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Impact damage testing based on high-speed continuous water jet aircraft coatings

Chinese Journal of Aeronautics 2024年第10期37卷 249-264页

作者： Minggong SHA Ying SUN Yutong LI Yiming LIU Gregory FEDOTENKOV Lev RABINSKIY Arseniy BABAYTSEV Yulong LI School of Civil Aviation Northwestern Polytechnical UniversityXi’an 710072China Joint International research Laboratory of Impact Dynamics and Engineering Application Xi’an 710072China Shaanxi Impact Dynamics and Engineering Application Laboratory Xi’an 710072China NPU Yangzi River Delta research Institute Suzhou 215400China Moscow Aviation Institute(National research University) Moscow 125993Russia

When an aircraft passes through a rainy area at high speed,the coating on the front edge of the fuselage will be continuously eroded by raindrops,causing the coating to wear,crack or even peel *** paper uses carbon fiber T300 material as the base material,and at the different impact speeds and impact numbers,water cutting equipment was used to simulate the erosion of the coating caused by the continuous impact of water *** damage morphology of samples at different damage stages was observed by digital microscope and Scanning Electron Microscope(SEM),and the damage evolution curve was established to analyze and reveal the damage behavior and damage mechanism of rain *** results show that the degree of damage experienced an increasing trend with the increase of impact numbers and speed,until circular peel damage was formed;no damage occurred during the incubation period,and the curvature of the damage evolution curve increased significantly after the expansion period and eventually showed a stable expansion *** mechanical properties of the coating material were the main influencing factors of its rain corrosion ***,the axially symmetric unsteady contact problem of droplets impacting the surface of a solid deformable body was *** the contact area was determined based on the iterative algorithm boundary positioning method.A mathematical model and closed mathematical formula describing the unsteady interaction between a droplet and a solid deformable obstacle were proposed.

关键词： Rain erosion damage Liquid-solid impact Multiple jets Composite materials Impact dynamics

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Collision-avoidance strategy for a spinning electrodynamic tether system

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Astrodynamics 2024年第2期8卷 247-259页

作者： Linxiao Li Aijun Li Hongshi Lu Changqing Wang Yuriy Mikhailovich Zabolotnov Yong Guo School of Automation Northwestern Polytechnical UniversityXi’an 710129China Institute of IT and Cybernatics Samara National Research UniversitySamara 443086Russia

Spinning electrodynamic tether systems(SEDTs)have promising potential for the active removal of space debris,the construction of observation platforms,and the formation of artificial ***,owing to the survivability problem of long tethers,designing collision-avoidance strategies for SEDTs with space debris is an urgent *** study focuses on the design of collision-avoidance strategies for SEDTs with an electrodynamic force(Ampere force).The relative distance between the debris and the SEDT is first derived,and then two collision-avoidance strategies are proposed according to the two different *** debris collides closer to a lighter subsatellite,a stationary avoidance strategy is proposed to change the spatial position of the subsatellite by adjusting only the angular motion of the tether,which maintains the original orbit of the *** debris collides closer to a heavier main spacecraft,a comprehensive avoidance strategy is proposed to change the spatial position of the SEDT by slightly modifying the orbital height and changing the tether angular motion *** numerical results illustrate that the proposed strategies promptly avoid potential collisions of an SEDT with space debris without significant changes in the orbital parameters of the SEDT.

关键词： spinning electrodynamic tether systems(SEDTs) collision analysis collision avoidance

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Age and geochemical evolution of granite magmatism in Olkhon region from Caledonian syncollisional ore-free granite to the rare metal granite and pegmatite of Middle Paleozoic intraplate setting

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China Geology 2024年第1期7卷 63-79页

作者： Viktor Antipin Valentina Makrygina Larisa Kushch Nataliya Sheptyakova Vinogradov Institute of Geochemistry SB RAS664033 IrkutskRussia

The detailed description of two granite complexes in the Olkhon subterrane is *** Early Paleozoic Sharanur complex was formed by granitization of gneisses of the Olkhon *** includes migmatites,granite-gneisses,granites and pegmatites of normal alkalinity;they belong to the type of syncollisional *** Middle Paleozoic Aya granite complex includes mother Aya massif of amazonite-bearing granites and several types of rare-metal *** have elevated alkalinity,low of Ba,Sr,and high LILE and HFSE elements *** Aya pegmatites lie in northwest cracks of stretching and associated with the rise of the territory under the influence of the North Asian *** cracks and pegmatites mark the beginning of a new intraplate geodynamic *** geochemical types are distinguished among the pegmatites of this *** are amazonite pegmatites of Li-F type with Ta mineralization and complex type pegmatite with Be-Rb-Nb-Ta and Li-F mineralization(the Ilixin vein).The Tashkiney pegmatite vein is similar to Ilixin,but lies in the gneisses of the Olkhon *** shows high concentrations of Be,Nb,Ta,as well as W,Sn,but lacks Li and F,due to a greater depth and higher temperature of the melt crystallization of this pegmatite.

