Exploring the Radioprotective Indium (III) Oxide Screens for Mammography Scans Using a Three-Layer Heterogeneous Breast Phantom and MCNPX: A Comparative Study Using Clinical Findings.

Background: During mammography, a lead-acrylic protective screen is recommended to reduce radiation exposure to the unexposed breast. Objectives: This research study aimed to construct an Indium-(III)-oxide-rich tellurite-glass screen (TZI8) and compare its performance to that of lead acrylic. Materials and Methods: A three-layer heterogeneous-breast phantom was developed, using the MCNPX (version 2.7.0) Monte Carlo code. An MCNPX-simulation geometry was designed and implemented, using the lead-acrylic and TZI8 shielding screens between the right and left breast. Next, the reliability of the phantom and the variations in absorption between the lead-acrylic and TZI8 glass were investigated. Results: The findings show that the TZI8-protective-glass screen offers significantly greater radioprotection than the lead-acrylic material. The quantity of total dose absorbed in the unexposed breast was much lower for TZI8 than for lead-based acrylic. The TZI8-glass screen gives about 60% more radioprotection than the lead-acrylic screen. Conclusion: Considering the toxic lead in the structure that may be hazardous to the human tissues, the TZI8-glass screen may be used in mammography examination to provide greater radioprotection than the lead-acrylic screen, in order to greatly reduce the dose to the unexposed breast.

Establishment of Diagnostic Reference Levels in Cone Beam Computed Tomography Scans in the United Arab Emirates.

This study aimed to address the knowledge gap in assessing the radiation doses from cone beam computed tomography (CBCT) procedures, establishing a typical value, and estimating effective and organ doses. A total of 340 patients aged 18-80 years were included in this study. Organ doses were estimated using VirtualDose IR software. The typical values were based on median values estimated as 1000 mGy cm2. The mean ED (µSv) per procedure was 149.5 ± 56, and the mean of the peak skin dose during the CBCT examination was 39.29 mGy. The highest organ dose was received by the salivary glands (2.71 mGy), the extrathoracic region (1.64 mGy), thyroid (1.24 mGy) and eyes (0.61 mGy). The patients' doses were higher than in previous studies. Staff awareness, education, training and dose optimisation are highly recommended. With the establishment of local DRLs, patient dosages can be reduced successfully without compromising image quality.

A Comprehensive Evaluation of the Attenuation Characteristics of Some Sliding Bearing Alloys under 0.015-15 MeV Gamma-Ray Exposure.

In this study, three different sliding bearing alloy samples were investigated in terms of their performance on attenuation characteristics and behavioral attitudes under 0.015-15 MeV gamma-ray exposure. Accordingly, different types of advanced calculation methods were utilized to calculate the radiation shielding parameters. Next, several gamma-ray shielding parameters and exposure rates in addition to fast neutron removal cross-section were determined. Furthermore, exposure and energy absorption buildup factors were determined by using G-P fitting method. Mass attenuation coefficients (MAC) values were recorded as 2.5246, 2.5703, and 2.5827 (cm2/g) for Alloy1, Alloy2, and Alloy3 samples at 15 MeV photon energy, respectively. At 40 mfp, the highest EBF values were reported as 1,376,274, 1,003,593, and 969,373 for Alloy1, Alloy2, and Alloy3 samples. The results of this extended investigation showed that the Alloy3 sample with the highest Pb reinforcement amount has superior shielding capability among the investigated samples. It can be concluded from the results that substitution of Pb with Bi in the recent alloy structure has a monotonic effect on different types of shielding parameters. Therefore, it can also be concluded that Pb is a remarkable tool for the improvement of the shielding properties of studied alloy structures.

Gamma-Ray Protection Properties of Bismuth-Silicate Glasses against Some Diagnostic Nuclear Medicine Radioisotopes: A Comprehensive Study.

