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Global Exact Boundary Controllability for Cubic Semi-linear Wave Equations and Klein-Gordon Equations

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Chinese Annals of Mathematics,Series B 2010年第1期31卷 35-58页

作者： Yi ZHOU Wei XU zhen lei Key Laboratory of Mathematics for Nonlinear sciences School of Mathematical Sciences Fudan University Shanghai 200433 China school of mathematical sciences Fudan University Shanghai 200433 China

The authors prove the global exact boundary controllability for the cubic semilinear wave equation in three space dimensions,subject to Dirichlet,Neumann,or any other kind of boundary controls which result in the well-posedness of the corresponding initial-boundary value *** exponential decay of energy is first established for the cubic semi-linear wave equation with some boundary condition by the multiplier method,which reduces the global exact boundary controllability problem to a local *** proof is carried out in line with [2,15].Then a constructive method that has been developed in [13] is used to study the local *** when the region is star-complemented,it is obtained that the control function only need to be applied on a relatively open subset of the *** the cubic Klein-Gordon equation,similar results of the global exact boundary controllability are proved by such an idea.

关键词： Global exact boundary controllability Cubic semi-linear wave equations The exponential decay Star-shaped Star-complemented Cubic Klein- Gordon equations

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Accurate atomic scanning transmission electron microscopy analysis enabled by deep learning

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Nano Research 2024年第4期17卷 2971-2980页

作者： Tianshu Chu lei Zhou Bowei Zhang Fu-zhen Xuan shanghai Key Laboratory of Intelligent Sensing and Detection Technology East China University of Science and TechnologyShanghai 200237China school of Mechanical and Power Engineering East China University of Science and TechnologyShanghai 200237China Key Laboratory of Pressure Systems and Safety of Ministry of Education East China University of Science and TechnologyShanghai 200237China

Currently,the machine learning(ML)-based scanning transmission electron microscopy(STEM)analysis is limited in the simulative stage,its application in experimental STEM is needed but ***,we built up a universal model to analyze the vacancy defects and single atoms accurately and rapidly in experimental STEM images using a full convolution *** our model,the unavoidable interference factors of noise,aberration,and carbon contamination were fully considered during the training,which were difficult to be considered in the *** toward the simultaneous identification of various vacancy types and low-contrast single atoms in the low-quality STEM images,our model showed rapid process speed(45 images per second)and high accuracy(>95%).This work represents an improvement in experimental STEM image analysis by ML.

关键词： deep learning low-dimensional materials atomic defects single atoms

Data-driven rational design of single-atom materials for hydrogen evolution and sensing

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Nano Research 2024年第4期17卷 3352-3358页

作者： lei Zhou Pengfei Tian Bowei Zhang Fu-zhen Xuan shanghai Key Laboratory of Intelligent Sensing and Detection Technology East China University of Science and TechnologyShanghai 200237China school of Mechanical and Power Engineering East China University of Science and TechnologyShanghai 200237China Key Laboratory of Pressure Systems and Safety of Ministry of Education East China University of Science and TechnologyShanghai 200237China

Herein we proposed a data-driven high-throughput principle to screen high-performance single-atom materials for hydrogen evolution reaction(HER)and hydrogen sensing by combing the theoretical computations and a topology-based multi-scale convolution kernel machine learning *** the rational training by 25 groups of data and prediction of all 168 groups of single-atom materials for HER and sensing,respectively,a high prediction accuracy(>0.931 R^(2) score)was achieved by our *** show that the promising HER catalysts include Pt atoms in C_(4) and Sc atoms in C_(1)N_(3) coordination ***,Y atoms in C_(4) coordination environment and Cd atoms in C_(2)N_(2)-ortho coordination environment were predicted with great potential as hydrogen sensing *** method provides a way to accelerate the discovery of innovative materials by avoiding the time-consuming empirical principles in experiments.

关键词： machine learning single-atom materials sensing hydrogen evolution

Advancements and challenges in bionic joint lubrication biomaterials for sports medicine

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Biosurface and Biotribology 2024年第3期10卷 89-105页

作者： lei Xiang zhen Wang Wenguo Cui Department of Orthopaedics Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint DiseasesShanghai Institute of Traumatology and OrthopaedicsRuijin HospitalShanghai Jiao Tong University School of MedicineShanghaiChina

Bionic lubricant materials are a class of materials inspired by natural organisms and offer excellent lubrication properties and *** the field of sports medicine,their application opens up new possibilities for the prevention and treatment of sports-related *** authors will introduce the existing theoretical models of friction in the locomotor system,the characteristics and advantages of biomimetic lubrication materials and discuss in depth their applications in the field of sports *** development of bionic lubrication materials opens up unprecedented opportunities for sports medicine to provide more effective and long-lasting treatment options for patients.

