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mineralogy,m-type tetrad effect and radioactivity of altered granites at the *** Garadi shear zone,central Eastern Desert,Egypt

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Chinese Journal Of Geochemistry 2011年第2期30卷 153-164页

作者： el Nahas h.A. el Feky m.G. mira h. Nuclear materials Authority P.O. Box 530 Cairo Egypt

The G. Abu Garadi area is covered mainly by metasediments, alkali feldspar granites and stream sediments. The alkali feldspar granite is traversed by a major strike-slip fault trending in an N-S direction as well as two subordinate sets of faults trending NW to WNW for the first one and NE for the second one. These faults represent the shear zones affected by magmatic (syngenetic) as well as hydrothermal (epigenetic) activities causing alteration of the granitic rocks. The most common alteration features are albitization, greisenization and koalinitization. The mass balance calculations of the studied altered samples show enrichments in Zr, Y, Ni, U, Th and Ga and depletions in Zn, Sr, Nb, Ba, Pb, Cu and V. Only the greisenized samples exhibit a significant enrichment in Nb, ∑REE budget and pronounced lanthanide tetrad effect (m-type), especially TE1,4, while weakly expressed tetrad effects are for the other albitized and koalinitized samples. mineralogically, the common accessory minerals in the altered samples include samarskite-(Y), betafite, uranothorite, zircon, fluorite and cassiterite. The greisenized granites contain high eU and eTh than the other altered types, where they are characterized by an assemblage of the radioactive minerals; samarskite-(Y), betafite, uranothorite in addition to zircon. The inter-element relationships between U and Th and also their ratios illustrate that the radioelement distribution in these granites is mainly governed by magmatic processes, in addition to post-magmatic ones. The distribution of chemical elements and the fractionation of some isovalents within the shear zone are largely controlled by the newly formed mineral phases. With respect to uranium mobilization, uranium migrated from the host alkali feldspar granites of G. Abu Garadi, while the shear zones acted as traps for the migrated uranium. moreover, U migrated in the shear zone during greisenization and albitization, and migrated out during koalinitization.

关键词： m 类型四个效果改变的花岗石 G。Abu Garadi 砍地区中央东方沙漠埃及

Coexistence and fluctuations phenomena with Davidson-like potentials in quadrupoleoctupole deformed nuclei

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Communications in Theoretical Physics 2021年第3期73卷 105-118页

作者： m m hammad W h mansour E m el-maghraby h A motaweh Ayman A Aly Faculty of Science Mathematics DepartmentDamanhour UniversityEgypt Faculty of Science Physics DepartmentDamanhour UniversityEgypt

The energy spectra of three types of two-dimensional potentials(we will call them‘Davidson-like potentials’(DLPs)),characterized by four minima separated by barriers,are *** predictions for spectra and wave functions are obtained by using the nine-point finite-difference *** these potentials,with the existence of a single configuration,a transition of spectra,as a function of barrier height,is covered from tunneling splitting modes to fluctuations phenomena,with equal peaks wave functions,crossing to the spectra of purely anharmonic oscillator potentials(AOPs).A different type of phase transition occurs when two(or more)configurations *** the change of the parameters,a transition of spectra is covered from coexistence phenomena of two distinct quantum tunneling modes to fluctuations phenomena,with unequal peaks wave functions,crossing to the spectra of purely *** DLPs,a particular application of the coherent quadropole-octupole model to describe energy bands with alternating parity of the nuclei^(100)mo,^(146,148)Nd,^(148,150)Sm,^(220)Ra,^(220,222)Rn,and^(220,222)Th is *** global parametrization of the model for the selected nuclei is achieved.

关键词： quantum phase transitions fluctuations phenomena coherent quadrupole-octupole motion model coexistence phenomena

A new approach for modelling the damped helmholtz oscillator:applications to plasma physics and electronic circuits

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Communications in Theoretical Physics 2021年第3期73卷 119-130页

作者： S A el-Tantawy Alvaro h Salas m R Alharthi Department of Physics Faculty of SciencePort Said UniversityPort Said 42521Egypt Research Center for Physics(RCP) Department of PhysicsFaculty of Science and ArtsAl-MikhwahAl-Baha UniversitySaudi Arabia Department of mathematics Universidad National de ColombiaUniversidad National de Colombia-Nubia Campus Derpartment of Mathematics and Statistics FIZMAKO Research GroupColombia Department of mathematics and Statistics College of ScienceTaif UniversityPO Box 11099Taif 21944Saudi Arabia

