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Weak martingale Hardy spaces and weak atomic decompositions

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science China Mathematics 2006年第7期49卷 912-921页

作者： HOU Youliang & REN Yanbo School of Mathematics and Statistics, Wuhan university, Wuhan 430072, China Department of Mathematics & Physics, henan university of science and technology, Luoyang 471003, China School of Mathematics and Statistics Wuhan University Wuhan China Department of Mathematics & Physics Henan University of Science and Technology Luoyang China

In this paper we define some weak martingale Hardy spaces and three kinds of weak atoms. They are the counterparts of martingale Hardy spaces and atoms in the classical martingale Hp-theory. And then three atomic decomposition theorems for martingales in weak martingale Hardy spaces are proved. With the help of the weak atomic decompositions of martingale, a sufficient condition for a sublinear operator defined on the weak martingale Hardy spaces to be bounded is given. Using the sufficient condition, we obtain a series of martingale inequalities with respect to the weak Lp-norm, the inequalities of weak (p ,p)-type and some continuous imbedding relationships between various weak martingale Hardy spaces. These inequalities are the weak versions of the basic inequalities in the classical martingale Hp-theory.

关键词： martingale, weak Hardy space, weak atom, atomic decomposition.

Optimization of thermomechanical processes in Cu-Cr-Zr lead frame alloy using neural networks and genetic algorithms

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science China(Technological sciences) 2005年第5期48卷 510-520页

作者： SU Juanhua1,2, LIU Ping2, DONG Qiming2 & LI Hejun1 1. College of Materials science and Engineering, Northwestern Polytechnical university, Xi’an 710072, China 2. College of Materials science and Engineering, henan university of science and technology, Luoyang 471003, China College of Materials science and Engineering Northwestern Polytechnical University Xi’an China College of Materials science and Engineering Henan University of Science and Technology Luoyang China

The thermomechanical treatment process is effective in enhancing the properties of the lead frame copper alloy. In this study, an optimal pattern of the thermomechanical processes for Cu-Cr-Zr was investegated using an intelligent control technique consisting of neural networks and genetic algorithms. The input parameters of the artificial neural network (ANN) are the reduction ratio of cold rolling, aging temperature and aging time. The outputs of the ANN model are the two most important properties of hardness and conductivity. Based on the successfully trained ANN model, genetic algorithms (GA) are used to optimize the input parameters of the model and select perfect combinations of thermomechanical processing parameters and properties. The good generalization performance and optimized results of the integrated model are achieved.

关键词： Cu-Cr-Zr alloy, thermomechanical processing optimization, artificial neural network, genetic algorithms.

A New Multisoliton Solution to (2+1)-Dimensional KdV Equation

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Communications in Theoretical Physics 2004年第5期41卷 669-670页

作者： PENG Yan-Ze~(1,2) 1 Department of Mathematics,Huazhong university of science and technology,Wuhan 430074,China2 Department of Mathematics and Physics,henan university of science and technology,Luoyang 471003,China Department of Mathematics Huazhong University of Science and Technology Wuhan 430074 China Department of Mathematics and Physics Henan University of Science and Technology Luoyang 471003 China

A new multisoliton solution to the(2+1)-dimensional KdV equation is obtained by means of the truncatedPainleve expansion method and a direct ansatz *** new exact solution is periodic in the propagating directionx and exponentially decaying in y and thus it is called periodic solitons.A typical spatial structure of it is illustrated bythe figures.

