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Ocellar lamprophyre dyke bearing mineralization,Wadi Nugrus,eastern Desert,egypt:Geology,mineralogy and geochemical implications

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Chinese Journal Of Geochemistry 2010年第4期29卷 383-392页

作者： ibrahim m.e. Saleh G.m. Dawood N.A. Aly G.m. Nuclear materials Authority P.O.Box 530El-MaadiCairoEgypt

The ocellar lamprophyre dyke(eNe-WSW) is recorded at Wadi Nugrus,eastern Desert,*** cuts porphyritic biotite granites and varies in thickness from 0.5 to 1.5 m and up to 3 km in *** lamprophyre dyke has been altered,and it is characterized by porphyritic and panidiomorphic textures with plagioclase,olivine,and augite constituting the porphyritic phase in a fine groundmass of the same ***,titanite,apatite,fluorite,graphite,calcite,allanite,autunite and Fe-Ti oxides are accessory ***,chlorite and epidote are secondary *** and hematitization are *** to sub-rounded porphyritic and zoned ocelli with radiate or brush-like shapes are generally common and represent physical traps for *** ocellar features are interpreted to represent the late stage of magmatic segregation or magmatic crystallization involving two immiscible magmatic *** studies of altered lamprophyre samples,based on X-ray diffraction(XRD) and environmental scanning electron microscopy(eSem),indicate the presence of secondary uranium minerals(autunite and uranophane),associated with gold,silver,nickel,atacamite,molybdenum,pyrite and *** presence of kaolinite indicates a high tem.e.ature *** mixing of volatile fluids with meteoric water and fluid-wall rock interaction result in changes of pH and oxygen activity and deposition of base metals in reducing environs(graphite and pyrite).Precipitation of hematite probably decreased the pH of the solution and rose acidic *** sudden change in pH and tem.e.ature of the fluids would lead to destabilization of base metal complexes favoring their *** magma source of the Nugrus lamprophyre is determined to be between calc-alkaline and alkaline and it has HKCAB and shoshonitic nature and may be derived from decomposition melting of such a metasomatised lithospheric *** is a major fractional phase to account for a rapid

关键词：煌斑岩脉矿物学地球化学沙漠埃及地质学黑云母花岗岩矿化

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Recovery of some valuable elements from lamprophyre dykes in the Abu Rusheid area, Southeastern Desert, egypt

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Chinese Journal Of Geochemistry 2012年第1期31卷 64-73页

作者： Zaki D.I. Shawky N. el-Sheikh e.m. Ahmed F.Y. ibrahim m.e. Nuclear materials Authority El MaadiP.O.Box 530 CairoEgypt Chemistry Dept. Faculty of Science for GirlAl-Azhar UniversityEgypt

In the Abu Rusheid area, Southeastern Desert of egypt, polymineralized (HRees, U, Zn and Pb) lam-prophyre dykes are recently recorded. The lamprophyre dykes cut cataclastic rocks along share zones in NNW-SSe trends. The secondary U-minerals are essentially represented by uranophane, kasolite, torbernite and autunite. ex-perimental work was carried out on the lamprophyre dykes for the recovery of uranium and other valuable elements (e.g. Zn, Pb and Al) from 50 kg of technological sample. The optimum conditions were: 100 g/L sulfuric acid con-centration, 1:5 S/L (solid/liquid) and soaking for 15 days at room tem.e.ature. The leaching efficiencies for the re-covery of uranium and other elements like Al, Zn and Pb were 40, 33.6, 98.8 and 78, respectively.

关键词：有价元素煌斑岩岩脉沙漠埃及价值最佳工艺条件实验工作

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FIRST-ORDeR meTHODS FOR SOLVING THe OPTImAL STATIC H∞-SYNTHeSIS PROBLem

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Journal of Computational mathematics 2007年第6期25卷 672-689页

作者： el-Sayed m.e. mostafa Department of mathematics Faculty of Science Alexandria University Alexandria Egypt

In this paper, we consider the static output feedback （SOF） H∞-synthesis problem posed as a nonlinear semi-definite programming （NSDP） problem. Two numerical algorithms are developed to tackle the NSDP problem by solving the corresponding Karush- Kuhn-Tucker first-order necessary optimality conditions iteratively. Numerical results for various benchmark problems illustrating the performance of the proposed methods are given.

