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Journal of Hydrodynamics 2021年第3期33卷 468-478页

作者： ming-Xin Li Zhi-ming Yuan Longbin Tao Department of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang212008China Department of Naval Architecture Ocean and Marine EngineeringUniversity of StrathclydeGlasgowUK

An iterative time-marching scheme is developed to investigate the hydrodynamic interactions between multiple *** an unsteady interactive effect could be magnified in restricted waterways,e.g.,a channel or harbor *** the author’s knowledge,nearly all the research on the ship-to-ship interaction neglecting the free surface *** free surface is usually treated as a rigid *** assumption is only reasonable when the speed of the ships is very low in deep water condition,due to the hydrodynamic interaction between the ships is mainly induced by near-field ***,when the moving speeds are moderately higher,especially with a small lateral separation between ships,the far-field effects arising from the ship waves become *** main objective of the present paper is to develop an iterative time-matching algorithm to solve the hydrodynamic interaction between high-speed ships taking into account the nonlinear free surface boundary condition in time domain.

关键词： Iterative time-marching scheme hydrodynamic interaction multi-ships free surface

Homogeneous Finsler spaces with only one orbit of prime closed geodesics

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Science China Mathematics 2020年第11期63卷 2321-2342页

作者： ming Xu School of Mathematical Sciences Capital Normal UniversityBeijing 100048China

When a closed Finsler manifold admits continuous isometric actions,estimating the number of orbits of prime closed geodesics seems a more reasonable substitution for estimating the number of prime closed *** extend the results of Duan,Long,Rademacher,Wang and others on the existence of two prime closed geodesics to the equivariant situation,we propose the question if a closed Finsler manifold has only one orbit of prime closed geodesics if and only if it is a compact rank-one Riemannian symmetric *** this paper,we study this problem in homogeneous Finsler geometry,and get a positive answer when the dimension is even or the metric is *** guess the rank inequality and the algebraic techniques in this paper may continue to play an important role for discussing our question in the non-homogeneous situation.

关键词： homogeneous Finsler space closed geodesic compact rank-one symmetric space connected isometry group Killing vector field

Multiparty semiquantum key agreement without entanglement

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Communications in Theoretical Physics 2020年第6期72卷 70-75页

作者： ming-ming Wang Rui-Fan Han Lin-ming Gong Shaanxi Key Laboratory of Clothing Intelligence State and Local Joint Engineering Research Center for Advanced Networking and Intelligent Information ServicesSchool of Computer ScienceXi'an Polytechnic UniversityXi'an 710048China

The key agreement protocols allow two or more users to negotiate a shared key for establishing a secure communication channel without a third trusted party in such a way that the shared key is determined by all authorized players rather than any subset of *** propose the first real multiparty semiquantum key agreement(SQKA)protocols based on *** protocols include only one quantum player,while the others are classical players who only need to measure and prepare states in the classical *** first present a symmetric three-party SQKA protocol,where two classical players can fairly negotiate a key with a quantum player by using single-photons as message *** we present an asymmetric SQKA protocol where a relatively low percentage of quantum states are used for eavesdropping *** we further extend them to an asymmetric multiparty SQKA *** SQKA protocols require fewer quantum resources than the previous SQKA protocols for classical players,especially without requirement of entanglement,which makes them easier to implement using current *** protocols are secure against external eavesdroppers and are fair against a minority of internal dishonest players.

关键词： multiparty semiquantum key agreement single-photon fairness efficiency symmetric and asymmetric protocol

Microscratch of copper by a Rockwell C diamond indenter under a constant load

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Nanotechnology and Precision Engineering 2021年第3期4卷 20-44页

作者： ming Liu School of Mechanical Engineering and Automation Fuzhou UniversityQishan CampusFuzhou 350116China

The scratch test is used for quality control mostly in phenomenological ways,and whether fracture toughness can be obtained from this test is still a matter of debate requiring further *** this paper,values of the fracture toughness of copper obtained by different scratch-based approaches are compared in order to examine the applicability of scratch-based methodologies to characterize the fracture toughness of soft *** scratch response of copper to a Rockwell C diamond indenter is studied under a constant normal load *** variations of penetration depth,residual depth,and residual scratch width with applied normal load are quantified from spherical to sphero-conical contact regimes by piecewise functions.A newly proposed size effect law is found to be the most suitable for scratch-based approaches to characterizing the fracture toughness of soft metallic materials with significant plasticity.A simple expression relating the nominal stress to the penetration depth is proposed for the spherical contact regime and gives almost the same value of fracture *** residual scratch width provides useful information on pile-up of material and on the spherical tip radius of the *** is found that the values of the fracture toughness obtained from the microscratch test are influenced by the data range for analysis.

