The noted Design of a new and effective radiation shielding material is a growing demand to reduce the harmful effects of ionizing radiation in medical and nuclear applications. In this research ...article, three silver nitrate (AgNO
3
) doped PVA polymers were reported to serve as potential shielding materials against gamma ray. These polymers were tested in terms of their polarizability, optical transmission, and metallization properties. Furthermore, the radiation shielding performance of the involved polymers was assessed by Geant4 simulations based on Monte Carlo approach over a large range of energies up to 15 MeV. The results indicate that the density of the present polymers increased from 1.19 g/cm
3
for pure-PVA to 1.41 g/cm
3
for 5% AgNO
3
doped PVA sample. At high energies, exceeding 150 keV, LAC values of all investigated samples become almost independent of their chemical composition. For Pure-PVA polymer, the LAC values start from its highest values of 1.358 cm
−1
at 15 keV then decrease with increasing energy to be 0.022 cm
−1
at 15 MeV. At all penetration depths and energies, EABF values were higher for Pure-PVA than those of other polymers. The AgNO
3
addition has a positive impact to improve the shielding performance of the polymer to be close to that of ordinary concrete (standard radiation shield).
Tb
3+
-doped sodium-silicate glasses, chemically defined as (73.2SiO
2
-15.3Na
2
O-6MgO-2ZnO- 3.5CaO)
1-x
-(TbF
3
)
x
for x = 0, 5, 7, 9, 11, 13, and 15 wt%) were theoretically investigated for their ...radiation shielding and dosimetry potentials. The photon interaction parameters were estimated using the NIST-XCOM computational tool. The obtained results showed that the attenuation coefficient of the sodium-silicate glasses decreased from 7.2062 to 0.0210 cm
2
/g for x = 0, 10.5553 to 0.0221 cm
2
/g for x = 5 mol%, 11.8949 to 0.0225-cm
2
/g for x = 7 mol%,, 13.2346 to 0.0229cm
2
/g for x = 9 mol%, 14.5742 to 0.0233 cm
2
/g for x = 11 mol%, 15.9138 to 0.0238 cm
2
/g for x = 13 mol%, and 17.2534 to 0.0242 cm
2
/g for the x = 15 mol% sample, respectively, for γ-photon energy increase from 15 to 15,000 keV. For the same sample order, the mass energy absorption coefficient varied from 0.0161 to 7.4884, 0.0167 to 10.5009, 0.0169 to 11.7058, 0.0171 to 12.9108, 0.0174 to 14.1158, 0.0176 to 15.3208, and 0.0176 to 16.52582 cm
2
/g. The effective atomic number changed from 10.49 to 24.04, 10.62 to 27.69, 10.74 to 30.84, 10.87 to 33.57, 11.01 to 35.97, 11.15 to 38.10 for SNMZCT2, SNMZCT3, SNMZCT4, SNMZCT5, SNMZCT6, SNMZCT7, respectively. The minimum specific gamma constants for the investigated samples were obtained at 0.2 MeV with values of 5.435 Rm
2
/Cih, 6.102 Rm
2
/Cih, 6.770 Rm
2
/Cih, 7.437 Rm
2
/Cih and 8.772 Rm
2
/Cih for SNMZCT2, SNMZCT3, SNMZCT4, SNMZCT5, SNMZCT6 and SNMZCT7, respectively. Using the geometric fitting method, the computed buildup factors show significant variation with energy of incident gamma photons, number of glass mean free path (mfp), and the chemical composition (i.e., TbF
3
content) of the glasses. Increasing the molar concentration of TbF
3
in the glass system improves its photon shielding abilities and suppresses photon scattering in the glasses.
2D nanomaterial phosphorene is a chemistically stable, biocompatible, and biodegradable drug delivery platform. This study investigates the drug loading efficiency of phosphorene for the ...cardiovascular drug carvedilol using density-functional theory (DFT). In the gas phase, carvedilol prefers to interact with phosphorene via P-H bonding with an adsorption energy of 0.59 eV (0.45 eV in water). The complex HOMO-LUMO energy gap has been calculated in gas and solvent media to assess phosphorene-carvedilol reactivity. As compared to free carvedilol and phosphorene, the phosphorene-carvedilol complex has increased solubility. The NCI analysis visualises non-covalent interactions within complexes. The low Van der Waals interactions between carvedilol and phosphorene allow for easy drug offloading. The phosphorene-carvedilol complex is more soluble in water than previously thought. Phosphorene's electron density changes significantly after complex formation, as revealed by charge decomposition plots and electron-localization function plots. PET (photo-induced electron transfer) analysis explains quenching.
Simultaneous sampling collection of suspended particulate matter (SPM) and fine aerosol particles with an aerodynamic diameter equal or less than 2.5 μm (PM
2.5
) from industrial and residential ...areas of Greater Cairo, Egypt, has been carried out during two different seasons namely autumn 2014 and winter 2014/2015. The average mass concentrations of both SPM and PM
2.5
samples are higher than the annual mean levels, especially for the samples collected from the industrial area. In addition, the mass concentrations of SPM are much higher than the PM
2.5
mass concentrations during the whole sampling period. The ratios of the mass concentration between the SPM and PM
2.5
were determined to be equal to 20 ± 6 and 17 ± 4 for the residential and industrial areas, respectively, and these ratios seem to be constant during the two mentioned seasons. Based on our previous elemental analysis results using multiple secondary target energy dispersive X-ray fluorescence (EDXRF), 18 elements in both SPM and PM
2.5
samples have been quantified. Remarkable variations in the elemental concentrations between the SPM and PM
2.5
samples were obtained. Comparison and statistical analysis of the elemental composition of both SPM and PM
2.5
have been investigated. The PMF model EPA 5.0 was utilized for source identification on both PM fractions. Seven sources were identified and their relative contributions in the two areas of the study were investigated.
