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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 this paper, five transparent and non-toxic glasses with the chemical identity : 75TeO 10MoO 3 10BaO (5- x)Sm 2 O 3 x Bi 2 O 3 with x = 0 (TMBS-0Bi), 2 (TMBS-2Bi), 4 (TMBS-4Bi), 4.5 (TMBS-4.5Bi), and 5 (TMBS-5Bi) were synthesized using analytic grade chemicals following the melt and quench process. The glasses were characterized for their physical, optical, structural and gamma radiation attenuation attributes. The glasses appear transparent with colour gradient dictated by chemical content. XRD data and analysis confirm the glassy nature of the prepared glasses. As the Bi 2 O 3 content increased, the glass density increased from 5.46 to 5.64 g/cm3. The direct optical bandgap also showed variations with TMBS-5Bi having the highest value of 2.56 eV. The mass attenuation coefficient (µ / ρ) of the glasses was determined through FLUKA simulation and direct XCOM calculations. Results showed great agreement between µ / ρ obtained from both methods. The analysis of photon response parameters of the glasses indicated energy and chemical content variations for photon energies 15–15000 KeV. Generally, parameters relating to gamma ray absorption show improvement as Bi 2 O 3 was enhanced in the glasses. therefore, TMBS-5Bi and TMBS-0Bi is the best and weakest photon absorber among the prepared glasses. The TMBS-5Bi offer good alternative as a transparent and environmentally friendly glass for radiation control applications. The TMBS-XBi glasses are attractive optical materials on one hand, they are also considered candidates in radiation protection functions. [ABSTRACT FROM AUTHOR]

The variation in dosimetric parameters such as mass attenuation coefficient, half value layer factor, exposure buildup factor, and the photon mean free path for different oxide glasses for the incident gamma energy range 0.015–15 MeV has been studied using MicroShield code. It has been inferred that the addition of PbO and Bi 2 O 3 improves the gamma ray shielding properties. Thus, the effect of chemical composition on these parameters is investigated in the form of six different glass compositions, which are compared with specialty concrete for nuclear radiation shielding. The composition termed ‘Glass 6’ in this paper has the highest mass attenuation and the smallest half value layer and may have potential applications in radiation shielding. An example dry storage cask utilizing an additional layer of Glass 6 as an intermediate shielding layer, simulated in MicroShield, is capable of reducing the exposure rate at the cask surface by over 20 orders of magnitude compared to the case without a glass layer. Based on this study, Glass 6 shows promise as a gamma-ray shielding material, particularly for dry cask storage. [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]

This paper presents the results of a study of the properties of a series of 0.5Bi 2 O 3 -(0.5-x)WO 3 -xPbO glasses obtained by sintering. Using the X-ray diffraction method, an amorphous glass structure is installed. Analysis of structural and optical characteristics showed that an increase in PbO concentration leads to an increase in density, as well as a decrease in the metallization criterion. It was found that an increase in PbO leads to a decrease in the band gap and an increase in the linear refractive index, a change in which indicates a change in the degree of structural disorder caused by impurities or electron traps. During experiments to determine the gamma-ray shielding efficiency, it was found that the best shielding efficiency is possessed by 0.5Bi 2 O 3 -0.125WO 3 -0.375PbO glasses, for which the mass attenuation coefficient is 3.6 times higher than that for 0.5Bi 2 O 3 -0.5WO 3 glasses. The results obtained are in good agreement with the literature data for similar structures, and the proposed method of obtaining can be used in the future for the technological process of industrial production of radiation-protective materials. • The results of a study of the properties of a series of 0.5Bi 2 O 3 -(0.5-x)WO 3 -xPbO glasses. • The change in the value of the band gap and linear refractive index. • The radiation protection efficiency versus PbO concentration. • The dependence of changes in linear and mass attenuation coefficient of gamma radiation. [ABSTRACT FROM AUTHOR]