Gamma Radiation Shielding Research Articles

Synthesis, structural, optical, dielectric properties, gamma radiation attenuation, and antimicrobial activity of V-doped hydroxyapatite nanorods

The nanoscale hydroxyapatite (HAp) is a significant material applied for bone tissue engineering in the human body. This study focuses on the impact of vanadium addition on nano-sized HAp synthesized by sol-gel/hydrothermal technique and microwave device. The as-prepared nanocomposites were analyzed by X-ray diffraction (XRD), field emission-scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDX), Fourier-transformed infrared spectroscopy (FTIR), and Raman spectroscopy. The calculated crystallite size of the pure and V-HAp ranged from 15.73 nm to 20.77 nm, as supported by the XRD technique. The surface morphology of V-HAp samples is nanorods. Furthermore, the diffused reflectance helps to obtain the absorption spectra and the bandgap of the investigated samples. The dielectric constant and AC electrical conductivity are varied with the applied frequency and recorded at room temperature for HAp and different V-concentrations HAps. The gamma ray's absorption was also studied to consider the gamma attenuation of the tested samples using Cs-137 and Am-241 radioactive sources. The antimicrobial activity of the synthesized nanopowders was considered against pathogenic Gram-negative bacteria (P aeruginosa and Klebseilla sp), Gram-positive bacteria (Micrococcus sp and Bacillus subtilis), and yeast pathogen (Candida albicans). Therefore, vanadium-doped HAp nanostructured can be used as a multifunctional material vis microbial inhibitory and gamma radiation shielding materials.

A metal-ceramic-rubber composite for hybrid gamma and neutron radiation shielding

In this study, silicone rubber (polydimethylsiloxane) matrix was incorporated with bismuth (III) oxide and hexagonal boron nitride (hBN) functional fillers to develop a flexible composite material that can shield both neutron and X/gamma radiations. Bismuth, as having a high atomic element weight is a very effective material for X/gamma electromagnetic radiation shielding, while hBN has a very high neutron cross-section due to its boron and nitrogen contents. On the other hand, the matrix material that is high temperature vulcanized (HTV) silicone rubber has superior properties of good flexibility, high transparency, and mechanical properties. Hexagonal boron nitride has unique properties and has a similar structure with graphite that is used for neutron moderation. Mechanical test results showed that the elastic modulus of the optimum sample has improved 4 times compared to control sample. Thermal, X ray and neutron attenuation tests were carried out for the developed composite materials. The curing behaviour was investigated in detail using Moving Die Rheometer. Kinetic studies of the vulcanization process were carried out in a very detailed way and high regression values up to 0.98 has been achieved. Non-destructive radiography images were taken to investigate the particle distribution and radiation attenuation of the prepared composites. It was seen that the composite material developed has a considerable attenuation ratio for both neutron and X/gamma radiations. X-ray attenuation test results for silicone rubber containing 20% Bi2O3 and 20% hBN with thickness of 6.4 mm were shown that the intensity of the incoming rays attenuated by 84.1%. Metal-ceramic-rubber composite material with 6.6 mm thickness shielded 65.8% of incoming neutrons.

Mechanical and gamma radiation shielding properties of natural rubber composites: effects of bismuth oxide (Bi2O3) and lead oxide (PbO)

ABSTRACT This work aims to compare the performance between natural rubber (NR) composites with lead oxide (PbO) and bismuth oxide (Bi2O3) as shielding fillers for gamma radiation shielding applications. Modulus at 100% elongation, tensile strength, elongation at break, hardness and a specific gravity of the NR composites were investigated. The results indicated that NR/Bi2O3 and NR/PbO composites have no significant difference in terms of modulus and hardness values, while the NR/PbO composite exhibited better tensile strength and specific gravity than that of NR/Bi2O3 composite. However, NR/Bi2O3 composite exhibited better performance in oil resistance and thermal stability than the one with PbO. Gamma radiation shielding properties including mass attenuation coefficient (), effective atomic number (Zeff), effective electron density (Ne) and half-value layer (HVL) have also been studied. It is seen that both the composites exhibited better radiation shielding properties. Furthermore, the radiation properties were in good agreement with the calculated theoretical values. In addition, both the composites of NR with PbO and Bi2O3 particles showed excellent radiation shielding properties compared to neat NR as well as commercially available materials including window, ordinary concrete and haematite-serpentine. The material developed in the present investigation can be used as efficient flexible radiation shielding materials. However, lead (Pb) is not suitable to use as a radiation shielding material due to its toxic nature to the human and the environment. Therefore, NR with Bi2O3 is an appropriate choice for producing novel wearable radiation shielding materials to manufacture gloves, aprons, rubber underwear and other wearable materials.

