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Chinese Journal of Chemical Engineering 2020年第6期28卷 1582-1590页

作者： Ismail M.Ahmed Mostafa M.Hamed sayed s.metwally Chemistry Department College of ScienceJouf UniversitySkakaSaudi Arabia Hot Laboratories and Waste Management Center Atomic Energy Authority13759 CairoEgypt

Modification of perlite using nano-magnetic iron oxide was implemented to produce nano-magneticFe3O4-coated perlite composite(Fe3O4/Perlite).The prepared composite was characterized using scanning Electron Microscopy,Fourier-Transform Infrared spectroscopy and Powder X-ray *** potentiality of both perlite and Fe3O4/Perlite composite to eliminate Cr(VI)from the environmentally relevant water was *** influence of main factors which could affect the adsorption was studied including;pH of medium,shaking time and Cr(VI)ions *** experimental outcome demonstrated that the modification of perlite by nano-magnetic Fe3O4 showed a significantly enhanced Cr(VI)removal efficiency relative to that of unmodified *** the kinetic studies,the experimental data fitted well with the pseudo-second-order ***,it proposes that Langmuir isotherm is more adequate than the Freundlich isotherm for both perlite and modified *** results recommended that Fe3O4/Perlite composite had a great potential as an economic and efficient adsorbent of Cr(VI)from contaminated water,which has huge application potential.

关键词： Nano-magnetic Composite Kinetics Isotherm Perlite Adsorption

Flux measurements for a DD neutron generator using neutron activation analysis

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Nuclear science and Techniques 2018年第4期29卷 66-71页

作者： Walid A. metwally samar El-sayed Ahmad Ababneh David L. Williams Allan X. Chen Department of Nuclear Engineering University of SharjahSharjah 27272 UAE Adelphi Technology 2003 E Bayshore Rd. Redwood CityCA 94063 USA

The fast and maximum thermal neutron fluxes from the DD-109 neutron generator at the University of sharjah were experimentally measured by the activation technique using different neutron reactions. The thermal and fast neutron fluxes were found to be 2.960 × 10~6 and6.186 × 10~7 n/cm^2 s, respectively. This was done to verify the modeling results for the optimum moderator thickness needed to maximize the thermal neutron flux. The optimum moderator thickness was found to be between 3.5 and4 cm. The present data were compared with the detailed MCNP model-based calculation performed in earlier work to simulate the generator.

关键词： Neutron activation analysis Neutron generator Neutron moderation Thermal neutron flux measurement

secret Key Optimization for secure speech Communications

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Computers, Materials & Continua 2022年第8期72卷 3025-3037页

作者： Osama s.Faragallah Mahmoud Farouk Hala s.El-sayed Department of Information Technology College of Computers and Information TechnologyTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Department of Computer science and Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf 32952Egypt Department of Electrical Engineering Faculty of EngineeringMenoufia UniversityShebin El-Kom 32511Egypt

This paper answers three essential questions for audio speech cryptosystems in time and discrete transform *** first question is,what are the best values of sub-keys that must be used to get the best quality and security for the audio cryptosystem in time and discrete transform *** second question is the relation between the number of sub-keys,the number of secret keys used,and the audio speech signal block’s ***,how many possible secret keys can be used to get the best quality and security results for the audio speech cryptosystem in time and discrete transform *** audio cryptosystem discussed before in recent research is applied to answer the three previous *** simulation results and analysis answer all three questions;first,there is no specific,well-defined format or rule for sub-key values that must be used to get a better *** the second question,yes,there is a direct relationship between the number of applicable keys,number of available sub-keys,and block size of speech audio signal and formulated into a first-order *** the third question,each discrete transform domain has a specific acceptable range of sub-keys that imply a particular number of keys that can be used to get a better cryptosystem.

关键词： Audio cryptosystem chaotic baker map secret key size

Yttria Tetragonal Zirconia Biomaterials:Kinetic Investigation

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Journal of Materials science & Technology 2011年第4期27卷 332-337页

作者： Ezzat s.Elshazly s.M.El-Hout M.El-sayed Ali Department of Mechanical Engineering Virginia Commonwealth University Deptartment of Metallurgy Nuclear Research CenterAtomic Energy Authority

The low temperature aging behavior of polycrystalline tetragonal zirconia was investigated to explore the effects on phase transformation occurring during the process. XRD analysis was conducted for the phase identification and the tetragonal to monoclinic phase transformation was determined. The aging of tetragonal zirconia polycrystals doped with 3 mol% Y203 triggers tetragonal to monoclinic phase transformation on the surface of the specimen only, while the penetration inside the bulk of the specimen is very limited. A slight decrease in the mechanical properties was also observed after aging for 40 h. The transformation kinetics show a nucleation and growth mechanism on the specimen surface to be dominant in the low temperature aging in water environment.

