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This research examines the effects of varying titanium oxide (TiO 2) concentrations in glass formulations, denoted as [(53-x)B 2 O 3 –7MgO–20BaF 2 –20Na 2 O-xTiO 2 ] or BMBNTix, where x varies from 0 to 8 mol% in 2 % increments, on optical properties and radiation shielding effectiveness. Using MCNP5 (MC) Monte Carlo simulations and Phy-X software, this study assesses a range of photon energies from 0.015 to 15 MeV, focusing on key radiation shielding metrics such as the linear attenuation coefficient (μ), the half-value layer (HVL), and the tenth value layer (TVL). The results reveal a clear relationship between increased TiO 2 levels in the BMBNTix glasses and improved radiation shielding performance. Notably, the linear attenuation coefficient (μ) steadily climbs from BMBNTi0 to BMBNTi8, highlighting the beneficial effect of a TiO 2 addition to the material's ability to attenuate radiation. This trend is inversely mirrored in HVL values, which decrease from 0.010 cm for BMBNTi0 to 7.646 cm for BMBNTi8, reflecting enhanced shielding efficiency over the entire studied photon energy range. The effective atomic number (Z eff) also showcases a dynamic range from 40.793 to 15.101, suggesting a complex relationship between TiO 2 content and photon interaction. Moreover, the study indicates a slight but consistent increase in the fast neutron removal cross-section (Σ R) from 0.104 cm−1 for BMBNTi0 to 0.106 cm−1 for BMBNTi8, pointing to improved neutron shielding with greater Ti and oxygen content in the glass. These insights highlight the potential of TiO 2 -enriched magnesium borate glasses as superior options for effective photon and neutron shielding, particularly in nuclear medicine, emphasizing their role in enhancing radiation safety measures. [ABSTRACT FROM AUTHOR]

In the study of concavity properties of positive solutions to nonlinear elliptic partial differential equations the diffusion and the nonlinearity are typically independent of the space variable. In this paper we obtain new results aiming to get almost concavity results for a relevant class of anisotropic semilinear elliptic problems with spatially dependent source and diffusion. [ABSTRACT FROM AUTHOR]

The present investigation was aimed at the utilization of alternate materials, emphasizing hazardous industrial products (red mud and cathode ray tubes), as constituents of radiation shielding concrete. The usage of these hazardous industrial products improves the sustainability and performance of the radiation shielding concrete. Five concrete blocks were cast and their density, compressive strength, gamma shielding factors, radiation absorption ratio, and transmission factor were explored. For this purpose, gamma-ray shielding measurements were done with the help of an HPGe detector. Mix-1, with zero contents of red mud and CRTs, had the lowest LAC. The LAC results demonstrated that the shielding performance of the current concretes would be better with the increase in red mud and cathode ray tube glass. The Transmission factor (TF) for the prepared concretes with a thickness of 2 cm varied between 11.9–26.1% at 0.06 MeV, while it varied between 4–13% for a thickness of 3 cm. The TF results showed that the composites with a thickness of 2, 3, or 5 cm are good shields against lower energy radiation. The radiation absorption ratio (RAR) for the prepared concretes is high at low energy, suggesting that these new composites can absorb most of the low-energy photons. The RAR results emphasize that the increase in CRTs in the new composites enhanced the radiation shielding features, and when the CRT glass is at a maximum, more attenuation was achieved. [ABSTRACT FROM AUTHOR]

