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Journal of Power and Energy Engineering 2024年第9期12卷 37-49页

作者： mostafa I. Saleh Gaber el-Saady Ali m. Yousef el-Noby A. Ibrahim Alfanar Company Mecca Saudi Arabia Department of electrical Engineering Faculty of Engineering Asyut University Asyut Egypt

Distributed generators now is widely used in electrical power networks, in some cases it works seasonally, and some types works at special weather conditions like photo voltaic systems and wind energy, and due to this continuous changes in generation condition, the fault current level in network will be affected, this changes in fault current level will affect in the coordination between protection relays and to keep the coordination at right way, an adaptive protection system is required that can adaptive its setting according to generation changes, the fault current level in each case is evaluated using ETAP software, and the required relay setting in each case is also evaluated using Grey Wolf Optimizer (GWO) algorithm, and to select suitable setting which required in each condition, to select the active setting group of protection relay according to generation capacity, central protection unite can be used, and to improve protection stability and minimizing relays tripping time, a proposed method for selecting suitable backup relay is used, which leads to decrease relays tripping time and increase system stability, output settings for relays in all cases achieved our constrains.

关键词： Directional Overcurrent Relay Protection Coordination Distributed Generators Central Protection Unite multiple Setting Group Protection Relay

Softζ-Rough Set and Its Applications in Decision making of Coronavirus

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Computers, materials & Continua 2022年第1期70卷 267-285页

作者： m.A.el Safty Samirah Al Zahrani m.K.el-Bably m.el Sayed Department of mathematics and Statistics College of ScienceTaif UniversityTaif21944Saudi Arabia Department of mathematics Faculty of ScienceTanta UniversityTantaEgypt Department of mathematics College of Science and ArtsNajran UniversityNajran66445Saudi Arabia

In this paper,we present a proposed method for generating a soft rough approximation as a modification and generalization of Zhaowen et *** were obtained between our approach and the previous study and ***,an application on Coronavirus(COVID-19)has been presented,illustrated using our proposed concept,and some influencing results for symptoms of Coronavirus patients have been ***,following these concepts,we construct an algorithm and apply it to a decision-making problem to demonstrate the applicability of our proposed ***,a proposed approach that competes with others has been obtained,as well as realistic results for patients with ***,we used mATLAB programming to obtain the results;these results are consistent with those of theWorld Health Organization and an accurate proposal competing with the method of Zhaowen et *** been ***,it is recommended that our proposed concept be used in future decision making.

关键词： Soft set soft rough set softζrough set COVID-19 intelligence discovery decision making

First-principles prediction of the magnetism of 4f rare-earth-metal-doped wurtzite zinc oxide

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Journal of Rare Earths 2014年第8期32卷 715-721页

作者： A.G.el Hachimi H.Zaari A.Benyoussef m.el Yadari A.el Kenz Laboratoire de magnétisme et Physique des Hautes Energies LMPHE (URAC 12) Département de Physique B.P.1014 Faculté des SciencesUniversité Mohammed V-Agdal Institut of Nanomaterials and Nanotechnology Hassan II Academy of Science and Technology Department of Science Moulay Ismail University Faculté Polydisciplinaire

electronic structure and magnetic properties of wurtzite ZnO semiconductor doped with rare earth （RE=La, Ce, Pr, Pm, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm and Yb） atoms were studied using spin-polarized density functional theory based on the full-potential linear augmented plane wave （FP-LAPW） method as implemented in the Wien2k code. In this approach the generalized gradient approximation （GGA） was used for the exchange-correlation （XC） potential. Our results showed that the substitution of RE ions in ZnO induced spins polarized localized states in the band gap. moreover, the studied DmSs compounds retained half metallicity at dopant concentration x=0.625%for most of the studied elements, with 100%spin polarization at the Fermi level （EF）. The total magnetic moments of these compounds existed due to RE 4f states present at EF, while small induced magnetic moments existed on other non-magnetic atoms as well. Finally, the energy difference between far and near configurations was investigated. It was found that the room temperature ferromagnetism was possible for RE-doped ZnO at near configuration. Since the RE-RE separation was long enough （far configuration） for magnetic coupling, the system became paramagnetic or antiferromagnetic ground state.

