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Strain-Rate Dependency of a Unidirectional Filament Wound Composite under Compression

Computer Modeling in Engineering & Sciences 2023年第12期137卷 2149-2161页

作者： Stepan Konev victor a.eremeyev Hamid M.Sedighi Leonid Igumnov Anatoly Bragov Aleksandr Konstantinov Ayaulym Kuanyshova Ivan Sergeichev Skolkovo Institute of Science and Technologies Center for Materials TechnologiesMoscowRussia National Research Lobachevsky State University of Nizhny Novgorod Nizhny NovgorodRussia Dipartimento di Ingegneria Civile Ambientale e Architettura(DICAAR)Universitàdegli Studi di CagliariCagliari(CA)Italy Mechanical Engineering Department Faculty of EngineeringShahid Chamran University of AhvazAhvazIran Drilling Center of Excellence and Research Center Shahid Chamran University of AhvazAhvazIran

This article presents the results of experimental studies concerning the dynamic deformation and failure of a unidirectional carbon fiber reinforced plastic(T700/LY113)under *** test samples were manufactured through the filament winding of flat *** establish the strain rate dependencies of the strength and elastic modulus of the material,dynamic tests were carried out using a drop tower,the Split Hopkinson Pressure Bar method,and standard static *** samples were loaded both along and perpendicular to the direction of the reinforcing *** applicability of the obtained samples for static and dynamic tests was confirmed through finite elementmodeling and the high-speed imaging of the deformation and failure of samples during *** a result of the conducted experimental studies,static and dynamic stress-strain curves,time dependencies of deformation and the stress and strain rates of the samples during compression were *** on these results,the strain rate dependencies of the strength and elasticity modulus in the strain rate range of 0.001-6001/s are *** is shown that the strain rate significantly affects the strength and deformation characteristics of the unidirectional carbon fiber composites under *** increase in the strain rate by 5 orders of magnitude increased the strength and elastic modulus along the fiber direction by 42%and 50%,*** loading resulted in a strength and elastic modulus increase by 58%and 50%,*** average strength along the fibers at the largest studied strain rate was about *** obtained results can be used to design structural elements made of polymer composite materials operating under dynamic shock loads,as well as to build models of mechanical behavior and failure criteria of such materials,taking into account the strain rate effects.

关键词： High strain rate composites filament winding dynamic strength Split Hopkinson Pressure Bar compression

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Heating of nanoparticles and their environment by laser radiation and applications

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Nanotechnology and Precision Engineering 2024年第1期7卷 78-115页

作者： victor K.Pustovalov Belarusian National Technical University Pr.Independency65Minsk 220013Belarus

This review considers the fundamental dynamic processes involved in the laser heating of metal nanoparticles and their subsequent *** particular interest are the absorption of laser energy by nanoparticles,the heating of a single nanoparticle or an ensemble thereof,and the dissipation of the energy of nanoparticles due to heat exchange with the *** goal is to consider the dependences and values of the temperatures of the nanoparticles and the environment,their time scales,and other parameters that describe these *** results and analytical studies on the heating of single metal nanoparticles by laser pulses are discussed,including the laser thresholds for initiating subsequent photothermal processes,how temperature inﬂuences the optical properties,and the heating of gold nanoparticles by laser *** studies of the heating of an ensemble of nanoparticles and the results of an analytical study of the heating of an ensemble of nanoparticles and the environment by laser radiation are *** methods for nanoparticles under laser heating are considered,including changes in the refractive indices of metals and spectral thermometry of optical scattering of nanoparticles,Raman spectroscopy,the thermal distortion of the refractive index of an environment heated by a nanoparticle,and thermochemical phase transitions in lipid bilayers surrounding a heated *** the sequence of events after radiation absorption and their time scales underlies many applications of *** applicationﬁelds for the laser heating of nanoparticles are reviewed,including thermochemical reactions and selective nanophotothermolysis initiated in the environment by laser-heated nanoparticles,thermal radiation emission by nanoparticles and laser-induced incandescence,electron and ion emission of heated nanoparticles,and optothermal chemical *** of the laser heating of nanoparticles in la

关键词： Nanoparticles Laser Heating Modeling Nanothermometry Applications

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Seamless morphing trailing edge flaps for UAS-S45 using high-fidelity aerodynamic optimization

