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Petrology and Geochemistry of Some Ophiolitic metaperidotites from the Eastern Desert of Egypt:Insights into Geodynamic Evolution and metasomatic Processes

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Acta Geologica Sinica(English Edition) 2021年第4期95卷 1139-1157页

作者： abdel-aal m.abdel-KARIm mokhles K.AZER Shaimaa A.El-SHAFEI Geology Department Faculty of ScienceZagazig UniversityZagazig 44519Egypt Geological Sciences Department National Research Centre12622-DokkiCairoEgypt

Ophiolitic peridotites exposed in the Eastern Desert(ED)of Egypt record multiple stages of evolution,including different degrees of partial melting and melt extraction,serpentinization,carbonatization and *** present study deals with metaperidotites at two selected localities in the central and southern ED,nam.ly Wadi El-Nabáand Wadi Ghadir,*** represent residual mantle sections of a Neoproterozoic dismembered ophiolite that tectonically emplaced over a volcano-sedimentary succession that represents island–arc *** studied metaperidotites are serpentinized,with the development of talc-carbonate and quartz-carbonate rocks,especially along shear and fault *** relics of primary minerals(olivine,orthopyroxene and Cr-spinel)are preserved in a few sam.les of partiallyserpentinized *** of the Cr-spinel crystals have fresh cores followed by outer zones of ferritchromite and Crmagnetite,which indicates that melt extraction from the mantle protolith took place under oxidizing *** protoliths of the studied metaperidotites were dominated by harzburgites,which is supported by the abundance of mesh and bastite textures in addition to some evidence from mineral and whole-rock chemical *** high Cr#(0.62–0.69;Av.0.66)and low TiO_(2)(ls,the higher Fo(89–92;Av.91)and NiO(0.24–0.54 wt%,Av.0.40)contents of the primary olivine relics,together with the high mg#(0.91–0.93;Av.91)and low CaO,Al2 O3 and TiO_(2)of the orthopyroxene relics,are all comparable with depleted to highly depleted forearc harzburgite from a suprasubduction zone *** investigated peridotites have suffered subsequent phases of metasomatism,from oceanfloor hydrothermal alteration(serpentinization)to magmatic hydrothermal *** enrichment of the studied sam.les in light rare earth elements(lREEs)relative to the heavy ones(HREEs)is attributed to most probably be due to the contamination

关键词： ophiolitic metaperidotites partial melting melt extraction geodynamic evolution Eastern Desert Egypt

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Geochemistry of island arc assemblage in the Eastern Desert of Egypt and the role of Pan-African magmatism in crustal growth of the Arabian–Nubian Shield:A review

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Acta Geochimica 2024年第3期43卷 588-622页

作者： abdel-aal mabdel-Karim mohamed mHamdy Adel A.Surour Geology Department Faculty of ScienceZagazig UniversityZagazig 44519Egypt Geology Department Faculty of ScienceTanta UniversityTanta 31527Egypt Department of Geological Sciences Faculty of ScienceNew Galala City 43511Egypt Geology Department Faculty of ScienceCairo UniversityGiza 12613Egypt

Neoproterozoic island arc assemblage of the Arabian–Nubian Shield(ANS)in the Eastern Desert(ED)of Egypt comprises juvenile suites of metavolcanics(mV),large amounts of meta-sedimentary rocks(mS),and voluminous metagabbros-diorites(mGD)and syn-tectonic intrusions of older granitoids(OG).We report here the updates of these four rock units in terms of classification,distribution,chemical characteristics,geodynamic evolution,metamorphism,and *** addition,we discuss these integrated data to elucidate a reasonable and reliable model for crustal evolution in the *** main features of these rock units indicate their relation to each other and the geodynamic environment dominated by early immature oceanic island arcs to primitive continental *** information of the island arc metavolcanic and plutonic rocks(gabbros,diorites,tonalites,and granodiorites)furnish evidence of the genetic *** include proximity and a coeval nature in the field;all protolith magmas are subalkaline in nature following calc-alkaline series with minor tholeiitic affinities;common geochemical signature of the arc rocks and subduction-related magmatism;their similar enrichment in lREEs;and similar major element compositions with mafic melts derived from metasomatized mantle *** volcano-sedimentary and the OG rocks underwent multiphase deformation events whereas the mGD complexes deformed *** on the magmatic,sedimentological,and metamorphic evolutions constrained by geochronological data as well as the progressive evolutionary trend from extensional to compressional regimes,a possible gradual decrease in the subducted slab dip angle is the most infl uential in any geodynamic model for arc assemblage in the ED of Egypt.

