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Petrology, geochemistry, radioactivity, and m–W type rare earth element tetrads of el Sela altered granites, south eastern desert,Egypt

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Acta geochimica 2019年第1期38卷 95-119页

作者： A.m.el mezayen m.A.Heikal m.g.el-feky H.A.Shahin I.K.Abu Zeid S.R.Lasheen geology Department Faculty of Science Al Azhar University Nuclear material Authority

The southern part of the Eastern Desert of Egypt—about 30 km southwest of Abu-Ramad city—is mainly covered by ophiolitic rocks(Sul Hamed), island arc assemblage, younger granites(muscovite granites of Qash Amer and two mica granites of el Sela), and various acidic and basic dikes. Field, petrological, and geochemical studies indicate that the el Sela shear zone has been subject to hydrothermal and supergene alteration such as kaolinization, albitization, sericitization, and hematitization. It is invaded by quartz ENE–WSW veins associated with hydrothermal alteration accompanied by radioactive mineralization. The investigated younger granitic rocks had very low contents of compatible elements, such as Cr, Ni,and Co; and high contents of incompatible elements, such as Zr, and large ion lithophiles, such as Sr, especially in the el Sela shear zone. major oxide and trace element analyses revealed calc-alkaline affinity and peraluminous *** highly differentiated granitic rocks' lower Zr/Hf and higher Y/Ho than the normal ratio are consistent with hydrothermal alteration. most samples had rare earth element(REE)-patterns with an m-type tetrad effect in the first and fourth segments and a W-type tetrad in the third segment. The average ∑REE in the studied granites was lower than the world granite average; the ratio of light to heavy REEs greater. The main radioactive, uranium-bearing, and uraniferous Fe and mn minerals are uranothorite,autunite, uranophane and autunite as compounds, kasolite,columbite, xenotime, uranophane-bearing zircon and jarosite, silver-bearing pyrite, hematite, and autunite-bearing pyrolusite.

关键词： geochemistry REE-tetrad effect Radioactive minerals Radiometric measurements Qash Amer el Sela

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Low-temperature alteration of uranium–thorium bearing minerals and its significance in neoformation of radioactive minerals in stream sediments of Wadi el-Reddah, North Eastern Desert, Egypt

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Acta geochimica 2020年第1期39卷 96-115页

作者： O.A.Ebyan H.A.Khamis A.R.Baghdady m.g.el-feky N.S.Abed geology Department Faculty of ScienceAin Shams UniversityCairo 11566Egypt Nuclear materials Authority(NmA) P.O.Box 530El-MaadiCairoEgypt

The stream sediments of Wadi el Reddah(North Eastern Desert,Egypt)are geochemically and mineralogically *** content of radioactive and other heavy minerals is mainly represented by thorite,uranothorite,zircon,monazite,xenotime,columbite,fergusonite,and unknown rare earth elements(REEs)bearing minerals as well as *** emphasis on REE content of thorite,uranothorite,zircon and xenotime has been done to correlate them with the increase of uranium contents in these *** key evidence for the presence lowtemperature alteration processes includes the presence of some zircon crystals as remnants after complete dissolution of the overgrowth zircon in severe acidic environment,the sulphur content,biogenic minerals,occurrence of unusual minerals as cassiterite pore filling in zircon,variation in the REEs content from the surrounding granites to the stream sediments and the abundance of monazite in the surrounding *** minerals are partially and/or completely altered,which indicated by the pseudomorphism of zircon by xenotime,thorite,and uranothorite.

关键词： Zircon Thorite Xenotime Radioactive minerals Low-temperature alteration Wadi el-Reddah

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geochemistry, mineralogy, and radioactivity of the Abu Furad Area, Central Eastern Desert, Egypt

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Acta geochimica 2019年第2期38卷 307-326页

作者： A.m.el mezayen E.K.Abu Zeid W.S.Hosny m.g.el-feky S.m.Omar S.A.Taalab geology Department Faculty of Science Al Azhar University Nuclear material Authority Cairo Egypt

