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Journal of Natural Gas Chemistry 2008年第4期17卷 337-343页

作者： Ahmed K.Aboul-Gheit Ahmed E.Awadallah Salah M.El-Kossy abdel-lateef h.mahmoud Process Development Division Egyptian Petroleum Research Institute Faculty of Science Department of ChemistryMNF University Ageeba Petroleum Co.

Natural gas conversion to petrochemicals, principally, benzene, naphthalene, toluene, as well as ethylene under non-oxidative conditions was examined in a fixed bed flow reactor at 700 ℃ and gaseous hourly space velocity （GhSV） of 1500 ml·g ^-1·h^-1 at time-on-stream ranging from 5 rain to 4 h using catalysts containing 6.0%Mo/h-ZSM-5 promoted with Pd or Ir metal. The catalysts were characterized by XRD, TPD, and TGA. The addition of Pd or Ir to 6%Mo/h-ZSM-5 catalyst promoted ethylene production but inhibited the cyclization reaction to aromatics owing to the strong interaction between these noble metals and the framework Al species, which were attached to the acid sites during the impregnation process. Coke deposition on the catalysts was found to decrease upon addition of 0.5wt% of Pd or Ir to 6%Mo/h-ZSM-5 catalyst owing to the hydrogenating activity of these metals.

关键词： natural gas methane benzene ethylene molybdenum Pd Ir h-ZSM-5

Influence of potassium fertilization and foliar application of zinc and phosphorus on growth,yield components,yield and fiber properties of Egyptian cotton(Gossypium barbadense L.)

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Journal of Plant Ecology 2008年第4期1卷 259-270页

作者： Zakaria M.Sawan mahmoud h.mahmoud Amal h.El-Guibali Cotton Research Institute Agricultural Research CenterMinistry of Agriculture and Land Reclamation9 Gamaa StreetGiza 12619Egypt Soils Water and Environment Research InstituteAgricultural Research CenterMinistry of Agriculture and Land Reclamation9 Gamaa StreetGiza 12619Egypt

Aims Supplying optimal quantities of mineral nutrients to growing crop plants is one way to improve crop *** need to be used rationally in order to avoid a negative ecological impact and undesirable effects on the sustainability of agricultural production *** application of nutrients also affects the farmer’s *** order to calculate the amount of fertilizer to be applied to crops,it is necessary to develop recommendation programmers that adjust nutrient rates to crop *** Experiments in two successive seasons were conducted to investigate the effect of K fertilization and foliar application of Zn and P on yield and fiber properties of cotton *** ***(0.0 and 47.4 kg of K ha^(-1))was soil applied,while chelated zinc(0.0 and 57.6 g of Zn ha^(-1),applied twice at 70 and 85 days after sowing‘DAS’)and phosphorus(0.0,576,1152 and 1728 g of P ha^(-1),applied twice at 80 and 95 DAS)were applied to the *** findings Dry matter yield,total chlorophyll concentration,K,Zn and P uptake per plant,number of opened bolls per plant,boll weight,seed index,lint index,seed cotton yield per plant,seed cotton and lint yield ha^(-1) and earliness of harvest increased with the application of K,Zn and *** generally had no significant effect on lint percentage and fiber properties,with exceptions,for micronaire reading and flat bundle strength,and uniformity ratio,where the mean values of these characters were significantly increased over the untreated control by applying K,and for the micronaire reading in the first season,when applying P at 1728 g ha^(-1),and uniformity ratio in the second season,when applying Pat 1152 and 1728 g ha^(-1),where the mean values of these characters were significantly increased over the untreated control by applying *** the conditions of this study,applying K fertilization at 47.4 kg ha^(-1) combined with spraying cotton plants with zinc at 57.6 g ha^(-1) and also with P at

关键词： cotton fiber properties phosphorus potassium yield and yield components zinc

Martensitic transformation and magnetic properties of aged Ni-Fe-Ga-Ti shape memory alloy

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International Journal of Minerals,Metallurgy and Materials 2013年第9期20卷 867-873页

作者： Nader El-Bagoury mahmoud Mohamed hessien Magdy abdel Wahab Kaseem Chemistry Department Faculty of Science TAIF University P.O. Box 888 El-Haweyah El-Taif Saudi Arbia Central Metallurgical Research and Development Institute (CMRDI) P.O. Box 87 Helwan Cairo Egypt head of National Authority for Quality of Education Assurance and Accreditation Nasr City Cairo P.O. Box 11461 Egypt

