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Tribological Properties of Dimpled Surface Alloying Layer on Carbon Steel

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Journal of Wuhan University of Technology(Materials Science) 2009年第2期24卷 218-222页

作者：万轶 department of Materials Science & Engineering Nanjing University of Science and Technology department of Mechanical and Electrical Engineering Yingtian College

The effect of surface structure and coating on tribological properties of 45^# carbon steel disc was analyzed. A Nd：YAG laser was used to generate rnicrodirnples on steel surfaces. Dimples with diameter of 150 rn and depth of 50 rn were distributed in an orbicular array on disc surface. Then the alloying element Mo was sputtered to 45# carbon steel disc surface by means of double glow plasma technology. Diffusion Mo alloying layer with 30min thickness and high hardness up to 0.02. was formed on the disc surface. Tribological experiments of three types samples （smooth, texturing and texturing＋alloying） were conducted with a pin-on-disc tribometer. It is found that the dimpled-samples are most effective for reducing friction in comparison with smooth steel surthces, improving the lubricating state from boundary to hydrodynamic region.

关键词： laser surface texturing double glow plasma surface alloying technology carbon steel tribological performance lubricating state

Special magnetic phenomena in heavily doped La_(0.7-x)Dy_xSr_(0.3)MnO_3 system

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Science china(Physics,Mechanics & Astronomy) 2008年第1期51卷 90-97页

作者： LIU Ning 1,2.,YAN GuoQing 1,3 ,CAI ZhiRang 1 ,PI Li 2.,ZHANG Bei 2.&TONG Wei 2.1 department of Physics,Suzhou college,Suzhou 2.4000,{2. 2.Structure Research Laboratory,University of Science and Technology of china,Hefei 2.002.,{2. 3 National Laboratory of Solid State Microstructures,Physics department,Nanjing University,Nanjing 2.0093,{2. 1. department of Physics Suzhou College Suzhou 234000 China 2. Structure Research Laboratory University of Science and Technology of China Hefei 230026 China 3. National Laboratory of Solid State Microstructures Physics Department Nanjing University Nanjing 210093 China

The magnetism in heavily Dy doped La0.7-xDyxSr0.3MnO3(0.40≤x≤0.70)system is studied in this *** M-T relation seems to be complicated with the increase of *** sample with x=0.40,AFM behavior exists at T≤TN and M-T curves under zero field cooling(ZFC)and field cooling(FC)exhibit typical behavior of spincluster glass state above *** the sample with x=0.50,the M-T curve under ZFC exhibits a valley at a low temperature while the M-T curve under FC exhibits the negative magnetization below *** samples with x=0.60,0.70,their ZFC M-T curves are similar to that of x=0.50,but the FC M-T curves do not exhibit negative values any *** the peculiar phenomena above are well explained by Néel double-lattice model combined with M-H relation at typical *** molecular field theory fits well the negative magnetization for x=0.50.

关键词： heavily doped special magnetic phenomena double-lattice model

Isoprenaline enhances local Ca2. release in cardiac myocytes

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Acta Pharmacologica Sinica 2006年第07期27卷 927-932页

作者： Jian-xin SHEN~(2.3,42.department of physiology,Shantou University medical {2.,Shantou 515041,china 3 department of physiology,medical School of Xi'an Jiaotong University,Xi'an 710061,china departmentofphysiology ShantouUniversityMedicalCollegeShantou515041China departmentofphysiology MedicalSchooloJXi'anJiaotongUniversityXi'an710061China

