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Gd 2 O 3 is often used as an absorber in nuclear fuel shielding because of its excellent neutron absorption capacity. However, Gd element releases prompt gamma rays when absorbing neutrons, which threatens the safety of personnel and equipment. In this paper, a new absorber, Gd 2 O 3 @W core-shell powder, is proposed, which can simultaneously absorb thermal neutrons and prompt gamma rays. Firstly, MCNP5 software was used to explore the influence of tungsten layer thickness on γ-ray attenuation ratio, and the thickness of tungsten layer required to shield prompt γ-ray was obtained. Then, in order to explore an effective tungsten plating method, Gd 2 O 3 @W core-shell powders were prepared by three methods: powder coverage sintering, sol-gel method and immersion method. The Gd 2 O 3 @W core-shell powders prepared by the above three methods were observed and analyzed by SEM and EDS. The results show that the core-shell powder prepared by immersion method is more uniform and dense. Finally, the composition and shell thickness of the Gd 2 O 3 @W core-shell powder prepared by immersion method was further studied. The results show that the W layer thickness is about 200–600 nm, and there is a diffusion zone between the shell and the core, resulting in new phases Gd 2 W 2 O 9 and Gd 2 WO 6. The prepared Gd 2 O 3 @W core-shell powder in this paper.can be used as a co-absorber of neutron and gamma rays for shielding composites. [ABSTRACT FROM AUTHOR]

In this paper, a novel nuclear shielding material capable of shielding neutrons and gamma rays, WB-reinforced Al (WB/Al) composites, was prepared by spark plasma sintering (SPS) process. The microstructure of the composites was characterized, and the effects of WB content, heat treatment and matrix type on the properties of the composites were discussed. The results demonstrate that the WB particles are uniformly dispersed in the aluminum matrix and formed a good binding interface with the matrix. WAl 12 as an interfacial reaction product is identified, and segregation of Si and Mg elements at the reinforcement/matrix interface occurs. The mechanical properties of the WB/Al composites are sensitive to the WB content. The hardness, elastic modulus and bending strength of the composites increase monotonously as the WB volume fraction increasing, up to 234%, 107% and 91.6% higher respectively than those of the monolithic 6061Al. However, the tensile strength reaches a peak point when the volume fraction is 20%. The effects of T6 treatment and matrix type are not pronounced, especially for the composites with high WB content. The thermal neutron and gamma ray shielding properties of the composites both increase with the increase of material thickness and WB content. The WB/Al composites developed in this work show good application prospects in the field of nuclear radiation protection, due to their good mechanical properties and well neutron and gamma-ray shielding performance. [ABSTRACT FROM AUTHOR]

This paper includes a comprehensive analysis of the radiation shielding, optical properties, and structural makeup of polymer composites that contain Dy 2 O 3 additions. XRD-pattern investigates the effect of loading Dy 2 O 3 content on PS, with the average crystallite size of Dy 2 O 3 decreases from 39 nm to 30 nm as Dy 2 O 3 increases from 2.5 to 7.5 wt% in the PS matrix. The optical properties of the nanocomposites showed that with the increase in the Dy 2 O 3 content, the transmittance, as well as the direct and indirect band gap, decreased. The E g Indirect bandgap decreased from 3.1 to 2.75 eV with a Dy 2 O 3 increase from 0 to 7.5 wt%, while the E g direct Bandgap reduced from 4.6 to 4.35 eV. While the Urbach energy Eu and the refractive index increase, Eu rises from 0.48 to 0.60 e V, and n improves from 1.4 to 1.78 from 0 to 7.5 wt%. In order to conduct an accurate analysis of the gamma-ray attenuation capabilities of the selected new polymer composites, these composites were manufactured with varying proportions of the additive components. With the assistance of a Na(Tl) detector, experimental assessments were carried out on the gamma rays throughout a broad spectrum of photon energies, ranging from 81 keV up to 1416 keV. The sample encased in PS/Dy7.5 demonstrates excellent radiation attenuation, and it is important to note that this novel polymer shielding material does not include any hazardous components. • "Dy2O3 in PS enhances radiation shielding". • "Increased Dy2O3 reduces PS's transmittance". • "Dy2O3 addition lowers bandgap energy". • "Higher Dy2O3 increases refractive index". • "Dy2O3/PS composites ideal for radiation protection". [ABSTRACT FROM AUTHOR]

Glass is an essential category of materials because of its inherent transparency, which sets it apart from many other material systems. Due to its unique characteristics, radiation shielding applications have begun implementing it, particularly when optical clarity is required. Researchers have been compelled to examine glass materials that offer optimal performance in radiation shielding against high photon energy and particles. The literature has encompassed various papers examining many types of glass and their responses to ranged energy levels. This mini-review aims to demonstrate the glass systems that have been reviewed and their respective radiation shielding characteristics against photon energies. To achieve this objective, the publication numbers for radiation shielding materials and glass were initially collected over several years from the widely utilized Web of Science (WoS) database. Subsequently, the glass systems that were primarily examined in the context of radiation shielding glass investigations were identified and classified as borate (B), germanate (G), phosphate (P), silicate (S), tellurite (T), and waste (W). The current trajectory of these glass systems has been illustrated over the years. After providing a broad description, each glass system was examined using an approach that involved sorting based on the highest-citation and newest-first criteria. Five publications were selected for each way, and then the chemical composition, density, and linear attenuation coefficient at 662 keV were obtained. Furthermore, the Phy-X/PSD software facilitated the comprehension of the attenuation properties of the glass systems at energy levels of 1173 and 1332 keV. Plus, some computations aided in understanding variations in exposure build-up factors (EBF). As demonstrated by the published data, there has been a significant rise in the number of publications on radiation shielding materials and glass investigations, especially in the last five years. In another development, there has been a recent push towards lead-free glass systems, even though inserting PbO into the glass composition can achieve a high-density value, namely higher than 5 g/cm3. Among the several glass systems of interest, T -glass has emerged as a notable choice for photon energies due to its high-density glass formulation while also being free of lead content. The T -glass series had LAC values (at 1173 keV) ranging from 0.28 to 0.35 cm−1, whereas the B , G , P , S , and W - glass series showed changes between 0.13 and 0.36, 0.17 and 0.39, 0.16 and 0.28, 0.16 and 0.35, and 0.12 and 0.25 cm−1 respectively. It is also essential to acknowledge that W - glass systems have gained popularity from sustainability perspective. Yet, W - glass systems have been found effective against low photon energies. Hence, this concise evaluation strongly highlights the significant potential of T -glass and W - glass systems for future research, owing to the facts that both systems facilitate low-melting temperatures, reduced carbon emissions, and easy preparation while also offering promising radiation shielding properties. • Borate, germanate, phosphate, silicate, tellurite, and waste glass systems have been reviewed. • Glass investigations have lately accounted for up to 30% of all radiation shielding material studies. • T -glass has emerged as a notable choice against high photon energies owing to its high density. • LAC 662 keV could be achieved greater than 0.50 cm−1 with tellurite glass as a lead-free option. • Radiation shielding systems made of waste glass can become prominent in future studies. [ABSTRACT FROM AUTHOR]

