Py-MLBUF: Development of an online-platform for gamma-ray shielding calculations and investigations

Investigation of natural radionuclides and radiation shielding potential of some commonly used building materials in Northwestern Nigeria

This study assessed the gamma-ray shielding potential of clay, sand, gypsum and kaolin commonly used as a building material in Northwestern, Nigeria. The radiological status of the samples was first evaluated by determining the activity concentrations of 238U, 232Th and 40K using NaI (Tl) detector after which elemental composition and mass density were determined using Neutron Activation Analytical Technique. After which the mass attenuation coefficients (MAC), linear attenuation coefficients (LAC), half value layer (HVL), tenth value layer (TVL), and effective atomic number (Zeff) were determined experimentally and theoretically using standard point sources of 137Cs and 60Co photon peaks (0.662 and 1.332, 1.173) MeV and Py-MLBUF software. The activity concentrations were found to range from 51 to 59 Bq kg-1 with a mean value of 59 Bq kg-1 for 238U, 24 to 27 Bq kg-1 with a mean value of 29 Bq kg-1 for 232Th, and 219 to 247 Bq kg-1 with a mean value of 247 Bq kg-1 for 40K which were about within the world recommended values of 33, 45 and 420 Bq kg-1 respectively. The results of the elemental compositions show that Si, Al, K, Fe, and Ba in clay and sand samples have concentrations in the range of 36.83-78.48%, 1.92-26.05%, 6.33-21.96%, 2.39-19.09%, and 0.09-1.44%, respectively, while in kaolin and gypsum, results revealed that Si, Al, K, Fe, and Ca range between 0.34 and 65.52%, 1.14-35.82%, 0.00-12.12%, 0.00-5.77%, and 0.00-96.6%, respectively. However, the concentrations of other elements such as Mg, Ti, Mn, Zn, Na, and Ba varied significantly with the samples. The results showed that clay has an average density of 1.96 g/cm3, sand has 2.32 g/cm3, kaolin has 2.63 g/cm3, and gypsum has the highest density with a value of 2.66 g/cm3 compared to other samples. During the measurements, a thallium-activated sodium-iodide NaI (TI) detector was used. A narrow beam transmission geometry condition was adopted for the measurements to ensure minimal scattered radiation. Absorption and attenuation of gamma beams as a function of sample thickness against gamma energy generally exhibit an increasing gamma ray behaviour as the sample thickness increases from 1 to 3 cm. The results showed that the gypsum, kaolin, sand, and clay were capable of attenuating 63.5%, 61.5%, 58.4%, and 44.2 of gamma-ray photons of energy 0.662 MeV at 3 cm thickness %, respectively, and 40.6%, 32.9%, 30.6%, and 27.3% of gamma energy 1.332 MeV at 3 cm thickness, respectively. The results showed that MAC, LAC, and Zeff of all the samples decreased with an increase in photon energy, while those of HVL and TVL increased. The experimental results for all the gamma-ray shielding parameters were found to be in good agreement with the theoretical values obtained using Py-MLBUF. The results have shown that all the samples have similar photon attenuation behaviours; however, gypsum has the best shielding potential than kaolin and this is attributed due to its highest density value.

Translocation of tungsten(vi) oxide/gadolinium(iii) fluoride in tellurite glasses towards improvement of gamma-ray attenuation features in high-density glass shields

This study investigates the effect of substituting tungsten(vi) oxide/gadolinium(iii) fluoride in tellurite glasses whose densities varies from 5.0879 to 5.3246 g/cm3 on gamma-ray absorption properties. A range of fundamental absorption parameters, including attenuation coefficients, half-value layer thicknesses, effective atom and electron numbers, effective conductivity, exposure, and energy absorption buildup factors, were studied for five different glass samples with varying substitution ratios. The ratio of tungsten(vi) oxide to gadolinium(iii) fluoride varied between 0 and 20 mol%, as well as the TeO2 ratio in the composition was maintained between 90 and 80 mol%. The sample with the composition of 80–20 mol% TeO2/WO3, which attained the maximum density value with 20 mol% WO3 addition, showed the highest gamma-absorption capabilities based on the obtained findings in the range of 0.015–15 MeV. In consideration of the mechanical and physical properties of WO3 in tellurite glasses, it can be concluded that WO3 incorporation is a crucial monotonic process that may be utilized to further improve the properties of glass shields.

