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Friction 2024年第4期12卷 745-779页

作者： Haoyuan LUO Siyu CHEN Leyi ZHU xiyin LIU Yangzezhi zheng Runming ZHAO Xiaoming HUANG School of Transportation Southeast UniversityNanjing 211189China National Demonstration Center for Experimental Education of Road and Traffic Engineering Southeast UniversityNanjing 211189China

Many rubber friction theories or some method combined theories and field-experiments are employed to evaluate the pavement skid-resistance deterioration due to the evolution of surface ***,these methods are difficult to be implemented in the analysis of situations with multi-factor coupling and some extreme *** study developed a framework to evaluate the skid-resistance deterioration of asphalt *** this framework,the portable laser scanning was used to create the digital worn pavement model,and a hydroplaning finite element(FE)model for these digital worn pavements was constructed to evaluate coupling effects of the texture evolution and factors of slip ratio,slip angle,velocity and water film on braking-cornering characteristics of *** this study,the deterioration of skid-resistance of five typical asphalt pavements due the surface texture wear was systematically investigated by this *** with previous works,this study established the rubber friction models for each digital worn pavement considering the energy hysteresis of rubber and the power spectrum density of surface *** the rubber friction model was used to define the interaction behaviors between the tire and corresponding wore pavements in the FE hydroplaning model,rather than using an empirical friction model or a fixed friction coefficient.

关键词： worn pavement skid-resistance friction coefficient textures evolution water film computer numerical simulation

A Series of Convex Functions on a Banach Space

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Acta Mathematica Sinica,English Series 1998年第1期14卷 77-84页

作者： zheng xiyin department of mathematics, yunnan university, kunming 650091. china

A series of convex functions on a Banach space is studied. The generalizations of the Moreau-Rockafellar theorem are given. As its application, the partial generalization of the Kuhn- Tucker theorem is obtained.

关键词： Pointwise convergence Locally uniform convergence Subdifferential Moreau-Rockafellar theorem Kuhn-Tucker theorem

Regularity of the Attractor for the Dissipative Hamiltonian Amplitude Equation Governing Modulated Wave Instabilities

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Acta Mathematicae Applicatae Sinica 2002年第2期18卷 263-272页

作者： zheng-de Daidepartment of mathematics, yunnan university, kunming 650091. china department of mathematics Yunnan Normal University Kunming China

In the present paper, the existence of global attractor for dissipative Hamiltonian amplitude equation governing the modulated wave instabilities in E0 is considered. By a decomposition of solution operator, it is sho... 详细信息

关键词： Regularity of Global attractor Hamiltonian amplitude equation

Design Principles and Mechanistic Understandings of Non-Noble-Metal Bifunctional Electrocatalysts for Zinc-Air Batteries

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Nano-Micro Letters 2024年第9期16卷 13-48页

作者： yunnan Gao Ling Liu Yi Jiang Dexin Yu Xiaomei zheng Jiayi Wang Jingwei Liu Dan Luo Yongguang Zhang Zhenjia Shi Xin Wang Ya‑Ping Deng Zhongwei Chen Power Battery and Systems Research Center State Key Laboratory of CatalysisDalian Institute of Chemical PhysicsDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023People’s Republic of China department of Chemical Engineering University of WaterlooWaterlooON N2L 3G1Canada Institute of Carbon Neutrality Zhejiang Wanli UniversityNingbo 315100People’s Republic of China College of Materials and Chemistry China Jiliang UniversityHangzhou 310018People’s Republic of China

Zinc-air batteries(ZABs)are promising energy storage systems because of high theoretical energy density,safety,low cost,and abundance of ***,the slow multi-step reaction of oxygen and heavy reliance on noble-metal catalysts hinder the practical applications of ***,feasible and advanced non-noble-metal elec-trocatalysts for air cathodes need to be identified to promote the oxygen catalytic *** this review,we initially introduced the advancement of ZABs in the past two decades and provided an overview of key developments in this ***,we discussed the work-ing mechanism and the design of bifunctional electrocatalysts from the perspective of morphology design,crystal structure tuning,interface strategy,and atomic *** also included theoretical studies,machine learning,and advanced characterization technologies to provide a comprehensive understanding of the structure-performance relationship of electrocatalysts and the reaction pathways of the oxygen redox ***,we discussed the challenges and prospects related to designing advanced non-noble-metal bifunctional electrocatalysts for ZABs.

