Half Value Layer Values Research Articles

Study on Radiation Shielding Properties of New Barium-Doped Zinc Tellurite Glass.

This study aimed to investigate the effect of BaF2 on the radiation-shielding ability of lead telluride glass. A physical radioactive source was used to estimate the mass attenuation coefficient (μm) of the 60TeO2-20PbO-(20-x)ZnO-xBaF2 glass system (where x = 1,2,3,5,6,7,9 mol%). We tested the μm values at seven energies (0.059, 0.081, 0.122, 0.356, 0.662, 1.173, 1.332 MeV). To determine the accuracy of the obtained results, we compared the experimental data with the data calculated using the XCOM software. The experimental values obtained for the selected lead telluride glasses at different concentrations of BaF2 are in good agreement with the results of XCOM at all energies. The addition of BaF2 increased the μm value of the sample. At the same time, the half-value layer (HVL), mean free path (MFP), effective atomic number (Zeff), and fast neutron removal cross-section (RCS) of the glass were studied. With the increase in the BaF2 content, the HVL value and MFP value of the glass decreased, and the Zeff value and RCS increased, indicating that the addition of BaF2 enhanced the radiation-shielding performance of the glass.

Effect of TeO2 addition on the gamma radiation shielding competence and mechanical properties of boro-tellurite glass: an experimental approach

We experimentally investigated the effect of TeO2 on the radiation-shielding competence of a BaO–MoO3–B2O3 glass system. Two gamma-ray sources (137Cs and 166Ho) and a scintillator detector (sodium iodide (NaI(Tl)) were utilized to measure the attenuation factors of the prepared glass at 0.184, 0.280, 0.662, 0.710, and 0.810 MeV. The measured mass attenuation coefficient agreed well with the theoretically calculated values for all the prepared samples. The linear attenuation coefficient (LAC) results demonstrated that as the photon energy increased, the penetrating ability of the photons through the glass increased. The LAC values of boro-tellurite glass at 662 keV were compared with those of other tellurite glass. We found that MTB1 glass produced better attenuation results than 10Li2O–20K2O–50B2O3–20TeO2 glass, whereas MTB5 glass with 70 mol% TeO2 had an LAC value greater than that of 90.4TeO2-9.6ZnO–4NiO glass. The half-value layer (HVL) increased continuously with photon energy. For MTB1 glass, the HVL increased from 0.3609 cm at 184 keV to 1.6078 cm at 662 keV and 1.8381 cm at 810 keV. The lowest set of HVL values was observed for MTB5 glass, which confirmed its superior attenuation properties compared to other compositions. The transmission factor (TF) was also calculated; MTB5 glass had the lowest TF values, which revealed that MTB5 provided the best shield. For glass with a thickness of 1 cm, the TF was 75.8% for MTB1, 72.8% for MTB2, 70.6% for MTB3, 68.8% for MTB4, and 63.4% for MTB5.

Heavy metal oxide (HMO) glasses as an effective member of glass shield family: A comprehensive characterization on gamma ray shielding properties of various structures

Using advanced Monte Carlo simulation techniques and theoretical methodologies, a thorough investigation on the gamma-ray shielding properties of several heavy metal oxide glasses were performed. The general-purpose Monte Carlo code MCNPX (version 2.7.0) was used to simulate gamma-ray transmission to determine fundamental attenuation coefficients. The acquired findings were compared to Phy-X/PSD to confirm that the outputs were consistent. Additionally, other gamma-ray shielding parameters were computed and studied throughout a broad photon energy range of 0.015 MeV–15 MeV. From A to F glass samples, a sharp density increase from 5.99 g/cm3 to 8.9 g/cm3 was found. As a result, the F sample was found to have the highest linear attenuation coefficients. Our results indicate that increasing the amount of Bi reinforcement improved the material's overall gamma-ray attenuation properties. The F sample with the highest Bi reinforcement in its glass structure was subsequently shown to have superior gamma-ray shielding characteristics. Finally, we compared the F sample's half-value layer values to those of other commercial glass shields, various concretes, and other glass shields investigated in the literature. As a consequence of the benchmarking procedure, it has been determined that the F sample has better shielding capabilities than other shielding materials. It can be concluded that heavy metal oxide glasses offer apparent benefits in terms of more efficiently attenuating incoming gamma-rays. Additionally, it can be concluded that applying high Bi to heavy metal oxide glasses is a beneficial strategy for improving the gamma-ray attenuation capabilities of heavy metal oxide glasses.

