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Chinese Journal of Chemical Engineering 2018年第9期26卷 1904-1911页

作者： Anis H.Fakeeha ahmed s.Al-Fatesh Biswajit Chowdhury ahmed A.Ibrahim Wasim U.Khan shahid Hassan Kasim sasudeen ahmed Elhag Abasaeed Chemical Engineering Department College of Engineering King Saud University Department of Applied Chemistry Indian School of Mines

Methane decomposition reaction has been studied at three different activation temperatures（500℃,800℃ and950℃）over mesoporous alumina supported Ni–Fe and Mn–Fe based bimetallic *** co-impregnation of Ni on Fe/Al2O3the activity of the catalyst was retained even at the high activation temperature at 950℃ and up to180 *** Ni promotion enhanced the reducibility of Fe/Al2O3oxides showing higher catalytic activity with a hydrogen yield of 69%.The reactivity of bimetallic Mn and Fe over Al2O3catalyst decreased at 800℃ and 950℃ activation *** studies revealed that the catalyst could be effectively recycled up to *** addition of O2（1 ml,2 ml,4 ml）in the feed enhanced substantially CH4conversion,the yield of hydrogen and the stability of the catalyst.

关键词： Carbon nanotube Hydrogen production Methane decomposition Manganese promoter Nickel promoter

Effect of Metal Contact and Rapid Thermal Annealing on Electrical Characteristics of Graphene Matrix

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Chinese Physics Letters 2017年第10期34卷 65-69页

作者： s, Fahad M. Ali s. ahmed s. Khan s. Alam s. Akhtar Advanced Electronics Laboratories International Islamic University Islamabad Pakistan Department of Physics Federal Urdu University of Arts Sciences & Technology Karachi Pakistan

Development of graphene field effect transistors （GFETs） faces a serious challenge of graphene interface to the dielectric material. A single layer of intrinsic graphene has an average sheet resistance of the order of 1-5 kΩ/□. The intrinsic nature of graphene leads to higher contact resistance yielding into the outstanding properties of the material. We design a graphene matrix with minimized sheet resistance of 0.185 kΩ/□ with Ag contacts. The developed matrices on silicon substrates provide a variety of transistor design options for subsequent fabrication. The graphene layer is developed over 400 nm nickel in such a way as to analyze hypersensitive electrical properties of the interface for exfoliation. This work identifies potential of the design in the applicability of few-layer GFETs with less process steps with the help of analyzing the effect of metal contact and post-process anneMing on its electrical fabrication.

关键词： Effect of Metal Contact and Rapid Thermal Annealing on Electrical Characteristics of Graphene Matrix

spectrophotometric Determination of Albendazole Drug in Tablets： spectroscopic Characterization of the Chargetransfer solid Complexes

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Chinese Journal of Chemistry 2011年第2期29卷 324-332页

作者： Refat Moamen s Mohamed Gehad G. Fathi ahmed Department of Chemistry Faculty of Science Port Said University Port Said Egypt Department of Chemistry Faculty of Science Taif University 888 Taif Kingdom Saudi Arabia Chemistry Department Faculty of Science Cairo University Egypt

simple, rapid and reliable method for the determination of albendazole （ABZ） was described. This includes the utility of some π-acceptors such as 2,3-dichloro-5,6-dicyano-p-benzoquinone （DDQ） and 3,6-dichloro-2,5-dihydroxy-p-benzoquinone （p-CLA） for estimation of ABZ drug （act as donor）. The experimental conditions were optimized and the system obeys Beer＇s law for 7.50-80 and 10.00-85.00 ug·mL-1 of ABZ using DDQ and p-CLA, respectively. The molar absorptivity and sandell sensitivity were calculated to be 1.83× 10^3 and 1.12× 10^3 L·mol ·cm -1 and 2.60 and 3.40 ng·cm -2 using DDQ and p-CLA, respectively. The limits of detection and quantification were calculated to be （7.42 and 6.73） and （9.94 and 4.13） ug·mL-1 using DDQ and p-CLA, respectively. The proposed methods were successfully applied to the determination of ABZ in commercially available dosage forms. The reliability of the assays was established by parallel determination by the official method and recovery studies. The chemical structures of the solid charge-transfer （CT） complexes formed via reaction between ABZ under study and π-acceptors, have been elucidated using elemental analyses （C, H and N）, IR, 1H NMR and mass spectra.

关键词： albendazole DDQ p-CLA spectrophotometry charge-transfer complexes

structural,electronic,and magnetic properties of Co-doped ZnO

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Chinese Physics B 2012年第9期21卷 414-421页

作者： Bakhtiar Ul Haq A. Afaq R. ahmed s. Naseem Center of Excellence in solid state Physics University of the Punjab Quid-e-Azam CampusLahore-54590 Pakistan Department of Physics Faculty of Science Universiti Teknologi Malaysia Skudai Johar Malaysia Center of Excellence in solid state Physics University of the Punjab Quid-e-Azam Campus Lahore-54590 Pakistan

Density functional theory based calculations have been carried out to study structural, electronic, and magnetic properties of Znl-xCoxO （x = 0, 0.25, 0.50, 0.75） in the zinc-blende phase, and the generalized gradient approximation proposed by Wu and Cohen has been used. Our calculated lattice constants decrease while the bulk moduli increase with the increase of Co2＋ concentration. The calculated spin polarized band structures show the metallic behavior of Co-doped ZnO for both the up and the down spin cases with various doping concentrations. Moreover, the electron population is found to shift from the Zn-O bond to the Co-O bond with the increase of Co2~ concentration. The total magnetic moment~ the interstitial magnetic moment, the valence and the conduction band edge spin splitting energies, and the exchange constants decrease, while the local magnetic moments of Zn, Co, O, the exchange spin splitting energies, and crystal field splitting energies increase with the increase of dopant concentration.

