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Petrology and Geochemistry of Some Ophiolitic Metaperidotites from the Eastern Desert of Egypt:Insights into Geodynamic Evolution and Metasomatic Processes

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Acta Geologica Sinica(English Edition) 2021年第4期95卷 1139-1157页

作者： Abdel-Aal M.ABDel-KARIM Mokhles K.AZER shaimaa a.el-shafei Geology Department Faculty of ScienceZagazig UniversityZagazig 44519Egypt Geological Sciences Department National Research Centre12622-DokkiCairoEgypt

Ophiolitic peridotites exposed in the Eastern Desert(ED)of Egypt record multiple stages of evolution,including different degrees of partial melting and melt extraction,serpentinization,carbonatization and *** present study deals with metaperidotites at two selected localities in the central and southern ED,na.ely Wadi el-Nabáand Wadi Ghadir,*** represent residual mantle sections of a Neoproterozoic dismembered ophiolite that tectonically emplaced over a volcano-sedimentary succession that represents island–arc *** studied metaperidotites are serpentinized,with the development of talc-carbonate and quartz-carbonate rocks,especially along shear and fault *** relics of primary minerals(olivine,orthopyroxene and Cr-spinel)are preserved in a few samples of partiallyserpentinized *** of the Cr-spinel crystals have fresh cores followed by outer zones of ferritchromite and Crmagnetite,which indicates that melt extraction from the mantle protolith took place under oxidizing *** protoliths of the studied metaperidotites were dominated by harzburgites,which is supported by the abundance of mesh and bastite textures in addition to some evidence from mineral and whole-rock chemical *** high Cr#(0.62–0.69;Av.0.66)and low TiO_(2)(els,the higher Fo(89–92;Av.91)and NiO(0.24–0.54 wt%,Av.0.40)contents of the primary olivine relics,together with the high Mg#(0.91–0.93;Av.91)and low CaO,Al2 O3 and TiO_(2)of the orthopyroxene relics,are all comparable with depleted to highly depleted forearc harzburgite from a suprasubduction zone *** investigated peridotites have suffered subsequent phases of metasomatism,from oceanfloor hydrothermal alteration(serpentinization)to magmatic hydrothermal *** enrichment of the studied samples in light rare earth elements(LREEs)relative to the heavy ones(HREEs)is attributed to most probably be due to the contamination

关键词： ophiolitic metaperidotites partial melting melt extraction geodynamic evolution Eastern Desert Egypt

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New carbazole based dyes as effective co-sensitizers for DSSCs sensitized with ruthenium(Ⅱ) complex(NCSU-10)

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Journal of Energy Chemistry 2018年第2期27卷 351-360页

作者： Praveen Naik Rui Su Mohamed R.elmorsy Ahmed el-shafei Airody Vasudeva Adhikari Organic Materials Laboratory Department of ChemistryNational Institute of Technology Karnataka Polymer and Color Chemistry Program North Carolina State University

Herein, we report the design and synthesis of three new D-A type metal-free carbazole based dyes（S1-3）as effective co-sensitizers for dye-sensitized solar cell（DSSC） sensitized with Ru（Ⅱ） complex（NCSU-10）.In this new design, the electron rich carbazole unit was attached to three different electron withdrawing/anchoring species, viz. 4-amino benzoic acid, sulfanilic acid and barbituric acid. The dyes were characterized by spectral, photophysical and electrochemical analysis. Their optical and electrochemical parameters along with molecular geometries, optimized from DFT have been employed to apprehend the effect of the structures of these co-sensitizers on the photovoltaic performances. Further, S1-3 dyes were co-sensitized along with a well-known NCSU-10 dye in order to broaden the spectral response of the co-sensitized devices and hence improve the efficiency. The photovoltaic performance studies indicated that, the device fabricated using S1 dye as co-sensitizer with 0.2 mM of NCSU-10 exhibited improved PCE of 9.55% with JSC of 22.85 mA cm-2, VOC of 0.672 V and FF of 62.2%, whereas the DSSC fabricated with dye NCSU-10（0.2 mM） alone displayed PCE of 8.25% with JSC of 20.41 mA cm-2, VOC of 0.667 V and FF of 60.6%. Furthermore, electronic excitations simulated using time-dependent DFT, were in good agreement with the experimentally obtained results of the co-sensitizers, indicating that the exchange-correlation function and basis set utilized for predicting the spectra of the co-sensitizers are quite appropriate for the calculations. In conclusion, the results showed the potential of simple organic co-sensitizers in the development of efficient DSSCs.