This article reports the effect of ageing on the microstructure, martensitic transformation, magnetic properties, and mechanical properties of Ni51FelsGa27Ti4 shape memory alloy. There are five specimens of this alloy aged at 573 up to 973 K for 3 h per each. This range of ageing temperature greatly affects the microstructure of the alloy. As the ageing temperature increased from 573 up to 973 K, the microstructure of Ni51FelsGa27Ti4 alloy gradually changed from the entirely martensitic matrix at 573 K to the fully austenitic microstructure at 973 K. The volume fraction of precipi- tated Ni3Ti particles increased with the ageing temperature increasing from 573 to 773 K. Further increasing the ageing temperature to 973 K decreased the content of Ni3Ti in the microstructure. The martensitic transformation tempera- ture was decreased steadily by increasing the ageing temperature. The magnetization saturation, remnant magnetization, and coercivity increased with the ageing temperature increasing up to 773 K. A further increase in ageing temperature decreased these raagnetic properties. Moreover, the hardness values were gradually increased at first by increasing the ageing temperature to 773 K, and then dramatically decreased to the lowest value at 973 K.

关键词： magnetic materials shape memory effect ageing microstructure martensitic transformations magnetic properties hardness

Group solution for an unsteady non-Newtonian hiemenz flow with variable fluid properties and suction/injection

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Chinese Physics B 2014年第9期23卷 43-53页

作者： h.M.El-hawary Mostafa A.A.mahmoud Reda G.abdel-Rahman Abeer S.Elfeshawey Department of Mathematics Faculty of ScienceAssuit University Department of Mathematics Faculty of ScienceBenha University

The theoretic transformation group approach is applied to address the problem of unsteady boundary layer flow of a non-Newtonian fluid near a stagnation point with variable viscosity and thermal conductivity. The application of a two- parameter group method reduces the number of independent variables by two, and consequently the governing partial differential equations with the boundary conditions transformed into a system of ordinary differential equations with the appropriate corresponding conditions. Two systems of ordinary differential equations have been solved numerically using a fourth-order Runge-Kutta algorithm with a shooting technique. The effects of various parameters governing the problem are investigated.

关键词： non-Newtonian fluid stagnation point two-parameter group method variable viscosity

Self-phase modulation via similariton solutions of the perturbed NLSE Modulation instability and induced self-steepening

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Communications in Theoretical Physics 2022年第8期74卷 41-50页

作者： h I abdel-Gawad Department of Mathematics Faculty of Science Cairo University Egypt

The perturbed nonlinear Schrodinger equation(PNLSE)describes the pulse propagation in optical fibers,which results from the interaction of the higher-order dispersion effect,self-steepening(SS)and self-phase modulation(SPM).The challenge between these aforementioned phenomena may lead to a dominant one among *** is worth noticing that the study of modulation instability(MI)leads to the inspection of dominant phenomena(DPh).Indeed,the MI triggers when the coefficient of DPh exceeds a critical value and it may occur that the interaction leads to wave *** PNLSE is currently studied in the literature,mainly on finding traveling wave ***,we are concerned with analyzing the similarity solutions of the *** exact solutions are obtained via introducing similarity transformations and by using the extended unified *** solutions are evaluated numerically and they are shown *** is observed that the intensity of the pulses exhibits self steepening which progresses to shock soliton in ultrashort time(or near t=0).Also,it is found that the real part of the solution exhibits self-phase modulation in *** study of(MI)determines the critical value for the coefficients of SS,SPM,or high dispersivity to occur.

关键词： Perturbed NLSE steepening self–phase modulation extended unified method

Field and reverse field solitons in waveoperator nonlinear Schrödinger equation with space-time reverse: Modulation instability

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Communications in Theoretical Physics 2023年第6期75卷 39-50页

作者： h I abdel-Gawad Mathematics Department Faculty of Science Cairo University GizaEgypt

The wave-operator nonlinear Schrödinger equation was introduced in the ***,nonlocal space-time reverse complex field equations were also recently *** in this area were focused on employing the inverse scattering method and Darboux ***,we present an approach to find the solutions of the wave-operator nonlinear Schrödinger equation with space and time reverse(W-O-NLSE-STR).It is based on implementing the unified method together with introducing a conventional formulation of the ***,a field and a reverse field may be ***,for deriving the solutions of W-O-NLSE-STR,it is evident to distinguish two cases(when the field and its reverse are interactive or not-interactive).In the non-interactive and interactive cases,exact and approximate solutions are *** both cases,the solutions are evaluated numerically and they are displayed *** is observed that the field exhibits solitons propagating essentially(or mainly)on the negative space variable,while those of the reverse field propagate on the other side(or vice versa).These results are completely novel,and we think that it is an essential behavior that characterizes a complex field system with *** the other hand,they may exhibit right and left cable patterns(or vice versa).It is found that the solutions of the field and its reverse exhibit self-phase modulation by solitary *** the interactive case,the pulses of the field and its reverse propagate in the whole *** analysis of modulation stability shows that,when the field is stable,its reverse is unstable or both are *** holds whenever the polarization of the medium is selfdefocusing.

