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The impact of the insertion of Pb2+ ions into the Li2O–BaO–B2O3 based glass matrix has been investigated. The Archimedes' method was used to determine the density (ρ) and, as a result, the molar volume (Vm) of the samples. The ρ of the glasses increased from 2.917 to 5.003 (g/cm3), and the Vm increased from 24.155 to 27.074 (cm3/mol). The optical band gap of the samples was determined based on their UV–visible spectra. The structural study of the present glasses has been carried out by XRD patterns and FTIR spectra analysis. Numerous theoretical methods were used to calculate some parameters such as ionic radius, optical basicity, non-linear refractive index, and oxide ion polarizability. The mass attenuation coefficient MAC was obtained experimentally as well as theoretically by the Phy-X/PSD software programs and the obtained results were in very good agreement. The half-value layer HVL, mean free path (MFP), effective atomic number (Zeff), atomic cross-sections and electron cross-sections were evaluated for all the present glass samples. In addition, exposure build-up factor and energy exposure build-up factor were estimated for each glass up to penetration depths of 40 MFP. Moreover, the effective neutron removal cross-section (ƩR) was also calculated. The shielding properties of the prepared glass samples were compared with different concrete shielding materials, and commercial glasses, therefore, the prepared glasses outperformed all the aforementioned materials in terms of gamma ray shielding ability. [ABSTRACT FROM AUTHOR]

Glass samples were synthesized according to 10Li2O + 20CuO + xBi2O3 + (70 − x)B2O3, where x = 0, 10, 20, 30, 40 mol% by the melt-quenching method. The ability of the prepared glass to protect against gamma rays and neutrons was examined experimentally and theoretically. The mass attenuation coefficient (MAC) was calculated experimentally at energies of 0.662, 1.173, and 1.333 MeV using 137Cs and 60Co sources. The obtained results were compared with the theoretical ones using a Phy-x/PSD software program version 0.1.0.0. It was found that the experimental and theoretical results are very agreed upon. Moreover, other nuclear radiation shielding parameters were evaluated. The results showed that the addition of bismuth oxide leads to an improvement in the ability of the composite glass to attenuate gamma rays by increasing the values of MAC and Zeff, while it led to a decrease in the HVL and MFP, as well as the EBF and EABF. The results also showed that the addition of copper oxide led to an improvement in the ability of the present glass to slow down fast neutrons. Sample BiS40 showed the best result for gamma ray attenuation and sample BiS10 gave the best result for fast neutron removal cross section. The results were compared with some materials used for gamma ray shielding and fast neutron removal cross section, and it was concluded that samples Bi40 and BiS10 outperformed all commercial materials. [ABSTRACT FROM AUTHOR]

Nuclear radiation shielding parameters for glass samples composed of 20 mol.% Li2O-40 mol.% ZnO-40 mol.% P2O5: x wt.% Yb2O3 (x = 0, 0.2, 0.4, 0.6, 0.8, 1, 2) were evaluated. The samples were synthesized using the melt-quenching technique. The prepared samples were encoded Yb0.0, Yb0.2, Yb0.4, Yb0.6, Yb0.8, Yb1 and Yb2 according to the Yb2O3 content. X-ray diffraction (XRD) reveals that all the prepared samples were amorphous. The gamma ray shielding parameters such as mass attenuation coefficient (MAC), linear attenuation coefficient (LAC), half value layer (HVL) and mean free path (MFP) were obtained using Phy-X/PSD and XCOM software programs. The atomic cross section (ACS), electronic cross section (ECS), effective atomic number (Zeff), and electron density (Neff) were evaluated, as well as exposure buildup factor (EBF) and energy absorption buildup factor (EABF). The MAC values were found to be 26.304–31.872 cm2/g for Yb0.0–Yb2, respectively. The HVL and MFP values were found to be (0.008–0.007 cm) and (0.012–0.010 cm) for Yb0.0–Yb2, respectively. The ACS and ECS values were found to be (9.912 × 10−21 cm2/g) up to 13.06 × 10−21 cm2/g) and (3.990 × 10−23 up to 4.900 × 10−23 cm2/g) for Yb0.0–Yb2, respectively. The Zeff and Neff values were found to be (24.83–26.64) and (6.59 × 1023 up to 6.50 × 1023 electrons/g) for Yb0.0–Yb2, respectively. The results showed that the addition of Yb2O3 improves gamma-ray shielding properties of the glass. On the other hand, adding Yb2O3 to the prepared glass leads to a decrease in the removal cross section for fast neutrons (ƩR) from 0.103 to 0.096 cm for Yb0.0–Yb2, respectively. The gamma-ray shielding parameters for the present samples were compared with commercial concrete and glass used as gamma ray shields. [ABSTRACT FROM AUTHOR]

