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Entropy Generation for Flow and Heat Transfer of Sisko-Fluid Over an Exponentially Stretching Surface

Computers, Materials & Continua 2020年第1期62卷 37-59页

作者： Mohamed abd el-Aziz A.M.Aly Department of Mathematics Faculty of ScienceKing Khalid UniversityAbha61411Saudi Arabia Department of Mathematics Faculty of ScienceHelwan UniversityHelwan-Cairo11795Egypt Department of Mathematics Faculty of ScienceSouth Valley UniversityQena83523Egypt

In the present study,the effects of the magnetic field on the entropy generation during fluid flow and heat transfer of a Sisko-fluid over an exponentially stretching surface are *** similarity transformations are used to transfer the governing partial differential equations into a set of nonlinear-coupled ordinary differential ***-Kutta-Fehlberg method is used to solve the governing *** effects of magnetic field parameter,local slip parameterλ,generalized Biot numberγ,Sisko fluid material parameter,Eckert number Ec,Prandtl number Pr and Brinkman number Br at two values of power law index on the velocity,temperature,local entropy generation number N_(G) and Bejan number Be are ***,the tabular forms for local skin friction coefficient and local Nusselt number under the effects of the physical parameters are *** current results are helpful in checking the entropy generation for *** is found that,an extra magnetic field parameter makes higher Lorentz force that suppresses the *** shear thinning fluids(nelocity *** entropy generation number is more for larger generalized Biot number,magnetic field parameter and Brinkman *** local skin friction coefficient increases as magnetic field parameter and material parameter are increase and it decreases as local slip parameter *** local Nusselt number decreases as magnetic field parameter,local slip parameter and Eckert number are increase,while it increases as material parameter,generalized Biot number and Prandtl number are increase.

关键词： Boundary layer entropy generation exponentially stretching surface magnetic field sisko-fluid

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MHD Boundary Layer Flow of a Power-Law Nanofluid Containing Gyrotactic Microorganisms Over an Exponentially Stretching Surface

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Computers, Materials & Continua 2020年第2期62卷 525-549页

This study focusses on the numerical investigations of boundary layer flow for magnetohydrodynamic(MHD)and a power-law nanofluid containing gyrotactic microorganisms on an exponentially stretching surface with zero nanoparticle mass flux and convective *** nonlinear system of the governing equations is transformed and solved by Runge-Kutta-Fehlberg *** impacts of the transverse magnetic field,bioconvection parameters,Lewis number,nanofluid parameters,Prandtl number and power-law index on the velocity,temperature,nanoparticle volume fraction,density of motile microorganism profiles is *** addition,the impacts of these parameters on local skin-friction coefficient,local Nusselt,local Sherwood numbers and local density number of the motile microorganisms are *** results reveal that the power law index is considered an important factor in this *** to neglecting the buoyancy force term,the bioconvection and nanofluid parameters have slight effects on the velocity *** resultant Lorentz force,from increasing the magnetic field parameter,try to decrease the velocity profiles and increase the rescaled density of motile microorganisms,temperature and nanoparticle volume fraction ***,an augmentation of power-law index drops the reduced local skin-friction and reduced Sherwood number,while it increases reduced Nusselt number and reduced local density number of motile microorganisms.

关键词： Bioconvection gyrotactic microorganisms magnetohydrodynamic nanofluid boundary layer power-law

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Fractional Optimal Control of Navier-Stokes Equations

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Computers, Materials & Continua 2020年第8期64卷 859-870页

作者： abd-Allah Hyder M.el-Badawy King Khalid University College of ScienceDepartment of MathematicsP.O.Box 900461413AbhaSaudi Arabia Department of Engineering Mathematics and Physics Faculty of EngineeringAl-Azhar UniversityCairo11371Egypt Mathematics Department Al-Azhar UniversityCairoEgypt

In this paper,the non-stationary incompressible fluid flows governed by the Navier-Stokes equations are studied in a bounded *** study focuses on the time-fractional Navier-Stokes equations in the optimal control subject,where the control is distributed within the domain and the time-fractional derivative is proposed as Riemann-Liouville *** addition,the control object is to minimize the quadratic cost *** using the Lax-Milgram lemma with the assistance of the fixed-point theorem,we demonstrate the existence and uniqueness of the weak solution to this ***,for a quadratic cost functional subject to the time-fractional Navier-Stokes equations,we prove the existence and uniqueness of optimal ***,via the variational inequality upon introducing the adjoint linearized system,some inequalities and identities are given to guarantee the first-order necessary optimality conditions.A direct consequence of the results obtained here is that when a→1,the obtained results are valid for the classical optimal control of systems governed by the Navier-Stokes equations.