In this paper,a new approach is devoted to find novel analytical and approximate solutions to the damped quadratic nonlinear helmholtz equation(hE)in terms of the Weiersrtrass elliptic *** exact solution for undamped hE(integrable case)and approximate/semi-analytical solution to the damped hE(non-integrable case)are given for any arbitrary initial *** a special case,the necessary and sufficient condition for the integrability of the damped hE using an elementary approach is *** general,a new ansatz is suggested to find a semi-analytical solution to the non-integrable case in the form of Weierstrass elliptic *** addition,the relation between the Weierstrass and Jacobian elliptic functions solutions to the integrable case will be derived in ***,we will make a comparison between the semi-analytical solution and the approximate numerical solutions via using Runge-Kutta fourth-order method,finite difference method,and homotopy perturbation method for the first-two ***,the maximum distance errors between the approximate/semi-analytical solution and the approximate numerical solutions will be *** real applications,the obtained solutions will be devoted to describe the characteristics behavior of the oscillations in RLC series circuits and in various plasma models such as electronegative complex plasma model.

关键词： damped and undamped helmholtz equation Korteweg-de Vries type equation plasma oscillations nonlinear RLC circuits Weierstrass ellliptic function periodical solution

helically symmetric equilibria for some ideal and resistive mhD plasmas with incompressible flows

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Applied mathematics(A Journal of Chinese Universities) 2023年第2期38卷 192-209页

作者： S.m.moawad O.h.el-Kalaawy h.m.Shaker mathematics and Computer Science Department Faculty of ScienceBeni-Suef UniversityBeni-SuefEgypt Future high Institute of Engineering in Fyoum Ministry of High EducationFyoumEgypt

In this paper, the problem of finding exact solutions to the magnetohydrodynamic(mhD) equations in the presence of incompressible mass flows with helical symmetry is considered. For ideal flows, a similarity reduction method is used to obtain exact solutions for several mhD flows with nonlinear variable mach number. For resistive flows parallel to a magnetic field, the governing equilibrium equation is derived. The mhD equilibrium state of a helically symmetric incompressible flow is governed by a second-order elliptic partial differential equation(PDE) for the helical magnetic flux function. Exact solutions for the latter equation are obtained. Also, the equilibrium equations of a gravitating plasma with incompressible flow are derived.

关键词： magnetohydrodynamics helical symmetry resistivity incompressible ows exact equilibria

Numerical Study of Greenhouse Nocturnal heat Losses

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Journal of Thermal Science 2011年第4期20卷 377-384页

作者： F.Berroug E.K.Lakhal m.el Omari m.Faraji h.el Qarnia Laboratoire d'Automatique de l'Environnement et Procédés de Transfert UniversitéCadi AyyadFacultédes Sciences Semlalia-Département de PhysiqueMarrakech-MarocAffiliéau CNRSTURAC 28 Laboratoire de Physique des materiaux MicroelectroniqueAutomatique et TechniqueDepartement de PhysiquesFaculte des Sciences Ain ChockUniversite Hassan IICasablanca-Maroc

In this study we quantify and analyze different components of nocturnal losses from a heated greenhouse with the presence of vegetation for typical winter weather conditions in marrakesh-morocco,using a non linear model,based on the greenhouse heat and mass *** was found that 12% of the total input heat was dissipate as a sensible and latent leakage losses,66% was lost by convective exchange through air-inner *** gain of energy at the inner-cover is dissipated at the outer-cover by radiation(66%)and convection(34%).This results point toward some practical measures to reduce heat losses:increasing air tightness,using covering materials with low-emissivity in the long wave band or putting up an external thermal curtain should provide significant energy savings.

关键词： Greenhouse energy balance heat losses numerical analysis.

Radiolabeling of lacosamide using highly purified rhenium-188 as a prospective brain theranostic agent

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Nuclear Science and Techniques 2020年第10期31卷 105-114页

作者： h.A.el-Sabagh m.I.Aydia A.m.Amin K.m.el-Azony Labeled Compound Department Radioisotopes Production DivisionHot Laboratory CenterAtomic Energy AuthorityP.O.Box 13759 CairoEgypt Radioactive Isotopes and Generators Department Radioisotopes Production DivisionHot Laboratory CenterAtomic Energy AuthorityP.O.Box 13759 CairoEgypt

