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An approach to evaluate the efficiency of γ-ray detectors to determine the radioactivity in environmental samples

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Chinese Physics C 2014年第6期38卷 60-66页

作者： Mohamed.s.Badawi ahmed.M.el-Khatib samah.M.Diab sherif.s.Nafee Ekram.A.el-Mallah Physics Department Faculty of Science Alexandria University 21511 Alexandria Egypt

This work provides an approach to determine the efficiency of T-ray detectors with a good accuracy in order to determine the concentrations of either naturally occurring or artificially prepared radionuclides. This approach is based on the efficiency transfer formula （ET）, the effective solid angles, the self- absorptions of the source matrix, the attenuation by the source container and the detector housing materials on the detector efficiency. The experimental calibration process was done using radioactive （Cylindrical ＆ Marinelli） sources, in different dimensions, that contain aqueous 152Eu radionuclide. The comparison point to a fine agreement between the experimental measured and calculated efficiencies for the （NaI ＆ HPGe） detectors using volumetric radioactive sources.

关键词： y-ray detector efficiency efficiency transfer effective solid angles radioactive source

Barrett’s esophagus in a patient with bulimia nervosa:A case report

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World Journal of Clinical Cases 2022年第17期10卷 5841-5845页

作者： ahmed Gouda Mohamed el-Kassas Department of Gastroenterology NMC Ruwais HospitalAbu Dhabi 14638United Arab Emirates Department of Endemic Medicine Faculty of MedicineHelwan UniversityCairo 11795Egypt

BACKGROUND Barrett’s esophagus is a known complication of long-standing gastroesophageal reflux disease,and it is a potential risk factor of developing esophageal *** sUMMARY Here,we present a case of a 47-year-old male patient referred to the gastroenterology clinic for upper endoscopy because he has a long-standing history of heartburn and vomiting after *** examination,he had characteristic findings of self-induced vomiting as abrasions and callosities on the dorsum of the right hand and dental erosions.A detailed history revealed that he had 17 years of binge eating with self-induced *** upper endoscopy showed gastroesophageal reflux grade D with salmon-red mucosal projections,and the biopsy revealed intestinal mucosal *** This case emphasized the importance of considering upper endoscopy screening for Barrett’s esophagus in patients with eating disorders,especially those with self-induced vomiting,as in bulimia nervosa.

关键词： Barrett’s esophagus Bulimia nervosa Gastroesophageal reflux disease Case report

Permutation-substitution image encryption scheme based on a modified chaotic map in transform domain

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Journal of Central south University 2017年第9期24卷 2049-2057页

作者： Ramadan Noha ahmed Hossameldin H el-khamy said E Abd el-samie Fathi E Faculty of electronic Engineering Menofia University Faculty of Engineering Alexandria University

A new chaotic image encryption scheme based on permutation and substitution in the Fourier domain is *** Fourier Transform(FRFT)is used before the encryption scheme to get a large degree of *** permutation is achieved by Baker map and the substitution by a key-related-to-plain-image algorithm based on the modified Logistic *** of the Logistic map is developed to increase the space of the encryption key,and hence increase the *** key of the encryption algorithm dependents on the plain image,and thus,the cipher image is sensitive to both the initial key and the plain image to resist known-plaintext and chosen plaintext *** key space is large and hence the algorithm can effectively resist brute-force *** proposed scheme is examined using different performance evaluation metrics and the results prove that the proposed scheme is highly secure,and it can effectively resist different attacks.