This paper investigates the influence of ZnCl 2 on the gamma attenuation and radiation shielding properties of tellurite glasses incorporating Bi 2 O 3 and B 2 O 3. Employing Geant4 simulation and XCOM program, the study explores the impact of varying ZnCl 2 content on different gamma attenuation parameters such as linear attenuation coefficient (μ), radiation protection efficiency (RPE), effective atomic number (Z eff), and HVL. Moreover, the relation between these factors and the density of the studied glass system is discussed in details. It is found that the incremental addition of Bi 2 O 3 significantly enhanced the photon attenuation properties of the tellurite glasses involved. The maximum Zeff values are observed at the low energy region between 0.015 and 0.1 MeV with the values of 53.016, 60.133, 65.950, 70.370, and 73.791 for the glass samples namely TBBZC1, TBBZC2, TBBZC3, TBBZC4, and TBBZC5, respectively. Furthermore, the HVL values fall between 0.0016 cm and 4.3546 cm indicates that the current glass system can be utilizes for gamma shielding applications. The results provide insights into the potential enhancement of radiation shielding efficiency in tellurite glasses, contributing valuable knowledge for the development of advanced materials in nuclear safety applications. • Radiation protection of TeO 2 –ZnCl 2 –B 2 O 3 –Bi 2 O glass system. • Significant influence of ZnCl 2 on the radiation shielding. • Monte Carlo simulations are employed. • A good agreement between the theory and the simulation. • TBBZC5 system has a potential use in nuclear and medical applications. [ABSTRACT FROM AUTHOR]

This paper presents the fabrication of glasses with chemical formula [(TeO 2) 0.70 – (ZnO) 0.22 – (PbO) 0.08 ] 1-x (MnO 2) x where x = 0.02, 0.04, 0.06, 0.08 and 0.1 using melt quenching technique. The main objective is to explore the structural, elastic and gamma ray shielding efficiency of the glasses. The study was conducted using density and molar volume measurements, X-ray diffraction analysis, Fourier transform infrared analysis, non-destructive ultrasonic analysis, and theoretical assessment of the glasses' gamma ray shielding efficiency using the Phy-X/PSD software. High density values in the range of 5.611–5.735 gcm−3 and the XRD analysis showed no sharp peak indicating the amorphous nature of the glasses. The FTIR spectra revealed the presence of both TeO 3 and TeO 4 structural units. The values of the elastic moduli microhardness, Debye and softening temperatures, acoustic impedance, diffusion constant, Thermal expansion coefficient and latent heat of melting were studied and discussed among others. Efficiency parameters of radiation shielding such as the coefficients of mass and linear attenuation, effective atomic number, half and tenth value layers, mean free path and effective electron density were calculated theoretically and discussed. Based on the results discussed, the studied MnO 2 doped TeO 2 -PbO-ZnO glasses appeared to be mechanically strong, and thermally stable for radiation shielding applications. Moreso, the glasses appeared to be better in terms of radiation shielding efficiency than commercial concrete materials like serpentine, barite, ferrite, and chromite. • MnO 2 doped TeO 2 – PbO – ZnO glass system were fabricated using melt-quenching technique. • FTIR, XRD, non-destructive ultrasonic analysis/technique, and density & molar volume were used in the measurements and characterization of the studied glasses. • The high-density value in the range of 5.611–5.735 gcm−3 were recorded and Elastic moduli, Softening & Debye's temperatures, thermal expansion coefficient (α p), acoustic impedance (Z), latent heat of melting (ΔH m) and diffusion constant (D i) were studied. • Phy-X/PSD software was used in calculating the radiation shielding parameters such as Linear Attenuation Coefficient (LAC), Mass Attenuation Coefficient (MAC), and others and the results are discussed. • High values of density, elastic moduli, LAC, MAC, and other parameters suggests the glasses possess great potential for radiation shielding application. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive investigation of borate-based glasses doped with BaO, assessing their physical, structural, optical, and radiation shielding properties through experimental and theoretical analyses. XRD patterns reveal the amorphous nature of the prepared glass samples. Density and molar volume values, and FTIR spectra indicate the impact of BaO concentration on the glass matrix, affecting structural properties. Thermal analysis via TGA/DSC reveals improved thermal properties with the substitution of B 2 O 3 with BaO. UV–visible absorption spectroscopy shows a decrease in energy band gap with rising BaO content, suggesting potential non-bridging oxygen formation. Mass attenuation coefficient (μ m) values exhibit an exponential decay trend with photon energy, influenced by photoelectric absorption, Compton scattering, and pair creation. The glasses prepared had, in general, a better μ m values compared to that of concretes and other glass compositions containing barium oxide. Experimental and theoretical (XCOM) results for mean free path (MFP) and half-value layer (HVL) demonstrate close agreement, validating the accuracy of the experimental data. Both MFP and HVL increase with energy and decrease with BaO addition, emphasizing the potential for these glasses in radiation shielding applications. • Borate based glass samples of the composition (70-x)B 2 O 3 –20Bi 2 O 3 –5ZnO–5WO 3 -xBaO; x = 0, 5, 10, 15 and 20 mol% have been successfully prepared by melt-quenching process. • The addition of BaO in the glass system improves its density, thermal and gamma radiation shielding properties. • The study elucidates structural modifications of borate glasses imparted by the doping of BaO. • Non-toxic and environmentally friendly nature, along with effective shielding behavior, of our prepared glass samples makes it a practical solution for gamma shielding applications. [ABSTRACT FROM AUTHOR]

