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Based on the experimental and theoretical radiation attenuation, this study produced and tested a composite material made of polyester reinforced with SnO at varied concentrations and abbreviated as Pol-SnOx, where x = 0–60% with steps of 20 wt% Also, the polyester samples were doped with SnO of different particle sizes: Micro, Nano, and 50% Micro/50% Nano mix to investigate the effect of the particle size on the radiation attenuation performance. In the photon energy range of 0.015–15 MeV, their radiation shielding properties were empirically determined using an HPGe detector and theoretically determined using Phy-X/PSD software. The linear attenuation coefficient (LAC) values dropped from 1.361 to 0.022 cm−1 for Pol-SnO0, from 13.611 to 0.033 cm−1 for Pol-SnO20, from 31.700 to 0.049 cm−1 for Pol-SnO40, and from 61.076 to 0.076 cm−1 for Pol-SnO60 in the photon energy (Eγ) range from 0.015 to 15 MeV. The LAC values of the fabricated Pol-SnOx samples increased as the SnO concentrations increased. Also, the addition of 50% Micro/50% Nano mix particle size of the SnO to the polyester significantly increased the values of the LAC. The percentages of LAC improvement of SnO nano-particles were 16.625%, 13.236%, 8.714%, and 7.935% at the Eγ values of 0.059, 0.661, 1.173, and 1.332 MeV, respectively. Also, the LAC values were enhanced by adding SnO containing 50% Micro/50% Nano mix particles by 19.097%, 15.271%, 9.854%, and 9.071% at the Eγ values of 0.059, 0.661, 1.173, and 1.332 MeV, respectively, when compared to microparticles. The addition of 50% Micro/50% Nano Mix of SnO with 60% content to the polyester showed the highest LAC and radiation protection efficiency and lowest half-value layer and transmission factor among the other samples due to increased SnO doping and interparticle distances of the Micro and Nano mix.

Radiation and nuclear technologies have side effects in addition to their important applications, so appropriate shields must be used to protect users and the public from high doses as a result of exposure to this radiation. In this work, the attenuation coefficients for polyester composites doped with waste iron filings (IFs) were studied. Six samples of different IF concentrations were manufactured, namely, Poly, Poly-IF20, Poly-IF30, Poly-IF40, Poly-IF50, and Poly-IF60 (where Poly-IF60 represents 40% polyester and 60% IF). We measured the attenuation factors using high purity germanium (HPGe)-detector along with three radioactive sources 241Am (emitting energy of 0.06 MeV), 137Cs (emitting energy of 0.662 MeV), and Co-60 (emitting energy of 1.173 and 1.333 MeV). We compared the linear attenuation coefficient (LAC) obtained by theoretical (i.e., XCOM software) and experimental (i.e., HPGe-detector) approaches for the prepared polyester composites at various photon energies (0.060, 0.662, 1.173, and 1.333 MeV). The greatest difference between the LAC values of the samples occurs at 0.060 MeV, where the Poly-IF60 sample has a much greater LAC than the other shields, followed by the Poly-IF50 sample, Poly-IF40 sample, and so on until the pure polyester shield. Specifically, their values are equal to 0.245, 0.622, 0.873, 1.187, 1.591, and 2.129 cm−1 for Poly, Poly-IF20, Poly-IF30, Poly-IF40, Poly-IF50, and Poly-IF60, respectively. We calculated the transmission factor (TF) and the radiation shielding efficiency (RSE), and found that the TF for Poly-IF30 is equal to 28.82%, 77.94%, 82.75%, and 83.75% at 0.060, 0.662, 1.173, and 1.333, respectively, while its RSE is equal to 82.57%, 24.00%, 18.80%, and 17.72%, respectively. The fast neutron removal cross-section (FNRC) of the polyester samples was calculated and the values increase when more Ifs are added to the samples. More specifically, the FNRC values are equal to 0.095, 0.100, 0.103, 0.107, 0.110, and 0.113 cm−1 for Poly, Poly-IF20, Poly-IF30, Poly-IF40, Poly-IF50, and Poly-IF60, respectively.