Design, structure, microstructure and gamma radiation shielding properties of refractory concrete materials containing Ba- and Sr-doped cements

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–Al2O3, SrO–CaO–Al2O3–ZrO2, SrO–Al2O3 and BaO–CaO–Al2O3–ZrO2 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.

Bentonite based ceramic materials from a perspective of gamma-ray shielding: Preparation, characterization and performance evaluation

Exposure to gamma-rays is hazardous for humans and other living beings because of their high penetration through the materials. For this reason, shielding materials (usually lead, copper and stainless steel) are used to protect against gamma rays. This study’s objective was to prepare ceramic materials for gamma radiation shielding by using different natural bentonite clays. Gamma-ray attenuation performances of the prepared shielding materials at different thicknesses were investigated and evaluated for different gamma-ray energies from different standard point gamma radiation sources (251Am, 57Co, 137Cs, 60Co, and 88Y). The mass and linear attenuation coefficients of the prepared ceramics vary between 0.238 and 0.443 cm2 g−1 and between 0.479 and 1.06 cm−1, respectively, depending on their thicknesses. Results showed that these materials could be prioritized because of their evidential properties of gamma radiation protection in radiation applications.

Effect of F-Ba and Pb-Zn tailing on the mechanical and radiation shielding properties of cement mortars

The use of mine waste and tailing in concrete and mortar has widely expanded in the past years. Several studies aim to contribute to the recovery of these rejects and preserve natural raw materials, on the other hand, to improve the physio-mechanical performance of concrete. In the present investigation, the impacts of Pb-Zn and F-Ba as fine aggregate replacement in mortar were analyzed. The outcomes indicated that substitution materials affect the mechanical strength and gamma radiation shielding properties of the mortar. In this regard, the compressive strength of samples made with substitutions of 5%, 10% and 20% of F-Ba tailings were slightly decreased with those of the reference test. However, the replacements with Pb-Zn tailings cause a significant strength decrease of mortar samples (from 68% to 94%). On the contrary, the flexural strength was improved adding one of these types of tailing.Concerning the absorption properties for gamma radiation, obtained results show that incorporation of these solid residues increases the attenuation of gamma rays. The mortars made with F-Ba tailings are more effective than others. The influence of tailings is significant mainly between 0.122 and 0.622 MeV and the highest attenuation is observed for Sample 5′ and 6′. This could be explained by the relative content of heavy minerals in each waste. Furthermore, the half thickness decreases with the increase of mine tailings percentage. The difference is more marked at high energies up to 0.15 MeV. Subsequently, the obtained materials could be utilized for shielding against gamma radiation.

Influence of modifier oxide on the structural and radiation shielding features of Sm3+-doped calcium telluro-fluoroborate glass systems

A sequence of Sm3+-incorporated calcium telluro-fluoroborate glasses by changing the modifier oxide was prepared via the melt-quenching method. The physical, structural, and gamma radiation shielding properties are investigated. XRD spectra confirmed the glassy state. The glasses’ compactness was explored via the structural features like the boron-boron separation, oxygen molar volume, and oxygen packing density. Mechanical and optical properties such as Poisson’s ratio, optical electronegativity, optical basicity, two-photon absorption (TPA) coefficient, and ionic and covalent characters were evaluated and discussed per modifier concentration. The photon attenuation attributes of the glasses were computed by means of the MCNP-5 code. The mass attenuation coefficient (MAC) was simulated in the energy region of 0.015–15 MeV. The highest MAC achieved at gamma energy 0.015 MeV increased from 25.004 to 33.165 cm2g−1 with increasing the CaO ratios between 0 and 40 wt%. Besides, several attenuation factors, such as the mean free path and the radiation protection efficiency, were evaluated connected with the MAC’s simulated values. The study showed that the fabricated glasses’ radiation protection efficiency at 0.5 MeV increased from 33.39 to 39.31, increasing the CaO content from 0 to 40 mol%.