关键词： Pegmatite Geochemistry Submantle plume Magmatism Caledonian collision Middle Paleozoic intraplate setting Be-Rb-Nb-Ta-Li-F mineralization Olkhon region Russia

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Intertype superconductivity evoked by the interplay of disorder and multiple bands

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Frontiers of physics 2024年第4期19卷 81-89页

作者： P.M.Marychev A.A.Shanenko A.V.Vagov HSE University 101000 MoscowRussia Center for Advanced Mesoscience and Nanotechnology MIPTDolgoprudny141700Russia

Nonmagnetic impurity scattering is known to shift up the Ginzburg-Landau parameter k of a *** this case,when the system is initially in type I,it can change its magnetic response,crossing the intertype domain with k~1 between the two standard superconductivity types and arriving at type *** the present work we demonstrate that the impact of disorder can be much more profound in the presence of the multiband structure of the charge carrier *** particular,when the band diffusivities differ from each other,the intertype domain tends to expand significantly,including points with k>>1 that belong to deep type-Ⅱ in conventional single-band *** finding sheds light on the nontrivial disorder effect and significantly complements earlier results on the enlargement of the intertype domain in clean multiband superconductors.

关键词： superconductivity disorder intertype superconductivity twoband model

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Moderate Fields, Maximum Potential: Achieving High Records with Temperature‑Stable Energy Storage in Lead‑Free BNT‑Based Ceramics

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Nano-Micro Letters 2024年第5期16卷 184-200页

作者： Wenjing Shi Leiyang Zhang Ruiyi Jing Yunyao Huang Fukang Chen Vladimir Shur Xiaoyong Wei Gang Liu Hongliang Du Li Jin Electronic Materials research Laboratory Key Laboratory of the Ministry of EducationSchool of Electronic Science and EngineeringXi’an Jiaotong UniversityXi’an 710049People’s Republic of China School of Materials and Energy Southwest UniversityChongqing 400715People’s Republic of China School of Natural Sciences and Mathematics Ural Federal UniversityEkaterinburg 620000Russia Multifunctional Electronic Ceramics Laboratory College of EngineeringXi’an International UniversityXi’an 710077People’s Republic of China

The increasing awareness of environmental concerns has prompted a surge in the exploration of leadfree,high-power ceramic *** efforts to develop leadfree dielectric ceramics with exceptional energystorage performance(ESP)have predominantly relied on multicomponent composite strategies,often accomplished under ultrahigh electric ***,this approach poses challenges in insulation and system downsizing due to the necessary working voltage under such *** extensive study,bulk ceramics of(Bi_(0.5)Na_(0.5))TiO_(3)(BNT),a prominent lead-free dielectric ceramic family,have seldom achieved a recoverable energy-storage(ES)density(Wrec)exceeding 7 J cm^(−3).This study introduces a novel approach to attain ceramic capacitors with high ESP under moderate electric fields by regulating permittivity based on a linear dielectric model,enhancing insulation quality,and engineering domain structures through chemical formula *** incorporation of SrTiO_(3)(ST)into the BNT matrix is revealed to reduce the dielectric constant,while the addition of Bi(Mg_(2/3)Nb_(1/3))O_(3)(BMN)aids in maintaining ***,the study elucidates the methodology to achieve high ESP at moderate electric fields ranging from 300 to 500 kV cm^(−1).In our optimized composition,0.5(Bi_(0.5)Na_(0.4)K_(0.1))TiO_(3)–0.5(2/3ST-1/3BMN)(B-0.5SB)ceramics,we achieved a Wrec of 7.19 J cm^(−3) with an efficiency of 93.8%at 460 kV cm^(−1).Impressively,the B-0.5SB ceramics exhibit remarkable thermal stability between 30 and 140℃ under 365 kV cm^(−1),maintaining a Wrec exceeding 5 J cm^(−3).This study not only establishes the B-0.5SB ceramics as promising candidates for ES materials but also demonstrates the feasibility of optimizing ESP by modifying the dielectric constant under specific electric field ***,it provides valuable insights for the future design of ceramic capacitors with high ESP under constraints of limited electric field.