Tellurite glass is a model material having superior features for several applications. It can be considered as a potential host matrix for different oxides, and this paper aims to study the effects of TeO 2 /B 2 O 3 substitution on synthesis, physical, optical and radiation shielding properties of ZnO–Li 2 O-GeO 2 -Bi 2 O 3 glasses produced by melt quenching technique. The physical and optical features of the fabricated glasses were experimentally investigated by determining pivotal parameters such as density, XRD, tellurium ion concentration (N i), linear refractive index (n o), polaron radius (r p) and inter nuclear distance (r i). Moreover, the relative radiation deposition within the glasses was assessed via the attenuation coefficients (e.g. MAC), specific gamma ray constant (ᴦ), total stopping power (TSP), neutron cross sections, and dose rate (D). Our results suggest that both TeO 2 and B 2 O 3 additives have a significant effect on the fundamental properties of the ZnO–Li 2 O-GeO 2 -Bi 2 O 3 glasses. It also found that the lower thicknesses of the present glasses are required to provide the same level of shielding than ordinary, ilmenite, steel scrap, hematic-serpentine, ilmenite-limonite and basalt-magnetite concretes, RS253-G18 and RS360 glass shields. Therefore, presently investigated glasses are promising photon shields in different technological applications of gamma- and x-rays. [ABSTRACT FROM AUTHOR]

In this study, four alloys composed of highly pure elements (lead, zinc, tin and bismuth), named Pb–Zn50, Pb–Sn50, Sn–Zn50 and Sn–Bi50 were prepared by rapid solidification process (RSP) using melt-spun technique. The structural, mechanical properties (elastic and plastic deformations), and microhardness have been investigated and analyzed using X-ray diffraction, tensile test machine, and vickers microhardness respectively. According to results, the yield strength, ultimate tensile strength (UTS), toughness, and Vickers hardness (Hv) were improved due to the advantages of rapid solidification technology including elimination of grain boundary segregation, improvement in alloy homogeneity, refinement of grain size, formation of novel metastable crystalline, rises in the equilibrium solid solubility's of solute elements and reduction in the degree of order. This can be ascribed to reinforcement of Zn and Bi particles, refined β-Sn, Zn and Bi grains that could obstruct the dislocation slipping. In addition, the shielding performance of these alloys for gamma radiation were examined and analyzed utilizing WinXCom software over energy range 0.015–15 MeV. The alloys under study found to be good shielding materials against γ-ray relative to common shielding materials and newly studied materials. The results indicate that the Sn–Bi50 alloy has the highest values of μm, Z eff and Z eq ranging from 0.039 to 81.3 cm2/g, 60.41–73.83, and 64.02–70.793 respectively. While it has the smallest values of HVL (ranging from 8.73E-4 to 1.86 cm) which means that it is the best choice as a γ-ray shielding material. In aspects of neutron attenuation characteristics, the results also indicate that the Pb–Zn50 alloy has the highest value of Σ R (0.133 cm−1) amongst all other alloys, frequently used neutron shielding materials, and recently studied materials. Furthermore, proton (H+1) and alpha particles (He+2) projected range (PR) and mass stopping power (MSP) values have been calculated. It can be concluded that Zn–Pb alloy among the examined samples is superior in terms of shielding against proton and alpha particles. This paper provides a comprehensive examination of the use of lead and the development of new safety lead-free shielding materials in many applications including nuclear medicine. • Conventional and lead-free binary alloys. • Rapid solidification process using melt-spun technique. • Structural features, microhardness and mechanical properties. • X-ray diffraction (XRD), Vickers microhardness and tensile test machine techniques. • X/Gamma-rays, fast neutron, proton and alpha particles shielding features. [ABSTRACT FROM AUTHOR]

In this work, novel efficient epoxy resin based shielding materials enhanced with BN powder against nuclear radiation was proposed. The composites were prepared by using epoxy resin E51, polyamide resin 651 and BN powder. Neutron shielding performance was analyzed by using Evaluated Nuclear Data File, partial density method and a moderated 241Am–Be neutron source. In addition, gamma ray shielding performance and mechanical property were tested by a137Cs gamma ray source and an electronic universal testing machine, respectively. The results indicate that the addition of BN powder could improve the shielding performance for thermal neutron, fast neutron and gamma ray. Neutron shielding performance of prepared composite materials is nearly the same with the variation of densities. Nuclear shielding performance is better than commercial shields (SWX-213, SWX-201 and SWX-261). And the bending strength is greater than 12.78 MPa. In addition, shielding attenuation mechanism for neutron at 10−5–2 × 108 eV is mainly contributed by elastic scattering attenuation interaction produced by H and C from epoxy resin matrix, and absorption attenuation interaction produced by B from BN powder at 10−5–102 eV. • Novel efficient neutron shielding composites were prepared by BN and epoxy resin. • A new perspective of shielding performance analysis was proposed. • Shielding mechanism for neutron shielding was revealed in the paper. • Shielding ability of the prepared composites were better than commercial shields. • Bending strength of the prepared composite materials was greater than 12.78 MPa. [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 research paper, we studied the optical and nuclear shielding efficiency of newly developed BGO glasses with the following compositions (in wt%): 32Bi 2 O 3 –68GeO 2 , 42Bi 2 O 3 –58GeO 2 , 47Bi 2 O 3 –53GeO 2 , 52Bi 2 O–48GeO 2 , 62Bi 2 O 3 –38GeO 2. BGO glasses were prepared by traditional melt quenching method. To obtain the band gap values of fabricated BGO glasses, optical absorption spectra were used for evaluation of optical properties. The mass attenuation coefficients (μ/ρ) were achieved for prepared glasses at 0.015–15 MeV photon energies employing MCNPX Monte Carlo code and WinXcom program. Moreover, broad-range of nuclear shielding parameters for gamma ray, neutrons and charged particles such as mass attenuation coefficient, half value layer, effective atomic number, buildup factors, mass stopping powers, projected ranges, fast neutron removal cross sections and damage factors were calculated. The refractive index is calculated from E opt , As Bi 2 O 3 concentration is enhanced, E opt is also increased as well as the optical electronegativity and consequently the refractive index. In addition, the results showed that BIGE5 glass sample with highest Bi 2 O 3 contribution has excellent nuclear radiation shielding ability among the other fabricated glass samples. [ABSTRACT FROM AUTHOR]