The mechanical behavior and gamma radiation attenuation features of borosilicate glasses with chemical compositions 16ZnO–8BaO-5.5SiO 2 -0.5Sb 2 O 3 -(70-x)B 2 O 3 /xBi 2 O 3 are extensively investigated. Makishima-Mackenzie principle, Monte Carlo code, and Phy-X/PSD software are utilized in terms of determining these properties. Our results showed that the total packing density (V t) decreased from 0.634851 to 0.571458, while the total dissociation energy increased from 26.612 (kJ/cm3) to 29.652 (kJ/cm3) for S1-glass (with 10 mol% of Bi 2 O 3) and S5-glass (with 30 mol% Bi 2 O 3). All elastic moduli are enhanced by increasing the Bi 2 O 3 additive in the investigated glasses. Poisson's ratio was decreased from 0.281226 for S1-glass to 0.256957 for S5-glass. In terms of gamma-ray shielding parameters; linear (μ) and mass attenuation (μ m) coefficients for the rich glass sample with B 2 O 3 (S5) possess the highest values among all investigated (S1–S5) samples. The glass sample S5 is reported with the lowest values of tenth (TVL) and half (HVL) value layers among all studied glasses. In addition, the exposure (EBF) and energy absorption (EABF) bulidup factors were decreased with increasing the amount of Bi 2 O 3 reinforcement for mean free path values from 0.5 to 40 mfp. The lowest possible levels of attenuation (minimum transmission) were measured at a thickness of 3 cm for all of the glass samples. • The mechanical behavior of borosilicate is intensively investigated. • Makishima-Mackenzie principle, and Monte Carlo code are utilized in terms of determining these properties. • Characterization of nuclear radiation shielding properties performed in-silico methods. • Obtained remarkably interesting results on B 2 O 3 –ZnO–BaO–SiO 2 –Sb 2 O 3 –Bi 2 O 3 glasses. • All the obtained results have been linked to their monotonical attitudes. [ABSTRACT FROM AUTHOR]

Chalcogenide composites, a category of non-oxide glasses, have shown great potential in various applications such as optoelectronics, thermal imaging, memory-switching devices, lasers, and more. Owing to the distinctive physical properties inherent in chalcogenide glasses, these materials have garnered significant interest across various technological domains. This study aims to analyze the impact of incorporating sulfur (S) and antimony (Sb) into (S3Sb2)x(S2Ge)100−x:x = 10, 20, 30 chalcogenide composites, assessing their radiation shielding, structural, physical, and electrical properties. Three distinct composites, designated as SSbGe-10, SSbGe-20, and SSbGe-30, are irradiated with gamma photons across an energy range of 0 to 15 MeV. The assessment of the radiation shielding attributes is conducted through the utilization of the FLUKA Monte Carlo (MC) Code. Phillips and Thorpe's theory is employed to analytically estimate structural and physical attributes such as Coordination Number (CN), bond-bending constraints (NS), bond-stretching constraints (NC), constraints Number (Ncons), Floppy mode (F), and stoichiometry (R). The electrical features of the provided specimens are analyzed through the utilization of the effective electron conductivity (Ceff), as ascertained by the Phy-X: PSD software. The findings indicate that the augmentation of the x value within the range of 10–30 wt.% positively augments the gamma photon shielding efficacy of the composite materials. Both NS and NC demonstrate diminishing patterns, encompassing the range of 2.64 to 2.575 and 7.56 to 7.30, respectively. Additionally, the stoichiometry (R > 1) for the investigated samples indicates that the chosen glasses are rich chalcogenide composites. The exhaustive examination of the physical, radiation shielding, and electrical characteristics of the prepared chalcogenide glasses provides valuable insights for subsequent investigations into various chalcogenide glass formulations. [ABSTRACT FROM AUTHOR]

Deposition of plasma energy during off-normal fusion reactor operational events delivers a transient heat flux of up to 100 MJ/m2 to the plasma-facing materials (PFMs). Understanding the exact material response to the extreme energy loading conditions plays a key role in establishing a realistic computational tool that simulates the fusion plasma–material interaction. Surface damage can occur due to vaporization, melting, spallation, and liquid splatter. However, splashing mechanisms such as boiling and splattering, which result from various liquid instabilities, appear to be the main mechanism contributing to the melt layer erosion. The primary focus of this article is melting and resolidification and the effect of redeposition of the eroded material on surface erosion. A set of selected PFMs was exposed to a plasma heat flux of up to 40 GW/m2 over a deposition duration of $200~\mu \text{s}$. The source of the high energy plasma used in this article is the Surface InteRaction Experiment at North Carolina State (SIRENS) plasma source, which used to simulate disrupted plasma conditions. The underlying erosion mechanisms involved in the formation, ejection, and solidification of molten droplets are investigated using the basic plasma equations and a plasma fluid model implemented in the simulation code. The net erosion and redeposition thickness due to erosion of the vapor and melt layer have been evaluated post-plasma exposure and compared to the experimental measurements. [ABSTRACT FROM AUTHOR]

