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Wear properties of copper and copper composites powders consolidated by high-pressure torsion

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Friction 2020年第2期8卷 433-450页

作者： Mohamed ibrahim abd El AAL Mechanical Engineering Department College of EngineeringPrince Sattam Bin Abdulaziz UniversityWadi Addawaser 11991Saudi Arabia Mechanical Design&Production Department Faculty of EngineeringZagazig UniversityZagazig 44519Egypt

The wear characteristics of Cu and Cu-SiC composite microsize powders consolidated by cold compaction combined with sintering or high-pressure torsion(HPT)were *** HPT processed(HPTed)samples with bimodal and trimodal microstructures and fine Cu grains and SiC particle sizes have superior hardness,reasonable ductility level,and high wear *** wear mass loss and coefficient of friction of HPTed samples were remarkably lower than that of cold-compacted and sintered samples as well as that of micro and nano Cu and Cu-SiC composites from previous *** sample fabrication method has an apparent influence on the wear *** wear mechanism was converted from adhesive,delamination,three-body mechanism,grooves(take off the SiC particles),and cracks into abrasive wear after *** can be considered a dominant wear mechanism in all *** worn surface morphology and analysis support the relationship between wear mechanism and characteristics.

关键词： Cu-SiC composite powders high-pressure torsion(HPT) fine and coarse grains wear characteristics worn surface morphology

Ciprofloxacin adsorption from aqueous solution onto chemically prepared carbon from date palm leaflets

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Journal of Environmental Sciences 2012年第9期24卷 1579-1586页

作者： El-Said ibrahim El-Shafey Haider Al-Lawati asmaa Soliman Al-Sumri Department of Chemistry College of ScienceSultan Qaboos UniversityP.O.Box 36-Al-Khodh 123MuscatOman

A chemically prepared carbon was synthesized from date palm leaflets via sulphuric acid carbonization at 160℃. Adsorption of ciprofloxacin （CIP） from aqueous solution was investigated in terms of time, pH, concentration, temperature and adsorbent status （wet and dry）. The equilibrium time was found to be 48 hr. The adsorption rate was enhanced by raising the temperature for both adsorbents, with adsorption data fitting a pseudo second-order model well. The activation energy, Ea, was found to be 17 kJ/mol, indicating a diffusion-controlled, physical adsorption process. The maximum adsorption was found at initial pH 6. The wet adsorbent showed faster removal with higher uptake than the dry adsorbent, with increased performance as temperature increased （25--45℃）. The equilibrium data were found to fit the Langmuir model better than the Freundlich model. The thermodynamic parameters showed that the adsorption process is spontaneous and endothermic. The adsorption mechanism is mainly related to cation exchange and hydrogen bonding.

关键词： ciprofloxacin carbon adsorption palm leaflets

Tagetones A and B, new cytotoxic monocyclic diterpenoids from flowers of Tagetes minuta

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Chinese Journal of Natural Medicines 2017年第7期15卷 546-549页

作者： Sabrin Ragab Mohamed ibrahim Gamal abd Allah Mohamed Department of Pharmacognosy and Pharmaceutical Chemistry College of Pharmacy Taibah University Al-Madinah Al-Munawarah 30078 Saudi Arabia Department of Natural Products and Alternative Medicine Faculty of Pharmacy King Abdulaziz University Jeddah 21589 Saudi Arabia

Tagetones A(1) and B(2), two new monocyclic diterpenoids were isolated from the n-hexane fraction of fresh flowers of Tagetes minuta L.(Asteraceae). Their structures were established by multiple spectroscopic methods(IR, HR-ESI-MS, and 1D-, and 2D-NMR), in addition to comparison with literature data. Compound 1 showed cytotoxic activity towards MCF7 and A549 cancer cells with IC_(50) values being 4.68 and 4.24 μmol·L^(-1), respectively, compared to doxorubicin(IC_(50) 0.13 and 1.12 μmol·L^(-1), respectively). Compound 2 also exhibited significant activity against HCT116 cancer cells(IC_(50), 6.30 μmol·L^(-1)).

