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This study presents the photon shielding factors, viz, the linear attenuation (LAC) and mass (MAC) attenuation coefficients, half-value layer (HVL), transmission factor TF, and effective atomic number Z eff of xCo2O3-(100 − x)[80 TeO2–19Li2O–1ZrO2] glass–ceramic system (for 0 ≤ x ≤ 20 mol%) synthesized by the melt-quench method. The parameters were estimated using FLUKA simulations and compared with WinXCOM calculations for low photon energies in the range 241–2510 keV. Generally, LAC values smoothly decline with photon energy with highest (lowest) value at minimum (maximum) energy. The corresponding highest (lowest) values of LAC was 0.961 (0.205), 0.955(0.206), 0.911 (0.205), and 0.853 (0.205) cm−1 for Co2O3 concentration of 0–20 mol%. The HVL values of CoTeLiZr1 and CoTeLiZr4 samples equaled 0.72 cm and 0.81 cm, correspondingly, at photon energy 284 keV and both increased to 3.38 cm at 2506 keV. At minimum (maximum) photon energy, Zeff value was obtained as 27.94 (19.27), 27.73 (19.16), 26.08 (18.35), and 24.06 (17.59) for CoTeLiZr1, CoTeLiZr2, CoTeLiZr3, and CoTeLiZr4, respectively. Analysis of all estimated parameters shows that the gamma photon shielding efficiency improves according to the trend CoTeLiZr1 > CoTeLiZr2 > CoTeLiZr3 > CoTeLiZr4. The partial replacement of TeO2 with CoO3 leads to the decline in the photon shielding efficacy and mass density of the glass–ceramics. The CoTeLiZr1–4 exhibit substantially enhanced shielding efficiency with respect to ordinary concrete, barite concrete, and RS-253-G18 commercial shield. The present materials thus have great potential as gamma photon absorbers in nuclear facilities where low energy photons are applied. [ABSTRACT FROM AUTHOR]

In the present work, we have studied the effect of Sb2O3 addition on gamma, neutron, and charged particles attenuation properties of tellurite glasses in the chemical structure of 84TeO2 + xSb2O3 + 1V2O5 + (15-x)Nb2O5, where x is between 0 and 15 mol% with step of 5. Monte Carlo simulations (by using FLUKA code) were employed to investigate the gamma attenuation parameters for photon energies of 0.6, 1.25, 1.5, 2, 3, 5, and 10 meV. For every photon energy, the results of FLUKA simulations were theoretically approved using the XCOM approach. The obtained results show that the Sb2O3 addition increased the mass attenuation coefficient (µ/ρ) ranges from 0.03318 to 0.08003, 0.03334–0.08021, 0.03349–0.08038, and 0.03363–0.08054 cm2 g−1 for TSVN1, TSVN2, TSVN3, and TSVN4, respectively. For the studied glasses, the maximum (minimum) effective atomic number (Zeff) was obtained at 10 meV (1.25 meV) with corresponding values of 28.85 (21.58), 29.80 (22.27), 30.77 (23.00), and 31.78 (23.77). The exposure rate (ER) follows the trend: (ER)TSVN4 > (ER)TSVN3 > (ER)TSVN2 > (ER)TSVN1. Different effects of Sb2O3 addition were observed on the shielding properties for the thermal and fast neutrons. Finally, the influences of Sb2O3 addition on the attenuation features of the studied glasses were discussed in detail for charged particles such as protons, alpha particles, and electrons. It is concluded that the investigated glass specimens can be utilized for various nuclear applications as non-toxic shields against the radiation of gamma, neutron, and charged particles. [ABSTRACT FROM AUTHOR]