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Chinese Journal of Aeronautics 2024年第2期37卷 12-29页

作者： Mir Hossein NEGAHBAN Musavir BASHIR victor TRAISNEL Ruxandra Mihaela BOTEZ LARCASE Laboratory of Applied Research in Active Controls Avionics and AeroservoelasticityEcole de Technologie SuperieureUniversite du QuebecMontreal H3C1K3Canada

The seamless trailing edge morphing flap is investigated using a high-fidelity steady-state aerodynamic shape optimization to determine its optimum configuration for different flight conditions,including climb,cruise,and gliding descent.A comparative study is also conducted between a wing equipped with morphing flap and a wing with conventional hinged *** optimization is performed by specifying a certain objective function and the flight performance goal for each flight *** the climb rate,extending the flight range and endurance in cruise,and decreasing the descend rate,are the flight performance goals covered in this *** optimum configurations were found for the morphing wing by determining the optimum morphing flap deflection for each flight condition,based on its objective function,each of which performed better than that of the baseline *** was shown that by using optimum configuration for the morphing wing in climb condition,the required power could be reduced by up to 3.8%and climb rate increases by 6.13%.The comparative study also revealed that the morphing wing enhances aerodynamic efficiency by up to 17.8%and extends the laminar ***,the optimum configuration for the gliding descent brought about a 43%reduction in the descent rate.

关键词： Seamless morphing trailing edge flap Aerodynamic optimization Gradient-based optimiza-tion Climb flight condition Gliding descent Flight range Endurance

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Dynamics of Low-Viscosity Liquids Interface in an Unevenly Rotating Vertical Layer

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Fluid Dynamics & Materials Processing 2024年第4期20卷 693-703页

作者： victor Kozlov Vladimir Saidakov Nikolai Kozlov Laboratory of Vibrational Hydromechanics Perm State Humanitarian Pedagogical UniversityPerm614990Russia Institut de Mécanique des Fluides de Toulouse Toulouse INPToulouse31400France

The behavior of two immiscible low-viscosity liquids differing in density and viscosity in a vertical flat layer undergoing modulated rotation is experimentally *** layer has a circular axisymmetric *** the absence of modulation of the rotation speed,the interphase boundary has the shape of a short axisymmetric cylinder.A new effect has been discovered,under the influence of rotation speed modulation,the interface takes on a new dynamic equilibrium state.A more viscous liquid covers the end boundaries of the layer in the form of thin films,which have the shape of round spots of almost constant radius;with increasing amplitude of the velocity modulation,the wetting boundary *** is found that upon reaching the critical amplitude of oscillations,the film of a viscous liquid loses stability,and the outer edge of the wetting spot collapses and takes on a feathery *** is shown that this threshold is caused by the development of the Kelvin-Helmholtz oscillatory instability of the *** spreading radius of a spot of light viscous liquid and its stability are studied depending on the rotation rate,amplitude,and frequency of rotation speed *** discovered averaged effects are determined by different oscillatory interaction of fluids with the end-walls of the cell,due to different *** effect of films forming can find application in technological processes to intensify mass transfer at interphase boundaries.

关键词： Rotation oscillations immiscible fluids contact line interface film dynamic equilibrium Nomenclature frot

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Using deep neural networks coupled with principal component analysis for ore production forecasting at open-pit mines

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 727-740页

作者： Chengkai Fan Na Zhang Bei Jiang Wei victor Liu Department of Civil and Environmental Engineering University of AlbertaEdmontonAlbertaT6G 2E3Canada Department of Mathematical and Statistical Sciences University of AlbertaEdmontonAlbertaT6G 2G1Canada

Ore production is usually affected by multiple influencing inputs at open-pit ***,the complex nonlinear relationships between these inputs and ore production remain *** becomes even more challenging when training data(*** haulage information and weather conditions)are *** machine learning(ML)algorithms,deep neural network(DNN)is a superior method for processing nonlinear and massive data by adjusting the amount of neurons and hidden *** study adopted DNN to forecast ore production using truck haulage information and weather conditions at open-pit mines as training *** the prediction models were built,principal component analysis(PCA)was employed to reduce the data dimensionality and eliminate the multicollinearity among highly correlated input *** verify the superiority of DNN,three ANNs containing only one hidden layer and six traditional ML models were established as benchmark *** DNN model with multiple hidden layers performed better than the ANN models with a single hidden *** DNN model outperformed the extensively applied benchmark models in predicting ore *** can provide engineers and researchers with an accurate method to forecast ore production,which helps make sound budgetary decisions and mine planning at open-pit mines.

