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Chinese Medical Journal 2016年第23期129卷 2898-2898页

作者： chen-lu Yang Kai Shen Qi-Bing Xie Geng Yin Department of Hematology West China Hospital Sichuan University Chengdu Sichuan 610041 China Department Of Rheumatology and I-mmunology West China Hospital Sichuan University Chengdu Sichuan 610041 China

We are pleased to receive the letter from the reader about our article Herein, we are willing to respond to some of their comments. In our case, we reported a senile Chinese man with a 2-month history of fever accompa...

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Chemical Empiricism 2.0 at Age of Big Data: Large-scale Prediction of Reaction Pathways Based on Bond Dissociation Energies

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Chinese Journal of Chemical Physics 2015年第6期28卷 -页

作者： Shi-lu chen Key Laboratory of Cluster Science of Ministry of Education School of Chemistry Beijing Institute of Technology Beijing 100081 China

A programmable algorithm using bond dissociation energies has been proposed for the prediction of reaction pathways. It has been successfully applied to a gas-phase reaction of F2+CH3Cl, with the accurate revelation of the most favorable product CF4 and its corresponding reaction pathway. This acts as an inspiring example of chemical empiricism 2.0, and may open the door for the large-scale prediction of reaction pathways at the age of big data.

关键词： Big data Bond dissociation energy Reaction pathway Prediction

Interactive multiobjective evolutionary algorithm based on decomposition and compression

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Science China(Information Sciences) 2021年第10期64卷 166-181页

作者： lu chen Bin XIN Jie chen School of Automation Beijing Institute of Technology State Key Laboratory of Intelligent Control and Decision of Complex Systems

Many real-world optimization problems involve multiple conflicting objectives. Such problems are called multiobjective optimization problems(MOPs). Typically, MOPs have a set of so-called Pareto optimal solutions rather than one unique optimal solution. To assist the decision maker(DM) in finding his/her most preferred solution, we propose an interactive multiobjective evolutionary algorithm(MOEA)called iDMOEA-εC, which utilizes the DM’s preferences to compress the objective space directly and progressively for identifying the DM’s preferred region. The proposed algorithm employs a state-of-the-art decomposition-based MOEA called DMOEA-εC as the search engine to search for solutions. DMOEA-εC decomposes an MOP into a series of scalar constrained subproblems using a set of evenly distributed upper bound vectors to approximate the entire Pareto front. To guide the population toward only the DM’s preferred part on the Pareto front, an adaptive adjustment mechanism of the upper bound vectors and two-level feasibility rules are proposed and integrated into DMOEA-εC to control the spread of the population. To ease the DM’s burden, only a small set of representative solutions is presented in each interaction to the DM,who is expected to specify a preferred one from the set. Furthermore, the proposed algorithm includes a two-stage selection procedure, allowing to elicit the DM’s preferences as accurately as possible. To evaluate the performance of the proposed algorithm, it was compared with other interactive MOEAs in a series of experiments. The experimental results demonstrated the superiority of iDMOEA-εC over its competitors.

关键词： multiobjective optimization interactive decision making preference incorporation decomposition compression

A critical Trudinger-Moser inequality involving a degenerate potential and nonlinear Schrodinger equations

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Science China Mathematics 2021年第7期64卷 1391-1410页

作者： lu chen Guozhen lu Maochun Zhu School of Mathematics and Statistics Beijing Institute of TechnologyBeijing 100081China Department of Mathematics University of ConnecticutStorrsCT 06269USA School of Mathematical Sciences Institute of Applied System AnalysisJiangsu UniversityZhenjiang 212013China

The classical critical Trudinger-Moser inequality in R^(2)under the constraint∫_(R_(2))(|▽u|^(2)+|u|^(2))dx≤1 was established through the technique of blow-up analysis or the rearrangement-free argument:for anyτ>0,it holds that sup u∈H^(1)(r^(2)fR^(2)(τ|U|^(2)+|▽u|^(2)dx≤1∫_(R^(2)(E^4π|u|^(2)-1)dx≤C(τ)lutions to the following Sciridinger equations with critical exponeitial growth:-Δu+V(x)u=f u)in R^(2),(0.1)where V(x)≥0 and vanishes on an open set of R^(2)and f has critical exponential *** a positive constant lower bound for the potential V(x)(e.g.,the Rabinowitz type potential)has been the standard assumption when one deals with the existence of solutions to the above Schrodinger equations when the nonlinear term has the exponential *** existence result seems to be the first one without this standard assumption.