关键词： ZnO rare earths ferromagnetism DmS electronic structure magnetic properties half-metallic RE-doped ZnO FP-LAPW method density functional theory

Ginseng ameliorates pulmonary toxicity induced by silicon dioxide nanoparticles in rats

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Asian Pacific Journal of Tropical Biomedicine 2021年第6期11卷 254-262页

作者： Raghda A.el-Sayed Fatma m.el-Demerdash mohammed A.el-magd Department of Environmental Studies Institute of Graduate Studies and ResearchAlexandria UniversityEgypt Department of Anatomy Faculty of Veterinary MedicineKafrelsheikh UniversityEgypt

Objective:To investigate the protective and therapeutic role of ginseng against silicon dioxide nanoparticles(SiO2NPs)-induced toxicity in the ***:Sixty male rats were divided into five groups(n=12/group);group 1 was used as a control,group 2 received ginseng,group 3 was treated with SiO2NPs,and group 4 was pretreated with ginseng one week before SiO2NPs,while group 5 was given SiO2NPs one week before supplementation with *** were treated with both ginseng and SiO2NPs orally for five ***-time PCR was used to measure gene ***,DNA damage and cell cycle changes were determined by comet assay and flow cytometry,*** study was also done to assess the effect of ginseng on SiO2NPs-induced ***:SiO2NPs increased lipid peroxidation and decreased the activities of antioxidant ***2NPs induced apoptosis in lung tissues as revealed by upregulation of Bax and caspase 3 and downregulation of Bcl-2 as well as the induction of DNA ***2NPs also caused inflammation as indicated by upregulation of the inflammation-related genes[interleukin 1 beta(IL-1β),tumor necrosis factor-alpha(TNF-α),nuclear factor kappa B(NF-κB),cyclooxygenase 2(COX2),and transforming growth factor-beta 1(TGFβ1)]as well as cell cycle arrest in the G0/G1 phase of lung ***,histopathological examination proved the biochemical and molecular perturbations that occurred due to SiO2NPs ***,ginseng alleviated SiO2NPs-induced toxicity in rat ***:Ginseng has a potent preventive and therapeutic effect and could be used in the treatment of SiO2NPs-induced pulmonary toxicity.

关键词： Silicon dioxide nanoparticles Ginseng Oxidative stress Inflammation Pulmonary toxicity

Tracking the Ti^(4+)substitution in phlogopite by spectroscopic imaging:A tool for unravelling the growth of micas at HP-HT conditions

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Geoscience Frontiers 2024年第3期15卷 1-13页

作者： G.Della Ventura N.el moutaouakkil B.Boukili S.Bernardini A.Sodo L.Pronti m.Cestelli-Guidi F.Holtz F.Lucci Dipartimento di Scienze UniversitàRoma TreRomaItaly INFN-LNF via Fermi 200040 FrascatiRomaItaly INGV Via di Vigna Murata 60500143 RomaItaly Laboratory of Géosciences Water and Environment.Department of Earth Sciences.Faculty of SciencesUniversity Mohammed VRabatMorocco Leibnitz Universität Hannover Institute of MineralogyCallinstr 330167 HannoverGermany Dipartimento di Scienze della Terra e Geoambientali Universitàdi Bari“Aldo Moro”BariItaly

Phlogopite solid-solutions have a wide pressure-temperature(P-T)stability field and are ubiquitous in a wide variety of geological settings,from deep lithosphere magmatic environments to upper crust metamorphic *** composition represents therefore a valuable physical-chemical archive and may provide important information regarding its crystallization and the petrogenesis of the *** this paper we examine the phlogopite phenocrysts from the well-known Fort Regent mica-bearing lamprophyre minette from ***(Island of Jersey,UK).Phlogopite phenocrystals from lamprophyres generally show normal-step and continuous compositional zoning,however those from the Fort Regent minette show a peculiar texture characterized by dark brown high-Ti(average TiO_(2)≈8.5 wt.%)cores enveloped by euhedral low-to mid-amplitude zonation due to oscillatory contents in Ti,Fe and ***-barometry modelling based on biotite-only composition yields relatively high P-T estimates(T≈970±54℃at P≈0.73±0.13 GPa)for cores whereas lower values(T≈790±54℃at P≈0.29±0.13 GPa)are obtained for the outer *** temperatures(T≈1075±54℃)but extremely high and anomalous pressure values(P≈1.82±0.13 GPa)are obtained for the yellowish inner *** combination of electron micro probe(EmP)analysis and single-crystal infra-red(FTIR)imaging in the OH-stretching region shows that the exceptional and oscillatory Ti contents are due to the Ti-vacancy substitution,typical of crystallization and growth processes of HP/HT *** imaging provides additional insight for this process,confirming the dominant dioctahedral nature for the Ti-Fe-rich cores and outer *** of thermobaric estimates obtained from the phlogopite compositiononly model,based on the fine-scale compositional evolution,shows that pressure-temperature values from low-Ti high-mg domains should be carefully evaluated because the substitution mechanisms during the dark mica growth are not univocal

