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Journal of Magnesium and Alloys 2023年第9期11卷 3231-3240页

作者： Saeed ahmed State key Laboratory of Chemical Resource Engineering College of ChemistryBeijing University of Chemical TechnologyBeijing 100029China Department of Chemistry The University of LahoreLahore 54590Pakistan Department of Chemistry University of ChakwalPakistan

In this work, a series of hierarchical flower-like magnesium oxide(MgO) adsorbents were successfully fabricated in a cetyltrimethylammonium bromide(CTAB) assisted solvothermal route using hexamethylenetetramine(HMTA) as a precipitating agent. Effects of CTAB feeding amount on the structure, morphology, pore structure, and corresponding adsorption behavior were investigated. The hierarchical gardenias flower-like MgO demonstrated a surface area of 336.54 m^(2)·g^(-1) at a minimum ratio of the CTAB/Mg^(2+)was 0.02 in the reaction system. The hierarchical MgO phosphate removal capacity was 348.32 mg·g^(-1), which followed the pseudo-second-order and Freundlich isotherm model obtained from the large surface area and appropriate pore size. The value of n also suggests the feasible nature of phosphate adsorption under the examined conditions. Indeed, this CTAB assisted solvothermal method can provide a new understanding to tune the desired properties of a material by merely adjusting the reaction parameters of MgO.

关键词： Adsorption CTAB-assisted Magnesium oxide Phosphate removal Solvothermal

Load Frequency Control of Multi-interconnected Renewable Energy Plants Using Multi-Verse Optimizer

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Computer Systems Science & Engineering 2021年第5期37卷 219-231页

作者： Hegazy Rezk Mohamed A.Mohamed ahmed A.Zaki Diab n.kanagaraj College of Engineering at Wadi Addawaser Prince Sattam Bin Abdulaziz UniversityWadi Addawaser11991Saudi Arabia Electrical Engineering Department Faculty of EngineeringMinia UniversityMinia61111Egypt

A reliable approach based on a multi-verse optimization algorithm(MVO)for designing load frequency control incorporated in multi-interconnected power system comprising wind power and photovoltaic(PV)plants is presented in this *** has been applied for optimizing the control parameters of the load frequency controller(LFC)of the multi-source power system(MSPS).The MSPS includes thermal,gas,and hydro power plants for energy ***,the MSPS is integrated with renewable energy sources(RES).The MVO algorithm is applied to acquire the ideal parameters of the controller for controlling a single area and a multi-area MSPS integrated with *** link is utilized in shunt with AC multi-areas interconnection tie *** proposed scheme has achieved robust performance against the disturbance in loading conditions,variation of system parameters,and size of step load perturbation(SLP).Meanwhile,the simulation outcomes showed a good dynamic performance of the proposed controller.

关键词： Load frequency control multi-verse optimization multi-area power system renewable energy sources

Mapping Structurally Controlled Alterations Sparked by Hydrothermal Activity in the Fatira–Abu Zawal Area,Eastern Desert,Egypt

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Acta Geologica Sinica(English Edition) 2023年第2期97卷 662-680页

作者： Mohamed BADAWI Mahmoud ABDELATIF Ali SHEBL Farid MAkROUM ahmed SHALABY norbert néMETH Institute of Exploration Geosciences University of MiskolcMiskolc 3515Hungary Department of Geology Mansoura UniversityMansoura 35516Egypt Department of Geology South Valley UniversityQena 83523Egypt Department of Mineralogy and Geology University of DebrecenDebrecen 4032Hungary Department of Geology Tanta UniversityTanta 31527Egypt

