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Effect of iron addition on microstructure, mechanical and magnetic properties of Al-matrix composite produced by powder metallurgy route

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Transactions of Nonferrous Metals Society of China 2015年第1期25卷 46-53页

作者： a.fathy Omyma EL-KADY Moustafa M.M.MOHAMMED Department of Mechanical Design and Production Engineering Faculty of Engineering Zagazig University Powder Metallurgy Division Manufacturing DepartmentCentral Metallurgical Research and Development Institute Department of Production Technology Faculty of Industrial Education Beni-Suef University

The effect of iron addition on the microstructure, mechanical and magnetic properties of Al-matrix composite was studied. Mechanical mixing was used for the preparation of 0, 5%, 10% and 15% Fe-Al composites（mass fraction）. Mixtures of Al-Fe were compacted and sintered in a vacuum furnace at 600 °C for 1 h. X-ray diffraction（XRD） of the samples containing 5% and 10% Fe indicates the presence of Al and Fe peaks, while sample containing 15% Fe reveals Al and Al13Fe4 peaks. The results show that both densification and thermal conductivity of the composites decrease by increasing the iron content. The presence of iron in the composite improves the compressive strength and the hardness. The strengthening mechanism is associated with the grain refinement of the matrix and uniform distribution of the Fe particles, as well as the formation of Al13Fe4 intermetallic. The measured magnetization values are equal to 0.3816×10-3 A·m2/g for 5% Fe sample and increases up to 0.6597×10-3 A·m2/g for 10% Fe sample, then decreases to 0.0702×10-3 A·m2/g for 15% Fe sample. This can be explained by the formation of the diamagnetic Al13Fe4 intermetallic compound in the higher Fe content sample detected by XRD analysis.

关键词： Al-Fe composite powder metallurgy microstructure mechanical properties magnetic properties

儿童Gaucher病神经元病变1H-MRS

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国际医学放射学杂志 2014年第1期 85-86页

作者： A.A.K.A.Razek A.Abdalla N.A.Gaber a.fathy A.Megahed T.Barakat 高丽娟 Department of Diagnostic Radiology Mansoura Faculty of Medicine Mansoura University

目的评价儿童Gaucher病(NGD)1H-MRS的临床价值。方法本项前瞻性研究对21例连续的儿童NGD病例进行研究,其中急性期7例、慢性期14例,包括男13例、女

关键词：神经元病变 Gaucher病儿童中枢神经系统

Gut virome:New key players in the pathogenesis of inflammatory bowel disease

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World Journal of Methodology 2025年第2期15卷 27-43页

作者： Helal F Hetta Rehab Ahmed Yasmin N Ramadan Hayam fathy Mohammed Khorshid Mohamed M Mabrouk Mai Hashem Department of Medical Microbiology and Immunology Faculty of MedicineAssiut UniversityAssiut 71515Egypt Division of Microbiology Immunology and BiotechnologyFaculty of pharmacyUniversity of TabukTabuk 71491Saudi Arabia Division of Microbiology Immunology and BiotechnologyDepartment of Natural Products and Alternative MedicineFaculty of PharmacyUniversity of TabukTabuk 71491Saudi Arabia Department of Internal Medicine Division HepatogastroenterologyAssiut UniversityAssiut 71515Egypt Department of Clinical Research Egyptian Developers of Gastroenterology and Endoscopy FoundationCairo 11936Egypt Department of Internal Medicine Faculty of Medicine.Tanta UniversityTanta 31527Egypt Department of Tropical Medicine Gastroenterology and HepatologyAssiut University HospitalAssiut 71515Egypt

Inflammatory bowel disease(IBD)is a chronic inflammatory illness of the *** the mechanism underlying the pathogenesis of IBD is not fully under-stood,it is believed that a complex combination of host immunological response,environmental exposure,particularly the gut microbiota,and genetic suscept-ibility represents the major *** gut virome is a group of viruses found in great frequency in the gastrointestinal tract of *** gut virome varies greatly among individuals and is influenced by factors including lifestyle,diet,health and disease conditions,geography,and *** majority of research has focused on the significance of gut bacteria in the progression of IBD,although viral populations represent an important component of the *** conducted this review to highlight the viral communities in the gut and their expected roles in the etiopathogenesis of IBD regarding published research to date.

