Comparative studies on shielding properties of some steel alloys using Geant4, MCNP, WinXCOM and experimental results

Shielding performance of multi-metal nanoparticle composites for diagnostic radiology: an MCNPX and Geant4 study

Lead-free polymer composite shields are used in diagnostic radiology to protect patients from unnecessary radiation exposure. This study aimed to examine and introduce the radiation-shielding properties of single- and multi-metal nanoparticle (NP)-based composites containing Bi, W, and Sn using Geant4, MCNPX, and XCom for radiological applications. The mass attenuation coefficients and effective atomic numbers of single- and multi-metal NP-loaded polymer composites were calculated using the Geant4 and MCNPX simulation codes for X-ray energies of 20-140 keV. The nano-sized fillers inside the polydimethylsiloxane (PDMS:C₂H₆SiO) matrix included W (K = 69.5 keV), Bi (K = 90.5 keV), and Sn (K = 29.20 keV). For single-metal shields, one filler was used, while in multi-metal shields, two fillers were required. The MCNPX and Geant4 simulation results were compared with the XCom results. The multi-metal NP composites exhibited higher attenuation over a larger energy range owing to their attenuation windows. In addition, Bi₂O₃ + WO₃ NPs showed a 39% higher attenuation at 100-140 keV, and that of Bi₂O₃ + SnO₂ NPs was higher at 40-60 keV. Meanwhile, the WO₃ + SnO₂ NPs exhibited lower attenuation. The difference between the results obtained using Geant4 and XCom was less than 2%, because these codes have similar simulation structures. The results show that the shielding performance of the Bi₂O₃ + WO₃ filler is better than that of the other single- and multi-metal fillers. In addition, it was found that the Geant4 code was more accurate for simulating radiation composites.

Radiation shielding and dosimetric parameters of mexican artisanal bricks

In this work, were determined some radiation shielding and dosimetric parameters of three types of bricks for photons energy from 1 keV to 100 GeV photons using the Phy-X/PSD software, and for comparison also has been calculated the same parameters for NBS concrete. The parameters calculated are the linear attenuation coefficients (LAC), effective atomic numbers (Zeff), half value layers (HVL), the energy absorption buildup factors (EABF) and the exposure buildup factors (EBF), as well as the coefficients to use the geometric progression (G-P) fitting method. Obtained results show that the three types of bricks can be used safely for the design of medical facilities housing mammography units (less than 30 keV).

Evaluation of the Radiation Shielding Properties of a Tellurite Glass System Modified with Sodium Oxide

In this study, the X-ray and gamma attenuation characteristics and optical properties of a synthesized tellurite–phosphate–sodium oxide glass system with a composition of (85 − x)TeO₂–10P₂O₅–xNa₂O mol% (where x = 15, 20, and 25) were evaluated. The glass systems we re fabricated by our research group using quenching melt fabrication. The shielding parameters of as-synthesized systems, such as the mass attenuation coefficient (MAC), linear attenuation coefficient (LAC), effective atomic number (Z_eff), half-value layer (HVL), tenth value layer (TVL), mean free path (MFP), and effective electron density (N_eff) in a wide energy range between 15 keV and 15 MeV, were estimated using well-known PHY-X/PSD software and recently developed MIKE software. Herein, the optical parameters of prepared glasses, such as molar volume (V_M), oxygen molar volume (V_O), oxygen packing density (OPD), molar polarizability (αm), molar refractivity (R_m), reflection loss (R_L), and metallization (M), were estimated using MIKE software. Furthermore, the shielding performance of the prepared glasses was compared with that of commonly used standard glass shielding materials. The results show that the incorporation of sodium oxide into the matrix TeO₂/P₂O₅ with an optimum concentration can yield a glass system with good shielding performance as well as good optical and physical properties, especially at low photon energy.

