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The impact of chromium oxide (Cr2O3) on the organizational, physical, mechanical, and photon shielding qualities of new chromium borate glasses with the chemical composition 50B2O3-25Bi2O3-25Li2O3-xCr2O3 (x=0 (Cr-00), 0.2 (Cr-0.2), 0.4 (Cr-0.4), 0.8 (Cr-0.8), and 1.5 (Cr-1.5) wt%) is investigated. The amorphous behavior of these glasses was verified via X-ray diffraction (XRD) and scan electron microscope (SEM) micrographs. Fourier transform infrared (FTIR) spectra of prepared glass samples revealed the presence of absorption bands due to Cr3+ ions. The density (ρglass) increased as the Cr2O3 concentration increased. The mass attenuation coefficients (MACs) of the proposed glasses were evaluated via the FLUKA code, XCOM program, and Phy-X/PSD software. The MACs values followed this trend: (MAC)Cr-00 < (MAC)Cr-0.2 < (MAC)Cr-0.4 < (MAC)Cr-0.8 < (MAC)Cr-1.5. At 0.015 MeV, the calculated linear attenuation coefficient (LAC) values were 127.913, 133.559, 137.984, 147.034, and 156.212 cm-1 for the Cr-00, Cr-0.2, Cr-0.4, Cr-0.8, and Cr-1.5 glass samples, respectively. The half-value layer (HVL) and mean free path (MFP) values followed this trend: (MAC,MFP)Cr-00 > (MAC,MFP)Cr-0.2 > (MAC,MFP)Cr-0.4 > (MAC,MFP)Cr-0.8 > (MAC,MFP)Cr-1.5. The Cr-00 glass sample had the lowest effective atomic number (Zeff) values, while the Cr-1.5 glass sample had the highest. The calculated exposure buildup factor (EBF) values decreased as the Cr2O3 content increased. The Cr-1.5 sample had a higher effective removal cross-section for fast neutrons (ΣR) value than other radiation shielding materials. The addition of Cr2O3 increased the rigidity and elastic constants (Young's (Y), bulk (K), shear (G), and longitudinal (L) moduli) and improved the level of radiation shielding provided. The prepared glasses can be used as gamma and neutron shielding tools in the medical area. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the response of the radiology workforce to the impact of the coronavirus disease 2019 (COVID-19) pandemic on professional practice in India and eight other Middle Eastern and North African countries. It further investigated the levels of fear and anxiety among this workforce during the pandemic. A quantitative cross-sectional study was conducted using an online survey from 22 May-2 June 2020 among radiology workers employed during the COVID-19 pandemic. The survey collected information related to the following themes: (1) demographic characteristics, (2) the impact of COVID-19 on radiology practice, and (3) fear and (4) anxiety emanating from the global pandemic. We received 903 responses. Fifty-eight percent had completed training on infection control required for handling COVID-19 patients. A large proportion (79.5%) of the respondents strongly agreed or agreed that personal protective equipment (PPE) was adequately available at work during the pandemic. The respondents reported experiences of work-related stress (42.9%), high COVID-19 fear score (83.3%) and anxiety (10%) during the study period. There was a perceived workload increase in general x-ray and Computed Tomography imaging procedures because they were the key modalities for the initial and follow-up investigations of COVID-19. However, there was adequate availability of PPE during the study period. Most radiology workers were afraid of being infected with the virus. Fear was predominant among workers younger than 30 years of age and also in temporary staff. Anxiety occurred completely independent of gender, age, experience, country, place of work, and work status. It is important to provide training and regular mental health support and evaluations for healthcare professionals, including radiology workers, during similar future pandemics. [ABSTRACT FROM AUTHOR]

