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Synthesis of α-[2-(2, 4-Dichlorophenoxy) Propionyloxy] Alkyl Phosphonates

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Chinese Chemical Letters 1997年第11期8卷 943-944页

作者： Jun WANG Hong Wu HE and Zhao Jie LIU(institute of Organic Synthesis, Central china Normal University, Wuhan, 43.070)(department of Chemistry, Xiaogan Teachers College,{3., 43.100) Cent china Normal Univ Inst Organ Synth Wuhan 430070 Peoples R China Xiaogan Teachers Coll Dept Chem Hubei 432100 Peoples R China

The synthesis of thirteen new compounds α - [2 - (2, 4 -dichlorophenoxy) propionyloxy] alkyl phosphonates was described. The structures of these compounds were characterized by IR, 1H-NMR and MS.

关键词： Synthesis of Propionyloxy Dichlorophenoxy Alkyl Phosphonates

Relationships between bacterial-algal proliferating and mass extinction in the Late Devonian Frasnian-Famennian transition:Enlightening from carbon isotopes and molecular fossils

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Science china Earth Sciences 2005年第10期48卷 1656-1665页

作者： GONG Yiming1,2, XU Ran1, TANG Zhongdao1, SI Yuanlan3.& LI Baohua4 1. Faculty of Earth Science and State Key Laboratory of Geological Processes and Mineral Resources, china University of Geosciences, Wuhan 43.074, china 2. institute of Resources & Environments, Henan Polytechnic University, Jiaozuo 454003. china 3. department of Computer Science, South-Central University for nationalities, Wuhan 43.074, china 4. Laboratory of Marine Geology, Tongji University, Shanghai 200092, china Faculty of Earth Science and State Key Laboratory of Geological Processes and Mineral Resources china University of Geosciences Wuhan china institute of Resources & Environments Henan Polytechnic University Jiaozuo china department of Computer Science South-Central University for nationalities Wuhan china Laboratory of Marine Geology Tongji University Shanghai china

Studies show positive shifts of inorganic and organic carbon isotope values (δ 13.carb and δ 13.kerogen) from +0.43.(‰ V-PDB) to +3.54 (‰ V-PDB) and from ?29.3. (‰ V-PDB) to ?24.14 (‰ V-PDB), respectively, B* (Ba* = Ba/ (Al2O3.X 15%)) values from 0.015 to 0.144, TOC values from 0.02% to 0.21%, V/Cr values from 0.3.to 2.0, Sr/Ba values from 3.20 to 49.50 in the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone of the Yangdi sec-tion deposited in carbonate slope facies of Guilin, Guangxi, South china, which indicates that biomass, productivity, organic carbon burial and salinity increase and that oxygenation near the boundary between sediments and waters decreases from the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone. Abundance of molecular fossils increases and normal alkanes, isoprenoid hydrocarbon, terpanes and steranes are dominated from the Late Devonian Frasnian to the bottom of Famennian, which shows that the predecessors of molecular fossils of the Frasnian-Famennian (F-F) transition are dominated by marine phytoplankton, zooplankton and benthic bacteria with no photosynthesis. Therefore, it is considered that the F-F transitional mass extinction with a multistage, selection and global synchronizing was caused by bacte-rial-algal proliferating, continuing deterioration of the shallow marine ecoenvironment of the mid-dle-lower latitudes. A simple cause and effect chain can be expressed as: appearance of seed plants and multi-storied forests → enhanced chemical and biochemical weathering and pe-dogenesis → wide development of soils → increasing riverine nutrient fluxes in epicontinental sea → from superoligotrophic to eutrophic in epicontinental sea → proliferating of marine phyto-plankton and zooplankton → frequent red tide and anoxia → mass extinction of shallow marine organisms in the middle-lower latitudes. It is worth notice that the factor drawdown of atmos-pheric Pco2, climatic cooling and sea level falling c

关键词： mass extinction, bacteria-algae, carbon isotopes, molecular fossils, biodiversity, Late Devonian, Guangxi, South china.