Evaluation of Gamma Radiation Properties of Four Types of Surgical Stainless Steel in the Energy Range of 17.50-25.29 keV

In this study, the gamma radiation properties of four types of surgical-grade stainless steel (304, 304L, 316 and 316L) were investigated. The effective atomic number Zeff, effective electron density Neff and half-value layer (HVL) of four types of surgical-grade stainless steel were determined via the mass attenuation coefficient (μ/ρ). The μ/ρ coefficients were determined experimentally using an X-ray fluorescence (XRF) technique and theoretically via the WinXCOM program. The Kα1 of XRF photons in the energy range between 17.50 and 25.29 keV was used from pure metal plates of molybdenum (Mo), palladium (Pd), silver (Ag) and tin (Sn). A comparison between the experimental and theoretical values of μ/ρ revealed that the experimental values were lower than the theoretical calculations. The relative differences between the theoretical and experimental values were found to decrease with increasing photon energy. The lowest percentage difference between the experimental and theoretical values of μ/ρ was between -6.17% and -9.76% and was obtained at a photon energy of 25.29 keV. Sample 316L showed the highest value of μ/ρ at the energies 21.20, 22.19 and 25.29 keV. In addition, the measured results of Zeff and Neff for all samples behaved similarly in the given energy range and were found to be in good agreement with the calculations. The equivalent atomic number (Zeff) of the investigated stainless-steel samples was calculated using the interpolation method to compare the samples at the same source energy. The 316L stainless steel had higher values of μ/ρ, Zeff and Zeq and lower values of HVL compared with the other samples. Therefore, it is concluded that the 316L sample is more effective in absorbing gamma radiation.

Determination of radioprotective and genotoxic properties of sulfamide derivatives

Some potential drug active substances with the ability to reduce the effects of radiation on human tissues and cells were investigated. For this purpose, eight different types of sulfamide derivatives were synthesized and nuclear radiation protection parameters were determined. Neutron radiation reduction parameters such as the half-value layer effective removal cross-sections, mean free path, and the number of particles passing through the sample were determined with GEANT4 code. Additionally, the gamma radiation attenuation parameters of the materials examined were determined using Phy-X/PSD software in the energy area of 0.015–15 MeV. These parameters are the half-value layer, mass attenuation coefficient, mean free path, exposure buildup factor and effective atomic number. Neutron radiation absorption experiments were applied using an 241Am-Be fast neutron source. All results obtained for neutron radiation were compared with paraffin and water. It has been found that the ability of sulfamide derivatives to absorb these radiations is superior to reference materials. To determine whether these derivatives could have adverse effects on human health, their genotoxic potential was determined using the Ames/Salmonella bacterial reversion test. The results showed that these derivatives can be considered genotoxically safe in tests at concentrations up to 5 mM. Thus, it is suggested that the derivative materials examined in this study can be used as active substances for a drug to be made for protection against both neutron and gamma radiation.

The Influence of Titanium Dioxide on Silicate-Based Glasses: An Evaluation of the Mechanical and Radiation Shielding Properties

The mechanical and radiation shielding features were reported for a quaternary Na₂O-CaO-SiO₂-TiO₂ glass system used in radiation protection. The fundamentals of the Makishima-Mazinize model were applied to evaluate the elastic moduli of the glass samples. The elastic moduli, dissociation energy, and packing density increased as TiO₂ increased. The glasses' dissociation energy increased from 62.82 to 65.33 kJ/cm³, while the packing factor slightly increased between 12.97 and 13.00 as the TiO₂ content increased. The MCNP-5 code was used to evaluate the gamma-ray shielding properties. The best linear attenuation coefficient was achieved for glass samples with a TiO₂ content of 9 mol%: the coefficient decreased from 5.20 to 0.14 cm^-1 as the photon energy increased from 0.015 to 15 MeV.