关键词： Optimal control lax-milgram lemma fixed point theorem navier-stokes equations

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Physio-biochemical and nutrient constituents of peanut plants under bentazone herbicide for broad-leaved weed control and water regimes in dry land areas

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Journal of Arid Land 2020年第4期12卷 630-639页

作者： Hani S SAUDY Ibrahim M el–METWALLY Goma A abd el–SAMAD Agronomy Department Faculty of AgricultureAin Shams University68–Hadayek Shoubra 11241CairoEgypt Botany Departments National Research CentreEl–Behos St.Dokki 12622CairoEgypt

The abundance of broad-leaved weeds in peanut fields represents the handicap in weed management programs, since limited specific herbicides can be recommended to control them. Moreover, the physio-biochemical constituents and nutritional status in peanut plants as affected by available herbicides, i.e., bentazone under water stress conditions are not well known. Therefore, field trials were conducted during the growing seasons in 2016 and 2017 to investigate the interactional impact of irrigation levels(I_(50), I_(75) and I_(100), representing irrigation by 50%, 75% and 100% of crop evapotranspiration, respectively) and weed control practices(bentazone, bentazone+hoeing once, hoeing twice and weedy check as control) on dominant broad-leaved weeds as well as peanut physiological and agronomic traits. Result indicated that the efficiency of weed control for each weeded treatment under I_(50) significantly equaled with its counterpart under I_(75) or I_(100). Bentazone+hoeing once diminished weed biomass by 89.3% and enhanced chlorophyll content of peanut plants by 51.2%. Bentazone relatively caused a reduction in carotenoides. Hoeing twice and bentazone+hoeing once under I_(100) in both growing seasons as well as hoeing twice under I_(75) in 2017 were the superior combinations for boosting pod yield of peanut plants. Treatment of bentazone+hoeing once and I_(75) recorded the lowest reduction in N utilization percentage and the highest increase in potassium utilization percentage of peanut plants. eliminating weeds enhanced water use efficiency by 37.8%, 49.6% and 34.7% under I_(50), I_(75) and I_(100), respectively. In conclusion, peanut seems to be tolerant to bentazone at moderate water supply, thus it can be safely used in controlling the associated broad-leaved weeds.

关键词： biochemical traits drought nutritional status peanut productivity weed growth

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Structural Deformation Monitoring and Analysis of Highway Bridge Using Accurate Geodetic Techniques

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Engineering（科研） 2015年第8期7卷 488-498页

作者： ashraf abd el-Wanis Beshr Public Works Department Faculty of Engineering Mansoura University Mansoura City Egypt

As the new materials and technologies are increasingly applied to construction of civil infrastructures such bridges, dam and tunnels, the need for structural monitoring systems, maintenance and restoration becomes more important and vital. Bridges are widespread in every society and affect its human, social, economical and cultural aspects. Measurements and monitoring of the structural deformation of highway bridges have an essential role in structural safety. This paper investigates an integrated monitoring system for estimation of the deformation behavior of one of the important reinforced bridges in Egypt. The applied data for analysing the deformation of any structure from geodetic observations are the coordinates of several monitoring points distributed on the structure itself. The coordinates of these points are calculated with respect to control fixed points. So any deviations in the control points coordinates between the two successive epochs of observations will affect the values of structural deformation. To overcome this shortage, applying the multi-parameter transformation will be studied in this paper for structural health monitoring of bridges. Statistical tests using F-Fisher criterion with a confidence level of 98% of the geodetic observations for bridge deformation values are also presented. The results of the practical measurements, analysis of the interesting deformation technique and traffic flow around the studied highway bridge are also presented. The resulting structural deformation values from statistical tests provide a significant improvement of understanding and prediction the structure deformation values of highway bridges.

