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This study focuses on the influence of low-concentration additions of NiCl2 on the overall properties of lead arseborate oxide glasses. In this regard, small amounts, in grams, of NiCl2 were added, separately, to the main constituents of the lead-arseboarte glass, according to the chemical formula [23 wt% B2O3–11 wt.% Na2O–20 wt. CaO–23 wt.% PbO–23 wt.% As2O3] % + x NiCl2, where x = 0.25, 0.5, 0.75, and 1 g, to prepare a glass series of four samples using the fast quenching technique. The structural and optical characterizations of the prepared samples have been described based on X-ray diffraction (XRD) measurements, Fourier transform infrared charts (FTIR), and UV–Vis spectra. The X-ray diffraction (XRD) patterns did not contain any crystalline peaks but only two broad humps which revealed that all samples possess short-range order structures. At the same time, the FTIR charts showed different structural units. The UV–Vis spectra demonstrated that the absorption edge spectra changed to a higher wavelength with an increase in NiCl2 dopants, accompanied by a drop in optical transmittance, particularly in the visible range. As the NiCl2 dopants increased, the values of the optical energy gaps reduced while the mass attenuation remained constant, and the effective atomic number, bulk density, microhardness, absorption index, and characteristic relaxation time increased. Regardless of sample thickness, a novel methodology has been proposed to determine both the optical band gaps and the optical loss. The novel method and the widely used one (Tauc relation) demonstrated excellent agreement. The results suggest the NiCl2-rich sample is a primary material for radiation shielding applications as a carrier for radioactive sources and preserving them, or for preserving radioactive waste and high-reflection and UV-blocking glass coating. [ABSTRACT FROM AUTHOR]

This study focuses on how the chemical makeup of the glass' basic components affects the glass' structure and optical characteristics. Four glass samples have been created for this purpose using the chemical formula; 94 mol% Na2B4O7—(6-x) mol% CeO2 – x mol% Ce(NO3)3, where 0 ≤ x ≤ 6. The Ce cations in this formula have two separate chemical sources, CeO2 and Ce(NO3)3, with CeO2 eventually being replaced by Ce(NO3)3. The standard melt-quenching technique was used to prepare the studied glasses. While X-ray direction (XRD), differential scanning calorimetry (DSC), and UV–vis were used for the structural and optical characterizations. XRD patterns revealed the short-range order glass networks for the prepared samples, while DSC thermograms showed that when CeO2 was replaced with Ce(NO3)3, the glass transition temperature (Tg) decreased, causing the glass stability to improve. The optical characterization resulted in the finding that when CeO2 was replaced with Ce(NO3)3, the Urbach's energy increased with a decrease in bandgap energies, which reflects an increase in the glass homogeneity. Finally, the results may imply that Ce(NO3)3-based glasses can be proposed for usage in applications for UV blockers, radiation shielding, light attenuation, and n-type semiconductors. [ABSTRACT FROM AUTHOR]

This study involves the investigation of the effect of the replacement of B2O3 with La2O3 on the properties of the multi-component lead Borovanadate glass. Five samples were prepared using the fast-quenching method according to the chemical formula (43-x) mole % B2O3 - x mole % La2O3- 10 mol % V2O5-12.5 mol % CaO-12.5 mol % Li2O -22 mol %PbO, where x = 0, 1, 2, 3, and 5 mol %. The amorphous character of the synthesized samples was confirmed via Fourier transform infrared and X-ray diffraction. XRD patterns suggest a lack of long-range organized crystalline structure, but FTIR reveals various structural unit blocks. On the other side, the increment of La2O3 content caused a proportional increase in the glasses' bulk density and molar volume. UV analysis revealed that the sample with 5 mol % La2O3 had superior absorption properties compared to the other samples. All the samples were found to be effective in transmitting light within the energy range of 3.43–4.07 eV, with the La2O3-free sample demonstrating the highest level of light transmission among all the samples. The radiation shielding characteristics of the synthesized glasses were analyzed. The theoretical predictions for the mass attenuation coefficients using WinXCom agreed well with the measured values, providing validation for both the software and the experimental techniques used. This investigation found that La2O3 concentration influenced the linear attenuation coefficient (LAC) at a defined energy level, with higher La2O3 resulting in higher LAC values. The study also showed that lower energy levels had better linear attenuation compared to higher ones. [ABSTRACT FROM AUTHOR]

This qualitative work focuses on a comparison between the roles of a lanthanide oxide CeO2 and a transition metal oxide Cu2O3 when introduced to sodium borate glass. Two glass samples have been prepared using the fast quenching method, where two types of glasses were obtained: (i) copper-free/cerium-rich sodium borate glass, and (ii) cerium-free/copper-rich sodium borate glass. XRD patterns indicated the amorphous nature of the prepared samples regardless of the dopant type, either CeO2 or Cu2O3. The optical characterization showed that the CeO2-doped and Cu2O3-doped samples have the same Urbach energy, resonance frequency, and damping factor. But differ in the values of the transmittance, reflectance, plasmon frequency, and the concentration of the free charge carriers. The acquired results may recommend CeO2-doped borate glasses as major components in the field of data transfer materials, such as those used in the manufacture of computer chips, whereas Cu2O3-doped borate glasses were proposed for applications involving) attenuation of the low energy light (UV–VIS–NIR). [ABSTRACT FROM AUTHOR]

This work aims to prepare modified glassy barriers of the composition (70 − x) mol% B2O3 + 20 mol% Na2O + 10 mol% BaO + x mol% La2O3 for use as radiation shielding materials. The cooling method has been considered for the sample's preparation process. The structural properties were investigated using density and Infrared Spectroscopy. The hardness of the prepared glasses was studied. The optical transmittance and absorbance of the prepared glasses was measured using optical spectra measurements. The prepared samples were exposed to a parallel beam of gamma rays emitted from different radioactive sources. Moreover, the shielding properties were evaluated experimentally and theoretically. The resulting value of the proposed programs is largely in line with the experimental values. The results prove that the studied glass has a largely shielding behavior for gamma rays by increasing lanthanum and vice versa for neutrons. In addition, it has been observed that the absorbance of glass samples and hardness values increase with increasing lanthanum content. [ABSTRACT FROM AUTHOR]