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Journal of Rare Earths 2024年第7期42卷 1385-1393,I0007页

作者： A.Ezaier R.Masrour M.Hamedoun J.kharbach A.Rezzouk A.Hourmatallah N.Benzakour k.bouslykhane Laboratory of Solid Physics Faculty of Sciences Dhar El MehrazSidi Mohamed Ben Abdellah UniversityBP 1796FezMorocco Equipe de Physique du Solide LaboratoiresLIPIEcole Normale SupérieureBensoudaFèsMorocco

In this paper,we analyzed the physical characteristics of the ternary alloys RE_(2)Rh_(3)Ge(RE=Pr and Sm)using the first principles calculation based on functional density theory integrated in the Wien2k *** calculated formation energies of Pr_(2)Rh_(3)Ge and Sm_(2)Rh_(3)Ge are−5.3827 and−5.2782 eV/atom,respectively,showing that these alloys may exist *** results of the band structure and density of states indicate that all of the compounds tested are magnetic metals,and their magnetism is mostly related to the contribution of Pr and Sm *** total magnetic moments of Pr_(2)Rh_(3)Ge and Sm_(2)Rh_(3)Ge are 4.07245 and 11.16161μB/f.u,*** parameters such as heat capacity at constant pressure,entropy,Debye temperature,lattice volume,compressibility coefficients,and Grüneisen parameter alloys were calculated using the Gibbs algorithm and studied in depth over a large temperature range of 0-900 *** Debye temperature increases with increasing pressure and decreases with decreasing ***,the Debye temperatures calculated at p=0 GPa and T=300 k are equal to be 342 and 322 k for Pr_(2)Rh_(3)Ge and Sm_(2)Rh_(3)Ge,*** optical characteristics such as the real and imaginary portions of the dielectric function,the absorption coefficient,the energy-loss function,and the refractive index were investigated and discussed in more depth.

关键词： Magnetic metals Functional density theory Density of states Magnetic moment Optical and thermodynamic properties Rare earths

Effect of Zn Substitution on Magnetic Properties of CuFe_2O_4： a High-Temperature Series Expansions Study

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Chinese Physics Letters 2018年第1期35卷 95-98页

作者： S.Salmi R.Masrour A.El Grini k.bouslykhane A.Hourmatallah N.Benzakour M.Hamedoun Laboratoire de Physique du Solide Universite Sidi Mohammed Ben Abdellah Faculte des sciences Dhar Mahraz BP 1796 Fes Morocco Laboratory of Materials Processes Environment and Quality Cady Ayyed University National School of Applied Sciences Route Sidi Bouzid-BP 63 46000 Sail Morocco Equipe de Physique du Solide Laboratoire LIPI Ecole Normale Superieure BP 5206 Bensouda Fes Morocco MASc IR Foundation Institut of Nanomaterials and Nanotechnologies Materials & Nanomaterials Center B.P. 10100Rabat Morocco

The magnetic properties of spinel ferrites Cu_（1-x）Zn_xFe_2O_4 are studied using high-temperature series expansions combined with the Padé approximates. The exchange interactions, inter and intra-sublattices J_（AA）, J_（BB） and J_（AB） are obtained using a probability distribution law. The critical exponent associated with the magnetic susceptibility is obtained.

关键词： Cu Zn Effect of Zn Substitution on Magnetic Properties of CuFe_2O_4

Spin and Orbital Magnetisms of NiFe Compound:Density Functional Theory Study and Monte Carlo Simulation

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Chinese Physics Letters 2018年第3期35卷 58-61页

作者： R.Masrour A.Jabar E.k.Hlil M.Hamedoun A.Benyoussef A.Hourmatallah k.bouslykhane A.Rezzouk N.Benzakour Laboratory of Materials ProcessesEnvironment and QualityCady Ayyed UniversityNational School of Applied SciencesSail 63 46000Morocco Institut Neel CNRS et Universite Grenoble AlpesBP 166F-38042 Grenoble Cedex 9France Institute of Nanomaterials and Nanotechnologies MAScIRRabatMorocco Hassan II Academy of Science and Technology RabatMorocco Equipe de Physique du Solide Laboratoire LIPIEcole Normale SuperieureBP 5206BensoudaFesMorocco Laboratoire de Physique du Solide Universite Sidi Mohammed Ben AbdellahFaculte des Sciences Dhar MahrazBP 1796FesMorocco

