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Öğe Delving into the properties of nanostructured Mg ferrite and PEG composites: A comparative study on structure, electrical conductivity, and dielectric relaxation(Cell Press, 2023) El-Ghazzawy, Enas H.; Zakaly, Hesham M. H.; Alrowaily, Albandari W.; Saafan, Samia A.; Ene, Antoaneta; Abo-aita, Nagat M.; Darwish, Moustafa A.Magnesium ferrite (MgFe2O4) and polyethylene glycol (PEG) are materials known for their versatility in various applications. This study presents a comprehensive comparative analysis of the electrical conductivity and dielectric relaxation of nanostructured MgFe2O4 and its composites with PEG. Through experimentation, it was observed that incorporating PEG into MgFe2O4 did not lead to a high relative observed decrease or increase in electrical conductivity at room temperature. The study revealed that the composites maintained stable electrical behavior at room temperature, with a dielectric constant value of around 9 and a loss tangent value of around 0.1 at high frequency (around 7 MHz). The electron-hole hopping mechanism was identified as the underlying cause for the strong dielectric dispersion with frequency. The low dielectric loss and conductivity of the MgFe2O4 and PEG/ferrite composites make them promising candidates for high-frequency switching applications and microelectronic devices, particularly in scenarios where negligible eddy currents are essential. Additionally, complex impedance data analysis demonstrated that the capacitive and resistive properties of the composites are primarily attributed to grain boundary processes. This study provides a comprehensive analysis of the electrical and dielectric properties of MgFe2O4 and PEG composites and highlights their potential for many applications in materials science, particularly in electrical and electronic devices.Öğe Dual Impacts of Bi2O3/B2O3 Substitution on Mechanical and Attenuation Properties of Zinc-Bismuth-Borate Ternary Glasses for Diagnosis ?-Rays Shielding Materials Application(Springer, 2023) Zakaly, Hesham M. H.; Tekin, H. O.; Issa, A. M. Shams; Alrowaily, Albandari W.; Ene, Antoaneta; Rammah, Y. S.Investigations have been made on the mechanical and gamma-ray attenuation properties of the zinc bismuth-borate ternary glass system with the chemical formula (70-x)Bi2O3-xB(2)O(3)-30ZnO, where x = 20 (S1), 25 (S2), 30 (S3), 40 (S4), 45 (S5), and 50 (S6) mol%. Makishima-Mackenzie model and Phy-X/PSD software were used to accomplish this goal. Our research showed that the packing density (Vt) and dissociation energy (Gt) values reduced from S1 glass sample (with B2O3 = 20 mol% and Bi2O3 = 50 mol%) to S6 glass sample (with B2O3 = 50 mol% and Bi2O3 = 20 mol%), respectively, from 0.522 to 0.352 and from 31.53 kJ/cm(3) to 26.97 kJ/cm(3). By increasing the amount of B2O3 in the glasses, the efficiency of their mechanical features was reduced. The S1 glass sample's linear (mu) and mass attenuation (mu(m)) coefficients had the highest values among the glass materials examined, i.e., (mu, mu(m))(S6) < (mu, mu(m))(S5) < (mu, mu(m))(S4) < (mu, mu(m))(S3) < (mu, mu(m))(S2) < (mu, mu(m))(S1). The S1 glass sample exhibits the lowest values for half value layer (T-0.5) and mean free path (lambda) of all the examined glasses. Consequently, (T-0.5, lambda )(S6) > (T-0.5, lambda )(S5) > (T-0.5, lambda )(S4) > (T-0.5, lambda )(S3) > (T-0.5, lambda )(S2) > (T-0.5, lambda )(S1). The analyzed glasses' effective atomic numbers (Z(eff)) follow the same trend for mass and linear attenuation coefficients. Our results show that the values of exposure (EBF) and energy absorption (EABF) accumulation factors decreased with increasing Bi2O3 and lowering B2O3 reinforcement for all mean free path values (i.e., from 0.5 to 40 mfp). Results show that of all the glasses under study, the S1 glass sample has the best gamma-ray shielding properties.