Ahmed Elkhatib

Prof. Dr. Ahmed Elkhatib


Research Focus & Metrics

Academic Career Length

13Years (2014-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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6 July 2021 in Materials
Verified
Journal Article
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Mohammad Ibrahim AbualsayedMohammad Ibrahim Abualsayed
Mohammad Ibrahim Abualsayed
BABadriah Albarzan
Badriah Albarzan
AAAljawhara H. Almuqrin
Aljawhara H. Almuqrin
AEAhmed Elkhatib
Ahmed Elkhatib
Ashok KumarAshok Kumar
Ashok Kumar
Mohamed ElsafiMohamed Elsafi
Mohamed Elsafi
The gamma radiation shielding ability for CaO-K2O-Na2O-P2O5 glasses were experimentally determined between 0.0595 and 1.41 MeV. The experimental MAC results were compared with theoretical results obtained from the XCOM software to test the accuracy of the experimental values. Additionally, the effect of increasing the P2O5 in the glass composition, or reducing the Na2O content, was evaluated at varying energies. For the fabricated glasses, the experimental data strongly agreed with the XCOM results. The effective atomic number (Zeff) of the fabricated glasses was also determined. The Zeff values start out at their maximum (12.41–12.55) at the lowest tested energy, 0.0595 MeV, and decrease to 10.69–10.80 at 0.245 MeV. As energy further increases, the Zeff values remain almost constant between 0.344 and 1.41 MeV. The mean free path (MFP) of the fabricated glasses is investigated and we found that the lowest MFP value occurs at the lowest tested energy, 0.0595 MeV, and lies within the range of 1.382–1.486 cm, while the greatest MFP can be found at the highest tested energy, 1.41 MeV, within the range of 8.121–8.656 cm. At all energies, the KCNP40 sample has the lowest MFP, while the KCNP60 sample has the greatest. The half value layer (HVL) for the KCNP-X glasses is determined. For all the selected energies, the HVL values follow the order of KCNP40 < KCNP45 < KCNP50 < KCNP55 < KCNP60. The HVL of the KCNP50 sample increased from 0.996 to 2.663, 3.392, 4.351, and 5.169 cm for energies of 0.0595, 0.245, 0.444, 0.779, and 1.11 MeV, respectively. The radiation protection efficiency (RPE) results reveal that decreasing the P2O5 content in the glasses improves the radiation shielding ability of the samples. Thus, the KCNP40 sample has the best potential for photon attenuation applications.

3 September 2021 in Materials
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Journal Article
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MAMahmoud Alabsy
Mahmoud Alabsy
JAJamila S. Alzahrani
Jamila S. Alzahrani
Mohammad Ibrahim AbualsayedMohammad Ibrahim Abualsayed
Mohammad Ibrahim Abualsayed
Mahmoud AbbasMahmoud Abbas
Mahmoud Abbas
Daria TishkevichDaria Tishkevich
Daria Tishkevich
Mohamed ElsafiMohamed Elsafi
Mohamed Elsafi
Polymers are often used in medical applications, therefore, some novel polymers and their interactions with photons have been studied. The gamma-ray shielding parameters for Polymethylpentene (PMP), Polybutylene terephthalate (PBT), Polyoxymethylene (POM), Polyvinylidenefluoride (PVDF), and Polychlorotrifluoroethylene (PCTFE) polymers were determined using the Geant4 simulation and discussed in the current work. The mass attenuation coefficients (μ/ρ) were simulated at low and high energies between 0.059 and 1.408 MeV using different radionuclides. The accuracy of the Geant4 simulated results were checked with the XCOM software. The two different methods had good agreement with each other. Exposure buildup factor (EBF) was calculated and discussed in terms of polymers under study and photon energy. Effective atomic number (Zeff) and electron density (Neff) were calculated and analyzed at different energies. Additionally, the half-value layer (HVL) of the polymers was evaluated, and the results of this parameter showed that PCTFE had the highest probability of interaction with gamma photons compared to those of the other tested polymers.

13 January 2024 in Scientific Reports
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Journal Article
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MAMahmoud T. Alabsy
Mahmoud T. Alabsy
MAMahmoud I. Abbas
Mahmoud I. Abbas
AEAlaa Y. El-Khatib
Alaa Y. El-Khatib
AEAhmed Elkhatib
Ahmed Elkhatib
This research aimed to examine the radiation shielding properties of unique polymer composites for medical and non-medical applications. For this purpose, polymer composites, based on poly methyl methacrylate (PMMA) as a matrix, were prepared and reinforced with micro- and nanoparticles of ZrO2 fillers at a loading of 15%, 30%, and 45% by weight. Using the high purity germanium (HPGe) detector, the suggested polymer composites’ shielding characteristics were assessed for various radioactive sources. The experimental values of the mass attenuation coefficients (MAC) of the produced composites agreed closely with those obtained theoretically from the XCOM database. Different shielding parameters were estimated at a broad range of photon energies, including the linear attenuation coefficient (μ), tenth value layer (TVL), half value layer (HVL), mean free path (MFP), effective electron density (Neff), effective atomic number (Zeff), and equivalent atomic number (Zeq), as well as exposure buildup factor (EBF) and energy absorption buildup factor (EABF) to provide more shielding information about the penetration of γ-rays into the chosen composites. The results showed that increasing the content of micro and nano ZrO2 particles in the PMMA matrix increases μ values and decreases HVL, TVL, and MFP values. P-45nZ sample with 45 wt% of ZrO2 nanoparticles had the highest μ values, which varied between 2.6546 and 0.0991 cm−1 as γ-ray photon energy increased from 0.0595 to 1.408 MeV, respectively. Furthermore, the highest relative increase rate in μ values between nano and micro composites was 17.84%, achieved for the P-45nZ sample at 59.53 keV. These findings demonstrated that ZrO2 nanoparticles shield radiation more effectively than micro ZrO2 even at the same photon energy and filler wt%. Thus, the proposed nano ZrO2/PMMA composites can be used as effective shielding materials to lessen the transmitted radiation dose in radiation facilities.