关键词： Ti-phlogopite Jersey minette(UK) Ti-substitution FTIR imaging Raman imaging Thermobarometric modelling

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

Geochemistry of lamprophyre dykes, Wadi Sikait area, South Eastern Desert, Egypt

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Chinese Journal Of Geochemistry 2011年第3期30卷 323-331页

作者： Ibrahim m.el-Ahmadi Ragab A.Ahmed Nuclear materials Authority el-maadi P.O.Box 530 Cairo Egypt

The Wadi Sikait area lies at about 95 km southwest of marsa Alam City along the Red Sea Coast, Eastern Desert, Egypt. It is occupied by Precambrian rocks of ophiolitic mélange, metamorphosed sandstones (mSS), gab-bros and monzogranites which were later intruded by lamprophyre dykes and quartz veins. The lamprophyre dykes were extruded in NW-SE and NE-SW trends cutting monzogranites and metamor-phosed sandstones. The lamprophyres are porphyritic and composed of clinopyroxene, olivine and amphibole phenocrysts enclosed in a fine-grained groundmass of clinopyroxene, amphibole, opaque and lithium mica. The al-teration products are represented by amphibole (tremolite-actinolite and hornblende), carbonate, epidote, chlorite, iddingsite, clay minerals, limonite and serpentine. The Sikait lamprophyre dykes can be classified as alkaline lamprophyres characterized by silica contents rang-ing from 41.65 wt% to 50.88 wt% and Na2O>K2O. They are enriched in LILE, LREE and HFSE, but strongly de-pleted in compatible elements such as Cr and Ni relative to the primitive mantle. Sikait lamprophyres have moderate Zr/Hf (35.6-52.8) and Nb/Ta (20.5-22.5) ratios. most of these features are attributed to the origin of these dykes from the metasomatized mantle affected by subduction-related fluid. These lamprophyres are compositionally similar to Salu lamprophyres in eastern China. The Sikait lamprophyre samples have high LREE (320×10-6-419×10-6) relative to HREE (20×10-6-33×10-6) with ratios (LREE/HREE=11.6-18.7) and no negative Eu anomaly (Eu/Eu*=0.9-1.04). The relative presence of posi-tive Ce anomaly (Ce/Ce*=1.04) in lamprophyre samples suggests the oxidizing condition under which the REEs were precipitated due to the common occurrence of fluorite and apatite.

关键词：煌斑岩地球化学特征岩脉沙漠埃及二长花岗岩单斜辉石蛇绿混杂岩

Physical Studies of Some Hydrazinobenzoic Acid Complexes

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Journal of materials Science & Technology 2005年第1期21卷 140-144页

作者： m.G.Abd el Wahed S.Abd el Wanees m.el Gamel S.Abd el Haleem Faculty of Science Zagazig University Zagazig EgyptFaculty of Science Zagazig University Zagazig EgyptFaculty of Science Zagazig University Zagazig EgyptFaculty of Science Zagazig University Zagazig Egypt

The stability constants of complexes of 2-hydrazinobenzoic acid and 4-hydrazinobenzoic acid with Ni (Ⅱ), Cu (Ⅱ), Zn (Ⅱ), Cd (Ⅱ), and Hg (Ⅱ) were determined potentiometricaIly at different temperatures. The thermodynamic parameters, △G0, △H0, and △S0 were calculated and proved that the complexation process is spontaneous and endothermic. The thermodynamic functions were analyzed in terms of electrostatic and non-electrostatic components and the results reveal that ionic bonds are formed between the studied ligands and metal ions. Conductometric titration was shown that the stoichiometry of the formed complexes are m:L and m:2L. The structure of the prepared solid complexes was characterized using IR, 1H NmR, 13C NmR spectroscopies as well as X-ray diffraction technique. Finally electrical conductivity of the ligands and their copper complexes was measured and shown that the ligands have a semiconductor behaviour.