Öğe Effects of WO3 reinforcement on the properties of poly(lactic acid) composites for radiation shielding(Pergamon-Elsevier Science Ltd, 2023) Issa, Shams A. M.; Alrowaily, Albandari W.; Abulyazied, D. E.; Ali, E. S.; Zakaly, Hesham M. H.During this work, efforts have been made to improve the gamma radiation shielding capabilities of poly(lactic acid) (PLA) by including tungsten trioxide (WO3). Simulations and theoretical analyses have been performed on the parameters of radiation shielding. They have been tested across a broad spectrum of energies, from 0.015 to 15 MeV. The values suggest that naturally occurring composites with a high WO3 content may be utilized to improve the gamma shielding properties of PLA/TO (TO & EQUIV;tungsten trioxide) composites for protection applications; such composites can be employed as a covering for the solar cells to prevent damage. The composite samples made of PLA and WO3 were analyzed for a range of photon energies. The results showed rise of considerable proportions in the values of linear attenuation coefficient (& mu;) and mass attenuation coefficient & mu;m at 0.08 MeV, due to the k-absorption edge of tungsten. In addition, & mu; and & mu;m for all samples at selected photon energy are increase as the WO3 content increases and decreases with increasing photon energy. The half value layer (T0.5) decreased as the WO3 content increased, with the highest values seen at 15 MeV and the lowest values at 15 keV. The behavior of the mean free path (& lambda;) was identical to T0.5 with regards to the amount of WO3 and the energy of the photon. The T0.5 values of the PLA-W7 were lower than other polymer materials, making it a more efficient material for filtering radiation. The Zeff values of the PLA/TO composite samples were the highest at 0.08 MeV and showed a trend of increasing with energy to 15 MeV. The exposure buildup factor (EBF) and energy absorption buildup factor EABF values were computed using the G-P fitting method and showed that the lowest values were presented for the PLA-W7. An increase in WO3 reinforcement in the PLA sample contributed to the decreased EBF-EABF values. The shielding parameters were determined through calculations done using both Phy-X/PSD and FLUKA, and the results from both are in good agreement with each other. The results of the study demonstrate the effectiveness of PLA-W7 as a material for radiation shielding.Öğe Improving electrical, optical and radiation shielding properties of polyvinyl alcohol yttrium oxide composites(Elsevier, 2023) Issa, Shams A. M.; Abulyazied, D. E.; Alrowaily, Albandari W.; Saudi, H. A.; Ali, E. S.; Henaish, A. M. A.; Zakaly, Hesham M. H.This research aims to study the impact of yttrium oxide on the radiation protection features of polyvinyl alcohol (PVA) for gamma shielding applications. The yttrium oxide (Y2O3) was instilled through the PVA matrix by different contents (x 1/4 0.1 wt%, 0.3 wt%, 0.7 wt%, 0.9 wt%). The morphology of the prepared PVA/Y2O3 composites was characterized using scanning electron microscopy (SEM). The samples were investigated using absorption edge, transmittance spectra and dielectric properties. The transmittance and the bandgap energy decrease as the Y2O3 content increases while there is an increase in epsilon 0 and epsilon 00 as well as the ac conductivity with the content increment of Y2O3 till 0.7 wt%. The temperature dependence of the dc conductivity was measured for all samples in the range of 260-460 K, and it increases with the temperature increasing. To correlate the electrical characteristics of the PVA/Y2O3 composites with their structure and evaluate electrical properties with the help of equivalent circuit matching with the experimentally electrical response in the impedance spectrum, the radiation protection properties were also investigated to get the radiation shielding performance of these PVA/Y2O3 composite films with varying Y2O3 content. The linear attenuation coefficient (m), half value layer (T0.5), and mass attenuation coefficient (mm) were measured. According to all obtained data, PVA/Y2O3 composite films with various percentages (0.1 wt%, 0.3 wt%, 0.7 wt%, 0.9 wt%) can be used as a radiation shielding material.(c) 2023 Chinese Society of Rare Earths. Published by Elsevier B.V. All rights reserved.