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Exponential Decay in Time of Density of One-dimensional Quantum Navier-Stokes Equations

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Acta Mathematicae Applicatae Sinica 2018年第4期34卷 792-797页

作者： Jian-wei DONG guang-pu lou Jun-hui ZHU Yong YANG School of Mathematics and Physics Zhengzhou University of Aeronautics

The long-time behavior of the particle density of the compressible quantum Navier-Stokes equations in one space dimension is studied. It is shown that the particle density converges exponentially fast to the constant thermal equilibrium state as the time tends to infinity, the decay rate is also obtained. The results hold regardless of either the bigger of the scaled Planck constant or the viscosity constant. This improves the decay results of [5] by removing the crucial assumption that the scaled Planck constant is bigger than the viscosity constant. The proof is based on the entropy dissipation method and the Bresch-Desjardins type of entropy.

关键词： quantum Navier-Stokes equations exponential decay entropy dissipation method

Multiple dynamic bonds enable high mechanical strength and efficient room-temperature self-healable polyurethane for triboelectric nanogenerators

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Science China Chemistry 2025年

作者： Wenwen Zhang Huixia Xuan Xiaofei Xu Jiaming lou Qingbao Guan Zhengwei You State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Institute of Functional Materials College of Materials Science and Engineering Shanghai Key Laboratory of Lightweight Composite Shanghai Engineering Research Center of Nano-Biomaterials and Regenerative Medicine Donghua University

For room temperature self-healing triboelectric nanogenerators（TENGs）, the inherent contradiction between mechanical strength and self-healing properties was an urgent problem to be solved. Based on the phenol-carbamate bond, this paper proposed a strategy to design a new molecular structure and coordinate the triple dynamic bonds, which provided a feasible strategy to solve this contradiction. With polytetramethylene ether glycol（M_n= 1,000） as the soft segment in the main chain of polyurethane（pu）, meanwhile methylene diphenyl diisocyanate and 4,4′-dihydroxybiphenyl（BP） as the hard segment and chain extension agent, respectively, the combination of tetrad benzene ring endowed the resultant 4BP-pu with π-π interaction. The effective reversible dissociation and association with hydrogen bond not only bestowed 4BP-pu with high mechanical strength（16.14 MPa）, but also promoted high self-healing efficiency（94.8%） at room temperature. 4BP-pu was selected as the elastic substrate between polydimethylsiloxane and copper sheet to prepare a self-healing TENG to collect energy from natural ***, the rational molecular structure design provided new ideas for developing self-healing materials and fabricating energy harvest electronics.

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Controlled Radical Polymerization of Styrene in the Presence of Different Copper Complexes and Organic Halides

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Chemical Research in Chinese Universities 1999年第4期15卷 358-363页

作者： CHENG guang-lou HU Chun-pu YING Sheng-kang Laboratory of Living Polymerization East China University of Science and TechnologyShanghai 200237P.R.China

The polymerization behaviors of Styrene (St) in the presence of CuX/L [X=Cl or Br; L= 2,2 bipyridine (bpy), 1,10 phenanthroline (phen) or 4,7 diphenyl 1,10 phenanthroline (DPP) ] and R X (R=trichloromethyl, benzyl or allyl; X=Cl or Br) have been studied and examined. In a CuCl/bpy/RCl/St system, a bimodal GPC peak at the early stage of polymerization was observed, and a concept of multi active species was proposed to explain this phenomenon. In a CuCl/phen (DPP)/RCl/St system, the \%M\%\-n of polystyrene (PS) increased linearly with St conversion and ln[M] o/[M] also increased linearly with time, indicating the living nature of this system. Furthermore, the stability of the propagating active species in a CuBr/phen/RBr/St system is higher than that in the CuBr/phen/RBr/St system.

关键词： ATRP 'Living'/controlled radical polymerization 1,10-Phenanthroline 4,7-Diphenyl-1,10-phenanthroline Cuprous halides Styrene

Digital signal acquisition system for complex nuclear reaction experiments

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Nuclear Science and Techniques 2024年第1期35卷 124-133页

作者： Wei-Liang pu Yan-Lin Ye Jian-Ling lou Jia-Hao Chen School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing 100871China Institute of Applied Physics and Computational Mathematics Beijing 100094China

A digital data-acquisition system based on XIA LLC products was used in a complex nuclear reaction experiment using radioactive ion beams.A flexible trigger system based on a field-programmable gate array(FPGA)parametrization was developed to adapt to different experimental sizes.A user-friendly interface was implemented,which allows converting script language expressions into FPGA internal control *** proposed digital system can be combined with a conventional analog data acquisition system to provide more *** performance of the combined system was veri-fied using experimental data.

关键词： Digital signal acquisition system Trigger Programmable logic Timestamp

Product Data Model for Performance-driven Design

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Chinese Journal of Mechanical Engineering 2017年第5期30卷 1112-1122页

作者： guang-Zhong Hu Xin-Jian Xu Shou-Ne Xiao guang-Wu Yang Fan pu School of Mechanical Engineering Sichuan University of Science and Engineering State Key Laboratory of Traction Power Southwest Jiaotong University

When designing large-sized complex machinery products, the design focus is always on the overall per- formance; however, there exist no design theory and method based on performance driven. In view of the defi- ciency of the existing design theory, according to the performance features of complex mechanical products, the performance indices are introduced into the traditional design theory of ＂Requirement-Function-Structure＂ to construct a new five-domain design theory of ＂Client Requirement-Function-Performance-Structure-Design Parameter＂. To support design practice based on this new theory, a product data model is established by using per- formance indices and the mapping relationship between them and the other four domains. When the product data model is applied to high-speed train design and combining the existing research result and relevant standards, the corresponding data model and its structure involving five domains of high-speed trains are established, which can provide technical support for studying the relationships between typical performance indices and design parame- ters and the fast achievement of a high-speed train scheme design. The five domains provide a reference for the design specification and evaluation criteria of high speed train and a new idea for the train＇s parameter design.

