Structural and Magnetic Phase Transitions in BiFe1−x_{1−x}Mnx_xO3_3 Solid Solution Driven by Temperature

The crystal structure and magnetic state of the (1 − x)BiFeO$_3$-(x)BiMnO$_3$ solid solution has been analyzed by X-ray diffraction using lab-based and synchrotron radiation facilities, magnetization measurements, differential thermal analysis, and differential scanning calorimetry. Dopant concentration increases lead to the room-temperature structural transitions from the polar-active rhombohedral phase to the antipolar orthorhombic phase, and then to the monoclinic phase accompanied by the formation of two-phase regions consisting of the adjacent structural phases in the concentration ranges 0.25 < x$_1$ < 0.30 and 0.50 ≤ x$_2$ < 0.65, respectively. The accompanied changes in the magnetic structure refer to the magnetic transitions from the modulated antiferromagnetic structure to the non-colinear antiferromagnetic structure, and then to the orbitally ordered ferromagnetic structure. The compounds with a two-phase structural state at room temperature are characterized by irreversible temperature-driven structural transitions, which favor the stabilization of high-temperature structural phases. The magnetic structure of the compounds also exhibits an irreversible temperature-induced transition, resulting in an increase of the contribution from the magnetic phase associated with the high-temperature structural phase. The relationship between the structural parameters and the magnetic state of the compounds with a metastable structure is studied and discussed depending on the chemical composition and heating prehistory

Influence of WO3 content on gamma rays attenuation characteristics of phosphate glasses at low energy range

The radiation attenuation characteristics of WO3-Li2O-ZnO-P2O5 glasses have been examined using Phy-X software. The linear attenuation coefficient is correspondingly increased with the inclusion of WO3, which indicates the existence of a reducing tendency in the photon transmission correlating with an increment in the WO3 content in the glasses. When density is increased, there is a considerable reduction in the half-value layer (HVL), which is most noticeable between 80 and 100 keV. Because the HVL reaches high values at 100 keV for the samples, it can be deduced that the HVL steadily increases as the energy increases. Additionally, increasing the amount of WO3 in the glasses causes the mean free path (MFP) to decrease. The MFP for the glasses was compared with that of different heavy concretes, and the comparison demonstrated that the chosen systems have the potential to be used for the fabrication of protection masks that are utilized during diagnostic radiation treatment. We determined the ratio between the tenth value layer for the free-WO3 sample and the sample with 10 mol% and we found that the ratio is higher than 1, which suggests that the tenth value layer is decreased with the addition of WO3 to the glasses

Influence of ZnF₂ and WO₃ on Radiation Attenuation Features of Oxyfluoride Tellurite WO₃-ZnF₂-TeO₂ Glasses Using Phy-X/PSD Software

The radiation shielding features of the ternary oxyfluoride tellurite glasses were studied by calculating different shielding factors. The effect of the TeO2, WO3, and ZnF2 on the tested glass system’s attenuating performance was predicted from the examination. The mass attenuation coefficient (µ/ρ) values for the oxyfluoride tellurite glasses depend highly on the concentration of WO3, as well as ZnF2. All the present ZnFWTe1-ZnFWTe5 samples have higher µ/ρ values than that of the pure TeO2 glass at all energies. For the samples with a fixed content of WO3, the replacement of TeO2 by ZnF2 increases the µ/ρ, while for the glasses with a fixed content of TeO2, the replacement of WO3 by ZnF2 results in a decline in the µ/ρ values. The results revealed that ZnFWTe4 has the lowest linear attenuation coefficient (µ) among the oxyfluoride tellurite glasses, whereby it has a slightly higher value than pure TeO2 glass. The maximum effective atomic number (Zeff) is found at 0.284 MeV and varied between 31.75 and 34.30 for the tested glasses; it equaled to 30.29 for the pure TeO2 glass. The half-value layer (HVL) of the glasses showed a gradual decline with increasing density. The pure TeO2 was revealed to have thicker HVL than the selected oxyfluoride tellurite glasses. A 1.901-cm thickness of the sample, ZnFWTe1, is required to decrease the intensity of a photon with an energy of 0.284 MeV to one-tenth of its original, whereas 1.936, 1.956, 2.212, and 2.079 cm are required for glasses ZnFWTe2, ZnFWTe3, ZnFWTe4, and ZnFWTe5, respectively

Effect of Gamma Irradiation on the Structural, Optical, Electrical, and Ferroelectric Characterizations of Bismuth-Modified Barium Titanate Ceramics

