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Origin and geochemical characteristics of beryllium mineralization in the Zabara-Wadi el Gemal region,South Eastern Desert,Egypt

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Acta Geochimica 2024年第6期43卷 1105-1122页

作者： Gehad M.Saleh Farrage M.Khaleal Mohammed Z.el-Bialy mohamed S.Kamar Mokhles K.Azer mohamed M.Omar mohamed n.el dawy Ahmed Abdelaal el Saeed R.Lasheen nuclear Materials Authority El-MaadiP.O.Box 530CairoEgypt 2 Geology DepartmentFaculty of SciencePort Said UniversityPort Said 42522Egypt 3 Geological Sciences DepartmentNational Research CentreCairoEgypt 4 Environmental Sciences DepartmentFaculty of SciencePort Said UniversityPort Said 42522Egypt 5 Geology DepartmentFaculty of ScienceAl-Azhar UniversityP.O.Box 11884CairoEgypt

Beryl is the commercial source of beryllium and several varieties of it are valued as a *** contribute to understanding the mechanism of beryl formation,we carried out detailed geological,petrographical,and geochemical investigations on beryl mineralization occurrences in the Zabara-Wadi el Gemal(Z-WG)*** region is an nW-SE trending tract that includes six berylhosting *** green gem variety of beryl(emerald)is restricted to phlogopite schist,pegmatite,and quartz *** hexagonal emerald crystals are well-developed in phlogopite schist and *** gem variety emerald examined is sodic and *** contains high concentrations of chromophore transition.elements ordering Cr(up to 1511 ppm)>V(up to 242 ppm)>Sc(up to 245 ppm),giving rise to its vivid green color,refl ecting mafic-ultramafic source *** the investigated emeralds,the Sikait area contains the highest BeO(av.10.76wt.%)*** compositional variability of emeralds is most likely attributed to the contribution from the host *** is revealed by the examined emerald mineralization,for instance;the Abu Rusheid area(one of the best areas exposing rare metal-bearing granitoids)possesses the highest average of trace and REEs *** contrast,Um Kabu emerald has the highest contents of Co(av.20 ppm),ni(av.299 ppm),MgO(av.8.2wt.%),Fe_(2)O_(3)(av.3.12wt.%),and CaO(avg.3.4wt.%)relative to other areas,which may be linked to contribution of ultramafic rocks exposed *** proposed mechanism we suggest for emerald genesis is metasomatic interaction between felsic intrusions,that are enriched with K,na,Be,Li,and B,with mafic-ultramafic rocks that are enriched in Cr,V,Mg,Fe,and *** interaction is marked by the formation of phlogopite schist,the growth of emerald crystals,and desilicated pegmatite.

关键词： Beryl chemistry Emerald genesis Phlogopite schist Pegmatite Eastern Desert

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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

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Correction:A Lightweight Approach for Skin Lesion Detection through Optimal Features Fusion

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Computers, Materials & Continua 2025年第1期82卷 1459-1459页

作者： Khadija Manzoor Fiaz Majeed Ansar Siddique Talha Meraj Hafiz Tayyab Rauf Mohammed A.el-Meligy mohamed Sharaf Abd elatty E.Abd elgawad Department of Information Technology University of GujratGujrat50700Pakistan Department of Software Engineering University of GujratGujrat50700Pakistan Department of Computer Science COMSATS University Islamabad-Wah CampusWah Cantt47040Pakistan Independent Researcher BradfordBD80HSUK Advanced Manufacturing Institute King Saud UniversityRiyadh11421Saudi Arabia Department of Industrial Engineering College of EngineeringKing Saud UniversityRiyadh11421Saudi Arabia

In the article“A Lightweight Approach for Skin Lesion Detection through Optimal Features Fusion”by Khadija Manzoor,Fiaz Majeed,Ansar Siddique,Talha Meraj,Hafiz Tayyab Rauf,Mohammed ***-Meligy,mohamed Sharaf,Abd elatty *** elgawad Computers,Materials&Continua,2022,Vol.70,no.1,pp.1617–***:10.32604/cmc.2022.018621,URL:https://***/cmc/v70n1/44361,there was an error regarding the affiliation for the author Hafiz Tayyab *** of“Centre for Smart Systems,AI and Cybersecurity,Staffordshire University,Stoke-on-Trent,UK”,the affiliation should be“Independent Researcher,Bradford,BD80HS,UK”.

