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Stochastic resonance in surface catalytic oxidation of carbon monoxide induced by colored noise

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Science china Chemistry 2004年第2期47卷 106-112页

The dynamical behavior of surface catalytic oxidation reaction of Pt(1.0)/CO+O2.modulated by colored noise, under the condition of specific temperature, has been investigated when the partial pressure of CO gas is near the supercritical Hopf bifurcation point. By computer simulation the oscillation and stochastic resonance induced by colored noise are observed. The influences of the intensity and correlation time of colored noise on stochastic resonance are discussed. The range of sensitivity of the system to the environmental fluctuation is analyzed.

关键词： colored noise, stochastic resonance, surface catalytic reaction of Pt(1.0)/CO+O2. supercritical Hopf bifurcation, signal-to-noise ratio (SNR).

The realization and structure of complete Lie algebras whose nilpotent radicals are Heisenberg algebras

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Chinese Science Bulletin 1998年第5期43卷 383-385页

作者： JIANG Cuibo 1.and MENG Daoji 2.1.Department of Mathematics,{1. teachers University,{2., china 2.Department of Mathematics,Nankai University,Tianjin 300071. china. Department of Mathematics Yantai Teachers University Yantai China Department of Mathematics Nankai University Tianjin China

The realization and structure of complete Lie algebras whose nilpotent radicals are Heisenberg algebras over the complex field C are given.

关键词： complete Lie algebra Heisenberg algebra nilpotent radical.

Modulation on the collective response behavior by the system size in two-dimensional coupled cell systems

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Science china({1.,Mechanics & Astronomy) 2006年第3期49卷 304-312页

作者： ZHANG Jiqian1. SHEN Chuansheng1.2.& CUI Zhifeng1.1. College of {1. and Electronic Information, Anhui Normal University, Wuhu 2.1.00, china 2. Department of Educational Technology, Anqing {2. College, Anqing 2.601., china College of physics Electronic Information Anhui Normal University Wuhu 241000 China Department of Educational Technology Anqing Teachers College Anqing 246011 China

By the intracellular calcium ionic minimal model proposed by Berridge, we investigated the collective response of two-dimensional (N×N) coupled cell systems to the external stimulation using numerical simulation methods. With a coupled intensity fixed and an appropriate coupled cell number chosen, the kinetic system size resonance was discovered. At the same time, it was found that the system size responding to the external stimulation for different coupled intensities transferred too, especially when the coupled intensity increased, the range of the corresponding system size extended. These phe- nomena illustrate that the coupled cell number and the coupled intensity can play con- structive roles in noisy coupled systems, by which the biology system would probably improve its capability to respond to the external stimulation.

关键词： cell coupling,collective response,system size resonance

Exponential attractors of the nonlinear wave equations

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Chinese Science Bulletin 1998年第16期43卷 1331-1335页

作者： DAI Zhengde 1.and MA Dacai 2.1. Department of Mathematics, Yunnan University, Kunming 650031.{1. 2. Department of Mathematics, Shangrao teachers College, Shangrao 334000,{1. Department of Mathematics Yunnan University Kunming China Department of Mathematics Shangrao Teachers College Shangrao China

The (E, E)-type exponential attractors for the nonlinear wave equation were obtained by using the decomposition of operators and finite covering *** results solves the open problem of Eden et al.

关键词： nonlinearity wave equations exponential attractors.

Potential control of horseradish peroxidase immobilization on gold electrode

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中国科学：化学英文版 2004年第2期47卷 134-141页

作者： GE Cunwang1.2. YU Wei1. LI Changan1. WANG Nanping2.& GU Ning1.1. Key Laboratory of Molecular and Biomolecular Electronics (Southeast University), Ministry of Education, Research Center for Nano-scale Science and Technology, Southeast University, Nanjing 2.0096, china 2. Department of Chemistry, Nantong teachers College, Nantong 2.6007, china 1. Key Laboratory of Molecular and Biomolecular Electronics (Southeast University) Ministry of Education Research Center for Nano-scale Science and Technology Southeast University 210096 Nanjing China 2. Department of Chemistry Nantong Teachers College 226007 Nantong China

