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Simulation of a molten salt fast reactor using the COmSOL multiphysics software

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Nuclear Science and Techniques 2020年第12期31卷 1-19页

作者： D.H.Daher m.Kotb a.m.khalaf moustafa S.El-Koliel Abdelfattah Y.Soliman Department of Physics Faculty of ScienceAl-Azhar UniversityCairoEgypt Department of Reactors Nuclear Research CenterAtomic Energy AuthorityCairoEgypt Nuclear Engineering Department King Abdulaziz UniversityJeddahSaudi Arabia

In this study,COmSOL v5.2 multiphysics software was utilized to perform coupled neutronics and thermal–hydraulics simulations of a molten salt fast reactor,and the SCALE v6.1 code package was utilized to generate the homogenized cross-section data *** library’s 238 cross-section groups were categorized into nine groups for the simulations in this *** results of the COmSOL model under no fuel flow conditions were verified using the SCALE v6.1 code results,and the results of the neutronics and thermal–hydraulics simulations were compared to the results of previously published *** results indicated that the COmSOL model that includes the cross-section library generated by the SCALE v6.1 code package is suitable for the steady-state analysis and design assessment of molten salt fast ***,this model was utilized to investigate the neutronics and thermal–hydraulics behaviors of the *** designs were simulated and analyzed in this model,and the results indicated that even if the wall of the core is curved,hot spots occur in the upper and lower portions of the core’s center near the reflectors.A new design was proposed that utilizes a flow rate distribution system,and the simulation results of this design showed that the maximum temperature in the core was approximately 1032 K and no hot spots occurred.

关键词： molten salt COmSOL SCALE Neutronics Thermal-hydraulic

Vibrational, rotational, and triaxiality features in extended O(6) dynamical symmetry of IBm using three-body interactions

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Nuclear Science and Techniques 2020年第5期31卷 44-56页

作者： a.m.khalaf Azza O.El-Shal m.m.Taha m.A.El-Sayed Physics Department Faculty of ScienceAl-Azhar UniversityCairoEgypt mathematics and Theoretical Physics Department Nuclear Research CenterAtomic Energy AuthorityCairo 13759Egypt

The shape transition between the vibrational U(5)and deformed c-unstable O(6)dynamical symmetries of sd interacting boson model has been investigated by considering a modified O(6)Hamiltonian,providing that the coefficients of the Casimir operator of O(5)are N-dependent,where N is the total number of *** modified O(6)Hamiltonian does not contain the number operator of the d boson,which is responsible for the vibrational *** addition,the deformation features can be achieved without using the SU(3)limit by adding to the O(6)dynamical symmetry the three-body interaction[QQQ]^(0),where Q is the O(6)symmetric quadrupole ***,triaxiality can be generated through the inclusion of the cubic d-boson interaction[d+d+d+]^(3)·∣ddd∣^(3).The classical limit of the potential energy surface(PES),which represents the expected value of the total Hamiltonian in a coherent state,is studied and *** modified O(6)model is applied to the even–even^124-132 Xe *** parameters for the Hamiltonian and the PESs are calculated using a simulated search program to obtain the minimum root mean square deviation between the calculated and experimental excitation energies and B(E2)values for a number of low-lying levels.A good agreement between the calculations and experiment results is found.

关键词： Nuclear structure Extended O(6)of IBm Three-body interactions Coherent state

multicomponent synthesis and designing of tetrasubstituted imidazole compounds catalyzed via ionic-liquid for acid steel corrosion protection:Experimental exploration and theoretical calculations

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Chinese Journal of Chemical Engineering 2023年第3期55卷 304-319页

作者： Hany m.Abd El-Lateef mai m.khalaf K.Shalabi Antar A.Abdelhamid Department of Chemistry College of ScienceKing Faisal UniversityAl-Ahsa 31982Saudi Arabia Department of Chemistry Faculty of ScienceSohag UniversitySohag 82524Egypt Chemistry Department Faculty of ScienceMansoura UniversityMansouraEgypt Chemistry Department Faculty of ScienceAlbaha UniversityAlbaha 1988Saudi Arabia