关键词： density functional theory magnetic semiconductors generalized gradient approximation

synthesis of ZnO Nanoparticles onto sepiolite Needles and Determination of Their sensitivity toward Humidity, NO_2 and H_2

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Journal of Materials science & Technology 2016年第6期32卷 573-582页

作者： M.Hassan ahmed s.Afify J.M.Tulliani Department of Applied science and Technology Politecnico di Torino

This work investigated the sensitivity toward humidity, NO2 and H2 of ZnO modified sepiolite （si12Mg8O30（OH）4.（H2O）4.8H2O）. To this aim, sepiolite powder was first modified by leaching magnesium ions in HCI then by precipitating nano-sized Zn-based compounds under basic conditions. A subse- quent thermal treatment at 550 ℃ for 1 h was performed. The powders were characterized by X-ray diffraction （XRD）, specific surface area measurements, thermogravimetric and differential thermal anal- ysis and field emission scanning electron microscopy, as well as high resolution transmission electron microscopy. The XRD patterns showed that all leached heat treated samples were made of anhydrous sepiolite and of ZnO. sensors were then obtained by screen printing these materials onto commercial alumina substrates with Pt electrodes. All the investigated compositions were capable of detecting NO2 down to ppm level and 20 ppm H2, at an optimal working temperature of 300°C. These detection limits are in line with the current best results reported in literature.

关键词： Clay minerals Gas sensor sensitivity Hydrogen sensor Nitrogen Oxide

Design principle of s-scheme heterojunction photocatalyst

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Journal of Materials science & Technology 2022年第29期124卷 171-173页

作者： Quanlong Xu s.Wageh ahmed A.Al-Ghamdi Xin Li Key laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou325027China Department of Physics Faculty of ScienceKing Abdulaziz UniversityJeddah21589Saudi Arabia Institute of Biomass Engineering Key Laboratory of Energy Plants Resource and UtilizationMinistry of Agriculture and Rural AffairsSouth China Agricultural UniversityGuangzhou510642China

Recently,a new opinion was put forward on general design standards for s-scheme heterojunction *** types of s-scheme heterojunctions were ***,the critical understanding on the curved Fermi level at the interface of s-... 详细信息

关键词： s-scheme heterojunction p-type semiconductor n-type semiconductor Curved Fermi level

Impact Assessment and Mitigation Techniques for High Penetration Levels of Renewable Energy sources in Distribution Networks:Voltage-control Perspective

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Journal of Modern Power systems and Clean Energy 2022年第2期10卷 450-458页

作者： ahmed s.A.Awad Dave Turcotte Tarek H.M.El-Fouly Natural Resources Canada Can-metENERGYVarennesCanadaon leave from the Electrical Power and Machines DepartmentFaculty of EngineeringAin Shams UniversityCairo 11566Egyp Natural Resources Canada CanmetENERGYVarennesCanada Advanced Power and Energy Center Khalifa UniversityAbu DhabiUnited Arab Emirates

The integration of renewable distributed generation(RDG)into distribution networks is promising and increasing ***,high penetration levels of distributed generation(DG)are often limited as they may have an adverse effect on the operation of distribution *** of the operation challenges is the interaction between DG and voltage-control equipment,e.g.,an under-load tap changer(ULTC),which is basically designed to compensate for voltage changes caused by slow load *** integration of variable DGs leads to rapid voltage fluctuations,which can negatively affect the tap operation of *** paper investigates the impact of high penetration levels of RDG on the tap operation of ULTC in distribution networks through *** mitigation techniques that can alleviate this impact are also *** these techniques,constant power-factor mode is regarded as the best trade-off between the simplicity and effectiveness of minimizing the number of tap *** are performed on a Canadian benchmark rural distribution feeder using OpenDss software.

关键词： Renewable energy distributed generation(DG) voltage regulator load tap changer distribution network.

