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mineralogy and radioactivity of pegmatites from South Wadi Khuda area,Eastern Desert,Egypt

Chinese Journal Of geochemistry 2010年第4期29卷 343-354页

作者： mohamed F.Raslan mohamed A.Ali mohamed g.el-Feky Nuclear materials Authority P.O.Box 530El MaadiCairoEgypt

Radioactive minerals in pegmatites associated with granitic rocks are commonly encountered in the south of the Wadi Khuda area and found as dyke-like and small *** are observed within garnet-muscovite granites near the contact with older *** surveys indicated that the studied pegmatites vary in dimensions ranging from 2 to 10 m in width and from 10 to 500 m in *** are composed mainly of intergrowth of milky quartz,reddish-pink K-feldspar and plagioclase together with small pockets of *** radiometric measurements indicated that radioactivity in pegmatites is more than twice that of their enclosing country *** measurements revealed that the average contents of U and Th increase gradually from rocks of dioritic to granodioritic composition(1.5×10-6 U and 4.3×10-6 Th) and increase significantly in biotite granites(5.8×10-6 U and 15.2×10-6 Th) but drastically decrease in muscovite granites(2.2×10-6 U and 5.6×10-6 Th).The average contents of U and Th of anomalous pegmatites are 95.3×10-6 and 116.9×10-6,respectively,indicating their uraniferous *** the south of the Wadi Khuda area,pegmatites are low in average Th/U(1.4) and high in average U/K(35.6),which suggests that uranium concentrating processes did not affect the pegmatites,indicating poor *** investigations of the studied pegmatites revealed the presence of secondary uranium minerals(kasolite and autunite),in addition to zircon,thorite,apatite,garnet and *** and secondary radioactive mineralizations indicated that the mineralization is not only magmatic,but also *** microprobe analyses showed distinct cryptic chemical zoning within thorite where UO2 decreases from core to *** feature in thorite is sporadic,suggesting non-uniform redistributions of UO2 within thorite during magmatic processes.

关键词：放射性核素伟晶岩矿物学黑云母花岗岩平均含量沙漠埃及电子探针分析

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Hyperparameter Tuned Deep Learning Enabled Cyberbullying Classification in Social media

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Computers, materials & Continua 2022年第12期73卷 5011-5024页

作者： mesfer Al Duhayyim Heba g.mohamed Saud S.Alotaibi Hany mahgoub Abdullah mohamed Abdelwahed motwakel Abu Sarwar Zamani mohamed I.eldesouki Department of Computer Science College of Sciences and Humanities-AflajPrince Sattam bin Abdulaziz UniversitySaudi Arabia Department of electrical Engineering College of EngineeringPrincess Nourah Bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of Information Systems College of Computing and Information SystemUmm Al-Qura UniversitySaudi Arabia Department of Computer Science College of Science&Art at MahayilKing Khalid UniversityMuhayel AseerSaudi Arabia Faculty of Computers and Information Computer Science DepartmentMenoufia UniversityEgypt Research Centre Future University in EgyptNew Cairo11845Egypt Department of Computer and Self Development Preparatory Year DeanshipPrince Sattam bin Abdulaziz UniversityAl-KharjSaudi Arabia Department of Information System College of Computer Engineering and SciencesPrince Sattam bin Abdulaziz UniversityAl KharjSaudi Arabia

Cyberbullying(CB)is a challenging issue in social media and it becomes important to effectively identify the occurrence of *** recently developed deep learning(DL)models pave the way to design CB classifier models with maximum *** the same time,optimal hyperparameter tuning process plays a vital role to enhance overall *** study introduces a Teacher Learning genetic Optimization with Deep Learning Enabled Cyberbullying Classification(TLgODL-CBC)model in Social *** proposed TLgODL-CBC model intends to identify the existence and non-existence of CB in social media ***,the input data is cleaned and pre-processed to make it compatible for further *** by,independent recurrent autoencoder(IRAE)model is utilized for the recognition and classification of ***,the TLgO algorithm is used to optimally adjust the parameters related to the IRAE model and shows the novelty of the *** assuring the improved outcomes of the TLgODLCBC approach,a wide range of simulations are executed and the outcomes are investigated under several *** simulation outcomes make sure the improvements of the TLgODL-CBC model over recent approaches.