Bioactive glasses are renowned for their applications in dentistry, serving as restorative materials, dental adhesives, intracanal medicaments, and agents for enamel remineralization. Niobium pentoxide (Nb 2 O 5) is employed in dental adhesive resins and orthodontic adhesives, offering radio-pacifying properties essential for dental materials. Samarium oxide (Sm 2 O 3) emerges as a potential additive in aesthetic restorative dental ceramics and resins, enhancing the natural fluorescence of teeth. In this study Nb 2 O 5 and Sm 2 O 3 -doped (1, 3, and 5 wt%) 13–93 bioactive glass particles were synthesized via the sol-gel method, tailored for dental implementations. We conducted a comprehensive analysis of the physical, structural, and optical properties of the resultant glass powders. Additionally, their in vitro bioactivity and ionizing radiation shielding characteristics were rigorously evaluated. The results indicate that Sm3+ ions preserve the amorphous nature of the silicate glasses, while Nb5+ incorporation leads to the crystallization of the T-Nb 2 O 5 phase. Bioactivity assays across three physiological fluids—simulated body fluid, α-minimum essential medium, and phosphate-buffered saline, demonstrated the ability of doped glasses to facilitate hydroxyapatite layer formation, with the most pronounced bioactivity observed in phosphate-buffered saline immersed samples. Furthermore, radiation shielding simulations reveal that the addition of Nb 2 O 5 and Sm 2 O 3 enhances the ionizing radiation attenuation capabilities of the glasses, a property that holds significant promise for protecting against radiation in dental radiology. It can be concluded that the dual functionality of Nb5+ and Sm3+-doped bioactive glasses, which may revolutionize restorative dental practices and offer improved protection in radiological applications. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the protective properties of Bi 2 O 3 heavy metal oxide-doped glassy portable containers and the effect of reinforcement amount on these properties using the MCNPX (version 2.6.0) general-purpose Monte Carlo code. Accordingly, 60Co and 137Cs radioisotopes were defined as point isotropic radioactive sources to be transported with the newly designed containers. Four containers with different heavy metal oxide additives varying between 5% and 20% were designed and the deposited energy (MeV/g) values in the air were calculated for both 60Co and 137Cs radioisotopes. According to the findings of the first phase of the investigation, the sample (S4) with a 20% Bi 2 O 3 additive ratio showed the highest protective properties and the least amount of deposited energy amount in the air. In the second and benchmarking phase of the investigation, we compared the amount of deposited energy in the air for the superior S4 glass container and a concrete container with a high amount of bitumen additive. The findings demonstrated that the S4 portable glass container with a 20% Bi 2 O 3 reinforcement provided significantly lower deposited energy in the air and therefore greater nuclear safety than the concrete container. Heavy metal oxide-doped glass may be considered a viable choice for nuclear waste management and transportation operations due to its nuclear safety properties and superior physical, optical, and mechanical capabilities in comparison with concrete. • Heavy metal oxide-doped glassy portable containers were designed. • MCNPX (version 2.6.0) general purpose Monte Carlo code was used. • 60Co and 137Cs radioisotopes were used as point isotropic sources. • Deposited energy (MeV/g) amount has been measured. • S4 container with a 20% Bi 2 O 3 reinforcement provided significantly lower deposited energy in the air. [ABSTRACT FROM AUTHOR]

Radioisotopes are used extensively in nuclear medicine. Analysis of occupational doses received by medical radiation workers, especially nuclear medicine staff dealing with radioisotopes, contributes significantly to enhancing safe practice and promoting radiation protection measures in the radiology department. The current study aimed to determine the time trend and the differences in occupational radiation dose among nuclear medicine workers. Readings of 394 OSL dosimeters were obtained from 31 medical workers and grouped into five worker groups (technologist, physician, nurse, radio-pharmacist, and radio-physicist). The average number of workers dropped to 4.5 in 2020 and 2021 compared to 14.4 in 2014 to 2019. The average annual effective dose and skin dose for all workers based on measurements for a typical yearly workload of 5000 patients were 1.21 (±1.15) mSv and 2.86 (±1.32) mSv, respectively. The highest average annual effective and skin dose was 5.41 and 5.82 mSv, respectively. The NM technologist working in PET/CT received higher mean and maximum effective and skin doses than the other worker groups. The annual effective and skin doses were below the national legislation and international standards. However, improvements in radiation protection practices could be implemented to reduce occupational radiation dose to NM technologists, the most exposed worker group in this study. