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The activity concentrations of the terrestrial naturally occurring radionuclides 214Pb, 214Bi (from 238U series), and 228Ac (from 232Th series) and 40K were measured in soil and rock samples obtained from three sites of the Russaifa mine and its surrounding in the Russaifa region using an HPGe-detector of 20 % relative efficiency. While the soil activity (in Bq/kg) was found to be: 408.63 ± 26, 383.9 ± 4.7, and 383.0 ± 4.0 for 238U, 214Bi, and 214Pb, respectively. The rock activity was found to be 225.4 ± 19, 180.36 ± 3.9, and 179.47 ± 3.1 for 238U, 214Bi, and 214Pb, respectively. Our results reveal that the average activity concentrations in the mine (site 1) are higher than worldwide average values [6] for 238U, 214Pb, and 214Bi. In contrast, the results show that the average absorbed dose rates in the other sites 2 and site 3 are lower than the world average for all radionuclides measured in this study. Also, the average activity concentrations in soil samples 238U, 214Pb, and 214Bi are higher than the average activity concentrations in rock samples in all sites. Furthermore, the average absorbed dose rate (in nGy h-1) was found to be 265.3 for 238U, 233.3 for 214Bi, and 13.3 for 214Pb, respectively, and the average absorbed dose rates for both 228Ac and 40K were below the minimum detectable activity (MDA). Moreover, the average annual effective dose rates in soil and rock samples were estimated. While it is found to be 366.90 µSv for 238U, 306.84 µSv for 214Bi, and 37.58 µSv for lead in soil samples, for the rock samples it is found to be 163.75 µSv for 238U, 105.83 µSv for 214Bi, 13.05 µSv for lead. However, the average annual effective dose rates for 214Bi and 40K in soil and rock samples are below the minimum detectable activity (MDA). The results display that the average outdoor annual effective doses for both 238U and 214Bi are higher than the world average and the average outdoor annual effective dose equivalents for the other radionuclides are lower than the world average. They also show that the average outdoor annual effective doses in soil samples for 238U, 214Pb, and 214Bi are higher than the average outdoor annual effective doses in rock samples. [ABSTRACT FROM AUTHOR]

This study explores the structural, radiation, and optical properties of cyclosilicates minerals (CMs), providing comprehensive analyses of molar volumes, densities, band gap values, and effective atomic numbers. The structural properties were found to be dependent on the correlations with the interatomic interactions derived from the analysis of Hirshfeld topological surfaces (HTSs) and their voids. In examining a broad energy spectrum from 0.015 to 15 MeV, the study focuses on mass attenuation coefficient (MAC) and linear mass attenuation coefficient (LAC). Results show that MAC values are the highest for the BaTi(SiO3)3 crystal, highlighting its superior γ‐ray attenuation capabilities among other CMs. The study finds that Hirshfeld volume, and surface ranged between 344.21 and 2640.98 Å3 and 388.91 and 1326.97 Å2, reveals distinct electron density distribution characteristics in CM materials. The study probes the impact of HTSs on structural (113 < Vm < 686 cm3/mol), optical (1.95 < n < 2.38), and radiation shielding (13.0 < LAC < 102.0 1/cm at E = 15.0 keV) values, demonstrating that altering the O...A (A = atom in the CM crystal) interactions align with the charge density, potentially tuning other physical values. [ABSTRACT FROM AUTHOR]

Understanding the behavior of SiO2 under different external conditions, particularly pressure, is essential for advancing its applications. While existing literature primarily focuses on the impact of isotropic stress on SiO2, there remains a gap in exploring the effects of uniaxial and biaxial stresses on its properties. This study aims to address this gap by investigating the novel effects of uniaxial, biaxial, and isotropic pressures on the opto-electrical properties of SiO2 using first principles calculations. Our results reveal distinct structural adaptations of SiO2 under different pressure conditions, demonstrating its anisotropic behavior. For example, under isotropic pressure in the interval [0.0, 12.5] GPa, the lattice parameters 5.039 < a < 4.615 Å, and 5.529 < c < 5.239 Å, and the unit cell volume ranged from 121.57 to 96.65 Å3 show reductions in values, indicating structural compression in accordance with the experimentally found values. Additionally, we investigated the electrical properties, including the complex dielectric function and conductivity. At an isotropic pressure of 0 GPa, the real refractive index of SiO2 is approximately n = 2.04083, which increases to n = 2.20836 at 12.5 GPa, while applying uniaxial or biaxial pressure resulted in direction-dependent-refractive index highlighting the crystal's anisotropic to external pressure. Also, our study revealed that the maximum values of conductivity increased while wavelength shift decreased as a function of the applied stress on the crystal. These findings provide valuable insights into the behavior of SiO2 single crystal under directional stresses, facilitating the design of pressure-sensitive optoelectronic devices. [ABSTRACT FROM AUTHOR]

