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Journal of magnesium and Alloys 2024年第5期12卷 1931-1943页

作者： farid Bahari-Sambran Fernando Carreno C.m.Cepeda-Jiménez Alberto Orozco-Caballero Physical metallurgy Department CENIM-CSICAv.Gregorio del Amo 828040 MadridSpain Department of mechanical Engineering Chemistry and Industrial DesignPolytechnic University of MadridRonda de Valencia 328012MadridSpain

The aim of this work is to predict,for the first time,the high temperature flow stress dependency with the grain size and the underlaid deformation mechanism using two machine learning models,random forest(RF)and artificial neural network(ANN).With that purpose,a ZK30 magnesium alloy was friction stir processed(FSP)using three different severe conditions to obtain fine grain microstructures(with average grain sizes between 2 and 3μm)prone to extensive superplastic *** three friction stir processed samples clearly deformed by grain boundary sliding(GBS)deformation mechanism at high *** maximum elongations to failure,well over 400% at high strain rate of 10^(-2)s^(-1),were reached at 400℃ in the material with coarsest grain size of 2.8μm,and at 300℃ for the finest grain size of 2μ***,the superplastic response decreased at 350℃ and 400℃ due to thermal instabilities and grain coarsening,which makes it difficult to assess the operative deformation mechanism at such *** work highlights that the machine learning models considered,especially the ANN model with higher accuracy in predicting flow stress values,allow determining adequately the superplastic creep behavior including other possible grain size scenarios.

关键词： machine learning Artificial intelligence magnesium alloys Superplasticity Friction stir processing Grain coarsening

Thermal properties and high-temperature ablation of high-entropy (Ti_(0.25)V_(0.25)Zr_(0.25)Hf_(0.25))B_(2) coating on graphite substrate

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Journal of Advanced Ceramics 2024年第8期13卷 1268-1281页

作者： Ana C.Feltrin Daniel Hedman farid Akhtar Division of materials Science Lulea University of TechnologyLulea 97187Sweden Center for multidimensional Carbon materials(CmCm) Institute for Basic Science(IBS)Ulsan 44919Republic of Korea

An entropy-stabilized multicomponent ultrahigh-temperature ceramic(UHTC)coating,(Ti_(0.25)V_(0.25)Zr_(0.25)Hf_(0.25))B_(2),on a graphite substrate was in-situ sintered by spark plasma sintering(SPs)from constituent transition metal diboride ***(Ti_(0.25)V_(0.25)Zr_(0.25)Hf_(0.25))B_(2) coating had a hardness of 31.2±2.1 GPa and resisted 36.9 GPa of stress before delamination,as observed at the *** temperature-dependent thermal properties of the multicomponent diboride(Ti_(0.25)V_(0.25)Zr_(0.25)Hf_(0.25))B_(2) were obtained by molecular dynamics(mD)simulations driven by a machine learning force field(mLFF)trained on density functional theory(DFT)*** thermal conductivity,density,heat capacity,and coefficient of thermal expansion obtained by the mD simulations were used in time-dependent thermal stress finite element model(FEm)*** low thermal conductivity(m^(-1)·K^(-1))of the multicomponent diboride coupled with its similar coefficient of thermal expansion to that of graphite indicated that stresses of less than 10 GPa were generated at the interface at high temperatures,and therefore,the coating was mechanically resistant to the thermal stress induced during *** experiments at 220℃ showed that the multicomponent diboride coating was resistant to thermal stresses with no visible cracking or *** ablation mechanisms were mechanical denudation and evaporation of B_(2)O_(5) and light V-Ti oxides,which caused a decrease in the mass and thickness of the coating and resulted in mass and linear ablation rates of-0.51 mg·s^(-1) and -1.38μm·s^(-1),respectively,after 60 *** findings demonstrated the thermal and mechanical stability of multicomponent entropy-stabilized diborides as coatings for carbon materials in engineering components under extreme environments.