This study aimed to perform an investigation for the potential implementation of bismuth silicate glasses as novel shield equipment instead of ordinary shields in nuclear medicine facilities. Accordingly, a group of Bi2O3 reinforced silicate glass system were investigated and compared with ordinary shields in terms of their gamma-ray attenuation properties in diagnostic nuclear medicine radioisotope energies emitted from 99mTc, 111In, 67Ga, 123I, 131I, 81mKr, 201Tl, 133Xe. Mass attenuation coefficient (µm) results for glass samples were calculated comparatively with the XCOM program and MCNPX code. The gamma-ray attenuation parameters such as half value layer (HVL), tenth value layer (TVL), mean free path (MFP), effective atomic number (Zeff) were obtained in the diagnostic gamma ray energy range from 75 to 336 keV. To confirm the attenuation performance of superior sample, obtained results were extensively compared with ordinary shielding materials. According to the results obtained, BISI6 glass sample with the highest Bi2O3 additive has an excellent gamma-ray protection.

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.

A Closer Look on Nuclear Radiation Shielding Properties of Eu3+ Doped Heavy Metal Oxide Glasses: Impact of Al2O3/PbO Substitution.

In this study, a group of heavy metal oxide glasses with a nominal composition of 55B2O3 + 19.5TeO2 + 10K2O + (15-x) PbO + xAl2O3 + 0.5Eu2O3 (where x = 0, 2.5, 5, 7.5, 10, 12.5, and 15 in wt.%) were investigated in terms of their nuclear radiation shielding properties. These glasses containing lanthanide-doped heavy metal oxide were envisioned to yield valuable results in respect to radiation shielding, and thus a detailed investigation was carried out; the obtained results were compared with traditional and new generation shields. Advanced simulation and theoretical methods have been utilized in a wide range of energy regions. Our results showed that the AL0.0 sample with the highest PbO contribution had superior shielding properties in the entire energy range. The effective removal of cross-sections for fast neutrons (ΣR) was also examined. The results indicated that AL5.0 had the greatest value. While increasing the concentration of Al2O3 in samples had a negative effect on the radiation shielding characteristics, it can be concluded that using PbO in the Eu3+ doped heavy metal oxide glasses could be a useful tool to keep gamma-ray shielding properties at a maximum level.

Novel Cu/Zn Reinforced Polymer Composites: Experimental Characterization for Radiation Protection Efficiency (RPE) and Shielding Properties for Alpha, Proton, Neutron, and Gamma Radiations.

In this study, brass (Cu/Zn) reinforced polymer composites with different proportions of brass powders were fabricated. Different types of nuclear shielding parameters such as mass and linear attenuation coefficients, radiation protection efficiency, half and tenth value layers, and effective atomic number values were determined experimentally and theoretically in the energy range of 0.060-1.408 MeV in terms of gamma-ray shielding capabilities of fabricated polymer composites. A high Purity Germanium detector (HPGe) in conjunction with a Multi-Channel Analyzer (MCA) and twenty-two characteristic gamma-ray energies have been used in the experimental phase. In addition, the exposure and energy absorption buildup factors of reinforced Cu/Zn composites were calculated, and relative dose distribution values were computed to verify them. Proton mass stopping power (ΨP), proton projected range (ΦP), alpha mass stopping power (ΨA), and alpha projected range (ΦA) parameters, which indicate the interactions of the produced composites with charged particle radiation, were investigated. Fast neutron removal cross-section (ΣR) results were determined to give an idea in terms of neutron shielding. According to the obtained results, it is reported that the CuZn20 coded sample's ability to attenuate gamma-ray and charged particle radiation is more efficient than that of other prepared composites. A CuZn05 coded sample was found to be more suitable for neutron shielding capability.

Exploring the FTIR, Optical and Nuclear Radiation Shielding Properties of Samarium-Borate Glass: A Characterization through Experimental and Simulation Methods.

(Tl2O3)30-(Li2O)10-(B2O3)(60-y)-(Sm2O3)y glass system with various Sm2O3 additives (y = 0, 0.2, 0.4, 0.6) was studied in detail. The vibrational modes of the (Tl2O3)30-(Li2O)10-(B2O3)(60-y) network were active at three composition-related IR spectral peaks that differed from those mixed with Samarium (III) oxide at high wavenumber ranges. These glass samples show that their permeability increased with the Samarium (III) oxide content increase. Additionally, the electronic transition between localized states was observed in the samples. The MAC, HVL, and Zeff values for radiation shielding parameters were calculated in the energy range of 0.015-15 MeV using the FLUKA algorithm. In addition, EBF, EABF, and ΣR values were also determined for the prepared glasses. These values indicated that the parameters for shielding (MAC, HVL, Zeff, EBF, EABF, and ΣR) are dependent upon the Samarium (III) oxide content. Furthermore, the addition of Samarium (III) oxide to the examined glass samples greatly reinforced their shielding capacity against gamma photon. The findings of the current study were compared to analyses of the XCOM software, some concretes, and lead. In the experiment, it was found that the SMG0.6 glass sample was the strongest shield.