Öğe Notable changes in geochemical and mineralogical characteristics of different phases of episyenitization: insights on the radioactive and shielding of the late phase(Frontiers Media Sa, 2023) Taalab, Sherif A.; Zakaly, Hesham M. H.; Ivanov, V.; Alrowaily, Albandari W.; Awad, Hamdy A.; Abed, Neveen S.; Issa, Shams A. M.Kab Amiri granites are submitted to post-magmatic hydrothermal solutions through fracture and faults, causing several alteration processes. The most common processes are episyenitization, saussuritization, hematitization, sericitization, kaolinization, albitization, chloritization, silicification, and muscovitization. Kab Amiri granites are vuggy, with the vugs partially to completely refilled with new constituents. The least episyenitized granites have elevated amounts of Fe, P, Zr, Ni, U, Th, Ba, Y, Hf, Nb, and As, which are correlated with their mobilization from biotite, k-feldspar, plagioclase and metamict zircon. These elemental changes are related the partial albitization, muscovitization, desilicification and chloritizatiom, which lead to the mobilization of these elements and forming of specific mineral association in the least altered granites such as autonite, tripiolite, columbite, Zircon and galena. On the second stage, granites were subjected to intense alteration processes by mineralizing fluids, causing wholly muscovitization of biotite and feldspar, albitization of plagioclase, carbonitization and apatitization. Many elements were mobilized from these altered minerals, including Ti, Al, Mn, Mg, Ca, Na, K, Mo, Cu, Pb, Zn, Ag, Co, Sr, V, Cr, Sn, Rb, Ta, Li, Sc, W, S, In, and Tl, leading to definite mineralization as kaslite, monazite, xenotime, polycrase and apatite. The mineralizing fluids in the least and highly episyenitized granites are incorporated in some ore minerals like uranophane, fergusonite, bazzite and garnet. Notably, the presence of elements such as U, Th, and other heavy metals in Kab Amiri granites highlights the potential for these rocks in radiation shielding applications. The unique combination of elements and minerals resulting from the alteration processes can be leveraged for developing new materials or enhancing existing materials used in radiation shielding.Öğe Radiotoxic 210Po concentration in the Mediterranean Sea sediment and radiation risk assessment of biota(Pergamon-Elsevier Science Ltd, 2023) Abbasi, Akbar; Alrowaily, Albandari W.; Zakaly, Hesham M. H.This research presents the levels and distribution of 210Po in different sediments of the northeastern coast of the Mediterranean Sea. The 210Po activity concentrations were measured using an alpha spectroscopy system. The activity concentrations of 210Po in the sediment samples were in the range between 20.5 +/- 0.7 and 92.8 +/- 1.6 Bq kg-1 dw with an average of 48.2 +/- 1.4 Bq kg-1 dw. The microorganism-enriched sampling sites (bedrock sites) indicated low 210Po concentration than sandy coastal sites. As a result of these measurements, the RESidual RADioactivity (RESRAD) biota code was applied to calculate the tissue concentration rate (CR), internal dose rate, external dose rate, and total dose rate of the exposed tissues. The total dose rates of aquatic animals were found higher than that of riparian animals. The 210Po sediment resource doses to aquatic and riparian animals were found less than the dose level recommended by International Commission on Radiological Protection (ICRP).Öğe The seasonal variation of ambient gamma radiation dose rate and health risk assessment in North Coast, Mediterranean Sea(Springer, 2023) Abbasi, Akbar; Zakaly, Hesham M. H.; Bashiry, Vali; Alrowaily, Albandari W.; Mirekhtiary, FatemehIn this research, the seasonal variations of ambient gamma radiation dose rate and the outdoor gamma radiation risk in the northeast location of Cyprus were investigated by means of an Ion Chamber Survey Meter. The ambient gamma radiation was measured at 100 cm above ground level. The average value of measured ambient gamma dose was 135 nGyh-1, 185 nGyh-1, 187 nGyh-1 and 191 nGyh-1 in winter, autumn, spring, and summer, respectively. The excess lifetime cancer risk (ELCR) values at the tested sites were higher than the worldwide average.