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Petrology, geochemistry, radioactivity, and M–W type rare earth element tetrads of el Sela altered granites, south eastern desert,Egypt

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Acta Geochimica 2019年第1期38卷 95-119页

作者： A.M.el Mezayen M.A.Heikal M.G.el-Feky H.A.Shahin I.K.Abu Zeid S.R.Lasheen Geology Department Faculty of Science Al Azhar University Nuclear Material Authority

The southern part of the Eastern Desert of Egypt—about 30 km southwest of Abu-Ramad city—is mainly covered by ophiolitic rocks(Sul Hamed), island arc assemblage, younger granites(muscovite granites of Qash Amer and two mica granites of el Sela), and various acidic and basic dikes. Field, petrological, and geochemical studies indicate that the el Sela shear zone has been subject to hydrothermal and supergene alteration such as kaolinization, albitization, sericitization, and hematitization. It is invaded by quartz ENE–WSW veins associated with hydrothermal alteration accompanied by radioactive mineralization. The investigated younger granitic rocks had very low contents of compatible elements, such as Cr, Ni,and Co; and high contents of incompatible elements, such as Zr, and large ion lithophiles, such as Sr, especially in the el Sela shear zone. Major oxide and trace element analyses revealed calc-alkaline affinity and peraluminous *** highly differentiated granitic rocks' lower Zr/Hf and higher y/Ho than the normal ratio are consistent with hydrothermal alteration. Most samples had rare earth element(REE)-patterns with an M-type tetrad effect in the first and fourth segments and a W-type tetrad in the third segment. The average ∑REE in the studied granites was lower than the world granite average; the ratio of light to heavy REEs greater. The main radioactive, uranium-bearing, and uraniferous Fe and Mn minerals are uranothorite,autunite, uranophane and autunite as compounds, kasolite,columbite, xenotime, uranophane-bearing zircon and jarosite, silver-bearing pyrite, hematite, and autunite-bearing pyrolusite.

关键词： Geochemistry REE-tetrad effect Radioactive minerals Radiometric measurements Qash Amer el Sela

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Eye Detection-Based Deep Belief Neural Networks and Speeded-Up Robust Feature Algorithm

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Computer Systems Science & Engineering 2023年第6期45卷 3195-3213页

作者： Zahraa Tarek Samaa M.Shohieb Abdelghafar M.elhady el-Sayed M.el-kenawy Mahmoud y.Shams Faculty of Computers and Information Mansoura UniversityMansoura35516Egypt Deanship of Scientific Research Umm Al-Qura UniversityMakkah21955KSA Delta Higher Institute of Engineering and Technology Mansoura35111Egypt Faculty of Artificial Intelligence Kafrelsheikh UniversityKafrelsheikh33511Egypt

The ability to detect and localize the human eye is critical for use in security applications and human identification and verification *** is because eye recognition algorithms have multiple challenges,such as multi-pose variations,ocular parts,and ***,the modern security applica-tions fail to detect facial expressions from eye *** this paper,a Speeded-Up Roust Feature(SURF)Algorithm was utilized to localize the face images of the enrolled *** highlighted on eye and pupil parts to be detected based on SURF,Hough Circle Transform(HCT),and Local Binary Pattern(LBP).Afterward,Deep Belief Neural Networks(DBNN)were used to classify the input features results from the SURF *** further determined the correctly and wrongly classified subjects using a confusion matrix with two class labels to classify people whose eye images are correctly *** apply Stochastic Gradient Descent(SGD)optimizer to address the overfitting problem,and the hyper-parameters arefine-tuned based on the applied *** accuracy of the proposed system is determined based on SURF,LBP,and DBNN classifier achieved 95.54%for the ORL dataset,94.07%for the BioID,and 96.20%for the CASIA-V5 *** proposed approach is more reliable and more advanced when compared with state-of-the-art algorithms.

关键词： Eye localization classification DBNN detection feature extraction LBP feature extraction SURF

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Effect of diluents on the extraction of praseodymium and samarium by Cyanex 923 from acidic nitrate medium

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Journal of Rare Earths 2010年第2期28卷 215-220页

作者： yA el-Nadi Hot Laboratories Centre Atomic Energy Authority(Egypt)

The solvent extraction of Pr(Ⅲ) and Sm(Ⅲ) with trialkyl phosphine oxide(Cyanex 923) in chloroform,carbon tetrachloride,n-octane,cyclohexane,1,2-dichloroethane,benzene,toluene,xylene and nitrobenzene from acidic nitrate medium was *** the basis of slope analysis data,the composition of the extracted species was determined as(M(NO3)3?2Cy923),Cy923 refers to Cyanex *** values of the equilibrium constants and the separation factors were *** effect of the diluents on the metal extracti...