Experiment of a Dedicated Lead Slit for X-ray Output Analyzer in X-ray CT Half-value Layer Measurements

It is not easy to measure the half-value layer (HVL) of CT because it is necessary to place the X-ray tube position fixed. The aim of this study was to experiment the new methods of HVL measuring of CT using a custom-made lead slit. The custom-made lead slit method allowed the HVL measuring of CT while the rotation of the X-ray tube. The error of HVL value using the custom-made lead slit method compared to the conventional method was within 6%. The custom-made lead slit method can enable to measure the HVL of CT easily without the X-ray tube position fixed.

A detailed investigation on highly dense CuZr bulk metallic glasses for shielding purposes

Abstract Gamma-ray shielding properties of eight different metallic glasses based on CuxZr100-x: x = 35 (Cu35Zr65) − 70 (Cu70Zr30) were determined using Monte Carlo simulations and Phy-X/PSD software. A typical gamma-ray transmission setup has been modeled in MCNPX Monte Carlo code. The general trend of the linear attenuation coefficients (μ) was reported as (μ)Cu35Zr65 < (μ)Cu40Zr60 < (μ)Cu45Zr55 < (μ)Cu50Zr50 < (μ)Cu55Zr45 < (μ)Cu60Zr40 < (μ)Cu65Zr35 < (μ)Cu70Zr30. In terms of half value layer (HVL) values, the Cu35Zr65 sample has the highest value (2.984 cm) and the Cu70Zr30 sample has the lowest value (2.769 cm) at 8 MeV photon energy. The mean free path (MFP) values were 4.305 and 3.995 cm for Cu35Zr65 and Cu70Zr30 samples, respectively. Generally, MFP and HVL values of the studied glasses were reported as (MFP,HVL)Cu35Zr65 > (MFP,HVL)Cu40Zr60 > (MFP,HVL)Cu45Zr55 > (MFP,HVL)Cu50Zr50 > (MFP,HVL)Cu55Zr45 > (MFP,HVL)Cu60Zr40 > (MFP,HVL)Cu65Zr35 > (MFP,HVL)Cu70Zr30 for all photon energy range. The Cu70Zr30 sample showed maximum values of both the effective conductivity (C eff) and effective electron density (N eff). In addition, the Cu70Zr30 sample has minimum exposure and energy absorption buildup factor (EBF and EABF) values at all studied gamma-ray energies. The results revealed that the Cu70Zr30 sample has superior attenuation properties among all studied samples.

Novel Shielding Mortars for Radiation Source Transportation and Storage

New types of mortar, M1 (60% sand, 25% cement, 10% ball clay, and 15% WO3), M2 (50% sand, 25% cement, 10% ball clay, and 25% WO3), M3 (60% sand, 25% cement, 10% Barite, and 15% WO3), and M4 (50% sand, 25% cement, 10% Barite, and 25% WO3), were prepared and the impact of WO3 and barite on their radiation shielding performance and mechanical properties was evaluated. The radiation attenuation factors were evaluated using five radioactive point sources, and a sodium iodide (NaI) scintillation detector (3″ × 3″) was used to detect the attenuation of gamma ray photons emitted from radioactive sources. The density values of the mortar samples lie within the range of 2.358 and 2.602 g/cm3. The compressive strength and the tensile strength of the prepared mortars increased with the increasing percentage of WO3. The M4 mortar had the highest linear attenuation coefficient (LAC) value. The LAC results demonstrated that adding barite and a high percentage of WO3 into the mortars notably enhanced the radiation shielding performance of the prepared mortar. The relationship between the half value layer (HVL) and the energy is direct, and so was used to calculate the thickness of mortar needed to absorb or scatter half the number of low-energy photons falling on the samples. At 0.06 MeV, the HVL values of the samples were 0.412, 0.280, 0.242, and 0.184 cm for samples M1–M4, respectively. The highest HVL values, obtained at 1.408 MeV, were 5.516, 5.202, 5.358, and 5.041 cm. Thus, a thinner layer of the M4 sample provided comparable attenuation of photons and radiation protection to the thicker M1–M3 samples. The new material is promising as an effective shield of radiation-emitting sources during transportation and long-term storage.