关键词： entropy-stabilized diborides ultrahigh temperature ceramics molecular dynamics(mD)simulations density functional theory(DFT) ablation properties

The combined effects of farm yard manure and boron application on growth,and oil quality of Canola grown under newly reclaimed soils

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Oil Crop Science 2024年第1期9卷 53-59页

作者： farid Hellal Saied El Sayed Amany Abdel mohsen Ramadan Doaa m.Abobasha Plant Nutrition Department National Research Centre33 El-Behouth St12622DokkiCairoEgypt Botany Department National Research Centre33 El-Behouth St12622DokkiCairoEgypt

Two field experiments were conducted during the main seasons of 2021/2022 at the Research and Production Station of National Research Centre in Egypt to investigate the effects of farmyard manure(FYm)and boron on Canola growth,yield,oil yield,and *** results unequivocally demonstrated that the combined application of FYm at a rate of 14.4 ton ha^(-1)with a foliar spray of boron at 100 ppm positively influenced plant characteristics,leading to enhanced growth rates and higher yields compared to the control ***,this integrated approach significantly improved nutrient content by enhancing levels of oil content,carbohydrates,proteins,phenolics,flavonoids,and total soluble *** findings provide compelling evidence that utilizing farm manure along with boron can effectively enhance Canola properties in newly reclaimed soils while promoting sustainable agricultural practices.

关键词： Oil quality Farmyard manure Phytochemical content Canola Yield production

Analysis of cerium substitution in Co-Sr based spinel ferrites for high frequency application

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Journal of Rare Earths 2024年第9期42卷 1755-1763,I0005页

作者： Laura Khudaysh Inas A.Ahmed Syeda Rabia Ejaz Sajjad Ahmad Khan Yasir A.Haleem mohamed m.Ibrahim mahmood Ali Hafiz muhammad Tahir farid Zeinhom m.El-Bahy Department of Physics Faculty of ScienceJazan UniversityJazan45142Saudi Arabia Department of Chemistry Faculty of ScienceKing Khalid UniversityAbha62224Saudi Arabia Department of Physics The Government Sadiq College Women UniversityBahawalpur63100Pakistan Institute of Physics Khwaja Fareed University of Engineering and Information TechnologyRahim Yar Khan64200Pakistan Department of Chemistry College of ScienceTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Centre of Excellence in Solid State Physics University of the PunjabLahorePakistan Department of Physics Government CollegeTaunsa Sharif32200Pakistan Department of Chemistry Faculty of ScienceAl-Azhar UniversityNasr City11884CairoEgypt

Spinel ferrites exhibit exceptional magnetic properties,making them a distinctive class of magnetic *** sol-gel technique was utilized for the synthesis of spinel ferrites with the chemical formula Co_(0.6)Sr_(0.4)Ce_(x)Fe_(2-x)O_(4). Following that,a comprehensive X-ray diffraction analysis unveiled the crystalline cubic structure of the synthesized *** the utilization of the m-H loop approach,the ferromagnetic attributes of ferrites were assessed,and the assimilation of rare earth elements led to substantial enhancements in saturation magnetization,remanence,and *** ferrites with a high concentration of rare earth elements have improved direct current resistivity and activation *** logarithm of a material's resistance increased from 5.29 to 8.12 Ω·cm as cerium is *** a change in the amount of cerium,the activation energy goes up from 0.19 to *** changing the frequency from 5.5 to 9.5 GHz,the dielectric characteristics were *** the frequency goes up,the dielectric constant goes *** ferrites that have been made better in every way can be used in high-frequency applications.

关键词： Activation energy DC electrical resistance Remanence magnetization Cobalt strontium spinel ferrites High frequency application Rare earths

An integrated computational method for calculating dynamic thermal bridges of building facades in tropical countries

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Frontiers of Architectural Research 2024年第1期13卷 201-218页

作者： miktha farid Alkadri muhammad Rafif Cahyadi Agung Francesco De Luca Research Cluster of Architectural Sciences and Building Technology Department of ArchitectureFaculty of EngineeringUniversitas IndonesiaDepok 16425Indonesia Department of Civil Engineering and Architecture Tallinn University of TechnologyTallinn 19086Estonia

Identifying thermal bridges on building façades has been a great challenge for architects,especially during the conceptual design *** is not only due to the complexity of parameters when calculating thermal bridges,but also lack of feature integration between building energy simulation(BES)tools and the actual building *** example,existing BES tools predominantly calculate thermal bridges only in steady state without considering the temperature dynamic behaviour of building ***,relevant features such as thermal delay,decrement factor,and operative temperature are often neglected,and this can lead to miscalculation of energy *** study then proposes an integrated method to calculate dynamic thermal bridges under transient conditions by incorporating field observations and computational simulations of thermal *** specifically,the proposed method employs several measurement tools such as HOBO data logger to record the actual conditions of indoor and outdoor room temperature and thermal cameras to identify the surface temperature of selected building *** actual datasets are then integrated with the simulation workflow developed in BES *** study ultimately enables architects not only to identify potential thermal bridges on existing building façades but also to support material and geometric exploration in early design phase.