Gamma Ray Shielding Properties of Yb3+-Doped Calcium Borotellurite Glasses

This research work aims to investigate the radiation shielding ability of a Yb3+-doped calcium borotellurite glass system. The system has the basic composition of CaF2–CaO–B2O3–TeO2–Yb2O3 but is denoted as TeBYbn for simplicity. The effect of increasing the TeO2 content in the glasses from 10 to 54 mol% was investigated, with five different chosen compositions and densities. The Phy-X/PSD program was used to investigate the mass attenuation coefficient (µ/ρ) of the samples. The mass attenuation coefficients were theoretically determined by using an online software for the calculation of shielding parameters. Other parameters were then calculated and analyzed, such as the linear attenuation coefficient (µ), transmission factor (TF), radiation protection efficiency (RPE), effective atomic number (Zeff), and mean free path (MFP). TeBYb5, the glass with the greatest TeO2 content, was shown to have the greatest µ/ρ; however, at greater energies, the differences between the values are practically negligible. µ was shown to increase with density, such as from 0.386 cm−1 to 0.687 cm−1 for TeBYb1 and TeBYb5 at 0.284 MeV, respectively. The least TF was found for samples with a thickness of 1.5 cm, proving an inverse correlation between the thickness of the sample and the TF. The HVL and TVL of the glasses decreased as the density of the samples increased, which means that TeBYb1 is the least effective out of the investigated glasses. The five samples proved to have a lower MFP than some other shielding glasses, demonstrating their capabilities as radiation shields. Based on the calculated parameters, TeBYb5 indicated the greatest photon attenuation ability.

Investigation of gamma-ray attenuation coefficients for solid boronized 304L stainless steel

In this study, mass attenuation coefficient (μ/ρ) and half value layer (HVL) at Eu-152 and Co-60 energies were used in measuring attenuation coefficients of the solid boronized AISI 304L stainless steel at 950 °C for 2, 4, 6 and 8 h. The experimental mass attenuation coefficients, μ/ρ, and HVL for these materials were compared to theoretical values obtained with WinXCOM. At the same time a new boriding agent (Baybora®-1) also developed for solid boriding method was used. The effects of boron layer size on radiation attenuation of boronized composites were evaluated in relation with gamma-ray transmission and the results of the experiments were interpreted. It could be understood that increased of boron layer in AISI 304L causes of increases in the attenuation coefficient values. The measured values agree with the theoretical values. The interaction parameters for selected samples have been computed and provided in the extended energy range 10^-3-10⁴ MeV. The shielding properties prepared stainless steel have also been compared with standard concretes as well as with the standard shielding stainless steel. It is found that the prepared stainless steel is the better shielding substitute to the conventional concretes as well as other standard shielding stainless steel. So, submicron size boron layer used composite materials are more convenient than micron size boron used composite materials as radiation shielding materials for nuclear applications.

Development of SiO2 based doped with LiF, Cr2O3, CoO4 and B2O3 glasses for gamma and fast neutron shielding

In this study, the fast neutron and gamma-ray absorption capacities of the new glasses have been investigated, which are obtained by doping CoO,CdWO4,Bi2O3, Cr2O3, ZnO, LiF,B2O3 and PbO compounds to SiO2 based glasses. GEANT4 and FLUKA Monte Carlo simulation codes have been used in the planning of the samples. The glasses were produced using a well-known melt-quenching technique. The effective neutron removal cross-sections, mean free paths, half-value layer, and transmission numbers of the fabricated glasses have been calculated through both GEANT4 and FLUKA Monte Carlo simulation codes. Experimental neutron absorbed dose measurements have been carried out. It was found that GS4 glass has the best neutron protection capacity among the produced glasses. In addition to neutron shielding properties, the gamma-ray attenuation capacities, were calculated using newly developed Phy-X/PSD software. The gamma-ray shielding properties of GS1 and GS2 are found to be equivalent to Pb-based glass.

Investigation and Characterization of Gamma Radiation Shielding Capacity of Heavy Minerals-Based Composite Materials

Radiation shielding is an indispensable ingredient in the design of an integrated system to attenuate the effects of radiation during various operations such as space, aircraft, and nuclear plant. Discerning and exploiting the properties of composite materials compatible for radiation shielding in those applications are therefore primary obligation. In this study, we present here the results of control, ilmenite-, and garnet-based composites radiation shielding capabilities. The gamma radiation shielding competency of control, ilmenite-, and garnet-based composite materials has been examined by using linear attenuation coefficient, mass attenuation coefficient (MAC), tenth value layer (TVL), and half value layer (HVL). A comparison among those composite materials has been studied to find out the best one for radiation shielding material. Factors influencing the radiation shielding capabilities such as mechanical properties, thermal properties, density, surface morphology, and Fourier-transform infrared spectroscopy (FTIR) analysis have been studied in comparative investigations. In this work, we show that garnet-based composite material has viable radiation shielding performances as compared to the control and ilmenite-based composites. Garnet-based composite exhibits lower impact energy to withstand against gamma radiation as compared to the other tested shielding materials.