关键词： Inflammatory bowel disease Pathogenesis Gut virome Bacteriophage Eukaryotic viruses

Hydraulic jump basins with wedge-shaped baffles

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第7期13卷 519-525页

作者： Ashraf fathy ELLAYN Institute of Port Coastal and Offshore Engineering Zhejiang University

This laboratory study deals with the hydraulic jump properties for an artificially roughened bed with wedge-shaped baffle blocks. The experiments were conducted for both smooth and rough beds with a Froude number in the range of 3.06≤F1≤10.95 and a relative bed roughness ranging 0.22≤KR≤1.4. The data from this study were compared with those of rectangular baffle blocks. New experimental formulae were developed for determining the sequent depth ratio and the hydraulic jump length in terms of the inflow Froude number and relative bed roughness. Bélanger's jump equation of a rectangular channel was extended to account for the implications of the bed shear stress coefficient attributable to channel bed roughness. It was found that, in comparison with the smooth bed, the wedge-shaped bed roughness reduced the sequent depth of the hydraulic jump by approximately 16.5% to 30% and the hydraulic jump length by approximately 30% to 53%.

关键词： Energy dissipater Hydraulic jump Stilling basins Wedge-shaped bed roughness

Effects of variable properties on MHD heat and mass transfer flow near a stagnation point towards a stretching sheet in a porous medium with thermal radiation

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Chinese Physics B 2012年第5期21卷 353-363页

作者： A.M.Salem Rania.fathy Department of Basic Science Faculty of Computer&InformaticsSuez Canal University Department of Mathematics Faculty of ScienceZagazig University

The effect of variable viscosity and thermal conductivity on steady magnetohydrodynamic（MHD） heat and mass transfer flow of viscous and incompressible fluid near a stagnation point towards a permeable stretching sheet embedded in a porous medium are presented,taking into account thermal radiation and internal heat genberation/*** stretching velocity and the ambient fluid velocity are assumed to vary linearly with the distance from the stagnation *** Rosseland approximation is used to describe the radiative heat flux in the energy *** governing fundamental equations are first transformed into a system of ordinary differential equations using a scaling group of transformations and are solved numerically by using the fourth-order Rung-Kutta method with the shooting technique.A comparison with previously published work has been carried out and the results are found to be in good *** results are analyzed for the effect of different physical parameters,such as the variable viscosity and thermal conductivity,the ratio of free stream velocity to stretching velocity,the magnetic field,the porosity,the radiation and suction/injection on the flow,and the heat and mass transfer *** results indicate that the inclusion of variable viscosity and thermal conductivity into the fluids of light and medium molecular weight is able to change the boundary-layer behavior for all values of the velocity ratio parameter λ except for λ = *** addition,the imposition of fluid suction increases both the rate of heat and mass transfer,whereas fluid injection shows the opposite effect.

关键词： variable viscosity variable thermal conductivity stagnation point

Performance of beacon safety message dissemination in Vehicular Ad hoc NETworks (VANETs)

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第12期8卷 1990-2004页

作者： YOUSEFI Saleh fathy Mahmood BENSLIMANE Abderrahim Computer Engineering Faculty Iran University of Science and TechnologyNarmak Tehran 16846-13114 Tehran Iran Laboratoire d'Informatique d'Avignon LIA 339 chemin des Meinajaries BP 1228-84911 Avignon cedex 9 France

Currently, there is a growing belief that putting an IEEE 802.11-like radio into road vehicles can help the drivers to travel more safely. Message dissemination protocols are primordial for safety vehicular applications. There are two types of safety messages which may be exchanged between vehicles: alarm and beacon. In this paper we investigate the feasibility of deploying safety applications based on beacon message dissemination through extensive simulation study and pay special attention to the safety requirements. Vehicles are supposed to issue these messages periodically to announce to other vehicles their current situation and use received messages for preventing possible unsafe situations. We evaluate the performance of a single-hop dissemination protocol while taking into account the quality of service (QoS) metrics like delivery rate and delay. We realize that reliability is the main concern in beacon message dissemination. Thus, a new metric named effective range is defined which gives us more accurate facility for evaluating QoS in safety applications specifically. Then, in order to improve the performance, the effects of three parameters including vehicle's transmission range, message transmission's interval time and message payload size are studied. Due to special characteristics of the safety applications, we model the relationship between communication-level QoS and application-level QoS and evaluate them for different classes of safety applications. As a conclusion, the current technology of IEEE 802.11 MAC layer has still some challenges for automatic safety applications but it can provide acceptable QoS to driver assistance safety applications.