This paper aims to evaluate not only photon and neutron but also proton and alpha shielding effectiveness of barium bismuth borate glasses doped by CeO 2. The mass attenuation coefficients (μ/ρ) of these glasses have been computed utilizing MCNPX (2.6.0) code in a wide energy range of 0.02–20 MeV and compared with the results of WinXCOM software. Afterwards, some photon attenuation parameters such as half-value layer, (HVL), tenth-value layer (TVL), mean free path (MFP), effective atomic number (Z eff), effective electron density (N el), photon transmission factors (TF) and neutron effective removal cross-sections (Σ R) for the cerium oxide substituted barium bismuth borate glasses have been estimated. Using G-P fitting method, exposure buildup factor (EBF) values have been found over the energy range 0.015–15 MeV up to 40 mfp. In addition, Mass stopping power (MSP) and projected range (PR) values have been calculated for proton particles (H1) and alpha particles (He+2). The results exhibit that the density of the glass can be related to the photon and neutron shielding. A10 glass has the highest Σ R values whereas the lowest TF values in gamma and neutron radiation have been observed for A1 sample. A1 and U glasses possess the highest values of Z eff as well as the smallest values of EBF. It can be concluded that A1 and A10 glasses are alternative materials with terms of photon and neutron attenuation, respectively. [ABSTRACT FROM AUTHOR]

Highlights • Effects of high temperature on the gamma ray shielding for HWC were investigated. • The HWC with magnetite aggregate presented the best high-temperature resistance. • The HWC with magnetite aggregate presented the best shielding properties. • High temperature has little effect on the linear attenuation coefficient and HVL. Abstract The results of durability investigation of two heavyweight concretes containing barite and magnetite aggregates are presented in the paper. The concretes, designed for gamma-ray shielding, were subjected to high temperature from the range of 300–800 °C. The effect of temperature on the mass, apparent density, compressive strength, coefficient of gamma-ray absorption and the superficial changes in the structure of the tested specimens were evaluated. The results of testing were compared to the results obtained for the specimens made from the ordinary concrete containing natural aggregate. The influence of temperature on the linear attenuation coefficient has been observed, as well as the strong relation between occurring of the superficial defects in the structure and the properties of the aggregate under high temperature. [ABSTRACT FROM AUTHOR]

Highlights • Investigation of the influence of homogenization on nuclear heating and shielding. • Heterogeneous model with detailed description of the BSM cooling system. • Homogeneous model simplified by removing pipes and introducing mixed materials. • Nuclear heating was calculated for several components and on a fine mesh for both models. • Homogenization tends to underestimate the local heat deposition and overestimates shielding. Abstract The electron cyclotron-heating upper launcher (ECHUL) will be installed in four upper ports of the ITER tokamak thermonuclear fusion reactor. Each ECHUL is able to deposit 8 MW power into the plasma for plasma mode stabilization via microwave beam lines. These beam lines and other components needed for the guidance of the microwaves are mounted into the upper port plug. In order to protect these components and to mitigate radiation leaving the reactor, several shield blocks are also included in the port plugs design. The ECHUL components which are closest to the fusion plasma are heated by the gamma and neutron radiation and therefore will need to be actively cooled. This paper reports on the influence of material homogenization by comparing results obtained in the neutronic analyses performed for the cooling system of the ECHUL blanket shield module (BSM). A small reduction in shielding performance of the BSM was found in the case of a heterogeneous description of the BSM compared to the standard approach of homogenizing the materials of the BSM by removing pipes and cooling circuits for the neutronic analyses. [ABSTRACT FROM AUTHOR]

Radiation interaction parameters are important for exploring the technological relevance of materials in radiation environments. In this research paper, gamma-ray shielding efficacy of GeO 2 +B 2 O 3 +P 2 O 5 +ZnO magneto-optical glasses doped with Tb3+ and coded as GBPZT1-6 for Tb3+ doping concentrations ranging from 20 to 45 mol%, with a 5-mol% increment was investigated using theoretical and Monte Carlo simulation methods. The PHITS code and the Phy-X/PSD software was used to compute the mass attenuation coefficient (MAC) and other interaction quantities of the glasses for 0.015–15 MeV photons. Both methods' MAC data agree to within 2.90% of each other. At 0.015 MeV, the value of MAC is 59.9674 cm2/g, 64.1777 cm2/g, 67.6697 cm2/g, 70.6128 cm2/g, 73.1271 cm2/g and 75.2998 cm2/g for GBPZT1, GBPZT2, GBPZT3, GBPZT4, GBPZT5 and GBPZT6, respectively. The linear attenuation coefficients of the GBPZT glasses changed from 0.1340 to 247.5640 cm−1, 0.1490 to 286.8040 cm−1, 0.1650 to 326.6350 cm−1, 0.1790 to 365.7810 cm−1, 0.1990 to 413.9290 cm−1, and 0.2190 to 463.9450 cm−1 for GBPZT1, GBPZT2, GBPZT3, GBPZT4, GBPZT5, and GBPZT6. Comparatively, the photon attenuation abilities increase linearly as the density and Tb 2 O 3 content of the glass system increased. Hence, GBPZT6 has the highest mass and linear attenuation coefficients, while GBPZT1 has the least. The BPZT glasses have better photon absorbing capacities compared to ordinary concrete and some other conventional shielding materials, thus making them attractive choice in radiation protection functions. • Radiation shielding capacity of germinate glasses is estimated. • Monte Carlo simulations are carried out. • A good agreement between the theory and the simulation. • GBPZT6 glass system has a potential use in nuclear applications. [ABSTRACT FROM AUTHOR]

This paper presents an assessment of gamma radiation shielding performance, specifically in terms of surface dose rate, of concrete containing virgin and recycled coarse aggregates (RCA) to be used for a transportable concrete container for radioactive waste. In order to evaluate radiation shielding performance of the transportable concrete container a numerical simulation method is performed using Monte Carlo N-particle version 6.1 (MCNP6.1). Prior to evaluating radiation shielding performance of the transportable concrete containers, radiation shielding properties of four different concrete mixtures which have two different compressive strengths, 40 and 70 MPa, containing natural coarse aggregate (NCA) and recycled coarse aggregate (RCA), respectively, are assessed using experimental and numerical simulation methods in terms of linear attenuation coefficient ( μ ) to verify the reliability of the numerical simulation method. Density, compressive strength, and static modulus of elasticity tests are conducted to determine the parameters for transportable concrete container design. Based on the physical properties of concrete a transportable concrete container is designed. In order to assess the radiation shielding with respect to the maximum surface dose rate of the concrete containers, three different radioactive wastes are assumed to be loaded in the containers with metal drums and radiation shielding analysis is carried out using MCNP6 simulation code for the four different concrete containers, comparing with the existing carbon steel container. It was found that the results from numerical simulation are in good agreement with the experimentally determined results. In terms of the maximum surface dose rate, all concrete containers showed considerably lower surface dose rate than the existing carbon steel container. [ABSTRACT FROM AUTHOR]