Rhenium-188 is prospectively effective for both diagnosis and radiotherapy as it appropriately emits gamma rays and beta ***(LCm)is a newly approved antiepileptic medication for focal drug-resistant ***-188 was separated with high elution yield and high purity using the new 188W/188Re generator based on the ZrSiW gel matrix.188Re-LCm was prepared with high radiochemical yield and high *** of 188Re-LCm in normal Swiss albino mice was investigated to determine its utility as a potential brain therapy *** 188W/188Re generator was used to obtain 188Re based on the ZrSi188W gel matrix,and the chemical,radiochemical,and radionuclidic purity of the obtained 188Re was determined using inductively coupled plasma optical emission spectrometry(ICP-AES),a paper chromatography technique,and high-purity germanium(hPGe)detection,respectively,to assess its validity for LCm *** factors,such as the ph,reaction time,and LCm quantity,were therefore studied in order to improve the yield and purity of 188Re-LCm,as determined by various chromatographic techniques such as electrophoresis,thin layer chromatography(TLC),and highpressure liquid chromatography(hPLC).188Re was obtained with a high elution yield(75±3%)and a low 188W breakthrough(0.001±0.0001%).The maximum radiochemical yield of 188Re-LCm(87.5±1.8%)was obtained using 50 ll LCm(4 mm),250 ll stannous chloride(4.4 mm)at ph 4,100 ll 188Re(37 mBq),within 30 min,at room temperature(25±3C),as determined by TLC,electrophoresis,and hPLC *** analysis showed that 188Re-LCm was primarily localized in the brain(5.1%)with a long residence time(240 min).

关键词： Lacosamide 188Re 188W/188Re generator Radiolabeling

Nonequivalent Similarity Reductions and Exact Solutions for Coupled Burgers-Type Equations

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Communications in Theoretical Physics 2012年第1期57卷 1-4页

作者： m.h.m.moussa R.A.K.Omar Rehab m.el-Shiekh h.R.el-melegy Department of mathematics Faculty of EducationAin Shams UniversityHeliopolisCairoEgypt

Using the machinery of Lie group analysis,the nonlinear system of coupled Burgers-type equations is *** the infinitesimal generators in the optimal system of subalgebra of the said Lie algebras,it leads to two nonequivalent similarity transformations by using it we obtain two reductions in the form of system of nonlinear ordinary differential *** search for solutions of these systems by using the G'/G-method has yielded certain exact solutions expressed by rational functions,hyperbolic functions,and trigonometric *** figures are given to show the properties of the solutions.

关键词： symmetry method G/G-method coupled Burgers-type equations exact solutions

Direct Reduction and Exact Solutions for Generalized Variable Coefficients 2D KdV Equation under Some Integrability Conditions

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Communications in Theoretical Physics 2011年第4期55卷 551-554页

作者： m.h.m.moussa Rehabm.el-Shiekh Department of mathematics Faculty of EducationAin Shams University

Based on the closed connections among the homogeneous balance （hB） method and Clarkson-KruSkal （CK） method, we study the similarity reductions of the generalized variable coefficients 2D KdV equation. In the meantime it is shown that this leads to a direct reduction in the form of ordinary differential equation under some integrability conditions between the variable coefficients. Two different cases have been discussed, the search for solutions of those ordinary differential equations yielded many exact travelling and solitonic wave solutions in the form of hyperbolic and trigonometric functions under some constraints between the variable coefficients.

关键词： direct reduction method the generalized variable coefficients 2D KdV equation exact solutions

Prevalence and risk factors of asymptomatic hepatitis C virus infection in Egyptian children

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World Journal of Gastroenterology 2007年第12期13卷 1828-1832页

作者： mS el-Raziky m el-hawary G Esmat Am Abouzied N el-Koofy N mohsen S mansour A Shaheen m Abdel hamid h el-Karaksy Departments of Pediatrics Cairo University Cairo Egypt Departments of Tropical medicine Cairo University Cairo Egypt Tropical medicine Research Institute Cairo Egypt

AIm: To identify the prevalence, risk factors and manifestations of asymptomatic hepatitis C virus (hCV) infection in Egyptian children. mEThODS: Children at the age of 1-9 years were screened for hCV antibodies and alanine aminotransferase (ALT) levels. Every child with elevated ALT and/or detectable hCV antibodies was tested for hCV RNA by RT-PCR and compared with two negative controls for risk factors and signs and symptoms of liver ***: We screened 1042 children, six of them had elevated ALT, negative hCV antibody and positive RNA, likely representing acute hepatitis C cases. Fifteen children were hCV seropositive, 5 of them were hCV RNA positive. Asymptomatic hCV infection was present in 2.02% (positive results for either hCV antibodies or hCV-RNA or both). Symptoms such as diarrhea, abdominal pain, history of fatigue and school absence because of illness and risk factors such as dental care were significantly more common among hCV positive cases than among controls. None of the hCV positive children was diagnosed as having signs of advanced liver disease upon clinical or ultrasonographic examination. CONCLUSION: Asymptomatic hCV infection is detectable in 2.02% Egyptian children.

关键词： hepatitis C virus Child Egypt Prevalence Transfusion Risk factor