Wearable and flexible radiation shielding natural rubber composites: Effect of different radiation shielding fillers

Flexible shielding materials based on natural rubber (NR) composites were successfully prepared and developed. The different radiation shielding fillers including barium carbonate (BaCO3), bismuth oxides (Bi2O3) and barium sulfate (BaSO4) were used as X-rays and gamma rays radiation shielding fillers in NR composites. Crosslink density and mechanical properties (i.e., modulus at 100% elongation, tensile strength, % Elongation at break, hardness and specific gravity) were investigated extensively. It was found that NR/Bi2O3 composite gave highest crosslink density, tensile strength, % Elongation at break and specific gravity. It is noted that all types of radiation shielding fillers showed insignificantly difference in term of modulus at 100% elongation and hardness. For the resulting of gamma radiation attenuation properties, it is seen that NR/Bi2O3 composite gave highest mass attenuation coefficient (μm), lead equivalent and lowest half value layer (HVL), inferring that NR/Bi2O3 composite could be better gamma radiation attenuation than those of NR/BaCO3 and NR/BaSO4 composite. For the X-rays radiation attenuation properties in terms of liner attenuation coefficient (μ), half value layer (HVL) and lead equivalent, the results gave good agreement with gamma radiation attenuation properties. In comparison of half value layer between NR/radiation shielding fillers composites and commercial available radiation shielding materials showed that the NR/Bi2O3 composite provided better gamma radiation shielding than those of commercial radiation shielding window, serpentine, hematite serpentine and ordinary concrete. In addition, all NR composite with different shielding fillers exhibited greater X-rays radiation shielding than those of commercial and X-rays window with better performance in term of flexibilities, extensibilities and elasticities. NR/Bi2O3 composite is the most suitable choice of preparing a novel flexible radiation shielding materials.

Improvement of Gamma Radiation Shielding Features for Fluorophosphate Glasses Doping with Sm2O3 (PZBKNA)

This research reported on the radiation safety characteristics of doped fluorophosphate glasses with heavy rare earth lanthanide (Sm2O3) in the composition 40P2O5/30ZnO/20BaF2/3.8K2TeO3/1.2Al2O3/5.0Nb2O5/30000 ppm Sm2O3 and 40P2O5/30ZnO/20BaF2/3.8K2TeO3/1.2Al2O3/5.0Nb2O5/40000 ppm Sm2O3 in mol%. The parameters for shielding like that mass attenuation coefficient, MAC, linear attenuation coefficient, LAC, tenth value layers, TVL, half-value layers, HVL, effective atomic number, (Zeff), mean free path, MFP, electron density, Neff, electronic cross-sections, ECS, and total atomic cross-sections, ACS, were calculated between 0.015 and 15 MB of preparation glasses. The protection parameters of the current glasses are good in comparison to industrial materials used for nuclear shieldings, such as glass RS 253, ordinary concrete (OC), hematite serpenite (HS), or basalt magnet (BM). From the above mention results, the prepared glasses can be used as radiation safety materials.

Bismuth modified gamma radiation shielding properties of titanium vanadium sodium tellurite glasses as a potent transparent radiation-resistant glass applications

This work reported the radiation shielding characteristic of the bismuth titanium vanadium sodium tellurite glass system. The density of the specially-developed glass samples was increased from 2.21 to 4.01 g/cm3 with the addition of Bi2O3, despite the fact the molar volume is decease within 85.43–54.79 cm3/mol. The WinXcom program was used to approximate the effect of Bi2O3 on the gamma radiation shielding parameters of bismuth titanium vanadium sodium tellurite glasses. The μm values decrease with the increase of Bi2O3 concentration. The computed data shows that the glass sample with 20 mol.% of Bi2O3 content has the greatest radiation attenuation performance in comparison to other selected glasses. The Bi2O3–TiO2–V2O5–Na2O–TeO2 glass system shows excellent neutron shielding material with high long-term light transmittance and discharge resistance and could be potentially used as transparent radiation-resistant shielding glass applications.