关键词： Low temperature degradation 3Y-TZP Kinetics

Use of breakthrough experiment to evaluate the performance of hydrogen isotope separation for metal-organic frameworks M-MOF-74(M=Co, Ni, Mg, Zn)

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science China Chemistry 2020年第7期63卷 881-889页

作者： Yanan si Wenjing Wang El-sayed M.El-sayed Daqiang Yuan state Key Laboratoty of structural Chemistry Fujian Institute o f Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of the Chinese Academy of sciences Beijing 100049China Chemical Refining Laboratory Refining DepartmentEgyptian Petroleum Research InstituteNasr CityCairoEgypt

The unique adsorption performance of metal-organic frameworks(MOFs) indicates a new direction for gas separation and purification. The low-temperature distillation, as a traditional technique for hydrogen isotope separation, is limited as it is a high energy-and cost-intensive process. Instead of utilizing such a conventional separation route, we use ordered microporous frameworks based on a physical adsorption mechanism to solve the challenge of hydrogen isotope separation. Herein we analyze M-MOF-74(M=Co, Ni, Mg, Zn), featuring a hexagonal channel about 11 ? and high density of open metal sites, for their ability to separate and purify deuterium from the hydrogen isotope mixture by dynamic column breakthrough experiments. Our results show that the combination of the strength of binding sites, density of coordinatively unsaturated metal sites and hydrogen isotope adsorption capacity of materials renders Co-MOF-74 as an optimal adsorbent for the capture of deuterium from hydrogen isotope mixtures in a simulated industrial process.

关键词： hydrogen isotope separation breakthrough experiment MOF-74

Variant Wasserstein Generative Adversarial Network Applied on Low Dose CT Image Denoising

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Computers, Materials & Continua 2023年第5期75卷 4535-4552页

作者： Anoud A.Mahmoud Hanaa A.sayed sara s.Mohamed Department of Mathematics and Computer science Faculty of ScienceNew Valley UniversityNew Valley72511Egypt Department of Computer science College of Computer Science and Engineering Taibah UniversityMedina42221KSA Department of Mathematics Faculty of ScienceAssiut UniversityAssiut71516Egypt

Computed Tomography(CT)images have been extensively employed in disease diagnosis and treatment,causing a huge concern over the dose of radiation to which patients are *** the radiation dose to get a better image may lead to the development of genetic disorders and cancer in the patients;on the other hand,decreasing it by using a Low-Dose CT(LDCT)image may cause more noise and increased artifacts,which can compromise the ***,image reconstruction from LDCT image data is necessary to improve radiologists’judgment and *** study proposed three novel models for denoising LDCT images based on Wasserstein Generative Adversarial Network(WGAN).They were incorporated with different loss functions,including Visual Geometry Group(VGG),structural similarity Loss(ssIM),and structurally sensitive Loss(ssL),to reduce noise and preserve important information on LDCT images and investigate the effect of different types of loss ***,experiments have been conducted on the Graphical Processing Unit(GPU)and Central Processing Unit(CPU)to compare the performance of the proposed *** results demonstrated that images from the proposed WGAN-ssIM,WGAN-VGG-ssIM,and WGAN-VGG-ssL were denoised better than those from state-of-the-art models(WGAN,WGAN-VGG,and sMGAN)and converged to a stable equilibrium compared with WGAN and *** proposed models are effective in reducing noise,suppressing artifacts,and maintaining informative structure and texture details,especially WGAN-VGG-ssL which achieved a high peak-signalto-noise ratio(PNsR)on both GPU(26.1336)and CPU(25.8270).The average accuracy of WGAN-VGG-ssL outperformed that of the state-ofthe-art methods by 1 *** prove that theWGAN-VGG-ssL is more stable than the other models on both GPU and CPU.

关键词： Machine learning deep learning image denoising low dose CT loss function

Electrical Conductivity and sensitive Characteristics of Ag-Added BaTiO_3-CuO Mixed Oxide for CO_2 Gas sensing

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Journal of Materials science & Technology 2011年第1期27卷 35-40页

作者： A.M.El-sayed F.M.Ismail s.M.Yakout Inorganic Chemistry Department National Research CentreTahrir StreetDokki P.C.12622 CairoEgypt

Carbon dioxide gas sensors based on BaTiO3-CuO composite with different concentrations of Ag addition（1,1.5 and 2 wt%） have been prepared by stander ceramic method and sintered at 500 and 700℃ for 5 *** conductivity and gas sensing properties of the prepared samples were *** conductivity measurement was used to characterize the obtained sintered sensor *** was found that electrical conductivity and the sensitivity to CO2 were improved with Ag addition and *** correlation between Ag content at different sintering temperature and sensing characteristics towards CO2 is discussed.