The aim of this paper is to the synthesis of ZnO– Bi 2 O 3 nanocomposites and characterization their optical, structure, and radiation shielding properties. The microwave –assisted hydrothermal method was adopted for the synthesis of ZnO– Bi 2 O 3 nanocomposites coded as 100Z, 25B075Z, and 50B-50Z. The FTIR and UV spectra of the samples were analysed to obtain their optical and chemical structure features. Also, the gamma-ray photon shielding parameters of the nanocomposites were evaluated using the EPICS2017 data library and by Geant4 Monte Carlo simulations for photon energies 1 keV–10 MeV. The FTIR spectrum analysis confirms the chemical bond structure of the samples. On the other hand, the optical bandgap of the nanocomposites decreased from 3.3 to 2.95 eV as the Bi 2 O 3 nanoparticles increased in the samples. Obtained values of the mass attenuation coefficients of the samples increased in the order of 100Z, 25B075Z, and 50B-50Z. Value of the effective atomic number varies from 13.91 to 29.55, 20.30–55.97, and 26.70–68.97 for 100Z, 25B-75Z, and 50B-50Z correspondingly. The 100Z, 25B075Z, and 50B-50Z nanocomposites were found to have comparable photon shielding ability with respect to high density common commercial glass shields. The present nanomaterials could be adopted as additives to enhance photon shielding competence of existing composite materials. [ABSTRACT FROM AUTHOR]

This research article aims to study the effect of CdO addition on the radiation shielding characteristics of boro-tellurite glasses in the composition of 50B 2 O 3 - (50-x) TeO2- xCdO, where x = 0, 10, 20, 30, 40 and 50 mol%. These glasses were exposed to gamma radiation and the transmitted gamma photons were evaluated for energies varying from 15 keV to 15 MeV using Geant4 simulation toolkit. The number of transmitted photons was then used to characterize the gamma shielding for the studied glasses in terms of linear/mass attenuation coefficients, MFP, Z eff , and HVL. The simulation outcomes were theoretically confirmed by using Phy-X software. The beta (electron) shielding characterization of the involved glasses was also investigated by determining the projectile range and stopping power using ESTAR software. Additionally, the fast neutron shielding characterization of the glasses was achieved by evaluating removal cross-section (Σ R). The results reveal that the CdO has a small influence on the shielding performance of the boro-tellurite glasses against gamma, beta, and neutron radiations. The shielding performance of the boro-tellurite glasses was compared with that of common shielding materials in terms of MFP. It can be concluded that the boro-tellurite glasses regardless of the concentration of CdO content have promising shielding performance to be used for radiation applications. [ABSTRACT FROM AUTHOR]

The gamma-ray and fast/thermal neutron shielding properties of bismo-borate glasses modified with Nd 2 O 3 in the form B 2 O 3 –Bi 2 O 3 –SrO-Nd 2 O 3 (BBSN0.0-BBSN5.7) were investigated. The newly developed Phy-X/PSD software and Geant4 simulation code were performed to achieve this goal by evaluating several parameters such as MAC, gamma photons dose rate, FNRCS, and scattering/absorption lengths and cross sections for thermal neutrons. At low photon energy; 0.015 MeV, MAC values varied from 76.72, 76.57, 76.43, 76.29, 76.10, and 75.93 cm2 g−1 for BBSN0.0, BBSN1.0, BBSN2.0, BBSN3.0, BBSN4.3, and BBSN5.7, respectively. The HVL followed reversible trend as follows; BBSN0.0 > BBSN1.0 > BBSN2.0 > BBSN3.0 > BBSN4.3 > BBSN5.7. The highest values for Z eff were found at low energy photon range (0.015 MeV) with the values of 76.71, 76.35, 76.00, 75.65, 75.21, and 74.75, while the lowest values were found at 1.5 MeV; 21.32, 21.42, 21.52, 21.61, 21.73, and 21.87 for BBSN0.0 – BBSN5.7, respectively. The gamma dose rate has a dramatic decrease with increasing the glass thickness from 1 mm to 5 mm. Furthermore, glasses with the highest concentration of Nd 2 O 3 show the best thermal/fast neutron shielding capability among the investigated glasses. One can conclude that BBSN5.7 glass owns the best shielding capacity among all BBSN glasses due to the highest LAC values comparing to other selected ones. [ABSTRACT FROM AUTHOR]