关键词： Island arc assemblage magmatism Crustal growth Neoproterozoic Arabian–Nubian Shield Eastern Desert Egypt

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Nanoscale electropolishing of high-purity nickel with an ionic liquid

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International Journal of minerals,metallurgy and materials 2019年第5期26卷 649-656页

作者： Jon Derek loftis Tarek m.abdel-Fattah Applied Research Center at Thomas Jefferson National Accelerator Facility and Department of molecular Biology and Chemistry at Christopher Newport University Department of Physical Sciences Virginia Institute of Marine Science College of William and Mary Faculty of Sciences Alexandria University

High purity(>99.9% composition) nickel metal specimens were used in electropolishing treatments with an acid-free ionic liquid electrolyte prepared from quaternary ammonium salts as a green polishing solution. Voltammetry and chronoamperometry tests were conducted to determine the optimum conditions for electrochemical polishing. Atomic force microscopy(AFm) revealed nanoscale effectiveness of each polishing treatment. Atomic force microscopy provided an overall observation of the material interface between the treated and unpolished regions. Surface morphology comparisons summarized electrochemical polishing efficiency by providing root-mean-square roughness averages before and after electrochemical polishing to reveal a mirror finish six times smoother than the same nickel metal surface prior to electropolishing. This transition manifested in a marked change in root-mean-squared roughness from 112.58 nm to 18.64 nm and producing a smooth mirror finish. Finally, the mechanism of the ionic liquid during electropolishing revealed decomposition of choline in the form of a transient choline radical by acceptance of an electron from the nickel-working electrode to decompose to trimethylamine and ethanol.

关键词： electrochemical polishing ionic liquid Ni 2EG:1VB4

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Synthesis of new 1,2,4-oxadiazolidin-5-ylthiophenes and thienopyrimidine derivatives by aza-Wittig reaction using a thienyl carbodiimide

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Chinese Chemical letters 2012年第4期23卷 411-414页

作者： Afaf m.abdel Hameed Chemistry Department Faculty of ScienceMinia University

Azidation of aminothiophene derivative 1 afforded the corresponding azido derivative *** latter reacted with triphenylphosphine to afford iminophosphorane derivatives *** 3 with phenylisocyanate gave the highly reactive carbodiimide intermediate 4,which was reacted with different nitrones to afford new l,2,4-oxadiazolidin-5-ylidene-aminothiophenes 5a-c. Treatment of 4 with absolute EtOH at room temperature gave methyleneamino-5-（methylthio）thiophene 7,（methylthio）-3-（3- phenylureidothiophene）-2-carboxylate 8 or thienopyrimidine 9 and 10 at refluxing *** reaction of carbodiimide intermediate 4 with different secondary amines gave the new thienopyrimidines 11a-c.

关键词： Carbodiimide Cycloaddition 1 2 4-Oxadiazolidin-5-ylideneaminothiophene derivatives Thienopynmidine Aza-Wittig reaction

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Crosstalk between androgen signaling and the chemokine receptor CXCR4:a novel strategy to promote myelin regeneration

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Neural Regeneration Research 2025年第9期20卷 2581-2582页

作者： marianne Bardy-lagarde Narimène Asbelaoui abdel mouman Ghoumari UmR1195 “Diseases and Hormones of the Nervous System”Inserm and University Paris-SaclayKremlin-BicêtreFrance

multiple sclerosis(mS)is the most common chronic disease of the central nervous system(CNS)in young adults and represents the first cause of severe handicap,originally non-traumatic(Oh et al.,2018).mS is chara cterized by the infiltration of auto reactive lymphocytes specific to myelin through the blood-brain barrier,which results in the appearance of inflammatory demyelinating lesions caused by the death of the central nervous system myelinating cells,oligodendrocytes(Oh et al.,2018).There is a prevalence sexual with a ratio of three times more affected women than men.

