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With the use of multilayer materials such as concrete, mortar and ceramics that were fortified with PbO, WO3 and Bi2O3 nanoparticles, our study's objective was to produce a an effective photon shielding system. Experimental evaluation of the radiation shielding efficiency of two sets of samples with various thicknesses was conducted. The elemental content and morphology of the samples were corroborated by SEM and EDX studies, with ceramic samples exhibiting superior particle distribution and fewer voids than concrete and mortar specimens. The linear attenuation coefficient (LAC) was studied both experimentally and numerically using the Phy-X program, and it was found that the two sets of values were in satisfactory agreement. The values of LAC were consistently greater for samples with 30% of the selected heavy metal oxides than for those with 10%. The LAC for Cer-1 was 5.003 cm−1 at 0.059 MeV, whereas the corresponding LAC for Cer-2 was 2.123 cm−1. The LAC values were as follows: ceramics (5.003 cm−1), mortar (2.999 cm−1), concrete (2.733 cm−1), and the transmission factor (TF) examination of the multiple-layer specimens showed that the TF of the 3 cm thick multilayer sample was lower than that of the 2 cm thick sample and that both multilayer samples displayed better attenuation efficiency in comparison to single-layer specimens. The results show the possibility for employing multilayer structures with different densities, thicknesses, and sizes in suitable radiation shielding applications. [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]

The current work discusses the radiation attenuation capability and different shielding characteristics of different mortar samples. The samples were prepared by replacing different percentages of fine aggregate with iron filling and replacing different percentages of hydrated lime with Bi2O3 (0–50 wt.%). The prepared mortar samples are coded as CHBFX where X = 0, 10, 30, and 50 wt.%. The mass and linear attenuation coefficient was determined experimentally using a narrow beam technique, where a high purity germanium detector, and different point gamma-ray sources (such as Am-241, Cs-137, and Co-60). The linear attenuation coefficient was also calculated using the Monte-Carlo simulation code and the online Phy-X/PSD software. The comparison of the three methods showed a good agreement in the results. The linear attenuation coefficient drops from 19.821 to 0.053 cm−1 for CHBF0, from 27.496 to 0.057 cm−1 for CHBF10, from 42.351 to 0.064 cm−1 for CHBF30, and from 55.068 to 0.071 cm−1 for CHBF50 at photon energy range from 0.015 to 15 MeV. The half-value layer thickness, tenth-value layer thickness, and mean free path of the prepared mortar composites were also calculated photon energy ranged from 0.015 to 15 MeV. The fast neutron removal cross-section of the prepared CHBFX mortar samples have values of 0.096 cm−1, 0.098 cm−1, 0.103 cm−1, and 0.107 cm−1 for the mortar samples CHBF0, CHBF10, CHBF30, and CHBF50, respectively. The results showed that the mortar sample with the highest iron filing concentration, CHBF50, provides the best protection against gamma rays and fast neutrons which could be used in the nuclear and medical fields. [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]

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]

A host glass matrix composed of potassium bismuth borosilicate that has been reinforced with 2, 4, 8, and 16 mol% La 2 O 3 to act as a gamma-ray shield. Thermal, optical, and shielding qualities have been impacted by the penetration of La 2 O 3 into the suggested host glass, which fills the interstitial spaces. The density increases from 4.304 g/cm3 to 6.384 g/cm3 with an increase in La 2 O 3 while (V m) decrease. The glass under consideration demonstrated a high degree of thermal stability as the content of La 2 O 3 increased. When La3+ ions are added, the resulting glasses' optical transparency improves to above 77 %. The origin of these glasses is non-metallic. Gamma-ray attenuation of the glasses was developed with increasing amounts of La 2 O 3. The glass containing 16 mol% La 2 O 3 is a promising candidate for protective shields in various nuclear applications due to its high thermal stability, transparency, and effective capability to reduce gamma rays. • Potassium bismuth borosilicate glasses containing La 2 O 3 that were manufactured. • The density increases from 4.304 g/cm3 to 6.384 g/cm3 V m). • The glass containing 16 mol% La 2 O 3 is a promising candidate for protective shields. [ABSTRACT FROM AUTHOR]