Impact of the gamma and neutron attenuation behaviors on the functionally graded composite materials

Gamma-ray and neutron shielding properties of the AA6082 + TiO2 (0–50 wt%) functionally graded composite materials (FGCMs) were investigated using the PSD software. The values of the mean free path (MFP), half-value layer (HVL), linear attenuation coefficients (LAC), mass attenuation coefficient (MAC), tenth-value layer (TVL), exposure buildup factors (EBF), effective atomic number (Z eff ), effective conductivity (C eff ), and fast neutron removal cross-sections (FNRC) were found for the energy range between 0.015–15 MeV. The increase in the TiO2 content in the AA6082 composite material has raised the values of MAC and LAC. The calculations for the EBFs were carried out using the G-P fitting method for the energy range between 0.015–15 MeV and penetration depth of up to 40 mfp. The results revealed that HVL values ranged between 0.01–0.116 cm, TVL values ranged between 0.01–0.385 cm, FNRC values ranged between 7.918–10.017 cm−1, and C eff values ranged between 5.67 × 1010 and 9.85 × 1010 S m−1. The AA6082 + TiO2 (50%) composite material was observed to provide the maximum photon and neutron shielding capacity since it offered the highest Z eff , MAC, and FNRC values, and the lowest HVL value. In terms of several aspects, the research is considered original. Besides contributing to several technologies including nanotechnology and space technologies, present research’s results may contribute to nuclear technology.

Simulation and prediction of the attenuation behaviour of the KNN–LMN–based lead-free ceramics by FLUKA code and artificial neural network (ANN)–based algorithm

ABSTRACT The significance and novelty of the present work are the preparation of the non-lead ceramic by the general formula of (1-x) K0.5Na0.5NbO3-xLa Mn0.5Ni0.5O3 (KNN–LMN) with different x (0<x<0.295) (mol) to examine the shielding qualities of KNN–LMN non-lead ceramic via FLUKA code. The obtained results via FLUKA code are used as input data for training the artificial neural network algorithm and prediction. For this purpose, the radio isotopic 252Cf neutron source is simulated by the HI-PROBE, RADDECAY and DCYSCORE cards using the FLUKA code. As a result, the neutron–gamma photon shielding ability of the KNN–LMN lead-free ceramics exposed to the 252Cf neutron source is estimated and predicted. Findings show that by increasing the concentration of the x in (1-x) K0.5Na0.5NbO3-xLa Mn0.5Ni0.5O3 lead-free ceramics results in an ascending trend in density. In addition, the increment of the x rate (x refers to the concentration of La Mn0.5Ni0.5O3 in KNN–LMN non-lead ceramics) causes an increase in the value of the neutron attenuation parameter (), and a strong relationship is monitored between and density. Moreover, descending order of is reported for half-value layer values against gamma photon. From the attained results, it can be concluded that increaisng the rate of x results in the better shielding proficiency in terms of neutron and gamma photon for chosen KNN–LMN–based lead-free ceramics.

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 Z, effective electron density N and half-value layer (HVL) of four types of surgical-grade stainless steel were determined via the mass attenuation coefficient . The coefficients were determined experimentally using an X-ray fluorescence (XRF) technique and theoretically via the WinXCOM program. The K 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 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 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 at the energies 21.20, 22.19 and 25.29 keV. In addition, the measured results of Z and N 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 (Z) 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 , Z and Z 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.

Analysis of physical and mechanical traits and nuclear radiation transmission aspects of Gallium(III) trioxide constituting Bi2O3-B2O3 glasses

