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Geochemistry and spectrometric prospection of younger granites and granitic pegmatites bearing uranium mineralization at *** El Rakeb area, Central Eastern Desert, Egypt

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Acta Geochimica 2021年第4期40卷 575-601页

作者： Gehad m.Saleh bahaa m.Emad ibrahim b.Abdel Kader Nuclear materials Authority El MaadiP.O.Box 530CairoEgypt

The present study deals with the detailed field geology,mineralogy,geochemistry,and spectrometric prospection of rare metals and radioactive minerals associated with granitic pegmatites in the Gabal Um LassafAbu Dob-Um Atelia-Kadabora-Kab El Rakeb area(LDAKK),which are situated in the central Eastern Desert of *** study area is composed of granodiorites and *** latter is dissected by granitic pegmatites with a discriminatory distribution of economically important mineralization(rare-metals and U-Th minerals).The granitic pegmatites display a zoning structure composed of feldspar-rich zones enveloping pockets of mica(mostly muscovite) and all zoning internal quartz ***,the monzogranite and granitic pegmatites are composed of potash-feldspar,albite,and quartz with a small amount of biotite and *** mineralogical investigation of the highly radioactive zones in the granitic pegmatite shows enrichment in kasolite,uranothorite,thorite,xenotime,columbite,zircon,bismuth,and ***,the granitic pegmatites are enriched with high field strength elements(HFSE;Zr,Nb,Th,and U) and ion lithophilic elements(LILE;Rb,and Pb) and depleted in ba,Sr,and *** are strongly peralkaline to metalumainous except for two samples,which are *** are formed by partial melting of metagreywackes at *** studied granitic pegmatites could belong to the NYF family(Niobium-Yttrium-Fluorine family) according to the geochemistry of the trace *** studied granitic pegmatites show deep negative Eu anomaly and display a strong m-type tetrad effect of rare earth *** field spectroscopy measurements showed the localization of the radiometric anomalous associated with the granitic pegmatites,which are intruded in the granitic host *** eU and eTh contents reached up to 316 and 1367 ppm,*** and thorium occurrences in the investigated granitic pegmatites are related to magmatic(syngenetic)ori

关键词： Geochemistry Gabal Um Lassaf-Abu Dob-Um Atelia-Kadabora-Kab El Rakeb area(LDAKK) Uranium REE Egypt

A Novel 1×2 Thermo-Optic multimode Interference Switch Structure based on Photodefinable benzocyclobutene （bCb 4024-40） Polymer on Silica

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Chinese Physics Letters 2006年第10期23卷 2796-2798页

作者： m.H.ibrahim mee-Koy Chin N.m.Kassim A.b.mohammad Photonics Research Croup Universiti Teknologi Malaysia Johor Malaysia Photonics Research Center Nanyang Technological University Singapore

A novel 1× 2 multimode interference photonics switch structure based on thermal controlling effect is proposed. A ridge waveguide of photosensitive polymer, benzocyclobutene （bCb 4024-40） on silica clad is used as a design structure. A temperature changes as a result of electrode heating are analysed by employing a two-dimensional finite difference thermal model considering both conduction and convection mechanisms. The switching characteristics due to changes in effective index are analysed by the two-dimensional finite difference beam propagation method with transparent boundary condition. The proposed structure works well with low crosstalk level of -28 db and low switching power relatively to the structural upper cladding thickness.

关键词： WAVE-GUIDES

Approximate analytical solutions and mean energies of stationary Schrodinger equation for general molecular potential

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Chinese Physics b 2021年第7期30卷 116-131页

作者： Eyube E S Rawen b O ibrahim N Department of Physics School of Physical SciencesModibbo Adama University of TechnologyP M B 2076 YolaAdamawa StateNigeria Directorate of basic and Remedial Studies Abubakar Tafawa Balewa University(ATBU)P M B 750001BauchiBauchi StateNigeria Department of Physics Faculty of ScienceP M B 1069MaiduguriBorno StateNigeria

The Schrodinger equation is solved with general molecular potential via the improved quantization *** for bound state energy eigenvalues,radial eigenfunctions,mean kinetic energy,and potential energy are obtained in compact *** modeling the centrifugal term of the effective potential,a Pekeris-like approximation scheme is ***,we use the Hellmann–Feynman theorem to derive the relation for expectation *** state energy eigenvalues,wave functions and meanenergies of Woods–Saxon potential,morse potential,mobius squared and Tietz–Hua oscillators are deduced from the general molecular *** addition,we use our equations to compute the bound state energy eigenvalues and expectation values for four diatomic molecules viz.H_(2),CO,HF,and O_(2).Results obtained are in perfect agreement with the data available from the literature for the potentials and *** also show that as the vibrational quantum number increases,the mean kinetic energy for the system in a Tietz–Hua potential increases slowly to a threshold value and then *** in a morse potential,the mean kinetic energy increases linearly with vibrational quantum number increasing.

