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Research in Cold and Arid Regions 2017年第3期9卷 197-204页

作者： alexey piotrovich Svetlana Zhdanova Far Eastern State Transport University

This paper lists difficult railway construction conditions that are typical for the northern areas of the Russian Far ***-bound issues of railway and highway construction and operation are *** of the authors'developme... 详细信息

关键词： permafrost subgrade reinforcement techniques

Convection and Stratification of Temperature and Concentration

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Fluid Dynamics & Materials Processing 2024年第6期20卷 1351-1364页

作者： alexey Fedyushkin Laboratory of Complex Fluid Mechanics Ishlinsky Institute for Problems in Mechanics RASMoscow119526Russia

This study is devoted to an analysis of natural convection and the emergence of delamination in an incompressible fluid encapsulated in a closed region heated from the ***,medium and intensive modes of stationary laminar thermal and thermo-concentration convection are *** is shown that nonlinear flow features can radically change the flow structure and characteristics of heat and mass ***,the temperature and concentration segregation in the center of the square region display a non-monotonic dependence on the Grashof number(flow intensity).The formation of a nonstationary periodic structure of thermal convection in boundary layers and in the core of a convective flow in the closed region is also *** of the formation of countercurrents inside the region with the direction opposite to the main convective flow are ***,the influence of vertical and horizontal vibrations on oscillatory convection is analyzed in detail.

关键词： Natural convection stratification segregation numerical simulation vibrations

Method for passivation of propellant residues in orbital stage tank of launch vehicle

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Chinese Journal of Aeronautics 2024年第1期37卷 64-76页

作者： Valeriy TRUSHLYAKOV Ivan LESNYAK alexey PANICHKIN Department of Aviation and Rocket Building Omsk State Technical UniversityOmsk 644050Russia Sobolev Institute of Mathematics of the Siberian Branch of Russian Academy of Sciences Novosibirsk 630090Russia

The problem of removing unused liquid propellant residues from the tanks of spent spacecraft and orbital stages of Launch Vehicles(LV)leads to their explosion and the formation of space debris in *** provide a solution to this problem,a method for removing liquid propellant residues from the LV tanks after the mission completion is *** method is based on the gasification of liquid propellant residues in the tanks under acoustic-vacuum exposure and the discharge of the gasification products into the surrounding outer *** investigations were carried out on a Ground-based Experimental Installation(GEI)to determine the coefficient of heat transfer from the surface of an acoustic radiator to a *** obtained coefficient was then used to calculate the energy costs for the gasification of *** estimates are given on the example of the tank with kerosene residues from a spent second stage of the LV“Soyuz-2.1 v”.The optimal discharge rate at which kerosene does not freeze is 0.14 m^(3)/***,the acoustic exposure leads to an increase in the mass of evaporated kerosene over a given time by96.1%,and the energy costs are 1756.7 kJ(approximately 50% of the remaining electrical energy).

关键词： Propellant Weightlessness Liquid evaporation Heat and mass transfer Acoustics Vacuum Vapor bubbles

Advances in laser-plasma interactions using intense vortex laser beams

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Science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 14-42页

作者： Yin Shi Xiaomei Zhang alexey Arefiev Baifei Shen Department of Plasma Physics and Fusion Engineering University of Science and Technology of ChinaHefei 230026China Department of Physics Shanghai Normal UniversityShanghai 200234China Department of Mechanical and Aerospace Engineering University of California at San DiegoLa JollaCA 92093USA

Low-intensity light beams carrying orbital angular momentum(OAM),commonly known as vortex beams,have garnered significant attention due to promising applications in areas ranging from optical trapping to *** recent years,there has been a surge in global research exploring the potential of high-intensity vortex laser beams and specifically their interactions with *** paper provides a comprehensive review of recent advances in this *** with conventional laser beams,intense vortex beams exhibit unique properties such as twisted phase fronts,OAM delivery,hollow intensity distribution,and spatially isolated longitudinal *** distinct characteristics give rise to a multitude of rich phenomena,profoundly influencing laser-plasma interactions and offering diverse *** paper also discusses future prospects and identifies promising general research areas involving vortex *** areas include low-divergence particle acceleration,instability suppression,high-energy photon delivery with OAM,and the generation of strong magnetic *** growing scientific interest and application potential,the study of intense vortex lasers is poised for rapid development in the coming years.