The self-consistent ab initio calculations based on the density functional theory approach using the full potential linear augmented plane wave method are performed to investigate both the electronic and magnetic properties of the NiFe compound. Polarized spin within the framework of the ferromagnetic state between magnetic ions is considered. Also, magnetic moments considered to lie along （001） axes are computed. The Monte Carlo simulation is used to study the magnetic properties of NiFe. The transition temperature To, hysteresis loop, coercive field and remanent magnetization of the NiFe compound are obtained using the Monte Carlo simulation.

关键词： Fe Spin and Orbital Magnetisms of Ni Fe Compound Ni

Aqueous-phase reforming of hydroxyacetone solution to bio-based H_(2)over supported Pt catalysts

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Green Energy & Environment 2024年第4期9卷 777-788页

作者： A.k.k.Vikla k.koichumanova Songbo He k.Seshan Joint International Research Laboratory of Circular Carbon Nanjing Tech UniversityNanjing211816China Faculty of Science and Technology University of Twente7500 AE EnschedeThe Netherlands CoRe Pro 9723 BL GroningenThe Netherlands

Aqueous-phase reforming(APR)is an attractive process to produce bio-based hydrogen from waste biomass streams,during which the catalyst stability is often challenged due to the harsh reaction *** this work,three Pt-based catalysts supported on C,AlO(OH),and ZrO_(2)were investigated for the APR of hydroxyacetone solution in afixed bed reactor at 225℃and 35 *** them,the Pt/C catalyst showed the highest turnover frequency for H_(2)production(TOF of 8.9 molH_(2)molPt^(-1)min^(-1))and the longest catalyst *** the AlO(OH)and ZrO_(2)supported Pt catalysts,the side reactions consuming H_(2),formation of coke,and Pt sintering result in a low H_(2)production and the fast catalyst *** proposed reaction pathways suggest that a promising APR catalyst should reform all oxygenates in the aqueous phase,minimize the hydrogenation of the oxygenates,maximize the WGS reaction,and inhibit the condensation and coking reactions for maximizing the hydrogen yield and a stable catalytic performance.

关键词： APR Hydroxyacetone TOF Bio-based H_(2) Support effect

Direct scaling of residual displacements for bilinear and pinching oscillators

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 129-149页

作者： Mohammad Saifullah Vinay k.Gupta Department of Civil Engineering Indian Institute of Technology KanpurKanpur 208016India

The estimation of residual displacements in a structure due to an anticipated earthquake event has increasingly become an important component of performance-based earthquake engineering because controlling these displacements plays an important role in ensuring cost-feasible or cost-effective repairs in a damaged structure after the *** attempt is made in this study to obtain statistical estimates of constant-ductility residual displacement spectra for bilinear and pinching oscillators with 5%initial damping,directly in terms of easily available seismological,site,and model *** of the available models for the bilinear and pinching oscillators are useful when design spectra for a seismic hazard at a site are not *** statistical estimates of a residual displacement spectrum are proposed in terms of earthquake magnitude,epicentral distance,site geology parameter,and three model parameters for a given set of ductility demand and a hysteretic energy capacity coefficient in the case of bilinear and pinching models,as well as for a given set of pinching parameters for displacement and strength at the breakpoint in the case of pinching model *** proposed scaling model is applicable to horizontal ground motions in the western *** earthquake magnitudes less than 7 or epicentral distances greater than 20 km.