A new approach based on potential control was firstly used for the immobilization of horseradish peroxidase (HRP) as the model protein. The self-assembly monolayer (SAM) was prepared with 2.aminoethanethiol (AET) on the gold electrode. The charge on HRP was adjusted by means of the acidity of the phosphate buffer solution (PBS) for dissolving the HRP. The in-fluence of electric potential on HRP immobilization was investigated by means of colorimetric immunoassay of enzyme-substrate interaction (CIESI) using an automatic plate reader. The HRP modified electrodes were characterized with X-ray photoelectron spectroscopy (XPS) as well as atomic force microscope (AFM) on template-stripped gold surface. The potential for maximum immobilization of HRP was near the zero charge potential. The result indicates that controlled potential can affect the course of HRP immobilization without the loss of enzymic activity. It is of great significance for the control of biomolecular self-assembly and the intrinsic electric device.

关键词： electric potential control, horseradish peroxidase, immobilization, gold electrode, self-assembly.

Genre Analysis on the Abstracts of Graduation Papers Written by Pre-service teachers of English

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海外英语 2012年第3X期 93-95,101页

作者： ZHOU Chao-ying 1., CHEN Jun 2.(1. Foreign Language Department, Hunan First Normal University, Changsha 41.2.5, china 2. Foreign Languages Department, Qiannan Normal University for Nationalities, Duyun 558000, china) Foreign Language Department Hunan First Normal University Changsha 410205 China Foreign Languages Department Qiannan Normal Universityfor Nationalities Duyun 558000 China

As a particular genre,Abstract is a growing field of study in linguistics. Move analysis is one aspect that has conducted to describe RA abstract. This article analyzed the particular genre with the purpose of helping them work out good abstracts for academic writing to improve their ability of doing research. One hundred abstracts were selected randomly from all the 450 graduation papers written by Eng lish-major pre-service teachers in {1.1. in Hunan First Normal University in china. These informative abstracts were analyzed with the framework of Hyland's {1.00 Model. The results revealed that these English-major pre-service teachers haven't done well in the abstract writing for their graduation paper, most of whom have no good understanding about the move model and move sequence, which impli cates that explicit introduction of terms of genre, move and move sequence etc., and training on how to write good abstracts in future study are really needed.

关键词： move analysis pre-service teachers abstracts

Cycladophora davisiana(Radiolarian)in the Bering Sea during the late Quaternary:A stratigraphic tool and proxy of the glacial Subarctic Pacific Intermediate Water

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Science china Earth Sciences 2005年第10期48卷 1698-1707页

作者： WANG Rujian1.& CHEN Ronghua2.1. State Key Laboratory of Marine Geology, Tongji University, Shanghai 2.0092. china 2. The Key Laboratory of Submarine Geoscience, State Oceanic Administration, Hangzhou 31.01.0} china State Key Laboratory of Marine Geology Tongji University Shanghai china The Key Laboratory of Submarine Geoscience State Oceanic Administration Hangzhou china

Cycladophora davisiana (Radiolarian) contents are counted in two cores of the Ber-ing Sea and correlated well with the oxygen isotopic records of ice in the deep core obtained by the Greenland Ice Sheet Project II (GISP 2. and deep-sea sediments (SPECMAP) of the world oceans. Millennial scale climatic events, for example, Younge Dryas and B?lling/Aller?d events, Heinrich1.and Dansgaard-Oeschger1.vents, recorded by C. davisiana percents are distin-guished from Core B4-2. C. davisiana events b, c1. c2. d, e1.and e2. respectively, corresponding to oxygen isotopic 2.0, 3.1. 3.3, 4.0, 5.1.and 5.3, are identified from Core B2.9. High resolution re-cords of C. davisian are tuned to the oxygen isotopic records in GISP 2.and SPECMAP and the depth-age frameworks are established in the two cores, supplying a stratigraphic base for future paleoceanographic and paleoclimatic studies. High C. davisiana during the glacial periods in the two cores indicate that they can serve as a proxy of the glacial Subarctic Pacific Intermediate Water, which verifies the glacial Subarctic Pacific Intermediate Water brought from the Bering Sea.

