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Bi2O3–TeO2–CdO glasses' structural, thermal, optical, and gamma ray shielding behaviour were studied. Raman spectroscopy revealed that the glasses include BiO3, BiO6, TeO4, TeO3 units as well as CdO metal oxide clusters. The glasses lost just a small percentage of their original weight (less than 2%) on heating upto 800 °C, indicating that they can survive extreme heat without suffering any major changes to their structure or capabilities. The glass transition temperature (Tg) drops from 455 to 408 °C when Bi2O3 is added. The thermal profile of the glasses shows two exothermic peaks. As the Bi2O3 concentration in the samples rose, the indirect band gap energy dropped from 3.066 to 2.951 eV. With the use of the Phy-X program, the radiation shielding parameters have been calculated for the prepared glasses for energies ranging from 0.015 to 15 MeV. The linear attenuation coefficient (LAC) is high at 0.015 MeV (varied between 485.4 and 538.8 cm−1 for CTB4 glass, which is the glass with the largest percentage of Bi2O3, demonstrates the highest levels of LAC. The enhancement in the LAC due to the inclusion of Bi2O3 is observed in the prepared glasses. The enhancement in LAC is more pronounced at lower energies, especially below 0.03 MeV. From the effective atomic number data, increasing the amount of Bi2O3 in the glasses results in improved radiation shielding efficacy, particularly at lower energy. [ABSTRACT FROM AUTHOR]

The incorporation of Bi2O3 in the Bi2O3–BaO–V2O5 (BBV) glasses leads to higher density and molar volume. The average cross-link density ( n ¯ c ) increases from 4.2 to 4.8 cm−3 whereas the number of bonds per unit volume (nb) decreases from 4.974 × 1022 to 4.753 × 1022 as Bi2O3 is incorporated into the BBV glasses. The high values of elastic moduli indicate that the present glasses are resistant to any kind of the deformations when subjected to any kind of forces. The fractal bond connectivity (d) values indicate the 2D structure of the present glasses. Using Phy-X software, the radiation shielding capabilities were studied when Bi2O3 was used in place of BaO. The authors determined the linear attenuation coefficient (LAC) and discussed the change in this parameter due to the addition of Bi2O3 to the glasses. The glass with 20 mol% of Bi2O3 has the highest LAC and also has the highest effective atomic number. The minimum half value layer values was reported at 0.284 MeV and are equal to 1.220, 0.964 and 0.691 cm for the glasses with 5, 10 and 20 mol% of Bi2O3 respectively. The HVL increases with increasing energy, indicating that the samples are more efficient at shielding the low-energy radiation. At 0.347 MeV, the Zeff values are equal to 18.16, 21.09 and 26.05 for the samples with 5, 10 and 20 mol% of Bi2O3 respectively. The tenth value layer decreased with increasing density; for example, at 0.511 MeV, the layer decreased from 6.886 to 4.887 cm as the density increased from 3.6 to 4.281 g/cm3. The mean free path (MFP) was calculated and compared at 0.284 MeV. The authors found that BBV3 has the smallest MFP (0.997 cm) of the three examined glasses. [ABSTRACT FROM AUTHOR]

The fabrication process of PbO–Bi2O3–ZnO–B2O3(PBZB) glasses involved the application of a melt quenching technique. The glass samples were revealed through X-ray diffraction (XRD) analysis to be amorphous in nature. Fourier-transform infrared (FTIR) spectra, ranging from 4000 to 400 cm−1, exhibited peaks and bands indicating bending and stretching vibrations associated with the constituent groups in the glasses. The Raman spectra indicated that non-bridging oxygens (NBOs) formed with PbO’s incorporation into the network. To investigate the UV–Vis spectra of the glass, the Derivation of Absorption Spectrum Fitting (DASF) method was employed. This analysis predicted a decrease in energy band gap values, which was attributed to the increased presence of NBOs within the glass network. The prepared glasses’ radiation-shielding properties were reported using Phy-X software in the range of 0.284–1.333 MeV, where it was found that the mass attenuation coefficient (MAC) follows the order of PBZB1 < PBZB2 < PBZB3 < PBZB4, which means a positive correlation of the samples’ MAC with the glasses’ PbO content, or an inverse correlation with the glasses’ B2O3 content. Thus, the sample characterized by the highest content of PbO, or the least B2O3 content, has the greatest radiation shielding ability. The ratio between the tenth value layer for the PBZB1 and PBZB4 samples was estimated, with the results demonstrating the ratio to be higher than one, thus indicating that PBZB1’s TVL is always greater than PBZB4’s TVL. From the ratio between the TVL, we found that the addition of PbO causes a reduction in the thickness of the glass that is needed to attenuate the incoming photons. The PBZB4 sample (which contains 70 mol% of PbO) has the greatest advantage over the other materials in the glass system at lower and higher energies, while having a slightly reduced advantage at medium energies. PBZB4 possesses the lowest HVL value, thus qualify as the best shielding material. [ABSTRACT FROM AUTHOR]

