Hydrotalcites (HTs), recognized for their eco-friendly synthesis, layered structure, and exceptional ion-exchange capacity, offer significant potential as functional additives in cementitious systems. Most previous studies used different types of HT based on varying the kinds of di- or tri-valent cations during the preparation process, but they did not change the ratio between them. Accordingly, this study tailored three Mg-Al-CO₃-based HTs with varying Mg: Al ratios (1:1, 2:1, and 3:1, designated HT1, HT2, and HT3) and incorporated them at 1 wt% into ordinary Portland cement (OPC) pastes. The effects of HTs on setting time, workability, and compressive strength were evaluated. Phase composition, textural properties, and microstructure of reference and HT-modified pastes were characterized using XRD, BET/BJH analyses, and SEM/EDX. Additionally, gamma-ray shielding performance against Cs-137 (661.64keV) was assessed by determining the linear attenuation coefficient (µ) and half-value layer (HVL). Results reveal that HTs accelerate setting, slightly reduce workability, enhance compressive strength, and significantly improve radiation shielding. Among the tailored HTs, HT1 exhibited superior performance, achieving the highest compressive strength (88.8MPa at 28 days) and greatest shielding efficiency, with µ increased by 112.5% and HVL reduced by 52.9% compared to OPC. These improvements are attributed to HT1's high surface area, amorphous/mesoporous nature, and its role as a nucleation site and filler, leading to a dense microstructure. Furthermore, incorporating HTs provides an environmentally sustainable approach for producing high-performance cementitious materials with enhanced mechanical and radiological properties, supporting industrial applications in construction and nuclear safety.

BackgroundBeam hardening is an unavoidable phenomenon in polychromatic CT systems, where lower‐energy photons are preferentially absorbed as x‐rays pass through materials such as tissue, bone, and metal. This energy‐dependent attenuation, which conflicts with the monochromatic assumption in filtered back‐projection (FBP), produces artifacts that degrade CT image quality and diagnostic accuracy.PurposeThis study aims to quantitatively estimate the mean energy corresponding to the beam‐hardened projection data along each x‐ray path and to employ this mean energy to convert energy‐dependent projections into beam‐hardening–corrected data. The effectiveness of the proposed mean energy–based correction method is verified through numerical simulations.MethodsTo mathematically determine the mean energy, a polynomial equation is derived whose solution represents the mean energy. Based on the Beer–Lambert law, the CT system is formulated as an energy‐integrated model incorporating the x‐ray spectrum and the linear attenuation coefficient of the scanned object. By applying the mean value theorem for integrals and performing power series expansions of the energy‐dependent components of the attenuation coefficient—such as Compton scattering and photoelectric absorption—a polynomial equation with respect to the mean energy is obtained. Solving this equation yields the mean energy, which is subsequently employed to generate beam‐hardening—corrected projection data.ResultsA novel correction method based on the computed mean energy is proposed to transform energy‐dependent projection data into corresponding monochromatic data. Numerical simulations conducted on various models demonstrate that the proposed approach effectively corrects beam‐hardened projection data and substantially reduces beam‐hardening artifacts in reconstructed CT images. The method maintains accuracy even in complex scenarios involving multiple overlapping materials and metallic objects, without a significant increase in computational cost. Furthermore, the robustness of the proposed correction technique is confirmed under varying x‐ray spectra, verifying its potential applicability to practical CT imaging.ConclusionsGrounded in physical modeling and analytical approximation, this study presents a mathematical formulation for estimating the mean energy corresponding to beam‐hardened projection data and develops a correction method that effectively mitigates beam‐hardening artifacts. The results highlight the potential of the proposed mean energy—based correction as a practical and computationally efficient solution for improving CT image quality. However, as this study primarily focused on the computation of mean energy as an indicator of beam‐hardening severity, further research is required to apply and validate the proposed method using experimental and clinical data for comprehensive verification of its practical applicability.