Mechanical properties, elastic moduli, and gamma ray attenuation competencies of some TeO2–WO3–GdF3 glasses: Tailoring WO3–GdF3 substitution toward optimum behavioral state range

We report the mechanical properties, elastic moduli, and gamma ray attenuation properties of some TeO2–WO3–GdF3 glasses. Using the chemical composition of the selected glasses, the dissociation energy per unit volume (G t ) and the packing density (V t ) were calculated. Using the G t and V t values, Young’s, Shear, Bulk, Longitudinal Modulus, and Poisson’s ratio of the glasses are calculated. Next several fundamental gamma ray attenuation properties such as linear and mass attenuation coefficients, half value layer, mean free path, effective atomic number, effective electron density, effective conductivity, exposure, and energy absorption buildup factors are calculated in 0.015–15 MeV energy range. As a consequence of WO3–GdF3 substitution, the glass densities are observed in different values. The overall gamma ray attenuation properties are found to be enhanced through WO3 addition. Moreover, the increasing WO3 incorporation into glass configuration decreases the overall elastic moduli of glasses. It can be concluded that increasing WO3 may be a useful tool for enhancing the gamma ray attenuation qualities and decreasing the elastic moduli of TeO2–WO3–GdF3 in situations where a material with versatile mechanical properties is required.

A Promising Glass Type in Electronic and Laser Applications: Elastic Moduli, Mechanical, and Photon Transmission Properties of WO3 Reinforced Ternary-Tellurite Glasses

We report the symmetry of mechanical and gamma-ray attenuation properties for some tellurite glasses through elastic moduli, mechanical, and transmission properties as a function of varied WO3 amount in glass configuration. Four glass samples, along with different molar compositions as well as WO3/GdF3 substitution ratios, are investigated. Transmission properties using several essential parameters, such as attenuation coefficients, half-value layers, effective atomic numbers, effective conductivity, and buildup factors, are calculated in the 0.015–15 MeV energy range. Moreover, elastic moduli and Poisson’s ratios (σ) of the studied glass are calculated using the Makishima–Mackenzie model. The M4 sample with the highest WO3 addition is found with superior photon attenuation properties among the glasses investigated. Poisson’s ratio (σ) is increased, while all elastic moduli are decreased. Young’s modulus is reported as 62.23 GPa and 36.45.37 GPa at the highest and lowest WO3 mol%, respectively. It can be concluded that WO3 is a functional and monotonic tool in ternary-tellurite glasses for multiple modifications and enhancement purposes on gamma-ray attenuation, elastic moduli, and mechanical properties. It can also be concluded that increasing the WO3 amount in tellurite glasses may be considered a tool in terms of providing symmetry for mechanical and gamma-ray attenuation properties.

Investigation of the nuclear radiation interaction parameters of selected polymers for radiation therapy and dosimetry

The mass attenuation coefficient (MAC), effective atomic number (Z_eff), equivalent atomic number (Z_eq), fast neutron removal cross-section (FNRCS), energy absorption buildup factor (EABF), mass-energy absorption coefficient (MenAC), relative kerma, and computed tomography (CT) numbers were calculated for the alginates, bisphenol A-glycidyl methacrylate (Bis-GMA), chitin, hyaluronic acid, polycaprolactone (PCL), polyether ether ketone (PEEK), polyethylene glycol (PEG), polyglycolide (PGA), polylactic acid (PLA), poly lacto-co-glycolic acid (PLGA), poly methyl methacrylate (PMMA), poly vinyl alcohol (PVA), polyvinylpyrrolidone (PVP), triethylene glycol dimethacrylate (TEGDMA), and urethane dimethacrylate (UDMA) polymers using the Phy-X/PSD and Py-MLBUF software. The total stopping power (TSP) of electrons, protons, and alpha particles was calculated for the selected polymers using the ESTAR, PSTAR, and ASTAR programs. The effective atomic number for absorption and charged particle (electron, proton, alpha, and carbon ion) interactions were estimated for the selected polymers using Phy-X/ZeXTRa software. The FNRCS values of Bis-GMA, PCL, PEG, PMMA, and PVP were similar to those of the human tissues. For the selected polymers, the Z_eff values for electron, proton, alpha, and carbon ion interactions of PCL, PEG, PLGA, and PVA were similar to those of human tissues, except for the cortical bone, across the entire energy range. These results are expected to assist in selecting suitable polymers as tissue-equivalent materials in the desired energy range for photon, neutron, and charged-particle interactions. This study is expected to be useful for radiation therapy and dosimetry.

