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Polylogarithms and multiple zeta values from free Rota-Baxter algebras

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Science china mathematics 2010年第9期53卷 2239-2258页

作者： GUO Li1,2.& zhang Bin3,1Center of Mathematical Sciences,Zhejiang University,hangzhou {2.,china 2.4} of mathematics and Computer Science,Rutgers University,Newark,NJ 07102.USA 3Yangtze Center of mathematics,Sichuan University,Chengdu 610064,china 1. Center of Mathematical Sciences Zhejiang University Hangzhou 310027 China2. Department of Mathematics and Computer Science Rutgers University Newark NJ 07102 USA3. Yangtze Center of Mathematics Sichuan University Chengdu 610064 China

We show that the shuffle algebras for polylogarithms and regularized MZVs in the sense of Ihara,Kaneko and Zagier are both free commutative nonunitary Rota-Baxter algebras with one *** apply these results to show that the full sets of shuffle relations of polylogarithms and regularized MZVs are derived by a single *** also take this approach to study the extended double shuffle relations of MZVs by comparing these shuffle relations with the quasi-shuffle relations of the regularized MZVs in our previous approach of MZVs by renormalization.

关键词： multiple zeta values polylogarithms Rota-Baxter algebras

An improvement in stability of delay difference systems

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Chinese Science Bulletin 1998年第7期43卷 544-547页

作者： zhang Shunian department of Applied {2., Shanghai Jiaotong University, Shanghai 2.02.0, china department of Applied mathematics Shanghai Jiaotong University Shanghai China

A new result on the stability of delay difference equations is established, in which a kind of weighted norm for x is adopted in order to estimate the upper bound of Liapunov functional.

关键词： delay difference systems uniform asymptotic stability in terms of two measures Liapunov functionals.

Discovery of Permian island-arc basalts in the Cenxi area and the tectonic significance──A piece of evidence for the paleo-Tethyan tectonic belt in western Guangdong and eastern Guangxi

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Chinese Science Bulletin 1998年第21期43卷 1838-1842页

作者： zhang Boyou 1, ZHAO Zhenhua 1, SHI Manquan 1, YANG Shufeng 2.and CHEN Hanlin 2.1. Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, china 2. {2. of Earth Sciences, Zhejiang University, hangzhou 31002., china Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China department of Earth Sciences Zhejiang University Hangzhou China

Cenxi Permian basalts are the late Palaeozoic island-arc type basalts first found in South china. REE and trace element characteristics and distribution patterns show that this volcanic formation, which has been isotopically dated at 2.1 MaB.P. by the 39Ar/ 40Ar method, is of an active continental marginal island arc type, and that the tectonic environment at that time was an island-arc marginal sea or minor ocean basin related with the paleo-Tethyan tectonic belt in western Guangdong-eastern Guangxi.

关键词： spilite-keratophyre pillow lava Permian continental margin paleo-Tethyan evolution.

Variational minimizing parabolic and hyperbolic orbits for the restricted 3-body problems Dedicated to my Teacher Professor Yang Wannian on the Occasion of his 75th Birthday

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Science china mathematics 2012年第4期55卷 721-725页

作者： zhang ShiQing department of {2. and Yangtze Center of {2.,Sichuan University,Chengdu 610064,china 1. department of mathematics and Yangtze Center of mathematics Sichuan University Chengdu 610064 China

Using variational minimizing methods,we prove the existence of the odd symmetric parabolic or hyperbolic orbit for the restricted 3-body problems with weak forces.

关键词： restricted 3-body problems variational minimizers odd parabolic orbits odd hyperbolic orbits

Mathematic Expression of Kinetic Compensation Effect and Relationship between the Exothermic Decomposition Temperature and Critical Temperature of Thermal Explosion of Eighty-six Energetic Materials

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含能材料 2001年第1期9卷 8-9页

作者： HU Rong zu 1, YANG De suo 2. zhang Jiao qiang 3 (1. department of Chemistry,Northwest University, Xi′an 710065,{2. 2. department of Chemistry and Chemical Engineering, Baoji College of Arts and Science, Baoji 72.007,{2. 3. department of 西北大学陕西西安 710065 宝鸡文理学院陕西 721007 西北工业大学陕西西安 710072

Two relationships are established using the least squares method,between the kinetic parameters (the apparent activation energy and pre exponential constant),and the exothermic decomposition temperature and ther... 详细信息

关键词： critical temperature of thermal explosion decomposition temperature DSC energetic materials.

