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Geology and geochemistry of the granitic rocks and associated dykes,East Gabal Nuqra,South Eastern Desert,Egypt

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Chinese Journal Of Geochemistry 2012年第4期31卷 376-389页

作者： ibrahim h.ibrahim Mostafa E.Darwish Nuclear Material Authority 530 P.O.El MaadiCairoEgypt

A crescent-shape granitic stock and associated dykes is located to the East Gabal Nuqra at the extreme western part of Wadi Natash,South Eastern Desert,*** examined granites are classified as alkali-feldspar granites and mainly consist of quartz,potash feldspars,plagioclases,and ***,zircon,apatite and allanite are accessories representing the source of Y,U,Th and REEs in these *** granites are characterized by high K2O,Na2O and Zn contents and Rb/Sr ***,they are highly enriched in high field strength elements(hFSE),especially Zr(1529×10-6),Nb(100×10-6),hf(91×10-6) and Y(624×10-6) and light rare-earth elements(LREE,141×10-6) concentrations and strongly depleted in Ca,Mg,Sr and Eu *** features suggest that they are similar to A-type granites(type-2).The rhyolite dykes and granites have similar geochemical characteristics whereas the chondrite-normalized REE patterns show a LREE enriched feature with strong negative Eu-anomaly,whereas the REE pattern of trachydacites show slightly fractionated pattern with no *** is suggested that the trachydacites were generated by small degree of partial-melting deep-seated basic *** liquid,when subjected to fractional crystallization involving separation of plagioclases as residue,generated the alkali-feldspar *** further fractional crystallization gave rise to the alkali *** igneous rock suite originated from metaluminous to alkaline trachytic magma,and was developed in a within-plate tectonic *** extension caused by NW-SE right-lateral shear in area led to the emplacement of the alkali-feldspar *** later extrusion of the alkali rhyolite and trachydacite dykes was due to cauldron subsidence.

关键词：碱长花岗岩地球化学特征堤坝沙漠埃及轻稀土元素碱性流纹岩元素富集特征

ELECTRORhEOLOGY AND CREEP-RECOVERY BEhAVIOR OF CONDUCTING POLYThIOPhENE/POLY(OXYMEThYLENE)-BLEND SUSPENSIONS

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Chinese Journal of Polymer Science 2012年第1期30卷 16-25页

作者： Ozlem Erol h.ibrahim Unal Bekir Sari Smart Materials Research Lab Chemistry Department Gazi UniversityAnkaraTurkey

Electrorheological properties and creep-recovery behavior of polythiophene/polyoxymethylene-blend having PT（50%）/POM（50%） composition were *** size,conductivity and dielectric values were measured to be 24.77μm,3.85×10^（-5） S·m^（-1） and 26.75,*** ratio was measured to be 64%at the end of 16 *** effects of dispersed particle volume fraction,external electric field strength,shear rate,frequency and temperature on ER properties and storage modulus of PT/POM-blend/silicone oil（SO） suspensions were *** were observed in the electric field viscosities of the suspensions and thus they were classified as a smart *** thinning non-Newtonian viscoelastic behavior was determined for PT/POM-blend/SO ***,time-dependent deformation was examined by creep-recovery tests and recoverable viscoelastic deformation established.

关键词： Conducting polythiophene/poly(oxymethylene) Blends Electrorheogical fluids Creep-recovery behavior

The efficiency of direct integration methods in elastic contact-impact problems

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Acta Mechanica Sinica 2005年第4期21卷 395-401页

作者： ibrahim h.Guzelbey Ahmet Erklig Bahattin Kanber University of Gaziantep Mechanical Engineering DepartmentGaziantep-Turkey

A comparison of direct integration methods is madeand their efficiency is investigated for impact ***-mark,Wilson-θ,Central Difference and houbolt Methodsare used as direct integration *** analysisincludes that of elastic and large deformation based uponupdated Lagrangian including buckling *** resultsshow that the direct integration methods give differentresults in different contact-impact cases.