关键词： Carbazole dyes DSSC DFF NCSU-10 Co-sensitization and photovoltaic performance

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Tribological Characterization of Hybrid Metal Matrix Composites Processed by Powder Metallurgy

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Acta Metallurgica Sinica(English Letters) 2017年第8期30卷 781-790页

作者： M. Megahed M. A. Attia M. Abdelhameed A. G. el-shafei Department of Mechanical Design and Production Engineering Faculty of EngineeringZagazig UniversityP.O.Box 44519ZagazigEgypt

Aluminum （Al）-based aluminum oxide （Al2O3） and silicon carbide （SIC） particles hybrid metal matrix com- posites were processed by powder metallurgy technique, followed by sintering at 500 ℃ and then hot extrusion. The tribological properties of these composites with different weight fractions of Al2O3 and SiC were investigated; extrusion process significantly reduces the extent of porosity after cold compaction and sintering processes. Hybridization of the two reinforcements improved hardness and wear resistance of the composites. With an increase in SiC content, hardness was increased and consequently the wear resistance was enhanced also. Scanning electron microscopy observations show a better interfacial bond between matrix and reinforcements and a better distribution of the reinforcements.

关键词： Hybrid metal matrix composite Powder metallurgy Abrasive wear Hardness Porosity

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Development of a Medium Voltage, High Power, High Frequency Four-Port Solid State Transformer

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CES Transactions on electrical Machines and Systems 2022年第1期6卷 95-104页

作者： Ahmad el shafei Saban Ozdemir Necmi Altin Garry Jean-Pierre a.el Nasiri IEEE Department of electrical Engineering University of Wisconsin Milwaukee Department of electrical-electronic Engineering Faculty of TechnologyUniversity of Gazi Department of electrical Engineering University of South Carolina

The power and voltage levels of renewable energy resources is growing with the evolution of the power electronics and switching module *** that,the need for the development of a compact and highly efficient solid-state transformer is becoming a critical task in-order to integrate the current AC grid with the new renewable energy *** objective of this paper is to present the design,implementation,and testing of a compact multi-port solid-state transformer for microgrid integration *** proposed system has a four-port transformer and four converters connected to the *** transformer has four windings integrated on a single common ***,it can integrate different renewable energy resources and energy storage *** port has a rated power of 25 kW,and the switching frequency is pushed to 50 k *** ports are chosen to represent a realistic industrial microgrid model consisting of grid,energy storage system,photovoltaic system,and *** grid port is designed to operate at 4.16 k VAC corresponding to 7.2 kV DC bus voltage,while the other three ports operate at 500 ***,the grid,energy storage and photovoltaic ports are active ports with dual active bridge topologies,while the load port is a passive port with full bridge rectifier *** proposed design is first validated with simulation results,and then the proposed transformer is implemented and *** results show that the designed system is suitable for 4.16 k VAC medium voltage grid integration.

关键词： Co-simulation high frequency high power medium voltage microgrid Multi-port solid state transformer

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Sequence stratigraphic evaluation for the Abu Madi Formation,Abu Madi/el Qar'a/Khilala gas fields,onshore Nile Delta,Egypt

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Petroleum Research 2023年第4期8卷 514-523页

作者： Farouk I.Metwalli Amir Ismail M.S.Metwally Ibrahim M.el shafei Geology Department Faculty of ScienceHelwan UniversityCairoEgypt Desert Research Center CairoEgypt Petrobel Oil Company CairoEgypt