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nuclear radiation shielding and elastic aspects of different B 2 O 3 -based glasses are examined. • 50B 2 O 3 -10K 2 O-40Li 2 O (mol%) glass shows superior fast neutron attenuation ability. • 25B 2 O 3 -37.5Si 2 O-37.5Gd 2 O 3 (mol%) glass exibits better thermal neutron absorption potency. • 15B 2 O 3 -10ZnO-5Li 2 O-70Bi 2 O 3 (mol%) glass possesses dominant gamma-ray shielding capacity. • Mechanical features are estimated by applying bond compression and Makishima–Mackenzie models. Adequate shielding from ionizing radiations is essential in nuclear facilities because of such radiations' adverse effects on humans in the event of unwanted or accidental exposure. In the current work, for four distinct compositions of B 2 O 3 -Li 2 O, Li 2 O-Na 2 O-K 2 O-B 2 O 3 , Gd 2 O 3 -SiO 2 -B 2 O 3 , and Bi 2 O 3 -Li 2 O-ZnO-B 2 O 3 glass systems, neutron and γ -ray attenuation competencies combined with elastic features have been examined for feasible nuclear radiation protection purposes. Σ R (fast neutron removal cross-section) and for thermal energy neutrons σ T (total cross-section) and SP (shielding percentage) were estimated. Comparably, in all samples, 50B 2 O 3 -10K 2 O-40Li 2 O (mol%) glass possesses larger Σ R (=0.11755 cm−1), whereas 25B 2 O 3 -37.5Si 2 O-37.5Gd 2 O 3 (mol%) glass shows large σ T (=646.171 cm−1) and SP for thermal neutrons at minimal thickness, indicating the included Gd 2 O 3 's positive effect as element Gd has a high neutron absorption capacity. Employing the Phy-X/PSD program and MCNPX code, μ/ρ (mass attenuation coefficient) of all selected glasses is calculated for a γ -ray energy span of 0.015 – 15 MeV. Gd 2 O 3 or Bi 2 O 3 addition improved μ/ρ , and such increment is significant at low energies owing to PEA (photoelectric absorption) dominance and Gd or Bi K -edges. Also, for 15B 2 O 3 -10ZnO-5Li 2 O-70Bi 2 O 3 (mol%) glass, μ/ρ has been derived by the WinXCOM program and FLUKA, Geant4, and PHITS codes, and a good accord between such simulated and theoretical μ/ρ outcomes is noticed following the calculated relative differences. Next, linear attenuation coefficient , effective atomic number and electron density, MFP (mean free path), TVL (tenth-value layer), HVL (half-value layer) , and RPE (radiation protection efficiency) have also been evaluated. Comparatively, at 1.25, 0.662, and 0.2 MeV energies, 15B 2 O 3 -10ZnO-5Li 2 O-70Bi 2 O 3 (mol%) sample possesses lower MFP and HVL than five SCHOTT AG commercial glass shields. Approximated RPE results affirmed all Gd 2 O 3 -SiO 2 -B 2 O 3 and Bi 2 O 3 -Li 2 O-ZnO-B 2 O 3 samples' potent absorption (almost 100%) ability for lower energy γ -rays. Moreover, equivalent atomic number, and by geometric progression fitting process, within energy 15 keV–15 MeV extent for ten different penetration depths at 1–40 mfp span buildup factors have been assessed. 15B 2 O 3 -10ZnO-5Li 2 O-70Bi 2 O 3 (mol%) glass exhibits better gamma-ray shielding effectiveness in all chosen samples, specifying Bi 2 O 3 's favorable impact. Changes in photon shielding factors were interpreted following pair production, Compton scattering, and PEA processes. Later, elastic (Young's (Y), bulk (K), shear (S), and longitudinal (L)) moduli and Poisson's ratio values have been calculated for all inspected glasses. BC (bond compression) and M-M (Makishima–Mackenzie) models were utilized for such elastic traits reckoning. All K , Y , S , and L values' trends for binary B 2 O 3 -Li 2 O glasses were identical in both BC and M-M models, and K bc was found to be raised from 73.63 to 89.89 GPa, while K M–M increased from 75.35 to 180.53 GPa accordingly when Li 2 O content improved from 9.6 to 39.9 mol% in the chemical composition. [ABSTRACT FROM AUTHOR]