关键词： Backer map chaotic encryption fractional Fourier transform (FRFT) modified Logistic map

La^3+ doped LiCo0.25Zn0.25Fe2O4 spinel ferrite nanocrystals:Insights on structural,optical and magnetic properties

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Journal of Rare Earths 2021年第1期39卷 75-82,I0003页

作者： M.I.A.Abdel Maksoud ahmed el-Ghandour A.H.Ashour M.M.Atta soraya Abdelhaleem ahmed H.el-Hanbaly Ramy Amer Fahim said M.Kassem M.s.shalaby A.s.Awed Materials science Lab. Radiation Physics DepartmentNational Center for Radiation Research and Technology(NCRRT)Atomic Energy AuthorityCairoEgypt Center Photonics and smart Materials(CPsM) Zewail City of Science and TechnologyOctober Gardens6th of October CityGizaEgypt Polymers Physics Lab. Radiation Physics DepartmentNational Center for Radiation Research and Technology(NCRRT)Atomic Energy AuthorityCairoEgypt Egyptian Nuclear and Radiological Regulatory Authority CairoEgypt Radiation Protection and Dosimetry Department National Center for Radiation Research and Technology(NCRRT)Atomic Energy AuthorityCairoEgypt Magnetic and Thermal Lab Solid State&Accelerators DepartmentNational Center for Radiation Research and TechnologyAtomic Energy AuthorityNasr CityCairoEgypt Higher Institute for Engineering and Technology ManzalaDakahliaEgypt

This paper addresses the manipulation of structural,morphology,optical and magnetic properties of LiCo0.25Zn0.25Fe2 O4 ferrite via incorporation of different proportions of La^3+at the expense of iron ions using a sol-gel *** samples were characterized using the X-ray diffraction technique(XRD),Fourier transform infrared(FT-IR)spectroscopy,the energy dispersive X-ray spectra(EDX),inductively coupled plasma optical emission spectroscopy(ICP-OEs),high resolution scanning electron microscopy(sEM),Brunauer-Emmett-Teller(BET)surface area analysis,ultraviolet-diffuse reflectance spectroscopy(UV-DRs),and vibrating sample magnetometer(VsM)*** Rietveld refinements of the samples indicate that at higher concentrations of La^3+,nanostructures with dual phase,*** spinel and orthorhombic LaFeO3 perovskite with space group(Pbnm)*** studies show that the energy band gap(Eg)of the bare LiCo0.25Zn0.25Fe2 O4 ferrite sample(2.18 eV)reaches up to 2.47 eV at x=0.06 and above this concentration,it drops sharply to 2.00 *** the saturation magnetization and the coercivity of LiCo0.25Zn0.25LaxFe2-xO4 are lower than that of LiCo0.25Zn0.25Fe2 O4 ***,the superparamagnetic nature and low values of saturation magnetization and coercivity of LiCo0.25Zn0.25LaxFe2-xO4 NPs are suitable to be applied in transformers core.

关键词： Li-Co-Zn ferrite superparamagnetic nature Optical properties Magnetic behavior Transformers core Rare earths

Design of multi-antenna relaying for OFDM in impulsive noise environment

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Digital Communications and Networks 2019年第3期5卷 189-195页

作者： ahmed el-Mahdy MennaTullah seraj-eldin Professor in the Faculty of Information Engineering and Technology German University in Cairo Cairo Egypt The Faculty of Information Engineering and Technology German University in Cairo Cairo Egypt

A low-complexity multi-antenna relaying scheme is proposed for Orthogonal Frequency Division Multiplexing (OFDM) in the presence of Class-A Impulsive Noise (IN). One way and two way relaying are considered. The signal is transmitted and received by two terminal nodes, each with a single antenna in two time phases. In the proposed design, the processing at the relay consists of Maximal-Ratio Combining (MRC) or Power-based selection Combining (PsC) for receive combining, Amplify and Forward (AF) for power scaling, and space Time Block Coding (sTBC) for transmit diversity. Channel state Information (CsI), Discrete Fourier Transform (DFT), and Inverse Discrete Fourier Transform (IDFT) are not needed. The selective Mapping (sLM) technique is used at the transmitter to reduce the Peak-to-Average Power Ratio (PAPR) of the OFDM signal. Then, at the receiver, the clipping technique is used to reduce the impulses that result from the impulsive noise. The proposed system reduces the complexity of the conventional system, which uses multi-relay with a single antenna. simulation results show that the Bit Error Rate (BER) of the proposed scheme outperforms that of the conventional scheme due to the diversity inherent in the proposed scheme.