关键词： Tagetes minuta Asteraceae Monocyclic diterpenoids Tagetones Cytotoxic

Power frequency AC voltage measurement based on double wound Rogowski coil

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High Voltage 2017年第2期2卷 129-135页

作者： Mohamed E.ibrahim Amr M.abd-Elhady High Voltage and Dielectric Materials Lab. Faculty of EngineeringMenoufia UniversityShebin El_Kom 32511Egypt

This study presents a technique for power frequency AC voltage *** proposed technique utilises a capacitor having a low capacitance in addition to a double wound Rogowski *** technique depends on capacitor current measurement using the double wound Rogowski *** voltage across the capacitor that connected in parallel with the system at which AC voltage is intended to be measured is *** proposed technique is experimentally evaluated by designing the measurement system and using a digital signal processing board for the reconstruction ***,the experimental results based on Rogowski coil measurements are compared with those obtained from reference ***,the obtained results validate the efficacy of the proposed technique in power frequency AC voltage measurement.

关键词： Rogowski double capacitance

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

Mathematical Modeling and Evaluation of Reliability Parameters Based on Survival Possibilities under Uncertain Environment

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Computer Modeling in Engineering & Sciences 2023年第3期134卷 1943-1956页

作者： Alhanouf Alburaikan Hamiden abd El-Wahed Khalifa Pavan Kumar SeyedaliMirjalili ibrahim Mekawy Department of Mathematics College of Science and ArtsQassim UniversityAl-Badaya51951Saudi Arabia Department of Operations Research Faculty of Graduate Studies for Statistical ResearchCairo UniversityGiza12613Egypt Division of Mathematics School of Advanced Science and LanguagesVIT Bhopal UniversitySehore466114India Centre for Artificial Intelligence Research and Optimization Torrens University AustraliaBrisbane4006Australia Department of Mathematics College of Science and ArtsQassim UniversityAr Rass6688Saudi Arabia YFL(Yonsei Frontier Lab) Yonsei UniversitySeoul03722Korea

In this article,mathematical modeling for the evaluation of reliability is studied using two *** of the methods,is developed based on possibility *** performance of the reliability of the system is of prime *** view of this,the outcomes for the failure are required to evaluate with utmost *** possibility theory,the reliability information data determined from decision-making experts are *** samemethod is also related to the survival possibilities as against the survival *** other method is the one that is developed using the concept of approximation of closed interval including the piecewise quadratic fuzzy *** this method,a decision-making expert is not sure of his/her estimates of the reliability *** experiments are performed to illustrate the efficiency of the suggested methods in this *** the end,the paper is concluded with some future research directions to be explored for the proposed approach.

关键词： Reliability function probabilistic function piecewise quadratic fuzzy numbers survival possibility failure rate possibility distribution state function closed interval approximation

3D FEM simulations and experimental validation of plastic deformation of pure aluminum deformed by ECAP and combination of ECAP and direct extrusion

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Transactions of Nonferrous Metals Society of China 2017年第6期27卷 1338-1352页

作者： Mohamed ibrahim abd EL AAL Mechanical engineering Department College of Engineering Prince Sattam Bin Abdulaziz UniversityWadi Addawasir Kingdom of Saudi Arabia Mechanical Design & Production Department Faculty of Engineering Zagazig University Zagazig Egypt

Rigid-viscoplastic3D finite element simulations(3D FEM)of the equal channel angular pressing(ECAP),thecombination of ECAP+extrusion with different extrusion ratios,and direct extrusion of pure aluminum were performed ***3D FEM simulations were carried out to investigate the load-displacement behavior,the plastic deformationcharacteristics and the effective plastic strain homogeneity of Al-1080deformed by different forming *** simulationresults were validated by microstructure observations,microhardness distribution maps and the correlation between the effectiveplastic strain and the microhardness ***3D FEM simulations were performed successfully with a good agreement with theexperimental *** load-displacement curves and the peak load values of the3D FEM simulations and the experimentalresults were close from each *** microhardness distribution maps were in a good conformity with the effective plastic straincontours and verifying the3D FEM simulations *** ECAP workpiece has a higher degree of deformation homogeneity thanthe other deformation *** microhardness values were calculated based on the average effective plastic *** microhardness values fitted the experimental results *** microstructure observations in the longitudinal andtransverse directions support the3D FEM effective plastic strain and microhardness distributions result in different formingprocesses.