Aim:Contraction of cardiac myocytes is controlled by the generation and ampli-fication of intracellular Ca2.*** key step of this process is the couplingbetween sarcolemma L-type Ca2.channels（LCCs）and ryanodine receptors（RyRs）in the sarcoplasmic reticulum（SR）.β-Adrenergic stimulation is an important regu-latory mechanism for this coupling *** the details underlied the globallevel,which require local Ca2.release study are still *** present study isto explore the effects of β-adrenergic stimulation on local Ca2.***:Using confocal microscopy combined with loose-seal patch-clamp approaches,effects of isoprenaline(1 μmol·L-1),a β-adrenergic agonist,on local SR Ca2.re-lease triggered by Ca2.influx through LCCs in intact rat cardiac myocytes ***:Isoprenaline increased the intensity of ensemble averagedlocal Ca2.transients,the peak of which displayed a typical bell-shaped voltage-dependence over the membrane voltages ranging from～-40mV to～+35m ***-ther analysis showed that this enhancement could be explained by the increasedcoupling fidelity（which refers the increased probability of RyRs activation upondepolarization）,and the increased amplitude of evoked Ca2.sparks(due to moreCa2.releases through local RyRs).In addition,isoprenaline decreased the firstlatency,which displayed a typical"U"-shaped voltage-dependence,showing theavailable acceleration and synchronization of β-adrenergic stimulation on intrac-ellular calcium ***:Isoprenaline enhances local Ca2.release incardiac *** results underscore the importance of regulation of β-adrenergic stimulation on local intermolecular signals between LCCs and RyRs inheart cells.

关键词： local calcium release calcium signaling cardiac myocytes isoprenaline confocal microscopy

Orientation angle rotatability of planar serial n-link manipulators

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Science china(Technological Sciences) 2010年第6期53卷 1620-1637页

作者： LI RuiQin1,XIAO DengHong1 & DAI Jian S2.1 college of Mechanical Engineering and Automation,North University of china,Taiyuan 030051,{2. 2.department of Mechanical Engineering,King’s college London,University of London,London WC2. 2.S,UK 1. college of Mechanical Engineering and Automation North University of China Taiyuan 030051 China2. Department of Mechanical Engineering King’s College London University of London London WC2R 2LS UK

This paper presents a new method of analyzing the orientation angle rotatability of a planar serial n-link manipulator by examining the rotatability of its virtual equivalent *** orientation boundary region decomposition is proposed based on the polynomial discriminant derived from a serial three-link *** angle workspace indicates a set of angle ranges by which the end-effector can reach with certain orientation for every point in the reachable position *** introducing a virtual equivalent mechanism,the open-chain kinematic problem is converted into a close-chain mechanism,and the Grashof-type condition is used to examine the rotatability of the end-effector *** reachable position workspace can be divided into several Grashof intervals and non-Grashof intervals based on the extreme positions and singular configurations of a *** derived equations in this paper can be used to calculate the variation rule of the orientation angle workspace of any given planar serial n-link manipulator on the basis of its link *** orientation angle rotatability of a seven-link serial manipulator is solved by the proposed method and graphical representations of the orientation angle workspaces are mapped onto a three-dimensional coordinate *** theoretical approach has practical significance for the design of a highly dexterous serial n-link manipulator with proposed link relations.

关键词： Grashof criterion planar serial manipulator orientation angle workspace virtual equivalent mechanism

Piecewise-Koszul algebras

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Science china Mathematics 2007年第12期50卷 1795-1804页

作者： Jia-feng L■~1 Ji-wei HE~2.Di-ming LU~(1+) ~1 department of Mathematics,Zhejiang University,Hangzhou 31002.,china ~{2. of Mathematics,Shaoxing college of Arts and Sciences,Shaoxing 312.00,china department of Mathematics Zhejiang University Hangzhou 310027 China department of Mathematics Shaoxing College of Arts Sciences Shaoxing 312000 China

It is a small step toward the Koszul-type *** piecewise-Koszul algebras are, in general,a new class of quadratic algebras but not the classical Koszul ones,simultaneously they agree with both the classical Koszul and higher Koszul algebras in special *** give a criteria theorem for a graded algebra A to be piecewise-Koszul in terms of its Yoneda-Ext algebra E(A),and show an A_∞-structure on E(A).Relations between Koszul algebras and piecewise-Koszul algebras are *** particular,our results are related to the third question of Green-Marcos.