关键词： general molecular potential Schrodinger equation improved quantization rule

Structural, elastic and electronic properties for m_2 XC (m=Ti and Cr, X=Ga and Al) phases from ab initio calculations

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Acta metallurgica Sinica(English Letters) 2011年第4期24卷 255-270页

作者： b. Ghebouli m.A. Ghebouli m. Fatmi N. bouarissa m. benkerri I.A. ibrahim Laboratory of Study of Surfaces and Interfaces of Solids materials Department of Physics Faculty of Science University of Setif Department of Physics University Center Research Unit on Emerging materials Ferhat Abbas University of Setif Department of Physics Faculty of Sciences King Khalid University Central metallurgical Research and Development Institute P.O. box: 87 Helwan 11424 Cairo Egypt

The first-principles study of the structural, elastic and electronic properties of the m2XC phases depending on the type of m transition metal （m are Ti and Cr） and on X （X are Ga and A1） was reported. The calculations are performed using the pseudo-potential plane-wave approach in both the local density and generalized gradient approximations. The elastic constants are calculated using the static finite strain technique. Features such as structural and elastic parameters, Debye tem- perature, sound velocities and their pressure dependence have been investigated. In agreement with experimental and previous theoretical findings, it is found that the compressibility along a and c axis depends on the valence electron concentration （VEC）. Correlations revealing the governing role of the X and m elements on the machinability indices of the material have been examined. The electronic properties have been discussed in terms of chemical bonding showing that bonding is due to md-Cp and md-Xp hybridizations. m-C bonds are stiffer than m-X ones and A1-Ti （Cr-C） bonds are stiffer than those corresponding to Ti-C （A1-Cr）. It is shown that the stiffness of the m-X and m-C bonds increases with increasing the number of VEC.

关键词： m2XC phases ab initio Pressure effect band structures

The possible source of uranium mineralization in felsic volcanic rocks,Eastern Desert,Egypt of the Arabian-Nubian Shield:Constraints from whole-rock geochemistry and spectrometric prospection

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Acta Geochimica 2021年第5期40卷 819-845页

作者： Gehad.m.Saleh bahaa.m.Emad ibrahim.b.Abdel Kader Rania.m.Sakr Nuclear materials Authority El MaadiP.O.Box 530CairoEgypt

The present work deals with the detailed geology,mineralogy,geochemistry,and spectrometric prospection of the felsic volcanic rocks at the Eastern Desert,Egypt of the Arabian-Nubian *** volcanic rocks are an essential source for rare earth elements(REEs)and uranium occurrences in this *** are compositionally uniform with tholeiitic to calc-alkaline affinities,peraluminous and belong to the series of rhyolite with high-K *** exhibit more enrichment in high field strength elements(HFSE,***,Ta,Nd,Th,and U)and large-ion lithophile elements(LILE,*** and Rb)compared to the country rocks of the studied area,with REE ranging from 188.20 to 442.70 ppm and strong depletion in Ti,Sr,P with deep negative Eu *** felsic volcanic rocks were mostly generated from the partial melting of quartz-amphibolite facies accreted during the *** oddities of Zr-U-Th for the felsic volcanic rocks determine the involvement of crustal *** volcanic rocks are found in A-type suites of magma and represent highly fractionated rocks derived from rhyolitic magma,with insignificant interaction with continental crust in the low-pressure environment and during fractional *** volcanic rocks have higher values of radioactivity in which eU range from 0.5 to 121 ppm and eTh from 1.0 to 415.10 *** high values of eU and eTh can be ascribed to the mineralization of uranium and the presence of accessory minerals of radiogenic nature such as uranophane,uranothorite,zircon,and *** is considered as the mineral with most enriched uranium contents in the studied felsic volcanic rocks in which(UO2=87.30 wt%).Also,they are enriched with REE-bearing accessory minerals comprising allanite,titanite,and *** geological investigations of the felsic volcanic rocks in the studied areas are inappropriate to clear the feasible economic potentialities of rare earth elements and U occurrences;itemized and invaluable

关键词： Felsic volcanic rocks Geochemistry REE Uranium mineralization Egypt Arabian-Nubian Shield

Recovery of NH4^＋ by corn cob produced biochars and its potential application as soil conditioner

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Frontiers of Environmental Science & Engineering 2014年第6期8卷 825-834页

作者： Yang ZHANG Zifu LI ibrahim b mAHmOOD School of Civil & Environmental Engineering University of Science and Technology Beijing Beijing 100083 China

NH4^＋ ion, a main pollutant in aquatic systems, not only causes eutrophication in rivers and lakes but also contributes to fish toxicity. In this study, an eco-friendly biosorbent was prepared from the pyrolysis of corn cob, a low-cost agricultural residue. The biochars produced by pyrolysis of corn cob at 400℃ and 600℃ were characterized and investigated as adsorbents for NH4＋ -N from an aqueous solution. The biochars were characterized through elemental analysis, brunauer-Emmett-Teller-N2 surface area analysis, scanning electron microscopy, and Fourier transform infrared spectroscopy. batch experiments were conducted to investigate the NH4＋ adsorption process of the corn cob biochars. The Freundlich isotherm model fitted the adsorption process better than the Langmuir and Dubinin-Radushkevich isotherm models. moreover, the adsorption process was well described by a pseudo-second-order kinetic model. Results of thermodynamic analysis suggested that adsorption was a nonspontaneous exothermic process. biochars produced at 400℃ had higher adsorption capacity than those produced at 600℃ because of the presence of polar functional groups with higher acidity. The exhausted biochar can be potentially used as soil conditioner, which can provide 6.37 kg NH4＋-N-t^-1 （N fertilizer per ton of biochar）.