The Eastern Desert of Egypt suffered a protracted period of deformation triggered by cratonization of the new juvenile crust known as the Arabian nubian Shield(AnS),which has been proposed for potential gold discoveries associated with the corresponding tectonic *** Fatira area,on the border of Egypt’s northern and Central Eastern Deserts,is covered with metavolcanic rocks twisted by a dextral relocation of the Fatira Shear Zone(FSZ)relative to the Barud magmatic *** recent study evaluated many deformed post-orogenic granitic intrusions and felsite dikes associated with promising mineralization localities,notably orogenic gold *** combination of various field observations and remote sensing data,followed by the analysis of aeromagnetic enhanced maps,allowed the differentiation of distinct lithologies,structural features,and hydrothermal alterations in the study ***,the integrated results obtained from the different interpretation techniques are utilized to identify and confirm the previously supposed mineralized localities in the Fatira and Abu Zawal areas and predict other matched *** final ASTER,Sentinel 2 hydrothermal alteration,and orientation entropy heat maps demonstrate the association between these mineralized regions and major structures related to the FSZ late stage of deformation rather than other structures studied throughout the area of interest.

关键词： gold granite island arc association Pan-African Orogeny Egypt

Heat Transfer Analysis of MHD Power Law nano Fluid Flow through Annular Sector Duct

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Journal of Thermal Science 2020年第1期29卷 169-181页

作者： ahmed Farhan IQBAL Mazhar School of natural Sciences National University of Science and Technology

Flow and heat transfer analysis of an electrically conducting MHD power law nano fluid is carried out through annular sector duct,under the influence of constant pressure *** types of nano particles(*** and TiO2)are used in power law nano *** implicit procedure,(SIP)is used to simulate the discretized coupled algebraic *** has been observed that volume fraction of nano particles,ϕand magnetic field parameter,Ha are favourable for the heat transfer rate,however,both resist the fluid *** of applied uniform transverse magnetic field exceeds in the case of shear thickening fluids(i.e.n>1)by increasing the value of Ha as compared to that in shear thinning fluids(i.e.nnhancement in heat transfer rate is comparably more in shear thickening ***,comparable limiting case study with published result is also carried out in this research paper.

关键词： electrically conducting power law nano fluid Cu nano particles TiO2 nano particles shear thickening fluid shear thinning fluid heat transfer rate friction factor

Self-Dual Weak Hopf Algebras

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Acta Mathematica Sinica,English Series 2008年第12期24卷 1935-1948页

作者： Munir ahmed Department of Mathematics Zhejiang University Hangzhou Zhejiang 310027 P. R. China

In this paper, we define the notion of self-dual graded weak Hopf algebra and self-dual semilattice graded weak Hopf algebra. We give characterization of finite-dimensional such algebras when they are in structually simple forms in the sense of E. L. Green and E. n. Morcos. We also give the definition of self-dual weak Hopf quiver and apply these types of quivers to classify the finite- dimensional self-dual semilattice graded weak Hopf algebras. Finally, we prove partially the conjecture given by n. Andruskiewitsch and H.-J. Schneider in the case of finite-dimensional pointed semilattice graded weak Hopf algebra H when grH is self-dual.

关键词： weak Hopf algebra self-duality weak Hopf quiver

Thermally Radiative Rotating Magneto-nanofluid Flow over an Exponential Sheet with Heat Generation and Viscous Dissipation:A Comparative Study

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Communications in Theoretical Physics 2018年第3期69卷 317-328页

作者： M.Sagheer M.Bilal S.Hussain R.n.ahmed Department of Mathematics Capital University of Science and Technology

This article examines a mathematical model to analyze the rotating flow of three-dimensional water based nanofluid over a convectively heated exponentially stretching sheet in the presence of transverse magnetic field with additional effects of thermal radiation,Joule heating and viscous ***(Ag),copper(Cu),copper oxide(Cu O),aluminum oxide(Al_2O_3)and titanium dioxide(Ti O_2)have been taken under consideration as the nanoparticles and water(H_2O)as the base *** suitable similarity transformations,the governing partial differential equations(PDEs)of the modeled problem are transformed to the ordinary differential equations(ODEs).These ODEs are then solved numerically by applying the shooting *** the particular situation,the results are compared with the available *** effects of different nanoparticles on the temperature distribution are also discussed graphically and *** is witnessed that the skin friction coefficient is maximum for silver based ***,the velocity profile is found to diminish for the increasing values of the magnetic parameter.