This paper summarizes the results of investigations of hybrid concrete containing scale and granulated lead–zinc slag wastes as substitutes for sand. Specifically, scale and granulated lead–zinc slag wastes are completely substituted for natural sand in concrete. The aim of this study was to investigate the effects of these waste materials on gamma radiation shielding and on the compressive strength properties of concrete. The linear attenuation coefficient (μ, cm −1 ) and compressive strength of the samples were measured experimentally and calculated, and the experimental values were subsequently compared with those of conventional concrete. The results clearly showed that hybrid scale waste/granulated lead–zinc slag waste concrete (Sc/Glzs-C) has better radiation shielding and compressive strength properties than conventional concrete. An additional objective of this study was to calculate the thickness of the hybrid concrete shield to be used instead of conventional concrete. The results showed that the produced concrete demonstrates better radiation attenuation properties with thinner thickness compared to conventional concrete. As a result, the new concrete containing scale waste and granulated lead–zinc slag waste is suitable for gamma radiation attenuation. [ABSTRACT FROM AUTHOR]

Four sulfide compounds' attenuation features of gamma-ray (Ag 2 ZnSnS 4 , Ag 2 ZnSnSe 4 , ZnS, and Ag 2 S) were described in this paper by a new software Phy-X/PSD. We calculated radiation attenuation parameters for the selected samples for a broad range of energies (0.015–15 MeV), including linear attenuation, the mean free path, the half-value layer, and total atomic and electronic cross-sections. The effective atomic number and the effective conductivity were also analyzed to investigate the radiation attenuation features. Also, the analyzed samples' buildup factors were studied. The samples' parameters were compared to materials frequently used to shield against radiation, including ferrite, chromite, barite, magnetite, and RS (253 G18, 360, 520) glass. Due to MFP and HVL values, Ag 2 S has better attenuation features than all the other samples utilized in the comparison. Fast neutron removal cross-sections (FNRCS) were also studied, and the best neutron attenuation composite among the samples under study, according to the FNRCS data, is Ag 2 S (0.116 cm−1). [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 study, aims to investigate on non-traditional tellurite glasses and conducted to study structural, mechanical, acoustic and parameters of gamma radiation shielding (eg. Liner Attenuation Coefficient (LAC), Half Value Layer (HVL), micro-hardness (H)), for the Ternary TeO 2 /TiO 2 /B 2 O 3 glasses with different molar composition. Important parameters used for radiation shielding of the glass samples were investigated by both Monte Carlo simulation codes (MCNP and Geant4) and Phy-X/PSD software, in the 0.284, 0.347, 0.511, 0.662, 0.826, and 1.173 MeV photon energies. As a result, the values of Elastic module, structural, acoustic parameters and fractal Bond were found in this paper. Our calculation confirmed that samples (with the most TeO2 content almost 80 mol% and the least B2O3 amount around 10 mol%) represented the least Molar oxygen volume (11.980 cm3/mol) and the most Oxygen packing density (83.465 mol/L). The simulated results, show that the HVL for the TT and TB glass samples are below the level of other examples, and the TTB2 has the highest HVL at high energy (1.173 MeV). Also, TT and TB have higher MAC and TTB2 has lower MAC. [ABSTRACT FROM AUTHOR]

The design and fabrication of shielding materials with good heat-resistance and mechanical properties is a major problem in the radiation shielding field. In this paper, based on gamma ray and neutron shielding theory, a continuous carbon-fiber reinforced Sm 2 O 3 /polyimide gamma ray/neutron shielding material was fabricated by hot-pressing method. The material's application behavior was subsequently evaluated using neutron shielding, photon shielding, mechanical tensile, and thermogravimetric analysis–differential scanning calorimetry tests. The results show that the tensile strength of the novel shielding material exceeds 200 MPa, which makes it of similar strength to aluminum alloy. The material does not undergo crosslinking and decomposition reactions at 300 °C and it can be used in such environments for long periods of time. The continuous carbon-fiber reinforced Sm 2 O 3 /polyimide material has a good shielding performance with respect to gamma rays and neutrons. The material thus has good prospects for use in fusion reactor system and nuclear waste disposal applications. [ABSTRACT FROM AUTHOR]

The high mass density that often characterize TeO 2 -based glasses makes them potentially useful in radiation shielding applications. In this paper, three ternary glass types defined by the chemical formula: (90 − x)TeO 2 - x ZnO-3La 2 O 3 for x = 35 (TZL-A1), 15 (TZL-A2), and 5 mol% (TZL-A3) were considered for optical and gamma radiation absorption study. The reflection loss (RLoss), metallization criterion (M), optical transmission (TOpt.), optical dielectric constant (εoptical), and static dielectric constant (εSta.) were the optical parameters estimated for the glasses. Also, gamma radiation shielding ability of the glasses were assessed through computation of mass attenuation coefficient μ m for energies 0.015 − 15 MeV using FLUKA simulations and XCOM computation. The RLoss is 0.105, 0.117 and 0.121 for TZL-A1 – TZL-A3, respectively while TOpt. is 0.809, 0.791 and 0.784 in the same order. The metallization criterion (M) is 0.513, 0.488 and 0.478 for TZL-A1, TZL-A2 and TZL-A3, respectively. The optical dielectric constant (εoptical) of TZL-A glasses is 2.849, 3.149 and 3.272 while the static dielectric constant (εSta.) is 3.849, 4.149 and 4.272 for TZL-A1, TZL-A2 and TZL-A3, respectively. Also, The value of μ m varies between 0.03309 and 47.90855 cm2/g, 0.03332 and 46.67536 cm2/g, and 0.0333 – 43.12055 cm2/g for decreasing ZnO content accordingly. Computed value of the Z eff falls between 22.74 and 49.74 for TZL-A1, 23.34–51.07 for TZL-A2 and 23.61–51.59 for TZL-A3. Other computed photon shielding quantities shows that higher TeO 2 content improves the shielding ability of the glasses. The present glasses showed superiority compared to some existing and popular shields such as ordinary concrete, commercial RS-253 and RS-360 glass shields. These glasses thus present better alternative materials which could be used in the implementation of an efficient photon collimator or biological shields in laboratories, industries, and medicine where gamma radiation are adopted for diverse applications. [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]