关键词： Oil sands production Open-pit mining Deep learning Principal component analysis(PCA) Artificial neural network Mining engineering

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Efficient cold atom source from a single-layer atom chip

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Chinese Optics Letters 2024年第6期22卷 103-108页

作者： Petr Skakunenko Darya Bykova Anton Afanasiev Alexey Kalmykov Roman Kirtaev victor Balykin Institute of Spectroscopy Russian Academy of Sciences Moscow 108840Russia Moscow Institute of Physics and Technology Moscow 141700Russia Skolkovo Institute of Science and Technology Moscow 121205Russia National Research University Higher School of Economics Moscow 101000Russia Present affiliation:Emerging Technologies Research Center XPANCEODubaiUnited Arab Emirates

We developed a new single-layer atom chip with an additional U-shaped current-carrying *** new U-shaped microwire creates optimized magnetic field distribution,which increases the trapping volume of a magneto-optical trap(MOT) near the *** approach allows one to localize more atoms,while a setup remains relatively simple (single-layer approach) and consumes low current (up to 10 A). The total number of trapped^(87)Rb atoms in our setup is 5×10^(7).

关键词： atom chip cold atoms laser cooling magneto-optical trap U-MOT

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Formation of diffuse and spark discharges between two needle electrodes with the scattering of particles

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Plasma Science and Technology 2024年第9期26卷 32-39页

作者： victor F TARASENKO Dmitry V BELOPLOTOV Alexei N PANCHENKO Dmitry A SOROKIN Institute of High Current Electronics Siberian BranchRussian Academy of SciencesTomsk 634055Russia National Research Tomsk State University Tomsk 634050Russia

The development of a nanosecond discharge in a pin-to-pin gap filled with air at atmospheric pressure has been studied with high temporal and spatial resolutions from a breakdown start to the spark *** and negative nanosecond voltage pulses with an amplitude of tens of kilovolts were ***-resolved images of the discharge development were taken with a fourchannel Intensified Charge Coupled Device(ICCD)*** minimum delay between the camera channels could be as short as≈0.1 *** made it possible to study the gap breakdown process with subnanosecond *** was observed that a wide-diameter streamer develops from the high-voltage pointed *** ionization processes near the grounded pin electrode started when the streamer crossed half of the *** bridging the gap by the streamer,a diffuse discharge was *** development of spark leaders from bright spots on the surface of the pointed electrodes was observed at the next *** was found that the rate of development of the spark leader is an order of magnitude lower than that of the wide-diameter *** thin luminous tracks were observed against the background of a discharge plasma *** has been established that the tracks are adjacent to brightly glowing spots on the electrodes and are associated with the flight of small particles.

关键词： needle electrodes short voltage pulses atmospheric air streamer breakdown diffuse and spark discharges scattering metal particles

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New approach for particle size and shape analysis of iron-based oxygen carriers at multiple oxidation states

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Particuology 2024年第7期90卷 493-503页

作者： victor Purnomo Marcelo Dal Belo Takehara Robin Faust Lidiya Abdisa Ejjeta Henrik Leion Division of Energy and Materials Department of Chemistry and Chemical EngineeringChalmers University of TechnologyGöteborg 41258Sweden Division of Energy Science Department of Engineering Sciences and MathematicsLuleåUniversity of TechnologyLuleå97187Sweden

One of the crucial issues in the chemical looping technology lies in its bed material:the oxygen *** size analysis of an oxygen carrier is important since in a fluidized bed the material can only work well within a specific size *** the favorable size ranges for oxygen carrier materials have already been reported,none of the published studies has analyzed the particle size and shape of oxygen carriers in ***,the effect of oxygen carriers'oxidation degree on such properties has not been considered *** study aimed to report the particle size and shape analysis of five iron-based oxygen carriers,one natural ore,one synthetic material,and three residue products,at different oxidation degrees using dynamic image analysis(DIA).The oxygen carriers were prepared at different mass conversion degrees in a fluidized bed batch *** size distribution,sphericity,and aspect ratio of the oxygen carrier particles were examined experimentally using a Camsizer *** results show that the DIA method was successfully able to analyze the particle size and shape of our oxygen carriers with satisfying accuracy for *** oxidation state of the investigated materials seems to only affect the particle size and shape of oxygen carriers to a minor ***,exposures to redox cycles in a fluidized bed reactor may alter the particle size and shape of most oxygen carriers.