Five new tetrasubstituted imidazoles were designed with outstanding yields(83%-92%) in the occurrence of ionic liquid-based-pyridinium as a catalyst. The constructions of all synthesized derivatives were established by spectral tools and their purities were verified using thin-layer chromatography(TLC), displaying single-spot. The performance of corrosion protection of the prepared imidazole derivatives was examined theoretically and practically for acid steel corrosion. The experimental study was conducted by electrochemical(electrochemical impedance spectroscopy(EIS) and Tafel polarization(PPS)) *** findings from the used approaches concluded that the synthesized compounds were wellorganized inhibitors with an efficiency of 90.7%-98.5% at 50℃ and 0.7 mmol·L^(-1). The Tafel polarization results indicate the protective action of the additives was under mixed-monitoring. The additive adsorption on the electrode interface performed as a distinguished aspect for protection. The surface exploration on the blank and protected metal was completed by field emission scanning electron microscopy(FESEm). Computational studies by monte Carlo(mC) simulation and quantum chemical calculation(DFT)were related to practical findings. The corrosion protection adsorption mechanism was reinforced by the preferable fitted Langmuir isotherm model. All findings from the applied-inspected approaches alternately confirm each other.

关键词： Adsorption Ionic-liquid catalyst Tetrasubstituted imidazoles Corrosion Pickling acid mathematical modeling

A new nonlinear oscillator with infinite number of coexisting hidden and self-excited attractors

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Chinese Physics B 2018年第4期27卷 208-213页

作者： Yan-Xia Tang Abdul Jalil m khalaf Karthikeyan Rajagopal Viet-Thanh Pham Sajad Jafari Ye Tian College of Science Hebei North University Zhangjiakou 075000 China Engineering Technology Research Center of Population Health lnformatization in Hebei Province Zhangjiakou 075000 China Department of mathematics Faculty of Computer Science and Mathematics University of Kufa Najaf Iraq Department of Electrical and Communication Engineering the PNG University of Technology Lae Centre for Nonlinear Dynamics Defense University Ethiopia modeling Evolutionary Algorithms Simulation and Artificial Intelligence Faculty of Electrical & Electronics Engineering Ton Duc Thang University Ho Chi Mirth City Vietnam Biomedical Engineering Department Amirkabir University of Technology Tehran 15875-4413 Iran

In this paper,we introduce a new two-dimensional nonlinear oscillator with an infinite number of coexisting limit *** limit cycles form a layer-by-layer structure which is very *** percent of these limit cycles are self-excited attractors while sixty percent of them are hidden *** this new system to its forced version,we introduce a new chaotic system with an infinite number of coexisting strange *** implement this system through field programmable gate arrays.

关键词： chaotic oscillators multistability hidden attractors

Isotherm and kinetic studies on the adsorption of humic acid molecular size fractions onto clay minerals

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Acta Geochimica 2019年第6期38卷 863-871页

作者： mohamed E.A.El-Sayed moustafa m.R.khalaf James A.Rice Department of Chemistry and Biochemistry South Dakota State UniversityBrookingsSD 57007USA Soils Waterand Environmental Research InstituteAgriculture Research CenterEl-GizaEgypt Chemistry Department Faculty of ScienceMinia UniversityEl-Minia 61519Egypt

Humic acid(HA)can adsorb onto mineral surfaces,modifying the physicochemical properties of the ***,understanding the sorption behavior of HA onto mineral surfaces is of particular interest,since the fate and transport of many organic and inorganic contaminants are highly correlated to HA adsorbed onto clay *** to the extreme heterogeneity of HA,the extracted IHSS Leonardite humic acid(LHA)used in this work was fractionated using an ultrafiltration technique(UF)into different molecular size fractions(Fr1,>0.2μm;Fr2,0.2 pm-300,000 daltons;Fr3,300,000-50,000 daltons;Fr4,50,000-10,000 daltons;Fr5,10,000-1000 daltons).Equilibrium and the kinetics of LHA and fraction adsorption onto kaolinite and montmorillonite were *** results demonstrated that the maximum adsorption capacity of LHA,Frl,Fr2,Fr3,Fr4,and Fr5 was 5.99,13.69,10.29,7.02,5.9&and 5.09 on kaolinite while it was 8.29,22.62,13.17,8.91,8.62,and 5.69 on montmorillonite,*** adsorption equilibrium data showed that the adsorption behavior of LHA and its fractions could be described more practically by the Langmuir model than the Freundlich *** rate of humic acid fraction adsorption onto clays increased with decreasing molecular size fraction and increasing carboxylic group ***-first-and second-order models were used to assess the kinetic data and the rate *** results explained that LHA and its fractions adsorption on clay minerals conformed more to pseudosecondo rder.