The present study aims to integrate a large set of geological and geophysical data into a comprehensive model describing the depositional features of the Abu Madi/el Qar'a/Khilala gas *** model is based on the sequence stratigraphic framework of the Abu Madi Formation defined using cores,well logs,and time-migrated seismic *** trace attribute sections and relative acoustic impedance sections are also used.A possible depositional pattern for the main Level Ill is established,based on the lithological and petrophysical information derived from the seismic data *** Abu Madi For-mation can be regarded as a depositional sequence recording the progressive drowning of the incised *** sequence is bounded at the base by an erosional unconformity,created by a drop in the level of the Late Messinian Sea,and at the top by a drowning unconformity related to the Early Pliocene *** bottom of Level II divides the Abu Madi sequence into two smaller *** both sequences,gas-bearing traps can be found in the Lowstand Systems Tracts,represented by the fluvial Level Ill and fluvial-deltaic Level Il,respectively.

关键词： Abu Madi gas field el Qar'a area Khilala area Sequence stratigraphy analysis Onshore Nile Delta Abu Madi Formation

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Chitosan/Nanocrystalline Cellulose Biocomposites Based on Date Palm (Phoenix Dactylifera L.) Sheath Fibers

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Journal of Renewable Materials 2019年第6期7卷 567-582页

作者： Abeer M.a.el Amira M.el-shafei Atef A.Ibrahim Mona T.Al-Shemy Cellulose and Paper Department National Research Center33El-Bohouth St.(Former El-Tahrir St.)DokkiP.O.12622GizaEgypt Textile Research Division National Research Center33El-Bohouth St.(Former El-Tahrir St.)DokkiP.O.12622GizaEgypt

In this study,nanocrystalline celluloses were used to enhance physical,mechanical and water vapor barrier properties of chitosan films for potential food packaging *** different mineral acids(sulfuric and phosphoric)were used to extract nanocrystalline cellulose from date palm sheath *** influence of cellulose I and cellulose II on the properties of the isolated nanocrystalline celluloses(e.g.,yield,energy and length of intra-and intermolecular hydrogen bonds,and degree of substitution)were studied *** characteristics of chitosan biocomposite film with phosphorylated nanocrystalline cellulose were compared to those with sulfated nanocrystalline *** showed that besides cellulose polymorphism,the ionic ester groups on the surface of nanocrystalline cellulose is one of the factors influencing the physical,chemical,mechanical,and water vapor barrier properties in chitosan/nanocrystalline cellulose biocomposites.

关键词： Biocomposite Cellulose I Cellulose II Nanocrystalline cellulose(NCC) physico-mechanical properties Thermal stability

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Open Surgery for Retrieval of Patent Foramen Ovale Closure Device Embolized into Right Pulmonary Artery

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World Journal of Cardiovascular Surgery 2017年第5期7卷 67-72页

作者： Ahmad Al Khaddour a.elle Dawson Hussein el shafei FRCS Glasg (C-Th) Damascus University Hospital/Locum Fellow NHS Hospitals Newcastle Underlym UK Damascus University Hospital Damascus Syria

Percutaneous Patent Foramen Ovate PFO/Atrial Septal Defect (ASD) closure has become an increasingly simplified procedure over the past decade. The main advantages of a percutaneous approach include avoidance of surgery, short procedure time and hospital stay. Device embolization is seen ra.ely but it can be fatal. We report this complication following a percutaneous PFO closure in a 44-year-old man. The device was embolized into the distal part of the right pulmonary artery. We removed the device surgically and closed the PFO/ASD.

关键词： Patent Foramen Ovate Atrial Septal Defect Septal Closure Device Embolization of the Right Pulmonary Artery Amplatzer Device Cardiopulmonary Bypass

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An Antilock-Braking Systems (ABS) Control: A Technical Review

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Intelligent Control and Automation 2011年第3期2卷 186-195页

作者： Ayman A. Aly el-shafei Zeidan Ahmed Hamed Farhan Salem 不详

Many different control methods for ABS systems have been developed. These methods differ in their theoretical basis and performance under the changes of road conditions. The present review is a part of research project entitled “Intelligent Antilock Brake System Design for Road-Surfaces of Saudi Arabia” In the present paper we review the methods used in the design of ABS systems. We highlight the main difficulties and summarize the more recent developments in their control techniques. Intelligent control systems like fuzzy control can be used in ABS control to emulate the qualitative aspects of human knowledge with several advantages such as robustness, universal approximation theorem and rule-based algorithms.