关键词： Cycladophora davisiana, stratigraphic tool, YD and B/A events, Heinrich 1 and D/O1 events, proxy of glacial Subarctic Pacific Intermediate Water, late Quaternary, Bering Sea.

Variation of karst spring discharge in the recent five decades as an indicator of global climate change: A case study at Shanxi, northern china

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Science china Earth Sciences 2005年第11期48卷 2001-2010页

作者： GUO Qinghai1. WANG Yanxin1. MA Teng1.& LI Luxiu2.1. School of Environmental Studies,{1. University of Geosciences, Wuhan 430074,{1. 2. Office of Water Resource Management of Shanxi Province, Taiyuan 030001.{1. 1. School of Environmental Studies China University of Geosciences 430074 Wuhan China 2. Office of Water Resource Management of Shanxi Province 030001 Taiyuan China

Karst in Shanxi Province is representative of that in northern china, and karst water systems discharge in the form of springs that are among the most important sources for local water supply. Since the 1.50s, attenuation has been the major trend of discharge variation of most karst springs at Shanxi. Based on the case study of 7 karst springs including Niangziguan, Xin’an, Guozhuang, Shentou, Jinci, Lancun, and Hongshan springs, the discharge variation process of karst springs was divided into natural fluctuation phase and anthropogenic impact phase. Discharge attenuation of the 7 karst springs was controlled mainly by climate and human activities, with their contributions being respectively about 60% and 40%. According to the dif-ference of the effect of climate and human activities for each spring, attenuation modes of spring discharge fall into three types: natural process dominated attenuation type, exploitation induced process dominated attenuation type, and mixed attenuation type. The total restored discharge variation of 7 karst springs matched well with the global air temperature change in 1.56―{1.00, clearly indicating the trend of global warming and aridity in the last several decades, and the analysis of discharge variation processes of karst springs can be used as a new tool for global change studies.

关键词： karst, Shanxi, spring discharge, attenuation, climate, human activity, global change

Refractive index changes induced by sheet beams with various intensity distributions in LiNbO_(3):Fe crystal

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Science china({1.,Mechanics & Astronomy) 2005年第4期48卷 399-412页

作者： ZHANG Peng1. ZHAO Jianlin1. XU Honglai1. SUN Yidong2. YANG Dexing1.& WANG Meirong1.1. Institute of Optical Information Science and Technology, School of Science, Northwestern Polytechnical University, Xi’an 71.072. china 2. School of Science, Xi’an Jiaotong University, Xi’an 71.049, china 1. Institute of Optical Information Science and Technology School of Science Northwestern Polytechnical University 710072 Xi’an China 2. School of Science Xi’an Jiaotong University 710049 Xi’an China

According to the Kukhtarev equations and a simplified model based on the photovoltaic charge carriers transport mechanism, the distributions of the index changes (DICs) in LiNbO3:Fe crystals induced by sheet beams with various intensity profiles are theoretically analyzed. The numerically simulated results coincide with the analytic expressions deduced from the simplified model. The DICs in a LiNbO3:Fe crystal induced by sheet beams with rectangular, Gaussian and square law profiles are measured by using the interferometric method. By employing the analytic expressions, the experimental data points are well fitted. By utilizing the angular spectrum theory and the ray equation, the uniformities of the intensity profiles of the writing beams along the propagation directions and the influences of the self-defocusing effect of the crystal are numerically simulated, respectively. The results show that the experimental results are reliable. The numerically simulated method and the analytic expressions can be both employed to predict the DICs induced by sheet beams with various light intensity profiles. Furthermore, utilizing writing beams with proper intensity profiles, any desired index distributions could be obtained.

关键词： LiNbO3:Fe crystal, light intensity profile, distribution of refractive index changes, sheet beam.