关键词： (d-)Koszul algebras A_∞-algebras Yoneda-Ext algebras

Kinetics and mechanism of the reaction between thiourea and iodate in unbuffered medium

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Science china Chemistry 2004年第6期47卷 480-487页

作者： WANG Shun1,2. LIN Juanjuan1, CHEN Fan1, HU Maolin1, HU Xingen1, HAN Yiping1 & GAO Qingyu2.1.department of Chemistry and Material Science, Wenzhou Normal college, Wenzhou 32.02.,{2. 2. college of Chemical Engineering,{2. University of Mining and Technology, Xuzhou 2.1008,{2. 1. department of Chemistry and Material Science Wenzhou Normal College 325027 Wenzhou China 2. college of Chemical Engineering China University of Mining and Technology 221008 Xuzhou China

The reaction between iodate and thiourea has been studied in an unbuffered acidic medium. In excess iodate the reaction shows not only oligooscillations in pH, Pt potential and the concentration of iodide ion, [I?], but also an initial induction period which has the linear relation with initial pH. At the end of the induction period, [I?] decreases sharply and a yellow coloration (due to iodine) appears transiently. While in excess thiourea iodine is produced and finally con- sumed, leaving milky deposits (due to sulfur) at the end of the reaction. The induction period from the start of the reaction to the maximum of [I2. is also directly proportional to initial pH. A 14-step mechanism, including a H+-mediated preequalibrium, Dusman reaction, iodine-sulfur reactions and sulfur-sulfur reactions, is proposed. Computer simulations using this mechanism give good agreement with experiments.

关键词： oligooscillations, pH dynamics, thiourea, iodate, complex reaction mechanism, dynamic simulation.

A Type II Diabetic Model-from Insulin Resistance to Diabetes

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生物医学工程学杂志 2005年第S1期22卷 43-44页

作者： Yong WU~(1,2. Jing-Ping OU YANG~1 Jing-Fang ZHANG~1 Ke WU~11(department of Pathophysiology, {2. college of Wuhan University, Wuhan 430071, china)2.department of physiology, Hubei college of Traditional Chinese Medicine, Wuhan 430061, china)

The spectrum of path factorization of bipartite multigraphs

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Science china Mathematics 2007年第7期50卷 1045-1054页

作者： Jian WANG~1 Bei-liang DU~(2.) 1 Nantong Vocational college,Nantong 2.6007,china {2. of Mathematics,Suzhou University,Suzhou 2.5006,china 1. Nantong Vocational college Nantong 226007 China 2. department of Mathematics Suzhou University Suzhou 215006 China

Let λK m,n be a bipartite multigraph with two partite sets having m and n vertices, respectively. A P v-factorization of λK m,n is a set of edge-disjoint P v-factors of λK m,n which partition the set of edges of λK m,n . When v is an even number, Ushio, Wang and the second author of the paper gave a necessary and sufficient condition for the existence of a P v-factorization of λK m,n . When v is an odd number, we have proposed a conjecture. Very recently, we have proved that the conjecture is true when v = 4k ? 1. In this paper we shall show that the conjecture is true when v = 4k + 1, and then the conjecture is true. That is, we will prove that the necessary and sufficient conditions for the existence of a P 4k+1-factorization of λK m,n are (1) 2.m ? (2. + 1)n, (2. 2.n ? (2. + 1)m, (3) m + n ≡ 0 (mod 4k + 1), (4) λ(4k + 1)mn/[4k(m + n)] is an integer.

关键词： bipartite multigraph factorization 05B30 05C70

EXACT EXPLICIT SOLUTIONS OF THE NONLINEAR SCHRDINGER EQUATION COUPLED TO THE BOUSSINESQ EQUATION

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Acta Mathematica Scientia 2003年第4期23卷 453-460页

作者：姚若侠李志斌 department of Computer Science Weinan Teachers' College Weinan 714000 China department of Computer Science East China Normal University Shanghai 200062 China

A system comprised of the nonlinear Schrodinger equation coupled to the Boussinesq equation (S-B equations) which dealing with the stationary propagation of coupled non-linear upper-hybrid and magnetosonic waves in magnetized plasma is proposed. To examine its solitary wave solutions, a reduced set of ordinary differential equations are considered by a simple traveling wave transformation. It is then shown that several new solutions (either functional or parametrical) can be obtained systematically, in addition to rederiving all known ones by means of our simple and direct algebra method with the help of the computer algebra system Maple.

关键词： Coupled Schrodinger-Boussinesq equations traveling wave transformation Riccati equations solitary wave solution