关键词： Social media deep learning cyberbullying cybersecurity hyperparameter optimization

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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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Fe_(3)O_(4)-carbon spheres core–shell supported palladium nanoparticles:A robust and recyclable catalyst for suzuki coupling reaction

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Chinese Journal of Chemical Engineering 2022年第11期51卷 75-85页

作者： mohamed A.Almaradhi Hassan m.A.Hassan mosaed S.Alhumaimess Department of Chemistry College of ScienceJouf UniversityPO Box 2014SakakaSaudi Arabia

Suzuki-miyaura(S-m)is regarded the most powerful way for synthesis biaryls,triaryls,or incorporating of substituted aryl moieties in organic preparation by the cross-coupling of aryl boronic acid with aryl halides using the Pd *** work reports the combining of the hydrothermal and microwaveassisted protocol to convert the glucose to magnetic carbon spheres(Fe_(3)O_(4)-CSPs)decorated with Pd nanoparticles(NPs)as the catalyst for Suzuki-miyaura cross-coupling *** physicochemical properties in the produced composite were examined using FESEm,HRTEm,nitrogen isotherms,Raman spectroscopy,FTIR,XPS,and *** as-fabricated composite Pd/Fe_(3)O_(4)-CSPs is mostly spherical with a core–shell structure and possesses a great surface area of 253.2 m^(2).g^(-1).Its catalytic performance demonstrates that the composite has excellent stability and high tolerance Suzuki-miyaura crosscoupling reactions in 30 min at 80℃.Both activated and deactivated aryl halides provided excellent *** as-fabricated catalyst was recycled for up to four catalytic cycles without a substantial decline in ***,this research offers a facile roadmap for synthesizing Pd/Fe_(3)O_(4)-CSPs composites and promoting the practical implementation of Pd/Fe_(3)O_(4)-CSPs catalysts for organic transformation processes.

关键词： Heterogeneous catalysis Aryl halide Suzuki coupling Palladium nanoparticles Carbon spheres

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Investigating energy policies to boost grid-connected rooftop solar PV in Sudan

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Clean Energy 2023年第5期7卷 994-1005页

作者： Tarig Z.Ahmed Ayah mohamed mawahib eltayeb Ahmed Ahmed Osman elamin Abdalgader mohamed g.Hassan-Sayed Cambridge Institute for Sustainability Leadership(CISL) University of CambridgeCambridgeCB21QAUK Energy and Climate Change Division Faculty of Engineering and Physical ScienceThe University of SouthamptonSouthamptonSO171BJUK Institute of Engineering Research and material Technology National Centre for ResearchKhartoumSudan/University of KhartoumSudan University of California Davis1 Shields AveDavisCA 95616USA School of Chemistry Faculty of Engineering and Physical SciencesThe University of SouthamptonSouthamptonSO171BJUK

grid-connected rooftop solar photovoltaic(PV)systems can reduce the energy demand from the grid and significantly increase the power available to ***,rooftop solar PV has not yet been widely adopted in many sub-Saharan African countries,such as Sudan,although they are endowed with high solar radiation and in dire need of additional *** paper investigates risks and policies to increase grid-connected rooftop solar PV adoption in Sudan.A simplified United Nations Development Program Derisking Renewable Energy Investment framework is adopted to investigate this over three *** Stage 1,a list of risks and barriers was produced based on a literature review of solar PV studies in Sudan and interviews with nine *** was the risk most often mentioned(eight times from nine interviewees),followed by concerns about poor utility grid *** Stage 2,policy de-risking instruments and financial de-risking instruments were listed to overcome the *** include the intro-duction of net metering,the use of a third-party organization to monitor policy implementation,upgrade of the grid infrastructure,public awareness campaigns and energy-saving *** Stage 3,the levelized cost of electricity was estimated for a typical 2-kW rooftop PV system without policies(0.11$/kWh)and with a net-metering policy(0.07$/kWh).

关键词： energy policy rooftop solar PV Sudan energy poverty sustainable development photovoltaics

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Amination of biochar surface from watermelon peel for toxic chromium removal enhancement

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Chinese Journal of Chemical Engineering 2021年第8期34卷 199-222页

作者： mohamed A.el-Nemr Ibrahim m.A.Ismail Nabil m.Abdelmonem Ahmed el Nemr Safaa Ragab Department of Chemical Engineering Faculty of EngineeringCairo UniversityGizaEgypt Renewable Energy Program Zewail City of Science and TechnologyEgypt Environmental Division National Institute of Oceanography and FisheriesKayet BeyEl-AnfoushyAlexandriaEgypt