Application of an energetic material (EM) in a liquid or gaseous form to electrothermal (ET) plasma discharge systems can provide an energetic plasma jet that has desirable parameters for launching applications. In this energetic ET concept, the EM is basically injected into the plasma source that is operated in an ablation-free regime. The discharge and EM combustion processes have been simulated using the ETFlowCom code, which is an in-house developed energetic ET plasma model. In this article, the ETFlowCom code is used to predict the energetic plasma jet parameters such as temperature, pressure, heat flux, and exit velocity. Different computational case studies have been conducted using a variety of EM mixtures. The simulation results show that the generated energetic plasma jet has the density on the order of 10271/m3, kinetic pressure on the order of hundreds of MPa, and an exit velocity that can reach up to 6 km/s. These parameters are found to be functions of the EM type and the mixing ratio as well. The jet parameters show strong potential for launching applicability. [ABSTRACT FROM AUTHOR]

This study was carried out to evaluate the distribution of naturally occurring radioactive materials (NORM) and radiological risk indexes in aerosol dust in Nicosia, Cyprus utilizing a high-resolution HPGe gamma-spectrometry. The activity concentrations of 226Ra, 232Th, and 40K in the selected aerosol dust samples ranged from 25.9–52.4, 21.7–46.3, to 471–1302 Bq kg−1, respectively. The average activity concentrations of 40K were found to be above the Earth's crust average. The internal and external hazard indexes are well below the acceptable limit in most dust samples. All investigated samples met the exemption dose limit of 0.3 mSv y−1. [ABSTRACT FROM AUTHOR]

Molten salt fission and fusion reactors hold promise for large-scale, carbon-free power generation, but only if the combined effects of simultaneous irradiation and corrosion on their structural materials can be predicted. Here commercial alloys (SS316L, Incoloy 800 H, Inconel 600) are corroded in molten fluoride salt at 650 ℃ while partially subjected to simultaneous proton irradiation. By comparing corrosion feature depth distributions, it is found that simultaneous proton irradiation accelerates the corrosion of SS316L and Incoloy 800 H, while Inconel 600 does not undergo radiation-accelerated corrosion. Simultaneous proton irradiation accelerates or decelerates corrosion proportional to the ratio of Ni to (Fe+Cr) content. • Simultaneous proton irradiation/corrosion was studied on commercial alloys in FLiNaK. • Radiation enhanced diffusion increases mass fluxes to corrosion features. • Proton irradiation affects FLiNaK corrosion proportional to alloy (Fe+Cr) content. [ABSTRACT FROM AUTHOR]

The blocking effect of 222Rn gas and its progeny by various face masks has been determined using a measurement system with a parallel AlphaGUARD detector. The theoretical approach of diffusion rate for different particle sizes was calculated. The filtering effect of the different masks followed the order N99 > surgical > N95 > double cloth > double cellulose > cloth > cellulose masks, respectively. Overall the blocking effect percentage ranged between 7.65 and 22.66%. The study indicated that the effect of a mask with high quality in filtering the gas of 222Rn and its decay products is more than the double-layer masks. [ABSTRACT FROM AUTHOR]

An electrothermal (ET) plasma source has been used to produce intense transient high heat flux to evaluate surface erosion and melting of plasma-facing materials. The source produces high heat flux relevant to expected conditions during disruption event in future large fusion devices. Surface vaporization has been evaluated for selected fusion-relevant materials under radiant energy deposition. Additional simulation included the effect of melting and splattering. Vapor and droplet formation and their associated shielding effect have been investigated in this paper to assess the difference between a developed boundary layer from only vapor or melt layer or the mixed vapor-melt layer with possible ejection of molten droplets away from the surface. Fully self-consistent erosion models are developed and implemented in the ET ETFLOW code in a new version ETFLOW-boundary layer to model the response of plasma-facing materials and their erosive behavior under transient ET plasma high heat fluxes closely similar to expected ones in future fusion large tokamaks. [ABSTRACT FROM AUTHOR]