关键词： Orthogonal frequency division multiplexing Impulsive noise Multi-antenna relay Reception combining Transmit diversity Peak-to-average power ratio reduction techniques

Magnetic field induction and magnetic force distribution profiles in plasma focus discharge device

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Plasma science and Technology 2021年第7期23卷 110-120页

作者： A A LAsHIN T M ALLAM H A el-sAYED Kamal M ahmed s A WARD H M sOLIMANand M A ABOUelATTA Plasma and Nuclear Fusion Department Nuclear Research CentreEgyptian Atomic Energy AuthorityInshas 13759Egypt Faculty of Engineering Delta University for Science and TechnologyGamasa 11152Egypt electrical Engineering Department Faculty of Engineering at ShoubraBenha UniversityCairo 11629Egypt

We report a simple-to-perform technique to investigate the distribution of the azimuthal magnetic field induction,Bθ,and the induced magnetic force acting on the plasma current sheath(PCs)in a plasma focus(PF)*** in situ measurement technique can undoubtedly be beneficial when other fast-imaging techniques are not *** are not *** work was conducted in the low-energy Mather-type EAEA-PF1 device operated in *** axial distribution(Bθ)z along the coaxial electrodes system was measured with a four magnetic-probe set technique at different radial distances(r=2.625×10^(−2) to 4.125×10^(−2) m)within the annular space between the coaxial electrodes during the 1st and 2nd half cycles of the discharge current waveform,where inner electrode of coaxial electrode system has a+ve polarity and−ve polarity,***,radial and total magnetic force distribution profiles were estimated from Bθ*** of PCs shape in terms of its inclination(curvature)angle,θ,along the axial rundown phase and the correlation between the magnetic forces per unit volume acting on the PCs,the inclination angleθof the PCs,and the formation of a powerful PF action during the 1st and 2nd half cycles is carried *** of inclination angle,θ,on total magnetic force per unit volume acting on PCs axial motion was studied,separately,during the 1st and 2nd half cycles.

关键词： plasma focus azimuthal magnetic field magnetic force inclination angle plasma current sheath

Radial Hahn Moment Invariants for 2D and 3D Image Recognition

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International Journal of Automation and computing 2018年第3期15卷 277-289页

作者： Mostafa el Mallahi Amal Zouhri Anass.el Affar ahmed Tahiri Hassan Qjidaa sidi Mohamed Ben Abdellah University Faculty of Sciences Dhar el MahrazCED-ST Center of Doctoral Studies in Sciences and Technologies

Recently, orthogonal moments have become efficient tools for two-dimensional and three-dimensional（2D and 3D） image not only in pattern recognition, image vision, but also in image processing and applications engineering. Yet, there is still a major difficulty in 3D rotation invariants. In this paper, we propose new sets of invariants for 2D and 3D rotation, scaling and translation based on orthogonal radial Hahn moments. We also present theoretical mathematics to derive them. Thus, this paper introduces in the first case new 2D radial Hahn moments based on polar representation of an object by one-dimensional orthogonal discrete Hahn polynomials, and a circular function. In the second case, we present new 3D radial Hahn moments using a spherical representation of volumetric image by one-dimensional orthogonal discrete Hahn polynomials and a spherical function. Further 2D and 3D invariants are derived from the proposed 2D and 3D radial Hahn moments respectively, which appear as the third case. In order to test the proposed approach, we have resolved three issues： the image reconstruction, the invariance of rotation, scaling and translation, and the pattern recognition. The result of experiments show that the Hahn moments have done better than the Krawtchouk moments, with and without noise. simultaneously, the mentioned reconstruction converges quickly to the original image using 2D and 3D radial Hahn moments, and the test images are clearly recognized from a set of images that are available in COIL-20 database for 2D image, and Princeton shape benchmark（PsB） database for 3D image.

关键词： Orthogonal moments two-dimensional and three-dimensional (2D and 3D) radial Hahn moments Hahn polynomials image reconstruction 2D and 3D rotation invariants.

