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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 1048-1071页

作者： Huajing Zong Nan Kang Zehao Qin mohamed el Mansori Arts et Metiers Institute of Technology MSMPHESAM UniversitéChâlons-en-Champagne F-51006France Texas A&M Engineering Experiment Station Institute for Manufacturing SystemsCollege Station TX77843USA

The laser powder bed fusion(LPBF) process can integrally form geometrically complex and high-performance metallic parts that have attracted much interest,especially in the molds *** appearance of the LPBF makes it possible to design and produce complex conformal cooling channel systems in ***,LPBF-processed tool steels have attracted more and more *** complex thermal history in the LPBF process makes the microstructural characteristics and properties different from those of conventional manufactured tool *** paper provides an overview of LPBF-processed tool steels by describing the physical phenomena,the microstructural characteristics,and the mechanical/thermal properties,including tensile properties,wear resistance,and thermal *** microstructural characteristics are presented through a multiscale perspective,ranging from densification,meso-structure,microstructure,substructure in grains,to ***,a summary of tool steels and their challenges and outlooks are introduced.

关键词： additive manufacturing laser powder bed fusion tool steel multi-scaled structure mechanical properties thermal properties

Fibrolamellar hepatocellular carcinoma:A rare but unpleasant event

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World Journal of Gastrointestinal Oncology 2022年第6期14卷 1103-1114页

作者： Walaa Abdelhamed mohamed el-Kassas Department of Endemic Medicine Sohag UniversitySohag 14322Egypt Department of Endemic Medicine Faculty of MedicineHelwan UniversityCairo 11795Egypt

Fibrolamellar carcinoma(FLC)is a rare variant of hepatocellular carcinoma(HCC),comprising 1%–9%of all *** is a poorly understood malignancy,which seems to be more prevalent in young patients with no underlying liver *** term“fibrolamellar”is derived from thick fibrous collagen bands surrounding the tumor *** HCC,cirrhosis and viral hepatitis infection are not predisposing to FLC,and it is not associated with elevations in serum *** patients often present with vague abdominal pain,nausea,malaise,and weight *** cases present are at an advanced stage at the time of initial ***,curative treatment options can still be offered to up to 70%of ***(resection/liver transplantation)is the mainstay of treatment and the only potentially curative *** have been less chemoresponsive than the conventional HCC,however,in advanced cases,multimodality treatments can be *** advances in molecular studies of FLC have found a unique DNAJB1–PRKACA fusion transcript in most of the cases *** review aims to describe clinical characteristics,diagnostic methods,and therapeutic modalities for this rare tumor to raise awareness among clinicians and surgeons.

关键词： Fibrolamellar carcinoma Hepatocellular carcinoma Hepatitis Cirrhosis Viral hepatitis infection

Pan-African high-grade metamorphism of southern Sinai, Egypt, fluid inclusion evidence

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Chinese Journal Of Geochemistry 2009年第4期28卷 358-363页

作者： mohamed el Tokhi Abdalla Musallum Geology Department College of Science United Arab Emirates UniversityUnited Arab Emirates

Fluid inclusions in the leucosomes of Wadi Feiran migmatites showed that CO2, H2O and (H2O-CO2) fluids were likely to have been present when partial melting began in these rocks. Low salinity, aqueous fluid, to a lesser extent, CO2-rich fluids are the most abundant fluids. The present study suggests that high-density CO2 inclusions were formed at the earliest stage, while H2O inclusions were formed at the late stage. In an intermediate stage, low-density CO2 and H2O, CO2 inclusions were formed. At the early stage of uplift and during melt crystallization, the CO2-bearing vapour was trapped at grain boundaries. At the late stage of uplift, H2O released at the time of crystallization of the melt was trapped as inclusions.