关键词： wave-operator nonlinear Schrödinger equation space-time reverse unified method

Distribution of Some Elements in the Egyptian Black Sands from Abu Khashaba Beach Area

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Journal of Analytical Sciences, Methods and Instrumentation 2013年第1期3卷 62-66页

作者： h. h. mahmoud A. M. abdel-lateef A. M. Attiah Central Laboratory for Elemental and Isotopic Analysis Nuclear Research Center Cairo Egypt Central Laboratory for Elemental and Isotopic Analysis Nuclear Research Center Cairo Egypt Physics Department Faculty of Science and Human Studies Shaqra University Shaqra KSA.

Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) technique was used to determine the concentrations of titanium (Ti), vanadium (V), Chromium (Cr), Manganese (Mn), iron (Fe), zinc (Zn), arsenic (As), zirconium (Zr), cadmium (Cd) and hafnium (hf) in black sands samples. 18 black sands samples were collected from the Mediterranean coast-Abu Khashabou Rosetta area, Egypt. Alkaline fusion procedure using mixture of Li-meta borate and tetra borate was used for the digestion of black sands samples. The average concentrations of Ti, V, Cr, Mn, Fe, Zn, As, Zr, Cd and hf were 435.06 ppm, 322.32 ppm, 2515.03 ppm, 596.45 ppm, 185894 ppm, 249.95 ppm,309.32 ppm, 1077.26 ppm, 33.56 ppm and 3520.32 ppm, respectively. The procedure was tested with Basalt hawaiian Volcanic Observatory (BhVO-2) standard reference material.

关键词： Alkaline Fusion Black Sand ICP-MS Rosetta Branch

Distributed h2/h∞ Filter Design for Discrete-Time Switched Systems

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IEEE/CAA Journal of Automatica Sinica 2020年第1期7卷 158-168页

作者： Nezar M.Alyazidi Magdi S.mahmoud Systems Engineering Department King Fahd University for Petroleum and Minerals

This paper addresses an infinite horizon distributed h2/h∞ filtering for discrete-time systems under conditions of bounded power and white stochastic signals. The filter algorithm is designed by computing a pair of gains namely the estimator and the coupling. herein, we implement a filter to estimate unknown parameters such that the closed-loop multi-sensor accomplishes the desired performances of the proposed h2 and h∞ schemes over a finite horizon. A switched strategy is implemented to switch between the states once the operation conditions have changed due to disturbances. It is shown that the stability of the overall filtering-error system with h2/h∞ performance can be established if a piecewise-quadratic Lyapunov function is properly constructed. A simulation example is given to show the effectiveness of the proposed approach.

关键词： Bounded power stochastic disturbance discretetime systems h2/h∞ filtering infinite horizon multi-sensor switched systems

Geometric Phase of a Coupled System

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Communications in Theoretical Physics 2004年第5X期42卷 672-674页

作者： h.S.abdel-Aziz MathematicsDepartment FacultyofScienceSouthValleyUniversitySohagEgypt

In this contribution, my main attention is paid to the study of the geometric phase ora two-level *** expansion of the eigenvalue and analytic information are obtained. The results are illustrated with an application ... 详细信息

关键词：几何相位二平面偏微分方程量子论

Valorization of sustainable vegetable oil deodorizer distillate as a novel fatliquor

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Collagen and Leather 2023年第3期5卷 60-72页

作者： El-Shahat h.A.Nashy Adel Gabr abdel-Razek Minar mahmoud M.hassanein Ghada A.Abo-Elwafa hamed Elsayed Chemical Industries Research Institute National Research CentreDokkiCairo 12622Egypt Department of Fats and Oils National Research CentreDokkiCairo 12622Egypt

The deodorizer distillate(DD)is a byproduct of vegetable oil processing industry and is rich in functional bioactive *** study aimed to employ phosphorylation modification for DD to produce a new sustainable *** bioactive ingredients in DD,namely fatty acids,sterols,and tocopherols,were determined by using hPLC and *** results revealed that the DD sample contained a high percentage of unsaturated fatty acids(72.3%)and high levels ofγandδ-tocopherols(54.8%and 31.60%,respectively).Mechanical parameters(tensile strength,elongation at break,and tear strength)of leather were improved after being treated with the prepared fatliquor ***,SEM showed that the texture of the fatliquored leather had been remarkably ***,the fatliquored leather possessed effective antibacterial effect against the specified+ve,-ve bacteria,and Candida albicans *** strength,fullness,soft handle,and elasticity of leather were all improved,and the grain of leather was protected from becoming loose after drying.

关键词： Vegetable oil Deodorizer distillate Bioactive components Fatliquor Phosphorylation Chrome tanned leather