In this study, we investigated the impact of micro- and nano-sized barium oxide addition on the radiation-shielding properties of red clay tiles mixed with waste marble and different sizes of BaO (micro- or nanoparticles) for comparative analysis. The linear attenuation coefficients (LAC) of the prepared samples were measured using an HPGe detector between 0.060 and 1.333 MeV. Moreover, a comparison was made between the experimental micro-composites and values obtained by Phy-X software. The results revealed that the red clay/waste marble tile composites doped with nano-sized BaO demonstrated superior radiation-shielding properties compared to those doped with micro-sized BaO. At 1.33 MeV, WR-20mBaO (containing 20 wt % micro-sized BaO) and WR-20nBaO (containing 20 wt % nano-sized BaO) exhibited HVL values of 4.75 cm and 4.25 cm, respectively. The lower HVL value of WR-20nBaO indicates superior radiation-shielding performance, highlighting the potential benefits of using nano-sized BaO as a radiation-shielding additive. Our findings also demonstrated that increasing the amount of BaO deposited onto red clay mixed-waste marble resulted in improved radiation-shielding properties. Our study demonstrates that adjusting the concentration of BaO is a viable strategy for enhancing the radiation attenuation properties of red clay tiles. In addition, the addition of waste marble to the tiles enhances its mechanical properties, and it is also positively recycled in community service. [ABSTRACT FROM AUTHOR]

This paper reports on the structural, optical and luminescence studies of Dy3+–Eu3+ co-doped glass ceramics that are obtained via thermal treatment method. The initial confirmation on glass ceramics with the formation of NaBSiO4 crystalline phase was made through XRD study. The FTIR study showed the vibrations of network formers (B2O3, SiO2) and other functional groups. The quantity of non-bridging oxygens (NBOs) are increased in the glass ceramics with increase in annealing temperature. The absorption spectra (UV–visible-NIR) showed the possible transitions of Dy3+ and Eu3+ ions in the glass ceramics. A red-shift in the absorption band-edge and reduction in the optical band gap values were obtained for glass ceramics owing to their heating temperatures. Photoluminescence studies showed the excitations of Dy3+ and Eu3+ ions under 575 nm and 613 nm emission wavelengths. The obtained NaBSiO4 crystalline phase in the glass ceramics has enhanced the luminescence intensity, and lifetimes of Dy3+ and Eu3+ ions compared to unheated precursor glass when excited under 350 nm and 393 nm. Color chromaticity diagram and correlated color temperature (CCT) values showed a shift in the color of light from warm white of precursor glass to neutral white of glass ceramics. The overall results justify the possibility of considering the Dy3+-Eu3+ co-doped glass ceramics as efficient materials for solid-state lighting applications like W-LEDs. [ABSTRACT FROM AUTHOR]

Cobalt-doped titania nanocomposites were fabricated to be utilized for radiation shielding aims. The chemical composition of the composites was measured using the energy-dispersive X-ray spectrometer. Moreover, the structure of the composites was evaluated using the X-ray diffractometer, and the morphology of the fabricated composites was presented using the scanning electron microscope. Furthermore, the γ-ray shielding properties were estimated using the Monte Carlo simulation between 0.059 and 2.506 MeV. The linear attenuation coefficient of the fabricated composites decreased by factors of 93% for all samples by raising the incident γ-energy between 0.059 and 2.506 MeV. Moreover, the partial replacement of the Ti4+ by Co3+ slightly enhanced the linear attenuation coefficient from 0.607 to 0.630 cm−1 when the Co3+ increased from 0 to 3.7 wt%. The improvement in the linear attenuation coefficient causes an enhancement in other radiation shielding properties. [ABSTRACT FROM AUTHOR]

