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CURVILINEAR PATHS AND TRUST REGION METHODS WITH NONMONOTONIC BACK TRACKING TECHNIQUE FOR UNCONSTRAINED OPTIMIZATION

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Journal of Computational Mathematics 2001年第3期19卷 241-258页

作者： De-tong Zhu (Department of Mathematics, shanghai Normal university, shanghai 2.02.4, china) 上海师范大学上海 200234

Focuses on a study which examined the modification of type approximate trust region methods via two curvilinear paths for unconstrained optimization. Properties of the curvilinear paths; Description of a method which combines line search technique with an approximate trust region algorithm; Information on the convergence analysis; Details on the numerical experiments.

关键词： curvilinear paths trust region methods nonmonotonic technique unconstrained optimization

Localization of genes for lateral branch and female sex expression and construction of a molecular linkage map in cucumber (Cucumis sativus L.) with RAPD markers

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Progress in Natural Science:Materials International 2005年第2期15卷 48-53页

作者： LI Xiaozun1*, PAN Junsong1*, WANG Gang1, TIAN Libo3, SI Longting3, WU Aizhong2.* and CAI Run1**(1. Agriculture and Biology School, shanghai Jiaotong {2., shanghai 2.1101, china 2. shanghai Academy of Agricultural Science, shanghai 2.1106, china 3. Horticulture School, Shenyang Agricultural {2., Shenyang 110161, china) Agriculture and Biology Sch. Shanghai Jiaotong Univ. Shanghai 201101 China Horticulture Sch. Shenyang Agricultural Univ. Shenyang 110161 China shanghai Acad. of Agric. Sci. Shanghai 201106 China

A cucumber (Cucumis sativus L.) molecular linkage map, including 79 random-amplified polymorphic DNAs (RAPD) and two genes , lb for lateral branch and f for female sex expression, is constructed from a cross between a line, S52. with weak lateral growing ability and staminate from Dabieshan Mountains area in china and another line, S06, with strong lateral growing ability and gynoecious from Europe. The map contains nine linkage groups and spans 1110.0 cM with an average distance of 13.7 cM between loci. The lb locus is located in a longer linkage group LG-2.and flanked by two markers, OP-Q5-1 and OP-M-2.2. at 9.3 cM and 15.9 cM, respectively. In the meantime, the RAPD loci, OP-Q5-2.and BC151, in a short linkage group were found to flank f at 13.7 cM and 13.4 cM, respectively. The construction of RAPD map has paved a way for further study of the genes for lateral branch, female sex expression and other agronomic traits in cucumber.

关键词： cucumber (Cucumis sativus L.) lateral branch gynoecy RAPD genetic mapping

SIMULATION OF NON-POINT POLLUTANTS EVOLUTION IN COASTAL PLAIN ISLAND-A CASE STUDY OF CHONGMING ISLAND

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Journal of Hydrodynamics 2008年第2期20卷 246-253页

作者： YIN Hai-long JIANG Wen-yan LI Jian-hua College of Environmental Science and Engineering Tongji University Shanghai 200092 China Department of Environmental Science East China Normal University Shanghai 200063 China

The coastal plain region usually shows the agricultural dominated industry mode, so more and more attention is paid to non-point pollutants discharge. In this study, the method for assessing the influence of non-point pollutants discharge on river water quality is probed which is concluded as follows：（1） Considering the costal plain island is characterized as nearly even elevation, the conventional gravitational runoff confluence method based on eight-point gravitational flowing directions （DS） is unable to compute the runoff confluence received by the surrounding rivers, so a new method of triangular confluence based on three-points of grid center and the river segments is presented. Further the equations of non-point pollutants loads estimation and non-point pollutants confluence on rivers are presented. （2. The integration mode of non-point pollutants model and river water quality model is presented so as to further assess the non-point pollutants contribution to river water quality. （3） With the Chongming Island, the third largest island in china, as an example, the above-mentioned equations are specified. For this island, the non-point pollutants loads are estimated and linked to the developed water quality model of the river network in the island, and further the non-point pollution evolution in river network is simulated. In this scenario, the non-point pollution contribution to river water quality over the whole island is clearly displayed, and the area where the river water quality is seriously influenced by non-point pollutants discharge is distinctly depicted. This scenario also shows the water quality contribution ratio of non-point pollution to point pollution can be in the range of 55.5% to 44.5% which proves the importance of non-point pollution control in costal plain islands.

关键词： non-point pollution runoffconfluence water quality model Chongming Island

Kinetic theory of self-condensing vinyl polymerization

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Science china Chemistry 2010年第12期53卷 2429-2439页

作者： ZHOU ZhiPing 1 & YAN DeYue 2.1 School of Materials Science and Engineering,Jiangsu university,Zhenjiang 2.2.13,china 2.School of Chemistry and Chemical Engineering,{2. Jiao Tong university,{2. 2.02.0,china School of Materials Science and Engineering Jiangsu University Zhenjiang China School of Chemistry and Chemical Engineering Shanghai Jiao Tong University Shanghai China

This review introduces the kinetic theory of self-condensing vinyl polymerization (SCVP),including the SCVP of AB inimers,the SCVP with non-equal reactivity between A and B groups,the SCVP in the presence of a small amount of multifunctional initiators,also the SCVP of both inimers and *** analytical expressions of various molecular parameters for the resulting hyperbranched polymers,such as the molecular size distribution function,the average molecular weight,the polydispersity index and the degree of branching,are reviewed systematically.