Öğe U-238, Th-232 series, and Pu-239+Pu-240 concentration analysis in biological samples of high natural background radiation residents by alpha spectrometry(Springer, 2023) Abbasi, Akbar; Mirekhtiary, Fatemeh; Alrowaily, Albandari W.; Zakaly, Hesham M. H.The purpose of this research was to determine the isotope concentration of the actinide radioelements U-238, Th-232 series, and Pu-239 in biological samples (urine) using the alpha spectroscopy system. The samples were selected from the residence of high natural background radiation (HNBR) area and analyzed using chemical procedure. The separated sample was placed on a membrane filter by the sedimentation method, and it was prepared for counting with the alpha spectrometry system. The average radioactive concentrations found in these samples were as follows: U-234 > Ra-226 > Th-230 > Ra-228 > Th-228 > Ra-224 > Th-232 > Pu-239. The average concentrations of U-234 and Ra-226 were much greater than the other radionuclides.Öğe Unveiling the potentials of polyvinyl alcohol/manganese chloride nanocomposites films: A detailed examination of their structural, spectral, and radiation properties(Elsevier, 2023) Issa, Shams A. M.; Alrowaily, Albandari W.; Oche, Celestine; Henaish, A. M. A.; Halaka, M. M. Abou; Alatawi, Naifa S.; Zakaly, Hesham M. H.Recently, the introduction of inorganic nanoparticles, such as Manganese Chloride (MnCl2), as fillers in these polymers has emerged as an intriguing area of research, potentially enhancing their properties, and expanding their applications further. This study provides a comprehensive investigation into the influence of MnCl2 nanoparticles on PVA, forming PVA/ MnCl2 polymeric nanocomposite films. The research aims to enhance the understanding of the interactions between PVA and MnCl2, and the resultant structural, spectral, and radiation properties of the investigated nanocomposite films. The study incorporated the preparation of films with varying weight percentages of MnCl2 nanoparticles. X-ray diffraction patterns confirmed the presence of MnCl2 within the PVA structure and suggested strong interactions between the constituents. The FTIR spectral analysis was conducted to identify changes in the chemical bonds due to MnCl2 doping, employing spectral deconvolution to gain deeper insights into these changes. The study also considered density measurements using Archimedes' principle, providing insights into the physical properties of the nanocomposites. The radiation interaction properties of the polymeric nanocomposite films were evaluated to explore potential applications in radiation protection. The results shed light on the impact of MnCl2 doping on PVA and suggest the promising potential of these nanocomposites in numerous applications, including optoelectronics and radiation shielding. This study propels the understanding of polymer-nanoparticle interactions forward, offering valuable insights into the design and application of polymeric nanocomposites.Öğe Unveiling the structural, optical, and electromagnetic attenuation characteristics of B2O3-SiO2-CaO-Bi2O3 glasses with varied WO3 content(Pergamon-Elsevier Science Ltd, 2023) Ali, Ahmed S.; Alrowaily, Albandari W.; Issa, Shams A. M.; Rashad, M.; Elsaman, Reda; Zakaly, Hesham M. H.This study provides insight into B2O3-SiO2-CaO-Bi2O3 glasses where novel results for the effects of WO3 content on its structural and optical properties have been demonstrated. Thus, provides useful data for developing new glasses for optical and electromagnetic shielding applications. The effect of WO3 content on the structural and optical properties of B2O3-SiO2-CaO-Bi2O3 glasses was investigated along with radiation shielding features which have been calculated by XCOM program. BSCB/W-00, BSCB/W-2.5, BSCB/W-5.0, BSCB/W-7.5, BSCB/W10, BSCB/W-15, and BSCB/W-20 refer to seven samples of bismuth borosilicate glass system doped with 0.0, 2.5, 5, 7.5, 10, 15, and 20% of WO3, respectively, synthesized using the melt quenching technique. The density of the glasses decreased with increasing WO3 content due to the replacement of Bi2O3 with lower-density WO3. It was found that the absorption coefficient decreased with increasing WO3 content up to 10 wt%, but showed an opposite trend for samples with higher WO3 content. The optical band gap and the transition type were affected as the WO3 content increased. The electromagnetic wave decay or skin depth was also calculated. Overall, the shielding effectiveness of investigated samples BSCB/W-00, BSCB/W-2.5, BSCB/W-5.0, BSCB/W-7.5, BSCB/W10, BSCB/W-15, and BSCB/W-20 has reduced with the enlargement of the WO3 concentration. BSCB/W-00, out of all the samples tested, has the highest shielding efficiency.