Enhanced Metaheuristics with Machine Learning Enabled Cyberattack Detection Model

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Intelligent Automation & soft Computing 2023年第9期37卷 2849-2863页

作者： ahmed s.Almasoud Department of Information systems College of Computer and Information SciencesPrince Sultan UniversityRiyadh12435Saudi Arabia

The Internet of Things(IoT)is considered the next-gen connection network and is ubiquitous since it is based on the *** Detection system(IDs)determines the intrusion performance of terminal equipment and IoT communication procedures from IoT environments after taking equivalent defence measures based on the identified *** this back-ground,the current study develops an Enhanced Metaheuristics with Machine Learning enabled Cyberattack Detection and Classification(EMML-CADC)model in an IoT *** aim of the presented EMML-CADC model is to detect cyberattacks in IoT environments with enhanced *** attain this,the EMML-CADC model primarily employs a data preprocessing stage to normalize the data into a uniform *** addition,Enhanced Cat swarm Optimization based Feature selection(ECsO-Fs)approach is followed to choose the optimal feature ***,Mayfly Optimization(MFO)with Twin support Vector Machine(TsVM),called the MFO-TsVM model,is utilized for the detection and classification of ***,the MFO model has been exploited to fine-tune the TsVM variables for enhanced *** performance of the proposed EMML-CADC model was validated using a benchmark dataset,and the results were inspected under several *** comparative study concluded that the EMML-CADC model is superior to other models under different measures.

关键词： Metaheuristics cyberattack detection machine learning cat swarm optimization security

Deep Learning with Image Classification Based secure CPs for Healthcare sector

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Computers, Materials & Continua 2022年第8期72卷 2633-2648页

作者： ahmed s.Almasoud Abdelzahir Abdelmaboud Faisal s.Alsubaei Manar ahmed Hamza Ishfaq Yaseen Mohammed Abaker Abdelwahed Motwakel Mohammed Rizwanullah Department of Information systems College of Computer and Information SciencesPrince Sultan UniversityRiyadh12435Saudi Arabia Department of Information systems College of Science and ArtsKing Khalid UniversityMahayil Asir62529Saudi Arabia Department of Cybersecurity College of Computer Science and EngineeringUniversity of JeddahJeddah21959Saudi Arabia Department of Computer and self Development Preparatory Year DeanshipPrince Sattam bin Abdulaziz UniversityAlKharj16278Saudi Arabia Department of Computer science Community CollegeKing Khalid UniversityMahayil Asir62529Saudi Arabia

Cyber-Physical system(CPs)involves the combination of physical processes with computation and communication *** recent advancementsmade in cloud computing,Wireless sensor Network(WsN),healthcare sensors,*** to develop CPs as a proficient model for healthcare applications especially,home patient *** several techniques have been proposed earlier related to CPs structures,only a handful of studies has focused on the design of CPs models for health care ***,the proposal for a dedicated CPs model for healthcare sector necessitates a significant interest to ensure data *** overcome the challenges,the current research paper designs a Deep Learning-based Intrusion Detection and Image Classification for secure CPs(DLIDIC-sCPs)model for healthcare *** aim of the proposed DLIDIC-sCPs model is to achieve secure image transmission and image classification process for CPs in healthcare ***,data acquisition takes place with the help of sensors and detection of intrusions is performed using Fuzzy Deep Neural Network(FDNN)***,Multiple share Creation(MsC)approach is used to create several shares of medical image so as to accomplish ***,blockchain is employed as a distributed data storage entity to create a ledger that provides access to the *** image classification,Inception v3 with Fuzzy Wavelet Neural Network(FWNN)is utilized that diagnose the disease from the applied medical ***,salp swarm Algorithm(ssA)is utilized to fine tune the parameters involved in WNN model,thereby boosting its classification performance.A wide range of simulations was carried out to highlight the superiority of the proposed DLIDIC-sCPs *** simulation outcomes confirm that DLIDIC-sCPs approach demonstrates promising results in terms of security,privacy,and image classification outcomes over recent state-of-the-art techniques.

关键词： Cyber Physical systems healthcare cybersecurity deep learning share creation image classification

Experimental and mathematical modeling of Cr(Ⅵ) removal using nano-magnetic Fe3O4-coated perlite from the liquid phase

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Chinese Journal of Chemical Engineering 2020年第6期28卷 1582-1590页

作者： Ismail M.ahmed Mostafa M.Hamed sayed s.Metwally Chemistry Department College of ScienceJouf UniversitySkakaSaudi Arabia Hot Laboratories and Waste Management Center Atomic Energy Authority13759 CairoEgypt

Modification of perlite using nano-magnetic iron oxide was implemented to produce nano-magneticFe3O4-coated perlite composite(Fe3O4/Perlite).The prepared composite was characterized using scanning Electron Microscopy,Fourier-Transform Infrared spectroscopy and Powder X-ray *** potentiality of both perlite and Fe3O4/Perlite composite to eliminate Cr(VI)from the environmentally relevant water was *** influence of main factors which could affect the adsorption was studied including;pH of medium,shaking time and Cr(VI)ions *** experimental outcome demonstrated that the modification of perlite by nano-magnetic Fe3O4 showed a significantly enhanced Cr(VI)removal efficiency relative to that of unmodified *** the kinetic studies,the experimental data fitted well with the pseudo-second-order ***,it proposes that Langmuir isotherm is more adequate than the Freundlich isotherm for both perlite and modified *** results recommended that Fe3O4/Perlite composite had a great potential as an economic and efficient adsorbent of Cr(VI)from contaminated water,which has huge application potential.

关键词： Nano-magnetic Composite Kinetics Isotherm Perlite Adsorption