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This paper aims to study gamma and beta attenuation characteristics of newly developed 60Se- 20Ge (20 – x)-Sb-xAg (where x varies from 0 to 20 mol% with step of 5) Chalcogenide glasses. Geant4 toolkit was utilized mainly to explore gamma-ray attenuation properties by determining linear attenuation coefficient (μ) for the chosen samples. The obtained results were compared with the theoretical approach applying via XCOM program. Then, we utilized the μ values to compute effective atomic number (Z eff) and half value layer (HVL). For the sample coded as SGSA1, the μ values are 0.191 and 0.180 cm−1 between 3 and 4 MeV, while they are 0.175 and 0.197 cm−1 between 6 and 15 MeV respectively. The HVL varied between 0.001492 and 0.001317 cm at 0.015 MeV and 0.021955–0.021439 cm at 0.05 MeV. ESTAR program was employed to investigate beta attenuation properties by estimation CSDA range and TSP factors of the incident electron. It was noted that there is a significant influence of silver on the radiation shielding characteristics of the tested materials. Moreover, we compared the studied glasses with commercial glasses and traditional concrete in term of MFP. The results showed the possibility of use the studied materials for the radiation shielding applications. [ABSTRACT FROM AUTHOR]

This paper focuses on the effect of Bi 2 O 3 content (up to 80 mol%) on mechanical features and radiation shielding characteristics of boro-tellurite glasses within TeO 2 –B 2 O 3 –Bi 2 O 3 system. The basic mechanical parameters such as oxygen molar volume, packing density, hardness, and elastic moduli were studied based on Makishima–Mackenzie's theory. The shielding studies of the TeO 2 –B 2 O 3 –Bi 2 O 3 glasses included gamma, electron and neutron radiations. The newly developed Phy-X/PSD program and Geant4 simulation were used to calculate the shielding parameters such as mass attenuation coefficient (μ/ρ), tenth value layer (TVL), mean free path (MFP), stopping power (ψ e)), removal cross section (RCS), CSDA range, effective atomic number (Z eff), and half value layer (HVL). The concentration of Bi 2 O 3 content had a significant effect on the gamma shielding competence of the investigated glasses. Form the results of gamma shielding studies, the highest μ/ρ (99.845 cm2/g) occurred at 0.015 MeV for TBB80 and the lowest μ/ρ (0.039 m2/g) occurred at 4 MeV for TBB40. The maximum values of Z eff for gamma interaction occurred at 0.02 MeV and they were 77.26, 78.81, 79.94, 80.80, and 81.48 for TBB40, TBB50, TBB50, TBB60, TBB70, and TBB80, respectively. The gamma shielding features of the investigated glasses were compared with those of various ordinary concretes, and Pb-free, Pb-based, and commercial glasses. The Bi 2 O 3 content had also a considerable influence on the electron shielding competence of the tested glasses. The maximum values of Z eff for electron interaction occurred at 14 MeV and they were 44.58, 47.72, 50.41, 52.75, and 53.73 for TBB40, TBB50, TBB50, TBB60, TBB70, and TBB80, respectively. The results revealed that the bismuth boro-tellurite glasses could be useful for the shielding against gamma, electron, and neutron radiations, wherein the Bi 2 O 3 content can be balanced according to the type and energy of radiation. [ABSTRACT FROM AUTHOR]

In this paper, the role of TeO 2 in radiation attenuating characteristics of xTeO 2 -10CaF 2 -(60–0.6x) B 2 O 3 -(30–0.4x) CaO glass system with x = 20, 25, 30, 35 and 40 wt% was investigated. The gamma radiation studies were carried out by utilizing Geant4 simulations and the newly developed Phy-X/PSD program. The gamma-shielding characteristics of the present glass samples were examined in terms of mass attenuation coefficient (μ/ρ), and some other related factors such as the effective atomic number (Z eff), and mean free path (MFP). The electron radiation-shielding characteristics were tested by determining the stopping power (ψ e) and CSDA range for each glass specimen. The neutron radiation-shielding characteristics were explored by evaluating the removal cross section (RCS) for the tested glasses. Moreover, the G-P method was employed to investigate the exposure buildup factor (EBF) for photon energies up to 15 MeV. The results showed that the TeO 2 content had a significant influence on the shielding ability of the investigated glasses against gamma and neutron radiations. In contrast, the TeO 2 content had an insignificant influence on the electron radiation-shielding capacity of the glasses involved. Additionally, the nuclear-shielding properties of the studied samples were compared with those of standard nuclear radiation shields. It can be concluded that the present calcium boro-tellurite glasses have a promising future to be used as a shielding material against gamma, electron and neutron radiation, wherein the TeO 2 concentration can be balanced according to the desired application. [ABSTRACT FROM AUTHOR]

