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THE NEAR-CRITICAL AND SUPER-CRITICAL ASYMPTOTIC BEHAVIOR IN THE THERMODYNAMIC LIMIT OF REVERSIBLE RANDOM POLYMERIZATION PROCESSES

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Acta Mathematica Scientia 2000年第3期20卷 380-389页

作者：韩东 univ xinjiang Dept Math Urumqi 830046 Peoples R China

In this paper, the near-critical and super-critical asymptotic behavior of a reversible Markov process as a chemical model for polymerization was studied. The results of the present paper, together with an analysis of the sub-critical stage, establish the existence of three distinct stages (sub-critical, near-critical and super-critical stages) of polymerization (in the thermodynamic limit as N --> +infinity,),depending on the value of strength of the fragmentation reaction. These three stages correspond to the size of the largest length of polymers of size N to be itself of order log N, Nm/m+1 (m greater than or equal to 2, m not equal 4n, n greater than or equal to 1) and N, respectively.

关键词： polymerization Markov process limit behavior stationary distribution

SUBCRITICAL　ASYMPTOTIC　BEHAVIOR　IN　THE　MODIFIED　LUSHNIKOV　PROCESS　OF　POLYMERIZATION

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Acta Mathematica Scientia 1996年第4期16卷 412-420页

作者：韩东 univ xinjiang DEPT MATHURUMQI 830046PEOPLES R CHINA

We consider a modified Lnshnikov process as a model of a chemical polymer ization anf study the asymptotic behavior (in the thermodynamic limit;as N →∞)of a particular probability distribution on the set of N-dimensional vectors,tile kth component of which is the number of *** study study establisles the existence of three stages (subcritical,near-critical and supercritical stages)of polymerization,dependenting upon the ratio of association and dissociation rates of f *** present paper concentrates on the analysis of tile subcritical *** the *** we show that tile size of the largest length of polymers of stize N is of the *** N as N →+∞.

关键词： Polymerization Markov process limit behavior stationary distribntion.

THE　CONSTANT　PHASE　ELEMENT　(CPE)　ON　MnO_2　ELECTRODE

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Chinese Chemical Letters 1996年第5期7卷 457-458页

作者： Guo, Y Xia, X xinjiang univ DEPT CHEMURUMQI 830046PEOPLES R CHINA

Abstract: Ac impedance responses of electrolytic manganese dioxide (EMD) electrode are measured with EIS. It was found that the impedance responses are consistent with the constant phase element (CPE)form and calculat... 详细信息

关键词： MnO2 CPE CONSTANT ELECTRODE ELEMENT ON

ON A REACTION DIFFUSION SYSTEM OF COMPETING PREDATORS

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Acta Mathematica Scientia 1990年第1期10卷 101-110页

作者：杨志平 xinjiang univ DEPT MATHURUMUQIPEOPLES R CHINA

This paper is concerned with the existence-uniqueness and the asymptotic behavior of the solution of a coupled system of reaction diffusion equations which arose from biochemistry. Under Diricblet boundary condition, the existence and the bifurcation of nonegative steady-state solutions of the system will be studied. The principal methods used in this paper are the monotone method ond the topological degree method.

关键词： topological concerned asymptotic monotone uniqueness bifurcation biochemistry proof 二七十贵

Synthesis of CuO nanometer powder by one step solid state reaction at room temperature

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Chinese Science Bulletin 1998年第7期43卷 571-573页

作者： Dianzeng Jia Jianqun Yu Xi Xia xinjiang univ Dept Chem Urumqi 830046 Peoples R China

Copper oxide nanometer powder was synthesized by one step solid state reaction of CuCl-2·2H-2O with NaOH at room temperature. The solid product CuO was characterized by X-ray diffraction and a transmission electron microscope. It has been found that the particles of prepared copper oxide are spherical with average diameter of 20 nm. This new method has the advantages of convenience and high yield compared with literature methods.

关键词： solid state reaction nanometer powder copper oxide.

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Chemical Research in Chinese universities 2001年第2期17卷 212-218页

作者： GUO Ming and LIU Wen-jie (Department of Basic Courses, Tarim university of Agricultural Reclamation, Alar, xinjiang 843300, P. R. China) Tarim univ Agr Reclamat Dept Basic Courses Alar 843300 Xinjiang Peoples R China

The molecular similarity of 139 organic compounds was calculated by the topologic index method, the flexible super-ball algorithm was used to scan similar molecules and structures. The results show that the properti... 详细信息

关键词： Molecular similarity Super-ball algorithm Calculation

Stereoselective　Syntheses　of　Some　β-D-1-Thioglycopyranosides　and　Bis(β-D-glycopyranosyl)　Sulfides　by　Phase　Transition　Catalysis

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Chemical Research in Chinese universities 1997年第1期13卷 23-28页

作者： YU Jian xin, LIU Fang min, SUN Wan fu and LIU Yu ting (Department of Chemistry, xinjiang university, Ulumuqi, 830046) xinjiang univ DEPT CHEMULUMUQI 830046PEOPLES R CHINA

The present paper covers the stereoselective syntheses of four 1 thiogalactopyranosides 1—4 and three thio disaccharides 5—7 through the PTC methods and their structures confirmed by means of elementary analysis, ... 详细信息

关键词： Synthesis Phase transition catalysis Thiogalactopyranoside Thio disaccharide Stereospecificity

Effects Of Ultrasound On Voltammetric Measurements At An Ag Cylinder Electrode

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Chinese Chemical Letters 1998年第7期9卷 663-666页

作者： Xiao Gang ZHANG Wan Yong ZHOU Chao Ying GENG Xi XIA (Institute of Applied Chemistry, xinjiang university, Wulumqi 830046) xinjiang univ Inst Appl Chem Wulumqi 830046 Peoples R China

In this paper,the voltammetric behaviours of Ag cylinder electrode in 1 mol/dm(3) KOH solution have been investigated in the presence of ultrasound irradiation. The results based on the CV, EIS and polarization measurements showed that ultrasound could enhance the mass transport, inhibit the oxygen evolution and increase the exchange current.

关键词： sonoelectrochemistry ultrasound irradiation Ag electrode voltammetric behaviours

Landscape eco-environment risk assessment of highway in arid area of xinjiang,China

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Journal of Arid Land 2010年第1期2卷 20-25页

作者： Qian, YiBing Zhou, HuaRong Wu, ZhaoNing Chinese Acad Sci Xinjiang Inst Ecol & Geog Urumqi 830011 Peoples R China xinjiang univ Coll Geol & Explorat Engn Urumqi 830046 Peoples R China

With the aid of analyses to landscape ecology in the highway region of the arid area in xinjiang of China, vegetation type, soil type and land-use type were ascertained as environmental factors of highway landscape ecosystem fragility, and seasonal flood, blown-wind sand and alkali-salinization as disaster factors of highway engineering. All items of these factors constitute an objective hierarchy of evaluating landscape ecosystem risk of the highway region in the arid area. The weighted values of the items were determined according to the number of occupied area or length by them against each unit. The area or length was interpreted with the aids of GIS technology and gained by measuring in the highway reconnaissance. The results of the eco-environmental risk assessment of G315 Yitunbulake-Qiemo section in xinjiang shows that eight units of landscape ecology can be sorted into four categories according to the differences of the fragility indices (Σxiwi) and the disaster indices (Σyiwj).

关键词： highway of arid area landscape eco-environment risk assessment