ON THE HYPER ORDER OF SOLUTIONS OF HIGHER ORDER DIFFERENTIAL EQUATIONS

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Chinese Annals of mathematics,Series B 2003年第4期24卷 501-508页

作者： CHEN ZONGXUAN department of mathematics, Jiangxi Normai University, Nanchang 3.0027, china. {3. of mathematics, Academy of mathematics and System Sciences, Chinese Academy of Sciences, Beijing 100080, china. Jiangxi Normal Univ Dept Math Nanchang 330027 Peoples R China Chinese Acad Sci Acad Math & Syst Sci Inst Math Beijing 100080 Peoples R China

The author investigates the hyper order of solutions of the higher order linear equation, andimproves the results of M. Ozawa[15], G. Gundersen[6] and J. K. Langley[12].

关键词： Differential equation Entire function Hyper order

A study of two-dimensional magnetic polaron

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Science china(Physics,Mechanics & Astronomy) 2006年第4期49卷 421-429页

作者： LIU Tao1, ZHANG Huaihong1, FENG Mang1,2 & WANG Kelin1,3.1. School of Science, Southwest University of Science and Technology, Mianyang 621010, china 2. Wuhan institute of Physics and mathematics, Chinese Academy of Sciences, Wuhan 43.070, china 3. department of Modern Physics, University of Science and Technology of china, Hefei 23.026, china School of Science Southwest University of Science Technology Mianyang 621010 China Wuhan institute of Physics mathematics Chinese Academy of Sciences Wuhan 430070 China department of Modern Physics University of Science Technology of china Hefei 230026 China

By using the variational method and anneal simulation, we study in this paper the self-trapped magnetic polaron (STMP) in two-dimensional anti-ferromagnetic material and the bound magnetic polaron (BMP) in ferromagnetic material. Schwinger angular momentum theory is applied to changing the problem into a coupling problem of carriers and two types of Bosons. Our calculation shows that there are single-peak and multi-peak structures in the two-dimensional STMP. For the ferromagnetic material, the properties of the two-dimensional BMP are almost the same as that in one-dimensional case; but for the anti-ferromagnetic material, the two-dimensional STMP structure is much richer than the one-dimensional case.

关键词： self-trapped magnetic polaron, bound magnetic polaron, impurity potential, anti-ferromagnet.

A lumped mass finite element method for vibration analysis of elastic plate-plate structures

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Science china mathematics 2010年第6期53卷 1453-1474页

作者： LAI JunJiang1,HUANG JianGuo2,3.& SHI ZhongCi4 1department of mathematics,Minjiang University,Fuzhou 3.0108,china 2department of mathematics,Shanghai Jiao Tong University,Shanghai 200240,china 3.ivision of Computational Science,E-institute of Shanghai Universities,Shanghai Normal University,Shanghai 20023.,china 4institute of Computational mathematics,Academy of mathematics and Systems Science,Chinese Academy of Sciences,Beijing 100190,china 1. department of mathematics Minjiang University Fuzhou 350108 China2. Department of Mathematics Shanghai Jiao Tong University Shanghai 200240 China3. Division of Computational Science E-Institute of Shanghai Universities Shanghai Normal University Shanghai 200234 China4. Institute of Computational Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China

The fully discrete lumped mass finite element method is proposed for vibration analysis of elastic plate-plate *** the space directions,the longitudinal displacements on plates are discretized by conforming linear elements,and the transverse displacements are discretized by the Morley *** means of the second order central difference for discretizing the time derivative and the technique of lumped masses,a fully discrete lumped mass finite element method is obtained,and two approaches to choosing the initial functions are also *** error analysis for the method in the energy norm is established,and some numerical examples are included to validate the theoretical analysis.

关键词： vibration analysis plate-plate structures lumped mass FEM error analysis

K-uniformly rotund spaces and k-uniformly smooth spaces

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Chinese Science Bulletin 1998年第2期43卷 92-95页

作者： Suyalatu 1 and WU Congxin 2 1. department of mathematics,Inner Mongolia Normal University, Huhhot 010022, china 2. department of mathematics, Harbin institute of Technology, Harbin 150006, china department of mathematics Inner Mongolia Normal University Huhhot China department of mathematics Harbin Institute of Technology Harbin China

The conception of k_uniform smoothness (KUS) is introduced. It is the extension of the conception of uniform smoothness. It is proved that the k_uniform smoothness and Sullivan’s K_uniform rotundity (KUR) are the daul notions. X+* is a KUR space if and only if X is a KUS space, X+* is a KUS space if and only if X is a KUR space. If X is a KUS space, then X is a (K+1)US space. It is also proved that the KUS space includes the Nan’s k_strongly smooth space.