关键词： BNT Energy storage Lead-free Relaxor ferroelectrics Capacitors

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Dreicer Electric Field Definition and Runaway Electrons in Solar Flares

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research in Astronomy and Astrophysics 2024年第2期24卷 180-184页

作者： Yu.T.Tsap A.V.Stepanov Yu.G.Kopylova Crimean Astrophysical Observatory of the russian Academy of Sciences Nauchny298409Russia Pulkovo Observatory of the russian Academy of Sciences Pulkovskoje Shosse65/1St.Petersburg196140Russia

We analyze electron acceleration by a large-scale electric field E in a collisional hydrogen plasma under the solar flare coronal conditions based on approaches proposed by Dreicer and Spitzer for the dynamic friction force of *** Dreicer electric field EDr is determined as a critical electric field at which the entire electron population runs *** regimes of strong(E≲E_(Dr))and weak(E≪E_(Dr))electric field are *** is shown that the commonly used formal definition of the Dreicer field leads to an overestimation of its value by about five *** critical velocity at which the electrons of the"tail"of the Maxwell distribution become runaway under the action of the sub-Dreiser electric fields turns out to be underestimated by√3 times in some works because the Coulomb collisions between runaway and thermal electrons are not taken into *** electron acceleration by sub-Dreicer electric fields generated in the solar corona faces difficulties.

关键词： acceleration of particles-Sun flares-Physical Data and Processes

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基于CT图像三维重建的高温下再生混凝土孔隙特征研究

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材料导报 2024年第5期38卷 214-224页

作者：都思哲张淼张玉 Selyutina Nina Smirnov Ivan 马树娟董晓强刘元珍太原理工大学土木工程学院太原030024 Coronation Property Co.Pty Ltd/MN Builders 新南威尔士州2620 圣彼得堡国立大学圣彼得堡190000

高温会导致混凝土微细观结构损伤劣化,进而导致混凝土力学性能下降。本工作利用计算机层析成像(CT)技术对高温后掺加玻化微珠的再生混凝土(Recycled aggregate concrete mixed with glazed hollow beads, GHB-RAC)试件孔隙结构特征进行... 详细信息

高温会导致混凝土微细观结构损伤劣化,进而导致混凝土力学性能下降。本工作利用计算机层析成像(CT)技术对高温后掺加玻化微珠的再生混凝土(Recycled aggregate concrete mixed with glazed hollow beads, GHB-RAC)试件孔隙结构特征进行识别,基于CT扫描与三维重构建模提取并分析了混凝土孔隙结构的特征参数,同时利用灰色关联理论探究孔隙结构特征参数对混凝土残余抗压强度的影响程度。研究结果表明,温度会影响GHB-RAC内部孔隙结构,内部孔隙孔径及表面积随温度升高而增大,温度的升高也会影响混凝土孔隙均匀性,加剧孔隙不均匀性分布;玻化微珠(Glazed hollow beads, GHB)对混凝土温度传导的阻碍作用明显,GHB的掺入改善了混凝土的孔隙结构,减弱了高温导致的孔隙畸化;孔隙尺寸、孔隙球体度及孔隙表面积与残余抗压强度的灰色关联度均在0.55以上,表明孔隙结构参数与残余抗压强度关联性较好。

关键词： CT扫描再生混凝土孔隙结构抗压强度灰色关联度

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高温后再生保温混凝土损伤劣化数值分析

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太原理工大学学报 2024年第5期55卷 892-904页

作者：刘淑钰苗艳春李明厚李贝贝 SELYUTINA Nina SMIRNOV Ivan 刘元珍张玉太原理工大学土木工程学院太原030024 Saint Petersburg State University St.Petersburg 199034Russia

【目的】内部多孔且高温稳定的玻化微珠(glazed hollow beads,GHB)可在一定程度上减缓混凝土的高温损伤劣化,提升混凝土的抗火性能。为了进一步明确GHB改善混凝土抗火性能的机理,从细观尺度出发,提出一种可考虑初始缺陷和再生骨料(recyc... 详细信息