STABILITIES OF (A,B,C) AND NPDIRK METHODS FOR SYSTEMS OF NEUTRAL DELAY-DIFFERENTIAL EQUATIONS WITH MULTIPLE DELAYS

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Journal of Computational mathematics 2003年第3期21卷 375-382页

作者： Guo-feng zhang (department of {2., Lanzhou University, Lanzhou 730000, china) department of mathematics Lanzhou University Lanzhou 730000

Consider the following neutral delay-differential equations with multiple delays (NMDDE)where γ> 0, L, Mj and Nj are constant complex- value d×d matrices. A sufficient condition for the asymptotic stability of NMDDE system (0.1) is given. The stability of Butcher's (A,B,C)-method for systems of NMDDE are studied. In addition, we present a parallel diagonally-implicit iteration RK (PDIRK) methods(NPDIRK) for systems of NMDDE, which is easier to be implemented than fully implicit RK methods. We also investigate the stability of a special class of NPDIRK methods by analyzing their stability behaviors of the solutions of (0.1).

关键词： Neutral delay differential equations (A,B,C)-method RK method Parallel diagonally-implicit iteration RK method.

EXISTENCE OF LIMIT CYCLES IN A MULTIPLY-CONNECTED REGION

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Chinese Annals of mathematics,Series B 1999年第2期20卷 169-172页

作者： zhang XIANG(department of {2., Naming Normal University, Naming 2.0097, china.) Nanjing Normal Univ Dept Math Nanjing 210097 Peoples R China

In this paper,a conjecture about the existence of limit cycles in a multiply-connected regionproposed by Ye Yanqian is proved.

关键词： Multiply-connected region Annulus theorem Limit cycle

Multiple change-points estimation of moving-average processes under dependence assumptions

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Progress in Natural Science:Materials International 2004年第8期 33-40页

作者： zhang lixin* and LI Yunxia({2. of mathematics, Zhejiang University, hangzhou 31002., china) department of mathematics Zhejiang University Hangzhou 310028 China

In this paper, some results of convergence for a least-square estimator in the problem of multiple change-points estimation are presented and the moving-average processes of ρ-mixing sequence in the mean shifts are discussed. When the number of change points is known, the consistency of change-points estimator is derived. When the number of changes is unknown, the consistency of the change-points number and the change-points estimator by penalized least-squares method are obtained. The results are also true for φ-mixing, α-mixing, associated and negative associated sequences under suitable conditions.

关键词： mean shift multiple change-points moving-average process least-squares.

Hydriding-dehydriding properties of Mg_2.i alloy modified by ball-milling in tetrahydrofuran

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Rare Metals 2004年第2期23卷 138-142页

作者： CHEN Changpin WANG Wei CHEN Yun CHEN lixin WANG Qidong department of Materials Science and Engineering, Zhejiang University{2., china department of Materials Science and Engineering Zhejiang University Hangzhou 310027 China

A new approach of ball-milled Mg_2.i in tetrahydrofuran (THF) to improve thehydriding kinetics of Mg_2.i alloy is suggested and studied. It is found that the modified alloydisplayed the improved activity for hydriding even at relatively low temperature (e.g., 32.-373 K).In the case of the sample milled in THF for 2. h, the hydrogen content (mass fraction) reaches 1.6 %at 32. K, 2.1% at 348 K and 3.4% at 448 K, respectively. The use of THF during grinding led to thechange of the structure, which is reflected by the broadening and weakening of the diffraction peaksin the XRD spectra. The XPS analysis shows that Mg (2.) binding energy peak of Mg_2.i aftermodification shifted from a lower binding energy to a higher one, indicating the charge transferencebetween Mg and THF and the formation of catalytically active electron donor-acceptor (EDA)complexes on the surface of modified Mg_2.i alloy.

关键词： metal materials Mg_2.i alloy ball-milling tetrahydrofuran hydriding-dehydriding property