Ta2O5-doped zinc-borate glasses: physical, structural, optical, thermal, and radiation shielding properties

In this study, examination of the physical, structural, optical and thermal properties of the glasses with the glass composition (100 − x)(0.6ZnO·0.4B2O3)·xTa2O5 (0, 1, 2, 3, 4 mol%) was aimed. Physical properties of the glasses synthesized with the classical melt-quenching method were calculated; density and molar volume values of the synthesized glasses based on the doping quantity were calculated. FTIR spectra were used in order to determine the structural properties in doped glasses. During the optical examinations of the synthesized glasses, direct and indirect optical band gap values were obtained with the help of Tauc plot method, and Urbach energies were calculated. Glass transition temperatures, melting temperatures, crystallization temperatures, and thermal stabilities were determined with DSC analysis. The main purpose of this study is to synthesize high-density glasses by adding higher-density Ta2O5 instead of relatively low-density chemicals (ZnO and B2O3) and to examine the radiation shielding properties of these glasses. Therefore, the effect of Ta2O5 doping on gamma and neutron radiation shielding properties was investigated using Geant 4 Monte Carlo toolkit. It was observed that Ta2O5 doping increased radiation shielding properties significantly. Especially, the increase in gamma radiation shielding properties was determined to be more compared to the increase in neutron radiation shielding properties.

Investigation of neutron and gamma radiation protective characteristics of synthesized quinoline derivatives

Purpose Quinoline is formed by various natural compounds, such as alkaloids from the cinchona plant, which exhibit various biological activities, and is an important building material for the development of new drugs. Quinoline can be used in anti-radiation drug development but radiation interaction properties must be determined. Material and methods In this study, six types of synthesized quinoline derivatives were used. Fast neutron removal cross-section, mean free path, half value layer and transmission number were theoretically determined by using GEometry ANd Tracking 4 and FLUktuierende KAskade simulation codes for neutron shielding. Neutron dose absorption rates were determined using the 241Am-Be fast neutron source and the Canberra NP series portable BF3 gas proportional neutron detector. Gamma radiation shielding parameters were determined by using WinXCom and PSY-X/PSD software. Additionally, the genotoxic potentials of the derivatives were assessed by using the Ames/Salmonella bacterial reversion assay. Results and conclusions Neutron shielding parameters such as removal cross-section, mean free path, half value layer and transmission number were theoretically determined for fast neutrons. To determine neutron absorption capacity of quinoline derivatives, neutron absorption, experiments were conducted. In addition, gamma radiation shielding parameters were calculated such as the mean free path (MFP), mass attenuation coefficient (µt), half value thickness layer (HVL) and effective atomic number (Zeff) in the energy range of 0.015–15 MeV. The results of the all quinoline derivatives have excellent fast neutron shielding power compared to ordinary concrete. In addition, all quinoline derivatives have been found to have the capacity to attenuate gamma radiation. Moreover, they absorb well in both types of radiation, do not cause secondary radiation, and they are genotoxically safe at the tested concentrations. This study has demonstrated that these products can be used as active ingredients for a drug to be developed against radiation.

Attenuation of Gamma Radiation Using ClearView Radiation ShieldingTM in Nuclear Power Plants, Hospitals and Radiopharmacies