For five Ga2O3-Bi2O3-B2O3 composition glasses for improved Bi2O3 content at 25 to 65 mol% (10% continuously each time) at a fixed 10 mol% Ga2O3 amount, distinct physical and mechanical aspects and nuclear radiation attenuation factors were investigated. Increased Λ (optical basicity) values with a gradual Bi2O3 addition indicate studied samples’ improving basic character. Applying BC (bond compression) model key mechanical traits such as Ybc (Young’s modulus), Kbc (bulk modulus), S (shear modulus), L (longitudinal modulus), and σ (Poisson’s ratio) are evaluated where in all glasses 10Ga2O3-65Bi2O3-25B2O3 (mol%) sample exhibits superior elastic moduli. Enhanced Bi2O3 causes for compactness of the gallium borate network as ǹc (average cross-link density) improves from 2.3 to 3.4 indicating increased rigidity of glasses. Later, PHITS, FLUKA, and MCNPX codes are wielded to derive μ/ρ (mass attenuation coefficient) of all selected samples for photons having energy ranging from 15 KeV to 15 MeV. Simulated μ/ρ quantities exactitude is tested via Phy-X/PSD and WinXCOM programs’ μ/ρ results and identified a fairly good harmony among them. With photon energy, MFP (mean free path), TVL (tenth-value layer), and HVL (half-value layer) values variations show a similar tendency and against the trend which noticed for μ/ρ and μ (linear attenuation coefficient) values. 10Ga2O3-65Bi2O3-25B2O3 (mol%) sample’s MFP and HVL are correlated with five commercial γ-ray glass shields’ respective values at 1.25 MeV, 0.662 MeV (137Cs), and 0.2 MeV energies. Further, Zeq (equivalent atomic number) and using G–P (geometric progression) fitting approach for ten individual PDs (penetration depths) within 1–40 mfp range at 15 – 15 × 103 KeV energy region BUFs (buildup factors) were estimated. Attained RPE (radiation protection efficiency) findings attest all chosen Ga2O3-Bi2O3-B2O3 glasses’ competent absorption capacity for lower energy photons. Next, α-particles and protons MSPs (mass stopping powers), i.e. ΨA and ΨP and PRs (projected ranges), i.e. ΦA and ΦP by utilizing SRIM code as well as for electrons MSPs (ΨE) and CSDA (continuous slowing‐down approximation) ranges by ESTAR database have been calculated within 15–15 × 103 KeV KE (kinetic energy) range. Also, ΣR (fast neutron removal cross-section) and for 0.253 × 10–4 KeV energy neutrons σT (total cross-section) and SP (shielding percentage) values were approximated. With Bi2O3 addition, realized ΣR is changed at 0.1161–0.1213 cm−1 extent. For thermal neutrons absorption, 10Ga2O3-25Bi2O3-65B2O3 (mol%) glass shows larger σT (=17.534 cm−1) and at any considered thickness higher SP whereas 10Ga2O3-65Bi2O3-25B2O3 (mol%) (lead-free) glass has better attenuating features for photons affirming the incorporated Bi2O3 favorable effect.

X-ray radiation shielding of CeO2 doped borosilicate glasses and their luminescence characteristics

The novel shielding materials from (55-x) SiO2: 13B2O3: 1Al2O3: 4.5BaO: 6.3CaO: 0.2Sb2O3: 20Na2O: xCeO2 where x = 1, 2, 3, 4 and 5 mol% glasses have been fabricated at different CeO2 concentration by melt-quenching technique and studied the luminescence and radiation shielding properties. The transmission spectra show red-shift in UV range, due to higher Ce concentration in the glass matrix. The emission bands of glasses around 393 nm were observed from the 5d-4f transition of an electron in the Ce3+ ion. In the present glass matrix doped with CeO2 shows oxidation state of both Ce3+ and Ce4+. Decay curves are also investigated and found to be less than 100 ns. The X-rays shielding properties such as half-value layer (HVL), tenth value layer (TVL), mean free path (MFP), and linear attenuation coefficients (μ) of glass were investigated. The HVL values of glass samples at 5 mol% has better shielding behavior than commercial x-ray windows. The obtained results from the measurements suggests that these glasses are potential host for radiation shielding material application and also UV emitting device applications.