In this work, a new phosphate glass system with the nominal compositions 65P 2 O 5 +10Li 2 O +(25-x)BaO + xBi 2 O 3 was fabricated by using the conventional solid-state technique. Phosphate glasses were evaluated for their suitability in optical and radiation shielding applications. The amorphous nature of manufactured glasses was proved by utilizing an X-ray diffraction pattern. The density of glass samples was enhanced with rising Bi 2 O 3 substitution ratio. UV–Vis absorption spectra were measured based on the concentration of Bi 2 O 3 in PLBB glasses, optical energy band gap E g for indirect and direct transitions were decreased from 3.43, 4.25 to 3.15, 3.95 eV with enhancing Bi 2 O 3 substitution ratio respectively while urbach energy E u was increased from 0.632 to 0.661 eV. The single oscillator energy (E o) was found to decrease with increasing Bi 2 O 3 however the average oscillator wavelength (λ o) was increased. The Gamma-ray attenuation features of PLBB glasses were obtained via EpiXS program and MCNPX simulation codes. Mass attenuation coefficients (MAC) for PLBB0 and PLBB25 glasses were determined in the range of 14.995–0.0247 cm2/g and 43.912–0.0335 cm2/g, respectively. Outcomes obtained from MAC values and other photon shielding parameters such as MFP, HVL, Z eff , N el , and EBF revealed that the replacement of Bi 2 O 3 with BaO improves the capacity of PLBB glasses to reduce the intensity of gamma-rays. Furthermore, the macroscopic neutron cross section of PLBB25 glass with 25% Bi 2 O 3 substitution is 0.133 cm−1 while it is 0.113 cm−1 for PLBB0 glass. The increase of Bi2O3 addition to the new phosphate glass system has remarkably improved both optical and nuclear radiation protecting properties. [ABSTRACT FROM AUTHOR]

This study aimed to investigate a specific lithium-fluoro borotellurite glass system based on (60-x)B 2 O 3 -xTeO 2 -5LiF–5BaO–5Bi 2 O 3 (x = 25, 35, 45, 55, 65, 75, and 85 mol %) composition encoded as BTLBB1- BTLBB7 in terms of their optical, mechanical characteristics, and gamma ray attenuation competencies. The Rmolar possess the values 22.064, 21.546, 21.038, 20.860, 19.998, 18.936, and 20.024 (cm3/mol), while the αmolar possess the values 8.755, 8.550, 8.348, 8.278, 7.936, 7.514, and 7.946 (cm3) for BTLBB1, BTLBB2, BTLBB3, BTLBB4, BTLBB5, BTLBB6, and BTLBB7, respectively. Values of χ(3) were 5.189 × 10−12, 5.150 × 10−12, 4.995 × 10−12, 4.448 × 10−12, 4.624 × 10−12, 4.995 × 10−12, and 5.812 × 10−12 (esu), while values of n 2 o p t i c a l were 7.821 × 10−11, 7.768 × 10−11, 7.558 × 10−11, 6.813 × 10−11, 7.054 × 10−11, 7.558 × 10−11, and 8.656 × 10−11 for BTLBB1, BTLBB2, BTLBB3, BTLBB4, BTLBB5, BTLBB6, and BTLBB7, respectively. The highest μ m values were found for BTLBB7 glass sample (TeO 2 = 85 mol%) and obey the trend: (μ m) BTLBB7 > (μ m) BTLBB6 > (μ m) BTLBB5 > (μ m) BTLBB4 > (μ m) BTLBB3 > (μ m) BTLBB2 > (μ m) BTLBB1. The T 1/2 values were reported as 0.105 cm, 0.092 cm, 0.082 cm, 0.075, 0.067, 0.058 and 0.057 cm for those BTLBB1, BTLBB2, BTLBB3, BTLBB4, BTLBB5, BTLBB6 and BTLBB7 at 0.1 MeV photon energy, respectively. The BTLBB7 sample has the highest overall effective atomic numbers Z eff (55.04), while BTLBB1sample has the lowest values (50.33) at 0.1 MeV photon energy. The BTLBB1sample was reported the maximum EBF and EABF values, while the minimum values were reported for the BTLBB7 sample. The investigated glasses can be used as good candidate for optical fibers, photonic devices, and superior in terms of gamma-photon attenuation capability. • Samples of lithium-fluoro borotellurite glasses were chosen. • Optical and mechanical properties were investigated. • γ-ray attenuation properties have been examined. • Glasses can be used as good candidate for optical applications. • Glasses are superior in terms of gamma-photon attenuation capability. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nuclear radiation shielding aspects and physical and mechanical features of ternary B 2 O 3 -Bi 2 O 3 -BaO glasses are explored. • Phy-X/PSD, MCNPX, Geant4, FLUKA, and SRIM codes are used to evaluate γ -, α -, proton, and neutron attenuation factors. • 25B 2 O 3 -70Bi 2 O 3 -5BaO (mol%) glass exhibits superior γ -ray and fast neutron attenuation ability. • Different physical characteristics are assessed by employing relevant formulae. • Young's modulus, bulk modulus, shear modulus, longitudinal modulus, and Poisson's ratio are derived using both Bond compression and Makishima–Mackenzie models. For