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Chinese Physics B 2024年第10期33卷 153-158页

作者： Long-quan Lai Zhao li School of Science Nanjing University of Posts and TelecommunicationsNanjing 210023China School of Electronic Engineering Chengdu Technological UniversityChengdu 611730China

Emission of matter-wave jets from a parametrically driven condensate has attracted significant experimental and theoretical attention due to the appealing visual effects and potential metrological *** this work,we investigate the collective particle emission from a Bose-Einstein condensate confined in a one-dimensional lattice with periodically modulated interparticle *** give the regimes for discrete modes,and find that the emission can be distinctly *** configuration induces a broad band,but few particles are ejected due to the interference of the matter *** further qualitatively model the emission process and demonstrate the short-time *** engineering provides a way to manipulate the propagation of particles and the corresponding dynamics of condensates in lattices,and may find application in the dynamical excitation control of other nonequilibrium problems with time-periodic driving.

关键词： Bose-Einstein condensate matter-wave jet periodic modulation

liouville type theorems for Schrdinger systems

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Science China Mathematics 2015年第1期58卷 179-196页

作者： ZHUO Ran li Feng quan Department of Mathematical Sciences Yeshiva University School of Mathematical Sciences Dalian University of Technology

We study positive solutions to the following higher order SchrSdinger system with Dirichlet boundary conditions on a half space： where a is any even number between 0 and n. This PDE system is closely related to the integral system where G is the corresponding Green＇s function on the half space. More precisely, we show that every solution to （0.2） satisfies （0.1）, and we believe that the converse is also true. We establish a liouville type theorem the non-existence of positive solutions to （0.2） under a very weak condition that u and v are only locally integrable. Some new ideas are involved in the proof, which can be applied to a system of more equations.

关键词： Schrodinger systems poly-harmonic operators Dirichlet boundary conditions method of movingplanes in integral forms Kelvin transforms monotonicity rotational symmetry non-existence

Lymphopenia predicts disease severity of COVID-19:a descriptive and predictive study

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Signal Transduction and Targeted Therapy 2020年第1期5卷 2129-2131页

作者： li Tan Qi Wang Duanyang Zhang Jinya Ding Qianchuan Huang Yi-quan Tang Qiongshu Wang Hongming miao Department of Disease Control and Prevention General Hospital of Central Theater Command430015 WuhanHubei provincePeople’s Republic of China Department of Laboratory General Hospital of Central Theater Command430015 WuhanHubei provincePeople’s Republic of China MRC Laboratory of Molecular Biology Cambridge Biomedical CampusCambridge CB20QHUK Department of Biochemistry and Molecular Biology Third Military Medical University(Army Medical University)400038 ChongqingPeople’s Republic of China

Dear Editor,An outbreak of an unknown infectious pneumonia has recently occurred in Wuhan,China.1 The pathogen of the disease was quickly identified as a novel coronavirus(SARS-CoV-2,severe acute respiratory syndrome coronavirus 2),and the disease was named coronavirus disease-19(COVID-19).2 The virus has so far caused 78,959 confirmed cases and 2791 deaths in China according to the reports of ***-19 has been spreading in many countries such as Japan,Korea,Singapore,Iran,and Italia.

关键词： severity acute Lymph

Data and Machine Learning in Polymer Science

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维普期刊数据库

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Chinese Journal of Polymer Science 2023年第9期41卷 1371-1376,I0006页

作者： Yun-Qi li Ying Jiang li-quan Wang Jian-Feng li Department of Polymer Materials and Engineering College of Materials and MetallurgyGuizhou UniversityGuiyang550025China School of Chemistry Beihang UniversityBeijing100191China Shanghai Key Laboratory of Advanced Polymeric Materials School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai200237China The State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai200433China

Data-driven innovation has shown great power in solving problems in multifactor correlation,convergence and optimization,synergistic and antagonistic effects,pattern and boundary identification,critical behavior and phase transition,which are ubiquitous in polymer *** for the in-depth understanding of physical problems or in the discovery of new polymer materials,integrating data and machine learning into conventional experimental,theoritical,modeling and simulation approaches becomes *** we present a perspective based on our research interests,highlight some key issues and provide a prospection in this emerging *** focus on a number of typical advances in the description and identification of polymer conformation and structures,and the interpretation and prediction of structureproperty correlations,that have applied data and machine learning in polymer science.

关键词： Machine learning Big data Structure-property relationship Optimization Prediction

Emerging energy chemistry in lithium-sulfur pouch cells

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Science China Chemistry 2021年第3期64卷 337-338页

作者： Bo-quan li Qiang Zhang Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

On pursuing high-energy-density energy storage systems beyond the current lithium-ion battery technique, lithium-sulfur(li-S) batteries have attracted worldwide attention due to their ultrahigh theoretical energy density up to 500 Wh kg-1[1]. The unique li-S chemistry based on the conversion reactions between solid sulfur, dissolved lithium polysulfides, and solid lithium sulfide affords thermodynamic advantages including high cathode specific capacity and low anode potential [2].