The purpose of this work is to study the thermal, optical, structural, and radiation-shielding features of glass system with composition 57B 2 O 3 –16SiO 2 –11BeO- (16-x) MgO- x La 2 O 3 , x = (0 ≤ x ≥ 16). The structural characteristics of glass samples are examined using XRD. This glass's molar volume decreased from 18.21 to 17.46 (cm³/mol), while its density increased from 3.213 to 5.967 g/cm³. Differential thermal analysis data were used to assess the thermal stability (ΔT) for BSLa samples. It was discovered that when the La 2 O 3 amount increased, the glass stability increased. The optical band gap (E o p t d i ) , (E o p t i n d i ) and Urbach's energy (E u) were computed using UV absorption spectra. (E o p t d i ) decrease from 4.323 to 3.816 eV and (E o p t i n d i ) decrease from 3.413 to 2.95 eV, whereas (E u) increase from 0.278 to 0.324 as a result of the changes of borosilicate's structured caused by the addition of La 2 O 3. The examined glasses may be utilized for non-linear optical applications, according to the high (n) and low metallization (M) values. The Phy-X tool was utilized to obtain (MAC), (LAC), and (Z eff) of the suggested glasses within the energies 0.015–15 MeV. The BSLa 16 sample achieved the highest values of the (MAC), (LAC), and (Z eff). Consequently, BSLa 16 is a good option for gamma-ray shielding applications. Skin depth (δ) of BSLa glasses. [Display omitted] • The ′ 57B 2 O 3 –16SiO 2 –11BeO- (16-x) MgO- x La 2 O 3 , x = 0, 2, 4, 8, and 16 mol %), glasses were prepared. • ′.Density increased from 3.213 to 5.967 g/cm³. • ′The glass stability increased. • ′ BSLa 16 is a good option for gamma-ray shielding applications. [ABSTRACT FROM AUTHOR]

Glasses with the composition 48B 2 O 3 – 13SiO 2 – 7BaO- (32-x) Na 2 O-xY 2 O 3 , (x = 0, 1, 2, 4, and 8 mol %) were synthesized by the melt quenching procedure. There is good transparency in every glass sample. The increase in density (2.825–3.894 gm/cm3) of the present glasses is what triggered the decline in molar volume (25.41–21.80 cm3/mol) and the decrease in the Boron–Boron distance (0.475–0.452 nm). The estimated values show that E opt. indi. & E opt. di are 2.317, 2.672, 2.8, 2.98 and 3.1 eV, 2.69, 2.92, 3.05, 3.25, and 3.44 eV respectively, whereas (E u ) values declined. As the Y 2 O 3 increased the refractive index (n D) increased. (n D) of the synthesized glasses using E opt. indi. & E opt. di were estimated. To find the radiation properties of the suggested glasses, the Phy-X/PSD code was employed. We concluded that the current glasses have better radiation shielding capabilities when employed in such fields. As the Y 2 O 3 replacing ratio increased ∑ R increased. • The glass system 48B 2 O 3 – 13SiO 2 – 7BaO- (32-x) Na 2 O-xY 2 O 3 , x = (0 ≤ x ≥8) in mol% was prepared. • The density increased from 2.825 to 3.894 g/cm3. • As the Y 2 O 3 replacement ratio increased the refractive increased. • The glass sample G5 exhibited the best properties. [ABSTRACT FROM AUTHOR]

W3+-doped multicomponent B 2 O 3 -SiO 2 -ZnO-Na 2 O glasses in a range of concentrations (0–6 mol %) have been manufactured using the melt quenching method. The result of replacing Na 2 O with WO 3 on the structure of zinc borosilicate glasses was examined using XRD. The density of the glass system has been determined using Archimedes' method. The substitution of Na 2 O with WO 3 in the glass composition would result in increased density and a decrease in molar volume. The incorporated WO 3 longitudinal velocities (V L m/s) increased from 4775 to 5120 and shear velocities (V S) increased from 2735 to 2955. The elastic moduli resulted in a uniform behavior when WO 3 increased, and the values ranged from 72.6 to 121.1 GPa for longitudinal modulus, 23.8–40.3 GPa for shear modulus, 40.8–67.3 GPa for bulk modulus, and 59.8–100.9 GPa for Young's modulus. The Debye temperature (θ D) increases from 431.71 to 506.33 as an increase in WO 3. Higher (θ D) indicates stronger atomic bonds and stiffer glasses. The elastic moduli based on the Makishima-Mackenzie model have been investigated. The trend indicates an increase in (Lth) varied between 137.7 and 219.1 GPa, (Gth) ranged from 38.7 to 50.3 GPa, (K) ranged from 86.16 to 152 GPa, and (Y) varied between 95.6 and 128.8 GPa, with an increase in the concentration of WO 3. The Phy-X program was used to determine the shielding characteristics for the samples, including mean free range (MFP), effective atomic number (Z eff), and neutron. Z eff increases along with WO 3 concentration and MFP decreases. The increase in the (FNRCS) due to the rise in sample density is linked to the concentration of WO 3. FNRCS (cm−1) values are 0.123 for SW 0 , 0.128 for SW 1 , 0.137 for SW 2 , 0.143 for SW 4 , and 0.162 for SW 6. It was determined that SW 6 had the best shielding capacity based on the MFP and Z eff values. This could have promising implications for various applications where radiation shielding or protection is necessary. This suggests that these glasses offer superior features that make them effective for shielding. • 21SiO 2 -13ZnO-(17-x) Na 2 O-xWO 3 (0 ≤ x ≤ 6 mol %), glasses were manufactured. • Density increases along with their WO 3 concentration. • Longitudinal velocities (V L) and shear velocities (V S) are increased. • It was determined that SW 6 had the best shielding capacity. [ABSTRACT FROM AUTHOR]