The primary objective to develop the high-density glasses have been fulfilled by replacing the TeO2 with Bi2O3 in the Bi2O3–TeO2–CdO glass system in the present work. Samples’ density (ρ) is large enough, ranging from 5.636 g/cm3 to 5.788 g/cm3. Due to the expansion of the network the molar volume (Vm) and oxygen molar volume increases and the oxygen packing density decreases. The elastic characteristics of the resulting glasses diminished with increasing Bi2O3 concentrations in the network structure. The radiation shielding parameters were presented between 0.122 and 1.458 MeV. The transmission factor (TF) for the glasses with thickness of 0.25 cm is around 50% at 0.245 MeV, while for the same glasses with thickness of 0.5 cm, we found that the TF is varied between 20 and 25%. The TF reaches a minimum of about 4–6% when the thickness is 1 cm. The TF data demonstrated that introducing more Bi2O3 into the samples leads to an improvement in the radiation shielding performance of the glasses. The effective atomic number (Zeff) values at 0.245 MeV are equal to 61.74, 63.03, 64.16, and 65.18 for A1–A4, respectively. The average HVL ( HVL ¯ ) results showed that a thin sample less than 0.4 cm thick can be used to shield photons with energies between 0.245 and 0.344 MeV, while a shield with thickness 0.65 to 0.70 cm is needed to attenuate photons with energies between 0.411 and 0.444 MeV. [ABSTRACT FROM AUTHOR]

Development of next-generation photonic device necessitates employing vitreous materials with high optical nonlinearities and low optical limiting thresholds. Additionally, the high nonlinear photonic glasses are suitable for nuclear radiation shielding applications. Herein, the borate-based glass specimens bearing significant amounts of heavy metal oxides (Bi2O3 and PbO) activated with various quantities of Eu2O3 have been explored for optical limiting, nonlinear photonic, and nuclear radiation shielding applications. Efficacy of Eu2O3 content on functional features has been assessed and discussed the outcomes in detail. The open aperture Z-scan results unveiled the enhancement in two-photon absorption coefficient and reduction in optical limiting threshold with Eu2O3 amount in the glass composition. Further, certain fundamental attenuation factors such as mass attenuation and linear attenuation coefficients were estimated utilizing Phy–X software in the energy ranges between 0.284 and 2.506 MeV. The mass attenuation and the linear attenuation coefficients were found to improve with the inclusion of more and more Eu2O3 in the glass compositions. The outcomes of the study clearly revealed that the high Eu2O3 activated lanthanum heavy metal borate glasses are productive in optical limiting, nonlinear optical, and gamma radiation shielding strategies to cutoff the high energy electromagnetic and nuclear radiations. The comparative study further validates that the La2O3–Bi2O3–B2O3–Eu2O3 glasses are more advantageous than La2O3–PbO–B2O3–Eu2O3 glasses. [ABSTRACT FROM AUTHOR]

