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Bismuth-boro-tellurite glasses reinforced with TiO2 with the chemical formula (58−X)B2O3 + 19.5TeO2 + 0.5Nd2O3 + 12Bi2O3 + 10Li2O + XTiO2 (where X = 0 mol.% for the sample labeled NdTi0 to X = 10 mol.% for the sample labeled NdTi10, in steps of 2.5 mol.%) were investigated. Samples were prepared using the conventional melting and quenching technique. The impact of TiO2 on the structural, optical, and physical characteristics and γ-ray protection competence of the NdTiX samples was investigated. The amorphous state of NdTiX samples was confirmed via x-ray diffraction (XRD) measurements. The density (Ds) increased from 3.52 g/cm3 to 3.90 g/cm3. The molar volume (Vm) declined from 37.49 cm3/mol to 34.15 cm3/mol. The ultraviolet (UV) absorbance spectra confirmed that ten essential peaks reflected the electronic transitions from the ground state (4I9/2) of Nd3+ to higher states. The indirect optical energy gap (Eg) decreased from 3.59 eV for the NdTi0 sample to 3.18 eV for the NdTi10 sample. Urbach energy (EU) values declined from 0.47 eV to 0.23 eV. The refractive index (n) increased from 2.25 to 2.35. Molar refractivity (Rm), reflection loss (RL), and molar polarizability (αm) were enhanced as TiO2 content increased in the glass networks. The mass absorption coefficient (MAC) followed the order (NdTi0)MAC < (NdTi02.5)MAC < (NdTi05)MAC < (NdTi07.5)MAC < (NdTi010)MAC. The half-value layer (HVL) followed the order (NdTi0)HVL > (NdTi02.5)HVL > (NdTi05)HVL > (NdTi07.5)HVL > (NdTi010)HVL. The Zeff values followed the same order as the MAC, while the mean free path (MFP) followed the same order as the HVL. The obtained results showed that NdTiX samples can be used in optical and γ-ray shielding applications [ABSTRACT FROM AUTHOR]

Influence of Gd2O3 on the structure, physical, neutrons and gamma-photon protection features of newly prepared (50-x)B2O3 + 25Bi2O3 + 25Na2O + xGd2O3 glasses with different Gd2O3 concentrations was investigated. Glasses have been prepared via solid-state conventional method and encoded as Gd0, Gd1, Gd2, Gd3, and Gd4, respectively, according to xGd2O3 values. X-ray diffraction measurements proved that all Gd-glasses were in an amorphous nature. The density of the samples was increased from 5.1021 to 6.3210 g.cm−3. The mass attenuation coefficient (MAC) values were simulated via MCNPX in photon energy range of 15 keV–15 MeV and verified via XCOM program. The MACs were ranged from 28.69 to 32.52 cm2.g−1, while linear attenuation coefficient values were found to be ranged from 142 to 201 cm−1 for Gd0 and Gd4, respectively. The Gd4 glass has the lowest half value layer (HVL, highest radiation shielding capacity) among all the prepared Gd-glasses, several concretes, and conventional glasses. The atomic cross section (ACS) and electronic cross section (ECS) values were enhanced with the increment of Gd ratio in the sample compositions, and the measures of ACS were much greater than the ECS values. The effective atomic number (Zeff) values were ranged from 62.7 to 63.4 for Gd0 to Gd4, respectively. The effective conductivity (Ceff) is directly proportional to the density and effective electron density of the glass samples. By utilizing the Phy-X/PSD program, the maximum values of exposure buildup factor were slowly decreased with the addition of Gd2O3 contents and decreased from 55.8 to 55.3, while the highest energy absorption buildup factor increases slowly from 70.5 to 71.1 for glasses Gd0 and Gd4, respectively. The lowest values of fast neutron removal cross section (∑R, cm−1) were obtained for glasses Gd0 (∑R = 0.179 cm−1), while the highest value was obtained for glasses Gd4 (∑R = 0.179 cm−1). [ABSTRACT FROM AUTHOR]

Mechanical, gamma-ray buildup factors, and neutron-sensing properties of cupric alumino lithium borate glasses of the form xCuO–(20−x)Li2O–60B2O3–20Al2O3: x = 0.0, 0.2, 0.4, 0.8, 1.2, 1.6, 2.0, and 2.4 mol% have been examined. The bond compression values of Young's (EB–C) elastic modulus were enhanced from 94.739 to 98.959 GPa, from 36.267 to 37.909 GPa for shear (SB–C), and from 129.739 to 135.081 GPa for longitudinal (LB–C). Poisson's ratio (σB–C) for BLiAlCu glasses was decreased from 0.3061 to 0.3051. Makishima–Mackenzie elastic moduli showed that the replacement of CuO by Li2O leads to a slight increase of values of (EM–M) from 54.269 to 55.321 GPa, (KM–M) from 31.931 to 33.448 GPa, and (SM–M) from 22.301 to 22.592 (GPa). Poisson's ratio (σM–M) for glasses was increased from 0.216 to 0.224. The position of the EABUF and EBUF peaks vary with depth and chemical composition of the glasses; however, all the peaks appear within 0.08 and 0.15 MeV and shifting to higher energy as depth increases. Comparing the BUFs for the different glasses, it is apparent that BUFs decreases with increase in Cu content of the glass system at low energies. Hence, (BUFs)BLiAlCu0.0 > (BUFs)BLiAlCu0.4 > (BUFs)BLiAlCu0.8 > (BUFs)BLiAlCu1.2 > (BUFs)BLiAlCu1.6 > (BUFs)BLiAlCu2.0 > (BUFs)BLiAlCu2.4 at 0.015. The increase of CuO content of the glasses leads to improve in the fast neutron removal capacity. [ABSTRACT FROM AUTHOR]