关键词： kinetic theory self-condensing vinyl polymerization (SCVP) hyperbranched polymers

Potential energy surfaces for low-lying electronic states of SO_2

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Science china Chemistry 2006年第4期49卷 289-295页

作者： LI Anyang1, SUO Bing2. WEN Zhenyi2.& WANG Yubin2.1. Shanxi Key Laboratory of Physico-inorganic Chemistry, Department of Chemistry, Northwest university, Xi’an 710069, china 2. Institute of Modern Physics, Northwest university, Xi’an 710069, china Shanxi Key Laboratory of Physico-inorganic Chemistry Department of Chemistry Northwest University Xi’an China Institute of Modern Physics Northwest University Xi’an China

The potential energy surfaces for the nine low-lying electronic states of SO2.have been constructed by using the multi-reference second order perturbation theory (MRPT2. with the basis set cc-pVTZ. The optimized geometries and the adiabatic excitation energies of these states are in good agreement with experiments and previous calculations. The crossings and avoided crossings dis- played in the potential energy surfaces are expounded.

关键词： cross of PES, MRPT2. SO2 (sulfur dioxide).

Geochemical and isotopic imprints of hydrodynamic environments of fissure waters in crystalline rocks

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Chinese Science Bulletin 1997年第9期42卷 756-761页

作者： WANG Yanxin and Khaustov Alexander P.1. china university of Geosciences, Wuhan 430074, china 2. Russian university of People’s Friendship, Moscow, Russia china university of Geosciences Wuhan China Russian university of People’s Friendship Moscow Russia

IN recent years,world-wide researches in relation to geologic disposal of nuclear wastes,ore-forming process modelling and ultradeep geologic drilling have been carried out in areas of crys-talline rocks,and,as a resu... 详细信息

关键词： crystalline rocks hydraulic continuity hydrochemistry isotopes.

A MODIFIED LEVENBERG-MARQUARDT ALGORITHM FOR SINGULAR SYSTEM OF NONLINEAR EQUATIONS

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Journal of Computational Mathematics 2003年第5期21卷 625-636页

作者： Jin-yan Fan (Department of Mathematics, shanghai Jiaotong university, shanghai 2.02.0, china) Department of Mathematics Shanghai Jiaotong University 上海 200240

Based on the work of paper [1], we propose a modified Levenberg-Marquardt algoithm for solving singular system of nonlinear equations F(x) = 0, where F(x) : Rn - Rn is continuously differentiable and F'(x) is Lipschitz continuous. The algorithm is equivalent to a trust region algorithm in some sense, and the global convergence result is given. The sequence generated by the algorithm converges to the solution quadratically, if ||F(x)||2.provides a local error bound for the system of nonlinear equations. Numerical results show that the algorithm performs well.

关键词： Singular nonlinear equations Levenberg-Marquardt method Trust region al- gorithm Quadratic convergence.

DISSIPATIVITY AND EXPONENTIAL STABILITY OF θ-METHODS FOR SINGULARLY PERTURBED DELAY DIFFERENTIAL EQUATIONS WITH A BOUNDED LAG

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Journal of Computational Mathematics 2003年第6期21卷 715-726页

作者： Hong-jiong Tian (Department of Mathematics, shanghai Normal university, shanghai 2.02.4, china) department of Mathematics Shanghai Normal University 上海 200234

This paper deals with analytic and numerical dissipativity and exponential stability of singularly perturbed delay differential equations with any bounded state-independent lag. Sufficient conditions will be presented to ensure that any solution of the singularly perturbed delay differential equations (DDEs) with a bounded lag is dissipative and exponentially stable uniformly for sufficiently small ε > 0. We will study the numerical solution defined by the linear θ-method and one-leg method and show that they are dissipative and exponentially stable uniformly for sufficiently small ε > 0 if and only if θ = 1.

关键词： Singular perturbation θ-methods Dissipativity Exponential stability.

Preparation and Magnetic Properties of Mn-Zn Ferrites by the Co-precipitation Method

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Journal of Wuhan university of Technology(Materials Science) 2009年第6期24卷 875-878页

作者：李雪张俊喜 School of Environmental and Chemical Engineering Shanghai University Electrochemical Research Group Shanghai University of Electric PowerKey Laboratory of State Power Corporation of China

Mn-Zn ferrites （Mn1-xZnxFe2.4） with different compositions were prepared by the coprecipitation method, and the influences of such synthesis conditions as pH value, composition and volume ratio （R） of the mixed solution and NH4HCO3 solution on their microstructures and magnetic properties were discussed. The samples were characterized by X-ray diffraction （XRD） and magnetization measurement instrument. Lattice parameters and average crystalline size of the synthesized materials were calculated from the corresponding XRD patterns with the related software Jade.5. For samples of different pH values, only one phase was found when pH values were 7.0, 8.0 and 9.0. The sample with pH value of 7.0 exhibited the highest saturation magnetic induction, the lowest coercive force, and crystallized best. For samples of different R values with pH value of 7.0, only one phase was observed in all samples, and the sample with R value of 2.3 exhibited the highest saturation magnetic induction and the lowest coercive force. The composition has mainly afected the magnetic properties, and the saturation magnetic induction increases with the increase of the content of Zn （x）, but decreases when x is beyond 0.6. The trend of coercive force is on the contrary. However, no magnetism is exhibited when the x value is up to 0.8.

关键词： co-precipitation method microstructure magnetic property Mn-Zn ferrite