Abstract: A new computer code named as SHIELD DESIGN has been developed in Visual Basic Version 6.0 for precise estimation of shielding thickness in gamma ray shielding designs. In the conventional forward calculations using point kernel method, the sources and geometry are specified along with the shield thickness to obtain dose rates at desired locations. But in this code, a new computational technique based on inverse calculation and iterative procedures have been employed to estimate the shield thickness using the dose rate criteria as input information. This new technique enables quicker and easier way of shield design optimization by computing shield thickness required in a single run whereas in the forward shield design optimization method, dose rate computations need to be carried out for various shield thicknesses. The shielding thickness arrived with this code provides a first hand information to the designer to carry out forward calculations for accurate optimization. Also, the code is very useful to regulators for quicker verification of shield calculations submitted by the designers for approval. Further, various options available in this code extend its flexibility and user friendliness. This paper briefly presents the development and validation of the code, SHIELD DESIGN. The validation has been carried out by performing analyses of the gamma shielding design for some standard problems. The results were compared with those of renowned forward calculations, experimental measurements, NCRP-51 benchmarks and other gamma radiation shielding utilities like RAD-PRO and satisfactory agreement was observed. These validation tests demonstrate the precise estimation of shield thickness. [Copyright &y& Elsevier]

Abstract: This paper presents an approach based on generalized feed-forward neural network (GFFNN) to compute exposure buildup factors (BD ) for point isotropic sources in infinite homogeneous media at energies varying from 0.03MeV to 15MeV and up to depths of 10 mean free paths (mfp). The results obtained by using the proposed model have been compared with the ANSI standard data, the calculations by use of EGS4 Monte Carlo code and Invariant Embedding (IE) Method for water, iron, lead and concrete. The comparisons have shown that the GFFNN model improved BD estimation with respect to the other methods, particularly for lead and concrete. [Copyright &y& Elsevier]

Abstract: The GERmanium Detector Array (GERDA) experiment will search for neutrinoless double beta decay of and is currently under construction at the INFN Laboratori Nazionali del Gran Sasso (LNGS) in Italy. The basic design of GERDA is the use of cryogenic liquid and water of high purity as a superior shield against the hitherto dominant background from external gamma radiation. In this paper we show by Monte Carlo simulations and analytical calculations how GERDA was designed to suppress this background at to a level of about . [Copyright &y& Elsevier]

Abstract: This paper summarizes the results from the investigations carried out on fiber reinforced concrete with steel fibers, lead fibers and a combination of the two (hybrid fibers). The intent of this research was to investigate the effect of the two types of fibers on mechanical and radiation shielding properties of concrete. Compressive strength, split tensile strength and flexural toughness were among the mechanical properties investigated and radiation shielding to gamma rays was investigated by comparing the attenuation provided by different types of concrete against each other and against blank readings without attenuation. The results clearly showed that the hybrid fibers showed a significant enhancement in both mechanical and radiation shielding properties. [Copyright &y& Elsevier]

Abstract: Beyond the Earth''s atmosphere, galactic cosmic radiation (GCR) and solar energetic particles (SEPs) are a significant hazard to both manned and robotic missions. For long human missions on the lunar surface (months to a year) a radiation shelter is needed for dose mitigation and emergency protection in case of solar events. This paper investigates the interaction of source protons of solar events like those of February 1956 that emitted many fewer particles with energies up to 1000MeV and of the October 1989 event of lower protons energy but higher fluence, with the lunar regolith and aluminum shielding of a lunar shelter. The shelter is 5m in diameter and has a footprint of 5×8m and a 10cm thick aluminum support structure, however, actual thickness could be much smaller (∼1–2cm) depending on the weight of the regolith shielding piled on top. The regolith is shown to be slightly more effective than aluminum. Thus, the current results are still applicable for a thinner aluminum structure and increased equivalent (or same mass) thickness of the regolith. The shielding thicknesses to reduce the dose solely due to solar protons in the lunar shelter below those recommended by NASA to astronauts for 30 day-operation in space (250mSv) and for radiation workers (50mSv) are determined and compared. The relative attenuation of incident solar protons with regolith shielding and the dose estimates inside the shelter are calculated for center seeking, planar, and isotropic incidence of the source protons. With the center seeking incidence, the dose estimates are the highest, followed by those with isotropic incidence, and the lowest are those with the planar incidence. [Copyright &y& Elsevier]

Abstract: The saturation of South Korea''s at-reactor (AR) spent fuel storage pools has created a need for additional spent fuel storage capacity. The Korea Hydro & Nuclear Power Company is planning to construct a MACSTOR-400 facility composed of reinforced concrete. In concrete structures, cracks occur due to thermal stress, hydration heat, weather, load and other reasons, and shielding performance changes according to the event by crack. However, there are no researches providing the allowable crack for shielding. This paper presents estimating the effect of concrete spalling on gamma-ray shielding performance in MACSTOR-400 based on an FEM simulation. When the cover thickness is under 10cm, it is estimated that spalling will be formed. Generally, because cover thickness is under 10cm in the concrete structure, it is estimated that spalling will be formed in MACSTOR-400. If the thickness of wall in MACSTOR-400 is over 100cm, it is estimated that surface dose rate will be maintained within the radiation safety standards under any conditions related to crack effect. The results of this study may be used for developing standards for radiological safety in shielding structures, especially in relation to the shielding margin. [Copyright &y& Elsevier]

The nuclide-specific dose rate constant, formerly called gamma ray constant, is one of the most important quantities in practical radiation protection dosimetry. For radiation sources with known radionuclide composition and activity, the expected dose rates at various distances can easily be calculated with reasonable approximations. In addition, they serve as a planning basis for the design of shielding of radiation application rooms and facilities. In this study, dose rate constants were calculated using the most recent conversion coefficients and the most suitable spectral data for more than 400 radionuclides using different calculation approaches. In addition this paper provides a critical review of currently published dose rate constants for the ambient dose equivalent H ∗ (10). [Display omitted] • In a novel approach, x-rays are considered for dose rate constants and applied for the calculation of 400 radionuclides. • Comparison of different approaches for calculating dose rate constants. • Comparison of different conversion coefficients published bei IRCU 57, ICRP 74 and ISO 4037-3. • Evaluation of published dose rate constants for radionuclides in different energy ranges. • Investigation of possible causes for the discrepancies between the published data. [ABSTRACT FROM AUTHOR]