关键词： BaTiO3-CuO composite Ag addition Electrical conductivity CO2 sensitive properties

Alumina Effect on the Phase Transformation of 3Y-TZP Ceramics

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Journal of Materials science & Technology 2008年第6期24卷 873-877页

作者： Ezzat s.Elshazly M.El-sayed Ali s.M.El-Hout Department of Metallurgy Nuclear Research CenterAtomic Energy AuthorityCairoEgypt

The isothermal tetragonal-to-monoclinic phase transformation of 3 mol fraction Y2O3-ZrO2 ceramics contain- ing different amounts of Al2O3 during ageing in water at 130℃ for periods of time up to 40 h was investigated to explore the effect of Al2O3 addition on this transformation. The propagation of the transformation into the specimen interiors was suppressed by the addition of Al2O3. The transformation kinetics showed a nucleation and growth mechanism on the specimen surface to be dominant in the low temperature ageing in water environment.

关键词： Phase transformation 3Y-TZP Al2O3 Kinetics

Utilization of HEVC ChaCha20-Based selective Encryption for secure Telehealth Video Conferencing

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Computers, Materials & Continua 2022年第1期70卷 831-845页

作者： Osama s.Faragallah Ahmed I.sallam Hala s.El-sayed Department of Information Technology College of Computers and Information TechnologyTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of Computer science and Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt Department of Electrical Engineering Faculty of EngineeringMenoufia UniversityShebin El-Kom32511Egypt

Coronavirus(COVID-19)is a contagious disease that causes exceptional effect on healthcare organizationsworldwide with dangerous impact on medical services within the *** of the fast spread of COVID-19,the healthcare facilities could be a big source of disease ***,healthcare video consultations should be used to decrease face-to-face communication between clinician and *** video consultations may be beneficial for some COVID-19 conditions and reduce the need for faceto-face contact with a potentially positive patient without *** conditions are like top clinicians who provide remote consultations to develop treatment methodology and follow-up remotely,patients who consult about COVID-19,and those who have mild symptoms suggestive of the COVID-19 *** consultations are a supplement to,and not a substitute for,telephone *** may also form part of a broader COVID-19 distance care strategy that contains computerized screening,separation of possibly infectious patients within medical services,and computerized video-intensive observing of their intensive care that helps reduce ***,the spread of the COVID-19 virus helps to expand the use of video healthcare consultations because it helps to exchange experiences and remote medical consultations,save costs and health procedures used to cope with the pandemic of the COVID-19 virus,and monitor the progress of treatment plans,moment by moment from a distance with precision,clarity and *** this perspective,this paper introduces a high-efficiency video coding(HEVC)ChaCha20-based selective encryption(sE)scheme for secure healthcare video *** proposed HEVC ChaCha20-based sE scheme uses the ChaCha20 for encrypting the sign bits of the Discrete Cosine Transform(DCT)and Motion Vector Difference(MVD)in the HEVC entropy *** main achievement of HEVC ChaCha20-based sE scheme is encrypting the most sensitive video bits with keeping low

关键词： Telehealth HEVC cahcha20 video conferencing

Analysis of the seventh-order Caputo fractional KdV equation:applications to the sawada-Kotera-Ito and Lax equations

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Communications in Theoretical Physics 2023年第8期75卷 14-24页

作者： shabir Ahmad sayed saifullah Department of Mathematics University of MalakandChakdaraDir LowerKhyber PakhtunkhwaPakistan

In this study,we investigate the seventh-order nonlinear Caputo time-fractional KdV *** suggested model's solutions,which have a series form,are obtained using the hybrid ZZ-transform under the aforementioned fractional *** proposed approach combines the homotopy perturbation method(HPM)and the *** consider two specific examples with suitable initial conditions and find the series solution to test their *** demonstrate the utility of the presented technique,we explore its applications to the fractional sawada–Kotera–Ito problem and the Lax *** observe the impact of a few fractional orders on the wave solution evolution for the problems under *** provide the efficiency and reliability of the ZZHPM by calculating the absolute error between the series solution and the exact solution of both the sawada–Kotera–Ito and Lax *** convergence and uniqueness of the solution are portrayed via fixed-point theory.

关键词： seventh-order KdV equation soliton homotopy perturbation method