Herein, the titled glass routed with silver nanoparticles (achieved using thermal–reducing agent) containing trivalent erbium ions was synthesized via the melt–quench process. The electronic microscopic and linear absorption outcomes of glasses confirmed the formation of Ag0 nanoparticles. The prepared glass specimen was annealed at 400, 450 and 500 °C, it was identified that the photoluminescence properties were highest at 450 °C. Therefore, we considered this 450 °C as optimized temperature, since further annealing at this temperature for different durations causes significant improvement in photoluminescence properties compared to the properties obtained at other temperatures. The annealing at 450 °C for was performed for 0, 5, 10, 15 and 25 h to understand the influence of annealing duration on the optical absorption, visible and infrared photoluminescence properties of the prepared glass system. The photoluminescence intensity and related parameters such as bandwidth, gain bandwidth and quantum efficiency and also lifetime values of excited state for infrared emission transition were improved monotonously with annealing duration. The augmentation in the investigated properties was ascribed to the local field–produced by silver nanoparticles and the energy transfer from silver nanoparticles to erbium ions. The outcomes instantiate that the titled glass embedded with silver nanoparticles containing erbium ions annealed for 15 h at 450 °C could be useful for optoelectronic and photonic applications. • The heat treatment was performed to tune the photoluminescence and spectroscopic properties of Er3+ doped in glasses. • TEM micrographs revealed the homogeneous distribution of Ag nanoparticles glass matrix. • The results instantiate the glass embedded with silver nanoparticles annealed for 15 h at is beneficial for optical amplifier and solid-state laser applications. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Transient grating spectroscopy (TGS), a non-contact ultrasonic materials analysis technique, is proposed to rapidly and indirectly assess relative void swelling resistance of multiple structural materials. Statistically significant changes in the frequency of probed surface acoustic waves (SAWs) suggest that newly developed steels containing nanosized precipitates show higher resistance to void swelling when compared to their simpler, commercial analogues. The higher reduction in SAW frequency seen in the simpler steels, proportional to porosity, indicates more void formation which is directly validated by TEM examinations. This example illustrates the minimum set of targeted TGS studies required to quickly and inexpensively rank materials by relative void swelling resistance, and hence, accelerate materials development and characterization. • Using the TGS technique to quickly reveal void swelling rapidly and non-destructively. • Sensing changes in SAWs frequency has shown the advanced steels possess higher resistance to void swelling compared to the reference steels. • The TEM examinations have confirmed the TGS findings on the void swelling resistance of the reference and advanced steels. • This finding open the doors for extending the range of applicability of TGS technique in quickly and indirectly revealing irradiation defects. [ABSTRACT FROM AUTHOR]

This study investigates the naturally occurring radionuclides in Egyptian black sands collected from the Mediterranean Sea Coast, an area rich in sediments from the White Nile, Blue Nile, and Atbara rivers. The black sands mainly comprise two groups of minerals: the gangue group, consisting of quartz, feldspar, amphiboles, pyroxenes, epidote, and micas, and the economic minerals group, which includes magnetite, garnet, zircon, monazite, and uncommon commercial minerals like thorite. A gamma spectrometry with a NaI (Tl) detector was employed to analyze black sand samples for the presence of radionuclides. Additionally, radium equivalent activities (Raeq), absorbed dose rate, annual effective dose, gamma radiation hazard index (Iγ), external hazard index, internal hazard index (Hin), and lifetime cancer risk (ELCR) were calculated based on the measured activity concentrations of 226Ra, 232Th, and 40K. This comprehensive analysis contributes valuable insights into the radiological properties and potential hazards associated with Egyptian black sands. Due to the significant radioactive risk associated with these black sand samples, specifically in the Mediterranean Sea Alexandria coastal area, must be considered while using them as building materials. Measured values include Ra-226 (56 Bq/kg), Th-232 (77 Bq/kg), and K-40 (55 Bq/kg). [ABSTRACT FROM AUTHOR]