关键词： Microscratching Rockwell C diamond probe Constant normal load Fracture toughness Residual scratch width

Lateral habenula neurocircuits mediate the maternal disruptive effect of maternal stress: A hypothesis

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Zoological Research 2022年第2期43卷 166-175页

作者： ming Li Department of Psychology University of Nebraska-LincolnLincolnNE 68588USA

Up to 20%of women experience stress-related disorders during the postpartum period;however,little is known about the specific neural circuitry by which maternal stress exerts its negative impacts on mental health and maternal caregiving ***,such a circuitry should serve as an interface between the stress response system and maternal neural network,transmitting stress signals to the neural circuitry that mediates maternal *** this paper,I propose that the lateral habenula(LHb)serves this interface *** shows that the LHb plays a key role in encoding stress-induced effects and in the pathophysiology of major depression and stressrelated anxiety,and thus may play a role in maternal behavior as part of the maternal brain network.I hypothesize that maternal stress acts upon the LHb and two of its major downstream targets,i.e.,ventral tegmental area(VTA)and dorsal raphe nucleus(DRN),compromising the maternal care and contributing to postpartum mental *** hypothesis makes three predictions:(1)maternal stress enhances LHb neuronal activity;(2)activation of DRN-and VTA-projecting neurons in the LHb mimics the detrimental effects of maternal stress on maternal behavior;and(3)suppression of DRN-and VTA-projecting neurons in the LHb attenuates the detrimental effects of maternal stress on maternal care in stressed *** of this hypothesis is expected to enhance our understanding of the neurocircuit mechanisms mediating stress effects on maternal behavior.

关键词： Maternal behavior Lateral habenula(LHb) Ventral tegmental area Dorsal raphe Maternal stress Postpartum depression Postpartum anxiety

Magnetic reconnection acceleration of astrophysical jets for different jet geometries

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Research in Astronomy and Astrophysics 2015年第4期15卷 475-482页

作者： A-ming Chen Li-ming Rui College of Physical Science and Technology Central China Normal University

The acceleration mechanisms of relativistic jets are of great importance for understanding various astrophysical phenomena such as gamma-ray bursts, active galactic nuclei and microquasars. One of the most popular scenarios is that the jets are initially Poynting-flux dominated and succumb to magnetohydrodynamic instability leading to magnetic reconnections. We suggest that the reconnection timescale and efficiency could strongly depend on the geometry of the jet, which determines the length scale on which the orientations of the field lines change. In contrast to a usually- assumed conical jet, the acceleration of a collimated jet can be found to be more rapid and efficient （i.e. a much more highly saturated Lorentz factor can be reached） while the jets with lateral expansion show the opposite behavior. The shape of the jet could be formed due to the lateral squeezing on the jet by the stellar envelope of a collapsing massive star or the interaction of the jet with stellar winds.

关键词： gamma rays: bursts -- galaxies: jets -- MHD -- instabilities

WIP1 Phosphatase Plays a Critical Neuroprotective Role in Brain Injury Induced by High-Altitude Hypoxic Inflammation

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Neuroscience Bulletin 2017年第3期33卷 292-298页

作者： Dahu Li Lijun Zhang Xin Huang lili Liu Yunling He Lun Xu Yiyao Zhang Tong Zhao Liying Wu Yongqi Zhao Kuiwu Wu Yan Wu ming Fan Lingling Zhu Department of Cognitive Science Institute of Basic MedicalSciencesBeijing 100850China Co-innovation Center of Neuroregeneration Nantong UniversityNantong 226001China Beijing Institute for Brain Disorders Beijing 100069China Navy General Hospital of the PLA Beijing 100048China Air Force General Hospital of the PLA Beijing 100142China

The hypobaric hypoxic environment in highaltitude areas often aggravates the severity of inflammation and induces brain injury as a consequence. However, the critical genes regulating this process remain largely unknown. The phosphatase wild-type p53-induced phosphatase 1（WIP1） plays important roles in various physiological and pathological processes, including the regulation of inflammation in normoxia, but its functions in hypoxic inflammation-induced brain injury remain ***, we established a mouse model of this type of injury and found that WIP1 deficiency augmented the release of inflammatory cytokines in the peripheral circulation and brain tissue, increased the numbers of activated microglia/macrophages in the brain, aggravated cerebral histological lesions, and exacerbated the impairment of motor and cognitive abilities. Collectively, these results provide the first in vivo evidence that WIP1 is a critical neuroprotector against hypoxic inflammation-induced brain injury.