关键词： biointerface bio-lubricant biomaterials biomedical application medicine

Stress relaxation properties of calcium silicate hydrate:a molecular dynamics study

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Journal of Zhejiang university-Science A(Applied Physics & Engineering) 2024年第2期25卷 97-115页

作者： Zhicheng GENG Shengwen TANG Yang WANG Hubao A zhen HE Kai WU lei WANG State Key Laboratory of Water Resources Engineering and Management Wuhan UniversityWuhan430072China Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education School of Materials Science and EngineeringTongji UniversityShanghai200092China College of Materials Science and Engineering Xi’an University of Architecture and TechnologyXi’an710055China

The time-dependent viscoelastic response of cement-based materials to applied deformation is far from fully understood at the atomic *** silicate hydrate(C-S-H),the main hydration product of Portland cement,is responsible for the viscoelastic mechanism of cement-based *** this study,a molecular model of C-S-H was developed to explain the stress relaxation characteristics of C-S-H at different initial deformation states,Ca/Si ratios,temperatures,and water contents,which cannot be accessed *** stress relaxation of C-S-H occurs regardless of whether it is subjected to initial shear,tensile,or compressive deformation,and shows a heterogeneous *** plays a crucial role in the stress relaxation process.A large Ca/Si ratio and high temperature reduce the cohesion between the calcium-silicate layer and the interlayer region,and the viscosity of the interlayer region,thereby accelerating the stress relaxation of *** effect of the hydrogen bond network and the morphology of C-S-H on the evolution of the stress relaxation characteristics of C-S-H at different water contents was elucidated by nonaffine mean squared *** results shed light on the stress relaxation characteristics of C-S-H from a microscopic perspective,bridging the gap between the microscopic phenomena and the underlying atomic-level mechanisms.

关键词： Calcium silicate hydrate(C-S-H) Stress relaxation Ca/Si ratio Temperature Water content Atomic simulation

The top-order energy of quasilinear wave equations in two space dimensions is uniformly bounded

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Fundamental Research 2024年第2期4卷 270-283页

作者： Shijie Dong Philippe G.LeFloch zhen lei Southern university of Science and Technology SUSTech International Center for Mathematicsand Department of MathematicsShenzhen 518055China fudan university School of Mathematical Sciences220 Handan RoadShanghai 200433China Laboratoire Jacques-Louis Lions and Centre National de la Recherche Scientifique Sorbonne Université4 Place JussieuParis 75252France shanghai Center for mathematical sciences Shanghai 200433China

Alinhac solved a long-standing open problem in 2001 and established that quasilinear wave equations in two space dimensions with quadratic null nonlinearities admit global-in-time solutions,provided that the initial data are compactly supported and sufficiently small in Sobolev *** this work,Alinhac obtained an upper bound with polynomial growth in time for the top-order energy of the solutions.A natural question then arises whether the time-growth is a true phenomenon,despite the possible conservation of basic *** the present paper,we establish that the top-order energy of the solutions in Alinhac theorem remains globally bounded in time.

关键词： Quasilinear wave equation Global-in-time solution Uniform energy bounds Quadratic null nonlinearity Hyperboloidal foliation method Vector field method

Semantic Search among Heterogeneous Biological Databases Based on Gene Ontology

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Acta Biochimica et Biophysica Sinica 2004年第5期36卷 365-370页

作者： Shun-Liang CAO, lei QIN1, Wei-Zhong HE1, Yang ZHONG2, Yang-Yong ZHU, and Yi-Xue LI1,3* Department of Computing and Information Technology, fudan university, shanghai 200433, china shanghai Center for Bioinformation 1 Technology, shanghai 200235, china school of Life sciences, fudan university, shanghai 200433, china Bioinformation Center of shanghai Institutes for Biological sciences, the Chinese Academy of sciences, shanghai 200031, china Department of Computing and Information Technology Fudan University Shanghai 200433 China shanghai Center for Bioinformation Technology shanghai 200235 China school of Life sciences Fudan University Shanghai 200433 China Bioinformation Center of shanghai Institutes for Biological sciences the Chinese Academy of Sciences Shanghai 200031 China

Semantic search is a key issue in integration of heterogeneous biological databases. In this paper, we present a methodology for implementing semantic search in BioDW, an integrated biological data warehouse. Two tables are presented: the DB2GO table to correlate Gene Ontology (GO) annotated entries from BioDW data sources with GO, and the semantic similarity table to record similarity scores derived from any pair of GO terms. Based on the two tables, multifarious ways for semantic search are provided and the corresponding entries in heterogeneous biological databases in semantic terms can be expediently searched.