Photon and neutron shielding factors and elastic moduli of phosphate glass doped with Tm3+ ions (abbreviated as PPKANT glasses) have been analyzed. MCNP-5 simulation code, and Phy-X/PSD software have been utilized to estimate the gamma rays and neutron shielding capacity. Furthermore, Makishima and Mackenzie’s theory has been performed to calculate elastic moduli. Young’s modulus, bulk modulus, and shear modulus have been varied from 40.71 to 43.62 GPa, 28.01 to 30.65 GPa, and 16.18 to 17.27 GPa, respectively. Poisson’s ratio changed from 0.257 for PPKANT0.1 glass to 0.263 for PPKANT4 glass. At low gamma photon energy (0.015 meV), the LAC increased with the increase of Tm3+ content (LAC = 155.54 and 170.18 cm−1 for glass samples PPKANT0.1 and PPKANT4, respectively). At high energy (15 MeV), the LAC changed from 0.118 to 0.124 cm−1 for PPKANT0.1 to PPKANT4. The highest values of the HVL decreased from 5.734 to 5.570 cm. The trend of MFP was like the HVL trend. At 15 MeV, the values of the EBF and EABF were rapidly increased with the increase in the penetration depth (PD), especially for PD > 20 mfp. The lowest ∑R was achieved for glasses PPKANT4 with 4 mol % Tm2O3, where ∑R = 0.02561 cm2g−1. The investigated PPKANT glasses can be considered good neutron and photon shields compared to some traditional radiation shielding materials. [ABSTRACT FROM AUTHOR]

A study of photon attenuation and optical properties was performed for (20Bi2O3–60B2O3–(20-y)PbO–yTiO2), where y = 0.0, 1.0, 2.5, 5.0, 7.5, and 10.0 wt%) glassy system. UV–Vis absorption measurements for the glasses in the range of 90–1100 nm wavelengths have been recorded. Based on the absorption spectra, the band gap of optical energy for each glass sample has been evaluated using absorbance spectrum fitting ( E Optical ASF ) and derivative absorbance spectrum fitting ( E Optical DASF ) models and compared with those obtained by Tauc's method. E Optical ASF varies from 2.405 to 2.008 eV, while E Optical DASF takes values from 3.000 to 2.914 eV. Indeed, different optical parameters such as refractive index, molar polarizability, molar refractivity, metallization criterion, dielectric constants, optical transmission, reflection loss, band gap of optical energy-based metallization criterion, and refractive index-based metallization criterion have been evaluated. Moreover, several shielding parameters such as mass attenuation coefficients, linear attenuation coefficient, half-value layer, tenth-value layer, mean free path, effective atomic numbers, and effective electron densities have been evaluated using the WinXCOM program in the energy range 0.010–15 MeV for the prepared glass system. At 1 MeV photon energy, the half value layer for the investigated glasses takes values from 2.03 to 2.15 cm. The results showed that the studied glasses can be applied as candidate for radiation shielding materials according to their coefficients of mass attenuation and HVL values, especially the composition with the highest value of PbO (20 wt%), which introduced good nuclear radiation shielding. [ABSTRACT FROM AUTHOR]

New zinc lead borate glasses with (50B2O3–10ZnO–(40 − y) PbO)–yFe2O3: 0 ≤ y ≤ 10 wt%) composition were synthesized by the conventional melt-quench technique. The amorphous nature of the glasses was tested by using X-ray diffraction spectroscopy. FTIR spectra for the glasses were recorded in the range of 4000–400 cm−1. Physical properties of the proposed glasses were evaluated. The mass attenuation coefficients (μ/ρ) for the glasses were calculated by the Geant4 simulation toolkit code and XCOM software within the photon energy range 365–2510 keV. Different γ-ray shielding parameters such as half-value layer, tenth value layer, and transmission fraction for the proposed glasses were evaluated using the obtained values of the (μ/ρ). Results reveal that for 1 cm glass thickness, the (50B2O3–10ZnO–30PbO)–10Fe2O3 sample has the highest transmission, due to the lower amount of Pb, and thus poorer shielding capability among the other glass samples. In addition, the probabilities of γ-ray interaction with the studied glasses were investigated. [ABSTRACT FROM AUTHOR]