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Mafic and felsic magmatism in the Wadi Kalalat area, South Eastern Desert, Egypt: mineralogy, geochemistry and geodynamic evolution during the Neoproterozoic in the Nubian Shield

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Acta Geochimica 2024年第1期43卷 150-173页

作者： a.el A.Surour Ahmed A.Madani Mohamed a.el-Sobky Faculty of Science Galala UniversityNew Galala CitySuez 43511Egypt Department of Geology Faculty of ScienceCairo UniversityGiza 12613Egypt Egyptian Mineral Resources Authority P.O.Box 11517AbbasiyaCairoEgypt

In the south Eastern Desert of Egypt,two contrasting types of magmatism(mafic and felsic) are recorded in the Wadi Kalalat area,and form the Gabal el Motaghiarat and Gabal Batuga intrusions,*** two intrusions post-dates ophiolitic and arc associations represented by serpentinite and metagabbro-diorite,*** mafic intrusion has a basal ultramafic member represented by fresh peridotite,which is followed upward by olivine gabbro and anorthositic or *** mafic intrusion pertains to the Alaskan-type mafic-ultramafic intrusions in the Arabian-Nubian Shield(ANS)being of tholeiitic nature and emplaced in a typical arc *** the other hand,the Gabal Batuga intrusion comprises three varieties of fresh A-type granites of high K-calc alkaline nature,which is peraluminous and garnetbearing in parts.A narrow thermal aureole in the olivine gabbro of the mafic intrusion was developed due to the intrusion of the Batuga *** results in the development of a hornfelsic melagabbro variety in which the composition changed from tholeiitic to a calc-alkaline composition due to the addition of S_(i)O_(2),Al_(2)O_(3),alkalis,lithosphile elements(LILEs) such as Rb(70 ppm) and Y(28 ppm) from the felsic *** the thermal aureole,Rb amounts 2-8 ppm and Y lies in the range elieved that the Gabal Batuga felsic intrusion started to emplace during the waning stage of an arc system,with transition from the pre-collisional(i.e.,arc setting) to post-collisional and within plate *** from which the Gabal Batuga granites were fractionated is high-K calc-alkaline giving rise to a typical post-collisional A-type granite(A_(2)-subtype) indicating an origin from an underplating crustal ***,it is stressed here that the younger granites in the ANS are not exclusively post-collisional and within-plate but most likely they started to develop before closure of the arc *** possible source(s) of mafic magmas

关键词： Wadi Kalalat Gabal el Motaghairat mafic intrusion Gabal Batuga felsic intrusion Arc setting Post-collision Within-plate

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A comparative study of liquid and solid inner contact roxatidine acetate ion-selective electrode membranes

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Chinese Chemical Letters 2015年第6期26卷 714-720页

作者： Mohamed K.Abd el-Rahman Hala E.Zaazaa Samah S.Abbas Badr el-Zeany Zeinab a.el-Sherif Dalia a.el-Haddad Analytical Chemistry Department Faculty of PharmacyCairo University National Organization for Drug Control and Research

A comparative study was conducted using two designs of a roxatidine acetate （ROX）-selective electrode; a conventional liquid inner contact called electrode A and a graphite-coated solid contact called electrode 13. The fabrication of electrodes was based on roxatidine-tetraphenylborate （ROX-TPB） as an ion-association complex in a PVC matrix using different plasticizers. electrode A has a linear dynamic range of 2.2 ×10^-5 mol/L to 1.0 ×10^-2 mol/L, with a Nernstian slope of 54.7 mV/decade and a detection limit of 1.4 ×10^-6 mol/L. electrode B shows linearity over the concentration range of 1.0×10^-6 mol/L to 1.0×10^-2 tool/L, with a Nernstian slope of 51.2 mV/decade and a limit of detection of 1.1×10^7 mol/L which is remarkably improved as a result of diminishing ion fluxes in this solid contact, ion-selective electrode. The proposed sensors display useful analytical characteristics for the determination of ROX in bulk powder and its pharmaceutical formulation. The present electrodes show clear discrimination of ROX from several inorganic, organic ions, sugars, some common drug excipients and the degradation product （3-[3-（1-piperidinyl methyl） phenoxy] propyl amine） of ROX. Furthermore, the proposed electrodes were utilized for the determination of ROX in human plasma, where electrode B covers drug Cmax which indicated its applicability to pharmacokinetic, bioavailability and bioequivalent studies. The results obtained by the proposed electrodes were statistically analyzed and compared with those obtained by a reported HPLC method. No significant difference for either accuracy or precision was observed.