关键词： Gene Ontology semantic search BioDW

Simultaneous Degradation, Dehalogenation, and Detoxification of Halogenated Antibiotics by Carbon Dioxide Radical Anions

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Engineering 2024年第6期37卷 78-86页

作者： Yanzhou Ding Xia Yu Shuguang Lyu Huajun zhen Wentao Zhao Cheng Peng Jiaxi Wang Yiwen Zhu Chengfei Zhu lei Zhou Qian Sui State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process School of Resources and Environmental EngineeringEast China University of Science and TechnologyShanghai 200237China shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China shanghai Academy of Environmental sciences Shanghai 200233China

Despite the extensive application of advanced oxidation processes(AOPs)in water treatment,the efficiency of AOPs in eliminating various emerging contaminants such as halogenated antibiotics is constrained by a number of *** moieties exhibit strong resistance to oxidative radicals,affecting the dehalogenation and detoxification *** address these limitations of AOPs,advanced reduction processes(ARPs)have been ***,a novel nucleophilic reductant—namely,the carbon dioxide radical anion(CO_(2)^(·-))—is introduced for the simultaneous degradation,dehalogenation,and detoxification of florfenicol(FF),a typical halogenated *** results demonstrate that FF is completely eliminated by CO_(2)^(·-),with approximately 100%of Cland 46%of Freleased after 120 min of *** detoxification is observed,which exhibits a linear response to the release of free inorganic halogen ions(R^(2)=0.97,p75%)in degrading a series of halogenated antibiotics,including chloramphenicol(CAP),thiamphenicol(THA),diclofenac(DLF),triclosan(TCS),and ciprofloxacin(CIP).The system shows high tolerance to the pH of the solution and the presence of natural water constituents,and demonstrates an excellent degradation performance in actual groundwater,indicating the strong application potential of CO_(2)^(·-)-based ARPs in real ***,this study elucidates the feasibility of CO_(2)^(·-)for the simultaneous degradation,dehalogenation,and detoxification of halog

关键词： Carbon dioxide radical anions Advanced reduction processes Halogenated antibiotics Dehalogenation Detoxification

Preparation and Structure-Property Regulation Mechanism of Reversible Thermochromic Polydiacetylene

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Chinese Journal of Polymer Science 2024年第8期42卷 1111-1121页

作者： Zhi-Qing Ge Shuo Yan Zu-Xiong Pan Shan lei Xuan-Zhi Mao Chu Zhao Mo-zhen Wang Xue-Wu Ge Key Laboratory of Precision and Intelligent Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China Marshall Laboratory of Biomedical Engineering International Cancer CenterLaboratory of Evolutionary Theranostics(LET)School of Biomedical EngineeringShenzhen University Medical SchoolShenzhen UniversityShenzhen 518055China shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China university of Chinese Academy of sciences Beijing 100049China

The thermochromic mechanism and the structure-property regulation principle of reversible thermochromic polydiacetylene(PDA)materials have always been a challenging *** this work,a series of diacetylene monomers(m-PCDA)containing phenyl and amide or carboxyl groups were synthesized from 10,12-pentacosadiynoic acid(PCDA)through the esterification or amidation *** effects of the number and the distribution of the functional groups in m-PCDA molecules on their solid-state polymerization capability,and the thermochromic mechanism of their corresponding polymers(m-PDA)were investigated and discussed in *** results show that the m-PCDA monomers containing both benzene ring and groups that can form hydrogen bonding interactions have strong intermolecular interaction,and are easy to carry out the solid phase polymerization under 254-nm UV irradiation to obtain the corresponding new thermochromic m-PDA *** thermochromic behavior of m-PDA depends on its melting *** initial color-change temperature(blue to red)is determined by the onset melting tem perature,and the temperature range in which reversible color recovery can be achieved by repeat heating-cooling treatment is determined by its melting *** to the proposed thermochromic mechanism of PDA,various new PDA materials with precise thermochromic temperatu res and reversible thermochromic temperature ra nges can be designed and synthesized through the appropriate introduction of benzene ring and groups that can form hydrogen bonding interactions into the molecular structure of linear diacetylene *** work provides a perspective to the precise molecular structure design and the property regulation of the reversible thermochromic PDA materials.

关键词： Polydiacetylene Thermochromism Hydrogen bonding Chemical modification

维普期刊数据库