关键词： intense vortex laser orbital angular momentum laser plasma interactions high power laser high energy density science

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

Influence of the Atlantic Multidecadal Oscillation and Interdecadal Pacific Oscillation on Antarctic surface air temperature during 1900 to 2015

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Acta Oceanologica Sinica 2024年第3期43卷 48-58页

作者： Cuijuan Sui Lejiang Yu alexey YuKarpechko Licheng Feng Shan Liu Key Laboratory of Marine Hazards Forecasting National Marine Environmental Forecasting CenterMinistry of Natural ResourcesBeijing 100081China Key Laboratory for Polar Science Polar Research Institute of ChinaMinistry of Natural ResourcesShanghai 200136China Finnish Meteorological Institute HelsinkiFI-00101Finland

The importance of the Atlantic Multidecadal Oscillation(AMO)and Interdecadal Pacific Oscillation(IPO)in influencing zonally asymmetric changes in Antarctic surface air temperature(SAT)has been ***,previous studies have primarily concentrated on examining the combined impact of the contrasting phases of the AMO and IPO,which have been dominant since the advent of satellite observations in *** study utilizes long-term reanalysis data to investigate the impact of four combinations of+AMO+IPO,–AMO–IPO,+AMO–IPO,and–AMO+IPO on Antarctic SAT over the past 115 ***+AMO phase is characterized by a spatial mean temperature amplitude of up to 0.5℃over the North Atlantic Ocean,accompanied by positive sea surface temperature(SST)anomalies in the tropical eastern Pacific and negative SST anomalies in the extratropical-mid-latitude western Pacific,which are indicative of the+IPO *** Antarctic SAT exhibits contrasting spatial patterns during the+AMO+IPO and+AMO–IPO ***,during the–AMO+IPO period,apart from the Antarctic Peninsula and the vicinity of the Weddell Sea,the entire Antarctic region experiences a warming *** most pronounced signal in the SAT anomalies is observed during the austral autumn,whereas the combination of–AMO and–IPO exhibits the smallest magnitude across all the *** wavetrain excited by the SST anomalies associated with the AMO and IPO induces upper-level and surface atmospheric circulation anomalies,which alter the SAT ***,downward longwave radiation anomalies related to anomalous cloud cover play a crucial *** the future,if the phases of AMO and IPO were to reverse(AMO transitioning to a negative phase and IPO transitioning to a positive phase),Antarctica could potentially face more pronounced warming and accelerated melting compared to the current observations.

关键词： Atlantic Multidecadal Oscillation(AMO) Interdecadal Pacific Oscillation(IPO) surface air temperature Antarctic wavetrain Rossby wave source

Modified Biot Elastic Coefficients in Poroelastic Solid

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Journal of Earth Science 2024年第4期35卷 1397-1401页

作者： Chun Yang Yun Wang alexey Stovas Liheng Wang School of Geophysics and Information Technology China University of GeosciencesBeijing100083China Department of Geoscience and Petroleum Norwegian University of Science and TechnologyTrondheim 7031Norway Key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

0 INTRODUCTION Sedimentary rocks predominantly consist of porous solids saturated with fluids,the kinematic and dynamic characteristics of which are described through poroelasticity theory(Biot,1956a,b,1941).The wave propagation in fluid-saturated po-rous rocks obtains extensive attention owing to its relevance in diverse fields,such as ocean acoustics,exploration geophysics,and soil dynamics(Yang et al.,2023a;Xie et al.,2022).