Abu Furad is in the Central Eastern Desert,Egypt. It comprises metasediments, metavolcanics,metagabbros, syn-to late-orogenic granites, and post-orogenic granites, in addition to numerous dykes and veins of different shapes and composition invading all the older rocks cropping out in the study area. Field, petrographic,mineralogical, and chemical investigations led to the classification of Abu Furad granites as quartz diorite, tonalite,granodiorite, and *** oxide and trace element data revealed that the syn-to late-orogenic granites and post-orogenic granites are peraluminous. Syn-to lateorogenic granites originated from calc-alkaline volcanic arc–related magma; while the post-orogenic granites(syenogranite) are highly fractionated, calc-alkaline granite from a within plate regime. Radiometrically, the studied quartz diorite, tonalite, and granodiorite had lower uranium and thorium contents and higher eU/eTh ratios than the syenogranites. This may indicate that the syn-to late-orogenic rocks originated from sources depleted in these elements. The average e Th/eU ratio of syenogranites was higher than that of average continental crust, suggesting that the syenogranites are relatively depleted in U. The studied altered syenogranites were strongly enriched in U and Th compared to the Earth's crust. On the other hand, the average of e U in pegmatites is lower than the global average for uraniferous pegmatites. The most recorded accessory minerals in the altered syenogranites were thorite, fergusonite, samarskite, columbite, zircon, monazite, xenotime,apatite, fluorite, sphene, atacamite, and malachite, in addition to chromium and nickel inclusions.

关键词： Hydrothermal alterations major oxide and trace elements Radiometry mineralogy geochemistry Altered syenogranites Egypt

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Assembly of functional carboxymethyl cellulose/polyethylene oxide/anatase TiO_(2) nanocomposites and tuning the dielectric relaxation, optical, and photoluminescence performances

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Journal of Semiconductors 2024年第7期45卷 26-38页

作者： Asmaa m.Ismail Abeer A.Reffaee Fawzy g.el Desouky Spectroscopy Department Physics Research InstituteNational Research CentreGizaCairo 12622Egypt microwave Physics and Dielectrics Department National Research CentreDokkiCairoEgypt Solid State Physics Department Physics Research InstituteNational Research CentreGizaCairo 12622Egypt

Nanocomposite films consisting of carboxymethyl cellulose,polyethylene oxide(CmC/PEO),and anatase titanium diox-ide(TO)were produced by the use of sol-gel and solution casting ***2 nanocrystals were effectively incorporated into CmC/PEO polymers,as shown by X-ray diffraction(XRD)and attenuated total reflectance fourier transform infrared(ATR-FTIR)*** roughness growth is at high levels of TO nanocrystals(TO NCs),which means increasing active sites and defects in CmC/*** differential scanning calorimetry(DSC)thermograms,the change in glass transition temperature(Tg)val-ues verifies that the polymer blend interacts with TO *** increment proportions of TO NCs have a notable impact on the dielectric performances of the nanocomposites,as *** electrical properties of the CmC/PEO/TO nanocomposite undergo significant *** nanocomposite films exhibit a red alteration in the absorption edge as the concentration of TO NCs increases in the polymer *** decline in the energy gap is readily apparent as the weight percentage of TO NCs *** photoluminescence(PL)emission spectra indicate that the sites of the luminescence peak maximums show slight variation;peaks get wider,while their intensities decrease dramatically as the concentration of TO *** nanocomposite materials show potential for multifunctional applications including optoelectronics,antireflection coatings,pho-tocatalysis,light emitting diodes,and solid polymer electrolytes.

关键词： anatase TiO_(2) CmC/PEO nanocomposites optical photoluminescent electrical optoelectronics

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Large magnetocaloric effect and magnetic properties of EuRhO3

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Journal of Rare Earths 2024年第9期42卷 1724-1729页

作者： m.Lassri m.Sajieddine A.elouafi A.el Hachmi S.el Ouahbi R.moubah Laboratory of Energy and materials Engineering (LgEm) University of Sultan Moulay SlimaneFaculty of Science and Technology (FST) Institute of Applied Physics (IAP)-School of Industrial management (EmINES) Mohammed Ⅵ Polytechnic University National School of Applied Sciences (ENSA) University of Sultan Moulay Slimane Laboratory of mechanics Production and Industrial Engineering (LMPGI)Higher School of Technology of Casablanca (ESTC)University of Hassan Ⅱ Casablanca Laboratory of Radiation on matter and Instrumentation (LRmI) Faculty of Science and Technology (FST) SettatHassan Ⅰ University Laboatory of Physics of Advanced materials and Thermic (LPmAT) Faculty of Science Ain Chock (FSAC)University of Hassan Ⅱ Casablanca

We report on the structural,magnetic,and magnetocaloric properties of *** oxidation states of Eu and Rh ions were studied using X-ray photoelectron spectroscopy（XPS）.It is found that the Eu ions are mainly in the divalent oxidation state while the Rh ions have+4 ***3powders are found to be antiferromagnetic with a second order magnetic transition at Neel temperature（TN=2.9 K）.Analysis of the magnetic susceptibility versus temperature data in terms of the Curie=Weiss law:(χ=C/（T-θW）) for T>TN,yields θW=-3.1 K and effective magne tic moment ■,which is close to the theoretical value ■.The magnetic entropy change(-ΔSm),was determined by em ploying the thermodynam ic maxwell's *** μ0H=5 T and near TN,■ and relative cooling power（RCP） exhibit large values of 33.7 J/（kg·K） and 238 J/kg,*** large magnitude of-ΔSmand RCP show that the EuRhO3compound could be a potential candidate to be used in cryogenic magnetic refrigeration.