Radiation protection materials, such as lead (Pb), water, concrete, steel, and aluminum, have been successfully used for decades. Although they are effective shields, these materials do have limitations. For example, lead is heavy and toxic, and water and concrete must be thick to provide significant shielding, all of which renders these materials prohibitive for certain applications. For example, the half-value layer for water to shield against Co is 30.48 cm (12"), which makes it an extremely bulky material. The development of ClearView Radiation Shielding addresses some of the limitations that are faced by traditional radiation protection shields. The product is a transparent liquid gamma radiation shield that can be fabricated in custom sizes and thicknesses. Here, we describe applications of ClearView Radiation Shielding in nuclear plants and hospitals. ClearView Radiation Shielding is used to shield nuclear power plant workers from Co in critical path and high dose in refueling outages to observe automated operations inside the containment, and operations such as cylindrical frisking stations and benchtop sampling. ClearView Radiation Shielding is designed as rolling shields and radionuclide containments in hospitals to protect staff and families during unsealed radionuclide treatment such as MIBG and Lutetium therapies. For successful implementation in hospitals, the product was tested against various radioisotopes, also described in this work. Operational uses of ClearView Radiation Shielding in commercial nuclear and medical industries allows staff working in radioactive environments visibility, better communication and similar levels of radiation protection compared with traditional shielding materials. The product helps improve workflows and reduced total dose received by workers. Additionally, attenuation measurements using ClearView Radiation Shielding against multiple isotopes was performed. With 1.25 cm (0.5") ClearView Radiation Shielding thickness, the shield attenuated 1) 65% of the effective dose from I, 2) 35.15% of the effective dose from Cs, and 3) 22.5% of the effective dose from Co. Isotopes in the range of 35 keV to 1899 keV. 3.81 were attenuated greater than 90% with a ClearView Radiation Shielding shield thickness of 7.62 cm (3"). The half-value layer for Co with a ClearView Radiation Shielding thickness of 3.81 cm (1.5") attenuated the effective dose of F gammas by 85.59%. With a density of 2.3 g cm, ClearView Radiation Shielding was measured to be half the weight of lead for equal shielding. ClearView Radiation Shielding is transparent, lightweight, and an alternative material to conventional radiation shields to reduce radiation exposure.

Dy3+ doped SiO2–B2O3–Al2O3–NaF–ZnF2 glasses: An exploration of optical and gamma radiation shielding features

A series of Dy3+ doped zinc-aluminoborosilicate glasses with chemical composition 30SiO2-(30-x) B2O3–10Al2O3–15NaF–15ZnF2-xDy2O3 (x = 0, 0.5, 0.7, 1.0 and 1.5 mol %) were prepared by conventional melt-quenching method. Structural and optical properties of the glasses were analyzed through XRD, FTIR, UV–Visible–NIR and luminescence studies. Gamma radiation shielding parameters were obtained using PSD software. Nephelauxetic ratio (β) and bonding parameters (δ) calculated using absorption spectrum shows the decreasing ionic nature of the Dy ions. Judd-Oflet parameters (Ω2, Ω4 and Ω6) obtained shows the covalency and asymmetric nature of dysprosium ions. The luminescence properties shows that Dy3+ doped glasses have two strong intense emission at blue (482 nm) and yellow (575 nm) region. Branching ratio and stimulated emission cross section calculated suggests the glasses suitability to act as lasing material. CIE colour coordinates and its colour correlated temperature (CCT) for the glasses were estimated and found that these prepared glasses lie in the warm white light region.

Physical, optical and gamma radiation shielding competence of newly boro-tellurite based glasses: TeO2–B2O3–ZnO–Li2O3–Bi2O3

Herein, a traditional melt quenching method was utilized to synthesize glasses with a nominal chemical composition (80-x)TeO2-xB2O3–5ZnO–5Li2O3–10Bi2O3: 30≤ x ≤ 80 mol%). The produced sample was coded as TBBZL30 to TBBZL80. X-ray diffraction (XRD) has been employed to test the amorphous nature of the synthesized samples. In the range of 200–500 nm wavelength, UV–Vis spectra for the glasses have been performed. Optical energy gaps (Egap) have been determined based on the absorption measurements. With the help of (Egap), refractive index (n), molar polarizability (αM), metallization criterion (MCri.), molar refractivity (RM), static dielectric constant (εSta.), optical dielectric constant (εOpt.), reflection loss (RL) and optical transmission (TOpt.) have been calculated. For the fabricated boro-tellurite glasses, Phy-X/PSD was used to report some shielding factors for several energies between 15 keV and 15 MeV. The maximum attenuation for all samples took place at 15 keV and the mass attenuation coefficient varied between 52.309 and 57.084 cm2/g. The linear attenuation coefficient (LAC) results demonstrated that TBBZL80 has the highest attenuation than the rest of samples which is due to high content of TeO2 (containing 80 mol% of TeO2) whereas TBBZL30 has the lowest attenuation. The LAC for the fabricated samples varied between 230.160 and 351.064 cm-1 at 15 keV. The minimum effective atomic number (EAN) occurred between 0.8 and 4 MeV and varied between 15.16 and 17.35 for TBBZL30 and 25.10–28.33 for TBBZL80. The addition of TeO2 was found to enhance the EAN and improved shielding properties for the tested TBBZL glass systems.