Manufacture of Shielding for Attenuation Ionization Ray by the Preparation of Nano Gadolinium Oxide with PMMA

In this research, the coefficient of linear absorption, Half-value layer and Effective atomic number of the composite material for gamma ray of gadolinium oxide with PMMA (Gd2O3- PMMA) for shields made with varying concentrations (10%, 20%, 30%, 40%) and varied thicknesses The impact of raising the shield thickness when the concentration of each thickness is increased. The gamma ray radiation source was Cs-137and Co-60 which have (activity 10 μci and energy of 0.662 MeV, activity 1μci and energies 1.173 -1.332 (MeV) were used in measurement, As an electrical system, a scinatelaion detector (NaI (Tl)) was utilized with a (2x2)" for ORTEC software program (Scintivision-Buffer) with an integrated measurement system. The results reveal that when the concentration of nano particle-gadolinium oxides raised and the thickness of the produced layer increased, the attenuation coefficient and effective atomic number values increased of the prepared composite However, as the concentration and thickness of the composite increased, the Half-value layer values dropped.

An Investigation on Radiation Shielding Properties of Borosilicate Glass Systems

The aim of this research is to examine the radiation shielding properties of 5B2O3-40SiO2-(55-x)Al2O3-xBaO (BSABa-x) glass systems, which are containing barium and aluminum oxide added to borosilicate glasses, with varying from 25 to 34 weight fractions. Shielding parameters, such as linear attenuation coefficients (LAC), mass attenuation coefficients (MAC), mean free path (MFP), effective atomic number (Zeff), effective electron density (Neff), half-value layer (HVL), tenth-value layer (TVL), effective atomic weight (Aeff), exposure buildup factors (EBF) and energy absorption buildup factors (EABF) enable us to obtain information about the radiation shielding power of composite glass material groups. Therefore, the mass attenuation coefficients (MAC), for the 0.015–15 MeV gamma-ray energies are obtained by using the Py-MLBUF online software to determine photon shielding parameters of BSABa-x glasses. The results are shown that the glass which contains higher BaO concentration has higher mass attenuation coefficients. BSABa-34 glass has the highest MACs, ranging from 0.111 cm2/g to 90.400 cm2/g, while BSABa-25 glass has the lowest values, ranging from 0.099 cm2/g to 69.000 cm2/g. The BSABa-34 glass with the highest BaO contribution has the thinnest MFP and HVL values. In addition, photon buildup is minimized by adding BaO to the BSABa-x glasses. Accordingly, we can conclude that adding BaO to aluminum borosilicate glasses at increasing rates, improves nuclear radiation resistance properties.

Synthesis of barium-doped PVC/Bi2WO6 composites for X-ray radiation shielding

In this study, composites containing undoped and barium-doped Bi2WO6:Ba2+were investigated for their shielding against diagnostic X-ray. At first, Bi2WO6 and barium-doped Bi2WO6 were synthesized with different weight percentages of barium oxide through a hydrothermal process. The as-synthesized nanostructures were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) and Raman spectroscopy (RS). After that, some shields were generated with undoped and barium-doped Bi2WO6:Ba2+ nanostructure particles incorporated into polyvinyl chloride (PVC) polymer with different thicknesses and 15% weight of the nanostructure. Finally, the prepared samples were exposed to an X-ray tube at 40, 80, and 120 kV voltages, 10 mAs and, 44.5 cm SID (i.e. the distance from the X-ray beam source to the specimen). Linear and mass attenuation coefficients were also calculated for different samples. The results indicated that, among the samples, the one with 7.5 mmol barium-doped Bi2WO6 had the most attenuation at the voltage of 40kV, and the attenuation coefficients would increase with an increase in the amount of barium. The samples with 15 and 17.5 mmol barium-doped Bi2WO6 had higher attenuation than the others at 80 and 120 kV. Moreover, the half-value layer (HVL), tenth-value layer (TVL) and 0.25 mm lead equivalent thickness were calculated for all the samples. The lowest HVL value was for the sample with 7.5 mmol barium-doped Bi2WO6. As the result clearly show, an increment in the barium-doping content leads to a decrease in both HVL and TVL.In every three voltages, 0.25 mm lead equivalent thickness of the barium-doped composites (7.5 mmol and 15 mmol) had less than the other composites. The lowest value of 0.25 mm lead equivalent thickness was 7.5 barium-doped in 40 kV voltage and 15 mmol barium-doped in 80 kV and 120 kV voltages. These results were obtained only for 15% weight of the nanostructure.