Polymer-based composites have emerged as promising materials for radiation shielding; however, most previous studies have focused on mono- or binary-oxide systems, overlooking the synergistic interactions among multiple oxides with varying atomic numbers. This work develops advanced polymethyl methacrylate (PMMA)-based composites reinforced with a complex combination of metal oxides to enhance gamma-ray attenuation. The composites were formulated with the composition [PMMA: X% Bi2O3, (30 − X) % MoO3, 40% B2O3, 20% SiO2, 9% Na2O, and 1% Fe2O3], where X = 5%, 10%, 15%, and 20%. Mechanical mixing was employed to achieve uniform dispersion of the oxide fillers within the PMMA matrix. Structural and morphological analyses were performed using X-ray diffraction (XRD) and scanning electron microscopy (SEM), while radiation shielding performance was evaluated in terms of transmittance (T), absorbance (A), and the linear attenuation coefficient (μ). The XRD results revealed an amorphous PMMA matrix with partial crystallinity induced by oxide incorporation. SEM micrographs confirmed homogeneous particle dispersion and improved surface morphology, especially for the composite containing 20% Bi2O4 (S4). This sample exhibited the lowest transmittance and highest linear attenuation coefficient, demonstrating superior shielding efficiency. These findings underscore the crucial influence of oxide composition and microstructural uniformity on the radiation attenuation capability of polymer–oxide composites.

This study investigated the effect of adding BaSO4 to polypropylene (PP) and high-density polyethylene (HDPE) polymer materials at 5%-10%-15% by weight on the photon shielding of these materials depending on the changing BaSO4 ratio. Phy-x/PSD and Xcom programs were used during the analysis. In addition, the percentage differences between the two programs were investigated. Moreover, scanning electron microscope (SEM) and X-ray diffractometer (XRD) analyses of BaSO4 powder material and XRD, SEM, reduced total reflectance, differential thermal analysis, thermogravimetric analysis, and differential scanning calorimeter characterization analyses of the polymer materials were performed. As a result, the study revealed that the difference between the Xcom and Phy-x programs was less than 1%. The photon shielding properties of the PP and HDPE materials improved depending on the increasing BaSO4 ratio. Due to its higher density, HDPE exhibited better photon shielding performance than PP. The shielding properties of the HDPE material were better. The 0.005888 MeV (55Fe) energy was also 8.688 cm−1, 31.401 cm−1, 61.329 cm−1, and 98.471 cm−1 linear attenuation coefficient (LAC) values for the P1, P2, P3, and P4 coded samples on the order of 8.688 cm−1, 31.401 cm−1, and 98.471 cm−1 LAC values, while the H1, H2, H3, and H4 coded samples were on the order of 9.387 cm−1, 33.387 cm−1, 64.462 cm−1, and 102.613 cm−1 LAC values. At photon energies of 0.005888 MeV and 15 MeV, the half-value layer values of the PP, PP + 5% BaSO4, PP + 10% BaSO4, and PP + 15% BaSO4 materials had thickness values that varied between 0.080 to 43.796 cm, 0.022 to 34.622 cm, 0.011 cm to 28.266 cm, and 0.007 to 23.631 cm, respectively. The HDPE, HDPE + 5% BaSO4, HDPE + 10% BaSO4, and HDPE + 15% BaSO4 materials had thickness values that varied between 0.074 to 40.535 cm, 0.021 to 32.562 cm, 0.011 to 26.892 cm, and 0.007 to 22.677 cm, respectively. The materials produced by reinforcing the polymer materials with BaSO4 are expected to be promising materials in application areas such as hospitals, agriculture, industry, etc. where low photon energy emissions occur due to their lightness and nontoxicity.

