The aim of the current study is to investigate the impact of introducing micro- and nanoparticle MgO as a filler into epoxy resin on the radiation shielding abilities of the prepared samples. To this end, we performed a gamma-radiation spectroscopy experiment with the help of an HPGe detector and Am-241, Cs-137, and Co-60 sources. We evaluated the particle size effect (PSE) and detected the maximum PSE value with the addition of 50 wt% MgO particles, indicating that nanoparticle MgO was more successful in shielding against incoming radiation than microparticle MgO. We compared the half-value layer (HVL) for the samples with 10 wt%, 20 wt%, and 30 wt % micro-MgO and nano-MgO and found that the HVL values were lower for the nanoparticle samples than for the microparticles samples, confirming that smaller particle sizes enhanced the shielding ability of the samples against radiation. The MFP results showed that epoxy matrices containing micro-MgO, for all investigated energies, resulted in higher MFP values that those containing nano-MgO.

We have attempted to develop the gamma radiation shielding abilities of newly prepared epoxy composites by introducing ZrO₂. The radiation shielding parameters are experimentally reported below. The experimental setup included an HPGe detector and different radioactive point sources which emitted photons with energies of 0.06, 0.662, 1.173, and 1.333 MeV. The gamma radiation shielding abilities of the epoxy composites were examined in the context of the linear attenuation coefficient (LAC), half-value layer (HVL), radiation absorption ratio, and other factors. The experimental and Phy-X results for the LAC were compared, and acceptable consistency was reported. The lowest LAC values were reported for EBZr-0 (free of ZrO₂), and we found that the photon attenuation competence of the present epoxy improved as a result of increasing the ZrO₂ content. We compared the LAC values for the present epoxy composites with other samples, and we found that the prepared composites with 20% to 40% ZrO₂ had higher LAC values than epoxy with 30% Yahyali Stone. The HVL lengths of the epoxy composites reduced with the addition of ZrO₂ for the four selected energies, which confirmed that introducing ZrO₂ improves the radiation absorption abilities of epoxy composites. At 0.06 MeV, the HVL for the ZrO₂-free epoxy was 2.60 cm, which fell to 0.23 cm after adding 40% ZrO₂. The mean free path (MFP) for the prepared composites was less than 1 cm at 0.06 MeV (standard for EBZr-0), while it was 1.32 cm for EBZr-10. For the other energies, it was higher than 6 cm, and became higher than 10 cm at 1.333 MeV for all composites. The obtained results suggest that non-toxic, natural, and cheap epoxy composites with high ZrO₂ content have the potential to improve the gamma ray shielding competence of epoxy composites for low energy radiation applications.

The current study aims to investigate the radiation shielding properties of mortar samples with Fe₂O₃ nanoparticles for radiation protection applications. For the reference mortar (free Fe₂O₃ nanoparticles) and the mortar with different concentrations of Fe₂O₃ nanoparticles, we experimentally measured the transmission factor (I/I0) for four different thicknesses of the prepared mortar. The I/I₀ results indicated that the transmission of the photons through the mortars decreases with increases in the mortar’s thickness. The lowest TF was found for the mortar coded as MI-25 (contains 25 wt.% of Fe₂O₃ nanoparticles), which gives an indication about the development in the attenuation ability of the prepared mortar samples due to the addition of Fe₂O₃. Similarly, the linear attenuation coefficient (LAC) results showed an increasing trend with the addition of Fe₂O₃ nanoparticles for the four tested energies. These results confirm that increasing the ratio of Fe₂O₃ nanoparticles can lead to a remarkable improvement in the gamma ray shielding. We reported the half value layer (HVL) and we found that the HVL for the reference mortar at 0.06 MeV is 1.223 cm, while it changed from 1.19 to 1.074 cm for the mortar with 5 and 25 wt.% of Fe₂O₃ nanoparticles. The HVL results demonstrated that increasing the ratio of Fe₂O₃ nanoparticles can lead to a notable reduction in the HVL. The tenth value layer results proved that we can develop new mortars for radiation shielding applications by introducing more concentrations of Fe₂O₃ nanoparticles.

In this research, polymers were fabricated through combining polyester, boron oxide (B₂O₃), and Tellurium oxide (TeO₂). B₂O₃ has good neutron absorption and TeO₂ is not only highly dense (5.670 g/cm³) but also environment-friendly, compared to PbO, as well as being a good photon absorber. The radiation protection features for five investigated samples were examined utilizing an HPGe detector and point sources Am-241, Cs-137, and Co-60. The accuracy of the experimental setup of this experiment was proven through the linear attenuation coefficient (LAC) values obtained from the theoretical (XCOM) and experimental (HPGe) values of the newly developed polymers. The attained results showed that the values of LAC decrease with increasing energy. Moreover, at low energy, a noteworthy increase was found for the LAC values with the addition of TeO₂. Due to the increase in TeO₂ content of the polymers, the value of the half value layer (HVL) decreases from 6.073–4.193 cm at energy 0.662 MeV, from 7.973–5.668 cm at energy 1.173 MeV, and 8.514–6.061 cm at energy 1.333 MeV. The values of the effective atomic number (Z_eff) showed an improvement with the increase in TeO₂ content in the polymers. For example, at energy 0.150 MeV, the Z_eff values of the prepared sample followed this decreasing trend - PBT-40 > PBT-30 > PBT-20 > PBT-10 > PBT-0.

The compound BiFe_0.7Mn_0.3O₃ consisting at room temperature of coexistent anti-polar orthorhombic and polar rhombohedral phases has a metastable structural state, which has been studied by laboratory X-ray, synchrotron and neutron diffraction, magnetometry, differential thermal analysis, and differential scanning calorimetry. Thermal annealing of the sample at temperatures above the temperature-driven phase transition into the single phase rhombohedral structure (~700 K) causes an increase of the volume fraction of the rhombohedral phase at room temperature from ~10% up to ~30%, which is accompanied by the modification of the magnetic state, leading to strengthening of a ferromagnetic component. A strong external magnetic field (~5 T) applied to the sample notably changes its magnetic properties, as well as provides a reinforcement of the ferromagnetic component, thus leading to an interaction between two magnetic subsystems formed by the antiferromagnetic matrix with non-collinear alignment of magnetic moments and the nanoscale ferromagnetic clusters coexisting within it. The modification of the structural state and magnetic properties of the compounds and a correlation between different structural and magnetic phases are discussed focusing on the effect of thermal annealing and the impact of an external magnetic field.