关键词： Elastic impact,Direct integration methods,Finite strain Contact

Synthesis of some new fused coumarin derivatives

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Chinese Journal of Chemistry 2000年第4期18卷 590-595页

作者： EL-DEEN ibrahim Mohey ibrahim h.K. MAhMOUD F.F. Faculty of Education Suez Canal University Port-Said EgyptFaculty of Science Suez Canal University Ismailia EgyptFaculty of Science (for Girls) Al-Azhar University Nasr City Egypt

2-hydrazino-4-hydroxy-5h-[1]-benzopyrano-[4,3-d]-pyrimidin-5-one (3) was prepared via condensation of 2 with hydrazine hydrate. Treatment of 3 with methylene chloride, ethyl chloroformate, ethyl chloroacetate and benzaldehyde yielded the corresponding 2 - ( substituted ) hydrazino - 4 -hydro-xy-5h-[1]-benzopyrano-[4,3-d]-pyrimidin-5-one (4, 5, 6, and 10), followed by cyclization of 4, 5 and 6 with dimethyl formamide and fused sodium acetate under reflux, while compound 10 was cyclized with bromine and sodium acetate in acetic acid. Compound 3 reacted with β-(toloyl) acrylic acid, ethyl α-cyano-p-methoxycinnamate, diethyl malonate and acetyl chloride affording the corresponding 2-(substituted) hydrazino-4-hydroxy-5h-[1]-benzopyrano-[4,3-d]-pyrimidin-5-one (12, 13, 14, 15 and 16).

关键词： Synthesis fused coumarin derivatives cyclization

Structural, M?ssbauer spectroscopy, magnetic properties, and thermal measurements of Y(3-x)Dy_x Fe_5O_(12)

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Chinese Physics B 2018年第10期27卷 558-564页

作者： Mahdi Lataifeh Qassem I Mohaidat Sami h Mahmood ibrahim Bsoul Mufeed Awawdeh ibrahim Abu-Aljarayesh Mu'ath Altheeba Physics Department Yarmouk University Irbid 21163 Jordan Physics Department The University of Jordan Amman 11942 Jordan Physics Department AI al-Bayt University Mafraq 13040 Jordan

Yttrium iron garnet powder samples（Y3-xDyxFe5O12）, where part of yttrium ions are substituted by dysprosium ions with different concentrations are prepared by the solid state reaction method. The properties of the prepared samples are examined by different methods such as x-ray diffraction（XRD）, Mssbauer spectroscopy, macroscopic magnetization measurements, and thermal measurements. The XRD measurements show that all the samples reveal the presence of a single garnet phase with a BCC structure. Room temperature Mssbauer spectra indicate that iron ions occupy three magnetic sites, i.e., two octahedral sites and one tetrahedral site. The saturation magnetization and the initial magnetic susceptibility decrease with the increase of Dy^3＋ substitution. The Curie temperature obtained from the thermal measurements seems to be independent of Dy^3＋ substitution.

关键词： Mossbauer spectroscopy magnetic properties x-ray diffraction differential scanning calorimetry

Novel synthesis of stabilized Bi_(1-x-y)Gd_(x)Dy_(y)O_(1.5) solid electrolytes with enhanced conductivity for intermediate temperature solid oxide fuel cells(SOFCs)

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Journal of Rare Earths 2024年第10期42卷 1903-1911页

作者： Ahmed h.ibrahim Yehia M.Abbas h.A.Ayoub Marwa h.Ali Mustafa Aldoori Materials Science Laboratory Physics DepartmentFaculty of ScienceSuez Canal University41522IsmailiaEgypt Ministry of higher Education and Scientific Research Aliraqia University10011BaghdadIraq

herein,we report the synthesis of a Dy-Gd co-doped cubic phase-stabilized Bi_(2)O_(3) solid electrolyte system via solid-state processing under atmospheric *** with Dy^(3+) and Gd^(3+) has been observed to significantly enhance the densification process during sintering for stabilization purposes,thereby improving the electrical properties of δ-Bi_(2)O_(3)-type *** synthesized ceramics were characterized using X-ray diffraction(XRD),field emission scanning electron microscopy-energy dispersive X-ray spectroscopy(FESEM-EDX),thermal gravimetry/differential thermal analysis(TG/DTA),and the four-point probe technique(4PPT).XRD analysis reveals that the samples Bi_(1-x-y)Gd_(x)Dy_(y)O_(1.5)(y=0.05/x=0.05,0.10,0,15,and 0.20,and x=0.05/y=0.10,0.15,and 0.20) exhibit a stable face-centered cubic δ-phase and a mixed-phase crystallographic *** XRD analysis of the stabilized δ-phase suggests that the prepared oxides show a face-centered cubic(FCC) structure with a space group of *** micrographs reveal that the composition Bi_(0.90)Gd_(0.05)Dy_(0.05)O_(1.5) has no significant ***,an evident increase in the pore formation is observed as the amount of Gd_(2)O_(3) increases until it reaches 20%.This finding suggests that dense pellets are formed during the sintering process at 900-1000℃.The DTA analyses were performed to verify the phase stability,which agrees with the XRD *** electrochemical performance of the synthesized Dy-Gd co-doped Bi_(2)O_(3)solid electrolyte system was evaluated and analyzed in detail by using the electrochemical impedance spectroscopy(EIS) technique,Based on EIS and conductivity measurements,Bi_(0.75)Gd_(0.20)Dy_(0.05)O_(1.5) exhibits the lowest activation energy of 0.519 eV and the highest conductivity value of 0.398 S/cm at 627℃compared to the other samples;this composition can be used as a solid electrolyte for intermediatetemperature solid oxide fuel cells(SOFCs).