Lightweight, lead-free polymer–mineral composites have attracted increasing interest as radiation-attenuating materials for applications where reduced mass and environmental compatibility are required. In this work, the -ray attenuation behavior of poly(ether ether ketone) (PEEK) reinforced with natural palygorskite and pumice was evaluated at filler concentrations of 10–40 wt%. Photon interaction parameters, including the linear attenuation coefficient (), half-value layer (HVL), mean free path (), and effective atomic number (), were computed over the energy range 15 keV–15 MeV using the Phy-X/PSD platform and validated through full Geant4 Monte Carlo transmission simulations. At 15 keV, increased from for pure PEEK to and for the 40 wt% palygorskite- and pumice-filled composites, respectively, reducing the HVL from 0.69 cm to 0.24 cm and 0.11 cm. The corresponding values increased from 6.5 (pure PEEK) to 9.4 (40 wt% palygorskite) and 15.3 (40 wt% pumice), reflecting the influence of higher-Z oxide constituents in pumice. At higher photon energies, the attenuation curves converged as Compton scattering became dominant, although pumice-filled PEEK retained marginally higher and shorter up to the MeV region. These findings demonstrate that natural mineral fillers can enhance the photon attenuation behavior of PEEK while retaining the known thermal stability and mechanical performance of the polymer matrix as reported in the literature, indicating their potential use as lightweight, secondary radiation-attenuating components in medical, industrial, and aerospace applications.

Concrete plays a critical role in nuclear power plants (NPPs) as structural material and radiation shielding. Severe defects during construction of NPP concrete could lead to catastrophic leakages. Therefore, cement plaster propably with acceptable radiation protection could be a good solution as a repairing technique. Thus, this study investigates the mechanical and radiation shielding properties of non-conventional cementitious plaster incorporating magnetite powder as a partial/full replacement for traditional sand. ​Five cement plaster mixtures were proposed with varying proportions of magnetite powder and sand, in which their mechanical and radiation attenuation properties were analyzed. Experimental evaluations including workability, density, compressive strength, and gamma-ray attenuation were investigated. Furthermore, γ-ray and fast neutron shielding has been evaluated using software programs such as EpiXS, NXCom, and MRCsC. Results showed that incorporating magnetite powder in cement plaster production lowers the compactness of the matrix by up to 46.2%. Consequently, the compressive strength was generally decreased by up to 65.4% with increased magnetite content. However, the density of the plaster was increased by up to 48.7% compared to traditional cement plaster. Furthermore, owing to increased density, the radiation shielding efficiency of magnetite cement plaster was generally enhanced. Cement plaster with 100% magnetite content achieved superior linear attenuation coefficient (LAC) for gamma rays with 264% increase at 0.01 MeV and 43% increase at 10 MeV compared to the traditional sand plaster. Also it acquired better fast neutron shielding performance, with a macroscopic removal cross-section (ΣR) of 0.1056 cm⁻¹ (11% increase) compared to the conventional plaster. ​This research highlights the potential of utilizing magnetite-cement plaster with enhanced radiation shielding properties for repair and maintenance strategies of NPP structures. With the achieved gamma and neutron shielding properties, such material can significantly improve safety, durability, and longevity of nuclear power plant structures.

This study evaluates lead-free high-density polyethylene (HDPE) composites reinforced with high-Z oxides (Bi2O3, WO3, Gd2O3, TeO2, and a Bi2O3/WO3 hybrid) as lightweight materials for gamma-ray and fast-neutron shielding. A hybrid computational framework combining Phy-X/PSD with Geant4 Monte Carlo simulations was used to obtain key shielding parameters, including the linear and mass attenuation coefficients (μ, μ/ρ), half-value layer (HVL), mean free path (MFP), effective atomic number (Zeff), effective electron density (Neff), exposure and energy-absorption buildup factors (EBF, EABF), and fast-neutron removal cross section (ΣR). The incorporation of heavy oxides produced a pronounced improvement in gamma-ray attenuation, particularly at low energies, where the linear attenuation coefficient increased from below 1 cm−1 for neat HDPE to values exceeding 130–150 cm−1 for Bi- and W-rich composites. In the intermediate Compton-scattering region (≈0.3–1 MeV), all oxide-reinforced systems maintained a clear attenuation advantage, with μ values around 0.12–0.13 cm−1 compared with ≈0.07 cm−1 for pure HDPE. At higher photon energies, the dense composites continued to outperform the polymer matrix, yielding μ values of approximately 0.07–0.09 cm−1 versus ≈0.02 cm−1 for HDPE due to enhanced pair-production interactions. The Bi2O3/WO3 hybrid composite exhibited attenuation behavior comparable, and in some regions slightly exceeding, that of the single-oxide systems, indicating that mixed fillers can effectively balance density and shielding efficiency. Oxide addition significantly reduced exposure and energy-absorption buildup factors below 1 MeV, with a moderate increase at higher energies associated with secondary radiation processes. Fast-neutron removal cross sections were also modestly enhanced, with Gd2O3-containing composites showing the highest values due to the combined effects of hydrogen moderation and neutron capture. The close agreement between Phy-X/PSD and Geant4 results confirms the reliability of the dual-method approach. Overall, HDPE composites containing about 60 wt.% oxide filler offer a practical compromise between shielding performance, manufacturability, and environmental safety, making them promising candidates for medical, nuclear, and aerospace radiation-protection applications.