This work focused on investigating the mechanical, optical features and gamma-ray shielding parameters of different five glasses coded as W1, W2, W3, W4, and W5 based on 0.8[xBaO (1-x)MgO]−0.2WO3−2TeO2:x = 0, 0.3, 0.5, 0.7, and 1 mol%. According to Makishima–Mackenzie's model, the total ionic packing density (Vt) and the total dissociation energy (Gt) for the investigated glasses were computed. Then, the main mechanical features (elastic moduli and Poisson's ratio) haven been calculated. The optical features such as optical electronegativity (χ*) and linear dielectric susceptibility (χ(1)) and other related parameters for the W1–W5 glasses were also computed. Utilizing the newly Phy-X/PSD program, mass attenuation coefficient (MAC) has been computed. Based on MAC values, linear attenuation coefficient (LAC), half value layer (HVL), mean free path (MFP), and effective atomic number (Zeff) as radiation shielding parameters were evaluated. Results revealed that the (Vt) increased from 0.39 to 0.49, while (Gt) decreased from 84.94 × 106 to 45.33 × 106 (KJ/m3) for W1 to W5 glasses. The elastic properties varied from 76.21 to 44.32 GPa for Young's modulus, from 29.25 to 18.23 GPa for shear modulus, from 32.29 to 26.00 GPa for bulk modulus, from 70.91 to 50.30 GPa for longitudinal modulus, and from 0.15 to 0.22 for Poisson's ratio. The value of χ* changed from 0.84 to 0.41, while χ(1) changed from 0.62 to 0.36. HVL and MFP values are in the ascending order of W1 > W2 > W3 > W4 > W5. Therefore, the W5 glass (contains the highest concentration of BaO) has the best radiation shielding efficiency among the other samples W1–W4. Correlations between shielding features (MAC and HVL) at different photon energy are estimated, where MAC and HVL have been improved by increasing the BaO in W1–W5 glasses. [ABSTRACT FROM AUTHOR]

Electronic polarizability, dielectric constants, and the capability of using (24-x)PbO–47P2O5–23Na2O–6Al2O3: x = 0.0, 0.5, 1.0, and 3.0 mol% MoO3 as γ-rays shielding materials were investigated. The linear refractive index of glasses changed from 2.059 to 2.514. The molar polarizability was directly proportional to molar refraction. The mass attenuation coefficients varied between 0.1850- 0.0401 and 0.1762- 0.0399 cm2/g for Mo0.0 and Mo3.0 glasses between 0.284 and 2.506 MeV. The replacement of PbO by MoO3 is found to decrease the attenuation ability of the tested samples. The maximum linear attenuation values for all samples occur at 0.284 MeV and equal to 0.684, 0.661, 0.626, and 0.546 cm−1 for Mo0.0, Mo0.5, Mo1.0, and Mo3.0 glasses, respectively, which suggested that the tested Mo0.0–Mo3.0 samples have better attenuating behavior at lower energies. The effective atomic number decreases in the order Mo0.0, Mo0.5, Mo1.0, and Mo3.0. Mo0.0 glass showed the highest effective atomic number among the tested glasses, which revealed that Mo0.0 has better attenuation features among the investigated glasses. The minimum effective atomic number was found at 1.33 MeV and equal to 12.45, 12.42, 12.39, and 12.26 for the Mo0.0, Mo0.5, Mo1.0, and Mo3.0 samples. The Phys-X software was applied to determine the half value thickness for the investigated glasses between 0.284 and 2.506 MeV. The usage of different percentage of PbO and MoO3 in the chosen glasses had been found to notably affect the half value thickness of the glasses. The half value thickness values are small at low energy and then increase with increasing the energy of the photon and reach the maximum values at 2.506 MeV. At 2.506 MeV, the half value thickness varied between 4.678 and 5.601 cm. [ABSTRACT FROM AUTHOR]

In this study, the optical properties and gamma-ray competence of barium–lead borate glasses with chemical form BaO–B2O3–PbO have been investigated. The optical features such as optical energy gap (Eoptical), linear refractive index (n), molar refraction (Rmolar), molar polarizability (αmolar), metallization criterion (M), dielectric constants (static and optical), reflection loss (Rloss), optical transmission (Toptical) and others for the investigated glasses were calculated. Results show that Eoptical measures in (eV) and Eoptical values were changed from 3.18 to 2.53 eV, while n increases from 2.350 to 2.536. Phy-X/PSD software has been applied to report the radiation attenuation factors of the tested glasses. The results implied that all samples have the high attenuation ability at lower energies and the maximum µ/ρ is reported at 15 keV and lies within the range of 29.398 and 68.228 cm2/g. The minimum effective atomic number (Zeff) occurs at 1.5 MeV and equals to 10.90, 11.30, 12.41, 13.57, 16.79 and 20.55 for the tested glasses. At 0.2 MeV, the Zeff changes from 19.42 to 49.10 due to the increase of PbO from 0.5 to 30 wt%. The half value layer (HVL) results revealed that the current glasses have very low HVL values at the 15 keV (in the range of 0.00202 to 0.00671 cm). The HVL increases with the energy which indicates that the photon with high energy can penetrate the samples easily. The HVL results also showed that increasing the density of the samples leading to reduce the HVL and BBP30 has the thinner HVL, while BBP0.5 has the thicker HVL. [ABSTRACT FROM AUTHOR]