关键词： Solid oxide fuel cells(SOFCs) Rare earths Solid-state processing Rietveld Fast Fourier transform(FFT) Electrochemical impedance spectroscopy(EIS)

NEW POLY(METhACRYLATE)S CONTAINING OXIME ESTERS MOIETIES BASED ON CYCLOhEXANON AND CYCLOPENTANON

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Chinese Journal of Polymer Science 2008年第4期26卷 443-454页

作者： ibrahim Erol Afyon Kocatepe Universty Faculty of Science and Arts Department of ChemistryAfyonkarahisarTurkey

The synthesis of two new methacrylates such as 2-[(cyclohexylideneamino)oxy]-2-oxoethyl methylacrylate (ChOEMA)and 2-[(cyclopentylideneamino)oxy]-2-oxoethyl methylacrylate(CPOEMA)are *** monomers produced from the reaction of corresponding cyclohexanone O-(2-chloroacetyl)oxime and cyclopentanone O-(2- chloroacetyl)oxime with sodium methacrylate was polymerized in 1,4-dioxane solution at 65℃using AIBN as an initiator. The monomers and their polymers were characterized by IR,~1h- and ^(13)C-NMR spec...

关键词： Methacrylate Oxime esters Activation energy Thermal decompositionv Biological activitiy

Wear Behaviour of Plasma Paste Boronized of AISI 8620 Steel with Borax and B_2O_3 Paste Mixtures

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Journal of Materials Science & Technology 2013年第7期29卷 662-668页

作者： ibrahim Gunes Department of Metallurgical and Materials Engineering Faculty of TechnologyAfyon Kocatepe UniversityAfyonkarahisar 03200Turkey

In the present study, AlSl 8620 steel was plasma paste boronized （PPB） by using paste mixtures with different borax and B2O3 percentages. The PPB process was carried out in a DC plasma system at 973, 1023 and 1073 K for 5 h in a gas mixture with 70% h2-30% Ar under a constant pressure of 103 Pa （10 mbar）. The thickness of boride layers ranged from 15.9 to 53.6 tim depending on the temperature and process time. The hardness of the borides formed on the surface of the steel substrate and unborided steel substrate were 1648-1924 hV0.05 and 226 hV0.05, respectively. X-ray diffraction analysis of the boride layers on the surface of the samples were obtained for FeB and Fe2B phases. The wear tests on the steel were performed by using a ball-on-disc test device at room temperature with applied load of 10 N and with a shear velocity of 0.2 m/s. Wear test results showed that the highest value of wear rate was observed in the unborided sample while the lowest wear rate was observed in the PPB samples with 30% borax ＋ 70% B4C paste at 1073 K for 5 h.

关键词： Coating Borax B2O3 Wear Coefficient of friction

Supplementary optical solitonic expressions for Gerdjikov–Ivanov equations with three Kudryashov-based methods

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Communications in Theoretical Physics 2024年第12期76卷 3-14页

作者： F A Althrwi A A Alshaery h O Bakodah Rahmatullah ibrahim Nuruddeen Department of Mathematics and Statistics Faculty of Science University of Jeddah Department of Mathematics Faculty of Physical Sciences Federal University Dutse

The present manuscript uses three Kudryashov-based methods to analytically inspect the class of Gerdjikov–Ivanov equations, which comprises the standard Gerdjikov–Ivanov equation and the perturbed Gerdjikov–Ivanov equation. Various optical solitonic solutions have been ***, as the reported solitonic structures happened to be exponential functions, diverse true solitonic solutions can easily be resorted to upon suitably fixing the involving parameters,including mainly the bright and singular solitons. Lastly, the study graphically examined some of the constructed structures, which were then found to portray some interesting known shapes in the theory of solitary waves and nonlinear Schr?dinger equations. Additionally, the Kudryashovindex d has been noted to play a significant role in the propagation of complex waves in the nonlinear media described by Gerdjikov–Ivanov equations.

关键词： Gerdjikov-Ivanov equation Kudryashov-based methods perturbed Gerdjikov-Ivanov equation Schrödinger equations solitonic solutions