关键词： Comparative study Roxatidine acetate Liquid inner contact electrode Solid contact electrode Degradation product Plasma

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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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Reliability analysis of earth slopes using hybrid chaotic particle swarm optimization

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Journal of Central South University 2011年第5期18卷 1626-1637页

作者： M.Khajehzadeh M.R.Taha a.el-Shafie Civil and Structural Engineering Department University Kebangsaan MalaysiaBangi43600SelangorMalaysia

A numerical procedure for reliability analysis of earth slope based on advanced first-order second-moment method is presented,while soil properties and pore water pressure may be considered as random *** factor of safety and performance function is formulated utilizing a new approach of the Morgenstern and Price *** evaluate the minimum reliability index defined by Hasofer and Lind and corresponding critical probabilistic slip surface,a hybrid algorithm combining chaotic particle swarm optimization and harmony search algorithm called CPSOHS is *** comparison of the results of the presented method,standard particle swarm optimization,and selected other methods employed in previous studies demonstrates the superior successful functioning of the new method by evaluating lower values of reliability index and factor of ***,the presented procedure is applied for sensitivity analysis and the obtained results show the influence of soil strength parameters and probability distribution types of random variables on the reliability index of slopes.

关键词： reliability analysis stability assessment earth slopes particle swarm optimization harmony search

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Photopic negative response in diagnosis of glaucoma:an experimental study in glaucomatous rabbit model

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International Journal of Ophthalmology(English edition) 2015年第3期8卷 459-464页

作者： Amal a.el Gohary Laila Hassan M.elshazly Department of Ocular Physiology Research Institute of Ophthalmology Department of Ophthalmology Memorial Institute of Ophthalmology

AIM: To determine whether the photopic negative response(Ph NR) elicited by transient white flash on white background is characterizing for glaucoma model in ***: Glaucoma was induced in twelve rabbits by subconjunctival injection of 0.05 m L of betamethasone in right eyes(each 1 m L contain betamethasone dipropionate5 mg and betamethasone sodium phosphate 2 mg).The intraocular pressure(IOP), electroretinogram(ERG) and visual evoked potential(VEP) were measured successively prior and on the 3, 7d, two weeks and four weeks postglaucoma induction. After four weeks, the animals were sacrificed and the globes were histopathologically ***: The IOP increased significantly after one week(P =0.0001), then it gradually returned to the control level. In ERG examination, the means of a and b wave amplitude and latency were not affected *** NR amplitude decreased significantly within one week(P =0.0001), but its latency was not affected significantly(P =0.132). The means of VEP latency and amplitude were significantly affected after two weeks and four weeks of glaucoma induction(P =0.0001 and 0.02,respectively). The histopathologic examination of the globes showed reduced number of cells in the retinal ganglion cell layer with multiple vacuoles in the retinal nerve fibre *** was significant positive correlation between ganglion cell layer cells and Ph NR amplitude( r =0.8, P =0.002).CONCLUSION: The rise in IOP resulted in irreversible changes or incomplete recovery of VEP and Ph NR amplitude. Both Ph NR and VEP represented good additional tools in early diagnosis of glaucoma.

关键词： glaucoma electrophysiology photopic negative response rabbits

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Course Evaluation Based on Deep Learning and SSA Hyperparameters Optimization

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Computers, Materials & Continua 2022年第4期71卷 941-959页

作者： Alaa a.el-Demerdash Sherif E.Hussein John FW Zaki Department of Computer and Systems Faculty of EngineeringMansoura UniversityMansoura35516Egypt

Sentiment analysis attracts the attention of Egyptian Decisionmakers in the education *** offers a viable method to assess education quality services based on the students’feedback as well as that provides an understanding of their *** machine learning techniques offer automated strategies to process big data derived from social media and other digital channels,this research uses a dataset for tweets’sentiments to assess a few machine learning *** dataset preprocessing to remove symbols,necessary stemming and lemmatization is performed for features *** is followed by several machine learning techniques and a proposed Long Short-Term Memory(LSTM)classifier optimized by the Salp Swarm Algorithm(SSA)and measured the corresponding ***,the validity and accuracy of commonly used classifiers,such as Support Vector Machine,Logistic Regression Classifier,and Naive Bayes classifier,were ***,LSTM based on the SSA classification model was compared with Support Vector Machine(SVM),Logistic Regression(LR),and Naive Bayes(NB).Finally,as LSTM based SSA achieved the highest accuracy,it was applied to predict the sentiments of students’feedback and evaluate their association with the course outcome evaluations for education quality purposes.

关键词： Sentiment analysis course evaluation deep learning Bi-LSTM opinion mining students feedback natural language processing machine learning tweets analysis SSA

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Optimized system for combined production of electricity/green hydrogen for multiple energy pathways:a case study of Egypt

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Clean Energy 2024年第4期8卷 219-236页

作者： Reda Ragab Mohamed HamdiHafez a.el Salmawy Mohamed A.Ismail Mechanical Power Engineering Department Zagazig UniversityZagazig 44519Egypt Mechanical Engineering Department College of EngineeringKing Faisal UniversityAl-Ahsa 31982Saudi Arabia