关键词： Bridges Monitoring Statistical Tests Transformation Deformation

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Sedimentation Processes at the Navigation Channel of the Liquefied Natural Gas (LNG) Port, Nile Delta, Egypt

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International Journal of Geosciences 2010年第1期1卷 14-20页

作者： Essam abd el-halim Mohamed Deabes Physical Oceanography Department Coastal Research Institute (CoRI)

Liquefied Natural Gas (LNG) port is located at Abu Qir Bay on the northwestern coast of the Nile delta, Egypt. The port was constructed in 2004 to export liquefied natural gas worldwide. The offshore basins of this port including the turning and berthing areas (15-m depth) are connected to the deep water by a 15-m depth dredged channel that extends 4 km offshore. However, the navigation channel and its contiguous basins have experienced problematic shoaling that might affect the navigation activities of gas tankers. Sedimentation processes have been investigated by analyses of waves, currents, bathymetry, grain size of seabed and channel dimensions. Sedimentation rates are estimated using a developed numerical model. Sedimentation rate fluctuates between 0.048 × 106 m3/month and 0.388 × 106 m3/month, with an annual sedimentation rate of 1.977 × 106 m3/yr. The variance in the sedimentation rates between winter and summer resulted in increasing of current speed and direction flowing towards offshore. The sedimentation process is influenced by the temporal variability in the direction and intensity of the predominant waves, currents, orientation of navigation channel, basin breakwaters, seafloor morphology and sediment sources. Due to the geographic location of LNG port it lays within a sediment sink for sediments supplied from different alternating directions by several pathways, flowing towards the N-W, S-W, N-E, and S-E quadrants. Most of these currents components are substantially effective in transporting fine-grained sediment towards the navigation channel axis and contiguous basins. Together with these currents, the predominant NW and SE waves acting to agitate and stirrup sediments in the vicinity of the port, and thereby accelerating sedimentation rates.

关键词： Sedimentation Rate Nile Delta Navigation Channel Bed Load Suspended Load and Sediment Transport

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Nano-crystallites Imine-based Copper(II) Complexes as Mimetics for Copper Oxidase Proteins: Synthesis,Characterization,DFT and Oxidase Mimicking Activity

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Chemical Research in Chinese Universities 2024年第6期40卷 1068-1081页

作者： ALHADHRAMI abdulrahman RAMADAN abd el-Motaleb FATHY Ahmed Department of Chemistry College of ScienceTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Chemistry Department Faculty of ScienceKafr El-Sheikh UniversityKafr El-SheikhEgypt Chemistry Department Faculty of ScienceZagazig UniversityZagazigEgypt

Three tridentate imine ligands containing N2S donors were synthesized via Schiff condensation between derivatives of both amino triazine and 2-carbonyl *** reaction of these ligands with CuCl2 in a molar ratio of 1:1 provides three Cu(II) complexes with the general formula [CuLn·Cl_(2)].Analytical,electrical,magnetic,and spectroscopic studies were used to assign the molecular formulae of these metallic *** function theory (DFT) calculations confirmed the structural analysis results obtained from spectroscopic *** various characterization techniques used demonstrated the penta-coordinated slightly distorted square pyramidal structure for the present Cu(II) complexes 1,2,and *** of cyclic voltammetry were done in methanol to define the electrochemical behavior of the current Cu(II) *** biomimetics of catechol oxidase (C.O.);phenoxazinone synthase (PHS) have been studied in the aerobic oxidation of some phenolic substrates,such as 3,5-di-tert-butylcatechol (3,5-DTBCH2);ortho-aminophenol (o-APH3).The three candidate oxidase mimetics showed promising activity in the order 3 > 1 > *** catalytic activity related to the structural properties of existing oxidase mimetics was *** driving force (-ΔG°) controlling the redox reactions of the present biomolecules was calculated from the redox data of Cu(II) complexes 1,2,and *** potential catalytic reaction pathway for the oxidation of the studied phenolic substrates was discussed.

关键词： Nano-crystallite Imine-based copper(II)complex Mimetics of copper oxidase protein Synthesis and characterization Density function theory(DFT)calculation

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Effective damping of local low frequency oscillations in power systems integrated with bulk PV generation

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Protection and Control of Modern Power Systems 2021年第1期6卷 512-524页

作者： Ahmed Hesham abd el-Kareem Mohamed abd elhameed Mahmoud M.elkholy Operation Engineer at New Capital Power Plant New Capital CityEgypt electrical Power and Machines Department Faculty of EngineeringZagazig UniversityZagazigEgypt