In this paper we discussed the optical and radiation shielding properties are strongly dependent on the physical parameter viz; (i) interionic interaction parameter, A(n 0) , (ii) coordination number, CN, (iii) single bond strength (B M-O) and (i v) optical basicity, Λ(n 0) of glasses (95-x) TeO 2 – 5Ta 2 O 5 -xBi 2 O 3) where x = 5, 10, 15, and 20 in mol %. Furthermore, the various optical parameters viz ; linear refractive index, optical absorption coefficient, optical energy gap, Urbach energy, density, oxygen molar volume, nonlinear refractive index, molar refraction, oxygen packing density, reflection loss, molar electronic polarizability of fabricated glasses were estimated. The shielding parameters viz; mass attenuation coefficient, linear attenuation coefficient, half value layer, mean free path, tenth value layer, effective electron number, effective atomic number, atomic and electronic cross sections have been calculated of fabricated glass against a wide range of ionizing energy ranging from 0.015 to 15 MeV. Results showed that increasing the concentration of Bi 2 O 5 from 5 to 20% led to an increase in the linear attenuation coefficient (LAC). Compared with commercially available standards and reported some tellurite glasses to contain Bi 2 O 3 in the literature, the investigated material showed superior performance at energies ranging between 800 keV and 10 MeV. Radiation protection efficiency (PRE) of 70TeO 2 –5Ta 2 O 5 –20Bi 2 O 3 glass varied from 99.9 to 83.9% at low energy from 15 to 200 KeV. Therefore, this glass has a high density, refractive index, and a superior capability of radiation shielding materials at low energy. • Increasing Bi 2 O 3 into the glass structure enhances optical and radiation protection efficiency (PRE%) characteristics. • The TTB1 glass has the lowest value of E o p t = 2.71 eV and TTB4 has the lowest value of Δ E = 0.41 eV. • The prepared glass system can be used for radiation shielding in medical applications at low energy from 15 to 200 keV. • The RPE% of the fabricated glasses decreased from 100 to 72.75% with the photon energy increased from 15 to 200 keV. [ABSTRACT FROM AUTHOR]

This paper evaluates the γ-radiation shielding traits of some new types of borate glasses of composition (70–x)B 2 O 3 –10Bi 2 O 3 –10BaO–10CdO–xPbO (where 0 ≤ x ≤ 20 mol%) prepared using melt quenching method. As-quenched samples were characterized to determine the effects of various PbO contents on their γ-radiation shielding properties. XRD patterns of the samples verified their amorphous nature. The Phy-X and XCOM was used to compute the mass attenuation coefficients of the glasses and then compared with the experimental data. The γ-radiation shielding performance of the proposed glasses were evaluated in terms of diverse attenuation parameters like mean free path, half and tenth value layer, atomic cross-section, electronic cross-section, effective atomic number and effective electron density. The γ-radiation shielding performance of the glasses were significantly improved with the increase of PbO contents. This new borate glass system is established to be advantageous for the radiation shielding applications. • The borate glass samples with different PbO content were prepared by the standard melt-quenching method. • The μ/ρ values of the glasses were increased with the increase of the PbO content. • The relatively higher Zeff at lower energies due to the dominance of PE effect. • Promising HVT and TVL achieved with the new prepared glasses. • The proposed glass improves the efficiency of IR shielding material. [ABSTRACT FROM AUTHOR]