关键词： extraction diluents praseodymium samarium Cyanex 923 rare earths

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Effect of different metal sulfate precursors on structural and catalytic performance of zirconia in dehydration of methanol to dimethyl ether

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燃料化学学报 2018年第1期46卷 67-74页

作者： Abd el-Aziz A.Said Mohamed Abd el-Aal Chemistry Department Faculty of ScienceAssiut University71516 AssiutEgypt

ZrO_2 was treated with 10% SO_4^(2-) from different metal sulfate precursors for methanol dehydration to dimethyl *** the samples exhibited tetragonal phase and no diffraction peaks corresponding to metal sulfates or metal oxides were *** FT-IR results revealed that there were different interactions between sulfate and ZrO_2,and this had a great effect on the surface area of the *** catalytic activity was measured over the catalysts in the temperature range of 100-300 ℃.The results revealed that sulfated zirconia with CuSO_4·5 H_2O and Al_2(SO_4)_3·16 H_2O showed the best catalytic *** maximum yield of DME ≈87% was obtained over CuSZ at a reaction temperature of 275 ℃.Moreover,the catalytic activity of the catalysts was correlated well with their surface acidity that measured by dehydration of isopropanol.

关键词： MSO 4/ZrO2 甲醇脱水 DME

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Effect of Tempcore Processing on Mitigating Problems of Tramp elements in Low C Steel Produced from Recycled Material

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Journal of Iron and Steel Research International 2015年第7期22卷 582-589页

作者： Ahmed RAMADAN A.y.SHASH I.S.el-MAHALLAWI D.SENK Taha MATTAR Quality Department Faculty of Engineering Cairo University Institute of Ferrous Metallurgy RWTH-Aachen University Central Metallurgical Research and Development Institute

The effect of tramp elements in the steel was intensively studied. It was found that the solubility of tramp elements decreased as the temperature decreased under normal cooling conditions. The tramp elements （Cu, Pb, and Sn） diffused toward the grain boundaries, and intermetallic compounds or rich phases which have low melting points were formed, causing reduction in ductility and failure during the bending test. Rebars with Cu content which were left to air cooling after the last step showed drop in elongation, up to 32 %. On contrast, the samples with high per- centage of tramp elements （Cu, Pb, and Sn） in the billet, which were rolled and subjected to Tempcore process, did not show drop in elongation or failure in bending test （especially for rebar with diameter less than 32 mm）; however, copper must be less than 0.35 mass% to prevent the precipitation of Cu-rich zones of critical size in 32 mm. When quench- ing was applied, the tramp elements remained in the interstitial supersaturated solid solution positions inside the grains and would not have the chance to diffuse and form precipitates, hindering the copper precipitates from reac- hing the critical size necessary for impairing the properties. This would hinder the occurrence of the harmful effect of the tramp elements on the elongation or the hot shortness after rolling.

关键词： recycled steel hot shortness crack susceptibility Tempcore process tramp element residual melt

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pH-indicative Films Based on Chitosan–PVA/Sepiolite and Anthocyanin from Red Cabbage: Application in Milk Packaging

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Journal of Bionic Engineering 2022年第3期19卷 837-851页

作者： Marya Raji Laila el Foujji Mohamed el Mehdi Mekhzoum Mounir el Achaby Hamid Essabir Rachid Bouhfid Abou el kacem Qaiss Moroccan Foundation for Advanced Science Innovation and ResearchComposites and Nanocomposites CenterRabat Design CenterRue Mohamed El JazouliMadinat El IrfaneRabat10100Morocco Faculty of Science Laboratoire de Chimie Organique Et HétérocycliqueUniversity Mohammed V in RabatRabat10100Morocco Materials Science and Nano-Engineering Department Mohammed VI Polytechnic UniversityLot 660–Hay Moulay RachidBen Guerir43150Morocco Mechanic Materialsand Composites(MMC)Laboratory of Energy EngineeringMaterials and SystemsNational School of Applied Sciences of AgadirIbn Zohr UniversityAgadir80000Morocco

Biobased smart packaging is been the most interesting research *** this study,pH-sensitive films based on anthocyanin molecules from red cabbage and sepiolite mineral nano-clay as functional additives were *** films were fabricated by casting method of blend polymer Chitosan/Poly(Vinyl Alcohol)at two fillers loading(5wt.%and 10wt.%).The structural,morphological,thermal,optical,hygroscopic,and mechanical properties as well as the pH sensitivity of films were *** thermal properties confirm that the amount of the anthocyanin in sepiolite was around 6.4%.The tensile strength and the young’s modulus of produced composites at 10wt.%sepiolite–anthocyanin content was increased to 8.90 MPa and 163 MPa,*** maximum water absorption that the films may absorb was 12.3%.pH sensitivity analysis showed that the Smart films change the color by changing the pH level,from pink at pH lower than 6 to yellow at pH higher than ***,the developed pH-sensitive films show band gaps in visible light that make them useful for monitoring milk spoilage.