关键词： Fusion Skin Feature

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On the Gosper’s q-constant Ⅱ_q

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Acta Mathematica Sinica,English Series 2018年第11期34卷 1755-1764页

作者： mohamed el BACHRAOUI Department Mathematical Sciences UAE University

Gosper introduced the functions sinq z and cosq z as q-analogues for the trigonometric functions sin z and cos z respectively. He stated a variety of identities involving these two q-trigonometric functions along with certain constants denoted by Πqn （n ∈ n）. Gosper noticed that all his formulas on these constants have more than two of the Πqn. So, it is natural to raise the question of establishing identities involving only two of the Πqn. In this paper, our main goal is to give examples of such formulas in only two Πqn.

关键词： q-trigonometric functions elliptic functions theta function identities

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Innovative surfactant of Gemini-type for dissolution mitigation of steel in pickling HCl medium

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Chinese Journal of Chemical Engineering 2021年第6期34卷 125-133页

作者： Medhat Kamel mohamed Hegazy Salah Rashwan mohamed el Kotb Department of Chemistry Faculty of ScienceSuez Canal UniversityIsmailia 41522Egypt Egyptian Petroleum Research Institute(EPRI) Nasr CityCairo 11727Egypt

A new surfactant of Gemini-type,n,n'-((phthylbis(oxy))bis(ethane-2,1-diyl))bis(n,n-dimethyldodecan-1-aminium bromide)is prepped&*** dissolution suppression impact of the new compound on steel is performed in 1 mol·L^(-1)HCl environment by means of chemical and electrochemical *** prepared surfactant is an agreeable dissolution inhibitor for *** mitigation efficacy rises with the quantity of the *** surfactant belongs to inhibitors of *** adsorption of the synthesized compound followed the Langmuir's *** negative magnitudes of bothΔG_(ads)^(θ) andΔH^(adsθ)indicate that the adsorption process proceeds from its own accord and *** mechanism of adsorption is elucidated by scanning *** is established that the transfer resistance(R_(ct))value rose,where the value of the phase element(CPE)reduced with the amount of synthesized *** to the experimental data arrived by surface tension measurements,the prepared compound is a powerful active agent at the air/water boundary.

关键词： Innovative Gemini surfactant Synthesis Dissolution mitigation Steel Pickling HCl media

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neoproterozoic Tectonic Events of Egypt

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Acta Geologica Sinica(English Edition) 2021年第4期95卷 1366-1405页

作者： mohamed ABD el-WAHED Zakaria HAMIMI Geology Department Faculty of ScienceTanta UniversityTanta 31527Egypt Department of Geology Faulty of ScienceBen ha UniversityBenha 13518Egypt

The Egyptian nubian Shield(EnS)represents the northwestern part of the Arabian-nubian Shield and the northern extension of the East African *** EnS is regarded as being formed due to northward-directed escape *** is characterized by mild accretion and suture zones dominated by major strike-slip zones with a commonly sinistral sense of movement;some shear zones display a dextral sense of *** is dominated by gneisses and migmatites in the south,arc volcaniclastic metasediments and highly dismembered ophiolites in the central parts,whereas its northern part is dominated by late-to post-tectonic *** southern Sinai,the neoproterozoic rocks are grouped into four complexes,namely Feiran–Solaf,Sa’al–Zaghra,Kid and *** EnS ophiolites were formed between 730–750 Ma,mainly in a supra-subduction zone *** EnS has undergone a neoproterozoic deformation history involving three successive phases:(1)Early n–S shortening phase(D1),(2)Syn-accretionary phase(D2)and(3)Post-accretionary phase(D3).The initial island-arc stage(780–730 Ma)is a n–S shortening phase initiated by collision between the Eastern Desert tectonic terrane to the north with both the Gebeit and Gabgaba terranes to the south(830–720 Ma).During the arc-splitting and back-arc spreading stage(730–620),voluminous syn-tectonic granitoids intruded into the EnS(750–610 Ma).The E–W-directed compressional/transpressional phase(620–450 Ma)led to the overall uplift of the central part of the EnS and consequently the development and exhumation of the core complexes in oblique convergent *** E–W intense shortening deformation resulted also in the formation of nW-and nE-striking sinistral and dextral strike-slip shear zones,*** latest periods of the E–W-directed compressional/transpressional regime were characterized by deposition of the molasse-type Hammamat Sediments unconformably over the Dokhan Volcanics,or interbedded with *** combined thrusting,folding and sin

关键词： neoproterozoic deformation n–S shortening syn-accretionary phase post-accretionary phase Egyptian nubian Shield