关键词： Oxygen carrier Size and shape analysis Dynamic image analysis Oxidation state Fluidized bed Chemical looping

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Digital monitoring of rotary-percussive drilling with down-the-hole hammer for profiling weathered granitic ground

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1615-1636页

作者： Wendal victor Yue Siyuan Wu Manchao He Yafei Qiao Zhongqi Quentin Yue Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai200092China Department of Civil Engineering Faculty of EngineeringThe University of Hong KongPokfulam RoadHong KongChina State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyBeijing100083China Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Tongji UniversityShanghai200092China

Rock and geotechnical engineering investigations involve drilling holes in ground with or without retrieving soil and rock samples to construct the subsurface ground *** the basis of an actual soil nailing drilling for a slope stability project in Hong Kong,this paper further develops the drilling process monitoring(DPM)method for digitally profiling the subsurface geomaterials of weathered granitic rocks using a compressed airflow driven percussive-rotary drilling machine with down-the-hole(DTH)*** transducers are installed on the drilling machine and record the chuck displacement,DTH rotational speed,and five pressures from five compressed airflows in real-time *** mechanism and operations of the drilling machine are elaborated in detail,which is essential for understanding and evaluating the drilling data.A MATLAB program is developed to automatically filter the recorded drilling data in time series and classify them into different drilling processes in sub-time *** processes include penetration,push-in with or without rod,pull-back with or without rod,rod-tightening and *** drilling data are further reconstructed to plot the curve of drill-bit depth versus the net drilling time along each of the six *** curve is found to contain multiple linear segments with a constant penetration rate,which implies a zone of homogenous geomaterial with different weathering *** effect from fluctuation of the applied pressures is evaluated *** analyses are presented for accurately assess and verify the underground profiling and strength in weathered granitic rock,which provided the basis of using DPM method to confidently assess drilling measurements to interpret the subsurface profile in real time.

关键词： Drilling process monitoring(DPM) Down-the-hole(DTH)hammer Percussive-rotary drilling Weathering granitic rocks

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The relationship between morphology and flight in Drosophila:a study of two pairs of sibling species from a natural population

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Insect Science 2024年第3期31卷 885-900页

作者： Nicolás Flaibani victoría Estefania Ortiz Juan JoséFanara Valeria Paula Carreira Laboratorio de Evolucion Departamento de EcologiaGenética y Evolucion(DEGE)Facultad de Ciencias Exactas y Naturales(FCEN)Universidad de Buenos Aires(UBA)Instituto de GenéticaEcologia y Evolucion de Buenos Aires(IEGEBA)Consejo Nacional de Investigaciones Cientificasy Tecnicas(CONICET)-UBABuenos AiresArgentina

Insect flight is a complex trait involved in different behaviors,from the search for sexual partners,food,or breeding *** studies have postulated the adaptive advantages of certain morphological traits in relation to increased flight capacity,such as low values of wing loading or high values of wing:thorax ratio and wing-aspect ***,few studies have evaluated the relationship between variables related to flight and morphological traits in *** work aimed to study morphological traits in males and females of two pairs of sibling species:Drosophila buzzati Patterson and Wheeler-Drosophila koeferae Fontdevila and Wasserman,and Drosophila melanogaster Meigen-Drosophila simulans Sturtevant,and to analyze its relationship with *** detected the highest proportion of flight time in *** and *** compared to *** and ***,*** results also revealed sexual dimorphism,with males exhibiting a higher proportion of flight time than ***,we did not find a general pattern to explain the relationship between morphology and the proportion of flight time because associations varied depending upon the analyses(considering all groups together or each sex-species combination separately).Moreover,these associations explained a low percentage of variation,suggesting that other nonmorphological components related to flight,such as physiological variables,should be taken into *** work allowed us to show the variability and complexity of an aspect of flight,suggesting that the adaptive role of the morphological traits studied might have been overestimated.

关键词： morphological traits time in flight wing loading wing:thorax ratio wingaspect ratio wing second moment of area

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