This study aimed to design and characterize a compressible phantom that simulates adipose, glandular, and mixed breast tissues for mammography applications. Samples were prepared using paraffin gel wax, silicone oil, glass microspheres, and silicone. The linear attenuation coefficients and effective atomic numbers calculated at 15keV were 0.986cm-1 and 5.97 for adipose tissue, 1.381cm-1 and 7.81 for glandular tissue, and 1.772cm-1 and 6.91 for the mixed sample. Densities and Young's modulus values obtained from computed tomography and compression tests were 0.89g·cm-3 and 24.75kPa for adipose, 0.98g·cm-3 and 31.26kPa for glandular, and 0.95g·cm-3 and 26.27kPa for the mixed composition. Mammographic images were satisfactory, and the calculated mean glandular dose values closely matched those extracted from Digital Imaging and Communications in Medicine (DICOM) headers, with mixed and glandular samples showing similar values to patient data. Slight deviations from previously published results suggest potential areas for further refinement of phantom properties.

Self-attenuation in gamma-ray spectrometry: theory, correction methods, and applications.

A series of novel bis-piperazine derivatives (2a–2f) were synthesized and structurally characterized via Fourier transform-infrared and nuclear magnetic resonance spectroscopic techniques. Their gamma-ray shielding efficiencies were investigated through simulations on the Monte Carlo-based Geant4-GATE platform, and the results were benchmarked against data obtained from the XCOM and Phy-X software. A simulation model incorporating an NaI scintillation detector and a point gamma source was developed. Key shielding parameters, including mass attenuation coefficient, linear attenuation coefficient, half-value layer, and mean free path (MFP), were evaluated at gamma energies of 80, 120, 662, 1173, and 1332 keV. Additionally, the energy absorption buildup factor was calculated using EpiXS software, and penetration depths were assessed in the 0.015–15 MeV energy range for 10, 20, and 40 MFP values. Among the synthesized compounds, compound 2f (C35H54N6O2) had the highest gamma attenuation performance. The antimicrobial potential of compounds 2a–2f was evaluated in vitro against various microbial strains, including Gram-positive and Gram-negative bacteria as well as a fungal species. Furthermore, in silico molecular docking studies targeting DNA gyrase and GlcN-6-P synthase were performed for compounds 2d and 2f. Docking results indicated significant interactions, supporting their potential as antimicrobial agents. To assess the dynamic stability and binding persistence of the top-scoring complex (2VF5–2d), a 100 ns molecular dynamics simulation was conducted. The complex remained structurally stable throughout the trajectory, and binding free energy calculated via MM/PBSA (ΔGbind = −27.31 kcal/mol) further supported the strong and favorable interaction. These results highlight compound 2d as a promising candidate for further antibacterial development.