关键词： saturated Elastic a,b

Gradient-induced long-range optical pulling force based on photonic band gap

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Light(Science & Applications) 2024年第5期13卷 865-874页

作者： Wenlong Lu alexey V.Krasavin Sheng Lan Anatoly V.Zayats Qiaofeng Dai Guangdong Basic Research Center of Excellence for Structure and Fundamental Interactions of Matter Guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and DevicesSchool of Information and Optoelectronic Science and EngineeringSouth China Normal UniversityGuangzhou 510006China Department of Physics and London Centre for Nanotechnology King’s College LondonLondon WC2R 2LSUK

Optical pulling provides a new degree of freedom in optical *** is generally believed that long-range optical pulling forces cannot be generated by the gradient of the incident ***,we theoretically propose and numerically demonstrate the realization of a long-range optical pulling force stemming from a self-induced gradient field in the manipulated *** analogy to potential barriers in quantum tunnelling,we use a photonic band gap design in order to obtain the intensity gradients inside a manipulated object placed in a photonic crystal waveguide,thereby achieving a pulling *** the usual scattering-type optical pulling forces,the proposed gradient-field approach does not require precise elimination of the reflection from the manipulated *** particular,the Einstein-Laub formalism is applied to design this unconventional gradient *** magnitude of the force can be enhanced by a factor of up to 50 at the optical resonance of the manipulated object in the waveguide,making it insensitive to *** developed approach helps to break the limitation of scattering forces to obtain longrange optical pulling for manipulation and sorting of nanoparticles and other *** developed principle of using the band gap to obtain a pulling force may also be applied to other types of waves,such as acoustic or water waves,which are important for numerous applications.

关键词： optical waveguide scattering

Reconstructing the Absorption Function in a Quasi-Linear Sorption Dynamic Model via an Iterative Regularizing Algorithm

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Advances in Applied Mathematics and Mechanics 2024年第1期16卷 237-252页

作者： alexey Shcheglov Jingzhi Li Chao Wang Alexander Ilin Ye Zhang Faculty of Computational Mathematics and Cybernetics Shenzhen MSU-BIT UniversityShenzhenGuangdong 518172China Faculty of Computational Mathematics and Cybernetics Lomonosov Moscow State UniversityMoscowRussia Department of Mathematics&National Center for Applied Mathematics Shenzhen&SUSTech International Center for Mathematics Southern University of Science and TechnologyShenzhenGuangdong 518055China School of Mathematics and Statistics Beijing Institute of TechnologyBeijing 100081China

This study addresses the parameter identification problem in a system of time-dependent quasi-linear partial differential equations(PDEs).Using the integral equation method,we prove the uniqueness of the inverse problem in nonlinear ***,using the method of successive approximations,we develop a novel iterative algorithm to estimate sorption *** stability results of the algorithm are proven under both a priori and a posteriori stopping rules.A numerical example is given to show the efficiency and robustness of the proposed new approach.

关键词： Inverse problem quasi-linear dynamic model uniqueness method of successive approximations stability

Development and evaluation of a vision driven sensor for estimating fuel feeding rates in combustion and gasification processes

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Energy and AI 2024年第1期15卷 44-54页

作者： YngveÖren alexey Sepman Ehsan Fooladgar Fredrik Weiland Henrik Wiinikka RISE AB Box 726 SE-94128PiteåSweden Energy Engineering Division of Energy ScienceLuleåUniversity of TechnologySE 97187LuleåSweden

A machine vision driven sensor for estimating the instantaneous feeding rate of pelletized fuels was developed and tested experimentally in combustion and gasification *** feeding rate was determined from images of the pellets sliding on a transfer chute into the *** the images the apparent area and velocity of the pellets were *** was determined by a segmentation model created using a machine learning framework and velocities by image registration of two subsequent *** measured weight of the pelletized fuel passed through the feeding system was in good agreement with the weight estimated by the *** observed variations in the fuel feeding correlated with the variations in the gaseous species concentrations measured in the reactor core and in the *** the developed sensor measures the ingoing fuel feeding rate prior to the reactor,its signal could therefore help improve process control.

关键词： Fuel feeding Process monitoring Image processing Neural network Combustion Gasification