关键词： myelin CXCR4

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Can lanthanum doping enhance catalytic performance of silver in direct propylene epoxidation over NamoAg/SiO_2?

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Journal of Rare Earths 2019年第5期37卷 500-507页

作者： Hany m.abdel Dayem Shar S.Al-Shihry Salah A.Hassan Chemistry Department Faculty of Science Ain Shams University Chemistry Department College of Science King Faisal University

In the attempt to reduce surface free energy of silica to improve interaction of silica with silver, silica was doped by different amounts of low surface energy lanthanum, la_2O_3, through impregnation. The doped and undoped silica were used as supports for preparation of Na/Ag/mo/la_2O_3-SiO_2 catalysts. Catalytic performances of the catalysts were evaluated in direct epoxidation of propylene(DPO) using molecular oxygen under atmospheric pressure and without adding hydrogen. Adding 5 wt%la to the Na/Ag/mo/SiO_2 catalyst improves both the catalysts electivity in DPO and its stability over 20h of *** characterization results show that la_2O_3 species interact strongly with silver particles on the silica surface which result in significant improvement in the dispersion profile of silver and marked decrease in the size of silver nanoparticles(AgNPs). The estimated mean diameter of AgNPs is ca. 4.0 nm in Na/Ag/mo/5 wt%la_2O_3-SiO_2, which is smaller than that(53.9 nm) found in Na/Ag/SiO_2. The presence of subnanometer AgNPs on Ag/la_2O_3-SiO_2 prior addition of moO_3 and NaCl to the sam.le can enhance the mutual electronic synergism between Ag, moO_3 and Na for selective production of propylene oxide.

关键词： Direct epoxidation Propylene Gas phase Silver Subnanometer lanthanum

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Development of new potentiometric sensors for the determination of proguanil hydrochloride in serum and urine

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Chinese Chemical letters 2016年第6期27卷 857-863页

作者： Fatehy m.abdel-Haleem mohamed Saad mohamed S.Rizk Chemistry Department Faculty of Science Cairo University

Potentiometric electrodes were developed for the rapid determination of proguanil hydrochloride in pure sam.les, pharmaceutical preparations and spiked serum and urine sam.les using PVC membrane,screen printed（SPE）, coated wired（CWE）, carbon paste（CPE） and modified carbon paste（mCPE）electrodes based on the ion-exchanger of proguanil with phosphotungestic acid（Pr-PT） as a chemical modifier. The prepared electrodes showed Nernestian slopes of 59.7, 58.1, 58.5, 58.5 and 57.0 for the PVC,SPE, CWE, CPE and mCPE for the proguanil ions in a wide concentration range of 1.0 ＊ 10^-5–1.0 ＊ 10^-2mol l^-1 at 25°C with detection limits of 7.94 ＊ 10^-6, 1.0 ＊ 10^-5, 1.0 ＊ 10^-6, 7.07 ＊ 10^-6 and 2.5 ＊ 10^-6 mol l^-1, respectively. The prepared electrodes exhibited high proguanil selectivity in relation to several inorganic ions and sugars and they could be successfully utilized for its determination in pure solutions, pharmaceutical preparations and serum and urine sam.les using the direct potentiometry and standard addition methods with very good recovery values.