6 March 2022 in Polymers
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Journal Article
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Mahmoud AbbasMahmoud Abbas
Mahmoud Abbas
AEAhmed Elkhatib
Ahmed Elkhatib
MDMirvat Fawzi Dib
Mirvat Fawzi Dib
HMHoda Ezzelddin Mustafa
Hoda Ezzelddin Mustafa
Mohammad Ibrahim AbualsayedMohammad Ibrahim Abualsayed
Mohammad Ibrahim Abualsayed
Mohamed ElsafiMohamed Elsafi
Mohamed Elsafi
In this study, synthetic silicone rubber (SR) and Bi2O3 micro- and nanoparticles were purchased. The percentages for both sizes of Bi2O3 were 10, 20 and 30 wt% as fillers. The morphological, mechanical and shielding properties were determined for all the prepared samples. The Linear Attenuation Coefficient (LAC) values of the silicon rubber (SR) without Bi2O3 and with 5, 10, 30 and 30% Bi2O3 (in micro and nano sizes) were experimentally measured using different radioactive point sources in the energy range varying from 0.06 to 1.333 MeV. Additionally, we theoretically calculated the LAC for SR with micro-Bi2O3 using XCOM software. A good agreement was noticed between the two methods. The NaI (Tl) scintillation detector and four radioactive point sources (Am-241, Ba-133, Cs-137 and Co-60) were used in the measurements. Other shielding parameters were calculated for the prepared samples, such as the Half Value Layer (HVL), Mean Free Path (MFP) and Radiation Protection Efficiency (RPE), all of which proved that adding nano-Bi2O3 ratios of SR produces higher shielding efficiency than its micro counterpart.

8 November 2022 in Polymers
Verified
Journal Article
Open access
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Mahmoud AbbasMahmoud Abbas
Mahmoud Abbas
AAAbdullah H Alahmadi
Abdullah H Alahmadi
Mohamed ElsafiMohamed Elsafi
Mohamed Elsafi
SASultan A. Alqahtani
Sultan A. Alqahtani
SYsabina yasmin
sabina yasmin
AEAhmed Elkhatib
Ahmed Elkhatib
The use of radiation is mandatory in modern life, but the harms of radiation cannot be avoided. To minimize the effect of radiation, protection is required for the safety of the environment and human life. Hence, inventing a better shield than a conventional shielding material is the priority of researchers. Due to this reason, this current research deals with an innovative shielding material named EKZ samples having a composition of (epoxy resin (90–40) wt %-kaolin clay (10–25) wt %-ZnO-nano particles (0–35) wt %). The numerous compositional variations of (epoxy resin, kaolin clay, and ZnO-nano particles on the prepared EKZ samples varied the density of the samples from 1.24 to 1.95 g/cm3. The radiation shielding parameter of linear attenuation coefficient (LAC), half value layer (HVL), tenth value layer (TVL), and radiation protection efficiency (RPE) were measured to evaluate the radiation diffusion efficiency of newly made EKZ samples. These radiation shielding parameters were measured with the help of the HPGe detector utilizing the three-point sources (Am-241, Cs-137, and Co-60). The obtained results exposed that the value of linear attenuation coefficient (LAC) and radiation protection efficiency (RPE) was maximum, yet the value of half value layer (HVL), and tenth value layer (TVL), were minimum due to the greater amount of kaolin clay and ZnO-nanoparticles, whereas the amount of epoxy resin was lesser. In addition, it has been clear that as-prepared EKZ samples are suitable for low-dose shielding applications as well as EKZ-35 showed a better shielding ability.

31 May 2022 in Polymers
Verified
Journal Article
Open access
PDF file
AEAhmed Elkhatib
Ahmed Elkhatib
TSThanaa I. Shalaby
Thanaa I. Shalaby
AMAli Antar Mohamed
Ali Antar Mohamed
Mohamed ElsafiMohamed Elsafi
Mohamed Elsafi
This work aimed to intensively study polypropylene samples (PP) embedded with micro- and nanoparticles of Bi2O3 for their application in radiation shielding. Samples were prepared by adding 10%, 20%, 30%, 40%, and 50% of Bi2O3 microparticles (mBi2O3) by weight, and adding 10% and 50% of Bi2O3 nanoparticles (nBi2O3), in addition to the control sample (pure polypropylene). The morphology of the prepared samples was tested, and also, the shielding efficiency of gamma rays was tested for different sources with different energies. The experimental LAC were determined using a NaI scintillation detector, the experimental results were compared with NIST-XCOM results, and a good agreement was noticed. The LAC values have been used to calculate some specific parameters, such as half value layer (HVL), mean free path (MFP), tenth value layer (TVL), and radiation protection efficiency (RPE), which are useful for discussing the shielding capabilities of gamma rays. The results of the shielding parameters show that the PP embedded with nBi2O3 gives better attenuation than its counterpart, PP embedded with mBi2O3, at all studied energies.