We developed new composites for photons shielding applications. The composite were prepared with epoxy resin, red clay and bismuth oxide nanoparticles (Bi2O3 NPs). In order to establish which ratio of red clay to Bi2O3 NPs provides the best shielding capabilities, several different ratios of red clay to Bi2O3 NPs were tested. The transmission factor (TF) was calculated for two different thicknesses of each sample. From the TF data, we found that epoxy resin materials have a high attenuation capacity at low energy. For ERB-10 sample (40%Epoxy + 50% Red clay + 10% Bi2O3 NPs), the TF values are 52.3% and 14.3% for thicknesses of 0.5 and 1.5 cm (at 0.06 MeV). The composite which contains the maximum amount of Bi2O3 nanoparticles (40%Epoxy + 50% Red clay + 10% Bi2O3 NPs, coded as ERB-30) has lower TF than the other composites. The TF data demonstrated that ERB-30 is capable of producing more effective attenuation from gamma rays. We also determined the linear attenuation coefficient (LAC) for the prepared composites and we found that the LAC increases for a given energy in proportion to the Bi2O3 NPs ratio. For the ERB-0 (free Bi2O3 NPs), the LAC at 0.662 MeV is 0.143 cm−1, and it increases to 0.805 cm−1 when 10% of Bi2O3 NPs is added to the epoxy resin composite. The half value layer (HVL) results showed that the thickness necessary to shield that photons to its half intensity can be significantly lowered by increasing the weight fraction of the Bi2O3 NPs in the epoxy resin composite from 0 to 30%. The HVL for ERB-20 and ERB-30 were compared with other materials such as (Epoxy as a matrix material and Al2O3, Fe2O3, MgO and ZrO2 as filler oxides in the matrix at 0.662 MeV. The HVL values for ERB-20 and ERB-30 are 4.385 and 3.988 cm and this is lower than all the selected epoxy polymers. [ABSTRACT FROM AUTHOR]

Owing to their low dielectric loss and high permittivity values, dielectric ceramics have garnered a lot of interest from the scientific and industrial sectors. These properties allow for their downsizing and use in a variety of electronic circuits. This present work focuses on the impact of the substitution of W6+ with Mo6+ on the structural and dielectric features of the crystalline phases in a similar TTB structure within the Ba0.54Na0.46Nb1.29W(0.37−x)MoxO5 system, with 0 ≤ x ≤ 0.33 mol%. These crystalline phases were elaborated using the conventional solid-state reaction method and analyzed with XRD, Raman, and dielectric techniques. The Rietveld refinement method showed that all these phases are characterized by tetragonal structure and the P4bm space group. The Raman spectra corresponded well to a TTB-like structure, and all the bands were assigned. The dielectric measurements of the prepared ceramic samples facilitated the determination of their phase transition temperature (Tc) and the dielectric responses. This investigation focused on determining dielectric permittivity (ε′) and its correlation with increases in MoO3 content in the ceramic structure. [ABSTRACT FROM AUTHOR]

Three different samples were synthesized based on polyepoxide resin, a solidifying agent, and a Bi2O3 doping compound. The polyepoxide resin and solidifying agent were added in a 2:1 ratio by weight and the Bi2O3 compound was added in ratios of 0, 5, and 10 wt. %. The density of the synthesized composites was measured using an MH-300A densimeter with an uncertainty in measurement of 0.001 g/cm3. The measurements showed that the density of the fabricated composite varied from 1.103 g/cm3 to 1.20 g/cm3 when the reinforcing Bi2O3 compound was raised from 0 wt. % to 10 wt. %. Furthermore, the γ-ray shielding parameters were evaluated based on the simulated mean track length of γ-photons inside the synthesized composites using MCNP-5 code. The simulated results show an enhancement in the shielding parameter when increasing the Bi2O3 concentration, where the linear attenuation coefficient values increased from 0.101 cm−1 to 0.118 cm−1 as the Bi2O3 concentration increased from 0 to 10 wt. %. The increase in the LAC has a positive effect on the other shielding properties. [ABSTRACT FROM AUTHOR]

Rare earth (RE)–doped glasses with high quantum efficiency and strong photoluminescence (PL) characteristics are essential for next generation photonic and optoelectronic devices. To attain strong PL emission and related attributes of Er3+-doped in glass system, the silver nanoparticles (NPs) were embedded. UV-Vis absorption and microscopic measurements divulged the existence of metallic silver NPs. The PL emission of Er3+-doped in titled glasses was improved in visible and infrared spectral ranges as AgNO3 concentration escalated to higher level. In addition, the quantum efficiency also enhanced as the AgNO3 doping level escalated to a higher level. The enhancements in PL emission intensity and quantum efficiency were ascribed to the local field induced by surface plasmons of Ag NPs. The outcomes suggest that the high concentration of Ag NPs routed in Er3+-doped glass system is useful in fabricating the optical amplifiers and solid-state lasers. [ABSTRACT FROM AUTHOR]