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数据采集与处理 2003年第1期18卷 44-48页

作者：吕岗陈小平谭得健苏州大学电子信息学院苏州215021 中国矿业大学信电学院徐州221008

基于信息熵的免疫算法存在计算复杂 ,设置的参数需要凭经验调节和含有冗余的计算信息而导致算法收敛速度慢的缺点 ,通过对免疫抗体定义的改进 ,本文提出了一种基于矢量距的改进免疫算法并证明了它的全局收敛性。多峰函数优化问题的测试... 详细信息

基于信息熵的免疫算法存在计算复杂 ,设置的参数需要凭经验调节和含有冗余的计算信息而导致算法收敛速度慢的缺点 ,通过对免疫抗体定义的改进 ,本文提出了一种基于矢量距的改进免疫算法并证明了它的全局收敛性。多峰函数优化问题的测试结果揭示基于矢量距的免疫算法在全局收敛性方面要优于遗传算法 ;在收敛速度方面要快于基于信息熵的免疫算法。

关键词：免疫算法熵矢量距收敛性

Local and Global Synchronization Criteria for a Generalized Complex Dynamical Network Model

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CRYSTALLIZATION KINETICS OF HOMOGENEOUS AND HETEROGENEOUS LLDPE

2011 Chinese Control and Decision Conference（CCDC）

作者： Ming Gao is with college of Information and Electrical Engineering,Shandong university of Science and technology,Qingdao 266510,china Li Sheng is with college of Information and Control Engineering,china university of Petroleum (East china),Dongying 257061,china

This paper investigates the local and global synchronization of a generalized complex dynamical network model with constant and delayed *** uncoupled dynamical behavior at each node is general,and can be chaotic or *** constructing a new class of Lyapunov functionals combined with free-weighting matrices,a less conservative criterion ensuring delay-dependent synchronization is derived in terms of linear matrix inequalities（LMIs）.Furthermore,the sufficient condition for the global synchronization of the generalized network is obtained.A prototype composed of the chaotic Duffing oscillators is discussed to illustrate the theoretical results and the effectiveness of the proposed synchronization scheme.

关键词： Complex Dynamical Networks Synchronization Neural Networks Linear Matrix Inequalities

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Chinese Journal of Polymer Science 2002年第4期20卷 339-345页

作者： Hong-xiang Teng Wen-hong Tang Yi Shi Xi-gao Jin State Key Laboratory of Polymer physics and Chemistry Center for Molecular Science, Institute of Chemistry Chinese Academy of Sciences Beijing 100080 china Department of Chemistry Jilin university Changchun 130023, china Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences State Key Laboratory of Polymer Physics and Chemistry 北京 100080 Department of Chemistry Jilin University Changchun 130023

Based on thermal analysis, the isothermal and nonisothemal crystallization kinetics of Ziegler-Natta catalyzed linear low density polyethylene (Z-N LLDPE) and metallocene catalyzed LLDPE (m-LLDPE) were studied. Treating the results with the Avrami equation and the Ozawa equation, the crystallization constant Igk and the Avrami exponent n were obtained. Some other crystallization parameters were also discussed. According to the different characteristics of the chain structures of Z-N LLDPE and metallocene LLDPE, their crystallization behaviors were analyzed. It is indicated that the homogeneity and heterogeneity of the two polymers act in different way during the crystallization process of polymers, including the nucleation and the growth of crystals under various conditions.

关键词： crystallization kinetics homogeneity heterogeneity LLDPE

Genetic types and distribution of shallow-buried natural gases

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Petroleum Science 2010年第3期7卷 347-354页

作者： Gao Yang Jin Qiang Zhu Guangyou college of Geo-resources and Information China University of Petroleum Dongying Shandong 257061 China Petroleum Exploration and Development Institute PetroChina Beijing 100083 China