Watermelon peel residues were used to produce a new biochar by dehydration *** new biochar has undergone two methods of chemical modification and the effect of this chemical modification on its ability to adsorb Cr(VI)ions from aqueous solution has been *** biochars,melon-B,melon-BO-NH_(2) and melon-BO-TETA,were made from watermelon peel via dehydration with 50%sulfuric acid to give melon-B followed by oxidation with ozone and amination using ammonium hydroxide to give melon-BO-NH_(2) or Triethylenetetramine(TETA)to give *** prepared biochars were characterized by BET,BJH,SEm,FT-IR,TgA,DSC and EDAX *** highest removal percentage of Cr(VI)ions was 69%for melon-B,98%for melon-BO-NH_(2) and 99%for melon-BO-TETA biochars of 100 mg·L^(−1) Cr(VI)ions initial concentration and 1.0 g·L^(−1) adsorbents *** unmodified biochar(melon-B)and modified biochars(melon-BO-NH_(2) and melon-BO-TETA)had maximum adsorption capacities(Q_(m))of 72.46,123.46,and 333.33 mg·g^(−1),*** amination of biochar reduced the pore size of modified biochar,whereas the surface area was *** obtained data of isotherm models were tested using different error function *** Freundlich,Tempkin and Langmuir isotherm models were best fitted to the experimental data of melon-B,melon-BO-NH_(2) and melon-BO-TETA,*** adsorption rate was primarily controlled by pseudo-second–order rate ***,the functional groups interactions are important for adsorption mechanisms and expected to control the adsorption *** adsorption for the melon-B,melon-BO-NH_(2) and melon-BO-TETA could be explained for acid–base interaction and hydrogen bonding interaction.

关键词： Waste treatment Powder technology Citrullus lanatus Hexavalent chromium Biochar amination Adsorption

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Streptococcus peumoniae in an Egyptian urban community:incidence of erythromycin-resistance determinants and antibiotic susceptibility profile

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Asian Pacific Journal of Tropical medicine 2008年第4期1卷 20-23页

作者： Fatma abdelaziz Amer Eman mohamed elbehedy mohamed elahmady microbiology and Immunology Department Faculty of PharmacySinai UniversitySinaiEgypt microbiology & Immunology Department Faculty of MedicineZagazig UniversityZagazigEgypt

Objectives:To determine the incidence of resistance of Streptococcus(Strep).pneumoniae isolated in our locality to erythromycin,to screen for the two resistance determinants erm(B) and mef(A) genes,and to identify the susceptibility profile to commonly used ***:Samples were collected from patients attending the Outpatient Department of Zagazig University Hospital,Zagazig,Egypt,between February 2006 and march *** was identified by conventional *** to erythromycin and 15 antibiotics were identified by disc diffusion method,as outlined by CLSI.E-test was used for mIC determination of ***(B) and mef(A) genes were detected by ***:Eighty-one Strep. pneumoniae strains were ***- one of them(63%) were erythromycin-resistant,and mef(A) gene was the predominant resistance ***,imipenem and gatifloxacin had the best activity against the isolates,whereas tetracycline had the ***-two(51.85%) out of the 81 *** strains were ***:High incidence of resistance to erythromycin and multiple antimicrobials ***(A) was the principal erythromycin-resistance gene.

关键词： Strep,pneumoniae Erythromycin erm.(B) gene mef(A) gene Antibiotic resistance Egypt

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EJUSTCO:monte Carlo radiation transport code hybrid with ANN model for gamma-ray shielding simulation

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Nuclear Science and Techniques 2023年第9期34卷 155-176页

作者： Joseph Konadu Boahen Ahmed S.g.Khalil mohsen A.Hassan Samir A.elsagheer mohamed materials Science and Engineering Department School of Innovative Design EngineeringEgypt-Japan University of Science and Technology(E-JUST)179New Borg El-Arab CityEgypt Physics Department Environmental and Smart Technology GroupFaculty of ScienceFayoum UniversityFayoum 63514Egypt Faculty of Engineering Aswan UniversityAswanEgypt