High penetration of renewable sources into conventional power systems results in reduction of system inertia and noticeable low-frequency oscillations (LFOs) in the rotor speed of synchronous generators. In this paper, we propose effective damping of LFOs by incorporating a supplementary damping controller with a photovoltaic (PV) generating station, where the parameters of this controller are coordinated optimally with those of a power system stabilizer (PSS). The proposed method is applied to damp local electromechanical modes by studying a system comprising a synchronous generator and a PV station connected to an infinite bus. The PV station is modeled following the instructions of the Western electricity Coordinating Council. The problem is modeled as an optimization problem, where the damping ratio of the electromechanical modes is designed as the objective function. Constraints including upper and lower limits of decision parameters and damping ratio of other modes are considered by imposing penalties on the objective function. Different optimization algorithms are used to pursue the optimal design, such as political, improved gray wolves and equilibrium optimizers. The results validate the effectiveness of the proposed controller with PSS in damping local modes of oscillations.

关键词： Low frequency oscillations Damping controller PV WECC

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Response of seed yield and fatty acid compositions for some sunflower genotypes to plant spacing and nitrogen fertilization

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Information Processing in Agriculture 2017年第3期4卷 241-252页

作者： Mohamed Ali abd el-Satar Asmaa abd-el-halime Ahmed Tamer Hassan Ali Hassan Oil Crops Research Department Field Crops Research InstituteAgricultural Research Center9 El-Gamaa St.GizaEgypt

A field experiment was conducted at the experiment Farm of Kafr-el-Hamam Research Station,Zagazig,Sharkia Governorate,Agricultural Research Center,Egypt during the two successive summer seasons of 2015 and 2016 to achieve the highest yield and good oil quality of three tested sunflower *** both seasons,the experiment was conducted using the split split plot design in randomized complete block design with three replicates arrangement keeping plant spaces(15,20 and 25 cm apart between hills)in main plots,nitrogen fertilization levels(15,30 and 45 N fad.^-1)in sub plots and sunflower genotypes(Giza 102,Sakha 53 and promising line of L120)in sub sub *** and quality traits were significantly influenced by plant spaces,nitrogen fertilization levels and genotypes as well as interactions in both seasons and their combined *** wider plant spacing of 25 cm seems to be a good compromise between the highest seed yield fad.^-1 and good acid composition of *** increasing of nitrogen fertilization level had a positive reflected on yield and desirable acid composition of *** 53 was ranked in the first order in stem diameter,head diameter,100-seed weight,seed weight plant^-1,flowered late and hence seed yield fad.^-1 as well as seed oil content whereas,Giza 102 characterized with its contained the highest proportion of oleic and linoleic unsaturated fatty *** highest values of head diameter,100-seed weight,seed weight plant^-1 and hence seed yield fad.^-1 as well as the highest proportion of oleic and linoleic unsaturated fatty acids composition were obtained by grown sunflower *** 53 at wider spacing of 25 cm with application of nitrogen fertilization levels of 45 N fad.^-*** and path analyses revealed that 100-seed weight and head diameter had the highest direct and indirect influence on seed weight plant1,at the same time also,oleic acid content and linoleic acid content had the highest direct and indirect effect inf

关键词： Sunflower Plant spacing Nitrogen fertilization Genotypes Seed yield Fatty acids

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Permutation-substitution image encryption scheme based on a modified chaotic map in transform domain

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Journal of Central South University 2017年第9期24卷 2049-2057页

作者： Ramadan Noha Ahmed Hossameldin H el-khamy Said E abd el-Samie Fathi E Faculty of electronic Engineering Menofia University Faculty of Engineering Alexandria University

A new chaotic image encryption scheme based on permutation and substitution in the Fourier domain is *** Fourier Transform(FRFT)is used before the encryption scheme to get a large degree of *** permutation is achieved by Baker map and the substitution by a key-related-to-plain-image algorithm based on the modified Logistic *** of the Logistic map is developed to increase the space of the encryption key,and hence increase the *** key of the encryption algorithm dependents on the plain image,and thus,the cipher image is sensitive to both the initial key and the plain image to resist known-plaintext and chosen plaintext *** key space is large and hence the algorithm can effectively resist brute-force *** proposed scheme is examined using different performance evaluation metrics and the results prove that the proposed scheme is highly secure,and it can effectively resist different attacks.

关键词： Backer map chaotic encryption fractional Fourier transform (FRFT) modified Logistic map

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