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This study concerns the application of artificial neural networks in oxidation kinetic analysis of ceramic nanocomposites. The oxidation of the Ti-Si-C ceramic nanocomposite in dry air was studied. The size of the nanoparticles was determined by scanning electron microscopy (SEM). The gaseous oxidation products were analysed by mass spectroscopy (MS) while the solid oxidation products by X-ray diffraction (XRD). The kinetic analysis of the oxidation was based on the Coats-Redfern equation. The kinetic models were identified for the consecutive stages and then the A and E parameters of the Arrhenius equations were evaluated. Artificial neural networks were used at each step of the kinetic calculations.

The factories processing natural phosphates and apatites in Poland release into the atmosphere considerable amounts of fluorine compounds. Fluoride is known to accumulate in the hard tissues of animals and humans. This paper describes the determination of fluoride in mandibles of deer in the years 1982 and 1990. In recent years, the establishments have restricted their output and modernized the technology of phosphate fertilizer production. The fluoride content in jaws has decreased, particularly in those animals having their habitat in the vicinity of the two factories.