Calculation of X-ray spectra characteristics and kerma to personal dose equivalent Hp(10) conversion coefficients: Experimental approach and Monte Carlo modeling

This work aims to establish some X-ray qualities recommended by the International Standard Organization (ISO) using the half-value layer (HVL) and Hp(10) dosimetry approaches. The HVL values of the following qualities N-60, N-80, N-100, N-150 and N-250 were determined using various attenuation layers. The obtained results were compared to those of reference X-ray beam qualities and a good agreement was found (difference less than 5% for all qualities). The GAMOS (Geant4-based Architecture for Medicine-Oriented Simulations) radiation transport Monte Carlo toolkit was employed to simulate the production of X-ray spectra. The characteristics HVLs, mean energy and the spectral resolution of simulated spectra have been calculated and turned out to be conform to the ISO reference ones (difference less than the limit allowed by ISO). Furthermore, the conversion coefficients from air kerma to personal dose equivalent for simulated and measured spectra were fairly similar (the maximum difference less than 4.2%).

Experimental and Theoretical Study of Radiation Shielding Features of CaO-K2O-Na2O-P2O5 Glass Systems.

The gamma radiation shielding ability for CaO-K2O-Na2O-P2O5 glasses were experimentally determined between 0.0595 and 1.41 MeV. The experimental MAC results were compared with theoretical results obtained from the XCOM software to test the accuracy of the experimental values. Additionally, the effect of increasing the P2O5 in the glass composition, or reducing the Na2O content, was evaluated at varying energies. For the fabricated glasses, the experimental data strongly agreed with the XCOM results. The effective atomic number (Zeff) of the fabricated glasses was also determined. The Zeff values start out at their maximum (12.41–12.55) at the lowest tested energy, 0.0595 MeV, and decrease to 10.69–10.80 at 0.245 MeV. As energy further increases, the Zeff values remain almost constant between 0.344 and 1.41 MeV. The mean free path (MFP) of the fabricated glasses is investigated and we found that the lowest MFP value occurs at the lowest tested energy, 0.0595 MeV, and lies within the range of 1.382–1.486 cm, while the greatest MFP can be found at the highest tested energy, 1.41 MeV, within the range of 8.121–8.656 cm. At all energies, the KCNP40 sample has the lowest MFP, while the KCNP60 sample has the greatest. The half value layer (HVL) for the KCNP-X glasses is determined. For all the selected energies, the HVL values follow the order of KCNP40 < KCNP45 < KCNP50 < KCNP55 < KCNP60. The HVL of the KCNP50 sample increased from 0.996 to 2.663, 3.392, 4.351, and 5.169 cm for energies of 0.0595, 0.245, 0.444, 0.779, and 1.11 MeV, respectively. The radiation protection efficiency (RPE) results reveal that decreasing the P2O5 content in the glasses improves the radiation shielding ability of the samples. Thus, the KCNP40 sample has the best potential for photon attenuation applications.

Investigation of the suitability of new developed epoxy based-phantom for child's tissue equivalency in paediatric radiology

In this study, tissue equivalency (TE) of a newly developed epoxy-based phantom to 3–5 years child's tissue was investigated in paediatric energy range. Epoxy-based TE-phantoms were produced at different glandular/adipose (G/A) ratios of 17/83%, 31/69%, 36/64% and 10/90%. A procedure was developed in which specific amounts of boron, calcium, magnesium, sulphur compounds are mixed with epoxy resin, together with other minor substitutes. In paediatric energy range of 40–60 kVp half-value layer (HVL) values were measured and then Hounsfield Units (HU) were determined from Computed Tomography(CT) scans taken in the X-ray energy range of 80-120kVp. It is found that radiation absorption properties of these phantoms in terms of the measured HVL values related to linear attenuation coefficients (μ) are very well mimicking a 3 years child's soft tissue in case a ratio of 10/90%G/A. Additionally, the HU values of phantoms were determined from the CT scans. The HU = 47.8 ± 4.8 value was found for the epoxy-based phantom produced at a ratio of 10/90%G/A. The obtained HVL and HU values also support the suitability of the new epoxy based-phantom produced at a ratio of 10/90%G/A for a satisfactory mimicking a 3 years child's soft tissue by 5%. Thus they can have a potential use to perform the quality controls of medical X-ray systems and dose optimization studies.