关键词： Smart packaging Anthocyanin Red cabbage pH-sensitive and milk spoilage

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Thermal explosion of a reactive gas mixture at constant pressure for non-uniform and uniform temperature systems

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Defence Technology（防务技术） 2022年第10期18卷 1842-1851页

作者： Saad A.el-Sayed Mechanical Power Engineering Dept.Zagazig University ZagazigAlshrkiaEgypt

In this study,the approximate and exact solutions for the stationary-state of the solids model with neglecting reactant consumption for both non-uniform and uniform temperature systems were applied on gas ignition under a constant pressure *** criticality conditions for a slab,an infinite cylinder,and a sphere are determined and discussed using dimensionless temperatures under constant ambient and surface temperatures for a non-uniform temperature *** solution for a Semenov model with convection heat loss was also *** solution of the Semenov problem for constant volume or density as a solid and constant pressure were *** critical parameterδis calculated and compared with those of Frank-Kamenetskii solution *** validation of the calculated ignition temperatures with other exact solution and experimental results were *** relation between critical parameters form Semenov and *** solution was introduced.

关键词： Thermal explosion Approximate solution Critical conditions Distributed and uniform temperature systems

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Regional constrained control problem for a class of semilinear distributed systems

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Control Theory and Technology 2018年第3期16卷 221-231页

作者： el Hassan ZERRIK Nihale el BOUKHARI MACS team Faculty of Sciences Moulay Ismail University Meknes Morocco

The aim of this paper is to investigate a regional constrained optimal control problem for a class of semi[inear distributed systems, which are linear in the control but nonlinear in the state. For a quadratic cost functional and a closed convex set of admissible controls, the existence of an optimal control is proven, and then this is characterized for three cases of constraints. A useful algorithm is developed, and the approach is illustrated through simulations for a heat equation.

关键词： Semilinear distributed systems regional optimal control constraints heat equation

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Energy Efficient Scheduler of Aperiodic Jobs for Real-time Embedded Systems

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International Journal of Automation and computing 2020年第5期17卷 733-743页

作者： Hussein el Ghor el-Hadi MAggoune University Institute of Technology Lebanese UniversityLebanon Sensor Networks and Cellular Systems(SNCS)Research Center UTSaudi Arabia electrical Engineering Department University of Tabuk Sensor Networks and Cellular Systems(SNCS)Research Center 71491 TabukSaudi Arabia

Energy consumption has become a key metric for evaluating how good an embedded system is,alongside more performance metrics like respecting operation deadlines and speed of *** improvement is no longer the only metric by which optimality is *** fact,energy efficiency is becoming a preferred choice with a fundamental objective to optimize the system's *** this work,we propose an optimal energy efficient scheduling algorithm for aperiodic real-time jobs to reduce CPU energy ***,we apply the concept of real-time process scheduling to a dynamic voltage and frequency scaling(DVFS)*** address a variant of earliest deadline first(EDF)scheduling algorithm called energy saving-dynamic voltage and frequency scaling(ES-DVFS)algorithm that is suited to unpredictable future energy production and irregular job *** prove that ES-DVFS cannot attain a total value greater than C/ˆSα,whereˆS is the minimum speed of any job and C is the available energy *** also investigate the implications of having in advance,information about the largest job size and the minimum speed used for the competitive factor of *** show that such advance knowledge makes possible the design of semi-on-line algorithm,ES-DVFS∗∗,that achieved a constant competitive factor of 0.5 which is proved as an optimal competitive *** experimental study demonstrates that substantial energy savings and highest percentage of feasible job sets can be obtained through our solution that combines EDF and DVFS optimally under the given aperiodic jobs and energy models.

关键词： Real-time systems energy efficiency aperiodic jobs scheduling dynamic voltage scaling low-power systems embedded systems

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Overview, prevention and management of chemotherapy extravasation

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World Journal of Clinical Oncology 2016年第1期7卷 87-97页

作者： Firas y Kreidieh Hiba A Moukadem Nagi S el Saghir Division of Hematology-Oncology Department of Internal Medicine American University of Beirut Medical Center Breast Center of Excellence NK Basile Cancer Institute American University of Beirut Medical Center

Chemotherapy extravasation remains an accidental complication of chemotherapy administration and may result in serious damage to patients. We review in this article the clinical aspects of chemotherapy extravasation and latest advances in definitions, classification, pre-vention, management and guidelines. We review the grading of extravasation and tissue damage according to various chemotherapeutic drugs and present an update on treatment and new antidotes including dexrazoxane for anthracyclines extravasation. We highlight the importance of education and training of the oncology team for prevention and prompt pharmacological and non-pharmacological management and stress the availability of new antidotes like dexrazoxane wherever anthracyclines are being infused.

关键词： Chemotherapy Extravasation Vesicant Tissue damage Dimethyl sulfoxide Dexrazoxane Antidote Hyaluronidase

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