In this paper the calculation of direct heat generation and energy savings due to the penetration of 1.37 and 2.75 MeV energy photons, emitted from a Na-24 radiation facility, through double layer shielding slabs of aluminium, steel and lead is described. A comparison is being made among six different shielding material combinations in order to assess the optimum shield related to the maximum energy captured due to γ-rays penetration through the combined shielding materials. [Copyright &y& Elsevier]

• Mechanic and gamma-ray shielding properties of concrete are investigated. • Sixteen heavy-weight concrete mixes investigated for radiation shielding performance. • Ferrophosphorous had more efffect on attenuation of radiations than barite. This paper assesses the gamma radiation shielding performance of concrete containing heavy-weight materials partially and fully replacing the cement and fine aggregate. Metal dust waste was used as the cement replacement material in order to improve radiation protection, while high-density fine aggregates including copper slag, barite, and ferrophosphorus were also used. Various high-density concrete samples were prepared by using metal dust waste as a cement substitution and also using several types of high-density material as fine aggregate. A total of sixteen concrete mixtures were developed using various volumes of metal dust waste and high-density fine aggregate types and fractions. These concrete mixtures were tested for their density and compressive strength. Gamma attenuation measurements were taken with these mixtures at three gamma energies of 0.66, 1.17, and 1.33 MeV with the obtained results compared with the simulation method performed using WinXCom software. The results of the present study indicate that the density of hardened concrete was enhanced to a maximum of 42.49%, proportional to higher replacement ratios. Using metal dust waste as a substitute material caused the compressive strength to decrease even though their density was enhanced. For the fine aggregate replaced by heavy-weight materials, their effects on the compressive strength were dependent upon the replacement material. The observed linear attenuation coefficient was observed to be in the range of 0.128 cm−1 to 0.260 cm−1, dependent upon the concrete compositions and gamma ray energies. The consistency of the linear attenuation coefficient from the experimental and simulation results shows the coefficient of determination of 0.728, 0.855, and 0.907 for photon energies of 0.66, 1.17, and 1.33 MeV, respectively. The maximum reduction of the tenth value layer, defined as the thickness of a shielding material that reduces the radiation level by one tenth of the initial level, was observed to be around 25% from the sample with metal dust waste and ferrophosphorus cooperating substitution. [ABSTRACT FROM AUTHOR]

This paper discussed the neutron and gamma rays shielding characteristics of PVB/Bi 2 O 3 @BaZrO 3 nanocomposite films. The EDX, FTIR, and XRD patterns affirmed the successful preparation of the nanocomposite films. The increase of the BaZrO 3 @Bi 2 O 3 content reduces the films' optical bandgap. While, the Urbach energy values of PVB/Bi 2 O 3 @BaZrO 3 nanocomposite films enhanced with increasing Bi 2 O 3 @BaZrO 3 content. Further, we examined the mechanical characteristics of the nanocomposite films. Besides, Phy-X/PSD software was used to compare the experimental gamma-ray attenuation data with theoretical values. Overall, the PVB/(Bi 2 O 3 @BaZrO 3) composite films are suitable as gamma radiation shielding materials. [Display omitted] • The PVB/(Bi 2 O 3 @BaZrO 3) x nanocomposite films were prepared by solution casting technique. • The optical bandgap of the nanocomposite films decreased with increasing the filler content. • The mechanical characteristics of the nanocomposite films were examined. • The composite films displayed significant improvement in the gamma rays shielding capability. [ABSTRACT FROM AUTHOR]

This paper presents data on the study of changes in the structural, optical, and gamma radiation shielding characteristics of TeO 2 –MoO–Bi 2 O 3 ceramics doped with СеО 2. Doping was carried out by adding CeO 2 powder to the composition of ceramics during mixing in the following molar proportions of 0.05, 0.10, 0.15, 0.20, and 0.25 mol %. Using the method of X-ray phase analysis, the dynamics of phase transitions was established: Bi 6 Te 2 O 13 /Bi 4 MoO 9 → Bi 4 MoO 9 /CeTe 2 O 6. It was found that an increase in the concentration of the dopant leads to a change in the content of the phases, followed by the equilibration of the Bi 4 MoO 9 and CeTe 2 O 6 phases at a dopant concentration of 0.20 and the dominance of the CeTe 2 O 6 phase at a concentration of 0.25. During the determination of optical characteristics, it was found that doping leads to sharp change in the fundamental absorption edge and a decrease in the E g value from 2.27 eV to 1.87 eV, as well as the appearance of two absorption bands with energies of 1.72 eV and 2.39 eV. During the determination of gamma radiation shielding characteristics, it was found that an increase in the concentration of CeO 2 leads to an increase in gamma radiation shielding efficiency exceeding 50% for dopant concentrations above 0.15 M in the composition of ceramics. • Shielding characteristics of TeO 2 –MoO–Bi 2 O 3 ceramics doped with СеО 2. • Doping with CeO 2 oxide leads not only to an increase in the degree of crystallinity and density of ceramics. • The dependence of the change in the band gap and the density of dislocations in ceramics. • Radiation protection efficiency versus dopant concentration. [ABSTRACT FROM AUTHOR]

In this paper, attempts are made to use waste plastics to make a novel Waste Polymer Incorporated Concrete (WPIC) mixes for gamma and neutron radiation shielding purposes. These mixes are achieved by simultaneous incorporation of waste polymeric material and high density fine and coarse aggregate components from iron industry in place of conventional ingredients. The results have indicated that the waste plastics along with by-products of iron industry can be conveniently used to make concrete mixes which have acceptable compressive strength characteristics and significantly enhanced shielding capabilities with respect to both gamma and neutron radiations. [Display omitted] • HDPE based waste polymeric material is used to make novel shielding concrete for gamma and neutron radiation shielding. • Mixes are achieved by simultaneous incorporation of waste polymeric material and high density fine and coarse aggregates. • Significant reductions in flux and dose transmissions and significant improvements in attenuation coefficients are observed. • Waste polymers with by-products of iron industry are used to make novel gamma and neutron radiation shielding concrete. [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]