By optimal sizing of a wind/photovoltaic hybrid renewable-energy(RE)system,trimming the surplus capacity to reduce the fluctuations in the electricity supplied to the grid,and using it to produce green hydrogen through electrolysis,a stable output with maximum possible capacity factor(CF)is generated to maintain the electricity grid ***,the trimmed energy is used in a secondary conversion path that minimizes the weighted average cost of the energy generated from the entire *** surplus power-to-gas conversion allows the use of green hydrogen to produce electricity,methanol,or ammonia subject to the resource availability,site characteristics,and financial *** on robust site selection criteria,the best performance is obtained at two sites:Ras Ghareb and Minya,achieving the lowest energy cost with some variance in their *** the Ras Ghareb site,the optimally sized RE plant provided the grid with a quasi-steady capacity of 423 MW with a CF of 80.04%and was capable of injecting 2965.8648 GWh throughout the year with the lowest cost of 2.4355¢/kWh.A surplus of 3.9%of the total energy produced from the plant was directed to produce 1922-ton H_(2)/year,achieving the lowest cost of hydrogen production of$1.9745/kg H_(2).For the other selected site,Minya,the clipped energy is used to produce 3330.47-ton H_(2)/year with an optimized lowest cost of$3.5268/kg H_(2).The difference in hydrogen costs was attributed to the number of full operating hours of the electrolyser in both *** cost is mainly affected by the electricity price and the electrolyser *** both tending to decrease,future forecasts show hydrogen cost reductions.

关键词： hybrid renewable-energy system(HRES) green hydrogen electrolysis power-to-gas methanol ammonia

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Ion-acoustic waves in plasma of warm ions and isothermal electrons using time-fractional KdV equation

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Chinese Physics B 2011年第4期20卷 149-155页

作者： Sayed a.el-Wakil Essam M.Abulwafa Emad K.el-Shewy Abeer A.Mahmoud Theoretical Physics Research Group Physics DepartmentFaculty of ScienceMansoura University

The ion-acoustic solitary wave in collisionless unmagnetized plasma consisting of warm ions-fluid and isothermal electrons is studied using the time fractional KdV equation. The reductive perturbation method has been employed to derive the Korteweg-de Vries equation for small but finite amplitude ion-acoustic wave in warm plasma. The Lagrangian of the time fractional KdV equation is used in a similar form to the Lagrangian of the regular KdV equation with fractional derivative for the time differentiation. The variation of the functional of this Lagrangian leads to the Euler-Lagrange equation that gives the time fractional KdV equation. The variational-iteration method is used to solve the derived time fractional KdV equation. The calculations of the solution are carried out for different values of the time fractional order. These calculations show that the time fractional can be used to modulate the electrostatic potential wave instead of adding a higher order dissipation term to the KdV equation. The results of the present investigation may be applicable to some plasma environments, such as the ionosphere plasma.

关键词： ion-acoustic waves Euler-Lagrange equation Riemann-Liouvulle fractional derivative fractional KdV equation variational-iteration method

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Towards creation of national cerebral palsy registries in Arab countries:what is missing?

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World Journal of Pediatrics 2022年第3期18卷 222-224页

作者： Sahar M.A.Hassanein Tamer a.el-Sobky Division of Pediatric Neurology Department of PediatricsFaculty of MedicineAin Shams UniversityCairoEgypt Division of Pediatric Orthopedics Department of Orthopedic SurgeryFaculty of MedicineAin Shams UniversityCairoEgypt

Cerebral palsy(CP)is a global,complex and lifelong health issue with a relatively high disease burden in low-resource *** benefits of a national disease registry in general and a national CP registry in particular are twofold,na.ely the public health and the clinical disease-related benefits.A national CP quality registry has the potential to inform health planning and spending at national,regional and continental *** turn,this can help allocate and manage the relevant material and human resources in a more predictable and efficient manner.

关键词： benefits palsy creation

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Micro-fabrication of ceramics:Additive manufacturing and conventional technologies

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Journal of Advanced Ceramics 2021年第1期10卷 1-27页

作者： Hany HASSANIN Khamis ESSA Amr elSHAER Mohamed IMBABY Heba H.el-MONGY Tamer a.el-SAYED School of Engineering Canterbury Christ Church UniversityCanterburyCT11QUUK University of Birmingham EdgbastonB152TTUK Kingston University London Penrhyn RoadKingston Upon ThamesSurreyKT12EEUK Department of Mechanical Design Faculty of EngineeringMatariaHelwan UniversityP.O.Box.11718CairoEgypt Jubail University College Mechanical EngineeringKingdom of Saudi Arabia Center for Applied Dynamics Research(CADR) School of EngineeringUniversity of AberdeenAberdeenAB243UEUK

Ceramic materials are increasingly used in micro-electro-mechanical systems(MEMS)as they offer many advantages such as high-temperature resistance,high wear resistance,low density,and favourable mechanical and chemical properties at elevated ***,with the emerging of additive manufacturing,the use of ceramics for functional and structural MEMS raises new opportunities and *** paper provides an extensive review of the manufacturing processes used for ceramic-based MEMS,including additive and conventional manufacturing *** review covers the micro-fabrication techniques of ceramics with the focus on their operating principles,main features,and processed *** that need to be addressed in applying additive technologies in MEMS include ceramic printing on wafers,post-processing at the micro-level,resolution,and quality *** paper also sheds light on the new possibilities of ceramic additive micro-fabrication and their potential applications,which indicates a promising future.

关键词： micro-electro-mechanical system(MEMS) micro-fabrication ceramics micro parts additive manufacturing

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