This study mainly focuses on the thermoluminescence features and trap parameter analysis of Sr 2 Al 2 SiO 7 :Dy3+ phosphors prepared via the low-temperature combustion method. The phase confirmation, structural and morphological studies are performed using XRD, FTIR, SEM and EDX characterizations. The energy gap of pure and Dy3+ doped phosphors is calculated. And the band gap decrease with doping. The optimum concentration was 3 mol% from the emission spectra; hence, this sample was irradiated with 3 Gy–5 kGy gamma doses. The samples showed high sensitivity and the MDD value is 0.21 mGy. The trap parameters were determined following deconvolution of the glow curves. Four traps were found in the samples, and the trap lifetime increased with increasing gamma dose. The trap depth increased The linear response from 3 Gy to 250 Gy implies that the prepared samples could be used as γ dosimeters within this range. [ABSTRACT FROM AUTHOR]

This study examined the radiation shielding features of ball clay-cement-iron slag as an alternative to concrete. Using a variety of cement, ball clay, and iron slag compositions, six samples were fabricated. The linear attenuation coefficient (LAC) was experimentally reported using three point sources (Am-241, Cs-137and Co-60) and a HPGe detector. The results show that the LAC Exp and LAC XCOM values for the ball clay-cement-iron slag composites harmonized well. For the composite, the difference between the LAC values for the composite, 0.06 MeV, is notable; at the same time, they are almost negligible at 0.662 and 1.173 MeV. At 0.06 MeV, the difference between the LAC, from C1 and C6 is 0.56; yet, it is only 0.017 and 0.013 at 0.662 and 1.173 MeV. The LAC results confirm that adding iron slag to the prepared composites has a positive impact on their radiation attenuation competence. The composite's half value layer (HVL) at 0.06 MeV is reduced by about half when the iron slag content changes by 50 w.t%. According to the HVL results, the current alteration to iron slag contents reduces the influence of gamma photons. • The LAC of ball clay-cement- iron slag composites were reported. • A good harmony was reported between the LAC Exp and LAC XCOM values. • The Z eff for the prepared ball clay-cement- iron slag composites were determined. • The LAC was increased with adding iron slag to the composites. [ABSTRACT FROM AUTHOR]

The compound BiFe0.7Mn0.3O3 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. [ABSTRACT FROM AUTHOR]

The present study investigates the structural, thermal, and optical properties of Sm3+-doped Zinc Alumino Borosilicate (ZABS) glasses obtained through the melt-quenching method. The prepared glasses clearly exhibit an amorphous nature confirmed by XRD analysis. Through FTIR studies, the vibrations of metal cations, B 2 O 3 , SiO 2 , Al 2 O 3 network groups and O H groups were analysed. This study helps to determine the bridging and non-bridging oxygen quantity in glass structures including Sm 2 O 3. Through differential thermal studies, the thermal stability factor and its related calculations were carried out. Glasses showed a thermal stability (ΔT) value > 100 °C. Absorption spectra of the glasses showed thirteen peaks emerged from the lower ground state 6H 5/2. The bonding parameter calculation showed that the glasses exhibit ionic bonding. The Judd-Ofelt (J-O) parameters followed the same trend Ω 4 >Ω 2 > Ω 6 for the synthesized glasses. The bandgap values of the glasses decrease with higher content of NBOs in the glass network, and the Urbach energy (E U) increases. The luminescence spectra of the glasses show four emission peaks such that the intense emission is seen at transition 4G 5/2 → 6H 7/2 at 599 nm. The radiative parameters calculation showed that Sm3+- 0.5 mol% glass has a higher emission cross section (σ se) and transition probability (A R). Decay curves were recorded for all the glasses that show single exponential behavior with extended lifetimes (ms). Glasses produce reddish-orange emissions under 402 nm excitation and the values of correlated color temperature (CCT) lie in the range of 1500–1600 K. Overall, the prepared Sm3+-doped ZABS glasses act as a good candidate for luminescent display applications and laser materials. [ABSTRACT FROM AUTHOR]

