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Progress in Natural Science:Materials International 2014年第2期24卷 163-170页

作者： Fahamsyah H.Latief Koji Kakehi el-Sayed M.sherif Department of Mechanical Engineering Tokyo Metropolitan University Center of Excellence for Research in Engineering Materials (CEREM) Advanced Manufacturing Institute King Saud University electrochemistry and Corrosion Laboratory Department of Physical Chemistry National Research Centre (NRC)

An investigation on oxidation behavior of coated Ni-based single crystal superalloy in different surface orientations has been carried out at1100 ℃. It has been found that the {100} surface shows a better oxidation resistance than the {110} one, which is attributed that the {110}surface had a slightly higher oxidation rate when compared to the {100} surface. The experimental results also indicated that the anisotropic oxidation behavior took place even with a very small difference in the oxidation rates that was found between the two surfaces. The differences of the topologically close packed phase amount and its penetration depth between the two surfaces, including the ratio of α-Al2O3 after 500 h oxidation, were responsible for the oxidation anisotropy.

关键词： Ni-based superalloy Oxidation behavior Microstructure Aluminide coating Crystallographic orientation

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

A comparative study of liquid and solid inner contact roxatidine acetate ion-selective electrode membranes

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Chinese Chemical Letters 2015年第6期26卷 714-720页

作者： Mohamed K.Abd el-Rahman Hala E.Zaazaa Samah S.Abbas Badr el-Zeany Zeinab A.el-sherif Dalia A.el-Haddad Analytical Chemistry Department Faculty of PharmacyCairo University National Organization for Drug Control and Research

A comparative study was conducted using two designs of a roxatidine acetate （ROX）-selective electrode; a conventional liquid inner contact called electrode A and a graphite-coated solid contact called electrode 13. The fabrication of electrodes was based on roxatidine-tetraphenylborate （ROX-TPB） as an ion-association complex in a PVC matrix using different plasticizers. electrode A has a linear dynamic range of 2.2 ×10^-5 mol/L to 1.0 ×10^-2 mol/L, with a Nernstian slope of 54.7 mV/decade and a detection limit of 1.4 ×10^-6 mol/L. electrode B shows linearity over the concentration range of 1.0×10^-6 mol/L to 1.0×10^-2 tool/L, with a Nernstian slope of 51.2 mV/decade and a limit of detection of 1.1×10^7 mol/L which is remarkably improved as a result of diminishing ion fluxes in this solid contact, ion-selective electrode. The proposed sensors display useful analytical characteristics for the determination of ROX in bulk powder and its pharmaceutical formulation. The present electrodes show clear discrimination of ROX from several inorganic, organic ions, sugars, some common drug excipients and the degradation product （3-[3-（1-piperidinyl methyl） phenoxy] propyl amine） of ROX. Furthermore, the proposed electrodes were utilized for the determination of ROX in human plasma, where electrode B covers drug Cmax which indicated its applicability to pharmacokinetic, bioavailability and bioequivalent studies. The results obtained by the proposed electrodes were statistically analyzed and compared with those obtained by a reported HPLC method. No significant difference for either accuracy or precision was observed.

关键词： Comparative study Roxatidine acetate Liquid inner contact electrode Solid contact electrode Degradation product Plasma

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

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

Stability analysis for a class of impulsive competitive neural networks with leakage time-varying delays

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Science China(Technological Sciences) 2018年第9期61卷 1384-1403页

作者： AOUITI Chaouki ASSALI el Abed CAO Jin De ALSAEDI ahmed Facuity of Sciences of Bizerta Department of Mathematics Research Units of Mathematics and Applications UR13ES47 University of Carthage Bizerta 7021 Tunisia School of Mathematics Southeast University Nanjing 210096 China School of Mathematics and Statistics Shandong Normal University Jinan 250014 China Nonlinear Analysis and Applied Mathematics (NAAM) Research Group Department of Mathematics King Abdulaziz University Jeddah 21589 Saudi Arabia

In this paper, we consider the existence, the uniqueness, the global exponential stability, the global asymptotic stability, the uniform asymptotic stability and the uniform stability of the equilibrium point of impulsive competitive neural networks with distributed delays and leakage time-varying delays. The existence of a unique equilibrium point is proved by using Brouwer's fixed point theorem. By finding suitable Lyapunov-Krasovskii functional, some sufficient conditions are derived ensuring some kinds of stability. Finally, several examples and their simulations are given to illustrate the effectiveness of the obtained results.

关键词： competitive neural networks leakage delay asymptotic stability global exponential stability impulse

Epidemiology and inflammatory bowel diseases

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World Journal of Gastroenterology 2013年第10期19卷 1505-1507页

作者： ahmed Mahmoud el-Tawil Department of Surgery University Hospital BirminghamEast CorridorGround FloorBirmingham B15 2THUnited Kingdom

The role of alcohol in causing or aggravating the pathogenesis of inflammatory bowel disease is *** finding a conclusive answer for this valuable question we conducted this *** two studies were identified that successfully fulfilled our inclusive *** consumption of alcohol reduced the risk compared with less frequent use(odds ratio = 0.57,95%CI:0.37-0.86).Light alcoholic drinking has protective effects against development of ulcerative *** this inverse association disappeared when smoking was included.

关键词： Epidemiology Inflammatory bowel diseases Crohn’s diseases Ulcerative colitis Alcohol

Handy locoregional flaps for nasal reconstruction

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Chinese Journal of Plastic and Reconstructive Surgery 2023年第1期5卷 13-19页

作者： ahmed Hassan el-Sabbagh Plastic Surgery Center Faculty of MedicineMansoura UniversityElgomhouria StreetMansoura 35516Egypt

Background Skin lesions on the nose are *** surgical techniques have been used for nasal *** options may be autogenous or alloplastic and can be performed in single or multiple *** choice of coverage depends on the nature of the lesion,location on the nose,and available donor *** study aimed to evaluate the surgical outcomes of using locoregional flaps for nasal *** A total of 27 patients underwent *** were 9 men and 18 women,aged 7 months to 93 *** patients presented with involuting hemangioma,five patients with ischemic necrosis of the columella,and five patients with congenital nevus;the remaining 13 patients were previously diagnosed with basal cell *** techniques have been described for nasal reconstruction at our institution from 2016 to *** patients had basal cell carcinoma(n=13).Locoregional flaps and primary sutures were used for nasal *** The complications were *** patient had a superficial infection and one experienced postoperative *** recurrence was observed,and none of the patients asked for a second *** Radical excision of tumors combined with analysis of nasal defects and nearby donor sites is essential for nasal *** use of locoregional flaps leads to consistent and good aesthetic outcomes.

关键词： Nose Skin defect Pedicled flap