The photon interactions and build-up factor for gadolinium sodium borate glass: Theoretical and experimental approaches

Gadolinium sodium borate glass in compositions of xGd2O3: 20Na2O:(80-x)B2O3 (where x is 0, 5, 10, 15, and 20 mol%) were prepared by melt quenching technique. The glass samples have been investigated for the physical properties and radiation shielding properties. The glass density and molar volume tended to increase with increasing Gd2O3 concentration. The theoretical values of radiation shielding were computed by WinXCom program in the energy range 0.015 MeV–15 MeV. The experimental values have been measured in energy range 0.223 MeV–0.662 MeV using Compton scattering technique for variation the energy from Cs-137 source. The experimental values are in good agreement with the theoretical values. From the results, the replacement of B2O3 by Gd2O3 helped to increase the mass attenuation coefficients (μm), effective atomic number (Zeff) and effective electron density (Neff). The energy absorption buildup factor coefficients (EABF) and the exposure buildup factor values (EBF) were decreased with the increasing of Gd2O3 at energy below 2 MeV and show the increase with Gd2O3 content at energy higher than 2 MeV. The half value layer (HVL) were decreased with increasing of Gd2O3. All studied glasses were found to be lower HVL values, when compared with the some standard shielding materials. These results reflected to the ability of gadolinium sodium borate glass for radiation shielding material.

Characterization of optical and radiation shielding behaviors of ferric oxide reinforced bismuth borate glass

This study aimed to investigate the ferric oxide effect on optical and radiation shielding behaviors of bismuth borate glasses. Gamma-ray attenuation competencies of six glass samples along with optical properties were investigated in terms of their utilization suitability as a shield or personal protection equipment in industrial and medical fields. The chemical composition (60-x) B2O3 + 20Bi2O3 + 20Li2O+xFe2O3 with different Fe2O3 concentrations were prepared using the melt-quenching technique. Gamma-ray attenuation competencies of six glass samples along with optical properties were investigated in terms of their utilization suitability in industrial and medical fields. The outcomes of optical investigations indicated that direct optical band gap (Eg direct) decrease from 5.11 eV to 4.82 eV, while for indirect transition (Eg indirect) decrease from 4.62 eV to 3.79 eV, with increasing Fe2O3 concentrations. To determine the radiation shielding performance, mass attenuation coefficients (μ m) of samples were calculated using FLUKA code and XCOM program between 0.015–15 MeV photon energy range. Accordingly, gamma shielding parameters such as mass (MAC) and linear (LAC) attenuation coefficients, half-value layer (HVL), tenth value layer (TVL), mean free path (MFP), effective atomic numbers (Zeff), electron density (Nel), and fast neutron removal cross sections (ΣR) were evaluated for all glass samples. The results showed that increasing Fe2O3 concentration in glass structure increased the MAC and Zeff. The Fe-10 was reported with the lowest HVL values in addition to the highest MAC and Zeff values.

Determination of transmission curves of X-ray spectra for contrast-enhanced digital mammography using Monte Carlo simulations

To determine transmission curves of X-ray broad beams through common shielding materials, for the contrast-enhanced digital mammography (CEDM) imaging technique, using Monte Carlo simulations. Simulations were performed for anode/filter combinations of W/Rh and W/Ag, for tube potentials between 25 and 35 kVp, employed for low energy (LE) imaging, and for W/Cu, W/Ti and Mo/Cu between 35 and 49 kVp, for high energy (HE) imaging. Fitting parameters for each transmission curve were also obtained. Transmission curves were simulated using the Monte Carlo code PENELOPE. The geometric model adopted was composed by the breast compression paddle and the following common shielding materials: lead, steel, plate glass, concrete, gypsum, and wood. The obtained curves were fitted to the Archer equation, in order to determine their fitting parameters α, β, and γ. Transmission curves for LE and HE spectra showed different behaviors. On average, values of half-value layer at high attenuation for LE spectra, at 35 kVp, are 2.36 times greater than those at 25 kVp, while for HE spectra, at 49 kVp, excepting for wood, are 2.39 times greater than those at 35 kVp. Results for fitting parameters showed that α values decrease with tube potential, whereas the behavior of β and γ values depends on the spectrum and shielding material. The results obtained and the fitting parameters provided can be useful for evaluating the shielding design of this technique, since there are significant differences between results for the LE and HE spectra, evidentiating the importance of considering appropriate transmission data.