关键词： Kaolinite montmorillonite Leonardite humic acid Humic acid fractions Kinetics Equilibrium

Bifurcation phenomena and control for magnetohydrodynamic flows in a smooth expanded channel

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Chinese Physics B 2014年第11期23卷 374-383页

作者： G.C.Layek mani Shankar mandal H.A.khalaf Department of mathematics The University of Burdwan Department of mathematics Krishnagar Govt. College KrishnagarNadia 741101India Thi-Qar University Marshes Research Center Thi-QarIraq

This work reports the effects of magnetic field on an electrically conducting fluid with low electrical conductivity flowing in a smooth expanded channel. The governing nonlinear magnetohydrodynamic （mHD） equations in induction- free situations are derived in the framework of mHD approximations and solved numerically using the finite-difference technique. The critical values of Reynolds number （based on upstream mean velocity and channel height） for symmetry breaking bifurcation for a sudden expansion channel （1：4） is about 36, whereas the value in the case of the smooth expansion geometry used in this work is obtained as 298, approximately （non-magnetic case）. The flow of an electrically conducting fluid in the presence of an externally applied constant magnetic field perpendicular to the plane of the flow is reduced significantly depending on the magnetic parameter （m）. It is expansion （1：4） is about 475 for the magnetic parameter m found that the critical value of Reynolds number for smooth = 2. The separating regions developed behind the smooth symmetric expansion are decreased in length for increasing values of the magnetic parameter. The bifurcation diagram is shown for a symmetric smoothly expanding channel. It is noted that the critical values of Reynolds number increase with increasing magnetic field strength.

关键词： weakly electrically conducting fluid flow bifurcation asymmetric flow smooth expansion

Efficient Resource Allocation in Fog Computing Using QTCS model

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Computers, materials & Continua 2022年第2期70卷 2225-2239页

作者： m.Iyapparaja Naif khalaf Alshammari m.Sathish Kumar S.Siva Rama Krishnan Chiranji Lal Chowdhary School of Information Technology and Engineering Vellore Institute of TechnologyVellore632014India mechanical Engineering University of HailSaudi Arabia

Infrastructure of fog is a complex system due to the large number of heterogeneous resources that need to be *** embedded devices deployed with the Internet of Things(IoT)technology have increased since the past few years,and these devices generate huge amount of *** devices in IoT can be remotely connected and might be placed in different locations which add to the network *** time applications require high bandwidth with reduced latency to ensure Quality of Service(QoS).To achieve this,fog computing plays a vital role in processing the request locally with the nearest available resources by reduced *** of themajor issues to focus on in a fog service is managing and allocating *** theory is one of the most popular mechanisms for task *** this work,an efficient model is designed to improve QoS with the efficacy of resource allocation based on a Queuing Theory based Cuckoo Search(QTCS)model which will optimize the overall resource management process.

关键词： Queuing theory Cuckoo search QoS resource allocation energy efficiency

Performance Evaluation of Calcium Alkali-treated Oil Palm/Pineapple Fibre/Bio-phenolic Composites

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Journal of Bionic Engineering 2022年第5期19卷 1493-1503页

