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mineralogical, REE-geochemical and fluid inclusion studies on some uranium occurrences, gabal gattar, Northeastern Desert, Egypt

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Chinese Journal Of geochemistry 2011年第4期30卷 430-443页

作者： el-feky m.g. Nuclear materials Authority

Altered granite occurrences (gII and gV) at gabal (g.) gattar are the most important mineralized rocks hosting U-mineralization in Egypt. This mineralized granite is affected by multi-stage hydrothermal alteration proc-esses along brittle structures. This alteration comprises pre-ore alkali-metasomatism and ore-stage hydrothermal hematitization, silicification, kaolinitization, fluoritization, carbonatization and episyenitization. Autoradiographic examination indicates that primary uranium mineralization is present as massive or disseminated ores along tectonic fractures, interstitially in granular minerals, and as cements of breccias. Uraninite, pitchblende and coffinite are the main primary minerals, while uranophane and kasolite are the secondary ones. galena, chalcopyrite, pyrrohtite and pyrite are the most abundant sulphides in association with uranium mineralizations. Hydrothermal alterations at the gII occurrence exhibit an increase in Ni, Cu, Zn, Pb, mo, Nb, Rb beside HREEs and a decrease in Ba, Co, Sr, and V, while alterations at the gV occurrence show enrichment in Ni, Cu, Pb, mo, Nb, Y, HREEs and depletion in Zn, Ba, Co, Rb, Sr, and V. Hydrothermal alteration during the late m.g.atic stage is also identified through the development of unusual REE patterns and fractionation of ratios like Zr/Hf and Y/Ho out of the CHARAC (Charge Radius Con-trolled) range. Non-chondritic Y/Ho ratio at gV is of larger value than chondritic one which may result from wa-ter-rock interaction or print from the encompassing sedimentary rocks. Fluid inclusion studies on quartz and fluorite revealed that temperatures of the mineralizing fluids range between 126 and 240℃ at pressure ≤0.5×108 Pa and give salinity values ranging between 1 wt% and 7.8 wt% NaCl equivalent.

关键词：稀土元素地球化学流体包裹体铀矿化矿物学埃及全球信息基础设施东北部沙漠

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mineralogy,geochemistry,radioactivity and environmental impacts of gabal marwa granites,southeastern Sinai,Egypt

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Chinese Journal Of geochemistry 2011年第2期30卷 175-186页

作者： el feky m.g. el mowafy A.A. Abdel Warith A. Nuclear materials Authority MaadiCairoEgypt

The gabal marwa area is located in the southeastern part of Sinai,*** comprises gneisses and m.g.atites,granodiorites and ***,petrographic,mineralogic and chemical investigations indicated that the gabal marwa granites are classified as granodiorites and *** monzogranites constitute the most predominant rock unit exposed in the study *** have been subjected to hydrothermal alterations,especially along the shear ***,desilicification,nametasomatism and development of spotty or dendritic manganese oxides are the most pronounced alteration *** alterations resulted in the increase of TiO2,Al2O3,FeOt,mnO,CaO,mgO,Na2O,K2O and Cr,Zr,Rb,Y and Sr and the decrease of SiO2,P2O5,Ni,Zn,Ba and *** studies indicated that the altered granites belong to high thorium,high uranium *** U,Th,U and Th,Th/U,Th and U-K variation diagrams suggested that m.g.atic processes controlled the distribution of these elements but the effect of hydrothermal alteration processes were clearly *** Scanning electron microscope and X-ray Diffraction analyses indicated that the most important radioactive minerals include uranothorite,thorite,zircon,monazite and *** and mn minerals were also *** the U,Th,Ra and K activity concentrations obtained for all the studied granitic samples,radium equivalent activity(Raeq),external hazard index(Hex),and internal hazard index(Hin),were calculated to assess the radiation hazard to human beings living in dwellings made of the studied *** monzogranites have radioactivity above the proposed acceptable level and,therefore,caution must be taken when these granites are used as building materials.

关键词： granodiorite monzogranites 放射性 gabal marwa 西奈埃及

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mineralogy,m-type tetrad effect and radioactivity of altered granites at the *** garadi shear zone,central Eastern Desert,Egypt

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Chinese Journal Of geochemistry 2011年第2期30卷 153-164页

作者： el Nahas H.A. el feky m.g. mira H. Nuclear materials Authority P.O. Box 530 Cairo Egypt

The g. Abu garadi area is covered mainly by metasediments, alkali feldspar granites and stream sediments. The alkali feldspar granite is traversed by a major strike-slip fault trending in an N-S direction as well as two subordinate sets of faults trending NW to WNW for the first one and NE for the second one. These faults represent the shear zones affected by m.g.atic (syngenetic) as well as hydrothermal (epigenetic) activities causing alteration of the granitic rocks. The most common alteration features are albitization, greisenization and koalinitization. The mass balance calculations of the studied altered samples show enrichments in Zr, Y, Ni, U, Th and ga and depletions in Zn, Sr, Nb, Ba, Pb, Cu and V. Only the greisenized samples exhibit a significant enrichment in Nb, ∑REE budget and pronounced lanthanide tetrad effect (m-type), especially TE1,4, while weakly expressed tetrad effects are for the other albitized and koalinitized samples. mineralogically, the common accessory minerals in the altered samples include samarskite-(Y), betafite, uranothorite, zircon, fluorite and cassiterite. The greisenized granites contain high eU and eTh than the other altered types, where they are characterized by an assemblage of the radioactive minerals; samarskite-(Y), betafite, uranothorite in addition to zircon. The inter-element relationships between U and Th and also their ratios illustrate that the radioelement distribution in these granites is mainly governed by m.g.atic processes, in addition to post-m.g.atic ones. The distribution of chemical elements and the fractionation of some isovalents within the shear zone are largely controlled by the newly formed mineral phases. With respect to uranium mobilization, uranium m.g.ated from the host alkali feldspar granites of g. Abu garadi, while the shear zones acted as traps for the m.g.ated uranium. moreover, U m.g.ated in the shear zone during greisenization and albitization, and m.g.ated out during koalinitization.