关键词： battery lithium energy

Annealing Embrittlement in Fe-Mo-Si-B Amorphous Alloy

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Journal of Materials Science & Technology 1997年第1期13卷 61-64页

作者： li, JM quan, MX Hu, ZQ National Key Lab. of RSA Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

Annealing at T-a=200 degrees C or so, the enhancement in the average tensile fracture strength of as-quenched (Fe0.99Mo0.01)(78)Si9B13 metallic glass increases about 7 similar to 8%. The origin of the annealing embrittlement at 244 degrees C in the metallic glass (Fe0.99Mo0.01)(78)Si9B13 was revealed that due to the formation of nanoscale granular with bcc structure resulting in the stress localization. The temperature of annealing embrittlement was in agreement with the calculated value from T-bcc=0.637 T-c (T-c is the crystallized temperature), based on micromechanism of crystallization of metallic glass.

关键词： Metallic glass

Optimization of Output Properties for Bias Signal-Modulated in a Single-Mode Laser

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Communications in Theoretical Physics 2005年第2X期44卷 288-292页

作者： li Tai-quan DONG Ping YANG Hong-quan HAN li-Bo School of Physical Science and Technology Yangtze University Jingzhou 434020 China

Defining the quantity K as the signal-to-noise ratio （SNR） and the normalized intensity fluctuation C（O） of a single-mode laser for bias signal modulation driven by color noises with colored correlation, the whole output properties of the laser system is described by K. It is found that there is a maximum in the curves of K versus D, Q, and io. The optimization parameters are gained.

关键词： bias signal modulation correlation noise optimization

A Pohozaev Identity for the Fractional Hnon System

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Acta Mathematica Sinica,English Series 2017年第10期33卷 1382-1396页

作者： Pei MA Feng quan li Yan li Institute of Mathematics School of Mathematical Sciences Nanjing Normal University Nanjing 210023 P. R. China Department of Mathematical Sciences Yeshiva University New York NY 10033 USA School of Mathematical Sciences Dalian University of Technology Dalian 116024 P. R. China

In this paper, we study the Pohozaev identity associated with a Henon-Lane-Emden sys- tem involving the fractional Laplacian：{（-△）^su=｜x｜^aυ^p,x ∈Ω,（-△）^sυ=｜x｜^av^p,x ∈Ω u=υ=0, x∈R^b／Ω,in a star-shaped and bounded domain Ω for s E （0, 1）. As an application of our identity, we deduce the nonexistence of positive solutions in the critical and supercritieal cases.

关键词： Pohozaev identity fractional Laplacian Henon system nonexistence of solutions

Constitutive model of viscoelastic dynamic damage for the material of gas obturator in modular-charge howitzer

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Defence Technology（防务技术） 2024年第9期39卷 203-216页

作者： Zhonggang li Longmiao Chen Yifan li Yufeng Jia quan Zhang School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China Technology Center Shanxi North Machine-building Co.Ltd.Taiyuan 030009China Research and Development Department Kelong New Material Technology Co.Ltd.Xianyang 712000China

In order to investigate the mechanical response behavior of the gas obturator of the breech mechanism,made of polychloroprene rubber(PCR), uniaxial compression experiments were carried out by using a universal testing machine and a split Hopkinson pressure bar(SHPB), obtaining stress-strain responses at different temperatures and strain rates. The results revealed that, in comparison to other polymers, the gas obturator material exhibited inconspicuous strain softening and hardening effects;meanwhile, the mechanical response was more affected by the strain rate than by temperature. Subsequently, a succinct viscoelastic damage constitutive model was developed based on the ZWT model, including ten undetermined parameters, formulated with incorporating three parallel components to capture the viscoelastic response at high strain rate and further enhanced by integrating a three-parameter Weibull function to describe the damage. Compared to the ZWT model, the modified model could effectively describe the mechanical response behavior of the gas obturator material at high strain rates. This research laid a theoretical foundation for further investigation into the influence of chamber sealing issues on artillery firing.

关键词： Breech mechanism Gas obturator Polychloroprene rubber Constitutive model Strain rate Damage

Effect of Eliminating Edges on Robustness of Scale-Free Networks under Intentional Attack

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Chinese Physics Letters 2010年第6期27卷 270-272页

作者： li Yong WU Jun ZOU An-quan Department of Business Administration Changsha University Changsha 410073 College of Information Systems and Management National University of Defense Technology Changsha 410073

We study the robustness of complex networks under edge elimination. We propose three different edge elimination strategies and investigate their effects on the robustness of scale-free networks under intentional attack. We show that deleting a proper fraction of edges connecting hub nodes and hub nodes can enhance the robustness of scale-free networks under intentional attack.

关键词： Scales Nodes