作者： Sameer A.Awad Hassan Fouad Eman m.khalaf N.Saba Hom N.Dhakal m.Jawaid Othman Y.Alothman Department of Chemistry School of Science and TechnologyUniversity of New EnglandArmidaleNSW 2351Australia Department of Chemistry College of Education for Pure ScienceUniversity of Al-AnbarRamadi 31001Iraq Biomedical Engineering Department Faculty of EngineeringHelwan UniversityHelwan 11792Egypt Pharmacy Department Al-Maarif University CollegeAnbar 3001 RamadiIraq Laboratory of Biocomposite Technology Institute of Tropical Forestry and Forest Products(INTROP)Universiti Putra Malaysia43400 SerdangMalaysia Advanced Polymers and Composites(APC)Research Group School of Mechanical and Design EngineeringUniversity of PortsmouthPortsmouth PO13DJUK Department of Chemical Engineering College of EngineeringKing Saud UniversityRiyadh 11433Saudi Arabia

The utilisation of oil palm fibre(OPF)and pineapple leaf fibres(PALF)as reinforcement materials for bio-phenolic composites is growing especially in automotive lightweight *** major aim of this current study is to investigate the influence of alkali(Ca(OH)_(2)) treatment on pure and hybrid *** effects of enhancements in chemical interactions were evaluated by the Fourier-Transform Infrared Spectrometer(FTIR).Dynamic mechanical Analysis(DmA)and Thermogravimetric Analysis(TGA)performance of untreated reinforcements(OPF and PALF)and treated(OPF/OPF)composites at varying temperature and noted sufficient interfacial bonding contributing towards the improvements in thermal *** DmA results,the storage modulus improved with treated composites while the damping factor was ***,the treated hybrid composites exhibited significant improvements in thermal stability compared to untreated fibre *** results indicated that alkali calcium hydroxide(Ca(OH2(:T)incorporation in hybrid composites(OPF/PALF)results in increased tensile strength and modulus among all ***,the alkali-treated(Ca(OH)_(2))-treated pure composite(T/50%PALF),and hybrid composites(T/1OPF.1PALF)exhibited better flexural strength as compared with other *** contrast,the T/50%PALF showed higher flexural stress of 78.2 mPa,while the flexural modulus was recorded at 6503 *** can be proposed from the findings of this study that the alkali treatment(5%Ca(OH)_(2))can be utilised to improve the strength and efficiency of agriculture biomass to be used as reinforcements in ***,the hybridisation of bio-fibre composites has the potential as a novel variety of biodegradable and sustainable composites appropriate for several industrial and engineering applications.

关键词： Hybrid fibre composites Alkali treatments Surface modifications mechanical properties Thermal stability

multi-Tier Sentiment Analysis of Social media Text Using Supervised machine Learning

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Computers, materials & Continua 2023年第3期74卷 5527-5543页

作者： Hameedur Rahman Junaid Tariq m.Ali masood Ahmad F.Subahi Osamah Ibrahim khalaf Youseef Alotaibi Department of Creative Technologies Air UniversityE-9 Islamabad44230Pakistan Department of Computer Science National University of Modern LanguagesRawalpindiPakistan Department of Computer Science University College of Al JamoumUmm Al-Qura UniversityMakkah21421Saudi Arabia Al-Nahrain Nano-Renewable Energy Research Center Al-Nahrain UniversityBaghdad10072Iraq Department of Computer Science College of Computer and Information SystemsUmm Al-Qura UniversityMakkah21955Saudi Arabia

Sentiment Analysis(SA)is often referred to as opinion *** is defined as the extraction,identification,or characterization of the sentiment from ***,the sentiment of a textual document is classified into binary classes i.e.,positive and ***,fine-grained classification provides a better insight into the *** downside is that fine-grained classification is more challenging as compared to *** the contrary,performance deteriorates significantly in the case of multi-class *** this study,pre-processing techniques and machine learning models for the multi-class classification of sentiments were *** augment the performance,a multi-layer classification model has been *** to similitude with social media text,the movie reviews dataset has been used for the *** machine learning models namely Decision Tree,Support Vector machine,and Naive Bayes models have been implemented for the task of sentiment *** have compared the models of single-layer architecture with multi-tier *** results of multi-tier model have slight improvement over the single-layer ***,multi-tier models have better recall which allow our proposed model to learn more *** have discussed certain shortcomings of the model that will help researchers to design multi-tier models with more contextual information.

关键词： Sentiment analysis machine learning multi-class classification svm decision tree naive bayes