关键词： m 类型四个效果改变的花岗石 g。Abu garadi 砍地区中央东方沙漠埃及

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Petrological and mineralogical characteristics of younger granites and pegmatites in the Wadi Haleifiya area, southeastern Sinai, Egypt

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Chinese Journal Of geochemistry 2011年第3期30卷 304-316页

作者： el gharbawy R.I. el feky m.g. el galy m.m. el maadawy W.m. Faculty of Science Ain Shams Univeristy Cairo Egypt Nuclear materials Authority P.O. Box 030 Maadi Egypt

This study is concerned with the radioactivity and mineralogy of the younger granites and pegmatites in the Wadi Haleifiya area, southeastern Sinai Peninsula, Egypt. The area is occupied by metasediments, m.g.atites, older and younger granites. most of these rocks, especially granites, are dissected by mafic and felsic dykes as well as pegmatites. The younger granites are represented by three main varieties: monzogranites, syenogranites and alkali feldspar granites. The monzogranite consists essentially of quartz, plagioclase, potash feldspar and biotite with minor musco-vite. Iron oxide, titanite, zircon and allanite are the main accessory minerals. Syenogranite is massive, medium- to coarse-grained and commonly exhibits equigranular and hypidiomorphic textures. It is made up essentially of potash feldspar, quartz, plagioclase and biotite. Iron oxides, allanite, epidote, titanite, and zircon are accessory minerals. The alkali feldspar granite consists mainly of perthite, quartz, alkali amphibole (arfvedsonite and riebekite), biotite, sub-ordinate plagioclase and aegirine. Iron oxide, zircon and apatite are accessory minerals, whereas chlorite and sas-surite are secondary minerals. The altered monzogranite and pegmatite recorded high radioelement contents. The eU reaches up to 120 (av.=82×10-6) in the altered monzogranite and up to 55 (av.=27×10-6) in the pegmatites. The high radioactivity in the altered monzogranite is due to the presence of thorite, uranothorite and metamict zircon. In the pegmatites, it is re-lated to the presence of uranophane, uranothorite, thorite, zircon, samarskite, monazite, xenotime, m.g.etite, ilmen-ite, hematite and rutile.

关键词：二长花岗岩矿物学特征西奈半岛伟晶岩东南部岩石学埃及碱长花岗岩

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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)therm.g.ams,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 m.g.etocaloric effect and m.g.etic 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,m.g.etic,and m.g.etocaloric 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 antiferrom.g.etic with a second order m.g.etic transition at Neel temperature（TN=2.9 K）.Analysis of the m.g.etic 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 m.g.e tic moment ■,which is close to the theoretical value ■.The m.g.etic 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 m.g.itude of-ΔSmand RCP show that the EuRhO3compound could be a potential candidate to be used in cryogenic m.g.etic refrigeration.

关键词： Cryogenic m.g.etic refrigeration m.g.etic properties m.g.etocaloric 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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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.g.nBank 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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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.g.O),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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Dysprosium oxide,alumina,and graphene oxide reinforced polycaprolactone thin films:Thermal stability,morphology,and cell viability

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Journal of Rare Earths 2024年第7期42卷 1337-1343,I0005页

作者： mohamed Tharwat elabbasy mohamed R.Atteya mai A.Samak mousa Abdelrahman Tahani Almahmoud m.A.el-morsy A.A.menazea m.F.H.Abd el-Kader Department of Public Health College of Public Health and Health InformaticsUniversity of Ha'ilHa'il2440Saudi Arabia Food Control Department Faculty of Veterinary MedicineZagazig UniversityZagazig44519Egypt Department of Physical Therapy College of Applied Medical SciencesUniversity of Ha'ilHa'ilSaudi Arabia Department of Histology and Cell Biology Faculty of MedicineZagazig UniversityZagazig44519Egypt College of Nursing University of Ha'ilHa'ilSaudi Arabia College of Science and Humanities in Al-Kharj Physics DepartmentPlasma Technology and Material Science UnitPrince Sattam Bin Abdulaziz UniversityAl-kharj11942Saudi Arabia Physics Department Faculty of ScienceUniversity of DamiettaNew Damietta34517Egypt Spectroscopy Department Physics Research InstituteNational Research CentreDokki12622GizaEgypt Biophysics Department Faculty of ScienceCairo UniversityGizaEgypt

Developing a biomaterial for wound healing applications is still a ***,dysprosium oxide(Dy_(2)O_(3)),aluminum oxide(Al_(2)O_(3)),and graphene oxide(gO)were embedded in cast films based on polycaprolactone(PCL)to be examined for wound dressing *** techniques were used to characterize the fabricated films including X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),Raman,and scanning electron microscopy(SEm),besides their biological *** therm.g.avimetric analysis(TgA)exhibits high thermal stability as the scaffold weight decreases slightly to 98.6%after raising the temperature from room temperature to 280℃.The cell viability was investigated and it is shown that the viable cells grow up to approximately 93%at 75μg/***,the cell attachment shows excellent behavior as the cells attach on most of the surface of the modified PCL which shows high biocompatibility.

关键词： Wound healing Polycaprolactone Dy_(2)O_(3) Al_(2)O_(3) Biocompatible Rare earths

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