In the present paper, glass sample with the chemical composition xNb 2 O 5 +0.20Bi 2 O 3 +0.20CdO+0.10ZnO+ (0.50-x)B 2 O 3 (where x = 0.05, 0.10, 0.15, 0.20, 0.25 mol fraction) were prepared by melt quenching-annealing technique. The density, molar volume, oxygen molar volume (OMV) of the glass samples are found to increase increases from 5.35 to 5.65 gcm−3, 32.69–37.32 cm3/mole, 14.323–14336 cm3/mole, respectively, with the increase in molar concentration of Niobium pentoxide. The value of Poisson's ratio shows a very small variation in the range of 0.240–0.247 for the present glass matrix, however these results confirms that the prepared glass samples have high cross link density. The linear attenuation coefficients were measured experimentally by employing narrow beam transmission geometry (total scatter acceptance angle = 2.22°) with NaI(Tl) spectroscopy in the gamma photon energy range of 59.54–1332 keV. These values of linear attenuation coefficient were then further used to calculate other attenuation parameters namely Half Value Layer (HVL), Radiation Protection Efficiency (RPE), Mass Attenuation Coefficient (MAC), effective atomic number (Z eff), electron density (N e) and Buildup Factor (BF). Measured values of attenuation parameters have also been compared the values obtained theoretically using online software Phy-X/PSD and Py-MLBUF as well as with values obtained through FLUKA (Monte-Carlo) simulations code. Excellent agreements have been observed between experimental, theoretical and simulation results for the prepared glass samples. In addition to this, fast neutron removal cross sections (∑ R cm−1) were calculated for the glass matrix under investigations. On the basis of the obtained results, it has been reported that the prepared glass samples possess superior shielding efficiency against gamma rays and fast neutrons as compared to conventional shielding materials. • Niobium–Bismuth–Cadmium–Zinc-Borate glass samples were prepared by Melt quenching-annealing technique. • Narrow beam transmission geometry has been used to measure the attenuation coefficients. • Phy-X/PSD, Py-MLBUF and FLUKA code has been used to calculate the theoretical values of attenuation parameters. • Physical and structural properties of the prepared glass samples were also calculated. • Radiation shielding effectiveness has been compared with standard shielding materials in terms of HVL values. [ABSTRACT FROM AUTHOR]

The current paper addresses the influence of Rb 2 O in the lithium-borotellurite (LBT) glass system for the first time. For this, the glass system (25-x)Li 2 O–15B 2 O 3 –60TeO 2 -xRb 2 O was designed where x: 0, 5, 10, 15, 20, and 25 mol %. An extensive investigation was carried out to understand the alterations in physical, optical, thermal, and mechanical properties with the use of theoretical calculations. The user-friendly Phy-X/PSD software was employed to demonstrate the nuclear radiation protection properties. From physical property calculations, the addition of Rb 2 O from 0 to 25 mol% increased average molecular weight (AMW) from 113.68 to 152.94 g mol−1 and glass density (ρ glass) from 4.2743 to 4.7710 g cm−3. Likewise, molar volume (V m), oxygen molar volume (V O), oxygen packing density (OPD), and number of bonds per unit volume (n b) were considerably changed by the increasing Rb 2 O concentration. According to the optical calculations, the refractive index (n) increased from 2.3348 to 2.6104, while the dielectric constant (ε) increased from 5.45 to 6.81. Moreover, the metallization criterion (M) showed a decreasing trend, and implied increasing insulation with the increase in Rb 2 O in the glass system. For thermal property estimations, viscosity versus temperature profiles clearly indicated that all R-series have the ability to form glass, but decreasing the Li 2 O caused an increment in glass melting temperature. The mechanical moduli determinations via the Mackenzi-Makishima model demonstrated that Young's (E), bulk (B), shear (S), and longitudinal (L) moduli were gradually decreased by introducing Rb 2 O into the glass network. From the perspective of radiation shielding calculations, the essential parameter, linear attenuation coefficient (LAC), effectively improved by increasing the doping rate of Rb 2 O. Based upon the LAC values, the other critical parameters such as mean free path (MFP), half-value layer (HVL), and effective atomic number (Z eff) were successfully evaluated. Additionally, build-up factors such as exposure (EBF) and energy absorption (EABF) were assessed with the implementation of G-P progression. They showed that sample-R25 ensured better gamma-ray shielding properties compared to the other samples. Lastly, fast neutron removal cross-section (FNRCS) determinations displayed decreasing behaviour with the increasing Rb 2 O content, which is not convenient for effective neutron shielding abilities. All in all, the Rb 2 O-reinforced borotellurite glass can serve as an alternative radiation shielding material. • The first Rb 2 O-added Li 2 O–B 2 O 3 –TeO 2 glass was evaluated. • The ρ glass increased from 4.2743 to 4.7710 g cm−3 for R0 to R25 series, respectively. • The highest LAC values for the sample-R25 were clearly reported in all photon energies. • The lowest HVL is achievable for R25 as 1.84 cm at 0.662 MeV. • EBF and EABF indicated that sample-R25 ensured better gamma-rays shielding properties. [ABSTRACT FROM AUTHOR]