关键词： residual displacement spectrum bilinear hysteresis model pinching hysteresis model nonlinear analysis scaling model

Analysis of the Oscillatory Flows of Multiple Shock Waves in a Constant Area Duct

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Journal of Thermal Science 2024年第3期33卷 794-806页

作者： k JAMES Jintu kIM Heuy Dong Department of Mechanical Engineering Andong National UniversityAndong36729Republic of Korea CAD-IT korea Co. Ltd.Seoul08591Republic of Korea

The oscillatory response of multiple shock waves to downstream perturbations in a supersonic flow is studied numerically in a rectangular *** shock waves are formed inside the duct at a shock Mach number of *** duct has an exit height of H,and the effect of duct resonance on multiple shock oscillations is investigated by attaching exit ducts of lengths 0H,50H,and *** downstream disturbance frequency varied from 10 Hz to 200 Hz to explore the oscillation characteristics of the multiple shock *** oscillatory response of shock waves under self-excited and forced oscillation conditions are analyzed in terms of wall static pressure,shock train leading-edge location,shock train length,and the size of the separation *** extent of the initial shock location increases with an increase in exit duct length for the self-excited oscillation *** analysis of the shock train leading edge and the spectral analysis of wall static pressure variations are *** variation in the shock train length is analyzed using the pressure ratio method for self-excited as well as forced *** RMS amplitude of the normalized shock train length(ζ_(ST))increases with an increase in the exit duct length for the self-excited oscillation *** the downstream perturbation frequency is increased,ζ_(ST)is decreased for exit duct *** all exit duct designs and downstream forcing frequencies,the size of the separation bubble grows and shrinks during the shock oscillations,demonstrating the dependence on duct resonance and forced oscillations.

关键词： shock train downstream disturbance supersonic flow shock wave boundary layer interaction duct resonance flow separation

Impact of Fin Arrangement on Heat Transfer and Melting Characteristics of Phase Change Material

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Journal of Thermal Science 2024年第2期33卷 435-456页

作者： Arun UNIYAL Yogesh k.PRAJAPATI Department of Mechanical Engineering National Institute of Technology UttarakhandSrinagar(Garhwal)246174India Department of Mechanical Engineering BIT SindriDhanbadJharkhand828123India

Present work investigates the heat transfer and melting behaviour of phase change material(PCM) in six enclosures(enclosure-1 to 6) filled with paraffin *** enclosures are equipped with distinct arrangements of the fins while keeping the fin's surface area equal in each *** analysis has been presented to recognize the suitable fin arrangements that facilitate improved heat transfer and melting rate of the *** wall of the enclosure is maintained isothermal for the temperature values 335 k,350 k and 365 *** length of the enclosure including fins is ranging between 0 and *** have been illustrated through the estimation of important performance parameters such as energy absorbing capacity,melting rate,enhancement ratio,and Nusselt *** has been found that melting time(to melt 100% of the PCM) is 60.5%less in enclosure-2(with two fins of equal length) as compared to the enclosure-1,having no *** the fin surface area equal,if the longer fin is placed below the shorter fin(enclosure-3),melting time is further decreased by 14.1% as compared to ***,among all the configurations,enclosure-6 with wire-mesh fin structure exhibits minimum melting time which is 68.4% less as compared to the *** on the findings,it may be concluded that fins are the main driving agent in the enclosure to transfer the heat from heated wall to the *** design and positioning of the fins improve the heat transfer rate followed by melting of the PCM in the entire area of the *** of the favourable vortices and natural convection current in the enclosure accelerate the melting phenomenon and help to reduce charging time.

关键词： phase change material enclosure fin melting fraction energy storage heat transfer

Radiative heat transfer analysis of a concave porous fin under the local thermal non-equilibrium condition:application of the clique polynomial method and physics-informed neural networks

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Applied Mathematics and Mechanics(English Edition) 2024年第9期45卷 1613-1632页

作者： k.CHANDAN k.kARTHIk k.V.NAGARAJA B.C.PRASANNAkUMARA R.S.VARUN kUMAR T.MUHAMMAD Amrita School of Artificial Intelligence Amrita Vishwa VidyapeethamBengaluru 560035KarnatakaIndia Department of Studies in Mathematics Davangere UniversityDavangere 577002KarnatakaIndia Computational Science Lab Amrita School of EngineeringAmrita Vishwa VidyapeethamBengaluru 560035KarnatakaIndia Department of Pure and Applied Mathematics School of Mathematical SciencesSunway UniversityPetaling Jaya 47500Malaysia Department of Mathematics College of ScienceKing Khalid UniversityAbha 61413Saudi Arabia

The heat transfer through a concave permeable fin is analyzed by the local thermal non-equilibrium(LTNE)*** governing dimensional temperature equations for the solid and fluid phases of the porous extended surface are modeled,and then are nondimensionalized by suitable dimensionless ***,the obtained nondimensional equations are solved by the clique polynomial method(CPM).The effects of several dimensionless parameters on the fin's thermal profiles are shown by graphical ***,the current study implements deep neural structures to solve physics-governed coupled equations,and the best-suited hyperparameters are attained by comparison with various network *** results of the CPM and physicsinformed neural network(PINN)exhibit good agreement,signifying that both methods effectively solve the thermal modeling problem.