关键词： magnetohydrodynamics nanofluid viscous dissipation thermal radiation rotating flow

Rotational flow of Oldroyd-B nanofluid subject to Cattaneo-Christov double diffusion theory

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Applied Mathematics and Mechanics(English Edition) 2020年第7期41卷 1083-1094页

作者： A.HAFEEZ M.kHAn A.ahmed J.ahmed Department of Mathematics Quaid-i-Azam UniversityIslamabad 44000Pakistan Department of Basic Sciences University of Engineering and TechnologyTaxila 47050Pakistan

A nanofluid is composed of a base fluid component and nanoparticles, in which the nanoparticles are dispersed in the base fluid. The addition of nanoparticles into a base fluid can remarkably improve the thermal conductivity of the nanofluid, and such an increment of thermal conductivity can play an important role in improving the heat transfer rate of the base fluid. Further, the dynamics of non-newtonian fluids along with nanoparticles is quite interesting with numerous industrial applications. The present predominately predictive modeling studies the flow of the viscoelastic Oldroyd-B fluid over a rotating disk in the presence of nanoparticles. A progressive amendment in the heat and concentration equations is made by exploiting the Cattaneo-Christov heat and mass flux expressions. The characteristic of the Lorentz force due to the magnetic field applied normal to the disk is studied. The Buongiorno model together with the Cattaneo-Christov theory is implemented in the Oldroyd-B nanofluid flow to investigate the heat and mass transport mechanism. This theory predicts the characteristics of the fluid thermal and solutal relaxation time on the boundary layer flow. The von k′arm′an similarity functions are utilized to convert the partial differential equations(PDEs) into ordinary differential equations(ODEs). A homotopic approach for obtaining the analytical solutions to the governing nonlinear problem is carried out. The graphical results are obtained for the velocity field, temperature, and concentration distributions. Comparisons are made for a limiting case between the numerical and analytical solutions, and the results are found in good agreement. The results reveal that the thermal and solutal relaxation time parameters diminish the temperature and concentration distributions, respectively. The axial flow decreases in the downward direction for higher values of the retardation time parameter. The impact of the thermophoresis parameter boosts the temperature di

关键词： Oldroyd-B nanofluid rotating disk magnetohydrodynamic(MHD) Cattaneo-Christov theory analytical solution

Von kármán rotating flow of Maxwell nanofluids featuring the Cattaneo-Christov theory with a Buongiorno model

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Applied Mathematics and Mechanics(English Edition) 2020年第8期41卷 1195-1208页

作者： A.ahmed M.kHAn J.ahmed A.HAFEEZ Department of Mathematics Quaid-i-Azam UniversityIslamabad 44000Pakistan Department of Basic Sciences University of Engineering and TechnologyTaxila 47050Pakistan

This research paper analyzes the transport of thermal and solutal energy in the Maxwell nanofluid flow induced above the disk which is rotating with a constant angular *** significant features of thermal and solutal relaxation times of fluids are studied with a Cattaneo-Christov double diffusion theory rather than the classical Fourier’s and Fick’s laws.A novel idea of a Buongiorno nanofluid model together with the Cattaneo-Christov theory is introduced for the first time for the Maxwell fluid flow over a rotating ***,the thermal and solutal distributions are controlled with the impacts of heat source and chemical *** classical von karman similarities are used to acquire the non-linear system of ordinary differential equations(ODEs).The analytical series solution to the governing ODEs is obtained with the well-known homotopy analysis method(HAM).The validation of results is provided with the published results by the comparison *** graphically presented outcomes for the physical problem reveal that the higher values of the stretching strength parameter enhance the radial velocity and decline the circumferential *** increasing trend is noted for the axial velocity profile in the downward direction with the higher values of the stretching strength *** higher values of the relaxation time parameters in the Cattaneo-Christov theory decrease the thermal and solutal energy transport in the flow of Maxwell *** higher rate of the heat transport is observed in the case of a larger thermophoretic force.