关键词： equal channel angular pressing (ECAP) extrusion finite element method (FEM) microhardness deformation homogeneity microstructure

Mathematical Morphology View of Topological Rough Sets and Its Applications

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Computers, Materials & Continua 2023年第3期74卷 6893-6908页

作者： ibrahim Noaman abd El Fattah El Atik Tamer Medhat Manal E.Ali Department of Mathematics Faculty of Science and Arts in Al-MandaqAl-Baha UniversityKingdom of Saudi Arabia Department of Mathematics Faculty of ScienceTanta UniversityTantaEgypt Department of Electrical Engineering Faculty of EngineeringKafrelsheikh UniversityKafrelsheikh33516Egypt Department of Physics and Engineering Mathematics Faculty of EngineeringKafrelsheikh UniversityKafrelsheikh33516Egypt

This article focuses on the relationship between mathematical morphology operations and rough sets,mainly based on the context of image retrieval and the basic image correspondence *** morphological procedures and set approximations in rough set theory have some clear *** initiatives have been made to connect rough sets with mathematical *** significant publications have been written in this *** attempt to show a direct connection between mathematical morphology and rough sets through relations,a pair of dual operations,and neighborhood *** sets are used to suggest a strategy to approximatemathematicalmorphology within the general paradigm of soft computing.A single framework is defined using a different technique that incorporates the key ideas of both rough sets and mathematical *** paper examines rough set theory from the viewpoint of mathematical morphology to derive rough forms of themorphological structures of dilation,erosion,opening,and *** newly defined structures are applied to develop algorithm for the differential analysis of chest X-ray images from a COVID-19 patient with acute pneumonia and a health *** algorithm and rough morphological operations show promise for the delineation of lung occlusion in COVID-19 patients from chest *** foundations of mathematical morphology are covered in this *** that,rough set theory ideas are taken into account,and their connections are ***,a suggested image retrieval application of the concepts from these two fields is provided.

关键词： Mathematical morphology rough set theory topological spaces COVID-19

Swarming Behavior of Harris Hawks Optimizer for Arabic Opinion Mining

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Computers, Materials & Continua 2021年第12期69卷 4129-4149页

作者： Diaa Salam abd Elminaam Nabil Neggaz ibrahim abdulatief Ahmed Ahmed El Sawy Abouelyazed Department of Information Systems Faculty of Computers and Artificial IntelligenceBenha University12311Egypt Department of Computer Science Faculty of Computer ScienceMisr International UniversityEgypt Universite des Sciences at de la Technologie d’Oran Mohamed Boudiaf USTO-MBBP 1505EL M’naouer31000 OranLaboratoire Signal Image Parole(SIMPA)Department d’informatiqueFaculte des Mathematiques et InformatiqueAlgerie Department of Computer Science Faculty of Computers and Artificial IntelligenceBenha University12311Egypt Department of Computer Science Obour High Institute for Computers and InformaticsEgypt

At present,the immense development of social networks allows generating a significant amount of textual data,which has facilitated researchers to explore the field of opinion *** addition,the processing of textual opinions based on the term frequency-inverse document frequency method gives rise to a dimensionality *** study aims to detect the nature of opinions in the Arabic language employing a swarm intelligence(SI)-based algorithm,Harris hawks algorithm,to select the most relevant *** experimental study has been tested on two datasets:Arabic Jordanian General Tweets and Opinion Corpus for *** terms of accuracy and number of features,the results are better than those of other SI based algorithms,such as grey wolf optimizer and grasshopper optimization algorithm,and other algorithms in the literature,such as differential evolution,genetic algorithm,particle swarm optimization,basic and enhanced whale optimizer algorithm,slap swarm algorithm,and ant–lion optimizer.

关键词： Arabic opinion mining Harris hawks optimizer feature selection AJGT and OCA datasets