Eu3+-doped alkali calcium alumino phosphate oxide (OD) and oxyfluoride (OF) glasses were successfully fabricated using the conventional melt-quenching route. Comparative analyses were performed between the two systems to evaluate their physical, optical, photoluminescence and X-ray induced luminescence properties. The OD glass exhibited higher density and refractive index compared to the OF glass, indicating a more compact glass network. However, the molar volume of the OD was lower than that of the OF due to the larger free volume generated by fluoride incorporation. Based on the absorption spectra, both glass systems exhibited almost identical spectral profiles with minor variations in absorbance intensity. In the photoluminescence study, both glass systems exhibited strong red emission at around 612 nm (5D0→7F2 transition) under 394 nm excitation. The OF glass exhibited a higher emission intensity than the OD glass, primarily due to the lower concentration of hydroxyl groups that act as non-radiative quenching centers. Both glass systems exhibited a reddish-orange emission, in good agreement with the CIE 1931 chromaticity coordinates. The X-ray–induced luminescence exhibited a spectral pattern comparable to that of photoluminescence, while differing in excitation source and luminescence mechanism. The integrated scintillation efficiencies of both glass systems were derived from the peak areas of their X-ray–induced luminescence spectra and compared with that of a Bi4Ge3O12 (BGO) crystal to evaluate their relative scintillation performance. The glasses were successfully imaged under X-ray excitation, confirming their strong potential as optical probes for medical imaging applications.
The use of rice husk ash (RHA) an agricultural waste not only reduces environmental impact but also contributes to the development of circular economy. The exploration of RHA as a renewable energy resource has enormous potential in promoting sustainable development. The glass composition in this work incorporates silica from RHA derived through sintering processes. A glass system with the composition (60-x)B2O3-xBi2O3-20ZnO-20RHA (x = 25, 35, 45 mol%) was prepared through heavy metal oxide (Bi2O3) substitution using the melt quenching technique. X-ray diffraction (XRD) was used to confirm the amorphous nature of the glasses. The BZRBi25, BZRBi35, and BZRBi45 glass samples exhibit appropriate transmittance in the visible region at a consistent thickness of 1 mm. Fourier transform infrared (FTIR) spectroscopy was used to identify the vibrational modes and their corresponding functional groups. The replacement of B2O3 with Bi2O3 in the prepared glasses resulted in an increase in the density from 4.061 to 4.843 g/cm3. To confirm the accuracy of the values over an energy range of 0.015-15.0 MeV, a comparative analysis was carried out for the gamma ray shielding parameters, namely, the mass attenuation coefficients (mu m), effective atomic number (Zeff), and effective electron density (Neff) estimated by WinXCom software (theoretical), Compton scattering (experimental), and Particle and Heavy Ion Transport Code System (PHITS-simulation). In comparison to standard shielding materials, the examined glasses exhibit reduced half value layer (HVL) values. At an energy of 0.662 MeV, the lead equivalent thickness (Delta eq) of the glass samples increases with increasing concentration of Bi2O3. Additionally, the total mass stopping power (TMSP) and projected range (PR) have been determined for proton particles (H+) and alpha particles (He+2), respectively. A PHITS Monte Carlo simulation was performed at 0.662 MeV to calculate absorbed dose and effective dose rate in a phantom with and without shielding glass. The results indicate that the incorporation of RHA into the eco-friendly radiation shielding glasses has the potential to be an effective replacement for protection against gamma, proton, and alpha radiations.
This study explores the influence of barium oxide (BaO) content on the physical, optical, and gamma-ray shielding properties of borosilicate glass. Glass samples containing 0 to 40 mol% BaO were prepared via the melt-quenching technique. Their physical and optical properties were experimentally characterized using the Archimedes' principle for density measurement and transmittance (%T) evaluation. The radiation shielding parameters were evaluated using a combination of experimental measurements, Monte Carlo simulations (PHITS), and theoretical calculations (WinXCom). The shielding properties of the glasses were examined over a wide energy range of 0.015 MeV-15 MeV theoretically and compared with the simulation results. Experimentally, 133Ba, 137Cs, and 60Co were used as standard sources to generate monoenergetic photons covering an energy range of 0.356 MeV to 1.332 MeV. The findings indicate that increasing BaO concentration enhances the density, attenuation values and EABF, particularly at low to intermediate photon energies. The experimental results revealed that the highest radiation shielding performance was observed at the low energy of 0.356 MeV, where the values of mu, Zeff, Neff, HVL, and Pb-equivalent thickness were found to be 0.35 cm-1, 14.94 e-/atom, 3.26 x 1023 e-/g, 1.92 cm, and 0.35 mm, respectively. BaO 20 glass was fabricated into a large-scale transparent glass sheet to demonstrate its feasibility for use as an observation window from outside radiation-controlled rooms, aiming to enhance environmental safety in future applications.
The CsI(Tl) and CsI(Tl:xSr) were synthesized and grown using the Bridgman technique. The present work aims to study the effect of Sr co-doping on the scintillation performance of CsI(Tl) crystals to determine the potential applications in X-ray imaging systems. In the X-ray induced luminescence study at room temperature, emission spectra exhibit features characteristic of intrinsic CsI luminescence and Tl+ center emission. The presence of the co-dopant has no significant effect on the spectral characteristics. The scintillation performance study, including light output, energy resolution, and scintillation decay profile, was characterized by irradiating the grown crystals under a137Cs gamma-ray source. It was found that Sr co-doping in CsI(Tl) crystals resulted in a degradation of both light output and energy resolution, with an approximate 12% reduction in light output compared to the single-doped CsI(Tl) crystal. However, a suppression of afterglow was observed in the co-doped crystals, showing a reduction of approximately 1.5% relative to the single-doped crystal. This finding suggests that Sr can effectively suppress afterglow in CsI(Tl) crystal. We investigated X-ray imaging using diagnostic X-ray and Synchrotron X-ray as a source to study the performance of the grown crystal for practical applications. This study represents the first investigation of X-ray imaging obtained by Sr co-doped CsI(Tl) crystal. The above experiment results suggest that the developed crystal is a promising candidate for the X-ray imaging system, especially medical imaging and synchrotron X-ray computed tomography applications.
Freshwater scarcity has intensified the demand for sustainable desalination technologies capable of utilizing lowgrade thermal energy. Solar-driven vacuum desalination systems represent a promising approach for decentralized freshwater production, as evaporation can be enhanced under reduced-pressure conditions at relatively low temperatures. This study aims to experimentally investigate and optimize the performance of a solar-driven vacuum desalination system and to develop a predictive model for system behavior. A laboratory-scale system was evaluated using Response Surface Methodology based on Box-Behnken Design (RSM-BBD), considering cycle time, cooling water flow rate, and heat source temperature as key operating variables. In addition, an Adaptive Neuro-Fuzzy Inference System (ANFIS) model was developed to capture the nonlinear relationship between operating parameters and freshwater production. The results indicate that heat source temperature is the dominant parameter controlling system productivity. Optimal operating conditions were identified at a cycle time of 20 min, cooling water flow rate of 11.5 L center dot min(-1), and heat source temperature of 70 degrees C, yielding a maximum freshwater production rate of 0.1441 L center dot min(-1) with salt rejection above 99%. The ANFIS model demonstrated good predictive accuracy, with an RMSE of 0.0177 and a coefficient of determination (R-2) of 0.88. These findings highlight the effectiveness of reduced-pressure evaporation for enhancing low-temperature desalination performance. The proposed hybrid RSM-ANFIS framework provides a reliable approach for optimizing vacuum desalination systems and supports their application in renewable and waste heat-driven freshwater production.