In an attempt to reutilize marble waste, a new approach is presented in the current study to promote its use in the field of shielding against ionizing radiation. In this study, we aimed to develop a novel and sustainable/eco-friendly lead-free radiation shielding material by improving artificial marble (AM) produced from marble waste combined with polyester by reinforcing it with bismuth oxide (Bi2O3) nanoparticles. Six samples of AM samples doped with different concentrations ( 0 % ,   5 % ,   10 % ,   15 % , 20 % , and 25 % ) of Bi2O3 nanoparticles were prepared. The linear attenuation coefficient ( L A C ) values were measured experimentally through the narrow beam method at different energies (0.0595   M e V , 0.6617   M e V , 1.1730   M e V , and 1.330   M e V ) for all samples with various concentrations of Bi2O3. Radiological shielding parameters such as half value layer ( H V L ), tenth-value layer ( T V L ), and radiation shielding efficiency ( R S E ) were estimated and compared for all the different samples. The results prove that increasing the concentration of Bi2O3 leads to the enhancement of the radiation shielding properties of the AM as a shielding material. It was observed that as the energy increases, the efficiency of the samples falls. High energy dependence was found when calculating the H V L and T V L values of the samples, which increased with increases in the energy of the incident photons. A comparison between the sample with the most efficient gamma radiation attenuation capability (AM- 25 % ), concrete, and lead was conducted, and a discussion regarding their radiation shielding properties is presented herein. The results show that the AM- 25 % sample is superior to the ordinary concrete over all the studied energy ranges, as evidenced by its significantly lower H V L s . On the contrary, lead is superior to the AM- 25 % sample over all the studied energy ranges owing to its unbeatable density as a shielding material. Overall, this new type of artificial marble has the potential to be used as a radiation shielding material at low- to medium-gamma energy regions, specifically in medical imaging and radiation therapy. [ABSTRACT FROM AUTHOR]

Five glass samples with the following chemical formation: 21.5 SiO2-58.5B2O3-(20-x) ZnO- xLa2O3, where x = 0–10 mol% were fabricated utilizing melt quenching. With an increase in La2O3, the glasses' density increased from 3.174 to 4.754 g/cm3. Experimental data were used to evaluate the mechanical characteristics, and the Makishima and Mackenzie model's semi-empirical methods were used to analyze the elastic properties. As the amount of La2O3 increases, there's a noticeable rise in the velocity of ultrasonic waves. This heightened velocity is likely linked to the strengthening or increased rigidity of the glass network. Elastic moduli values of the glasses under investigation increase with an increase La2O3 content. Employing Phy-X/PSD code, the radiation attenuation behaviour of zinc borosilicate glasses with varying La2O3 concentrations were examined. With increased energy, the enhancement LAC decreases from 2.576 to 0.0375. The ZBSL10 glasses demonstrated strong mechanical and physical characteristics as well as radiation shielding capabilities. The features of the ZBSL glasses are particularly attractive for a variety of mechanical and shielding applications. [ABSTRACT FROM AUTHOR]

The composition of the pentagonal glass system, which is composed of 57B2O3-16SiO2-11BeO- (16-x) MgO-xLa2O3, x = (0 ≤ x ≤ 16 mol %), has been synthesized by the melt quench process. XRD diffractograms' wide haloes testified to the materials' amorphous state. It was discovered that, density increased in response to La2O3 concentration, whereas molar volume decreased. Additionally, the ranges of longitudinal and shear velocities are 4730 to 5085 m/s and 2685–2895 m/s, respectively. The elastic moduli for longitudinal range between 71.9–154.3 GPa, shear range between 23.2–50 GPa, bulk range between 23.2–50 GPa, and Young's range between 58.5–126 GPa, respectively. The study employed Phy-X/PSD code to examine the radiation attenuation behaviour of magnesium beryllia-borosilicate, also known as (BMBSLa) glasses, at varying concentrations of La2O3. We examined the relationship among the half value layer (HVL) and density. HVL values at a density of 3.213 g/cm3 range from 0.0087 to 11.746 cm and at density of 5.967 g/cm3 range from 0.02 to 5.727 cm at (0.015–15 MeV). Tenth value layer (TVL) and mean free path (MFP) are evaluation and comparison between HVL, TVL and MFP for the same glass at specific energy were also conducted. The glass samples under investigation are excellent candidates for usage in the field of shielding radiation because they are more transparent. [ABSTRACT FROM AUTHOR]