gamma ray shielding is essential to ensure the safety of personnel and equipment in facilities and environments where radiation *** monte Carlo technique is vital for analyzing the gamma-ray shielding capabilities of *** this study,a simple monte Carlo code,EJUSTCO,is developed to cd simulate gamma radiation transport in shielding materials for academic *** code considers the photoelectric effect,Compton(incoherent)scattering,pair production,and photon annihilation as the dominant interaction mechanisms in the gamma radiation shielding *** reduction techniques,such as the Russian roulette,survival weighting,and exponential transformation,are incorporated into the code to improve computational *** the exponential transformation parameter typically requires trial and error as well as ***,a deep learning neural network is proposed as a viable method for predicting this parameter for the first *** model achieves an mSE of 0.00076752 and an R-value of *** exposure buildup factors and radiation dose rates due to the passage of gamma radiation with different source energies and varying thicknesses of lead,water,iron,concrete,and aluminum in single-,double-,and triple-layer material systems are validated by comparing the results with those of mCNP,ESg,ANS-6.4.3,mCBLD,mONTEREY mARK(m),PENelOPE,and *** errors of 5.6%,2.75%,and 10%are achieved for the exposure buildup factor in single-,double-,and triple-layer materials,respectively.A significant parameter that is not considered in similar studies is the gamma ray *** the EJUSTCO code,the total number and energy albedos have been *** results are compared with those of mCNP,FOTelP,and *** general,the EJUSTCO-developed code can be employed to assess the performance of radiation shielding materials because the validation results are consistent with theoretical,experimental,and literary results.

关键词： monte Carlo gamma rays Shielding Artificial neural network Simulation

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A new systematic firefly algorithm for forecasting the durability of reinforced recycled aggregate concrete

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Frontiers of Structural and Civil Engineering 2022年第3期16卷 329-346页

作者： Wafaa mohamed SHABAN Khalid elBAZ mohamed AmIN Ayat gamal ASHOUR Department of Civil and Environmental Engineering College of EngineeringShantou UniversityShantou 515063China Department of Civil Engineering Misr Higher Institute of Engineering and TechnologyMansouraEgypt Department of Civil Engineering Higher Future Institute of Engineering and TechnologyMansouraEgypt guangdong Engineering Center for Structure Safety and Health monitoring Shantou UniversityShantou 515063China Civil and Architectural Construction Department Faculty of Technology and EducationSuez UniversityIsmailiaEgypt Department of Civil and Environmental Engineering Collage of EngineeringUniversity of SharjahSharjah 27272UAE

This study presents a new systematic algorithm to optimize the durability of reinforced recycled aggregate *** proposed algorithm integrates machine learning with a new version of the firefly algorithm called chaotic based firefly algorithm(CFA)to evolve a rational and efficient predictive *** CFA optimizer is augmented with chaotic maps and Levy flight to improve the firefly performance in forecasting the chloride penetrability of strengthened recycled aggregate concrete(RAC).A comprehensive and credible database of distinctive chloride migration coefficient results is used to establish the developed algorithm.A dataset composite of nine effective parameters,including concrete components and fundamental characteristics of recycled aggregate(RA),is used as input to predict the migration coefficient of strengthened RAC as output,k-fold cross validation algorithm is utilized to validate the hybrid *** numerical benchmark analyses are applied to prove the superiority and applicability of the CFA algorithm in predicting chloride *** show that the developed CFA approach significantly outperforms the firefly algorithm on almost tested functions and demonstrates powerful *** addition,the proposed strategy can be an active tool to recognize the contradictions in the experimental results and can be especially beneficial for assessing the chloride resistance of RAC.

关键词： chloride penetrability recycled aggregate concrete machine learning concrete components durability

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Direct torque control of doubly fed induction motor using three-level NPC inverter

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Protection and Control of modern Power Systems 2019年第1期4卷 208-216页

作者： Najib el Ouanjli Aziz Derouich abdelaziz el ghzizal mohammed Taoussi Youness el mourabit Khalid mezioui Badre Bossoufi Laboratory of Production Engineering Energy and Sustainable DevelopmentHigher School of TechnologySidi Mohamed Ben Abdellah UniversityFezMorocco Laboratory of Systems Integration and Advanced Technologies Faculty of Sciences Dhar El MahrazSidi Mohamed Ben Abdellah UniversityFezMorocco Laboratory of electrical Engineering and maintenance ESTO School of TechnologyUniversity Mohammed IOujdaMorocco

This article presents the direct torque control (DTC) strategy for the doubly fed induction motor (DFIm) connected to two three-level voltage source inverters (3LVSIs) with neutral point clamped (NPC) structure. This control method allows to reduce the torque and flux ripples as well as to optimize the total harmonic distortion (THD) of motor currents. The use of 3LVSI increases the number of generated voltage, which allows improving the quality of its waveform and thus improves the DTC strategy. The system modeling and control are implemented in matlab/Simulink environment. The analysis of simulation results shows the better performances of this control, especially in terms of torque and flux behavior, compared to conventional DTC.

关键词： Direct torque control Doubly fed induction motor Three-level inverter Ripples Switching table

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