关键词： Thermal bridges Dynamic calculation Thermal delay Cooling load Computational design method

Tensile Strain Capacity Prediction of Engineered Cementitious Composites (ECC) Using Soft Computing Techniques

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Computer modeling in Engineering & Sciences 2024年第3期138卷 2925-2954页

作者： Rabar H.Faraj Hemn Unis Ahmed Hardi Saadullah Fathullah Alan Saeed Abdulrahman farid Abed Civil Engineering Department University of HalabjaHalabjaIraq University of Sulaimani College of EngineeringCivil Engineering DepartmentSulaimaniIraq Civil Engineering Department Komar University of Science and TechnologySulaimaniIraq Department of Engineering Kurdistan Institution for Strategic Studies and Scientific ResearchesSulaimaniIraq Department of Civil Engineering American University of SharjahSharjah26666UAE

Plain concrete is strong in compression but brittle in tension,having a low tensile strain capacity that can significantly degrade the long-term performance of concrete structures,even when steel reinforcing is *** order to address these challenges,short polymer fibers are randomly dispersed in a cement-based matrix to forma highly ductile engineered cementitious composite(ECC).Thismaterial exhibits high ductility under tensile forces,with its tensile strain being several hundred times greater than conventional *** concrete is inherently weak in tension,the tensile strain capacity(TSC)has become one of the most extensively researched *** a result,developing a model to predict the TSC of the ECC and to optimize the mixture proportions becomes ***,the effort required for laboratory trial batches to determine the TSC is *** achieve the research objectives,five distinct models,artificial neural network(ANN),nonlinear model(NLR),linear relationship model(LR),multi-logistic model(mLR),and m5P-tree model(m5P),are investigated and employed to predict the TSCof ECCmixtures containing fly *** from115 mixtures are gathered and analyzed to develop a new *** input variables include mixture proportions,fiber length and diameter,and the time required for curing the various *** model’s effectiveness is evaluated and verified based on statistical parameters such as R2,mean absolute error(mAE),scatter index(SI),root mean squared error(RmSE),and objective function(OBJ)***,the ANN model outperforms the others in predicting the TSC of the ECC,with RmSE,mAE,OBJ,SI,and R2 values of 0.42%,0.3%,0.33%,0.135%,and 0.98,respectively.

关键词： Engineered cementitious composites fly ash curing time tensile strain capacity modeling

Zircon U-Pb ages in the Nuratau ophiolitic mélange in the southern Tianshan,Uzbekistan:Implication for the closure of Paleo-Asian Ocean

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China Geology 2024年第2期7卷 365-368,I0004-I0007页

作者： Kai Weng Ji-fei Cao Divayev-farid Karibovich Jahongir-Jurabekovich movlanov Bo Chen Zhong-ping ma Xi’an Center of Geological Survey China Geological SurveyXi’an 710119China The Center for Geoinnovation Technologies Doctor of Sciences in Geology and mineralogy University of Geological ScienceTashkent 100060Uzbekistan

*** The Central Asian Orogenic Belt(CAOB),which is located between the European craton,Siberian craton,and Tarim-North China craton(Fig.1a),is the largest phanerozoic accretionary orogen in the *** resulted from the longterm subduction and accretion of the Paleo-Asian Ocean(PAO).The PAO has been in existence since at least the late mesoproterozoic(about 1020 ma).However,there has been debate about the closing time of the PAO.