关键词： (2+1)-dimensional KdV equation periodic solitons truncated Painleve expansion method

Effect of Stoichiometry on Properties of Rare-Earth-Based Hydrogen Storage Alloy for Nickel-Metal Hydride Secondary Battery

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Journal of Materials science & technology 2003年第1期19卷 90-92页

作者： Quan’an LISchool of Materials science and Engineering, henan university of science and technology, Luoyang 471003, ChinaYungui CHEN and Mingjing TUDepartment of Metal Materials, Sichuan university, Chengdu 610065, China henan Univ Sci & Technol Sch Mat Sci & Engn Luoyang 471003 Peoples R China Sichuan Univ Dept Met Mat Chengdu 610065 Peoples R China

Effect of stoichiometry on microstructures, electrochemical properties and PCT characteristics of the alloys MI（Ni0.71Co0.15-Al0.06Mn0.08）x （MI=Lanthanum-rich Michmetal, x=4.6;.2） have been investigated. The lattice constants a, c, and cellvolumes of non-stoichiometric alloys are bigger than those of the stoichiometric alloy. With the increasing stoichiometry x,the value of a decreases, and the value of c and cell volume increases except for those of the stoichiometric alloy; the plateaupressure of PCT curve, discharge capacity and cycling stability all increase. The alloy with x=5.2 shows the highest dischargecapacity and the best cycling stability among the studied alloys.

关键词： Hydrogen storage alloy Metal hydride electrode Rare earth Electrochemical property Stoichiometry

Dry Friction Characteristics of Ti-6Al-4V Alloy under High Sliding Velocity

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Journal of Wuhan university of technology(Materials science) 2007年第4期22卷 582-585页

作者：邱明 School of Mechatronic Engineering Henan University of Science and Technology Theory of Lubrication and Bearing Institute Xi'an Jiaotong UniversityXi'an 710049China

Tribological behaviours of Ti-6Al-4V alloy pins sliding against GCr15 steel discs over a range of contact pressures （0.33-1.33 MPa） and sliding velocities （30-70 m/s） were investigated using a pin-on-disc tribometer under unlubricated conditions. The wear mechanisms and the wear transition were analyzed based on examinations of worn surfaces using SEM, EDS and XRD. When the velocity increases, the friction coefficient and the wear rate of the Ti-6Al-4V alloy show typical transition features, namely, the critical values of sliding velocities for 0.33 and 0.67 MPa are 60 and 40 m/s, respectively. The experimental results reveal that the tribological behaviours of Ti-6Al-4V alloys are controlled by the thermal-mechanical effects, which connects with the friction heat and hard particles of the pairs. A tribolayer containing mainly Ti oxides and V oxides is formed on the worn surface of Ti-6Al-4V alloy.

关键词： Ti alloy dry sliding friction behavior contact temperature wear mechanism

Melt-spun Al_(70-X)Si_(30)Mn_X (X=0,3,5,7,10) anode in lithium-ion batteries

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science China(Technological sciences) 2009年第8期52卷 2288-2294页

作者： SUN ZhanBo1, LI XuePeng1, WANG XiaoDong1, HU Qing1, ZHAO MingShu1, ZHU YaoMin2, LI Yan2 & SONG XiaoPing1 1 School of science, State Key Laboratory for Mechanical Behavior of Materials, Xi’an Jiaotong university, Xi’an 710049, China 2 School of Materials science and Engineering, henan university of science and technology, Luoyang 471003, China School of science State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong University

Al70-XSi30MnX (X=0, 3, 5, 7, 10, mol%) ribbons were prepared by melt spinning. A supersaturated solid solution of Si and Mn in fcc Al and some microstructures consisting of nano grains were obtained. Some alloys with nano-sized grains exhibited high discharge capacities and favorable cycle properties. The capacity of more than 400 mAh/g could be obtained in melt-spun Al67Si30Mn3 alloy after 20 cycles and more than 300 mAh/g after 40 cycles. Li/Si and Li/Al compounds in the anodes of pure Al and pure Si were not detected in Al-Si-Mn alloys inserted by Li. It is considered that the formation of the supersaturated solid solution and refinement of microstructures have prevented the alloys from the forming the compounds with superfluous Li. As a result, the electrochemical properties have been improved.