Materials with ferroelectric properties, low bandgap energies, high polarization, low loss, and thermal stability are essential for future solar-cell applications. Researchers have attempted to obtain such materials by using several approaches. In this vein, a novel approach is reported in this work using gamma ray irradiation. The effect of gamma radiation on the structural, optical, and ferroelectric characterizations of bismuth (Bi)-doped barium titanate (BaTiO3 (BT)), namely Ba0.95Bi0.05TiO3 ceramics (abbreviated as (Bi:BT)), was investigated. X-ray diffraction, structure refinement, and Raman study revealed the presence of a perovskite structure with a tetragonal phase in all investigated samples. Morphological study revealed a nonuniform grain size and some porosity. Gamma irradiation-induced combined effects were proved by a detailed analysis of bond lengths, bond angles, octahedral distortions, oxygen vacancies, and charge compensations. Electron paramagnetic resonance (EPR) study gave direct evidence of oxygen vacancies in the irradiated samples. After gamma irradiation, UV–vis study indicated a decrease in the bandgap from 3.14 to 2.80 eV and a significant increase in visible light absorption. Cole–Cole plots confirm as an increase in gamma-ray dose results in higher levels of electron hopping. Study of the P–E hysteresis loop demonstrated that ferroelectric properties could be maintained after gamma irradiation, with a slight decrease in remnant polarization. The behaviour of the P–E was correlated with increasing gamma dose in the investigated ceramics, demonstrating a strong gamma dependence in the loops’ profile. We guess that the present approach may be a promising technique for enhancing the multifunctionality of electronic devices

The affinity of bentonite and WO3 nanoparticles toward epoxy resin polymer for radiation shielding

A thorough comparative analysis was conducted between pure epoxy and a novel epoxy composite that included bentonite and WO3 nanoparticles in varying ratios. This study examined five distinct novel epoxy samples (E00, EB0, EBW1, EBW2, and EBW3) to assess their radiation shielding efficiency (RSE), taking into account the addition of bentonite and WO3 nanoparticles. Furthermore, the study compared the RSE of pure epoxy with that of the novel epoxy composite. To evaluate the radiation shielding ability of the studied epoxy samples, a few radiation shielding parameters such as linear attenuation coefficient (LAC), mass attenuation coefficient (MAC), mean free path (MFP), RSE, and transition factor (I/I 0) were calculated. The RSE values of the epoxy samples were E00 (63.41%), EB0 (87.17%), EBW1 (98.26%), EBW2 (99.82%), and EBW3 (99.99%) at an energy of 0.06 MeV with 4 cm thickness. With the increase in the incident energy, the half-value layer and MFP values were increased, whereas the LAC and MAC values decreased. In conclusion, it can be stated that the sample EBW3 is more suitable among the five epoxy samples studied for attenuating the incident photon energy from 0.06 to 1.33 MeV. Noteworthily, the obtained results demonstrate that the addition of WO3 nanoparticles enhances the shielding ability of epoxy when compared to the addition of the same amount of bentonite

Physical, mechanical, and gamma ray shielding properties of the Bi2O3–BaO–B2O3–ZnO–As2O3–MgO–Na2O glass system

This study provides insights into the effects of Bi2O3 on the physical, mechanical, and gamma ray shielding properties of Bi2O3–BaO–B2O3–ZnO–As2O3–MgO–Na2O glasses. The higher Bi2O3 concentrations result in increased density and molecular weight of the glasses. The molar volume also increases with higher Bi2O3 percentages, accompanied by a decrease in the average distance between boron atoms and a reduction in polaron radius and inter-nuclear distance. Electronegativity decreases and electronic polarizability increases with increasing Bi2O3 concentration, indicating higher electron-donating capacity and greater susceptibility to external electric field distortion. The elastic moduli exhibit a downward trend with increasing Bi2O3 concentration, indicating a decreased degree of elastic behaviour. The decrease in cross-linking is further supported by the reduction in Poisson’s ratio. The decrease in values of the hardness also indicates a decline in the stiffness and connectivity of the glass network. The linear attenuation coefficients (LACs) of three different glasses were obtained using Phy-X software in 0.015–15 MeV energy range. Also, the effective atomic numbers are calculated for the selected glasses. The LAC has the highest values for Bi21, indicating that the addition of Bi2O3 causes an improvement in the LAC

Thermoluminescence Sensitization of Phyllite Natural Rock

A sensitization procedure is used to enhance the thermoluminescence (TL) sensitivity of phyllite to emit radiation. Phyllite is a type of foliated metamorphic rock made from slate. This study examines naturally grown phyllite rock, which had not been previously studied. Using a Thermo 3500 manual reader, the TL sensitivity of phyllite as a function of dosage was measured. The doses required to perform this study were administered using a 60Co source. The statistical regression test of the data had a significance level of p < 0.05. The study also included thermal and pre-dose effects. Using the sensitization procedure, the nonlinearity in TL dose–response was removed, and the sensitivity was increased 44 times that of its original value. The fading study showed a dependence on the test dose. According to the obtained results, the combination of linear dose–response and high sensitivity to gamma radiation makes phyllite an important rock for dating and retrospective dosimetry

