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Thermal effects in polycarbonate (PC) induced by lanthanide oxide nanoparticles (NPs) dispersed by blending were studied using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). DSC data proved the occurrence of solvent‐induced crystallization of polymer doped with cerium oxide (ceria). TGA was performed to predict PC flammability properties in composites with 5–15 wt % ceria NPs at various heating rates. Decomposition was represented by first‐order reactions and the Arrhenius equation. A model was formulated for thin samples subject to uniform heat irradiation, which is based on PC softening and decomposition into several products. This is an attempt to predict composite film burning behavior assuming constant heat transmission to samples. [ABSTRACT FROM AUTHOR]

The enhanced stability of Co nanocrystals (NCs) when they are highly ordered at both nanometer and micrometer scales is reported. For the first time, it is shown that both the crystalline structure of Co nanoparticles (NPs) and their 2D hexagonal organization have a significant impact on the oxidation process rate enabling to produce various types of nanostructures including core-shell NPs. The Co core can be either polycrystalline or hexagonal close-packed (hcp) single-crystalline, whereas the oxide shell is composed either of CoO or of the spinel structrure Co3O4. The present results are evidenced through a careful high-resolution transmission electron microscopy (HRTEM) study and are highly reproducible. [ABSTRACT FROM AUTHOR]

Objectives: To get insight in the mechanism of exercise-induced ST-segment elevation (STE) in patients with Q/QS waves at the electrocardiogram (ECG). Methods: We performed exercise stress test in 13 patients with anterior acute myocardial infarction treated by successful primary percutaneous coronary intervention (PCI). Results: Compared to rest, an additional STE 1 mm in one or more precordial ECG leads during exercise occurred in nine patients (69%), in the absence of symptoms. Conclusions: In acute myocardial infarction (MI) patients, treated by primary PCI and showing optimal coronary blood flow restoration at angiography, STE can still be induced by exercise in Q/QS wave ECG leads. This finding lends further support to the theory that exercise-induced STE in this clinical context is unlikely to represent by itself transient myocardial ischemia or viability. [ABSTRACT FROM AUTHOR]