关键词： Al-Si-Mn alloy melt spinning microstructure electrochemical property

Sliding Mode Control with Disturbance Observer for a Class of Nonlinear Systems

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International Journal of Automation and computing 2012年第5期9卷 487-491页

作者： Lei-Po Liu Zhu-Mu Fu Xiao-Na Song College of Electric and Information Engineering, henan university of science and technology, Luoyang 471003, China College of Electric and Information Engineering Henan University of Science and Technology Luoyang China

This paper is concerned with the stabilization problem for a class of nonlinear systems with disturbance. The disturbance model is unknown and the first derivative of disturbance is bounded. Firstly, a general disturbance observer is proposed to estimate disturbance approximatively. Secondly, since the bound of the disturbance observer error is unknown, an adaptive sliding mode controller is designed to guarantee that the state of system asymptotically converges to zero and the unknown bound can be adjusted by an adaptive law. Finally, an example is given to illustrate the effectiveness of the proposed method.

关键词： Nonlinear systems disturbance observer adaptive sliding mode control derivative of disturbance asymptotic stability

Effects of Sb,Sm, and Sn additions on the microstructure and mechanical properties of Mg-6Al-1.2Y-0.9Nd alloy

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Rare Metals 2009年第5期28卷 516-522页

作者： LI Kejie LI Quanan JING Xiaotian CHEN Jun ZHANG Xingyuan School of Materials science and Engineering Xi ＇an University of Technology Xi ＇an 710048 China School of Materials science and Engineering Henan Universiry of Science and Technology Luoyang 471003 China

The microstructure and mechanical properties of Mg-6Al-1.2Y-0.9Nd magnesium alloy with Sb, Sm, or Sn addition were investigated through X-ray diffraction （XRD）, optical microscopy （OM）, scanning electron microscopy （SEM）, and energy dispersive spectroscopy （EDS）. The results show that small amounts of Sb, Sm, and especially Sn can refine the grains of the alloy. High melting point Sb3Y5, Al2Sm, and Nd5Sn3 intermetallic compounds can be formed respectively when Sb, Sm, and Sn are added to the alloy. Sb and Sm can improve the tensile strength of the alloy at ambient and elevated temperatures. The tensile strength of the alloy with Sm addition is the highest at 293 and 423 K. However, the tensile strength of the alloy with Sn addition is the highest at 448 K.

关键词： magnesium alloys mechanical properties microstructure Sb Sm Sn

Cloning and analysis of cross-intron genomic gene encoding ACO in Paeonia suffruticosa Andr.

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Forestry Studies in China 2012年第4期14卷 291-298页

作者： FAN Bing-you GAO Shui-pingCollege of Forestry henan university of science and technology HOU Xiao-gai SHI Guo-an KONG Xiang-sheng College of Agriculture Henan University of Science and Technology

The last step of ethylene biosynthesis in higher plants is to convert 1-aminocyclopropane-1-carboxylic acid （ACC） to ethylene by ACC oxidase （ACO）. In our investigation, a cross-introns genomic DNA gene encoding ACC oxidase, PsgACO, was isolated from Paeonia suffruticosa. It revealed that PsgACO （FJ855434） has 1281 bases, containing four exons and three introns, en- coding 312 amino acids. The four exons stretched from 1 to 105, 217 to 434, 592 to 925 and 1000 to 1281 bases. A splicing junction sequence of all the exon-introns conformed to the GT-AG rule in the cross-intron genomic DNA sequence of the ACO gene. PsgACO showed high homology to many characterized ACC oxidases both at the nucleic acid and amino acid levels. As well, twelve amino acid residues were conserved among many ACOs from other species. A phylogenetic tree analysis indicated that the amino acid of ACOs is quite conserved among the different eudicots. The phylogenetic tree showed that both the tree peony and herbaceous peony are quite isolated taxa. Bioinformatic analysis showed that the molecular weight of ACO is 35.29 kD, with a theoretical pI of 5.25. It is a non-secrete, stable hydrophilic protein, located in the cytoplasm.

关键词： Paeonia suffruticosa A CO cloning sequence analysis