关键词： Safety applications Inter-vehicle communications Vehicular Ad hoc NETworks (VANETs) Application level QoS Effective range

Hydromagnetic flow of a Cu water nanofluid past a moving wedge with viscous dissipation

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Chinese Physics B 2014年第4期23卷 365-372页

作者： A.M.Salem Galal Ismail Rania.fathy Department of Mathematics Faculty of Science and Arts Qassim University Department of Basic Science Faculty of Computers and Informatics Suez Canal University Department of Mathematics Faculty of Science Zagazig University

A numerical study is performed to investigate the flow and heat transfer at the surface of a permeable wedge immersed in a copper （Cu）-water-based nanofluid in the presence of magnetic field and viscous dissipation using a nanofluid model proposed by Tiwari and Das （Tiwari I K and Das M K 2007 Int. J. HeatMass Transfer 50 2002）. A similarity solution for the transformed governing equation is obtained, and those equations are solved by employing a numerical shooting technique with a fourth-order Runge-Kutta integration scheme. A comparison with previously published work is carried out and shows that they are in good agreement with each other. The effects of velocity ratio parameter ~, solid volume fraction tp, magnetic field M, viscous dissipation Ec, and suction parameter Fw on the fluid flow and heat transfer characteristics are discussed. The unique and dual solutions for self-similar equations of the flow and heat transfer are analyzed numerically. Moreover, the range of the velocity ratio parameter for which the solution exists increases in the presence of magnetic field and suction parameter.

关键词： nanofluid dual solution magnetic field viscous dissipation

Planning VANET infrastructures to improve safety awareness in curved roads

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第12期13卷 918-928页

作者： Hossein GHAFFARIAN Mohsen SORYANI Mahmood fathy School of Computer Engineering Iran University of Science and TechnologyNarmakTehranP.O.Box 13114-16846Iran

We analyze the effect of using a vehicular ad-hoc network(VANET) on accident *** shown in our analysis,a higher frequency of safety packets can prevent accidents,even for high speed vehicles and dense *** overcome connectivity problems in blind crossing situations,a genetic algorithm(GA) based method is presented for VANET infrastructure *** proposed approach tries to remove coverage sight holes in low sight distance cases in a traveling path in the *** such places,drivers might not have enough sight for proper action and also environmental obstacles prevent direct communication between ***,curved roads affect *** results show that the density of vehicles is increased right before a curve and is decreased after ***,in this kind of road,a high frequency of packet generation may not act well in accident *** method proposed in this paper tries to cover such places considering the lowest safety distances according to traffic *** this,the road must be covered directly by ***,the problem is to find the best number and also positions of road side *** GA,the algorithm minimizes the summation of total uncovered and overlapped points in the roads which are covered by more than one *** on a real road map confirmed the capabilities of the proposed approach.

关键词： VANET Infrastructure Traffic theory Minimum safety requirement Genetic algorithm

An Intelligent Harmonic Synthesis Technique for Air-Gap Eccentricity Fault Diagnosis in Induction Motors

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Chinese Journal of Mechanical Engineering 2017年第6期30卷 1296-1304页

作者： De Z.Li Wilson Wang fathy Ismail Department of Mechanical Engineering Lakehead University Department of Mechanical & Mechatronics Engineering University of Waterloo

Induction motors （IMs） are commonly used in various industrial applications. To improve energy con- sumption efficiency, a reliable IM health condition moni- toring system is very useful to detect IM fault at its earliest stage to prevent operation degradation, and malfunction of IMs. An intelligent harmonic synthesis technique is pro- posed in this work to conduct incipient air-gap eccentricity fault detection in IMs. The fault harmonic series are syn- thesized to enhance fault features. Fault related local spectra are processed to derive fault indicators for IM air- gap eccentricity diagnosis. The effectiveness of the pro- posed harmonic synthesis technique is examined experi- mentally by IMs with static air-gap eccentricity and dynamic air-gap eccentricity states under different load conditions. Test results show that the developed harmonic synthesis technique can extract fault features effectively for initial IM air-gap eccentricity fault detection.

关键词： Air-gap eccentricity Current signal Faultdetection Induction motor