Shielding behavior of artisanal bricks against ionizing photons

In the work reported in this article, were determined the shielding capabilities of three artisanal bricks used massively in the construction industry in Mexico. The linear attenuation coefficients for photons between 1 keV and 100 GeV are reported; and the half-value layers for energies used in the medical field, show that the three typical artisanal bricks have good shielding capabilities for photons below 50 keV. We compared the effective atomic numbers of one of our bricks against two widely used materials in the construction industry, and our results suggest that the greater the effective atomic number, the less material attenuation capacity. A comparison of the half-value layer of one of our bricks against the half-value layers of two clay bricks with different percentages of fly ash particles published in the literature, suggests that in the region between 0.001 and 2.8 MeV, all the three bricks have practically the same attenuation capacity and that from 2.8 MeV to 100 GeV the clay bricks with different percentages of fly ash particles, need less material to show the same attenuation capacity than our artisanal bricks. Energy Dispersed X-Ray Fluorescence suggests that regardless of the number of constituent elements in a sample, a critical mass per atom is required to have a positive impact on density; and as a consequence, in the capacity of attenuation of the materials. Normalized half-value layers suggest on the other hand, that the uncooked bricks have better shielding capabilities than cooked.

Comparison between MCNP5, Geant4 and experimental data for gamma rays attenuation of PbO-BaO-B2O3 glasses

Monte Carlo simulations, MCNP5 and Geant4 codes were developed to investigate radiation shielding properties of xPbO-(50-x) BaO-50B2O3 (where 5 ≤ x ≤ 45 mol%) consider to be glass systems. The mass attenuation coefficients were evaluated for different PbO concentration in the glass samples for varies photon energies of 0.356, 0.662, 1.173 and 1.332 MeV. The obtained mass attenuation coefficient values used to calculate half-value layer, effective atomic number, and electron density. The simulation parameters were compared with experimental data. Results show that the simulation results of mass attenuation coefficients for all PbO concentrations were generally in good agreement with experimental results, however, mass attenuation coefficient values calculated using Geant4 were slightly lower than MCNP5 and experimental data on the low energy of 0.356 MeV. The results obtained from MCNP5 and Geant4 codes might be able to assessment mass attenuation for different glass systems. Furthermore, gamma ray, fast neutron and charged particle interaction for the glass systems were studied using buildup factors, fast neutron removal cross sections and ranges respectively.

Gamma and X-Ray Shielding Properties of Various Types of Steels

We have calculated the gamma and X-ray shielding parameters such as mass attenuation coefficient, half value layer (HVL), tenth value layer (TVL), specific gamma ray constant, effective atomic number, and buildup factors in various steels. By studying these X-ray and gamma interaction parameters, we have selected the best steel which can be used for the X-ray and gamma shielding material. The steel type 20Mo-4 is having higher values of mass attenuation coefficient, specific gamma ray constant, effective atomic number, and buildup factor and smaller values of HVL and TVL. A detail analysis of X-ray/gamma interaction in the different steels reveals that the steel type (S15) 20Mo-4 is good absorption of both X-ray/gamma radiations.

A novel comprehensive utilization of vanadium slag: As gamma ray shielding material

New exploration of vanadium slag as gamma ray shielding material was proposed, the shielding properties of vanadium slag was higher than concrete when the energy of photons was in 0.0001MeV-100000MeV. Vanadium slag/epoxy resin composites were prepared, shielding and material properties of materials were tested by (60)Co gamma ray, simultaneous DSC-TGA, electronic universal testing machine and scanning electron microscopy, respectively. The results showed that the shielding properties of composite would be better with the increase of vanadium slag addition amount. The HVL (half value layer thickness) of vanadium slag was between Lead and concrete while composite was higher than concrete when the addition amount of vanadium slag was 900 used as material to shield (60)Co gamma ray, also the resistance temperature of composite was about 215°C and the bending strength was over 10MPa. The composites could be used as injecting mortar for cracks developed in biological concrete shields, coating for the floor of the nuclear facilities, and shielding materials by itself.