关键词： Static output feedback H∞-synthesis Semi-definite programming Nonlinear programming.

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eNHANCemeNT OF ReSISTANCe TO OXIDATIVe DeGRADATION OF NATURAL RUBBeR THROUGH LATeX DeGRADATION

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Chinese Journal of Polymer Science 1998年第2期16卷 170-175页

作者： NWANORH K.O. eNYIeGBULAm m.e. School of Physical Sciences ABIA State University P.M.B. 2000 Uturu NigeriaDepartment of Polymer & Textile Engineering Federal University of Technology P.M.B. 1526 Owerri Nigeria

A fully characterised natural rubber latex was subjected to mechanical degradation by stirring at intervals. The resistance to oxidative degradation of the different samples were studied by measuring the Plasticity retention indices (PRI). The results show that there is an enhancement of the PRI from 57% for the undegraded rubber to 79% for the one-hour degraded sample. Further degradation resulted in decrease of PRI as time of degradation increased. Therefore, the one-hour degraded sample is a special rubber with high oxidation resistance which is of great importance in engineering. (Author abstract) 9 Refs.

关键词： Plasticity Rubber Degradation Oxidation Resistance

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A CONJUGATe GRADIeNT meTHOD FOR DISCReTe-TIme OUTPUT FeeDBACK CONTROL DeSIGN

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Journal of Computational mathematics 2012年第3期30卷 279-297页

作者： e1-Sayed m.e. mostafa Department of mathematics Faculty of Science Alexandria University Alexandria Egypt

In this paper, the discrete-time static output feedback control design problem is con- sidered. A nonlinear conjugate gradient method is analyzed and studied for solving an unconstrained matrix optimization problem that results from this optimal control prob- lem. In addition, through certain parametrization to the optimization problem an initial stabilizing static output feedback gain matrix is not required to start the conjugate gradi- ent method. Finally, the proposed algorithms are tested numerically through several test problems from the benchmark collection.

关键词： Output feedback control Nonlinear conjugate gradient methods Nonlinearprogramming.

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exact Solutions of Nonlinear evolution equations in mathematical Physics Using the modified Simple equation method

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Chinese Physics Letters 2012年第6期29卷 1-4页

作者： e.m.e.Zayed S.A.Hoda ibrahim Department of mathematics Faculty of ScienceZagazig UniversityP.O.Box 44519ZagazigEgypt

The modified simple equation method is employed to construct the exact solutions involving parameters of nonlinear evolution equations via the (1+1)-dimensional modified KdV equation,and the (1+1)-dimensional reaction-diffusion *** these parameters are taken to be special values,the solitary wave solutions are derived from the exact *** is shown that the proposed method provides a more powerful mathematical tool for solving nonlinear evolution equations in mathematical physics.

关键词： equation. exact equation

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exact Solutions of Kolmogorov-Petrovskii-Piskunov equation Using the modified Simple equation method

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Acta mathematicae Applicatae Sinica 2014年第3期30卷 749-754页

作者： e.m.e.Zayed S.A.Hoda ibrahim mathematics Department Faculty of ScienceZagazig University

The modified simple equation method is employed to find the exact solutions of the nonlinear Kolmogorov-Petrovskii-Piskunov （KPP） equation. When certain parameters of the equations are chosen to be special values, the solitary wave solutions are derived from the exact solutions. It is shown that the modified simple equation method provides an effective and powerful mathematical tool for solving nonlinear evolution equations in mathematical physics.