Morphological and Gamma-Ray Attenuation Properties of High-Density Polyethylene Containing Bismuth Oxide

For extensive radiation exposure, inventing a novel radiation shielding material is a burning issue at present for the purpose of life saving. Considering this thought, in this study, by adding sundry amounts of Bi2O3 into pure high-density polyethylene (HDPE), six HDPE systems were prepared to evaluate the radiation shielding efficiency. These HDPE systems were HDPEBi-0 (pure HDPE), HDPEBi-10 (10 wt% Bi2O3), HDPEBi-20 (20 wt% Bi2O3&minus;), HDPEBi-30 (30 wt% Bi2O3), HDPEBi-40 (40 wt% Bi2O3), and HDPEBi-50 (50 wt% Bi2O3). The values of the linear attenuation coefficients of the experimental results (calculated in the lab using HPGe) were compared with the theoretical results (obtained using Phy-X software) at 0.060, 0.662, 1.173, and 1.333 MeV energies. To ensure the accurateness of the experimental results, this comparison was made. It was crystal clear that for energy values from 0.06 MeV to 1.333 MeV, all the experimental values were in line with Phy-X software data, which demonstrated the research setup&rsquo;s reliability. Here, the linear attenuation coefficient (LAC), and mean free path (MFP) shielding parameters were assessed. At the energy of 1.333 MeV, sample HDPEBi-0 showed an HVL value 1.7 times greater than that of HDPEBi-50, yet it was 23 times greater at 0.0595 MeV. That means that for proper radiation protection, very-low-energy HDPE systems containing 10&ndash;50% Bi2O3 could be used; however, the thickness of the HDPE system must be increased according to the energy of incident radiation

Impact of WO3 and BaO nanoparticles on the radiation shielding characteristics of polydimethylsiloxane composites

In this study, we developed flexible composites using silicone rubber (SR) or polydimethylsiloxane as the matrix and WO3 and BaO nanoparticles as filler to analyze their radiation-shielding performance. The linear attenuation coefficient (LAC) values for the prepared composites were reported to range from 0.059 to 1.333 MeV by using the experimental method. At 0.059 MeV, the SR with 40% of BaO NPs possesses the highest LAC, followed by SR with 20% of BaO and WO3 NPs. The SRs S-2 and S-4 that contain WO3 and/or BaO exhibit continuously greater LAC values than the sample S-1. Numerically, the LAC for S-2 (with 40% of BaO NPs) is 1.6 times greater than that for S-1 (free BaO and WO3) at 0.662 MeV, while the LAC for S-2 is 1.47 times more than that for S-1 at 1.275 MeV. We examined the impact of the thickness of the prepared composites on the attenuation performance by studying the transmission factor (TF) at two different thicknesses (1 and 2 cm). For S-1 and S-2, the TF decreases due to the increase of the thickness from 1 to 2 cm. The TF for S-1 with a thickness of 1 cm is 75% at 0.059 MeV, while it is 56% (for 2 cm). We evaluated the percentage decrease in the TF at 0.059 MeV for every SR as the thickness changes from 1 to 2 cm. For S-3, S-4, S-5, and S-6, the percentage decrease in the TF is extremely significant varying from 98% to 99%. This suggests that increasing the thickness of these SR samples from 1 to 2 cm has a major effect on the shielding capabilities they possess, particularly at low energies

Preparation of newly developed porcelain ceramics containing WO3 nanoparticles for radiation shielding applications

We fabricated porcelain ceramics embedded with WO3 nanoparticles (NPs) for radiation shielding applications. The linear attenuation coefficients were experimentally determined to study the efficiency of the manufactured samples against gamma rays. When the thickness increases from 0.5 to 2 cm, there is a reduction in the photon transmission through the ceramics. At 0.662 MeV, the transmission factor for Porc-1 changes from 0.91 (thickness: 0.5 cm) to 0.83 (thickness: 1 cm), and to 0.69 (thickness: 2 cm). From I/I 0 results, we found that attenuation performance is improved as the sample thickness increases. We evaluated the mass attenuation coefficient (MAC) and examined the influence of the concentration of WO3 NPs on the MAC. We found that Porc-5 which contains a greater quantity of WO3 NPs compared to the other samples has the highest MAC. At 0.06 MeV, the HVL (half value layer) for Porc-1 is 1.063 cm, while at 1.333 MeV this increases to 5.247 cm. Meanwhile, for Porc-2, at 0.06 MeV, a thin layer of thickness 0.806 cm is required to shield 50% of the photons, and at 1.333 MeV, the thickness of the layer must increase to 5.058 cm to shield the photons