Optoelectronic and thermoelectric properties of A
3
InAs
3
(A = Sr and Eu) Zintl compounds are investigated using FP-LAPW method with LDA, GGA and mBJ potentials for Sr
3
InAs
3
in addition with ...Hubbard (U) for Eu
3
InAs
3
based on DFT. Electronic properties reveal that both the compounds are direct bandgap semiconductors and their semiconducting nature is also supported by electrical resistivity (conductivity). The direct bandgap value is ranging from 0.50 to 0.74 and is decreasing with the replacement of Sr by Eu. The results divulge that both the compounds are optically active in the infrared region and optically anisotropic in nature and can be used as a shield for ultraviolet radiation and potential candidate for optoelectronic devices. Negative value of -383 and -411 µV/K Seebeck coefficients suggest that electrons are the majority charge carriers. Low thermal conductivity, high Seebeck coefficient and high power factor indicating that A
3
InAs
3
(A = Sr and Eu) are the potential matrix for thermoelectric application.
Electrochemical water splitting is a well-sought method for the production of renewable energy due to its low cost, high efficiency, ease of operation, availability of a variety of catalysts, and ...green approach. In this research, an amine-functionalized Ce-MOF loaded on nickel foam (NF) presented as Ce-MOF-NH
2
/NF electrocatalyst is prepared by a simple hydrothermal method. Prepared material is characterized by X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and atomic force microscopy (AFM) to confirm morphological and structural properties. The synthesized catalyst is used for electrochemical OER in a 1M KOH solution. Ce-MOF-NH
2
/NF demonstrated onset potential, Tafel slope, and overpotential of 1.49 V, 69 mV/dec, and 328 mV, respectively. For comparison, Ce-MOF is also prepared and employed for OER under the same conditions and it exhibited onset potential, Tafel slope, and overpotential 1.5 V, 89 mV/dec, and 348 mV, indicating the superior performance of functionalized MOF. The obtained results reveal the promising overpotential of the Ce-MOF-NH
2
/NF -based electrocatalyst for green energy production via electrochemical water splitting.
This research article aims to study the neutron and charged particle attenuation properties of volcanic rocks collected from the western region of Saudi Arabia. The rock samples labeled as VR1, VR2, ...VR3, and VR4 were experimentally investigated by a Field Emission Scanning Electron Microscope (FE-SEM) and Energy-Dispersive X-ray Spectroscopy (EDS). The neutron transmission factor (TF) was estimated by using the Monte Carlo technique for different thicknesses varying from 0 to 3 mm. Moreover, we studied the charged particles' interaction properties with the present volcanic rocks for projectile energy up to 2.5 MeV. The obtained results reveal that the neutron TF decreased from 95.2, 95.8, 94.9, and 95.3 % at 0.5 mm to 74.4, 77.4, 73.4, and 75.1 % at 3 mm for the rock samples of VR1, VR2, VR3, and VR4, respectively. We found that the maximum projectile range (ℜ) occurred at the low energy region (0.2 MeV) for charged particle interactions. In comparison, the minimum ℜ occurred at the high energy level (2.5 MeV). Additionally, the values of ℜ come in the order of ℜ electron > ℜ proton > ℜ alpha > ℜ carbon with the minimum values of 185.6, 221.8, 178.8, and 189.8 μm in the case of the electron, and with the values of 0.696, 0.8141, 0.669, and 0.716 μm in the case of carbon ion for VR1, VR2, VR3, and VR4, respectively. This result revealed the VR3 rock sample as a superior shielding material against neutron beams and charged particles among the studied volcanic rocks.
•Four volcanic rocks were collected, prepared, and studied as radiation shields.•Energy-Dispersive X-ray Spectroscopy (EDS) was applied for the rock samples.•The neutron shielding ability is examined by using Geant4 simulations.•The highest neutron transmission factor was observed for VR3 rock sample.•VR3 rock sample has a superior shielding ability against neutrons beam and charged particles.
A quaternary glass system described by the composition 35Pb3O4–60SiO2–(5-x)ZnO–xWO3 (0 ≤ x ≤ 5 mol%) was prepared via the ordinary method namely melt quenching. The amorphous state of this system was ...experimentally evaluated using X-ray diffraction. At room temperature, Fourier-transform infrared (FTIR) spectroscopy was carried out to test the structure of each specimen by using the KBr technique for wavenumber of 4000–400 cm−1. The FTIR test demonstrated that structural units and connectivity of the modifier oxide tetrahedral increased, whereas non-bridging oxygen decreased as ZnO was substituted by WO3. The results of neutron transmission studies showed that 6 mm was the required thickness to reduce by half the intensity of the fast neutron beam; more specifically, the fast neutron transmission factor was 0.54, 0.53, 0.53, 0.51, and 0.49 for the prepared glass specimens G1, G2, G3, G4, and G5, respectively. For charged particles, the maximum range was observed in the high energy region (10 MeV) for all projectiles studied, with 8066.33 μm for electrons, 356.86 μm for protons, 39.30 μm for alpha particles, and 5.83 μm for carbon ions. The prepared glass system has promising features for use in various dosimetry and radiation protection applications at a neutron energy below 10 MeV.
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