关键词： Trudinger-Moser inequalities degenerate potential ground state solutions Schrodinger equations Nehari manifold

Bimetallic metal-organic framework derived doped carbon nanostructures as high-performance electrocatalyst towards oxygen reactions

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Nano Research 2021年第5期14卷 1533-1540页

作者： lu chen Zhi chen Xudong Liu Xiaolei Wang Department of Chemical and Materials Engineering Concordia UniversityMontrealQuebecH3G 1M8Canada Department of Building Civil and Environmental EngineeringConcordia UniversityMontrealQuebecH3G 1M8Canada Department of Chemical and Materials Engineering University of AlbertaEdmontonAlbertaT6G 1H9Canada

Rational design and development of cost-effective, highly active and durable bifunctional electrocatalysts towards oxygen redox reactions is of critical importance but great challenge for the broad implementation of next-generation metal-air batteries for electric transportation. Herein, a high-performance electrocatalyst of cobalt and zinc sulfides nanocrystals embedded within nitrogen and sulfur co-doped porous carbon is successfully designed and derived from bimetallic metal-organic frameworks of cobalt and zinc containing zeolitic imidazolate frameworks. The unique nanostructure contains abundant electrocatalytic active sites of sulfides nanocrystals and nitrogen and sulfur dopants which can be fast accessed through highly porous structure originate from both zinc vaporization and sulfurization processes. Such bifunctional electrocatalyst delivers a superior half-wave potential of 0.86 V towards oxygen reduction reaction and overpotential of 350 mV towards oxygen evolution reaction, as well as excellent durability owing to the highly stable carbon framework with a great graphitized portion. The performance boosting is mainly attributed to the unique nanostructure where bimetallic cobalt and zinc provide synergistic effect during both synthesis and catalysis processes. The design and realization pave a new way of development and understanding of bifunctional electrocatalyst towards clean electrochemical energy technologies.

关键词： bimetallic metal-organic frameworks carbon nanostructures electrocatalysts oxygen redox reactions nitrogen and sulfur doping

Hardy–Littlewood–Sobolev Inequalities with the Fractional Poisson Kernel and Their Applications in PDEs

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Acta Mathematica Sinica,English Series 2019年第6期35卷 853-875页

作者： lu chen Guozhen lu Chunxia TAO School of Mathematics and Statistics Beijing Institute of Technology Department of Mathematics University of Connecticut School of Mathematical Sciences Beijing Normal University

The purpose of this paper is five-fold. First, we employ the harmonic analysis techniques to establish the following Hardy–Littlewood–Sobolev inequality with the fractional Poisson kernel on the upper half space ■ where f ∈ L^p(?R_+~n), g ∈ Lq(R_+~n) and p, q'∈(1, +∞), 2 ≤α lutions to the integral system of the Euler–Lagrange equations associated with the extremals of the fractional Poisson kernel. Finally, by using the method of moving plane in integral forms, we prove that extremals of the Hardy–Littlewood–Sobolev inequality with the fractional Poisson kernel must be radially symmetric and decreasing about some point ξ_0 ∈ ?R_+~n. Our results proved in this paper play a crucial role in establishing the Stein–Weiss inequalities with the Poisson kernel in our subsequent paper.

关键词： Existence of extremal functions Hardy–Littlewood–Sobolev inequality Moving plane method Poisson kernel

A comparative DFT+U study of CO oxidation on Pd-and Zr-doped ceria

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Journal of Rare Earths 2023年第7期41卷 1042-1048,I0003页

作者： lu chen Xinping Wu Xueqing Gong Key Laboratory for Advanced Materials and Joint International Research Laboratory for Precision Chemistry and Molecular Engineering Feringa Nobel Prize Scientist Joint Research CenterFrontiers Science Center for Materiobiology and Dynamic ChemistryCentre for Computational Chemistry and Research Institute of Industrial CatalysisSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