Gamma, neutron, and heavy charged ion shielding properties of Er3+-doped and Sm3+-doped zinc borate glasses

This study aimed to investigate the nuclear radiation shielding properties of erbium (Er)-reinforced and samarium (Sm)-reinforced borate glasses. In the 0.015–15 MeV photon energy range, attenuation coefficients, as well as half-value layer tenth-value layers, and the mean-free path have been calculated. Additionally, effective, and equivalent atomic numbers, effective atomic weight, electron density, and exposure and energy absorption build-up factors were also calculated. To evaluate the overall nuclear radiation attenuation competencies of Er-rich and Sm-rich glasses, effective removal cross-section values for fast neutrons and projected range/mass stopping power values for alpha and proton particles were also determined. The glass sample BZBEr2.0 had the highest linear and mass attenuation coefficients (µ and µ m), effective conductivity (C eff), the effective number of electrons (N eff), and effective atomic number (Z eff) values as well as the lowest half-value layer (T 1/2), tenth value layers (T 1/10), mean free path (λ), exposure build-up factor, and energy absorption build-up factor values. µ m values were reported as 2.337, 2.556, 2.770, 2.976, 2.108, 2.266, 2.421, 2.569, and 2.714 for BZBEr0.5, BZBEr1.0, BZBEr1.5, BZBEr2.0, BZBSm0.0, BZBSm0.5, BZBSm1.0, BZBSm1.5, and BZBSm2.0 glass samples at 0.06 MeV, respectively. The results showed that Er has a greater effect than Sm regarding the gamma-ray shielding properties of borate glasses. The results of this investigation could be used in further investigations and added to older investigations with the same aim, to aid the scientific community in determining the most appropriate rare-earth additive, to provide adequate shielding properties based on the requirement.

Simulation of Gamma-Ray Transmission Buildup Factors for Stratified Spherical Layers

Deterministic particle transport codes usually take into account scattered photons with correct attenuation laws and application of buildup factor to incident beam. Transmission buildup factors for adipose, bone, muscle, and skin human tissues, as well as for various combinations of these media for point isotropic photon source with energies of .15, 1.5 and 15 MeV, for different thickness of layers, were carried out using Geant4 (version 10.5) simulation toolkit. Also, we performed the analysis of existing multilayered shield fitting models (Lin and Jiang, Kalos, Burke and Beck) of buildup factor and the proposition of a new model. We found that the model combining those of Burke and Beck, for low atomic number (Z) followed by high Z materials and Kalos 1 for high Z followed by low Z materials, accurately reproduces simulation results with approximated deviation of 3 ± 3%, 2 ± 2%, and 3 ± 2% for 2, 3, and 4 layers, respectively. Since buildup factors are the key parameter for point kernel calculations, a correct study can be of great interest to the large community of radiation physicists, in general, and to medical imaging and radiotreatment physicists, especially.

A Monte Carlo investigation of some important radiation parameters and tissue equivalency for photons below 1 keV in human tissues

The attenuation coefficients are important input values in estimating not only the dose and exposure in radiotherapy and medical imaging, but also in the proper design of photon shields. While studies are widely available above 1 keV, the attenuation coefficients of human tissues for photon energies less than 1 keV have not been studied yet. In this study, the attenuation coefficients of water and some human tissues were estimated for low energy photons using the MCNP6.1 code in the energy region 0.1 keV-1 keV. Mass attenuation coefficients were estimated at photon energies of 100, 150, 200, 250, 300, 350, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950 and 1000 eV for water and ten human tissues (Soft, Breast, Lung, Bone, Brain, Eye lens, Ovary, Skin, Thyroid and Prostate). Results were compared with those available in literature and a fairly good agreement has been obtained. These data were then used to calculate the mean free path, half value layer, tenth value layer, effective atomic number and specific gamma-ray constant (useful for calculation of dose rate) as well. Moreover, for comparison the effective atomic number of the water has been obtained using the results of this work and using the data available in NIST database from 0.1 to 1 keV. In addition, the human tissues were compared with some tissue equivalent materials in terms of effective atomic number and specific gamma-ray constant to study the tissue equivalency from the results, the muscle-equivalent liquid with sucrose has been found to be the best tissue equivalent material for soft tissue, eye lens and brain with relative difference below 4.1%.