关键词： Hypobaric hypoxia Inflammation Brain injury WIP1 phosphatase Lipopolysaccharide

Bulk preparation of free-standing single-iron-atom catalysts directly as the air electrodes for high-performance zinc-air batteries

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Carbon Energy 2023年第5期5卷 57-66页

作者： Hong-Bo Zhang Yu Meng Hong Zhong lili Zhang Shichao Ding Lingzhe Fang Tao Li Yi Mei Peng-Xiang Hou Chang Liu Scott P.Beckman Yuehe Lin Hui-ming Cheng Jin-Cheng Li Yunnan Provincial Key Laboratory of Energy Saving in Phosphorus Chemical Engineering and New Phosphorus Materials Faculty of Chemical EngineeringKunming University of Science and TechnologyKunmingChina Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyangChina School of Mechanical and Materials Engineering Washington State UniversityPullmanWashingtonUSA Department of Chemistry and Biochemistry Northern Illinois UniversityDeKalbIllinoisUSA Argonne National Laboratory X-Ray Science DivisionLemontIllinoisUSA

The keen interest in fuel cells and metal-air batteries stimulates a great deal of research on the development of a cost-efficient and high-performance catalyst as an alternative to traditional Pt to boost the sluggish oxygen reduction reaction(ORR)at the ***,we report a facile and scalable strategy for the large-scale preparation of a free-standing and flexible porous atomically dispersed Fe-N-doped carbon microtube(FeSAC/PCMT)*** from its unique structure that greatly facilitates the catalytic kinetics,mass transport,and electron transfer,our FeSAC/PCMT electrode exhibits excellent performance with an ORR potential of 0.942 V at^(-3) mA cm^(-2).When the FeSAC/PCMT sponge was directly used as an oxygen electrode for liquid-state and flexible solid-state zinc-air batteries,high peak power densities of 183.1 and 58.0 mW cm^(-2) were respectively achieved,better than its powdery counterpart and commercial Pt/C *** and theoretical investigation results demonstrate that such ultrahigh ORR performance can be attributed to atomically dispersed Fe-N_(5) species in FeSAC/*** study presents a cost-effective and scalable strategy for the fabrication of highly efficient and flexible oxygen electrodes,provides a significant new insight into the catalytic mechanisms,and helps to realize significant advances in energy devices.

关键词： atomic Fe-N_(5)species free-standing electrode large-scale preparation oxygen reduction reaction zinc-air battery

Effect of cold rolling and annealing on microstructure and properties of a new resource-saving duplex stainless steel Fe–19Cr–0.6Al–12Mn

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Journal of Iron and Steel Research International 2020年第12期27卷 1420-1432页

作者： ming-ming Pan Xiao-ming Zhang Yong Chen Xiang-bin Su Peng Chen State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina

An Fe-19Cr-0.6Al-12Mn duplex stainless steel with an optimized alloy composition of Ni replaced by Mn and Cr partially replaced by Al was developed to avoid the edge cracking, which is a common defect in the hot rolling of traditional twophase stainless steels. The newly developed duplex stainless steel could be hot-rolled in the single-phase ferrite (α) region by controlling rolling temperature and the single-phase ferrite microstructure was retained on water cooling. To obtain the two-phase stainless steel product with ferrite and austenite (γ) microstructure, cold rolling and annealing were carried out,and appropriate cold rolling reduction and annealing process parameters were determined. The significant impact of annealing on microstructure, mechanical properties and pitting resistance of the experimental steel was studied. It was observed that with the increase in cold rolling reduction, the number of γ nucleation points was dramatically increased leading to the precipitation of more γ at α grain boundaries after annealing. During annealing at 800 ℃ and with the increase in annealing time, the austenite fraction was increased with a lower rate and remained almost constant when the annealing time was greater than 4 h. With the increase in annealing temperature, the austenite fraction decreased gradually in the temperature range of 750-860 ℃. Good combination of strength, ductility and excellent pitting resistance was obtained by cold rolling to 80% reduction and annealing at 800 ℃ for 4 h. Grain refinement and the existence of Σ3 boundaries played a vital role in improving the pitting resistance of the experimental steel. With good combination of strength, ductility and corrosion resistance, the newly developed duplex stainless steel is expected to be a new resource-saving dual-phase stainless steel.

关键词： Resource-saving duplex stainless steel Edge cracking Rolling reduction Annealing Tensile property Pitting corrosion

Long-term field measurement and analysis of the natural wind characteristics at the site of Xi-hou-men Bridge

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第3期13卷 197-207页

作者： ming LIU Hai-li LIAO ming-shui LI Cun-ming MA Mei YU Research Center for Wind Engineering Southwest Jiaotong University Chengdu 610031 China Chongqing Jiaotong University Chongqing 400074 China

In order to investigate the wind characteristics of coastal areas of China, a long-term field measurement of natural wind was carried out. Based on the field measurement results, this paper presents the natural wind characteristics of typhoons and strong monsoons at the site of Xi-hou-men Bridge, including mean wind speed, mean wind direction, mean wind elevation angle, turbulent intensity, gust factor, turbulence integral length scales, power spectrum of wind speed and spatial correlation of gusty wind, the profiles of mean wind speed and turbulent intensity, etc. The correlation among wind characteristics is analyzed in detail, and the similarities and differences of wind characteristics between typhoons and monsoons are analyzed. These results can pro- vide detailed wind characteristics of coastal areas of China.

关键词： Wind characteristics Field measurement Wind spectrum Wind profiles Spatial correlation