New fixable composite materials were developed based on silicone rubber reinforced with brine sludge as the main filler, and enhanced with bismuth oxide (Bi2O3) prepared from olive leaves as a natural and sustainable resource. For clarity, the samples are coded from SBB0 to SBB5, since (SBB) refers to Silicone Rubber + Brine Sludge + Bi2O3, starting with the reference sample (SBB0) without bismuth and going up to (SBB5) with the highest content (35% wt). The shielding properties of these composites were evaluated by measuring the attenuation coefficients such as Linear attenuation coefficient (LAC) and radiation shielding efficiency (RSE%) using photons from a wide range of energies, including low-energy X-rays (15–50 keV) as well as gamma rays (241Am at 59.5 keV, 133Ba at 81 and 356 keV, and 137Cs at 661.7 keV). The results showed that increasing the Bi2O3 content significantly improved the performance of the samples, with SBB4 and SBB5 achieving shielding efficiencies of nearly 100% against X-rays up to 50 keV and over 95% against low-energy gamma rays at only 1 cm thick. This study also showed that increasing the thickness to 5 cm increased the efficiency at high energies, with the SBB5 efficiency reaching approximately 57% at 661.7 keV, compared to less than 10% for the reference sample (SBB0) with a thickness of 1 cm. These results demonstrate that these new composites, made from recycled and environmentally friendly materials, are good and safe compounds for radiation shielding applications in the medical and industrial fields.

Study on radiation shielding of wheat flour mixed with barium sulfate (BaSO4) for replace lead. The moldable materials mixed with BaSO4 in composition 0%, 1%, 5%, 10%, 15% and 20% respectively. Radiation shielding characterization in diagnostic regions was conducted between 50-120 kVp, 100 mA, and 2 sec, with evaluations including the Linear Attenuation Coefficient (µ), Half Value Layer (HVL), Tenth Value Layer (TVL), and Mean Free Path (MFP). The results show that as BaSO4 content increases, the linear attenuation coefficient (µ) increases, while the HVL, TVL, and MFP decrease. When comparing HVL values at 120 kVp between the moldable materials in this study and standard radiation shielding materials such as commercial window glass, red brick, and concrete, it was found that the HVL values of the moldable materials with more than 1% BaSO4 were better. At a 20% BaSO4 concentration, the HVL values were nearly equivalent to those of X-ray windows, thyroid shields, and lead. Therefore, wheat flour moldable mixed with BaSO4 can be considered a viable alternative for radiation shielding.

Theoretically, composite materials designed by adding 3-6-9-12% by weight CoSO4 ceramic material into Al 2124 alloy were analyzed using the EpiXS program in the gamma transmittance range of 1 keV to 1x106 keV. The mean free path (MFP), half-value layer (HVL), and linear attenuation coefficient (LAC) parameters were analyzed using gamma radiation sources, including 241Am, 133Ba, 109Cd, 57Co, 60Co, 152Eu, and 137Cs. As a result of the analysis, it was determined that with the increase in CoSO4 by weight in Al 2124, the LAC values of the composite materials increased, while the HVL and MFP values decreased. In the photon energy range from 1 keV to 1x106 keV, the Al 2124 material had the highest HVL value with values ranging from approximately 1.49x10-4 cm to 7.72 cm, while it had the lowest LAC values with values ranging from approximately 4661.03 cm-1 to 0.09 cm-1. The highest LAC values were obtained by the Al 2124+ 12% CoSO4 composite material, which has the highest CoSO4 ratio by weight, with LAC values ranging from approximately 6417.7 cm-1 to 0.095 cm-1. Due to its best photon shielding performance, its HVL had values ranging from approximately 1.08x10-4 cm to 7.3 cm.

The safe containment of hazardous waste requires landfill liner materials with both effective radiation shielding and strong hydro-mechanical performance. This study investigates the potential of a bentonite-goethite mixture as a novel material for hazardous waste landfill liners. The study examines the radiation shielding of the mixtures, represented by the linear attenuation coefficient, through experimental (Na (Tl) spectrometer detector), numerical (MCNP code), and reference database (XCOM and PHY-X) approaches. Moreover, the hydraulic permeability and mechanical properties are evaluated experimentally. For this, the varying proportions of goethite from 10 to 50% were examined. The results show an increase of up to 20, 24, and 28 percent in the linear attenuation coefficient at gamma ray energies of Cs^{137} (661.6 keV) and Co^{60} (1173.2 and 1332.5 keV). Higher goethite percentages, correlating with density variations and enhancing radiation shielding effectiveness. Numerical and reference database results align closely with experimental findings, suggesting their utility for assessing other mixtures. The direct shear test reveals that with an increase of goethite proportion to 50 percent, the cohesion is reduced to half and the friction angle is inclined twice the pure bentonite values, attributed to bentonite reduction and goethite roughness. Unconfined compressive strength trends show 20% improvement at specific mixture composition with 30% goethite, while hydraulic conductivity inclines with goethite content to mathrm { 8.8times 10^{-10}} m/s. In this study the bentonite-goethite mixture illustrates improving radiation shielding and maintaining hydro-mechanical properties for landfill liners. This may offer a sustainable alternative using waste materials from mineral processing, contributing to waste management and environmental sustainability.

