dehydrogenation (ODH) of ethane. The bulk mixed samples exhibited 30% greater selectivity toward ethylene than did the corresponding simple oxide NiO. Meanwhile, the most selective sample, NiFe-0.9/γ-Al2O3, achieved a maximum of 94% at 400 °C. The remarkable selectivity of NiFe-0.9/γ-Al2O3 was attributed to the partial substitution effect of Ni2+ by Fe3+, thus allowing those catalysts to form oxygen sites that are specific for the partial oxidation of ethane to ethylene. Some additional factors that could have contributed to ethylene selectivity were the formation of low-reducibility species with controlled particle size, a better dispersion of the active phase over the support and the synergy of Fe3+ with...