关键词： Potentiometric titration Stability constants Thermodynamic parameters Structure of metal complexes

modelling the monthly hydrological balance using Soil and Water Assessment Tool(SWAT)model:A case study of the Wadi mina upstream watershed

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Journal of Groundwater Science and Engineering 2024年第2期12卷 161-177页

作者： Hanane mebarki Noureddine maref mohammed el-Amine Dris Civil Engineering and Environmental Laboratory(LGCE) University of Djillali LiabèsFaculty of TechnologyHydraulics departmentBen M'Hidi districtP.O.Box 8922000Sidi Bel AbbèsAlgeria.

modelling the hydrological balance in semi-arid zones is essential for effective water resource management,encompassing both surface water and *** study aims to model the monthly hydrological water cycle in the Wadi mina upstream watershed(northwest Algeria)by applying the Soil and Water Assessment Tool(SWAT)hydrological *** modelling integrates spatial data such as the Digital elevation model(DEm),land use,soil types and various meteorological parameters including precipitation,maximum and minimum temperatures,relative humidity,solar radiation and wind *** SWAT model was calibrated and validated using data from January 2012 to December 2014,with a calibra-tion period from January 2012 to August 2013 and a validation period from September 2013 to December *** and parameter calibration were conducted using the SWAT-SA program,and model performance evaluation relied on comparing the observed discharge at the outlet of the basin with model-simulated discharge,assessed through statistical coefficients including Nash-Sutcliffe Efficiency(NSE),coefficient of determination(R2)and Percent Bias(PBAIS).Calibration results indicated favourable objec-tive function values(NSE=0.79,R2=0.93,PBAIS=-8.53%),although a slight decrease was observed during validation(NSE=0.69,R2=0.86,and PBAIS=-11.41%).The application of the SWAT model to the Wadi mina upstream watershed highlighted its utility in simulating the spatial distribution of different components of the hydrological balance in this *** SWAT model revealed that approximately 71%of the precipitation in the basin evaporates,while only 29%contributes to surface runoff or infiltration into the soil.

关键词： SWAT model Performance Parameters Runoff Groundwater Wadi

Decision making on Fuzzy Soft Simply Continuous of Fuzzy Soft multi-Function

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Computer Systems Science & Engineering 2022年第3期40卷 881-894页

作者： m.A.el Safty Samirah Al Zahrani Ansari Saleh Ahmar m.el Sayed Department of mathematics and Statistics College of ScienceTaif UniversityTaif 21944Saudi Arabia Department of Statistics Faculty of Mathematics and Natural SciencesUniversitas Negeri MakassarMakassar 90223Indonesia Department of mathematics College of Science and ArtsNajran UniversityNajranSaudi Arabia

Real world applications are dealing now with a huge amount of data,especially in the area of high dimensional *** this article,we depict the simplyupper,the simplylower continuous,we get several characteristics and other properties with respect to upper and lower simply-continuous soft *** also investigate the relationship between soft-continuous,simply-continuous *** also implement fuzzy soft multifunction between fuzzy soft topological spaces which is Akdag’s generation of the *** are introducing a new class of soft open sets,namely soft simplyopen set deduce from soft topology,and we are using it to implement the new approximation space called soft multi-function approach *** for approximation based on a simplyopen *** world must adopt modern studies in order to confront ***,we presented a new decision proposal in this article,compared our proposed approach to the soft relationship introduced by approximation of Xueyou,and concluded that our approach is *** also used our proposal in the medical application that was studied in this paper.

关键词： Soft multifunction soft simplylower soft simplyupper approximation upper inverse of a fuzzy soft multifunction intelligence discovery decision making