关键词： ABS Intelligent Control Fuzzy Control

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Wadi Fatima Thin-Skinned Foreland FAT Belt: A Post Amalgamation Marine Basin in the Arabian Shield

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Open Journal of Geology 2012年第4期2卷 271-293页

作者： Zakaria Hamimi Mohamed Matsah Mohamed el-shafei Abdelhamid el-Fakharani Abdulrahman Shujoon Majid Al-Gabali Department of Structural Geology and Remote Sensing Faculty of Earth Sciences King Abdulaziz University Jeddah Saudi Arabia Geology Departments Faculty of Science Suez Canal University Ismailia Egypt Geology Department Faculty of Science Aswan University Aswan Egypt

Wadi Fatima fold-thrust (FAT) belt is a distinctive foreland FAT belt in the Arabian-Nubian Shield (ANS) involving unmetamorphosed to slightly metamorphosed sedimentary sequence of Fatima Group, deposited over a metamorphic/igneous basement, comprising ortho-amphibolites, orthoand para-schists (with chaotic unmappable blocks of marbles, pyroxenites and metagabbros), older granite (773 ± 16 Ma) and younger granite. The basement exhibits structural fabrics, such as attenuated tight isoclinal folds, sheared-out hinges, NE-SW penetrative foliation and subhorizontal stretched and mineral lineations, related to an oldest prominent dextral shearing phase affected the main Wadi Fatima during the Neoproterozoic. In Wadi Fatima FAT belt, the style of deformation encompasses flexural-slip folding forming mesoscopicand map-scales NE to ENE plunging overturned antiforms and synforms, and a thrust duplex system bounded by floor thrust and sole thrust (basal detachment) dipping gently towards the hinterland (SE to SSE direction) and rises stratigraphically upwards towards the foreland. Such style is affiliated to thin-skinned deformation. Several lines of evidence, such as geometry of interacting outcropand map-scale folds and thrusts, patterns of thrust displacement variations and indications for hinge migration during fold growth, strongly suggest that folding and thrusting in Wadi Fatima FAT belt are geometrically and kinematically linked and that thrusting initiated as a consequence of folding (fold-first kinematics). Thrusts frequently show flat-ramp-flat geometry, and every so often give an impression that they are formed during two main sub-stages;an older sub-stage during which bedding sub-parallel thrusts were formed, and a younger sub-stage which generated younger ramps oblique to bedding. Thrust ramps with SE to SSE dipping regularly show sequential decrease in dip or inclination (due to piggy-back imbrication) into their transport direction which is proposed to be towa

关键词： Fold-Thrust Belt Fatima Group Piggy-Back Imbrication Deformation

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Computing the Pressure Drop of Nanofluid Turbulent Flows in a Pipe Using an Artificial Neural Network Model

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Open Journal of Fluid Dynamics 2012年第4期2卷 130-136页

作者： Mahmoud S. Youssef Ayman A. Aly el-shafei B. Zeidan Department of Mechanical Engineering Faculty of Engineering Taif University Al-Hawiah Saudi Arabia Mechanical Engineering Department Faculty of Engineering Assiut University Assiut Egypt Mechanical Power Engineering Department Faculty of Engineering Mansoura University Mansoura Egypt

In this study, an Artificial Neural Network (ANN) model to predict the pressure drop of turbulent flow of titanium dioxide-water (TiO2-water) is presented. Experimental measurements of TiO2-water under fully developed turbulent flow regime in pipe with different particle volumetric concentrations, nanoparticle diameters, nanofluid temperatures and Reynolds numbers have been used to construct the proposed ANN model. The ANN model was then tested by comparing the predicted results with the measured values at different experimental conditions. The predicted values of pressure drop agreed almost completely with the measured values.

关键词： Artificial Neural Networks (ANNs) Turbulent Flow Nanofluids Pressure Drop

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