关键词： Complex product design Performance driven Data model Mapping relationship High-speed train

Multi-Bernoulli Filter for Tracking Multiple Targets Using Sensor Array

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China Ocean Engineering 2020年第2期34卷 245-256页

作者： ZHANG guang-pu ZHENG Ce QIU Long-hao SUN Si-bo Acoustic Science and Technology Laboratory Harbin Engineering UniversityHarbin 150001China College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001China Qindao Haina Underwater Information Technology Co. Ltd.Qindao 266500China

This paper presents a multi-Bernoulli filter for tracking the direction of arrival(DOAs)of time-varying number of targets using sensor *** method operates directly on the measurements of sensor array and does not require any ***,more information is reserved and compared with the after-detection measurements using a finite set of detected *** can significantly improve the tracking performance,especially in low signal-to-noise ***,it inherits the advantages of the multi-Bernoulli approximation which models each of the targets *** allows more accurate multi-target state estimation,especially when targets *** proposed filter does not need clustering step and simulation results showcase the improved performance of the proposed filter.

关键词： multiple target tracking multi-Bernoulli filter direction of arrival estimation random finite set track-before-detect

Microstructural Instability of an Experimental Nickel-Based Single-Crystal Superalloy

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Acta Metallurgica Sinica(English Letters) 2020年第10期33卷 1433-1441页

作者： Bin Yin guang Xie Xiangwei Jiang Shaohua Zhang Wei Zheng Langhong lou Superalloys Division Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China

Microstructural instability with the precipitation of topologically close-packed(TCP)phases of an experimental nickel-based single-crystal superalloy has been investigated.A significant amount of σ phases are distinguished in the interdendritic region of the as-cast samples after thermal exposure at 900℃ for 1000 ***σphases are preferentially precipitated at the periphery of coarse γ/γ′eutectic,and their morphological evolution from needles to granules is *** analysis suggests that the local segregation of Cr and Ti at the periphery of coarse γ/γ′eutectic accounts for the formation ofσphases in the as-cast *** heat treatment with low solution temperature and short holding time,the dendritic segregation of alloying elements(i.e.,W,Re,Ti and Ta)and the volume fraction of γ′phase in the interdendritic region are similar to that of the as-cast ***,no TCP phases are present in the interdendritic region of the heat-treated samples after thermal exposure,which is primarily ascribed to the elimination of local segregation of Cr and Ti near the coarse γ/γ′***,small quantities ofμphases are precipitated in the secondary dendrite arm near the interdendritic region after thermal exposure,due to the increased volume fraction ofγ′phase and the concomitant enrichment of W and Re in theγmatrix.

关键词： Nickel-based single-crystal superalloy Topologically close-packed(TCP)phases Segregation Eutectic

The primary use of artificial intelligence in cardiovascular diseases: what kind of potential role does artificial intelligence play in future medicine?

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Journal of Geriatric Cardiology 2019年第8期16卷 585-591页

作者： Yang YAN Jia-Wen ZHANG guang-Yao ZANG Jun pu Department of Cardiology Ren Ji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghaiChina Department of Dermatology the First Affiliated Hospital of Nanjing Medical UniversityNanjingJiangsuChina School of Medicine Jiangsu UniversityZhenjiangJiangsuChina

Cardiovascular diseases (CVD) is a major threat to human health and the leading cause of death worldwide.[1] The incidence of CVD caused 17.6 million deaths in 2016, an increase of 14.5% from 2006 to 2016.[2] Unfortunately, the mortality and morbidity rates of CVD are increasing year by year, especially in developing regions. Studies have shown that approximately 80% of CVD-related deaths occur in low- and middle-income countries. Besides, these deaths occur at a younger age than in high-income countries.[3]?

关键词： Artificial intelligence Cardiovascular diseases Machine learning

Global Well-posedness of the Non-isentropic Full Compressible Magnetohydrodynamic Equations

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Acta Mathematica Sinica,English Series 2016年第2期32卷 227-250页

作者： Fu Yi XU Xin guang ZHANG Yong Hong WU lou CACCETTA State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower Research School of Science Shandong University of Technology School of Mathematical and Informational Sciences Yantai University Department of Mathematics and Statistics Curtin University Department of Mathematics Zhongnan University of Economics and Law

In this paper, we are concerned with Cuuchy problem for the multi-dimensional （N 〉_ 3） non-isentropic full compressible magnetohydrodynamic equations. We prove the existence and unique- ness of a global strong solution to the system for the initial data close to a stable equilibrium state in critical Besov spaces. Our method is mainly based on the uniform estimates in Besov spaces for the proper linearized system with convective terms.

关键词： Global well-posedness full compressible magnetohydrodynamic equations Besov spaces