In recent years, polymer-based hybrid nanocomposites have emerged as promising alternatives to traditional heavy metal shields due to their low density, flexibility, and environmental safety. In this study, the synthesis of PS-PEG copolymers and the gamma radiation-shielding properties of PS-PEG/As2O3, PS-PEG/BN, and PS-PEG/As2O3/BN nanocomposites with different compositions are investigated. The goal is to find the optimal nanocomposite composition for gamma radiation shielding and dosimetry. Therefore, the mass attenuation coefficient (MAC), linear attenuation coefficient (LAC), half-value layer (HVL), tenth-value layer (TVL), effective atomic number, mean free path (MFP), radiation shielding efficiency (RPE), electron density, and specific gamma-ray constant were presented. Gamma rays emitted by the Eu source were detected by a high-purity germanium (HPGe) detector device. GammaVision was used to analyze the given data. Photon energy was in the vicinity of 121.8–1408.0 keV. The MAC values in XCOM simulation tools were used to compute. Gamma-shielding efficiency was increased by an increased number of NPs at a smaller photon energy. At 121.8 keV, the HVL of a composite with 70 wt% As2O3 NPs is 2.00 cm, which is comparable to the HVL of lead (0.56 cm) at the same energy level. Due to the increasing need for lightweight, flexible, and lead-free shielding materials, PS-b-PEG copolymer-based nanocomposites reinforced with arsenic oxide and BN NPs will be materials of significant interest for next-generation radiation protection applications.

This study utilized multiple materials to protect workers, particularly those in oil fields, from radiation hazards, including gamma rays. Each sample from the eight tantalum oxides: Mn2+Sn4+Ta2O8, Mn2+Ta2O6, Fe2+Ta2O6, Fe2+Ta2O6, (Y,U,Fe2+)(Ta,Nb)(O.OH)4, Bi(Ta,Nb)O4, (Ca,Na)2(Ta,Nb)2O6F, and Al4Ta3O13(OH) were evaluated as shields from the harm of gamma rays. All these materials are natural and insoluble in water. Here, the potential of using tantalum oxides mainly depends on the chemical composition of each material and its density, as well as their effectiveness in mitigating ionizing radiation. The calculated gamma ray shielding parameters include the linear attenuation coefficient, mass attenuation coefficient, half value layer, tenth value layer, mean free path, effective electron density, effective conductivity, and atomic cross-section. Electronic cross section, effective atomic number, and equivalent atomic number. These parameters were obtained by applying free Phy-X software within the photon interaction range of 0.015-15 MeV. The linear attenuation coefficient and mass attenuation coefficient decreased as the energy increased, whereas the other shielding parameters decreased as the energy decreased. Among all the tested samples, bismutotantalite Bi(Ta,Nb)O4 proved as the most effective material for gamma-ray shielding because of its heavy element content, high mean atomic number, and highest density, which are the key factors at intermediate energies (Compton effect). In contrast, materials such as {(Ca,Na)2(Ta,Nb)2O6F, Al4Ta3O13(OH), (Y,U,Fe2+)(Ta,Nb)(O. OH)4}, which contain lighter elements were less effective in protection from this radiation. At high photon energies, pair production occurs; consequently, these lighter materials do not strongly absorb radiation.