关键词： Proguanil hydrochloride PVC membrane electrode Carbon paste electrode Screen printed electrode mWCNTs Coated wire electrode

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Skew Information for a Single Cooper Pair Box Interacting with a Single Cavity Field

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Communications in Theoretical Physics 2013年第6期59卷 769-772页

作者： N.metwally A.Al-mannai m.abdel-Aty mathematics Department College of Science University of Bahrain mathematics Department Faculty of Science Aswan University of Aswan Scientific Publishing Center University of Bahrain mathematics Department Faculty of Science Sohag University of Sohag

The dynamics of the skew information (SI) is investigated for a single Cooper Pair Box (CPB) interacting with a single cavity field. By suitably choosing the system parameters and precisely controlling the dynamics, novel connection is found between the SI and entanglement generation. It is shown that SI can be increased and reach its maximum value either by increasing the number of photons inside the cavity or considering the far off-resonant *** number of oscillations of SI is increased by decreasing this ratio between the Josephson junction capacity and the gate capacity. This leads to significant improvement of the travelling time between the maximum and minimum values.

关键词： entanglement skew information Cooper Pair Box

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Information under lorentz Transformation

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Communications in Theoretical Physics 2014年第1期61卷 32-36页

作者： N.metwally H.Eleuch m.abdel-Aty Department of mathematics Faculty of ScienceAswan University mathematics Department College of ScienceBahrain University DIRO Universitde MontralH3T 1J4MontralCanada Scientific Publishing Center Bahrain University Department of mathematics Faculty of ScienceSohag University

In the context of quantum information,we investigate extensively some important classes of a general form of a two-qubit system under lorentz *** is shown lorentz transformation causes a decay of entanglement and consequently information *** the other hand,it generates entangled states between systems prepared initially in a separable *** partial entangled states are more robust under lorentz transformation than maximally entangled *** the rate of information lose is larger for maximum entangled states compared with that for partially entangled states.

关键词： entanglement lorentz 03.65.Yz 03.67.-a 42.50.-p transformation two-qubit system

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Performance,emissions and exergy analyses of adding CNTs to various biodiesel feedstocks

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Propulsion and Power Research 2022年第4期11卷 511-526页

作者： m.S.Gad mostafa m.abdel Aziz Hatem Kayed mechanical Engineering Department Faculty of EngineeringFayoum UniversityEgypt mechanical Engineering Department Institute of Aviation Engineering and TechnologyGizaEgypt mechanical Power Engineering Department Faculty of EngineeringCairo University12613Egypt

Extraction of biodiesel from waste cooking oil,jatropha,and corn oils is done by *** and biodiesel were blended at 20%volume ratio to make methyl *** doses of 25,50,and 100 mg/l,carbon nanotubes(CNTs)was mixed with biodiesel *** objective of the present research is to examine experimentally a diesel engine performance,combustion characteristics,exergy and emissions analyses with inclusion of nano additive to various methyl ester *** ester blend is enriched with CNTs as JB20C100,WB20C100 and CB20C100 where the improvements in thermal efficiency are raised about biodiesel mixture by 9%,13%and 15%,*** of 100 ppm of CNTs to biodiesel blends achieves the greatest reductions in CO(14%,22%and 30%),HC(16%,20%and 25%),and smoke emissions(15%,19%and 23%)for JB20C100,WB20C100 and CB20C100,*** comparing with B20,blending 100 ppm CNTs with JB20,CB20,and WB20 obtained the highest increases in cylinder pressure of 3%,5%,and 10%,as well as the highest increases in heat release of 4%,7%,and 11%,*** downside of CNTs addition achieves a rise in NOx emissions by 10%,17%,and 22%for JB20C100,WB20C100,and CB20C100,*** efficiency increases by 8%,19%,and 24%for B20T100,B20A100,and B20C100,*** index improvements achieve 1.5%,5%and 6.5%,for B20T100,B20A100,and B20C100,***20 with CNTs of 100 ppm is highly recommended for improving engine performance,combustion,and exergy characteristics with considerable emissions reduction.

关键词： Biodiesel Carbon nanotubes(CNTs) Engine performance Exergy Combustion characteristics Emissions

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