The radiation, elastic-mechanic-characteristics of LMAS (Li2O-MgO-Al2O3-SiO2) glass systems influenced by the molar ratio [SiO2]/([P2O5] + [Al2O3]) additions were investigated. Within the incoming photon energies: 0.015 to 15.0 MeV spanned in this study, both XCOM and Phy-X/PSD codes were utilized. The outcomes demonstrate that substituting P2O5 with Al2O3 at the expense of SiO2 led to an increase in glass density from 3.021 to 3.26 g/cm3, which, in turn, decreased the LAC from 2.633 to 2.534 cm−1 at E = 400 keV. The MAC values were found to be 6.721 < MAC < 7.004 g/cm2 at low photon energy.The uppermost values of MAC were observed for the glass-system encoded as 0P-5AF with a direct relationship to energy. The highest effective-atomic-number (Zeff) was recorded at E = 20 keV, and ranged from 18.13 to 19.31 for the LMAS samples. Subsequently, Zeff declined rapidly to a value around 9.75 at E = 1.0 MeV, and slightly increased above E = 1.50 MeV. Furthermore, the tenth-value-layer (TVL) values bare that an decrease of [SiO2]/([P2O5] + [Al2O3]) mol% from 0.0 to 20.8% decreased the thickness required to stop or obstruct photons (e.g., 11.974 < TVL < 11.241 cm at E = 1.0 MeV). The 3P-5A sample exhibited the highest half-value-layer 0.033 < HVL < 10.666 cm, while the 2P-16A sample had the lowest HVL. The optimized ratio [SiO2]/([P2O5] + [Al2O3]) was found to be 6.8.The radiation shield hallmarks of the LMAS glass blocks developed as the ratio [SiO2]/([P2O5] + [Al2O3]) enhanced in the glass samples. The elastic moduli were found to depend on this ratio content molar concentration. Accordingly, the radiation shielding properties are also correlated in same manner. Also, the calculated elastic-mechanical intrinsic of these transparent blocks, include the molar volume (Vm), which increased from 18.157 to 19.92 cm3/mol, and the free-energy (G) from 71.895 to 83.313 kJ/cm3 were found to depend on the nominated mol%. [ABSTRACT FROM AUTHOR]

The role of the [Na2O]/[CuO] ratio in two glass groups with a chemical formula of (50 − y/2)Na2O–yCuO–(50 − y/2) P2O5 (y = 0.0–40 mol%) coded as Line I and (50 − y)Na2O–yCuO–50P2O5 (y = 0.0–50 mol%) coded as Line II on physical and gamma-ray attenuation properties have been deeply investigated. The density (ρ) varied from 2.471 to 3.262 g/cm3 and from 2.471 to 3.113 g/cm3 for Line I and Line II glasses, respectively. The molar volume (Vm) values varied from 41.280 to 28.526 cm3/mol and from 41.280 to 35.609 cm3/mol for Line I and Line II glasses, respectively. The oxygen molar volume (OMV) reduced from 13.761 to12.972 cm3/mol and from 13.761 to 11.873 cm3/mol, while the oxygen packing density (OPD) improved from 72.674 to 77.124 and from 72.674 to 84.253 g.atom/l for Line I and Line II glasses. The mass and linear attenuation coefficients (MAC and LAC) values corresponding to the Line II glass is slightly lower than their counterpart of the Line I. The effective atomic numbers (Zeff) and electron density (Neff) for glasses in Line I was lower than that for those in Line II. Exposure (EBF) and energy absorption (EABF) buildup factors have the same trend in both glass groups. The findings support the capability to utilize the examined glasses as radiation shielding materials. [ABSTRACT FROM AUTHOR]

The desired target of the current report was to examine the efficiency of MnO-based glass systems against x- or g-rays, and mechanical properties with varying amounts of MnO incorporation. The focus was on evaluating their radiation shielding performance and determining their elasto-mechanic intrinsic characteristics. Various gamma and neutron shielding factors, including HVL (half-value layer), Zeff (Zeff: effective atomic number), Zeq (equivalent atomic number), EBF (exposure buildup factor), EABF (energy absorption buildup factor), ACS (atomic cross-section), ESC (electronic cross-section), and SAFE* (specific absorbed fraction of energy) were planned to assess the radio-protection capabilities of the probed glass systems. Exemplified at E = 15 keV, the MAC (mass attenuation coefficient) values are: 13.99 cm2/g, 14.03 cm2/g, 14.18 cm2/g, 14.36 cm2/g, and 14.55 cm2/g for the glass blocks encoded as LZBP, 0.1Mn:LZBP, 0.5Mn:LZBP, 1.0Mn:LZBP, and 1.5Mn:LZBP respectively, while the SAFE values vary between 31907 g−1 and 32013 g−1 as Mn2+ is increased from 0.0 mol% to 1.5 mol%. The outcomes indicate that as the manganese (II) oxide mol% increases, then the MAC, Zeff, Zeq, ACS, and ESC values also increase. Among the samples, 1.5Mn:LZBP exhibited the least HVL, EBF, EABF, and SAFE values. This glass, which contains 1.5 mol% of MnO and has the highest interconnecting bonding/volume, may be deemed as an advanced glass for ray protection in the different fields, providing valuable insights into their radiation shielding performance. [ABSTRACT FROM AUTHOR]

The concentrations of elements in pharmaceuticals derived from plant seeds were determined by energy dispersive X-ray fluorescence. The concentrations of Ca, Si, Cl, K, S, Ti, Cr, Mn, Fe, P, Cu, Zn, Br, Rb, Sr, Hg, and Zr were quantified; only Si (10 ± 1 to 70,000 ± 110 mg kg−1), S (10 ± 2 to 12,4000 ± 243 mg kg−1), K (4,000 ± 58 to 24,000 ± 70 mg kg−1), Ca (2200 ± 35 to 87,000 ± 150 mg kg−1), Mn (21 ± 4 to 1956 ± 17 mg kg−1), and Fe (100 ± 7 to 5150 ± 70 mg kg−1) were present in all samples. These results may validate the use of these pharmaceuticals for the treatment of disease due to high concentrations of essential elements Mn, Ca, Mn, K, Mg, Zn, Cl, Fe, and P. Mercury was present in some products below standard values. The results also have quality control applications because of the widespread use of these pharmaceuticals. [ABSTRACT FROM PUBLISHER]