关键词： corn cob biochar NH+ adsorption isotherm model kinetic model

High Order block method for Third Order ODEs

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Computers, materials & Continua 2021年第4期67卷 1253-1267页

作者： A.I.Asnor S.A.m.Yatim Z.b.ibrahim N.Zainuddin School of Distance Education Universiti Sains MalaysiaUSM Penang11800Malaysia Department of mathematics Faculty of ScienceUniversiti Putra MalaysiaSerdangSelangor Darul Ehsan43400Malaysia Department of Fundamental and Applied Sciences Universiti Teknologi PETRONASSeri IskandarPerak Darul Ridzuan32610Malaysia

many initial value problems are difficult to be solved using ordinary,explicit step-by-step methods because most of these problems are considered *** implicit methods,however,are capable of solving stiff ordinary differential equations(ODEs)usually found in most applied *** study aims to develop a new numerical method,namely the high order variable step variable order block backward differentiation formula(VSVOHObbDF)for the main purpose of approximating the solutions of third order *** computational work of the VSVO-HObbDF method was carried out using the strategy of varying the step size and order in a single *** order of the proposed method was then discussed in *** advancement of this strategy is intended to enhance the efficiency of the proposed method to approximate solutions *** order to confirm the efficiency of the VSVO-HObbDF method over the two ODE solvers in mATLAb,particularly ode15s and ode23s,a numerical experiment was conducted on a set of stiff *** numerical results prove that for this particular set of problem,the use of the proposed method is more efficient than the comparable ***-HObbDF method is thus recommended as a reliable alternative solver for the third order ODEs.

关键词： block method stiff ODEs third order variable step variable order

bibliometric mapping of solid lipid nanoparticles research(2012–2022)using VOSviewer

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medicine in Novel Technology and Devices 2023年第1期17卷 132-140页

作者： Siddig ibrahim Abdelwahab manal mohamed Elhassan taha Sivakumar S.moni Abdulrahman A.Alsayegh medical Research Centre Jazan UniversityJazanP.O.Box 45142Saudi Arabia Department of Pharmaceutics College of PharmacyJazan UniversityJazan45142Saudi Arabia Department of Clinical Nutrition College of Applied Medical SciencesJazan UniversityJazan45142Saudi Arabia

Nanotechnology is a rapidly expanding discipline,and solid lipid nanoparticles(SLN)are at the forefront of this *** offer various possible clinical and pharmaceutical research applications and numerous other fields.A quantitative review technique called bibliometric analysis uses statistics,data mining,and mathematics to find emerging trends in a particular academic *** is currently more widely utilized and is employed in many academic *** a result,the current study looked through Scopus-indexed research documents on SLNs from 2012 to 2022 to assess the growth and expansion of this body of knowledge and predict its course in the *** VOSviewer package and Scopus Analytics were used to conduct the bibliometric *** offers two distinct viewing modes:network and overlay visualization.A total of 3768 journal articles(n=3709)and conference papers(n=59)were *** number of research documents published by 12,367 authors was steadily increasing *** therapy,development and detection methods,bioavailability,and controlled release have been important research ***,E.b.,of the University of Porto in Portugal,is considered the most prolific and frequently cited *** University(India)is the top-publishing *** is the leading country in the number of publications and research *** International Journal of Pharmaceutics is the top *** current results keep pace with global scientific efforts in nanotechnology and successfully integrate them into the pharmaceutical industry.

关键词： Solid lipid nanoparticles bibliometric analysis Scientific mapping Knowledge structure Performance analysis

bianchi type I in f(T) gravitational theories

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Chinese Physics b 2016年第5期25卷 58-64页

作者： m I Wanas G G L Nashed O A ibrahim Astronomy Department Faculty of Science Cairo University Cairo Egypt Centre for Theoretical Physics The British University in Egypt El-Sherouk City Egypt mathematics Department Faculty of Science Ain Shams University Cairo Egypt Egyptian Relativity Group (ERG) Giza Egypt

A tetrad field that is homogeneous and anisotropic which contains two unknown functions A（t） and b（t） of cosmic time is applied to the field equations of f（T）, where T is the torsion scalar, T = T~μ_（νρ）S_μ^（νρ）. We calculate the equation of continuity and rewrite it as a product of two brackets, the first is a function of f（T） and the second is a function of the two unknowns A（t） and b（t）. We use two different relations between the two unknown functions A（t） and b（t） in the second bracket to solve it. both of these relations give constant scalar torsion and solutions coincide with the de Sitter one. So,another assumption related to the contents of the matter fields is postulated. This assumption enables us to drive a solution with a non-constant value of the scalar torsion and a form of f（T） which represents ΛCDm.

关键词： f(T) gravitational theory bianchi type I special solutions