B 2 O 3 -Bi 2 O 3 -BaO glass system, γ , proton, alpha, electron, and neutron radiation shielding aspects were examined. Adopting Phy-X/PSD software, mass attenuation coefficients (μ / ρ) have been derived, and such μ/ρ quantities are in good unanimity with evaluated FLUKA, Geant4, and MCNPX codes corresponding μ/ρ end products. Equivalent atomic number and up to 40 mfp 'buildup factors' (utilizing G–P fitting procedure) were reckoned at ten distinct penetration depths. Deduced radiation protection efficiency values validated all glasses' laudable absorption potential for the minimal energy photons. At 15–15 × 103 KeV kinetic energy range, alpha particle and proton mass stopping powers and projected ranges by SRIM code including electron mass stopping power using ESTAR database were evaluated. For fast neutrons, the calculated macroscopic effective removal cross-section (Σ R) reveals that 25B 2 O 3 -70Bi 2 O 3 -5BaO (mol%) sample owns proportionately larger Σ R (=0.1206 cm–1). 70B 2 O 3 -15Bi 2 O 3 -15BaO (mol%) glass exhibits the largest total cross-section for thermal neutron absorption. Further, various physical features and elastic (Young's, bulk, shear, and longitudinal) moduli and Poisson's ratio values were derived for all samples. Both BC (bond compression) and M-M (Makishima–Mackenzie) models have been utilized for elastic aspects evaluation, and such features are altered considerably with Bi 2 O 3 increment in the studied glasses. By BC and M-M models, obtained Poisson's ratio is varied at 0.2434 – 0.2749 and 0.2384 – 0.2826 ranges respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • Physical and mechanical aspects and nuclear radiation attenuation features are investigated for gallium bismuth borate glasses. • Young's modulus, bulk modulus, shear modulus, longitudinal modulus, and Poisson's ratio are deduced using the bond compression model. • Related theoretical approaches and computational methods are utilized to derive shielding factors. • 25B 2 O 3 -65Bi 2 O 3 -10Ga 2 O 3 (mol%) glass shows superior gamma-ray shielding capacity. • 65B 2 O 3 -25Bi 2 O 3 -10Ga 2 O 3 (mol%) glass exhibits better ability for thermal neutrons absorption. For five Ga 2 O 3 -Bi 2 O 3 -B 2 O 3 composition glasses for improved Bi 2 O 3 content at 25 to 65 mol% (10% continuously each time) at a fixed 10 mol% Ga 2 O 3 amount, distinct physical and mechanical aspects and nuclear radiation attenuation factors were investigated. Increased Λ (optical basicity) values with a gradual Bi 2 O 3 addition indicate studied samples' improving basic character. Applying BC (bond compression) model key mechanical traits such as Y bc (Young's modulus), K bc (bulk modulus), S (shear modulus), L (longitudinal modulus), and σ (Poisson's ratio) are evaluated where in all glasses 10Ga 2 O 3 -65Bi 2 O 3 -25B 2 O 3 (mol%) sample exhibits superior elastic moduli. Enhanced Bi 2 O 3 causes for compactness of the gallium borate network as ǹ c (average cross-link density) improves from 2.3 to 3.4 indicating increased rigidity of glasses. Later, PHITS, FLUKA, and MCNPX codes are wielded to derive μ/ρ (mass attenuation coefficient) of all selected samples for photons having energy ranging from 15 KeV to 15 MeV. Simulated μ/ρ quantities exactitude is tested via Phy-X/PSD and WinXCOM programs' μ/ρ results and identified a fairly good harmony among them. With photon energy, MFP (mean free path), TVL (tenth-value layer), and HVL (half-value layer) values variations show a similar tendency and against the trend which noticed for μ/ρ and μ (linear attenuation coefficient) values. 10Ga 2 O 3 -65Bi 2 O 3 -25B 2 O 3 (mol%) sample's MFP and HVL are correlated with five commercial γ -ray glass shields' respective values at 1.25 MeV, 0.662 MeV (137Cs), and 0.2 MeV energies. Further, Z eq (equivalent atomic number) and using G–P (geometric progression) fitting approach for ten individual PDs (penetration depths) within 1–40 mfp range at 15 – 15 × 103 KeV energy region BUFs (buildup factors) were estimated. Attained RPE (radiation protection efficiency) findings attest all chosen Ga 2 O 3 -Bi 2 O 3 -B 2 O 3 glasses' competent absorption capacity for lower energy photons. Next, α -particles and protons MSPs (mass stopping powers), i.e. Ψ A and Ψ P and PRs (projected ranges), i.e. Φ A and Φ P by utilizing