In the modern world, great attention is paid to methods of protection against the negative effects of ionizing radiation. One of the promising solutions to this problem is the creation of radiation-resistant ceramics or glasses based on Bi 2 O 3 –WO 3 –TeO 2 , which have a high radiation resistance and absorbency of various types of ionizing radiation, including gamma, X-ray, and electron radiation. This paper presents the results of the study of the synthesis of Bi 2 O 3 -TeO 2 -WO ceramics, phase transformations and changes in optical and structural characteristics as a result of thermal annealing. The synthesis of ceramics was carried out using the methods of mechanochemical synthesis and thermal sintering in the range from 300 to 800 °C. Using the method of X-ray phase analysis, it was found that as a result of an increase in the sintering temperature, the following phase transformations occur: WO 3 /Bi 2 Te 4 O 11 → WO 3 /Bi 2 Te 2 W 3 O 16 → Bi 2 Te 2 W 3 O 16 → Amorphous glass similar state. The efficiency of gamma radiation shielding with energy of 130 keV by Bi 2 O 3 -TeO 2 -WO 3 ceramics is shown. It was found that for ceramics with a thickness of 0.5 mm, the intensity of gamma radiation can be reduced to 30–70%, depending on the phase composition of the ceramics. • Phase transformations occur: WO 3 /Bi 2 Te 4 O 11.→ WO 3 /Bi 2 Te 2 W 3 O 16 → Bi 2 Te 2 W 3 O 16 → Amorphous glass similar state. • The intensity of gamma radiation can be reduced to 30–70%, depending on the phase composition of the ceramics. • The change in the value of the band gap and linear refractive index. • The prospects of using the selected synthesis conditions to increase the shielding efficiency. [ABSTRACT FROM AUTHOR]

This paper presents an experimental study on the performance of shielding refractory concretes containing new types of cements for use in the radiation protection technology. Three concretes with corundum aggregate and special refractory inorganic cements belonging to the CaO–Al 2 O 3 , SrO–CaO–Al 2 O 3 –ZrO 2 , SrO–Al 2 O 3 and BaO–CaO–Al 2 O 3 –ZrO 2 systems were tested. The products formed in the hydration of these binders were detected by SEM-EDS. The linear attenuation coefficients obtained from measurements with γ quanta emitted by the following sources: 22Na, 137Cs, 60Co, 133Ba and 152Eu in the range of 80–1408 keV were determined twice, firstly after casting and drying (110 °C) of concretes, and secondly after sintering at 1400 °C. Especially, this work fills the gap in the literature providing the gamma rays attenuation properties of cement-containing heat-resistant corundum concretes in the energy region between 779 keV and 1112 keV. The experimental setup equipped with the ORTEC GMX25P4-70 High Purity Germanium detector (HPGe) cooled with liquid nitrogen was used for determination of the gamma-ray linear attenuation coefficients of new materials. The role of the cement on the compressive and bending strengths, pore structure (mercury intrusion porosimetry), phase composition (XRD, FT-IR) and microstructure (SEM-EDS) of heat-treated concretes was reported. It was found that the incorporation of Sr or Ba and Zr elements with cements improved the attenuation properties of corundum-based concretes, in comparison to the concretes containing Ca. The doping alkaline earth elements i.e. Sr and Ba were chemically bonded within both hydraulic matrix of green concretes and ceramic matrix formed in concrete through sintering at 1400 °C. Hence, these materials with gamma radiation shielding capacity are designed for special construction applications. • Ba- and Sr-doped cements belonging to the CaO-Al 2 O 3 -ZrO 2 system were proposed for heavy concretes. • Mechanical, physical and gamma-ray attenuation properties of (CaO,SrO,BaO)-Al 2 O 3 -SiO 2 -ZrO 2 concretes are presented. • Difference in gamma ray attenuation properties of green and sintered castables was highlighted. • Radioactive sources 22Na, 137Cs, 60Co, 133Ba and 152Eu were used in this study. • Sr and Ba elements were chemically bonded within both hydrated cement matrix and the ceramic matrix of concrete. [ABSTRACT FROM AUTHOR]

This paper focuses on the role of antimony oxide (up to 15 wt%) in the physical, structural, optical, and radiation attenuating characteristics of boro-bismuth glasses within B 2 O 3 -20Bi 2 O 3 - 20Na 2 O 2 - Sb 2 O 3 system. This glass system was prepared by melting at 1250°C and quenching into water. The physical properties were studied by measuring the density, molar volume, and x-ray diffraction for the prepared glass system. The structural features were investigated by determining packing density, passion ratio, oxygen packing density, and oxygen molar volume. The optical attributes were explored by evaluating bandgap, Urbach energy, refractive index, and other related parameters such as dielectric constant, reflection loss, molar polarizability, molar refractivity, optical dielectric constant, optical electronegativity, electron polarizability, optical basicity, metallization, and cut-off wavelength. On the other hand, the shielding properties of the prepared glasses were studied against different types of radiation such as gamma, electron, proton, and neutron beams. The radiation studies were carried out by utilizing Geant4 simulations and the newly developed Phy-X/PSD program. The radiation-shielding characteristics of the present samples were examined in terms of mass attenuation coefficient, stopping power, half value layer, removal cross section, mean free path, and effective atomic number of gamma, electron, and proton beams. The results showed that antimony oxide content had an important influence on the shielding ability against all of the types of radiations. Additionally, the obtained results were compared with those of standard radiation shields. It can be concluded that the present glasses have a promising future to be used as radiation shielding material, wherein the antimony oxide concentration can be balanced according to the desired application. [ABSTRACT FROM AUTHOR]

Gamma ray is an energetic ionising radiation that can damage living cells as it slows down and transfers its energy to surrounding cells. Lead and concrete have been used as radiation shielding materials. However, it shows that lead toxicity is an important environmental disease and its effects on the human body are devastating. Thus, there is an urgent need to find a sustainable radiation shielding material to safeguard the human and the environment from destructive impact of radiation. High atomic number and high-density materials such as tungsten and concrete are the best effective characteristics of radiation shielding materials. There are numerous experimental and theoretical works were performed on radiation shielding materials. This paper presents a review on the application of lead as radiation shielding material, current safety issues related to lead, current work on radiation shielding material and recent development of new lead-free shielding materials in nuclear medicine. • Lead has been used as a radiation shielding material for radiation protection. • However, lead introduces insidious hazard to human health due to formation of dust particles that affect biochemical systems. • New lead-free materials can replace lead for radiation protection in nuclear medicine. • Recent development of new lead-free radiation shielding materials in nuclear medicine. [ABSTRACT FROM AUTHOR]