Trivalent Ions and Their Impacts on Effective Conductivity at 300 K and Radio-Protective Behaviors of Bismo-Borate Glasses: A Comparative Investigation for Al, Y, Nd, Sm, Eu

We aimed to determine the contribution of various trivalent ions like Al and rare-earths (Y, Nd, Sm, Eu) on resistance behaviors of different types of bismo-borate glasses. Accordingly, eight different bismuth borate glasses from the system: 40Bi₂O₃–59B₂O₃–1Tv₂O₃ (where Tv = Al, Y, Nd, Sm, and Eu) and three glasses of (40Bi₂O₃–60B₂O₃; 37.5Bi₂O₃–62.5B₂O₃; and 38Bi₂O₃–60B₂O₃–2Al₂O₃) compositions were extensively investigated in terms of their nuclear attenuation shielding properties, along with effective conductivity and buildup factors. The Py-MLBUF online platform was also utilized for determination of some essential parameters. Next, attenuation coefficients, along with half and tenth value layers, have been determined in the 0.015 MeV–15 MeV photon energy range. Moreover, effective atomic numbers and effective atomic weight, along with exposure and energy absorption buildup factors, were determined in the same energy range. The result showed that the type of trivalent ion has a direct effect on behaviors of bismo-borate glasses against ionizing gamma-rays. As incident photon energy increases, the effective thermal conductivity decreases rapidly, especially in the low energy range, where photoelectric effects dominate the photon–matter interaction. Sample 8 had the minimum heat conductivity at low photon energies; our findings showed that Eu-reinforced bismo-borate glass composition, namely 40Bi₂O₃–59B₂O₃–1Eu₂O₃, with a glass density of 6.328 g/cm³ had superior gamma-ray attenuation properties. These outcomes would be useful for the scientific community to observe the most suitable additive rareearth type and related glass composition for providing the aforementioned shielding properties, in terms of needs and utilization requirements.

Newly Developed Vanadium-Based Glasses and Their Potential for Nuclear Radiation Shielding Aims: A Monte Carlo Study on Gamma Ray Attenuation Parameters

This study aimed to investigate different types of glasses based on the 46V₂O₅-46P₂O₅-(8-x) B₂O₃-xCuO system in terms of their nuclear radiation shielding properties. Accordingly, five different CuO-doped vanadate glasses were investigated extensively to determine the necessary gamma shielding parameters along with effective conductivity at 300,000 and buildup factors. Phy-x PSD software was used for determination of these vital parameters. Furthermore, these parameters, such as half value layer, tenth value layer, and mean free path were investigated in a broad energy range between 0.015 and 15 MeV. The results revealed that the amount of CuO reinforced in each sample plays an essential role in determination of the shielding abilities of the samples. The sample with the highest CuO content had the highest linear attenuation coefficient and mass attenuation coefficient values. Additionally, the lowest mean free path, half value layer, and tenth value layer values were recorded for glass sample VPCu8. There was an inverse relation between the effective conductivity and effective atomic number and photon energy; that is, as energy increases, the effective conductivity and effective atomic number decreased rapidly, especially in the regions of low energy. Glass sample VPCu8 reported the highest values for both parameters. Moreover, glass sample VPCu8 had the lowest exposure buildup factor and energy absorption buildup factor values. Our findings showed that CuO-reinforced vanadate glass composition, namely 46V₂O₅-46P₂O₅-8CuO, with a glass density of 2.9235 g/cm³, was reported to have superior gamma ray attenuation properties. These results would be helpful for scientists in determining the most appropriate additive rare earth type, as well as the most appropriate glass composition, to offer shielding characteristics similar to those described above, taking into consideration the criteria for usage and the needs of the community. The results of this research will be useful to the scientific community in evaluating the prospective characteristics of CuO-doped glass systems and related glass compositions. CuO-doped glass systems and associated glass compositions have a wide range of properties.

A Novel and High-Precision Method for Calculating the γ-Ray Build-Up Factor for Multilayer Shields

In the field of radiation protection, the point-kernel code method is a practical tool widely used in the calculation of 3-D radiation field, and the accuracy of the point-kernel integration method strongly depends on the accuracy of the build-up factor. It is well known that calculation of the build-up factor for single-layer shields is composed of single material, but it is very complicated to calculate the build-up factor for multilayer shields (MLBUF). Recently, a novel and high-precision method based on the deep neural network (DNN) for calculating MLBUF has been proposed. In this paper, the novel method is described completely by slab models. Through the study of photon transport in multilayer shields, the parameters that mainly affect the calculation of build-up factor are analyzed. These parameters are trained by DNN as the input vectors, and the build-up factor for multilayer shields is predicted based on the trained DNN. The results predicted by DNN confirm that the method can calculate the build-up factor for multilayer shields quickly and accurately. The method has been preliminarily applicated into a 3-D radiation field calculation software, and it has proved that the method for calculating MLBUF has a broad application prospects in 3-D radiation field calculation.