SRIM code as well as for electrons MSPs (Ψ E) and CSDA (continuous slowing‐down approximation) ranges by ESTAR database have been calculated within 15–15 × 103 KeV KE (kinetic energy) range. Also, Σ R (fast neutron removal cross-section) and for 0.253 × 10–4 KeV energy neutrons σ T (total cross-section) and SP (shielding percentage) values were approximated. With Bi 2 O 3 addition, realized Σ R is changed at 0.1161–0.1213 cm−1 extent. For thermal neutrons absorption, 10Ga 2 O 3 -25Bi 2 O 3 -65B 2 O 3 (mol%) glass shows larger σ T (=17.534 cm−1) and at any considered thickness higher SP whereas 10Ga 2 O 3 -65Bi 2 O 3 -25B 2 O 3 (mol%) (lead-free) glass has better attenuating features for photons affirming the incorporated Bi 2 O 3 favorable effect. [ABSTRACT FROM AUTHOR]

In this study, nearly 84 marine sediment samples were collected from twelve points in four cities (Quseir, Safaga, Hurghada, and Ras Gharib) along the Egyptian Red Sea sectors. The collected samples were extensively examined to estimate the natural radioactivity level. The obtained results were compared to the reported ranges from other locations in different countries. Hazardous radiation parameters such as radium equivalent, annual dose, and external hazards were estimated and compared to United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) recommended levels. The values were recorded in the first natural radioactivity database of coastal sediments from Egyptian Red Sea cities. The dose rate for certain organs was evaluated. The results showed that Red Sea beach sediments are safe in terms of natural radioactivity. It can be concluded that they do not pose a risk to tourists going to the beaches for recreation or to sailors and fishers involved in economic activities along the Egyptian Red Sea coast. • Marine sediment samples were collected along the Egyptian Red Sea sectors with extensively examined to estimate NORM. • The obtained results were compared to the reported ranges from other locations in different countries. • Hazardous radiation parameters such as Raeq, AEDE, Hex,in were estimated and compared to UNSCEAR recommended levels. • The results showed that Red Sea beach sediments are safe in terms of natural radioactivity. • They do not pose a risk to tourists going to the beaches for recreation. • or to sailors and fishers involved in economic activities along the Egyptian Red Sea coast. [ABSTRACT FROM AUTHOR]

• This study investigates the effectiveness of novel nanocomposite shielding materials in reducing out-of-field radiation doses during radiation therapy. • The research employs detailed simulations of a clinical linear accelerator and a mesh-type human phantom to estimate out-of-field organ doses. • Results demonstrated that nanocomposites made of PTFE with PtO 2 , IrO 2 , and Bi 2 O 3 nanoparticles significantly reduce radiation exposure to non-target tissues. This study investigates the effectiveness of novel nanocomposite shielding materials in reducing out-of-field radiation doses during radiation therapy, employing Geant4 Monte Carlo (MC) simulations alongside an anthropomorphic female phantom. The research focuses on two radiation modalities: 6 MV beams with and without flattening filters. Utilizing the Geant4 MC code, detailed simulations of a Varian Clinac 2100C/D linear accelerator and an ICRP-145 mesh-type human phantom were conducted to estimate the doses to out-of-field organs from unintended secondary radiation. This involved simulating a comprehensive linac model, including all relevant beam-line components, and assessing the shielding effects of three different nanocomposites doped with metal nanoparticles at various thicknesses. The nanocomposites, comprising Polytetrafluoroethylene (PTFE), with PtO 2 , IrO 2 , and Bi 2 O 3 nanoparticles, were evaluated for their potential to reduce patient organ doses from stray photon doses. The results showed that these materials could significantly lower radiation exposure to non-target tissues. [ABSTRACT FROM AUTHOR]