关键词： Cryogenic magnetic refrigeration magnetic properties magnetocaloric effect Rare earths X-ray photoelectron spectroscopy

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Existence results and behavior analysis for nonlinear age-dependent population dynamics problems with conformable fractional operator

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International Journal of Biomathematics 2024年第5期17卷 229-256页

作者： Hiba el Asraoui m'hamed el Omari Ali el mfadel Khalid Hilal Laboratory of Applied mathematics Scientific Computing Sultan moulay Slimane University BP 523 Beni MellalMorocco

In this paper,we investigate the existence of solutions and analyze the large-time behavior for gurtin-maccamy population model involving conformable fractional *** a preliminary step,we construct a generic structure of the solution associated with our proposed model by utilizing some basic properties and tools of conformable fractional *** establish the existence of a unique solution of the given model with the given initial *** last,by using the upper and lower solutions for the characteristic equation,we define the upper and lower boundaries for the obtained solution and describe the large-time behavior of the total population.

关键词： Age-dependent population conformable fractional operator upper and lower boundary of the solution dynamics of populations

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Enhanced heavy and extra heavy oil recovery:Current status and new trends

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Petroleum 2024年第3期10卷 399-410页

作者： Sayed gomaa Khalaf g.Salem A.N.el-hoshoudy mining and Petroleum Engineering Department Faculty of EngineeringAl-Azhar UniversityEgypt Department of Reservoir Engineering South Valley Egyptian Petroleum Holding Company(GANOPE)CairoEgypt PVT Lab-Production Department Egyptian Petroleum Research Institute(EPRI)Cairo 11727Egypt PVT-Service Center Egyptian Petroleum Research Institute(EPRI)Cairo 11727Egypt

Due to the increased demand for energy resources these days,especially due to the Russian-Ukrainian war,the focus of the major countries is turning strongly towards improving oil production,especially heavy and extra heavy oil,which represents 40%of the world oil ***-based and thermal(EOR)procedures are promising techniques for recovering heavy oil reservoirs,but they suffer from a sequence of problems and complications that arise after long-term *** complications comprise steam breakthrough,steam overlap,and steam/rock *** research presents the currently applied techniques to maximize the productivity of heavy oil,such as steam injection,cyclic steam stimulation,in-situ combustion,and steam-assisted gravity *** technologies face numerous obstacles,as they are energy and water-intensive processes that are not environmentally *** research also presents future trends in energy-saving and environmentally friendly techniques that enhance heavy oil recovery through vapor extraction(VAPEX)steam-solvent hybrid techniques,electromagnetic energy,sonication,and *** findings of this review reported that all the presented techniques focus on how to reduce the oil viscosity and in-situ upgrade the crude oil *** turn,these enhance both the productivity rate and oil recovery and minimize the production *** article can be considered a comprehensive review of thermal recovery methods in heavy and extra-heavy oil,in addition to screening criteria used for each method.

关键词： Enhanced oil recovery Heavy crude oil Steam flood Hybrid techniques Nanotechnology

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Classical taxonomy,molecular phylogeny and genetic analysis of the genus Exitianus Ball,1929(Hemiptera:Cicadellidae:Deltocephalinae)from Egypt

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Zoological Systematics 2024年第2期49卷 143-157页

作者： Rabab m.el-Hady Ahmed F.el-Sayed Survey&Taxonomy Department Plant Protection Research InstituteAgriculture Research CentreGizaEgypt microbial genetics Department Biotechnology Research InstituteNational Research CentreGizaEgypt Egypt Center for Research and Regenerative medicine(ECRRm) CairoEgypt

Egyptian species of the leafhopper genus Exitianus Ball,1929,***(St?l,1855),***(Distant,1908),and *** Ross,1968 are ***,morphological descriptions,and a key for their identification are *** this study,we used molecular techniques to confirm morphological identification and detect phylogeny among the three Exitianus *** partial nucleotide sequences of the amplified products obtained were determined by macrogen *** nucleotide sequences of 28S rDNA and COX genes of the EgY-ARC-9,EgY-ARC-4,and EgY-ARC-5 were determined by macrogen Korea,blasted into BLAST at the National Center for Biotechnology Information website(NCBI)and compared with those deposited in the genBank DNA *** results represented the homology percentage between the partial sequences of the 28S rRNA and COX genes from each species and related species obtained from genBank DNA *** morphological identifications of the three Exitianus species were confirmed by molecular characterization and sequencing of 28S rDNA and COX genes and identified as ***,***,and ***,their sequences of 28srDNA and COX genes were deposited in genBank with an accession number(LC670610,LC670607,and OQ196105)for 28srDNA gene and(LC775357,LC775358,and LC775359)for the COX gene.

