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In this paper was studied effect of temperature on the trans-resveratrol till to total degradation by UV-Vis spectrophotometry and FT-IR spectroscopy. Using statistical methods, it was observed that trans-resveratrol is unstable to higher temperatures than 100 �C, even in the absence of light. However, at temperatures up to 70 � C, resveratrol was found to be enough stable for time periods as short as 30 min. Pearson correlations of absorbance values at 304 nm (characteristic for trans-resveratrol) and 286 nm (characteristic for cis-resveratrol) shown that no conversion of trans-resveratrol to cis resveratrol is produced at elevated experimental temperatures.

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The study in vitro of the glass powders bioactivity was performed by soaking them in simulated body fluid for 3 to 21 days at a temperature of 37�C and pH = 7.20. The synthesis de novo of hydroxyapatite, post soaking was confirmed by Fourier Transform Infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The study of the antimicrobial activity was performed by microbiological examination on two strains of pathogenic bacteria involved in postoperative nosocomial infections.

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Chemiluminescence (CL) and differential scanning calorimetry (DSC) were applied for proving the copper ion migration processes occurring within the lowdensity polyethylene (LDPE) electrical insulator as a consequence of intimate contact. Thin LDPE slides of 0.5 mm thick were subjected to short-time thermal stress at temperatures between 80 and 120°C. Both CL and DSC kinetic parameters revealed the acceleration of posttreatment oxidation at elevated temperatures (170-200°C) in copper-contacting polymer as in respect to the cases when Cu was absent. It was revealed that the oxidation rate measured by CL was more than two times higher for the samples heated in the presence of Cu than in its absence, while the oxidation induction time from DSC was considerably lowered for the same samples. Elemental analysis data provided by atomic absorption spectroscopy and particle-induced X-ray emission techniques as well as SEM investigations confirmed the presence of copper within the samples subjected to thermal treatment when the polymer insulation was in contact with the metallic conductor. Chemiluminescence procedure has a remarkable sensitivity to detect the effect of copper in the polymer matrix even at low concentrations.