关键词： heat transfer fin porous fin local thermal non-equilibrium(LTNE)model physics-informed neural network(PINN)

MDCN:Modified Dense Convolution Network Based Disease Classification in Mango Leaves

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Computers, Materials & Continua 2024年第2期78卷 2511-2533页

作者： Chirag Chandrashekar k.P.Vijayakumar k.Pradeep A.Balasundaram School of Computer Science and Engineering Vellore Institute of Technology(VIT)ChennaiIndia Center for Cyber Physical Systems School of Computer Science and EngineeringVellore Institute of Technology(VIT)ChennaiIndia

The most widely farmed fruit in the world is *** the production and quality of the mangoes are hampered by many *** diseases need to be effectively controlled and ***,a quick and accurate diagnosis of the disorders is *** convolutional neural networks,renowned for their independence in feature extraction,have established their value in numerous detection and classification ***,it requires large training datasets and several parameters that need careful *** proposed Modified Dense Convolutional Network(MDCN)provides a successful classification scheme for plant diseases affecting mango *** model employs the strength of pre-trained networks and modifies them for the particular context of mango leaf diseases by incorporating transfer learning *** data loader also builds mini-batches for training the models to reduce training ***,optimization approaches help increase the overall model’s efficiency and lower computing *** employed on the MangoLeafBD Dataset consists of a total of 4,000 *** the experimental results,the proposed system is compared with existing techniques and it is clear that the proposed algorithm surpasses the existing algorithms by achieving high performance and overall throughput.

关键词： Leaf disease detection deep convolutional neural networks transfer learning optimization MangoLeafBD Dataset

Understanding the corrosion and bio-corrosion behaviour of Magnesium composites – a critical review

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Journal of Magnesium and Alloys 2024年第3期12卷 890-939页

作者： Prithivirajan Sekar S.k.Panigrahi Department of Mechanical Engineering Indian Institute of Technology MadrasChennai600036India Applied Magnesium Research Center Center of Excellence in Materials and Manufacturing for Futuristic MobilityIndian Institute of Technology MadrasChennai600036India

Realising the potential of Magnesium(Mg),several globally leading ventures have invested in the Mg industry,but their relatively poor corrosion resistance is a never ending saga till *** corrosion and bio-corrosion behaviour of Mg has gained research attention and still remains a hot topic in the application of automobile,aerospace and biomedical *** intrinsic high electrochemical nature of Mg limits their utilization in diverse *** scenario has prompted the development of Mg composites with an aim to achieve superior corrosion and bio-corrosion *** present review enlightens the influence of grain size(GS),secondary phase,texture,type of matrix and reinforcement on the corrosion and bio-corrosion behaviour of Mg ***,the corrosion and bio-corrosion behaviour of Mg composites manufactured by primary and secondary processing routes are ***,the comprehensive corrosion and bio-corrosion mechanisms of these Mg composites are ***,the individual role of GS,texture and corrosive medium on corrosion and bio-corrosion behaviour of Mg composites are clarified and *** challenges encountered,unanswered issues in this field are explained in detail and accordingly the scope for future research is *** review is presented from basic concrete background to advanced corrosion mechanisms with an aim of creating interest among the readers like students,researchers and industry experts from various research ***,the corrosion and bio-corrosion behaviour of Mg composites are critically reviewed for the first time to:(i)contribute to the body of knowledge,(ii)foster research and development,(iii)make breakthrough,and(iv)create life changing innovations in the field of Mg composite corrosion.

关键词： Corrosion Bio corrosion Magnesium alloys Magnesium composites Magnesium implants.