Specific Absorption Rate Dependency on the Co2+ Distribution and Magnetic Properties in CoxMn1-xFe2O4 Nanoparticles.

Mixed ferrite nanoparticles with compositions CoxMn1-xFe2O4 (x = 0, 0.2, 0.4, 0.6, 0.8, and 1.0) were synthesized by a simple chemical co-precipitation method. The structure and morphology of the nanoparticles were obtained by X-ray diffraction (XRD), transmission electron microscope (TEM), Raman spectroscopy, and Mössbauer spectroscopy. The average crystallite sizes decreased with increasing x, starting with 34.9 ± 0.6 nm for MnFe2O4 (x = 0) and ending with 15.0 ± 0.3 nm for CoFe2O4 (x = 1.0). TEM images show an edge morphology with the majority of the particles having cubic geometry and wide size distributions. The mixed ferrite and CoFe2O4 nanoparticles have an inverse spinel structure indicated by the splitting of A1g peak at around 620 cm-1 in Raman spectra. The intensity ratios of the A1g(1) and A1g(2) peaks indicate significant redistribution of Co2+ and Fe3+ cations among tetrahedral and octahedral sites in the mixed ferrite nanoparticles. Magnetic hysterics loops show that all the particles possess significant remnant magnetization and coercivity at room temperature. The mass-normalized saturation magnetization is highest for the composition with x = 0.8 (67.63 emu/g), while CoFe2O4 has a value of 65.19 emu/g. The nanoparticles were PEG (poly ethylene glycol) coated and examined for the magneto thermic heating ability using alternating magnetic field. Heating profiles with frequencies of 333.45, 349.20, 390.15, 491.10, 634.45, and 765.95 kHz and 200, 250, 300, and 350 G field amplitudes were obtained. The composition with x = 0.2 (Co0.2Mn0.8Fe2O4) with saturation magnetization 57.41 emu/g shows the highest specific absorption rate (SAR) value of 190.61 W/g for 10 mg/mL water dispersions at a frequency of 765.95 kHz and 350 G field strength. The SAR values for the mixed ferrite and CoFe2O4 nanoparticles increase with increasing concentration of particle dispersions, whereas for MnFe2O4, nanoparticles decrease with increasing the concentration of particle dispersions. SARs obtained for Co0.2Mn0.8Fe2O4 and CoFe2O4 nanoparticles fixed in agar ferrogel dispersions at frequency of 765.95 kHz and 350 G field strength are 140.35 and 67.60 W/g, respectively. This study shows the importance of optimizing the occupancy of Co2+ among tetrahedral and octahedral sites of the spinel system, concentration of the magnetic nanoparticle dispersions, and viscosity of the surrounding medium on the magnetic properties and heating efficiencies.

In-Silico Monte Carlo Simulation Trials for Investigation of V2O5 Reinforcement Effect on Ternary Zinc Borate Glasses: Nuclear Radiation Shielding Dynamics.

In the current study, promising glass composites based on vanadium pentoxide (V2O5)-doped zinc borate (ZnB) were investigated in terms of their nuclear-radiation-shielding dynamics. The mass and linear attenuation coefficient, half-value layer, mean free path, tenth-value layer, effective atomic number, exposure-buildup factor, and energy-absorption-buildup factor were deeply simulated by using MCNPX code, Phy-X PSD code, and WinXcom to study the validation of ZBV1, ZBV2, ZBV3, and ZBV4 based on (100-x)(0.6ZnO-0.4B2O3)(x)(V2O5) (x = 1, 2, 3, 4 mol%) samples against ionizing radiation. The results showed that attenuation competencies of the studied glasses slightly changed while increasing the V2O5 content from 1 mol% to 4 mol%. The domination of ZnO concentration in the composition compared to B2O3 makes ZnO substitution with V2O5 more dominant, leading to a decrease in density. Since density has a significant role in the attenuation of gamma rays, a negative effect was observed. It can be concluded that the aforementioned substitution can negatively affect the shielding competencies of studied glasses.