In this work, we fabricated a new composition of TeO 2 –SrO–B 2 O 3 -MO (when RO = PbO, BaO, ZnO, and MoO 3) by using the melt quench technique. The role of various modifiers on strontium boro-tellurite glass was explored by studying structural, optical, and gamma-ray shielding properties. The structure for the glass was examined by X-ray diffraction (XRD), Fourier Transform Infrared (FTIR), and physical properties. The band gap, Urbach energy, refractive index, cut-off wavelength, etc., were determined based on the absorption ultraviolet (UV) spectrum. The gamma-ray shielding properties were defined experimentally and compared with XCOM data. The XRD data illustrated the amorphous nature of all glass samples and the FTIR results affirmed the functional groups for borate and tellurite. The highest density was recorded for a sample containing lead (SBT:Pb), followed by barium (SBT:Ba), Molybdenum (SBT:Mo), and Zinc (SBT:Zn). The experimental mass attenuation coefficient (MAC) exp showed excellent compatibility with XCOM data, and the highest relative difference (RD) was 7.47. In conclusion, the SBT:Pb sample showed the maximum radiation shielding properties, making it a strong option for use in radiation shielding. [ABSTRACT FROM AUTHOR]

Arranged from oldest to youngest, the main granitic rock units exposed in Khour Abalea are metagabbros, cataclastic rocks, ophiolitic melange, granitic rocks, pegmatite and lamprophyre dykes. The presence of radioactivity associated with the heavy bearing minerals in construction materials—like granite—increased interest in the extraction process. As it turns out, granitic rocks play an important economic part in the examination of an area's surroundings. The radionuclide content is measured by using an NaI (Tl)-detector. In the mineralized pegmatites, U (326 to 2667 ppm), Th (562 to 4010 ppm), RaeU (495 to 1544 ppm) and K (1.38 to 9.12%) ranged considerably with an average of 1700 ppm, 2881.86 ppm, 1171.82 ppm and 5.04%, respectively. Relationships among radioelements clarify that radioactive mineralization in the studied pegmatites is magmatic and hydrothermal. A positive equilibrium condition confirms uranium addition to the studied rocks. This study determined 226Ra, 232Th and 40K activity concentrations in pegmatites samples and assessed the radiological risks associated with these rocks. The activity concentrations of 226Ra (13,176 ± 4394 Bq kg−1), 232Th (11,883 ± 5644 Bq kg−1) and 40K (1573 ± 607 Bq kg−1) in pegmatites samples (P) are greater than the global average. The high activity of the mineralized pegmatite is mainly attributed to the presence of uranium mineral (autunite), uranophane, kasolite and carnotite, thorium minerals (thorite, thorianite and uranothorite) as well as accessories minerals—such as zircon and monazite. To assess the dangerous effects of pegmatites in the studied area, various radiological hazard factors (external, internal hazard indices, radium equivalent activity and annual effective dose) are estimated. The investigated samples almost surpassed the recommended allowable thresholds for all of the environmental factors. [ABSTRACT FROM AUTHOR]

In this work, six borate-bismuth glasses have been synthesized using a conventional melt-quenching-aneling process with a composition of (80-x)B 2 O 3 10ZnO 10MgO-xBi 2 O 3 where x = 10, 20, 30, 40, 50 and 60 mol%. The glasses were melted at 975 °C for 30 min and annealed at 300 °C for 5 h. Different physical properties of these glasses have been measured and estimated. X-ray diffraction has been utilized to investigate the structural nature of these glasses. Optical absorption and transmittance spectra have been measured for all samples in the range of 300–800 nm at room temperature. The cutoff wavelength of all glass samples was determined. In addition, the radiation shielding characterization for the glass samples was done by calculating the linear and mass attenuation coefficients, mean free path, and half value layer of the photon energy ranges between 0.015 and 15 MeV using MicroShield. It was found that the glass with the highest Bi 2 O 3 content showed the best performance in attenuating gamma radiation by exhibiting the highest linear attenuation coefficient and both lowest mean free path and half value layer due to its high density of 7.107 g/cm3. • B 2 O 3 ZnO MgO Bi 2 O 3 glasses were prepared by conventional melt-quenching method. • Optical absorption has been measured for all samples in the range of 300–800 nm. • The radiation shielding parameters were reported using MicroShield. • Bi60 sample showed the best performance in attenuating gamma radiation. [ABSTRACT FROM AUTHOR]