Great volumes of shallow-buried （〈2,000 m） natural gases which are mainly composed of biogases and low-mature gases have been found in the Mesozoic-Cenozoic sedimentary basins in china. Many shallow gas reservoirs in china are characterized by coexistence of biogas and low-mature gas, so identifying the genetic types of shallow gases is important for exploration and development in sedimentary basins. In this paper, we study the gas geochemistry characteristics and distribution in different basins, and classify the shallow gas into two genetic types, biogas and low-mature gas. The biogases are subdivided further into two subtypes by their sources, the source rock-derived biogas and hydrocarbon-derived biogas. Based on the burial history of the source rocks, the source rock-derived biogases are divided into primary and secondary biogas. The former is generated from the source rocks in the primary burial stage, and the latter is from uplifted source rocks or those in a secondary burial stage. In addition, the identifying parameters of each type of shallow gas are given. Based on the analysis above, the distributions of each type of shallow gas are studied. The primary biogases generated from source rocks are mostly distributed in Quaternary basins or modem deltas. Most of them migrate in watersoluble or diffused mode, and their migration distance is short. Reservoir and caprock assemblages play an important role in primary biogas accumulation. The secondary biogases are distributed in a basin with secondary burial history. The oil-degraded biogases are distributed near heavy oil pools. The low-mature gases are widely distributed in shallow-buried reservoirs in the Meso-Cenozoic basins.

关键词： Primary biogas secondary biogas oil-degraded biogas low-mature gas genetic type gas identification gas accumulation distribution

Mild Hydrothermal Synthesis, Characterization and Properties of Na_5Ce(PO_4)_3, Na_3Yb_2(PO_4)_3·H_2O and Na_(5-2x)Yb_2xCe_(1-x)(PO_4)_3·yH_2O

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Chemical Research in Chinese Universities 2000年第4期16卷 287-300页

作者： XU Yao-hua, WANG Dan, FENG Shou-hua, PANG Wen-qin and YUE Yong (Key Laboratory of Inorganic Synthesis & Preparative Chemistry, Jilin university, Changchun 130023, P. R. china Wuhan Institute of physics, Academia Sinica, Wuhan 430071, P. R. china) 吉林大学无机合成与制备化学开放实验室吉林长春 130023 中科院武汉物理与数学所湖北武汉 430071

Novel phosphates, Na5-2x Yb2xCe1-x (PO4)3·yH2O(x=0-1, y=0-1), were synthesized under mild hydrothermal conditions at 240℃ with Ce(SO4)2·H2O, Ce(SO4)2·2(NH4)2SO4· 4H2O, CeO2, Yb2O3, 85 % H3PO4 and NaOH as the starting materials. The products were sensitively influenced by the pH value of the systems and reaction temperature. Under an acidic condition, CePO4 was the product at 240℃, in which Ce(Ⅳ ) species was reduced to Ce(Ⅲ) species. Under a weak basic condition, Na2Ce(PO4)2·0. 79H2O was produced. Under a medium basic condition, the expected compound Na5Ce(PO4)3 was the product. Under a basic condition, CeO2 was the final product, amorphous phase was also produced in some cases. The structure of the compounds were investigated by X-ray diffraction, SEM, IR, Raman, 31P MAS NMR and XPS spectroscopies. To determine the valence of Ce in the compound, EPR and DRS of the compound were also recorded. The thermal properties of the compounds were determined with DTA-TG analysis. Na5Ce(PO4)3 was decomposed into Na3Ce(PO4)2, Na4P2O7 and O, at 694℃, in which Ce(Ⅳ) was reduced to Ce(Ⅲ) species. Na3Yb2(PO4)3·H2O lost water and was transferred into a new phase at a high temperature 682℃. The thermal stability of Na5-2xYb2xCe1-x (PO4)3· yH2O could be improved by increasing x value. When x=0. 54, the compound was stable even at the temperature ca. 1 000℃.The ionic conductivities of the compounds were increased when the amount of Yb in the compound was increased and when x=0. 33, it reached the highest value (σ300℃= 3. 96 ×10-6 S·cm-1).

