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Brake Subharmonic Solutions of Subquadratic Hamiltonian Systems

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Chinese Annals of Mathematics,Series B 2016年第3期37卷 405-418页

作者： chong LI Basic Department Beijing Union University

The author mainly uses the Galerkin approximation method and the iteration inequalities of the L-Maslov type index theory to study the properties of brake subharmonic solutions for the Hamiltonian systems z（t） = JVH（t, z（t））, where H（t, z） = 1/2（B（t）z, z）＋ H（t, z）, B（t） is a semipositive symmetric continuous matrix and H is unbounded and not uniformly coercive. It is proved that when the positive integers j and k satisfy the certain conditions, there exists a jT-periodic nonconstant brake solution zj such that zj and zkj are distinct.

关键词： Brake subharmonic solution L-Maslov type index Hamiltonian systems

The Existence of Solutions of Elliptic Equations with Neumann Boundary Condition for Superlinear Problems

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Acta Mathematica Sinica,English Series 2004年第6期20卷 965-976页

作者： chong LI Institute of Mathematics Academy of Mathematics and Systems ScienceChinese Academy of Sciences

In this paper, we study and discuss the existence of multiple solutions of a class of non–linear elliptic equations with Neumann boundary condition, and obtain at least seven non–trivial solutions in which two are positive, two are negative and three are sign–changing. The study of problem (1.1): is based on the variational methods and critical point theory. We form our conclusion by using the sub–sup solution method, Mountain Pass Theorem in order intervals, Leray–Schauder degree theory and the invariance of decreasing flow.

关键词： Critical point theory Order intervals Decreasing flow

Advanced Functional Electromagnetic Shielding Materials:A Review Based on Micro‑Nano Structure Interface Control of Biomass Cell Walls

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Nano-Micro Letters 2025年第1期17卷 98-134页

作者： Yang Shi Mingjun Wu Shengbo Ge Jianzhang Li Anoud Saud Alshammari Jing Luo Mohammed A.Amin Hua Qiu Jinxuan Jiang Yazeed M.Asiri Runzhou Huang Hua Hou Zeinhom M.El‑Bahy Zhanhu Guo chong Jia Kaimeng Xu Xiangmeng Chen Co‑Innovation Center of Efficient Processing and Utilization of Forest Resources College of Materials Science and EngineeringNanjing Forestry UniversityNanjing 210037People’s Republic of China State Key Laboratory of Efficient Production of Forest Resourced Beijing Forestry UniversityQinghua East Road 35Haidian DistrictBeijing 100083People’s Republic of China Department of Physics Faculty of Sciences‑ArarNorthern Border UniversityArar 91431Saudi Arabia Department of Chemistry College of ScienceTaif UniversityP.O.Box 1109921944 TaifSaudi Arabia Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China Integrated Composites Lab Department of Mechanical and Construction EngineeringNorthumbria UniversityNewcastle Upon Tyne NE18STUK College of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024People’s Republic of China Department of Chemistry Faculty of ScienceAl-Azhar UniversityNasr CityCairo 11884Egypt Yunnan Provincial Key Laboratory of Wood Adhesives and Glued Products International Joint Research Center for Biomass MaterialsSouthwest Forestry UniversityKunming 650224People’s Republic of China School of Science Henan Agricultural UniversityZhengzhou 450002People’s Republic of China

Research efforts on electromagnetic interference(EMI)shielding materials have begun to converge on green and sustainable biomass *** materials offer numerous advantages such as being lightweight,porous,and *** to their porous nature,interfacial compatibility,and electrical conductivity,biomass materials hold significant potential as EMI shielding *** concerted efforts on the EMI shielding of biomass materials have been reported,this research area is still relatively new compared to traditional EMI shielding *** particular,a more comprehensive study and summary of the factors influencing biomass EMI shielding materials including the pore structure adjustment,preparation process,and micro-control would be *** preparation methods and characteristics of wood,bamboo,cellulose and lignin in EMI shielding field are critically discussed in this paper,and similar biomass EMI materials are summarized and *** composite methods and fillers of various biomass materials were *** paper also highlights the mechanism of EMI shielding as well as existing prospects and challenges for development trends in this field.

关键词： Biomass materials Electromagnetic interference shielding Micro-nano structure interface control Conductivity

Approximate Representation of Bergman Submodules

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Chinese Annals of Mathematics,Series B 2016年第2期37卷 221-234页

作者： chong ZHAO School of Mathematics Shandong University

In the present paper, the author shows that if a homogeneous submodule M of the Bergman module L_a^2(B_d) satisfies P_M-sum from i to ( M_(zi)P_MM*_(zi))≤c/(N + 1)P_M for some number c > 0, then there is a sequence {f_j } of multipliers and a positive number c such that c'P_M ≤sum from j to ( M_(fj)M*_(fj))≤ P_M, i.e., M is approximately representable. The author also proves that approximately representable homogeneous submodules are p-essentially normal for p > d.