关键词：流体包裹体西奈半岛变质作用埃及证据二氧化碳局部熔融熔体包裹体

Metabolic aspects of hepatitis C virus

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World Journal of Gastroenterology 2022年第22期28卷 2429-2436页

作者： mohamed el-Kassas Abeer Awad Department of Endemic Medicine Faculty of MedicineHelwan UniversityCairo 11795Egypt Department of Internal Medicine Faculty of MedicineCairo UniversityCairo 11566Egypt

Many metabolic factors are associated with chronic hepatitis C virus(HCV)infection and can influence the course of the illness and impact the progression of liver and non-liver-related diseases through complex *** of these factors impact the course of chronic HCV(CHC)and result in the conceptual translation of CHC from a localized to systemic *** the traditional liver manifestations associated with CHC infection,such as cirrhosis and hepatocellular carcinoma,various extrahepatic disorders are associated with HCV infection,including atherosclerosis,glucose and lipid metabolic disturbances,alterations in the iron metabolic pathways,and lymphoproliferative *** coexistence of metabolic disorders and CHC is known to influence the chronicity and virulence of HCV and accelerates the progression to liver fibrosis and hepatocellular *** resistance is one of the key factors that have a tremendous metabolic impact on ***,there is a great need to properly evaluate patients with CHC infection and correct the modifiable metabolic risk ***,patients with HCV who achieved a sustained virological response showed an overall improvement in glucose metabolism,but the exact evidence still requires further studies with long-term *** review delineates the most recent evidence on the main metabolic factors associated with CHC and the possible influence of chronic HCV infection on metabolic features.

关键词： Hepatitis C virus Metabolic factors Steatosis Insulin resistance

Microstructure and mechanical properties of hot extruded 6016 aluminum alloy/graphite composites

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Journal of Materials Science & Technology 2018年第9期34卷 1580-1591页

作者： mohamed M.el-Sayed Seleman mohamed M.Z.Ahmed Sabbah Ataya Department of Metallurgical and Materials Engineering Faculty of Petroleum and Mining Engineering Suez University 43518 Suez Egypt Suez and Sinai Metallurgical and Materials Research Center of Scientific Excellence (SSMMR-CSE) 43518 Suez Egypt The British University in Egypt Mechanical Engineering Deportment El-Sherouk City 11837 Cairo Egypt Department of Mechanical Engineering College of Engineering AI Imam Mohammad Ibn Saud Islamic University Riyadh 11432 saudi Arabia

The incorporation of graphite particles into AA6016 aluminum alloy matrix to fabricate metal/ceramic composites is still a great challenge and various parameters should be considered. In this study, dense AA6016 aluminum alloy/（0-20 wt%） graphite composites have successfully been fabricated by powder metallurgy process. At first, the mixed aluminum and graphite powders were cold compacted at 200 MPa and then sintered at 500 ℃ for 1 h followed by hot extrusion at 450 ℃. The influence of ceramic phases（free graphite and in-situ formed carbides） on microstructure, physical and mechanical properties of the produced composites were finally investigated. The results show that the fabricated composites have a relative density of over 98%. SEM observations indicate that the graphite has a good dispersion in the alloy matrix even at high graphite content. Hardness of all the produced composites was higher than that of aluminum alloy matrix. No cracks were observed at strain less than 23% for all hot extruded *** strength, reduction in height, ultimate tensile stress, fracture stress, yield stress, and fracture strain of all Al/graphite composites were determined by high precision second order equations. Both compressive and ultimate tensile strengths have been correlated to microstructure constituents with focusing on the in-situ formed ceramic phases, silicon carbide（SiC） and aluminum carbide（Al4 C3）. The ductile fracture mode of the produced composites became less dominant with increasing free graphite content and in-situ formed carbides. Wear resistance of Al/graphite composites was increased with increasing graphite content. Aluminum/20 wt% graphite composite exhibited superior wear resistance over that of AA6016 aluminum alloy.