关键词： Auchenorrhyncha Chaismini taxonomic 28S rDNA phylogenetic

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Advancements,strategies,and prospects of solid oxide electrolysis cells(SOECs):Towards enhanced performance and large-scale sustainable hydrogen production

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Journal of Energy Chemistry 2024年第7期94卷 688-715页

作者： Amina Lahrichi Youness el Issmaeli Shankara S.Kalanur Bruno g.Pollet green Hydrogen Lab(gH2Lab) Hydrogen Research Institute(HRI)Universitédu QuébecàTrois-Rivières(UQTR)3351 boulevard des ForgesTrois-RivièresQuébec G9A 5H7Canada

Solid oxide electrolysis cells(SOECs)represent a crucial stride toward sustainable hydrogen generation,and this review explores their current scientific challenges,significant advancements,and potential for large-scale hydrogen *** SOEC technology,the application of innovative fabrication tech-niques,doping strategies,and advanced materials has enhanced the performance and durability of these systems,although degradation challenges persist,implicating the prime focus for future *** we provide in-depth analysis of the recent developments in SOEC technology,including Oxygen-SOECs,Proton-SOECs,and ***,Hybrid-SOECs,with their mixed ionic conducting electrolytes,demonstrate superior efficiency and the concurrent production of hydrogen and *** with the capacity to harness waste heat,these advancements in SOEC technology present signif-icant promise for pilot-scale applications in *** review also highlights remarkable achieve-ments and potential reductions in capital expenditure for future SOEC systems,while elaborating on the micro and macro aspects of sOECs with an emphasis on ongoing research for optimization and *** concludes with the potential of SOEC technology to meet various industrial energy needs and its significant contribution considering the key research priorities to tackle the global energy demands,ful-fillment,and decarbonization efforts.

关键词： Solid oxide electrolysis cells Proton-SOECs Oxygen-SoECs Hybrid-SOECs Intermediate-high temperature electrolysers Hydrogenproduction

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Urban electric Vehicle Charging Station Placement Optimization with graylag goose Optimization Voting Classifier

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Computers, materials & Continua 2024年第7期80卷 1163-1177页

作者： Amel Ali Alhussan Doaa Sami Khafaga el-Sayed m.el-kenawy marwa m.Eid Abdelhameed Ibrahim Department of Computer Sciences College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of Communications and electronics Delta Higher Institute for Engineering and TechnologyMansoura35511Egypt Faculty of Artificial Intelligence Delta University for Science and TechnologyMansoura35712Egypt Computer Engineering and Control Systems Department Faculty of EngineeringMansoura UniversityMansoura35516Egypt

To reduce the negative effects that conventional modes of transportation have on the environment,researchers are working to increase the use of electric *** demand for environmentally friendly transportation may be hampered by obstacles such as a restricted range and extended rates of *** establishment of urban charging infrastructure that includes both fast and ultra-fast terminals is essential to address this ***,the powering of these terminals presents challenges because of the high energy requirements,whichmay influence the quality of *** the maximum hourly capacity of each station based on its geographic location is necessary to arrive at an accurate estimation of the resources required for charging *** is vital to do an analysis of specific regional traffic patterns,such as road networks,route details,junction density,and economic zones,rather than making arbitrary conclusions about traffic *** vehicle traffic is simulated using this data and other variables,it is possible to detect limits in the design of the current traffic engineering ***,the binary graylag goose optimization(bggO)algorithm is utilized for the purpose of feature ***,the graylag goose optimization(ggO)algorithm is utilized as a voting classifier as a decision algorithm to allocate demand to charging stations while taking into consideration the cost variable of traffic *** on the results of the analysis of variance(ANOVA),a comprehensive summary of the components that contribute to the observed variability in the dataset is *** results of the Wilcoxon Signed Rank Test compare the actual median accuracy values of several different algorithms,such as the voting ggO algorithm,the voting grey wolf optimization algorithm(gWO),the voting whale optimization algorithm(WOA),the voting particle swarm optimization(PSO),the voting firefly algorithm(FA),and the voting genetic algori

关键词： electric vehicle graylag goose optimization metaheuristics optimization machine learning

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