关键词： Asian Paleo Tianshan

Toward a comprehensive hypothesis of oxygen-evolution reaction in the presence of iron and gold

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Journal of Energy Chemistry 2024年第2期89卷 172-183,I0005页

作者： Negah Hashemi Jafar Hussain Shah Cejun Hu Subhajit Nandy Pavlo Aleshkevych Sumbal farid Keun Hwa Chae Wei Xie Taifeng Liu Junhu Wang mohammad mahdi Najafpour Department of Chemistry Institute for Advanced Studies in Basic Sciences(IASBS)Zanjan 45137-66731Iran Center for Advanced mössbauer Spectroscopy Mössbauer Effect Data CenterDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina Key Lab of Advanced Energy materials Chemistry(ministry of Education) Renewable Energy Conversion and Storage CenterCollege of ChemistryNankai UniversityTianjin 300071China Advanced Analysis Center Korea Institute of Science and TechnologySeoul 02792Republic of Korea Institute of Physics Polish Academy of SciencesWarsaw 02-668Poland National and Local Joint Engineering Research Center for Applied Technology of Hybrid Nanomaterials Henan UniversityKaifeng 475004HenanChina Center of Climate Change and Global Warming Institute for Advanced Studies in Basic Sciences(IASBS)Zanjan 45137-66731Iran Research Center for Basic Sciences&modern Technologies(RBST) Institute for Advanced Studies in Basic Sciences(IASBS)Zanjan 45137-66731Iran

This study investigates the effects of Fe on the oxygen-evolution reaction(OER)in the presence of *** distinct areas of OER were identified:the first associated with Fe sites at low overpotential(~330 mV),and the second with Au sites at high overpotential(~870 mV).Various factors such as surface Fe concentration,electrochemical method,scan rate,potential range,concentration,method of adding K_(2)Fe O_(4),nature of Fe,and temperature were varied to observe diverse behaviors during OER for Fe O_(x)H_(y)/*** amounts of Fe ions had a significant impact on OER,reaching a saturation point where the activity did not increase *** electronic interaction between Fe and Au ions was indicated by X-ray photoelectron spectroscopy(XPS)and electron paramagnetic resonance(EPR)*** situ visible spectroscopy confirmed the formation of Fe O_(4)^(2-)during *** situ mossbauer and surfaceenhanced Raman spectroscopy(SERS)analyses suggest the involvement of Fe-based species as intermediates during the rate-determining step of OER.A lattice OER mechanism based on Fe O_(x)H_(y)was proposed for operation at low *** functional theory(DFT)calculations revealed that Fe oxide,Fe-oxide clusters,and Fe doping on the Au foil exhibited different activities and stabilities during *** study provides insights into the interplay between Fe and Au in OER,advancing the understanding of OER mechanisms and offering implications for the design of efficient electrocatalytic systems.

关键词： DFT calculation Fe/Au electrocatalysis mechanism Oxygen evolution Water oxidation

Lubrication effectiveness of composite lubricants during P/m electrostatic die wall lubrication and warm compaction

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Journal of University of Science and Technology Beijing 2006年第6期13卷 528-531页

作者： farid Akhtar materials Science and Engineering School University of Science and Technology BeijingBeijing 100083China

The lubrication effectiveness of the composite lubricants, 50wt% ethylene bis-stearamide （EBS） wax ＋50wt% graphite and 50wt% EBS wax ＋ 50wt% BN, during the powder metallurgy （P/m） electrostatic die wall lubrication and warm compaction was studied. The results show that the combination of 50wt% EBS wax and 50wt% graphite has excellent lubrication performance, resulting in fairly high green densities, but the mixture of 50wt% EBS wax and 50wt% BN has less beneficial effect. In addition, corresponding die temperatures should be applied when different die wall lubricants are used to achieve the highest green densities.

关键词： powder metallurgy composite lubricant electrostatic die wall lubrication warm compaction

Effect of inner oxidant on self-propagating high-temperature synthesis of mnZn-ferrite powder

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Rare metals 2006年第Z1期25卷 553-556页

作者： AKHTAR farid School of materials Science and Engineering University of Science and Technology Beijing

Using KClO3 as an inner oxidant, mnZn-ferrite powder was synthesized by a self-propagating high-temperature synthesis (SHS) process in normal air atmosphere. The effects of the inner oxidant on combustion temperature, combustion velocity, microstructure and the phase of the product were investigated by XRD and SEm,respectively. The results show that a highly ferritized powder can be obtained as well as the highest combustion temperature and the highest combustion velocity when the inner oxidant content m equals 54(k-16).

关键词： inner oxidant self-propagating high-temperature synthesis (SHS) mnZn-ferrite powder