• The heat treatment at 450 °C for different durations was performed to tune the photoluminescence and spectroscopic properties of Nd3+ ions doped in glasses. • TEM micrographs revealed the homogeneous distribution of spherical shaped Ag nanoparticles glass matrix. • The results instantiate that Nd3+ ions doped in titled glass embedded with silver nanoparticles annealed for 15 hrs at 450 °C is beneficial for optical amplifier and laser applications. Method of melting and quenching was used to prepare the alkali borate–based glasses embedded with Nd3+ ions and silver nanoparticles (Ag NPs). In the as–prepared glass, silver NPs were formed by loading the thermal reducing agent such as antimony trioxide in the composition. The optical absorption and microscopic outcomes confirmed the growth of silver NPs in the prepared glass system. The prepared glass was annealed at 450 °C for 0, 5, 10, 15, and 25 hrs to tune the spectroscopic and photoluminescence features of Nd3+ ions loaded in the glass. The photoluminescence intensity and related features were enhanced continuously with heat treatment schedule. However, subsequently the features were reduced at longer schedule. The variation of these features was ascribed to the local field–generated silver NPs. The results revealed that the entitled glass could be utilized for photonic and optoelectronic applications when activated with Nd3+ ions and routed with Ag NPs. [ABSTRACT FROM AUTHOR]

This work aims to modify the shielding properties of liquid radioactive waste (LRW) containers used in nuclear power plants (NPP) for cooling water treatments. The proposed modified container consists of three main layers: a stainless steel inner capsule, halloysite clay filler, and an outer cementation concrete layer. A Monte Carlo simulation was used to estimate the absorbed and equivalent doses (μSv) around the LRW container. The dose rate is affected by the thickness of the inner capsule as well as the halloysite filler. The results show that increasing capsule thickness by 0–3 cm reduces the equivalent dose rate by 82.89%. Increasing filler thickness by 0–17 cm reduces the equivalent dose rate by 15.26%. The proposed container has many other advantages. It can reduce radioactive waste by 99.85% and is not expensive — due to the low price of concrete and halloysite. As a result, it is a good candidate for use in the dry disposal of radioactive wastes. • The absorbed and effective doses for a three-layer container were simulated used in the. • The container inner capsule can reduce the radioactivity by 82.83%. • The filler halloysite layer with thickness of 17 cm can reduce the activity by 15.26%. • The container cover is cementation concrete with thickness of 15 cm and can reduce radioactivity by 1.77%. [ABSTRACT FROM AUTHOR]

This paper proposes an innovative utilization method of boron bearing blast furnace slag (B3FS) as a highly cost-effective shield for protection against neutron radiation hazards, thereby conserving natural resources and preventing environmental pollution. Characteristic of the shielding performance of the prepared composites against thermal neutrons were tested by an Am–Be neutron source combined with the Evaluated Nuclear Data File. To analyze shielding performance, the following parameters were employed: shielding percentage, macroscopic cross section, and partial macroscopic cross section. Shielding percentage of the prepared shielding composites ranged between 76% and 80.5%, which increased with the additional amount of B3FS and positively correlated with the density and the boron content of the prepared shielding composites. In addition, shielding ability of the prepared shielding composites proved to be superiour to some commercially available shields. This paper proposes a shielding mechanism against thermal neutrons in the prepared shielding composites. It was demonstrated that the thermal neutron radiation shielding effect was achieved by the absorption of Mg 2 B 2 O 5 and the elastic scattering of epoxy resin matrix. The maximum resistance temperature of prepared shielding composites is about 230 °C, and bending strength exceeds 14 MPa. [Display omitted] • An innovative utilization method of boron bearing blast furnace slag is proposed. • Macro cross section for thermal neutron of B3FS is higher than commercial shields. • Shielding ability of prepared composites is better than some commercial shields. • Thermal neutron shielding mechanism in multiphase materials is first proposed. • Bending strength of the prepared composites is higher than 14 MPa. [ABSTRACT FROM AUTHOR]