Nano-crystallites Imine-based Copper(II) Complexes as Mimetics for Copper Oxidase Proteins: synthesis,Characterization,DFT and Oxidase Mimicking Activity

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Chemical Research in Chinese Universities 2024年第6期40卷 1068-1081页

作者： ALHADHRAMI Abdulrahman RAMADAN Abd el-Motaleb FATHY ahmed Department of Chemistry College of ScienceTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Chemistry Department Faculty of ScienceKafr El-Sheikh UniversityKafr El-SheikhEgypt Chemistry Department Faculty of ScienceZagazig UniversityZagazigEgypt

Three tridentate imine ligands containing N2s donors were synthesized via schiff condensation between derivatives of both amino triazine and 2-carbonyl *** reaction of these ligands with CuCl2 in a molar ratio of 1:1 provides three Cu(II) complexes with the general formula [CuLn·Cl_(2)].Analytical,electrical,magnetic,and spectroscopic studies were used to assign the molecular formulae of these metallic *** function theory (DFT) calculations confirmed the structural analysis results obtained from spectroscopic *** various characterization techniques used demonstrated the penta-coordinated slightly distorted square pyramidal structure for the present Cu(II) complexes 1,2,and *** of cyclic voltammetry were done in methanol to define the electrochemical behavior of the current Cu(II) *** biomimetics of catechol oxidase (C.O.);phenoxazinone synthase (PHs) have been studied in the aerobic oxidation of some phenolic substrates,such as 3,5-di-tert-butylcatechol (3,5-DTBCH2);ortho-aminophenol (o-APH3).The three candidate oxidase mimetics showed promising activity in the order 3 > 1 > *** catalytic activity related to the structural properties of existing oxidase mimetics was *** driving force (-ΔG°) controlling the redox reactions of the present biomolecules was calculated from the redox data of Cu(II) complexes 1,2,and *** potential catalytic reaction pathway for the oxidation of the studied phenolic substrates was discussed.

关键词： Nano-crystallite Imine-based copper(II)complex Mimetics of copper oxidase protein synthesis and characterization Density function theory(DFT)calculation

GIs-based flash flooding susceptibility analysis and water management in arid mountain ranges:safaga Region,Red sea Mountains,Egypt

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Journal of Mountain science 2023年第12期20卷 3665-3686页

作者： ahmed E.el-RAYEs Mohamed O.ARNOUs ahmed M.HelMY Geology Department Faculty of ScienceSuez Canal UniversityIsmailia 41522Egypt Geology Department Faculty of ScienceArish UniversityArish 45511 North SinaiEgypt

The safaga Region(sR)is part of the Red sea mountain range in *** flash flooding is now an inescapable event,wreaking havoc and causing massive loss of life and *** majority of the floodwater,however,has been wasted as runoff to the Red sea,which,if used wisely,could meet a fraction of the water demands for a variety of applications in this *** current work aims to use GIs techniques to integrate remote sensing data for evaluating,mitigating,and managing flash floods in *** data set comprised Tropical Rainfall Measuring Mission(TRMM)thematic rainfall data,1:50,000 scale topographical map sheets,geological maps,the AsTER Digital elevation Model(AsTER GDEM),Landsat 7 Enhanced Thematic Mapper"(ETM7+),and Landsat 8 Operational Land *** flash flood risk model of sR is developed using ArcGIs-10.3 geoprocessing tools integrating all the causal factors thematic *** final flood risk model for the sR suggests that 57%of the total basins in the sR are at high risk of *** 38%of all basins are at moderate flood *** remaining 5%of basins are less prone to ***-prone zones were identified,suitable dam-building sites were located,and extremely probable areas for water recharge were *** the basis of reliable scientific data,structural and non-structural mitigation strategies that might reduce the damage susceptibility,alleviate the sensitivity of the flash flood,and best utilize its water supply were recommended.

关键词： Flash floods GIs susceptibility Water management Arid mountains Egypt