【目的】内部多孔且高温稳定的玻化微珠(glazed hollow beads,GHB)可在一定程度上减缓混凝土的高温损伤劣化,提升混凝土的抗火性能。为了进一步明确GHB改善混凝土抗火性能的机理,从细观尺度出发,提出一种可考虑初始缺陷和再生骨料(recycled coarse aggregate,RCA)取代率的再生保温混凝土(recycled aggregate concrete mixed with glazed hollow beads,RATIC)细观模型的建模方法。【方法】利用现阶段比较常用的塑性损伤模型,探究了RCA取代率(0,50%,100%)、GHB含量(0,70%,100%)和孔隙率(0,2%,4%)对于高温后RATIC力学性能的影响。【结果】结果表明:随着受火温度的提高,荷载作用下RATIC试件的损伤分布均呈现出逐渐加剧的趋势,且500℃后,试件的损伤分布较400℃之前严重。GHB的加入可在一定程度上缓减混凝土内部的损伤劣化,而RCA的加入会加剧此现象。此外,随着孔隙率增大,RATIC试件的强度逐渐变低。

关键词：再生保温混凝土随机骨料模型单轴抗压高温孔隙率

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Resolution and contrast enhancement of laser-scanning multiphoton microscopy using thulium-doped upconversion nanoparticles

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Nano research 2019年第12期12卷 2933-2940页

作者： Alexey B.Kostyuk Artem D.Vorotnov Andrey V.Ivanov Arthur B.Volovetskiy Aleksandr V.Kruglov Lyudmila M.Sencha Liuen Liang Evgenii L.Guryev Vladimir A.Vodeneev Sergey M.Deyev Yiqing Lu Andrei V.Zvyagin Lobachevsky State University of Nizhny Novgorod Nizhny Novgorod 603950Russia Center of Biomedical Engineering Institute of Molecular MedicineSechenov UniversityMoscow 119991Russia ARC Centre of Excellence"Nanoscale BioPhotonics" Department of Physics and AstronomyMacquarie UniversitySydney 2109Australia Institute ofBioorganic Chemistry Russian Academy of SciencesMoscow 117997Russia

High-contrast optical imagi ng is achievable using phosphoresce nt labels to suppress the short-lived background due to the optical backscatterand autofluoresce ***,the long-lived phosphorescence is generally incompatible with high-speed laser-scan ning imaging ***,we show that upc on versi on nan oparticles of structure NaYF4:Yb co-doped with 8%Tm(8T-UCNP)in combi nation with a commerciallaser-scanning multiphoton microscopy are uniquely suited for labeling biological systems to acquire high-resolution images with the enhancedcon *** comparison with many phosphoresce nt labels,the 8T-UCNP emission lifetime of-15μs affords rapid image ***-order optical nonlinearity of the 8T-UCNP(n=4,as confirmed experimentally and theoretically)afforded pushing the resolution limitattain able with UCNPs to the *** contrast enha nceme nt was achieved by suppressing the backgro und using(i)ban dpassspectral filtering of the narrow emission peak of 8T-UCNP at 455-nm,and(ii)time-gating implemented with a time-correlated single-photon counting system that demonstrated the contrast enhancement of>2.5-fold of polyethyle neimine-coated 8T-UCNPs take n up by huma nbreast adeno carcinoma cells *** a result,discrete 8T-UCNP nan oparticles became clearly observable in the freshly excised splee ntissue of laboratory mice 15-min post in trave nous injectio n of an 8T-UCNP *** dem on strated approach paves the way forhigh-contrast,high-resoluti on,and high-speed multiphot on microscopy in challe nging envir onments of i ntense autofluorescence,exogenous staining,and turbidity,as typically occur in intravital imaging.

关键词： upconversion nanoparticles autofluorescence time-gated imaging scanning microscopy time-correlated single photon counting

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Theoretical search for solutions to minimize negative influence of segregation in mixing of particulate solids

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Particuology 2016年第2期14卷 36-41页

作者： Vadim Mizonova Henri Berthiaux Cendrine Gatumel Department of Applied Mathematics lvonovo State Power Engineering University Rabfakovskaya 34 153003 Ivanovo Russia Centre RAPSODEE UMR CNR5 5302 Ecole des Mines d'Albi-Carmaux CampusJarlard route de Teillet 81000 Albi France

The objective of this study is to examine several optimization problems in the batch mixing of segregating particulate solids that can be set up and solved using Markov chain models. To improve the adequacy of such models and exclude some physical contradictions that arise in the linear form, a non-linear Markov chain model for the mixing of segregating components is proposed. Optimal solutions are obtained by controlling the particle flow outside the mixing operating volume while the components are being loaded, modifying particle circulation inside the mixing zone during the process, and by structuring the load in the mixing zone. Solutions are found that not only reduce the negative influence of segregation, but also exclude it altogether. The gain resulting from optimization grows with the rate of segregation. The optimal solutions presented here can be used to improve the design of mixers.

关键词： Mixing Segregation Mixture quality Markov chain Optimization

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