Environment friendly La3+ ions doped phosphate glasses/glass-ceramics for gamma radiation shielding: Their potential in nuclear safety applications

Gamma-photon, neutron, and proton shielding parameters of La3+ ions doped multicomponent phosphate glasses/glass-ceramics of composition 50P2O5–30Sb2O3–10CaO–5Al2O3–5TeO2+xLa2O3 (La0–La5): x = 0–5 in steps of 1 mol% have been evaluated. These parameters were evaluated utilizing the WinXcom and EXABCal computer codes. Results revealed that the maximum values of MAC were 25.72, 26.85, 27.39, 27.91, and 28.41 cm2/g for La0–La5, respectively. Furthermore, the maximum and minimum values of LAC were obtained at 15 keV and 10 MeV, respectively with values of 91.82 and 0.107 cm−1, 94.67 and 0.108 cm−1, 98.55 and 0.111 cm−1, 101.62 and 0.113 cm−1, 105.22 and 0.115 cm−1, 107.96 and 0.116 cm−1. Values of HVL and MFP were varied according to the order (La5)HVL<(La4)HVL< (La3)HVL< (La2)HVL< (La1)HVL< (La0)HVL for all energies. The Zeff values were found to be maximum at 0.06 MeV and varied from 29.08 to 30.28 for La0 to La5, while the least values of Zeff were recorded at 1.5 MeV and varied from 14.88 to 15.53 for La0 to La5 samples. The buildup factors (B) at 15 MeV followed the trend (La0)B < (La1)B < (La2)B <(La3)B < (La4)B <(La5)B. The values of ΣR for fast neutrons were 0.0911, 0.0989, 0.1078, 0.1157, 0.1242, and 0.1316 cm−1 for La0– La5, respectively. The maximum range of proton was obtained at the maximum kinetic energy (10 MeV) having the values: 0.574, 0.569, 0.559, 0.553, 0.544, and 0.540 mm for La0– La5, respectively. Therefore, the increase of La3+ doping in La0–La5 samples has a positive influence on their radiation shielding capability. It can be concluded that, La0–La5 samples can attenuate photons, neutrons, alpha particles, and protons and as such, they can be applied successfully in nuclear shielding applications.

The f-factor, neutron, gamma radiation and proton shielding competences of glasses with Pb or Pb/Bi heavy elements for nuclear protection applications

In this article, proton, neutron, and gamma-ray shielding competences of six glasses with PbO or PbO/Bi2O3 heavy metal oxides namely as Glass 1 to Glass 6 have been investigated via WinXcom and EXABCal computer codes. The maximum values of μm were equal to 50.6, 53.06, 72.51, 80.67, 99.54, and 102.35 cm2 g-1 at 0.015 MeV for Glass 1 to Glass 6, respectively. The μm of the glass's trend in ascending order for Glass 1 to Glass 6. Results of HVL and MFP of the glass's were trend in descending order for Glass 1 to Glass 6. The Zeff of glasses varied from 14.49 (1.5 MeV) to 37.78 (0.1 MeV) and from 43.93 (2 MeV) to 65.62 (0.02 MeV) for Glass 1 and Glass 6, respectively. The f-factor of Glass 5 and Glass 6 was maximum for throughout the energy spectrum. The buildup factors are low and grow with the penetration depth rapidly up to the maximum depth of 40 mfp. The values of ΣR were varied from 0.0947 to 0.1155 cm−1 for Glass1 to Glass 6, respectively. Glass 2 and Glass 6 are preferred fast neutron shield when compared with ordinary concrete, water, and graphite. Generally, the molar concentration of PbO or PbO + Bi2O3 improved the shielding capacity of the investigated glasses.