关键词： AA6016/graphite composites Hot extrusion In-situ carbides Mechanical properties Wear resistance Fracture behavior

Wireless Sensor Networks Routing Attacks Prevention with Blockchain and Deep Neural Network

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Computers, Materials & Continua 2022年第3期70卷 6127-6140页

作者： mohamed Ali Ibrahim A.Abd el-Moghith mohamed N.el-Derini Saad M.Darwish Higher Institute for Tourism Hotels and ComputerAl-SeyoufAlexandria21533Egypt Department of Information Technology Institute of Graduate Studies and ResearchAlexandria University21526Egypt Department of Computer and Systems Engineering Faculty of EngineeringAlexandria UniversityAlexandria21544Egypt

Routing is a key function inWireless Sensor Networks(WSNs)since it facilitates data transfer to base *** attacks have the potential to destroy and degrade the functionality ofWSNs.A trustworthy routing system is essential for routing security andWSN *** methods have been implemented to build trust between routing nodes,including the use of cryptographic methods and centralized ***,the majority of routing techniques are unworkable in reality due to the difficulty of properly identifying untrusted routing node *** the moment,there is no effective way to avoid malicious node *** a consequence of these concerns,this paper proposes a trusted routing technique that combines blockchain infrastructure,deep neural networks,and Markov Decision Processes(MDPs)to improve the security and efficiency of WSN *** authenticate the transmission process,the suggested methodology makes use of a Proof of Authority(PoA)mechanism inside the blockchain *** validation group required for proofing is chosen using a deep learning approach that prioritizes each node’s *** are then utilized to determine the suitable next-hop as a forwarding node capable of securely transmitting *** to testing data,our routing system outperforms current routing algorithms in a 50%malicious node routing scenario.

关键词： Wireless sensor networks trusted routing deep neural network blockchain markov decision

Prospects delineation and evaluation using the CDP gathers characterization, onshore Nile Delta, Egypt

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Petroleum Research 2019年第4期4卷 365-375页

作者： mohamed Hussein Ahmed S.Abu el-Ata mohamed G.el-Behiry Petroleum Engineering Department Faculty of EngineeringFuture University in EgyptEgypt Geophysics Department Faculty of ScienceAin Shams UniversityEgypt Geophysics Department Faculty of ScienceCairo UniversityEgypt

In the last decade, the seismic AVO analysis have become prominent in the direct hydrocarbons indicator(DHI), aimed at characterizing the fluid content or the lithology of a possible reservoir and reducing theexploration drilling risk. This research discuss the impact of studying the common depth point (CDP)gathers on Near, Mid and Far-offsets, to verify the credibility of the amplitude response in the prospectevaluation, through analyzing a case study of two exploratory wells;one has already penetrated a gasbearing sandstone as a reservoir and the other one is dry-sand, but drilled in two different prospects,using the amplitude versus offset (AVO) analysis, to understand the reservoir configuration and itsrelation to the different amplitude response. The results show, that the missing of the short-offset data isthe reason of the false anomaly encountered in the dry sand, due to some urban surface obstacles duringacquiring the seismic data in the field especially, the study area is located in el Mansoura city, which it isa highly cultivated flat terrain, with multiple channels and many large orchards on the edge of the river,and sugar cane and rice fields. Several lessons have been learned, which how to differentiate between thegas reservoirs and non-reservoirs, by understanding the relation between the Near and Far-offset traces,to reduce the amplitude anomalies to their right justification, where missing of Near-offset data led to apseudo-amplitude anomaly. The results led to a high success of exploration ratio as the positives vastlyoutweigh the negatives.