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Epi- and endobiont faunal communities on an Egyptian Mediterranean rocky shore: species composition and their competition for space

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Journal of Oceanology and Limnology 2021年第1期39卷 198-207页

作者： Magdy el HEDEnY mohamed RASHWAn Sebastián RICHIAnO Saleh AL FARRAJ Ghada AL BASHER Department of Geology Faculty of ScienceAlexandria UniversityAlexandria 21568Egypt Department of Biological and Geological Sciences Faculty of EducationAlexandria UniversityAlexandria 14037Egypt Instituto Patagónico de Geología y Paleontología(COnICET-CEnPAT) Puerto Madryn 9120Argentina Department of Zoology College of SciencesKing Saud UniversityP.O.Box 2455Riyadh 11451Saudi Arabia

The exposed calcareous rocky area of the Abu Qir Headland,east of Alexandria,Egypt which range from coarse grains,through pebbles,cobbles,and boulders to rocky platforms,was signifi cantly colonized by sclerobionts(epibionts and endobionts).The epibiont species diversity was comparatively higher than that of *** communities included bryozoans(the anascan-grade cheilostome Bifl ustra savartii),serpulid(Hydroides elegans,Spirobranchus ***,Vermiliopsis striaticeps and Protula or Apomatus)and spirorbid(Spirorbis)wormtubes,and balanoid barnacles(Amphibalanus amphitrite,Balanus trigonus,and Perforatus perforatus).The cheilostome bryozoan colonies,which developed extensive sheets,proliferated on the study rocky shore either encrusting the bioeroded basement directly,or encrusting other epilithic taxa,particularly balanoid barnacles and serpulid *** displayed a remarkable marginal competitive interaction(overgrowth and stand-off)for space on the study rocky *** the other hand,endobionts were not well represented on the studied rocky shore *** was possible to identify three ichnotaxa:Gastrochaenolites,Maeandropolydora,and *** fi ndings documented represent a signifi cant contribution to our knowledge of sclerobionts composition,sequence of their colonization and/or bioerosion,and their mutual relationships on the intertidal rocky shore of the Abu Qir Headland.

关键词： sclerobionts encrustation bioerosion Mediterranean Egypt

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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(nnates and the velocity *** 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

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Excimer laser 6^(th)generation:state of the art and refractive surgical outcomes

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Eye and Vision 2015年第1期2卷 44-52页

作者： mohamed el Bahrawy Jorge L Alió Vissum Corporación Alicante AlicanteSpain Division of Ophthalmology Universidad Miguel HernándezAlicanteSpain Clinical research fellow in Vissum Corporación Alicante Universidad Miguel HernándezAlicanteSpain Avda de Denia s/n Edificio Vissum03016 AlicanteSpain

After nearly three decades of innovation in excimer laser,today we are presented with a state of the art generation targeting minimally invasive refractive surgery with high speed laser,faster trackers,pupil monitoring systems and better customization *** systems are capable of delivering better treatments with less induced postoperative high order *** results reported by many authors had confirmed the superiority in efficiency and safety profiles of this generation compared to previous ***,current technology is facing major challenges in the correction of high hyperopic errors and in presbyopic treatments,with upgrades in ablation centration and thermal control needed,which will ensure better biomechanical results,as a step closer to perfection in refractive surgery.

关键词： Refractive surgery Excimer laser 6^(th)Generation

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Potential generated by a massive inhomogeneous straight segment

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Research in Astronomy and Astrophysics 2011年第3期11卷 345-352页

作者： nour-Eddine najid el Haj elourabi mohamed Zegoumou Equipe Mécanique Statistique et Astronomie-Laboratoire de Physique Théorique et Appliquée Université Hassan Ⅱ Ain Chock-Faculté des Sciences Ain Chock BP 5366 Maarif Casablanca Morocco

The discoveries of binary asteroids have opened an important new field of research concerning the calculation of potential generated by irregular *** of them have an.elongated shape.A simple model to describe the motion of a test particle in that kind of potential requires consideration of a finite homogeneous straight *** construct this model by adding an inhomogeneous distribution of mass. To be consistent with the geometrical shape of the asteroid,we explore a parabolic profile of the *** establish the closed analytical form of the potential generated by this inhomogeneous massive *** study of the dynamical behavior is fulfilled by the use of Lagrangian formulation,which allows us to calculate some two and three dimensional orbits.

关键词： asteroids—potential—inhomogeneous distribution

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