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RISS 인기검색어
- 검색키워드
- 저자 : Mohamed Y. Hanfi (검색결과 4 건)
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Physical characterization and radiation shielding features of B2O3-As2O3 glass ceramic
Mohamed Y. Hanfi,Ahmed K. Sakr,A.M. Ismail,Bahig M. Atia,Mohammed S. Alqahtani,K.A. Mahmoud 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.1
The synthetic B2O3eAs2O3 glass ceramic are prepared to investigate the physical properties and the radiation shielding capabilities with the variation of concentration of the As2O3 with 10, 20, 30, and 40%, respectively. XRD analyses are performed on the fabricated glasseceramic and depicted the improvement of crystallinity by adding As2O3. The radiation shielding properties are studied for the B2O3eAs2O3 glass ceramic. The values of linear attenuation coefficient (LAC) are varied with the variation of incident photon gamma energy (23.1e103 keV). The LAC values enhanced from 12.19 cm1e37.75 cm1 by raising the As2O3 concentration from 10 to 40 mol% at low gamma energy (23.1 keV) for BAs10 and BAs40, respectively. Among the shielding parameters, the halfevalue layer, transmission factor, and radiation protection efficiency are estimated. Furthermore, the fabricated samples of glass ceramic have low manufacturing costs and good shielding features compared to the previous work. It can be concluded the B2O3eAs2O3 glass ceramic is appropriate to apply in X-ray or low-energy gamma-ray shielding applications.
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The radioactivity levels and beta dose rate assessment from dental ceramic materials in Egypt
Hasabelnaby Mohamed,Hanfi Mohamed Y.,El-Gamal Hany,El Gindy Ahmed H.,Khandaker Mayeen Uddin,Salaheldin Ghada 한국원자력학회 2024 Nuclear Engineering and Technology Vol.56 No.9
There is a lack of available data on the radioactivity levels of these materials, despite the potential risks they may pose to patients, dental technicians, and dentists. A total of forty samples were collected from different dental markets in Egypt. Using an NaI(Tl) detector, the gamma-ray spectrometer measured the activity levels of uranium-238, radium-226, thorium-232, and potassium-40. The findings revealed that the mean concentration of 238U (below the minimum detectable activity, MDA), 226Ra (135 ± 5 and 132 ± 5 Bq/kg), 232Th (187 ± 4 and 243 ± 8 Bq/kg), and 40K (1560 ± 52 and 2501 ± 89 Bq/kg) in feldspar and zirconia (ZrO2) dental ceramic samples, respectively, were all within the limits established by the International Organization for Standardization (ISO) and the European Commission (EC). The use of feldspar and zirconia dental ceramics to restore all teeth would result in an estimated maximum beta dose of 1.5 mGy/year to the oral tissue. The results suggest that there is no cause for concern regarding any additional beta dose to the oral cavity from the use of feldspar and zirconia dental ceramics.
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Assessment of radioactivity levels and radiation hazards in building materials in Egypt
Ahmed E. Abdel Gawad,Mohamed Y. Hanfi,Mostafa N. Tawfik,Mohammed S. Alqahtani,Hamed I. Mira Korean Nuclear Society 2024 Nuclear Engineering and Technology Vol.56 No.2
Different degrees of natural radioactivity found in quartz can have negative consequences on health. Quartz vein along the investigated Abu Ramad area, Egypt, had its natural radioactivity assessed. The HPGe spectrometer was used to determine the role played by the radionuclides <sup>238</sup>U, <sup>232</sup>Th, and <sup>40</sup>K in the gamma radiation that was emitted, and the results showed that these concentrations are 484.64 ± 288.4, 36.8 ± 13.1 and 772.2 ± 134.6 Bq kg<sup>-1</sup> were higher than the corresponding reported global limits of 33, 45, and 412 Bq kg<sup>-1</sup> for each radionuclide (<sup>238</sup>U, <sup>232</sup>Th, and <sup>40</sup>K). Among the radiological hazard parameters, the excess lifetime cancer risk (ELCR) is estimated and it's mean value of ELCR (1.2) is higher than the permissible limit of 0.00029. The relationship between the radionuclides and the associated radiological hazard characteristics was investigated based on multivariate statistical methods including Pearson correlation, principal component analysis (PCA), and hierarchical cluster analysis (HCA). According to statistical research, the radioactive risk of quartz is primarily caused by the <sup>238</sup>U, <sup>232</sup>Thand <sup>40</sup>K. Finally, applying quartz to building materials would pose a significant risk to the public.
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Radiological hazards assessment associated with granitoid rocks in Egypt
Abdel Gawad Ahmed E.,Masoud Masoud S.,Khandaker Mayeen Uddin,Hanfi Mohamed Y. 한국원자력학회 2024 Nuclear Engineering and Technology Vol.56 No.6
The present study aimed to assess the radioactive hazards associated with the application of granitoid rocks in building materials. An HPGe spectrometer was used to detect the levels of the radioactive elements uranium-238, thorium-232, and potassium-40 in the granitoid rocks. The results showed that the levels of these elements were lower (38.32 < 33 Bq kg 1), comparable (47.19–45 Bq kg-1) and higher (992.26 ≫> 412 Bq kg 1) than the worldwide limits for 238U, 232Th, and 40K concentration, respectively. The exposure to gamma radiation of granitoid rocks was studied by various radiological hazard variables like the absorbed dose rate (Dair), the outdoor and indoor annual effective dose (AEDout and AEDin), and excess lifetime cancer risk (ELCR). A variety of statistical methods, including Pearson correlation, principal component analysis (PCA), and hierarchical cluster analysis (HCA) was used, to study the relationship between the radioactive elements and the radiological hazards. According to statistical analysis, the main radioactive risk of granitoid rocks is contributed to by the elements uranium-238, thorium-232, and potassium-40. Granitoid rocks can be applied in building materials, but under control to prevent risk to the public.
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