关键词： Approximate representation Essential normality Bergman submodule

Preparation of earthquake-triggered landslide inventory maps using remote sensing and GIS technologies:Principles and case studies

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Geoscience Frontiers 2015年第6期6卷 825-836页

作者： chong Xu Key Laboratory of Active Tectonics and Volcano Institute of GeologyChina Earthquake Administration

Inventory maps of earthquake-triggered landslides can be constructed using several methods,which are often subject to obvious differences due to lack of commonly accepted criteria or principles,To solve this problem,the author describes the principles for preparing inventory maps of earthquake-triggered landslides,focusing on varied methods and their criteria,The principles include the following key points：all landslides should be mapped as long as they can be recognized from images;both the boundary and source area position of landslides should be mapped;spatial distribution pattern of earthquake-triggered landslides should be continuous;complex landslides should be divided into distinct groups;three types of errors such as precision of the location and boundary of landslides,false positive errors,and false negative errors of earthquake-triggered landslide inventories should be controlled and reduced;and inventories of co-seismic landslides should be constructed by the visual interpretation method rather than automatic extraction of satellite images or/and aerial photographs,In addition,selection of remote sensing images and creation of landslides attribute database are also discussed in this paper,Then the author applies these principles to produce inventory maps of four events：the 12 May 2008 Wenchuan,China M_w 7.9,14 April 2010 Yushu,China M_w 6,9,12 January 2010 Haiti M_w7.0,and 2007 Aysen Fjord,Chile M_w 6.2,The results show obvious differences in comparison with previous studies by other researchers,which again attest to the necessity of establishment of unified principles for preparation of inventory maps of earthquake-triggered landslides.

关键词： Earthquake-triggered landslides Inventory Principle GIS Aerial photographs Satellite images

The Study of Minimal Period Estimates for Brake Orbits of Autonomous Subquadratic Hamiltonian Systems

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Acta Mathematica Sinica,English Series 2015年第10期31卷 1645-1658页

作者： chong LI Basic Department Beijing Union University

In this paper, we consider the minimal period estimates for brake orbits of autonomous subquadratic Hamiltonian systems. We prove that if the Hamiltonian function H ∈ C2（R2n,R） is unbounded and not uniformly coercive, there exists at least one nonconstant T-periodic brake orbit （z, T） with minimal period T or T/2 for every number T 〉 0.

关键词： Brake orbits minimal period L-Maslov type index Hamiltonian systems

On Effectiveness of Protocol Creating Maximum Entanglement of Two Charge-Phase Qubits by Cavity Field

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Communications in Theoretical Physics 2007年第5X期48卷 935-942页

作者： LI chong Department of Physics Dalian University of Technology Dalian 116024 China Institute of Theoretical Physics The Chinese Academy of Sciences Beijing 100080 China Applied Physics Department Beijing University of Technology Beijing 100022 China

We revisit the protocols to create maximally entangled states between two Josephson junction （33） charge phase qubits coupled to a microwave field in a cavity as a quantum data bus. We analyze a novel mechanism of quantum decoherence due to the adiabatic entanglement between qubits and the data bus, the off-resonance microwave field. We show that even if the variable of the data bus can be adiabatically eliminated, the entanglement between the qubits and data bus remains and can decohere the superposition of two-particle state. Fortunately we can construct a decoherencefree subspace of two-dimension to against this adiabatic decoherence. To carry out the analytic study for this decoherence problem, we develop Frohlich transformation to re-derive the effective Hamiltonian of these systems, which is equivalent to that obtained from the adiabatic elimination approach.

关键词： SQUID quantum entanglement conccurrence decoherence free sub-space

Facile One-Pot Green Synthesis and Antibacterial Activities of GO/Ag Nanocomposites

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Acta Metallurgica Sinica(English Letters) 2017年第1期30卷 36-44页

作者： chong-chong Liu Hui Xu Lei Wang Xuan Qin College of Chemistry and Materials Science Ludong UniversityYantai 264025China College of Life Sciences Ludong UniversityYantai 264025China School of Materials Science and Engineering Lanzhou University of TechnologyLanzhou 730050China

New materials with good antibacterial activity synthesized by simple, environmentally friendly method have attracted numerous research interests. Taking advantage of Ag and graphene oxide （GO）, the GO/Ag nanocomposites were prepared by a facile, green ＂one-pot＂ reaction to achieve superior antibacterial properties. AgNO3 is as a precursor of Ag nanoparticles （Ag NPs）, and the grape seeds extract as an environmentally friendly reducing and stabilizing agent. The asprepared GO/Ag nanocomposites were characterized by various technologies. The results indicated that the silver ion was reduced by the grade seeds extract and Ag NPs were decorated on the surface of GO nanosheets successfully. The average size of the Ag NPs anchored on the GO surface was 40-50 nm. In this study, we prepared GO/Ag nanocomposites with different Ag NPs to GO ratios and carefully investigated their antibacterial activities. We found that the GO/Ag nanocomposites show better antibacterial activity when the concentration of AgNO3 is 2 mM. GO/Ag nanocomposites have a minimum inhibitory concentration 23.8 μg/mL, lower than bare Ag NPs 25.5 μg/mL. We try to explain the antibacterial mechanism based on optical microscopy observation.

关键词： GO/Ag nanocomposites Green "one-pot" reaction Superior antibacterial properties

Numerical interpretation of transient permeability test in tight rock

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第1期10卷 32-41页

作者： chong Cao Department of Civil Engineering and Applied Mechanics McGill University

Pulse-decay method has been widely used to estimate the fluid transport properties of low-permeability geomaterials. In this context, radial flow transient pulse test is conducted to measure the water permeability of Cobourg limestone hollow cylinder. The proposed method applies hydraulic pulses to the sealed central cavity and then the cavity pressure dissipates as the fluid migrates into the saturated rock matrix. The influence of entrapped air bubbles within the pressurized cavity is crucial to interpreting permeability from transient pulse test. The modeling results indicate that the air inclusions can significantly increase the fluid compressibility and thus delay the hydraulic pulse decay process, which may lead to the underestimation of the rock permeability.

关键词： Pulse-decay method Low-permeability Air-water mixture Compressibility