Metal-doped ceria catalysts have been applied in many important catalytic *** this work,we performed density functional theory calculations corrected by on-site Coulomb interactions to study the Pd-and Zr-doped CeO_(2)(111) surfaces with the dopant at different *** formation of oxygen vacancies and CO oxidation were systematically calculated on the various doped *** find that both Pd and Zr doping can activate the surface lattice O and reduce the energy barriers of CO ***,the promotion effect of the Zr dopant is limited to its existence in the first surface layer,while for the Pd dopant,the surface activity can be greatly enhanced even it occurs far below the ***,CO_(2) can be generated directly on the Pd-doped surfaces through reaction between CO and surface O,while the surface intermediate CO_(2)^(δ-) may readily form and restrict the releasing of CO_(2) by further oxidation to carbonates on the Zr-doped *** analyses show that the doped Pd exists as Pd^(4+) and it has stronger electron affinity than other surface species during CO oxidation,contributing to the easy Pd^(4+) to Pd^(2+) transformation accompanied by direct CO_(2) formation at Pd-doped ceria.

关键词： CeO_(2) Metal doping CO oxidation Carbonate DFT+U Rare earths

Coupling and coordinated evolution characteristics of regional economy-energy-carbon emission multiple systems:A case study of main China's Basin

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Journal of Environmental Sciences 2024年第6期140卷 204-218页

作者： lu chen Xin Li Jingyi Zhao Xinyu Kang lu Liu Minxi Wang Wu chen College of Management Science Chengdu University of TechnologyChengdu 610051China SDU Life Cycle Engineering Department of Green TechnologyUniversity of Southern Denmark5230 OdenseDenmark

Comprehensive analysis of the Economy-Energy-Carbon Emission(EECE)system is beneficial for promoting sustainable social *** study analyzes the system development of major watersheds in China from 2010 to *** research fully considers the system’s internal and external inputs and outputs and proposes an evaluation index system for regional EECE coupling and coordinated ***,using the difference in system weight allocation to improve the coupling and coordination model,the study explores the dynamic system’s coupling and *** results show that(1)The development of the system structure is relatively stable,but the overall development status is not ideal;(2)The downstream of China’s main river basins has obvious economic advantages,while the energy system fluctuates *** efficiency of the carbon emission system will decrease in areas with rapid economic *** coupling and coordination level of the EECE system is better in the Yangtze River Basin than in the Yellow River Basin;(3)From the perspective of dynamic coordinated development,the main river basins have been divided into two states since 2012,but it is relatively stable *** dynamic coordination is often at a disadvantage in regions with rapid economic and energy development;(4)The coupling coordination degree of the two river basins has significant positive spatial *** provinces’significant spatial clustering characteristics of the coupling coordination degree are High-High ***-Low type provinces are mainly concentrated *** research process has certain reference significance for the collaborative governance of complex regional systems.

关键词： System structure Efficiency measure Coupling mechanism Dynamic coordination

An Improved Model of the Jovian Magnetosphere

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Chinese Physics Letters 2014年第3期31卷 184-186页

作者： lu Bin chen Chu-Xin Key Laboratory of Geospace Environment Department of Geophysics and Planetary Sciences School of Earth and Space Sciences University of Science and Technology of China Hefei 230026

The Jovian magnetosphere is modulated by the solar wind and centrifugal force. The configuration of the magnetic field in the previous model of the magnetosphere including the centrifugal force is consistent with the observations at low magnetic latitude （Λ〈50°）, while there is a substantial difference between the results of the model and the observations at high magnetic latitude （Λ≥50°）, especially in the distant magnetotail. Based on the previous model, a new configuration of the Jovian magnetosphere in the night side is suggested by a three-step transformation in this study. The new magnetosphere obtained by the transformation method is flattened in the z-direction and stretched in the x-direction in distant magnetotail, which agree with general knowledge.

关键词： Magnetosphere

Flocking and clustering in mixtures of self-propelled particles with or without active reorientation

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Communications in Theoretical Physics 2023年第11期75卷 135-141页

作者： lu chen Z C Tu Department of Physics Beijing Normal UniversityBeijing 100875China Complex Systems Division Beijing Computational Science Research CenterBeijing 100193China

We study phase behaviors of mixtures comprising active particles with and without active reorientation by varying mixing *** observe that the order parameter characterizing flocking in the steady state exhibits a linear decrease with an increase in mixing *** the order parameter characterizing clustering in the steady state presents a sharp leap as the mixing ratio ***,we obtain phase diagrams of flocking under different mixing ratios and observe that the domain corresponding to flocking experiences a contraction with the increase of mixing ***,the coordinates of the critical point on the phase boundary between the flocking and the disordered phase decay exponentially with the mixing ratio.

关键词： active matter flocking clustering binary system