The void swelling behavior of a newly developed austenitic stainless steel with uniformly distributed nanosized NbC precipitates (ARES-6) and commercial 316 stainless steel was evaluated using the heavy ion irradiation. The 5 MeV Ni3+ ion was irradiated at 500 °C to a dose of 8.5 dpa with a dose rate of 1.8 × 10−3 dpa/s at 600 nm from the surface. Measured at 600 nm region, ARES-6 showed nearly seven times less swelling compared to that of 316 stainless steel. By comparing the swelling for the solution annealed and hot-rolled ARES-6, it was confirmed that NbC precipitates as well as high Ni content contributed to the improved swelling resistance of the alloy. The dissolution of nanosized NbC precipitates during irradiation was observed, which could be the reason for the large discrepancy between estimated and observed swelling resistance of ARES-6. [ABSTRACT FROM AUTHOR]

• Use of F-Ba and Pb-Zn mine waste as fine aggregate substitute in mortar. • It is feasible to use the tailings to replace heavy aggregates. • Mortar made with Pb-Zn tailing has lower mechanical properties than mortar made with F-Ba tailing. • Promising aspects for sustainable shielding mortar made with F-Ba and Pb-Zn tailings. The use of mine waste and tailing in concrete and mortar has widely expanded in the past years. Several studies aim to contribute to the recovery of these rejects and preserve natural raw materials, on the other hand, to improve the physio-mechanical performance of concrete. In the present investigation, the impacts of Pb-Zn and F-Ba as fine aggregate replacement in mortar were analyzed. The outcomes indicated that substitution materials affect the mechanical strength and gamma radiation shielding properties of the mortar. In this regard, the compressive strength of samples made with substitutions of 5%, 10% and 20% of F-Ba tailings were slightly decreased with those of the reference test. However, the replacements with Pb-Zn tailings cause a significant strength decrease of mortar samples (from 68% to 94%). On the contrary, the flexural strength was improved adding one of these types of tailing. Concerning the absorption properties for gamma radiation, obtained results show that incorporation of these solid residues increases the attenuation of gamma rays. The mortars made with F-Ba tailings are more effective than others. The influence of tailings is significant mainly between 0.122 and 0.622 MeV and the highest attenuation is observed for Sample 5′ and 6′. This could be explained by the relative content of heavy minerals in each waste. Furthermore, the half thickness decreases with the increase of mine tailings percentage. The difference is more marked at high energies up to 0.15 MeV. Subsequently, the obtained materials could be utilized for shielding against gamma radiation. [ABSTRACT FROM AUTHOR]

Glass gained much attention to be utilized in various applications, for this reason different kinds of glass compositions was the subject of investigation. In this work, we successfully fabricated a series of tellurite–germanate glasses with a composition of (70-x)TeO2–10GeO2–10ZnO–10Li2O–xBi2O3, where x = 0, 5, 10 and 15 (all in mol%). Ordinary melt-quenching was used to synthesize the mentioned glass series with 975 °C as a melting temperature for 30 min and 300 °C for annealing to release the internal stress. To study the structural properties of these glasses, X-ray diffraction (XRD) was used to confirm the glassy structure of these glasses. Regarding that, XRD profiles were recorded in ranges between 10° and 80° for all samples. Moreover, FTIR was employed to study the functional groups of all elements, which were used in the composition with the range of 4000–400 cm−1. Optical absorption was used to investigate the cutoff wavelength and optical band gap. Optical absorption was measured at the range of 200–800 nm. The variation of the attenuation properties for the tested tellurite–germanate glasses has been investigated using WinXcom software for photon energy ranges between 0.015 and 15 MeV. The examined attenuation properties include linear and mass attenuation coefficients, half value layer and mean free path, and effective atomic number of the radiation shielding glass. The present results suggest the utilization of the new prepared glass samples in radiation shielding applications. [ABSTRACT FROM AUTHOR]