关键词： CDP gathers AVO analysis Seismic attributes Qawasim sands Near-offset

Effect of sintering temperature on microstructure and electrical properties of Sr_(1-x)(Na_(0.5)Bi_(0.5))_(x)Bi_(2)Nb_(2)O_(9) solid solutions

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Journal of Advanced Ceramics 2014年第1期3卷 17-30页

作者： Hana NACEUR Adel MEGRICHE mohamed el MAAOUI Laboratory of Applied Mineral Chemistry Department of ChemistryFaculty of SciencesUniversity Tunis ElManarCampus 2092TunisTunisia

In this study,we investigated the effect of sintering temperature on densification,grain size,conductivity and dielectric properties of Sr_(1-x)(Na_(0.5)Bi_(0.5))_(x)Bi_(2)Nb_(2)O_(9) ceramics,prepared by hydrothermal *** were sintered at different *** increased with sintering temperature,reaching up to 96%at 800℃.A grain growth was observed with increasing sintering *** spectroscopy analyses of the sintered samples at various temperatures were *** in dielectric constant and in Curie temperature with sintering was *** conductivity and activation energy were calculated and attributed to the microstructural factors.

关键词： ceramics sintering light scattering dielectric properties

Entropy Generation for Flow and Heat Transfer of Sisko-Fluid Over an Exponentially Stretching Surface

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Computers, Materials & Continua 2020年第1期62卷 37-59页

作者： mohamed Abd el-Aziz A.M.Aly Department of Mathematics Faculty of ScienceKing Khalid UniversityAbha61411Saudi Arabia Department of Mathematics Faculty of ScienceHelwan UniversityHelwan-Cairo11795Egypt Department of Mathematics Faculty of ScienceSouth Valley UniversityQena83523Egypt

In the present study,the effects of the magnetic field on the entropy generation during fluid flow and heat transfer of a Sisko-fluid over an exponentially stretching surface are *** similarity transformations are used to transfer the governing partial differential equations into a set of nonlinear-coupled ordinary differential ***-Kutta-Fehlberg method is used to solve the governing *** effects of magnetic field parameter,local slip parameterλ,generalized Biot numberγ,Sisko fluid material parameter,Eckert number Ec,Prandtl number Pr and Brinkman number Br at two values of power law index on the velocity,temperature,local entropy generation number N_(G) and Bejan number Be are ***,the tabular forms for local skin friction coefficient and local Nusselt number under the effects of the physical parameters are *** current results are helpful in checking the entropy generation for *** is found that,an extra magnetic field parameter makes higher Lorentz force that suppresses the *** shear thinning fluids(nelocity *** entropy generation number is more for larger generalized Biot number,magnetic field parameter and Brinkman *** local skin friction coefficient increases as magnetic field parameter and material parameter are increase and it decreases as local slip parameter *** local Nusselt number decreases as magnetic field parameter,local slip parameter and Eckert number are increase,while it increases as material parameter,generalized Biot number and Prandtl number are increase.

关键词： Boundary layer entropy generation exponentially stretching surface magnetic field sisko-fluid

Paleoecology of Benthic Foraminifera in Coral Reefs Recorded in the Jurassic Tuwaiq Mountain Formation of the Khashm Al-Qaddiyah Area, Central Saudi Arabia

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Journal of Earth Science 2015年第2期26卷 224-235页

作者： mohamed Youssef Abdelbaset S.el-Sorogy Department of Geology and Geophysics College of Science King Saud University Department of Geology Faculty of Science South Valley University Department of Geology Faculty of Science Zagazig University

Thirty three benthic foraminiferal species belong to 23 genera and 16 families have been recorded from the coral reefs of the Callovian Tuwaiq Formation, Khashm AI-Qaddiyah area, Central Saudi Arabia. Three species： Astacolus qaddiyahensis, Nodosaria riyadhensis, Siderolites jurassica are believed to be new. Nearly all identified foraminifera are of Atlantie-Miditeranean affinity. The foraminiferal assemblage recorded in the present work is mixed of open marine, moderately deep marine conditions associations and shallow to deep lagoon. The reefal part of upper Twiaq Formation may have been deposited in shallow water of lower to middle shelf depth （20-50 m） as indicated by abundant corals and benthic foraminifera. The coral fauna and bearing benthic foraminifera indicated moderate water energy.

关键词： coral reef benthic foraminifera Jurassic Tuwaiq Formation Saudi Arabia.