关键词： K_uniform smoothness K_uniform convexity.

Solving the input data in error correc-tion of optical fabrication by finite Fourier coefficient algorithm

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Science china(Technological Sciences) 2006年第1期49卷 50-60页

作者： CHENG Haobo1,2, SUN Guozheng3.& FENG Zhijing2 1. department of Optical Engineering, Beijing institute of Technology, Beijing 100081, china 2. department of Precision Instruments and Mechanology, Tsinghua University, Beijing 100084, china 3. china North Industries Group Corporation, Beijing 100089, china 1. department of Optical Engineering Beijing Institute of Technology Beijing 100081 China 2. department of Precision Instruments and Mechanology Tsinghua University Beijing 100084 China 3. china North Industries Group Corporation Beijing 100089 China

A free-form lens (FFL) is a special surface that is difficult to be fabricated. FFL are usually fabricated by computer-controlled optical surfacing (CCOS) technique. During CCOS, the material removal amount is determined by the unit removal function (URF) convoluting with the input data――the dwell time. When the removal amount and the URF are known, how to solve the input data involves the special algorithm――deconvolution. Usually, the input data are solved by virtue of low pass filter or iterative methods. However, an approximation solution would destroy the machining stability nec-essary to perform precisely CCOS. In this paper, to solve the input data, a new method that is based on the finite Fourier coefficient is put forward. It can give a continuous and accurate solution for fabricating choice. Several parameters are simulated, which influ-ence the process of CCOS, and evaluating on the effect of the method is also carried out. Experimental results verify that this method is suitable for guiding the manufacturing of high precision FFL.

关键词： optical fabrication, computer controlled optical surfacing, free-form lens, finite Fourier coefficient, error correction.

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鄂西南山区野生观赏植物资源及其园林应用

山地农业生物学报 2001年第2期20卷 117-123,127页

作者：赵小兰湖北民族学院园艺系湖北恩施445000

通过野外调查并综合前人的报道 ,列出了鄂西南山区野生观赏植物 97科 2 2 6属 3.5种的名录并根据观赏习性将其园林用途分为 :孤植树类、行道树类、林丛类、花灌木类、垂直绿化类、地被类、绿篱类、盆景类、切花类、花坛、花境类、盆花... 详细信息

通过野外调查并综合前人的报道 ,列出了鄂西南山区野生观赏植物 97科 2 2 6属 3.5种的名录并根据观赏习性将其园林用途分为 :孤植树类、行道树类、林丛类、花灌木类、垂直绿化类、地被类、绿篱类、盆景类、切花类、花坛、花境类、盆花类、水 (湿 )生观赏植物类等十二大类。对于其中观赏特性及开发利用价值突出的植物种类进行了重点描述。通过对鄂西南山区野生观赏植物资源的调查与研究 ,将为其保护性开发利用打下基础 ,最终为中西部地区创建生态园林。

关键词：鄂西南地区园林植物野生植物资源园林应用资源调查观赏植物

Transitivity, mixing and chaos for a class of set-valued mappings

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Science china mathematics 2006年第1期49卷 1-8页

作者： LIAO Gongfu, WANG Lidong & ZHANG Yucheng institute of mathematics, Jilin University, Changchun 13.012, china institute of Nonlinear Information Technology, Dalian Nations University, Dalian 116600, china department of mathematics, University of Science and Technology of china, Hefei 23.026, china 1. institute of mathematics Jilin University Changchun 130012 China 2. institute of Nonlinear Information Technology Dalian Nations University Dalian 116600 China 3. department of mathematics University of Science and Technology of China Hefei 230026 China

Consider the continuous map f : x → X and the continuous map f of K,(X) into itself induced by f, where X is a metric space and K(X) the space of all non-empty compact subsets of x endowed with the Hausdorff metric. According to the questions whether the chaoticity of f implies the chaoticity of f posed by Roman-Flores and when the chaoticity of f implies the chaoticity of f posed by Fedeli, we investigate the relations between f and f in the related dynamical properties such as transitivity, weakly mixing and mixing, etc. And by using the obtained results, we give the satisfied answers to Roman-Flores's question and Fedeli's question.

关键词： set-valued mapping, transitivity, weak mixing, mixing, chaos.