This study examines the radiation shielding properties of sixteen diverse concrete types encompassing both gamma-ray and neutron radiation. Concrete, a widely used material due to its low cost, high density, and efficient shielding capabilities, is investigated to determine how its varying compositions impact its ability to attenuate ionizing radiation. Utilizing the Phy-X/PSD software, the research analyses key parameters like mass attenuation coefficients, linear attenuation coefficients, and half-value layers, among others, to assess each concrete type's shielding efficiency. The findings reveal that concretes containing heavy metals such as iron and barium exhibit enhanced performance in absorbing photons, thus providing superior protection against radiation. Iron-Portland concrete demonstrated a high density of 5.80 g/cm³ and exhibited a mass attenuation coefficient (MAC) of 35.14 cm2/g at 0.1 MeV, significantly higher than MAC of ordinary concrete (i.e., 17.24 cm2/g). Significantly, Iron-Portland and Barite Concrete are highlighted for their exceptional shielding abilities, with Iron-Portland showing a fast neutron removal cross-section (Σ R) of 14.29 cm−1, compared to 11.11 cm−1 for ordinary concrete. It can be concluded that the high elemental mass fraction of iron (88.12 wt%) in Iron-Portland concrete, along with its significant density of 5.80 g/cm3, makes it the most advantageous for gamma-ray and neutron shielding applications due to its superior absorption and attenuation capabilities. • Iron and Barium in concrete significantly enhance radiation shielding. • Iron-Portland concrete shows exceptional performance at high-energy levels. • Diverse concrete densities directly influence radiation attenuation efficiency. • Barite Concrete (Type BA) maintains effectiveness across energy spectra. • Material composition critical for optimizing concrete's shielding capabilities. [ABSTRACT FROM AUTHOR]

Many oxide additives have historically been used to enhance the radiation shielding properties of glasses, yet the potential of high-entropy oxides (HEOs), which have gained popularity in material science for their unique properties, has not been explored in this context. This study is the first to investigate the radiation shielding capabilities of Zinc-Tellurite glass infused with High Entropy Oxide (HEO), specifically utilizing the novel attributes of a synthesized TiZrNbHfTa. In this study, the nuclear shielding properties of newly fabricated Zinc-Tellurite glasses doped with TiZrNbHfTaO x with a composition (25ZnO·75TeO 2)100-x. (TiZrNbHfTaO x)x (x = 0, 1, 2, 3, 4 mol%) were studied. Through the synthesis of a TiZrNbHfTa HEA and its integration into glass structure, we have developed a series of novel materials with enhanced protective properties against both gamma-ray and neutron radiation. Experimental results demonstrate that the HEO-infused glass, particularly the HEC1-4 composition, significantly surpasses traditional shielding materials in neutron attenuation, evidenced by its superior effective neutron removal cross-section. Additionally, the HEC1-4 glass demonstrates improved gamma-ray shielding capabilities, with increased mass attenuation coefficients and decreased half-value layers, indicating a higher capacity for photon interaction and absorption. It can be concluded that the incorporation of High Entropy Alloys into glass matrices not only opens a new frontier in radiation shielding materials but also provides a versatile and effective solution with considerable potential for enhancing safety measures in radiation-prone environments. [ABSTRACT FROM AUTHOR]

The current study is intended to examine the optical, structural and photon/neutron shielding qualities of a group of different ZrO 2 content doped 60B 2 O 3 +20Bi 2 O 3 +(20-x)Li 2 O + xZrO 2 glasses, labeled as BBLZ1, BBLZ2, BBLZ3, BBLZ4 and BBLZ5 manufactured via the melt quenching technique. The specific gravity of the glasses was boosted with increasing ZrO 2 additive and molar volume exhibited the opposite trend versus the density. XRD patterns were obtained to reveal the amorphous structure of the glasses. Spectra of optical absorption for BBLZ glasses were recorded in the wavelength region 200–1100 nm. The direct band gap (E g) values dropped from 4.24 to 3.87 eV with the boosting ZrO 2 content while the indirect E g s declined from 3.78 to 3.18 eV. The refractive index grew as the ZrO 2 substitution ratio enhanced. To determine photon shielding parameters of BBLZ glasses, the mass attenuation coefficients (MAC) were gained viz Py-MLBUF online program for the 0.015–15 