ZnO nanoparticles are prepared through hydrolysis and condensation of zinc acetate dihydrate by potassium hydroxide in alcoholic medium at low temperatures. Thermal gravimetric analysis (TGA) of the precursor is made in order to specify the temperature range over which the weight loss and thermal effect are significant. X-ray diffraction of the as-prepared specimens shows that the hexagonal (a=3.2459 Å,c=5.1999 Å) structure is the predominant crystallographic structure. According to Scherer’s formula, the average size of the nanoparticles is 22.4 ± 0.6 nm. The structural properties of the synthesized ZnO nanoparticles have been confirmed using the TEM micrographs. The optical energy gap of the ZnO nanoparticles, as obtained from applying Tauc’s equation, is equal to 3.52 eV, which is higher than that of the bulk material. Absorption peak of the as-prepared sample is 298 nm which is highly blue shifted as compared to the bulk (360 nm). Large optical energy gap and highly blue shifted absorption edge confirm that the prepared ZnO nanoparticle exhibits strong quantum confinement effect.

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The crystallization reaction of the Ge10Te35As55 glass under non‐isothermal conditions was studied. In the present work, a simple and approximation‐free method has been developed and applied to obtain the crystallization kinetics from only one DSC curve. A comparison between the experimental curve and that calculated using the JMA equation supports the validity of the proposed method. In the investigated glass, the obtained values of crystallization energy E, Avrami exponent n, and frequency factor K0 are (152.3 ± 1.9) kJ/mol, 2.0 ± 0.1, and (3.2 ± 1.1) 1011 s—1, respectively. One‐dimensional growth can be considered as the responsible crystallization mechanism.

Differential scanning calorimetry (DSC) results of Bi10 Se90 glass under non-isothermal conditions are reported. In the present work, the analyses have been focused on the endothermic peaks of the DSC curves. The models, used for calculation of the crystallization kinetics from the exothermic peaks, have been applied to obtain the pre-crystallization kinetics from the endothermic peaks. The activation energy of glass transition (Eg ), the Avrami index (n ) and the frequency factor (K 0 ) of the investigated glass are 186±0.2 kJ mol-1 , 2.08 and 2.5 × 1028 s-1 , respectively. The values obtained can be related to the kinetics of amorphous-crystalline transformations.