关键词： Cerium Ionic conduction Mild hydrothermal synthesis Rare earth phosphate Ytterbium

Microstructure and properties of the sintered diamond reinforced by diamond-MWCNTs composite fibers

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金刚石与磨料磨具工程 2008年第S1期28卷 56-61页

作者： Deng Fuming~(1,2) Lu Xuejun~(1,3) Liu Ruiping~1 Xu Guojun~3 Chen Quwu~1 Li Wenzhu~2 (1.Department of Materials Science and Engineering,china university of Mining and technology,Beijing Campus,Beijing,100083,china) (2.Department of physics,Zhejiang university,Hangzhou,310027,china) (3.Beijing Institute of Electro-machining,Beijing,100083,china)

A new type of sintered diamond reinforced by diamond MWCNTs composite fibers which were randomly orientated and even distributed in the diamond matrix was synthesized by using 3wt%mullti-walled carbon nanotubes（MWCNTs） as starting additive under high pressure of 5.8 GPa at temperature of 1500℃for 1 min.A special polycrystalline diamond structure of direct bonding of both diamond to diamond and diamond to diamond-MWCNTs composite fiber was *** testing results show that it possesses not only high hardness（49～52 GPa） and Young’s modulus（878 GPa） but also high bending strength（1320～1540 GPa） and fracture toughness(9.0～9.2 MPa·m1/2) as it was theoretically *** high performances of the composite were contributed by the fiber strengthening effect and the special structure which can offer more extensive diamond to diamond bonding.

关键词： mullti-walled carbon nanotubes(MWCNTs) nano-polycrystalline diamond fiber high pressure high temperature(HP-HT) properties

Experiment Researches on Active Fibre Probe for Scanning Near-field Optical Microscopy

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Chinese Journal of Lasers 1997年第6期 34-38页

作者： ZHANG Guoping MING Hai CHEN XiaogangYANG Bao XIE Jianping(Department of physics, university of Science & technology of china,Hefei 230026, china)

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关键词： nearfield optics SNOM active fiber probe amplified spontaneous emission

Dynamics in a Delayed Differential-algebraic Model with Stage Structure and Diffusion

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Comparative Study of Apoptosis-related Gene Loci in Human,Mouse and Rat Genomes

2011 Chinese Control and Decision Conference（CCDC）

作者： Yi Zhang is with the college of Science,Shenyang university of technology,Shenyang,P R china.Zhiwu Zhao is with the college of Information Engineering,Dalian university,Dalian,P R china.

A delayed differential-algebraic bio-economic model is proposed,which is utilized to investigate interaction and coexistence mechanism of biological population in the harvested ecosystem due to the variation of population spatial diffusion and gestation *** stability of the proposed model with gestation delay and diffusion is studied,which reveals that the interior equilibrium loses its stability at some critical values of gestation delay and corresponding cycle *** is also shown that population spatial diffusion and harvesting have a stabilizing effect on population ***,numerical simulations are carried out to show consistency with theoretical analysis obtained in this paper.

关键词： prey-predator harvest effort spatial diffusion bifurcation

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Acta Biochimica et Biophysica Sinica 2005年第5期37卷 341-348页

作者： Yan-Bin YIN Yong ZHANG Peng YU Jing-Chu LUO Ying JIANG Song-Gang LI Center of Bioinformatics, National Laboratory. of Genetic Engineering and Protein Engineering, college of Life Sciences Peking university,Beijing 100871, china Center of Bioinformatics National Laboratory of Genetic Engineering and Protein Engineering College of Life Sciences Peking UniversityBeijing 100871 China

Many genes are involved in mammalian cell apoptosis *** apoptosis genes oftencontain characteristic functional domains,and can be classified into at least 15 functional groups,accordingto previous *** an integrated bioinformatics platform for motif or domain search from threepublic mammalian proteomes(International Protein Index database for human,mouse,and rat),we system-atically cataloged all of the proteins involved in mammalian apoptosis *** localizing those proteinsonto the genomes,we obtained a gene locus centric apoptosis gene catalog for human,mouse and *** phylogenetic analysis showed that most of the apoptosis related gene loci are conserved amongthese three ***,about one-third of apoptosis gene loci form gene clusters on mammalchromosomes,and exist in the three species,which indicated that mammalian apoptosis gene orders arealso *** addition,some tandem duplicated gene loci were revealed by comparing gene loci clustersin the three *** data produced in this work were stored in a relational database and may be viewedat http://***/database/***.

关键词： apoptosis gene cluster comparative genomics bioinformatics