Six nickel alloys (Ni3Al, NiAl, Ni90Cr10, Ni80Cr20, Ni35Cr20Fe45, and Ni60Cr16Fe34) varied in their chemical formulas, mole fractions (%) of each element, density, and Mean Atomic Number ( , alongside other chemical-physical properties were subjected to a prediction study depending on using NGCal and Phy-X software. Both free and friendly attenuation prediction software were chosen to calculate the attenuation factors against Neutron, Gamma radiation, and X-rays exposure. The calculated factors included Linear Attenuation Coefficient (LAC), Mass Attenuation Coefficient (MAC), Half and Tenth Value Layer (HVL and TVL), and Mean Free Path (MFP) by both Phy-X and online NGCAL software. NGCAL software was utilized to study the effect of photons at (0.1, 1, 15) MeV and neutrons [fast at 4 MeV and thermal at 25.4 meV). By using Phy-X software, energy range was (0.015-15) MeV, characteristic X-rays (Kα, Kβ) included 29Cu, 37Rb, 42Mo, 47Ag, 56Ba, and 65Tb and radioactive isotopes were Am-241, Ba-133, Cd-109, Cs-137, Co-60, Eu-152, Fe-55, Na-22, and I-131. Additionally, protection efficiency (%) of each nickel alloy was calculated based on Lambert – Beer law by applying different thicknesses. The main aim of this prediction study is to provide workers that deal with Neutron, Gamma radiation, and X-rays particularly in the research, medical, industrial, and petroleum sectors most effective nickel alloy as a safe shielding material especially at high exposure energies. Both mathematical models indicated that Chromel (Ni90Cr10) as the highest density and high Nickel mole fraction exhibited the highest protection efficiency.

To address the limitations of traditional lead shielding (toxicity, weight) and unmodified bismuth fillers (poor dispersion), this study develops an improved "one-pot" ball milling method. This one-pot strategy effectively achieves in-situ silane (vinyltrimethoxysilane, A171) modification and transforms bismuth powder into a flake-like morphology. Here, A171 bonds covalently to the bismuth surface via Si─O─Bi linkages, thereby converting bismuth from hydrophilic to hydrophobic. This dual functionalization enables uniform dispersion of Bi in polydimethylsiloxane (PDMS) at a high filler loading of 70 wt% while retaining excellent mechanical flexibility (tensile strength 0.42 MPa, elongation 166%), thermal stability (30°C higher than that of pure PDMS), and fatigue resistance. The flake-like modified Bi (M-Bi) forms a 3D shielding network that extends X-ray propagation paths. The resulting 0.2 cm-thick 70M-Bi@PDMS composite exhibits 92% X-ray shielding efficiency for 60 keV X-rays, with corresponding linear (μ) and mass (µm) attenuation coefficients of 13.30 cm-1 and 3.50 cm2g-1, respectively, and 75% shielding efficiency at 80 keV. In terms of radiation shielding performance, it outperforms commercial lead shielding materials. This work provides a potentially scalable method for developing lead-free, lightweight, and flexible X-ray shielding materials for wearable applications.

Determination of self-absorption correction in the activity measurement of 210Pb.

In order to develop efficient substitutes for dangerous lead-based X-ray shielding materials, bismuth oxide (Bi2O3), copper cobaltite oxide (CuCo2O4), and zinc tungsten (ZnWO4) were added separately to polyvinyl chloride/polyethylene glycol (PVC/PEG) polymer composite. It is worth mentioning that this report is almost the first one dealing with such designed composites with the used elements and concentrations. Various shielding factors, including the linear and mass attenuation coefficients (LAC and MAC), mean free path (MFP), half and tenth value layers (HVL and TVL), effective atomic number (Z eff), effective density (N eff), equivalent atomic number (Z eq), exposure buildup factor (EBF) and energy absorption buildup factor (EABF) were computed. These calculations were done in the X-rays incident energy range between 0.01 and 10 MeV, for the PVC/PEG (S1), PVC/PEG/Bi2O3 (S2), PVC/PEG/CuCo2O4 (S3), and PVC/PEG/ZnWO4 (S4) composites. Comparing the S2 composite to the others; it is found that it has the greater X-ray shielding capabilities. Consequently, this composition could be a viable choice for protecting against X-ray risks.