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Article Citation - WoS: 7Citation - Scopus: 7Characterization of Bi12sio20< Single Crystal: Understanding Structural and Thermal Properties(Springer Heidelberg, 2024) Altuntas, G.; Isik, M.; Gasanly, N. M.This study presents a thorough examination of the structural and thermal characteristics of Bi12SiO20 crystal. X-ray diffraction (XRD) analysis was employed to investigate the crystallographic structure, while scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) were utilized to ascertain morphological features and elemental composition, respectively. The XRD spectrum exhibited numerous peaks corresponding to the cubic crystalline structure. Thermal behavior was investigated through thermal gravimetric analysis (TGA), differential thermal analysis (DTA) and differential scanning calorimetry (DSC). Within the crystal, negligible weight loss was observed up to 750 degrees C, followed by weight loss processes occurring in the temperature ranges of 750-919 degrees C and above 919 degrees C. The 2% weight loss in the range of 750-919 degrees C was associated with the decomposition process, and the activation energy of this process was found to be 199 kJ/mol considering Coats-Redfern expression. A significant weight loss was observed in the region above 919 C-o and was associated with the decomposition of the Bi12SiO20 compound and/or the melting processes of the components of the Bi12SiO20 compound. Three endothermic peaks were observed in the DTA plot. Additionally, DSC measurements conducted under varied heating rates indicated endothermic crystallization process around 348 degrees C, with an activation energy of 522 kJ/mol determined through the Kissenger equation. These findings present valuable details regarding the crystal's structural configuration, morphological attributes, and decomposition/phase transitions, thereby illuminating its potential applications across various fields.Article Citation - WoS: 10Citation - Scopus: 11Effect of Heating Rate on Thermoluminescence Characteristics of Y2o3< Nanoparticles(Elsevier, 2019) Delice, S.; Isik, M.; Gasanly, N. M.The present paper reports the results of heating rate dependencies of thermoluminescence (TL) peaks observed for Y2O3 nanoparticles in the below room temperature region. TL glow curve presented six peaks around 62.5, 91.3, 114.5, 162.7, 196.0 and 214.9 K for heating rate of 0.4 K/s. The increase of heating rate resulted in increase in peak maximum temperature and decrease in peak maximum intensity as expected according to theoretical information. Peak maximum temperature-heating rate dependencies of observed peaks were analysed according to exponential dependency relation. Curve fit and initial rise methods were applied on thermally cleaned individual peaks and activation energies of associated trap centers, frequency factors and order of kinetics were obtained from the analyses. Activation energy values of the revealed trapping centers found from both methods were in good agreement with each other. Moreover, lattice parameters, crystalline size and micro-strain of nanoparticles were investigated by means of x-ray diffraction measurements.