Investigation of gamma ray shielding capability of fabricated clay-polyethylene composites using EGS5, XCOM and Phy-X/PSD

Gamma radiation shielding capability (GRSC) of the fabricated clay-polyethylene composites designated A, B, C, D, E, F and G containing 0, 5, 10, 15, 20, 25 and 30 wt %, respectively of recycled low density polyethylene (LDPE) were investigated. This was done by evaluating their radiation shielding parameters: the linear attenuation coefficient (LAC), mass attenuation coefficient (MAC), half value layer (HVL), tenth value layer (TVL) and mean free path (mfp) using a Monte Carlo simulation (EGS5 code) and Phy-X/PDS software. The values obtained for each parameter through each method are in good agreement. The effective atomic number (Zeff) of the composites was also estimated. Furthermore, the ambient dose rate and corresponding photon spectra at a distance of 20 cm for Am-241 source with 1 cm thickness ofthe selected Sample A and B were calculated. Though, the GRSC of the composites reduced as LDPE wt. % is increasing in the clay matrix yet the shielding effectiveness of the composites are found comparable or better, which indicates the suitability of the composites for gamma ray shielding applications.

The application of waste brass cartridges for gamma radiation shields and bullet proofing

This report shows the results of the investigations into the possible use of waste brass cartridges for gamma-ray shields and bullet proofing. The increasing usage of bullets and the almost inert nature of the resulting waste cartridges is an environmental concern that is pushing a rethink. Waste brass cartridges were collected from different military institutions and washed. Some of the cartridges were cut to required sizes and prepared for elemental composition, surface morphology and crystallographic analyses. The results showed that the waste cartridges contained appreciable amount of brass and therefore adequate for intended use. The waste brass cartridges were then processed into different sizes and thickness (5 mm, 10 mm, 20 mm) for the gamma radiation tests using both Thermal Neutron Spectroscope and NaI(Tl) Gamma Spectroscope. Ballistic tests were also conducted for different material thickness and shooting range up to 100 m. The results showed that the 5−20 mm thick processed waste brass plates successfully shielded gamma-rays of up to 150 keV as applicable in general practice. At increased radiation energy, the transmitted intensity was found to decrease with increased material thickness for all energy levels. Models for relating the energy transmittance and material thickness were developed for different energy source and intensity up to 1500 keV. The mixture of lead and reprocessed brass had excellent shielding properties too, however holes resulting from improper mixing were observed. The optimal processing procedure and mixing ratio of the brass with lead to reduce the usage of lead in radiation shielding in currently being investigated. In addition, the projectile penetrated the sample materials at investigated thicknesses and shooting range. Effort is currently on to enhance the processing and make it suitable as a material for bullet proof purposes.

Germanate oxide impacts on the optical and gamma radiation shielding properties of TeO2-ZnO-Li2O glass system

In this work, a series of tellurite glass combined with various concentrations of germanium oxide was fabricated according to the formula of (70-x)TeO2-xGeO2–20ZnO-10Li2O where x = 5, 10, 15 and 20 mol% via utilizing the melt-quench method for possible use in a radiation shielding applications. X-ray diffraction and Attenuated Total Reflectance Fourier Transform Infrared was employed to investigate the structure of the synthesized glasses. The density and Poisson's ratio for current samples reduced gradually from 5.221–5.008 g.cm−3 and 0.134–0.131, respectively, while the enhancement in bandgap values from 3.700–3.872 eV with addition of GeO2 is observed. The linear attenuation coefficient values at 0.015 MeV are 230.123 and 236.832 cm−1 for samples TG1 and TG4, respectively. Moreover, the lowest half-value layer attained via TG1 and raises from 0.0030 to 3.6684 cm while the highest HVL attained by TG4 and raises from 0.0029 to 3.9696 cm.