关键词： Zinc-air batteries Bifunctional electrocatalysts Design principles Mechanistic understandings

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次可分与拟可分的Banach空间

数学学报（中文版） 1994年第1期37卷 43-49页

作者：郑喜印云南大学数学系

Ｘ是Ｂａｎａｃｈ空间，对Ｘ的每一弱可分且弱紧的子集Ｋ，若（ｋ，ω）可度量，则称Ｘ是次可分的。如果对任意的可分，则称Ｘ是拟可分的。本文证明了这两类新引入的空间比可分空间与弱紧生成的Ｂａｎａｃｈ空间都要广泛并且保留了可分... 详细信息

Ｘ是Ｂａｎａｃｈ空间，对Ｘ的每一弱可分且弱紧的子集Ｋ，若（ｋ，ω）可度量，则称Ｘ是次可分的。如果对任意的可分，则称Ｘ是拟可分的。本文证明了这两类新引入的空间比可分空间与弱紧生成的Ｂａｎａｃｈ空间都要广泛并且保留了可分空间的许多重要性质。

关键词：次可分拟可分可分巴拿赫空间

ON MATRIX UNITARILY INVARIANT NORM CONDITION NUMBER

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Journal of Computational mathematics 1998年第2期16卷 121-128页

作者： Dao-sheng zheng (department of mathematics, East china Normal university, Shanghai 200062, china) E china Normal Univ Dept Math Shanghai 200062 Peoples R China

In this paper, the unitarily invariant norm \\.\\ on C-mxn is used. We first discuss the problem under what case, a rectangular matrix A has minimum condition number K(A) = \\A\\ \\A(+)\\, where A(+) designates the Moore-Penrose inverse of A; and under what condition, a square matrix A has minimum condition number for its eigenproblem? Then we consider the second problem, i.e., optimum of K(A) = \\A\\ \\A(-1)\\(2) in error estimation.

关键词： matrix unitarily invariant norm condition number

A FAMILY OF HIGH-ODER PARALLEL ROOTFINDERS FOR POLYNOMIALS

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Journal of Computational mathematics 2000年第3期18卷 283-288页

作者： Shi-ming zheng (department of mathematics, Xixi Campus,Zhejiang university, Hangzhou, 310028, china) 浙江大学浙江杭州 310028

Presents a family of parallel iterations for finding all zeros of a polynomial without evaluation of derivatives. Construction of iterations; Convergence of the iterations; Details on the numerical examples.

关键词： parallel iteration zeros of polynomial order of convergence

APPLICATION OF NEWTON'S AND CHEBYSHEV'S METHODS TO PARALLEL FACTORJZATION OF POLYNOMIALS

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Journal of Computational mathematics 2001年第4期19卷 347-356页

作者： Shi-ming zheng (department of mathematics, Xixi Campus, Zhejiang university, Hangzhou 310028, china) 浙江大学浙江杭州 310028

In this paper it is shown m two different ways that one of the family of parallel iterations to determine all real quadratic factors of polynomials presented in [12] is Newton's method applied to the special equation (1.7) below. Furthermore, we apply Chebyshev's method to (1.7) and obtain a new parallel iteration for factorization of polynomials. Finally, some properties of the parallel iterations are discussed.

关键词： Newton's method Chebyshev's method Parallel iteration Factorization of polynomial.

Theoretical Study on the Dehydrogenation Reaction of H2S by VS+ （3Σ-）

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Chinese Journal of Structural Chemistry 2005年第10期 1111-1116+1101页

作者： GAO Shu-Lina LIU zheng-Meib XIE Xiao-Guanga a(department of Chemistry, yunnan university, kunming 650091. china) b(School of Physics and Chemistry, Guizhou Normal university, Guiyang 550001, china)

The dehydrogenation reaction of H2S by the 3∑- ground state of VS+: VS+ + H2S → VS2+ + H2 has been studied by using Density Functional Theory (DFT) at the B3LYP/DZVP level. It is found that the reaction proceeds along two possible pathways (A and B) yielding two isomer dehydrogenation products VS2+-1 (3B2) and VS2+-2 (3A1), respectively. For both pathways, the reaction has a two-step-reaction mechanism that involves the migration of two hydrogen atoms from S2 to V+, respectively. The migration of the second hydrogen via TS3 and that of the first via TS4 are the rate-determining steps for pathways A and B, respectively. The activation energy is 17.4 kcal/mol for pathway A and 22.8 kcal/mol for pathway B relative to the reactants. The calculated reaction heat of 9.9 kcal/mol indicates the endothermicity of pathway A and that of –11.9 kcal/mol suggests the exothermicity of pathway B.

关键词： density functional theory cationic transition metal sulfide dehydrogenation reaction reaction mechanism

THE BLOWUP OF RADIALLY SYMMETRIC SOLUTIONS FOR 2-D QUASILINEAR WAVEEQUATIONS WITH CUBIC NONLINEARITY

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Chinese Annals of mathematics,Series B 1999年第4期20卷 455-472页

作者： YIN HUICHENG zheng QIN(department of mathematics, Nanjing university Nanjing 210093, china) Nanjing Univ Dept Math Nanjing 210093 Peoples R China

For a special class of quasilinear wave equations with small initial data which satisfy the nondegenerate assumption, the authors prove that the radially symmetric solution develops singularities in the second order derivatives in finite time while the first order derivatives and the solution itself remain continuous and small. More precisely, it turns out that this solution is a "geometric blowup solution of cusp type", according to the terminology posed by S. Alinhac[2].

关键词： Lifespan Geometric blowup Nash-M■ser iteration