关键词： modified simple equation method Kolmogorov-Petrovskii-Piskunov equation exact solutions solitary wave solutions

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STUDY ON THe PROPeRTIeS OF BLeND OF NATURAL RUBBeR LATeX/meTHYL meTHACRYLATe GRAFTeD RUBBeR LATeX BY GAmmA RADIATION

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Chinese Journal of Polymer Science 2007年第5期25卷 519-523页

作者： N.C. Dafader m.e. Haque F. Akhtar Nuclear and Radiation Chemistry Division Institute of Nuclear Science ＆ Technology Bangladesh Atomic Energy Commission P. O. Box 3787 Dhaka Bangladesh

Natural rubber latex （NRL） and methyl methacrylate （mmA） grafted rubber latex were blended in different ratios and irradiated at various absorbed doses by gamma rays from Co-60 source at room tem.e.ature. The tensile properties, swelling ratio and permanent set were measured. The maximum tensile strength and modulus at 500% elongation were obtained at an absorbed dose of 8 kGy. modulus increases from 6.99 mPa to 9.87 mPa for an increase in proportion of mmA grafted rubber from 40% to 60% in the blend at similar absorbed dose. elongation at break and swelling ratio decrease with increasing absorbed dose as well as the mmA grafted rubber content in the blends. The decreasing trend of permanent set is high up to 5 kGy absorbed dose, and beyond that dose, it becomes almost flat.

关键词： Natural rubber latex mmA grafted rubber latex Blend rubber Irradiation Cross-link.

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An efficient nano-adsorbent via surfactants/dual surfactants assisted ultrasonic co-precipitation method for sono-removal of monoazo and diazo anionic dyes

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Chinese Journal of Chemical engineering 2021年第12期34卷 225-236页

作者： marwa m.ibrahim Department of Chemistry Faculty of EducationAin Shams UniversityRoxy 11711CairoEgypt

To preserve the environment for civilization,we should remove the pollutants like toxic dyes by friendly and cost efficacious *** this study,the effect of surfactants or mixed surfactants on physicochemical,optical and adsorption properties of ternary mixed oxide CeO_(2)-ZrO_(2)-Al_(2) O_3(CZA) are *** ternary mixed oxide CZA was prepared by surfactants or mixed surfactants assisted ultrasonic coprecipitation *** physicochemical and optical properties are estimated by different techniques like XRD,Tem.e.X,FTIR,S_(BeT) and UV-Vis/*** CZA_T and CZA_C have hybrid shapes and high surface *** adsorption properties of ternary mixed oxides adsorbents were characterized by sono-removing anionic dyes such as Congo red(CR) and Remazol red RB-133(RR).The different factors like contact time,different dye concentrations and tem.e.atures also *** kinetics and isotherms applications showed that,the adsorption process was followed pseudo second order kinetics and the Freundlich isotherm ***,the adsorption is spontaneous and endothermic process through the thermodynamic ***,the results showed that the ternary mixed oxide nano-adsorbent(CeO_(2)-ZrO_(2)-Al_(2) O_3) is promising and functional materials for anionic dye sweep from wastewater.

关键词： CeO_(2)-ZrO_(2)-Al_(2)O_3 Surfactants Ultrasonic co-precipitation method Optical properties Wastewater Adsorption

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Oxidation Resistance of the Aluminide Coating Formed on Carbon Steels

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Journal of materials Science & Technology 1997年第5期13卷 383-388页

作者： Soliman, H.m. mohamed, K.e. Abd el-Azim, m.e. Hammad, F.H. metallurgy Dept. Atomic Energy Authority Cairo Egypt

Low and medium carbon steels were aluminized by the pack aluminizing technique using halideactivated pure-Al and Fe-Al packs. The effect of mixture composition, aluminizing tem.e.atureand time and C content of the steel substrate on the structure and thickness of the aluminidelayer, and on the oxidation resistance was investigated. The optimum oxidation resistance canbe achieved with a low carbon steel substrate when the intermetallic phases Fe3Al and FeAlform the surface of the aluminide layer. In this case, the Al concentration at the surface of thealuminide coating is at least ≥15 wt pct. Formation of high Al concentration phases (FeAl3 andFe2Al5) during aluminizing should be avoided as they tend to embrittle the aluminide layer andreduce its oxidation resistance.

关键词： OO Figure Oxidation Resistance of the Aluminide Coating Formed on Carbon Steels

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