This study aims to investigate the impact of CeO2 content and particle size on the radiation shielding abilities of polydimethylsiloxane, also known as silicon rubber (SR). We prepared different SR samples with 10, 30, and 50% of micro and nano CeO2 and we measured the linear attenuation coefficient (LAC) for these samples. We found that the LAC of the SR increases by increasing the CeO2 and all prepared SR samples had higher LACs than the pure SR. We examined the effect of the size of the particles on the LAC and the results demonstrated that the LAC for nano CeO2 is higher than that of micro CeO2. We investigated the half value layer (HVL) for the prepared SR samples and the results revealed that the SR with 10% micro CeO2 had a greater HVL than the SR with 10% nano CeO2. The HVL results demonstrated that the SR containing nanoparticles had higher attenuation effectiveness than the SR with micro CeO2. We also prepared SR samples containing CeO2 in both sizes (i.e., micro and nano) and we found that the HVL of the SR containing both sizes was lower than the HVL of the SR with nano CeO2. The radiation protection efficiency (RPE) at 0.059 MeV for the SR with 10% micro and nano CeO2 was 94.2 and 95.6%, respectively, while the RPE of SR containing both sizes (5% micro CeO2 + 5% micro CeO2) was 96.1% at the same energy. The RPE results also indicated that the attenuation ability was improved when utilizing the micro and nano CeO2 as opposed to the micro CeO2 or nano CeO2 at 0.662, 1.173, and 1.333 MeV. [ABSTRACT FROM AUTHOR]

We developed new composites for photons shielding applications. The composite were prepared with epoxy resin, red clay and bismuth oxide nanoparticles (Bi2O3 NPs). In order to establish which ratio of red clay to Bi2O3 NPs provides the best shielding capabilities, several different ratios of red clay to Bi2O3 NPs were tested. The transmission factor (TF) was calculated for two different thicknesses of each sample. From the TF data, we found that epoxy resin materials have a high attenuation capacity at low energy. For ERB-10 sample (40%Epoxy + 50% Red clay + 10% Bi2O3 NPs), the TF values are 52.3% and 14.3% for thicknesses of 0.5 and 1.5 cm (at 0.06 MeV). The composite which contains the maximum amount of Bi2O3 nanoparticles (40%Epoxy + 50% Red clay + 10% Bi2O3 NPs, coded as ERB-30) has lower TF than the other composites. The TF data demonstrated that ERB-30 is capable of producing more effective attenuation from gamma rays. We also determined the linear attenuation coefficient (LAC) for the prepared composites and we found that the LAC increases for a given energy in proportion to the Bi2O3 NPs ratio. For the ERB-0 (free Bi2O3 NPs), the LAC at 0.662 MeV is 0.143 cm−1, and it increases to 0.805 cm−1 when 10% of Bi2O3 NPs is added to the epoxy resin composite. The half value layer (HVL) results showed that the thickness necessary to shield that photons to its half intensity can be significantly lowered by increasing the weight fraction of the Bi2O3 NPs in the epoxy resin composite from 0 to 30%. The HVL for ERB-20 and ERB-30 were compared with other materials such as (Epoxy as a matrix material and Al2O3, Fe2O3, MgO and ZrO2 as filler oxides in the matrix at 0.662 MeV. The HVL values for ERB-20 and ERB-30 are 4.385 and 3.988 cm and this is lower than all the selected epoxy polymers. [ABSTRACT FROM AUTHOR]

Background: Cardiovascular magnetic resonance (CMR) imaging is an important modality that allows the assessment of regional myocardial function by measuring myocardial deformation parameters, such as strain and strain rate throughout the cardiac cycle. Feature tracking is a promising quantitative post-processing technique that is increasingly used. It is commonly applied to cine images, in particular steady-state free precession, acquired during routine CMR examinations. Objective: To review the studies that have used feature tracking techniques in healthy subjects or patients with cardiovascular diseases. The article emphasizes the advantages and limitations of feature tracking when applied to regional deformation parameters. The challenges of applying the techniques in clinics and potential solutions are also reviewed. Results: Research studies in healthy volunteers and/or patients either applied CMR-feature tracking alone to assess myocardial motion or compared it with either established CMR-tagging techniques or to speckle tracking echocardiography. These studies assessed the feasibility and reliability of calculating or determining global and regional myocardial deformation strain parameters. Regional deformation parameters are reviewed and compared. Better reproducibility for global deformation was observed compared with segmental parameters. Overall, studies demonstrated that circumferential was the most reproducible deformation parameter, usually followed by longitudinal strain; in contrast, radial strain showed high variability. Conclusion: Although feature tracking is a promising tool, there are still discrepancies in the results obtained using different software packages. This highlights a clear need for standardization of MRI acquisition parameters and feature tracking analysis methodologies. Validation, including physical and numerical phantoms, is still required to facilitate the use of feature tracking in routine clinical practice. [ABSTRACT FROM AUTHOR]