关键词： Maxwell fluid nanoparticle Cattaneo-Christov theory rotating disk homotopy analysis method(HAM)

Evaluation of Hepatic Fibrosis and Hepatic Steatosis by Pulse Elastography (FIBROSCAn/CAP) in Asymptomatic Patients about 170 Cases at the Donka CHU national Hospital in Conakry

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Open Journal of Gastroenterology 2024年第4期14卷 125-138页

作者： Mamadou Sarifou Diallo Oumarou Youssouf Abdoulatif Yaogo Djenabou Diallo kadiatou Diallo Thierno Amadou Wann ahmed Tidiane Diallo Mamadou Lamine Yaya Bah Mamdou Diakhaby Mamadou Aliou kanté Djibril Sylla Department of Hepato-Gastroenterology The Donka National Hospital Conakry Guinea Faculty of Health Sciences and Techniques Gamal Abdel Nasser University Conakry Guinea Internal Medicine Department Centre Hospitalier Universitaire Communautaire de Bangui Bangui Central African Republic Department of Hepato Gastroenterology Angr&#233 University Hospital Abidjan Ivory Coast Department of Internal Medicine Donka National Hospital Conakry Guinea

Introduction: Fibroscan is a recent, non-invasive and non-irradiating diagnostic method. It is based on the principle of ultrasound, which enables liver tissue elasticity to be quantified using a probe, and fibrosis to be assessed. Fibroscan measures both elasticity correlated with hepatic fibrosis and CAP correlated with steatosis. The aim of this study was to evaluate hepatic fibrosis and steatosis using pulse elastometry (Fibroscan/CAP). Methods: This was a descriptive and analytical cross-sectional study in which 170 patients were included. It was conducted from October 1 2021 to December 31 2023, i.e. 27 months, in an outpatient clinic in the hepato-gastroenterology department of the Donka national hospital of the CHU Conakry. Results: Of the 170 patients identified, 87 were male (51%) and 83 female (49%), giving a M/F sex ratio of 1.04. The average age of our patients was 40. The 30 - 50 age group was the most affected, with a frequency of 58.23% (n = 99), followed by the 50 age group with a frequency of 29.41% (n = 50). Hepatomegaly, steatotic liver on ultrasonography, transaminase elevation and obesity were the main indications, respectively: (21.76%), (17.65%), (14.71%), and (13.53%). The examinations were requested by hepatogastroenterologists (47.06%), diabetologists (35.88%) and general practitioners (29%). Of the 170 patients, 100 patients (58.82%) had no significant fibrosis F0F1, 39 (22.94%) had moderate fibrosis F2, 20 patients (11.76%) had severe fibrosis F3 and 11 patients (6.47%) had fibrosis F4. Hepatic steatosis: 62 patients (36.47%) had no S0 steatosis;29.41% had S1 steatosis, 20% had S2 steatosis and 24 patients (14.11%) had S3 steatosis. Abdominal ultrasound revealed a normal liver in 67.05% of patients, hepatic steatosis in 29.41% and non-decompensated cirrhosis in 6 cases. Thus, 108 patients had the parameters required to calculate the Fatty Liver Index (FLI), steatosis was present in 20% of our patients, while 29.41% had an undetermined st

关键词： Cirrhosis Fibrosis Fibroscan/CAP non-Alcoholic Hepatic Steatosis Steatosis CHU Conakry

Etchability of Latent Fission Fragment Tracks in CR-39

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Chinese Physics Letters 2007年第11期24卷 3107-3110页

作者： Mukhtar ahmed Rana Physics Division Directorate of Science PINSTECH P.O. Nilore Islamabad Pakistan

We report the chemical etching behaviour of the CR-39 polymer detector exposed to fission fragments of 252Cf describing etchability of latent tracks, which are like nanocylinders. The fission fragment exposed detectors were etched in 1-7 n naOH water solutions at temperatures 50-80℃ for 45 min in the case of track length and 180 min in the case of track diameter measurements. The reduced etch rate S （called here etchability） is determined using experimental results for all etching conditions and the etching conditions with the highest reduced etch are obtained. Physics and energetics of bulk and track etching are discussed. Possible effects causing spurious changes in determination of activation energy of etching are investigated.

关键词： coated conductor buffer layer self-epitaxy CeO2