MeV gamma ray energies. Several shielding parameters of BBLZ glasses such as Half Value Layer (HVL), Exposure Buildup Factor (EBF) and Mean Free Path (MFP) were reached using MAC values. The highest MACs differ from 68.188 cm2/g to 0.036 cm2/g for BBLZ5 glass while the lowest μ/ρ values varying from 69.413 cm2/g to 0.036 cm2/g belong to the BBLZ1 glass. The thinnest MFP and HVL values were observed in the BBLZ5 glass with the highest ZrO 2 contribution (4 mol %). Adding ZrO 2 to the fabricated glasses reduced photon buildup. BBLZ5 glass was determined to be the safest neutron shield due to its high density. It can be concluded that ZrO 2 addition with increasing rates to lithium bismo-borate glasses reinforced both optical properties and nuclear radiation security qualities. • A novel B 2 O 3 –Bi 2 O 3 –Li 2 O–ZrO 2 system has been fabricated. • Amorphous structure of the glasses were verified by XRD measurements. • Spectra of optical absorption for BBLZ glasses were recorded and optical parameters were calculated. • Nuclear shielding characterization of fabricated glasses was studied. • BBLZ5 glass sample with highest ZrO 2 contribution has excellent optical and nuclear radiation shielding properties. [ABSTRACT FROM AUTHOR]

[Display omitted] • • Nuclear radiation shielding aspects and mechanical features are evaluated for ten lithium bismuth borate glasses. • • Pertinent theoretical methods and computational approaches are employed to deduce shielding parameters. • • 35B 2 O 3 -55Bi 2 O 3 -10Li 2 O (mol%) glass exhibits better gamma-ray attenuation ability. • • 70B 2 O 3 -10Bi 2 O 3 -20Li 2 O (mol%) glass shows superior efficacy for thermal neutrons absorption. • • Young's modulus, bulk modulus, shear modulus, longitudinal modulus, and Poisson's ratio are derived theoretically. Against photon energies extending from 0.015 to 15 MeV, MCNPX, FLUKA and PHITS codes are operated to simulate mass attenuation coefficients (μ / ρ) for a total of ten B 2 O 3 -Bi 2 O 3 -Li 2 O glass compositions with added Bi 2 O 3 amount from 10 to 55 mol% (5 mol% growth gradually) as a substitute for total (B 2 O 3 + Li 2 O) mol% content. All the computed μ/ρ values correctness is examined by Py-MLBUF and WinXCOM programs' μ/ρ outcomes and we found a good agreement among them. 55Bi 2 O 3 -35B 2 O 3 -10Li 2 O (mol%) glass half-value layer (HVL) and mean free path (MFP) quantities are compared with distinct commercial γ -ray attenuating glasses, alloys, polymers, concretes and lead and ceramics corresponding values. Next, equivalent atomic numbers (Z eq) and by employing geometric progression (G – P) fitting method at 1–40 mfp PDs (penetration depths), at 0.015–15 MeV energy range 'buildup factors' were calculated. At all chosen twenty-five energies derived radiation protection efficiency (RPE) results assured investigated samples exemplary competence for low energy photons absorption. Applying SRIM codes Ψ P and Φ P and Ψ A and Φ A (mass stopping powers (MSPs) and projected ranges (PRs) for protons and α -particles), and making use of ESTAR database Ψ E (electron MSP) and continuous slowing‐down approximation (CSDA) range for electrons are determined at KE (kinetic energy) range of 0.015–15 MeV. Moreover, fast neutron removal cross-sections (Σ R), for 0.0253 eV energy neutrons absorption cross-sections have been estimated. Deduced Σ R was altered at 0.1105–0.1205 cm−1 range with Bi 2 O 3 inclusion in studied samples. 10Bi 2 O 3 -70B 2 O 3 -20Li 2 O (mol%) glass has greater total cross-section (=23.251 cm−1) for thermal neutrons absorption while 55Bi 2 O 3 -35B 2 O 3 -10Li 2 O (mol%) sample exhibits quality shielding factors for photons and fast neutrons confirming the included Bi 2 O 3 positive impact. Along with nuclear attenuation features various physical and mechanical aspects are also inspected. Derived V m (molar volume), OPD (oxygen packing density), V o (oxygen molar volume), V t (packing density) and G t (dissociation energy per unit volume) values indicated glasses rigidity. Following Makishima–Mackenzie's theoretical model primary mechanical features like Y, K, S and L (Young's, bulk, shear and longitudinal modulus) and σ (Poisson's ratio) are evaluated where 10Bi 2 O 3 -70B 2 O 3 -20Li 2 O (mol%) glass shows better elastic moduli in all samples. [ABSTRACT FROM AUTHOR]