• Newly developed Zinc-Tellurite glasses have been fabricated. • Nuclear shielding characterization of fabricated glasses was studied. • The experimental results then compared with simulated MCNPX and theoretical WinXCOM data. • ZTT3 glass sample with highest Ta 2 O 5 contribution has excellent nuclear radiation shielding ability. In this paper, the nuclear shielding properties of newly fabricated Zinc-Tellurite glasses doped with Ta 2 O 5 with a composition (25ZnO.75TeO 2) 100-x. (Ta 2 O 5) x (x=0, 1, 2, 3 mol%) were studied. Ta 2 O 5 doped Zinc-Tellurite glasses prepared by the traditional melt quenching method. The mass attenuation coefficients were achieved for prepared glasses at 0.081-0.383 MeV photon energies employing experimental transmission measurements, which were performed with 3 Ci Ba-133 point source and Ultra Ge detector. The experimental results were compared with simulated MCNPX and theoretical WinXCOM data. Moreover, another important nuclear shielding parameters such as mass attenuation coefficient, half value layer, effective atomic number, effective electron density, equivalent atomic numbers, alpha and proton projected ranges, mass stopping power in the protection of gamma, neutron, alpha and proton radiation were calculated. In addition, buildup factors of investigated glasses were determined by using the G-P fitting method. Moreover, effective removal cross section Σ R and transition factors were determined. According to the results, the addition of Ta 2 O 5 to the glass samples has a positive effect on the performance of nuclear shielding effects of the glass samples. It can be concluded that ZTT3 glass sample with the highest Ta 2 O 5 contribution has excellent nuclear radiation shielding ability among the other fabricated glass samples. [ABSTRACT FROM AUTHOR]

• Five samples of vanadyl boro-phosphate glasses V 2 O 5 -P 2 O 5 -B 2 O 3 have been synthesized. • Density, XRD, and UV–vis measurements have been performed. • The (E Gap) and n were evaluated by Tauc's, ASF, and DASF methods. • The (μ/ρ) has been computed using WinXCOM program. • Depending on the (μ/ρ), (HVL), (MFP), (Z eff) have been evaluated. In this paper, novel vanadyl boro-phosphate glasses with the chemical formula (100 − x)(0.5V 2 O 5 -0.5P 2 O 5)-xB 2 O 3 (x = 0, 2, 4, 6, 8 mol%) have been synthesized using melt-quenching method. The amorphous state of the glasses was checked through XRD measurements. UV–vis spectra were recorded in the range of 200–1100 nm wavelength. The optical energy band gaps via Tauc's model, absorbance spectrum fitting (ASF), and the first derivation of the absorption spectrum fitting (DASF) methods have been calculated for all glasses. Urbach's energy and refractive index of the prepared glasses also calculated. Gamma-photons shielding capability of the proposed glasses have been evaluated in terms of mass attenuation coefficient (μ/ρ) which calculated using WinXCOM software. Based the (μ/ρ), half value layer (HVL), mean free path (MFP), and effective atomic number (Z eff) were calculated. The results show that energy gaps for all glasses were close together, but the index of refraction was high around 4. Results of HVL, MFP, and Z eff confirmed that VPB0 glass sample (free with boron) has good attenuation capability compared to other VPB (with boron additions) glasses. Moreover, gamma-ray protection ability of the current glasses was compared with that of some commercial glasses. It can be concluded that the prepared glass samples could be useful to design or develop novel shields for radiation protection applications. [ABSTRACT FROM AUTHOR]

This paper examines the nuclear shielding characteristics for two different lead-zinc-tellurite glass systems with the composition of TeO 2 –Bi 2 O 3 – ZnO–PbO and TeO 2 –Na 2 O – ZnO–PbO coded as series A and series B, respectively. Nuclear shielding features of these glasses have been tested in terms of mass attenuation coefficient (μ/ρ), half value layer (HVL), removal cross section (∑ R), exposure buildup factor (EBF), effective atomic number (Z eff), and mean free path (MFP). The μ/ρ values of these systems were generated by Geant4 Monte Carlo simulations over an extended energy range of 0.015–15 MeV. The generated data of μ/ρ were confirmed by XCOM calculations. The results show that the nuclear shielding ability of the lead-zinc-tellurite system increases as Bi 2 O 3 content increases in the glasses of series A and as PbO content increases in the glasses of series B. Moreover, the nuclear shielding ability of the current glass systems have been compared with those of some conventional shielding materials and commercial glasses. It can be concluded that the present lead-zinc-tellurite glass systems could be useful to serve as novel shields for nuclear protection applications. • Lead-zinc-tellurite glasses are reported for nuclear shielding application. • Geant4, XCOM, and G-P methods are used for computational work. • Influence of Bi2O3/PbO on the shielding properties is discussed in details. • TBZP10 glass was found as promising alternative for the conventional shields. [ABSTRACT FROM AUTHOR]