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SPECTRUM CHARACTERISTICS OF MAJOR IONCONCENTRATIONS AT WUHAN SECTOIN OF THECHANGJIANG RIVER

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Chinese Geographical Science 2001年第4期11卷 29-34页

作者： XIA Xing-hui1, CHEN Jing-sheng2. CAI Xu-yi3(1. Institute of Environmental Sciences, Beijing normal university / State Key Joint Laboratory of EnvironmentalSimulation and Pollution Control, Beijing {2., P. R. china 2. department of U Institute of Environmental Sciences Beijing Normal University/ State Key Joint Laboratory of Environmental Simulation and Pollution Control Beijing P.R. China department of Urban & Environmental Science Peking University Beijing P. R. China Geography department Graduate School of University of Science and Technique of China Beijing P. R. China

ABSTRACT: Spectrum analyses of water quality time series have been carried out for five hydrometric stations including Wuhan hydrometric station of the Changjiang( Yangtze) River, etc. The fluctuations of Ca2.+, Mg2. and HCO3-concentrations in river water under different physical geography conditions have about two-year cycle which is corresponding to hydrometeorological quasi-biannual-oscillation(QBO). Na + Cl- SO2.4 have about two-year cycle in the area lightly affected by human activities while two-year cycle doesn’t exist in the area heavily affected by human activities. All the fluctuations of major ions have about three-month cycle. The river discharge fluctuation accounts for 43. 9% , 45.1%, 54.3%, 33.9%, 30.3% and 42. 7% of the variance of Ca2.+, Mg2. HC03-, Na+ Cl-, SO2.4, respectively, at Wuhan from 1962.to 1985. According to the spectrum characteristic of major ions, the duration of the time series has to be at least 13 years for trend analysis of monthly water quality data.

关键词： major ions spectrum characteristic of water quality water quality change the Changjiang River

1.55 μm Wavelength Operation of E_r^(3+) -Doped Optical Fiber Bistability

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Wuhan university Journal of Natural Sciences 1999年第4期4卷 435-438页

作者： SONG Qian 1, ZHANG Yuan cheng 2.1. College of Electronics Information, Wuhan university, Wuhan 430072. china {2., Wuhan university, Wuhan 430072. china Wuhan university College of Electronics Information Wuhan China (GRID:grid.49470.3e) (ISNI:***) Wuhan university Department of Physics Wuhan China (GRID:grid.49470.3e) (ISNI:***)

An all optical all fiber optical bistability operation has been realized in an all fiber cavity consisted with Er doped fiber and optical fiber loop mirrors. The experimental bistability threshold is consistent w... 详细信息

关键词： optical nonlinearity optical bistability Er doped fiber all fiber device

Entropy product measure for multipartite pure states

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Science china(physics,Mechanics & Astronomy) 2006年第5期49卷 606-615页

作者： CAO Wancang1,2. LIU Dan2. PAN Feng3 & LONG Guilu2.4 1. department of physics, Chifeng College, Chifeng 02.001,{2. 2. Key Laboratory for Quantum Information and Measurements, department of physics, Tsinghua university, Beijing 100084,{2. 3. department of physics, Liaoning normal university, Dalian 11602.,{2. 4. Key Laboratory for Atomic and Molecular Nano-Sciences, Tsinghua university, Beijing 100084,{2. Correspondence should be addressed to Long Guilu department of physics Chifeng College Chifeng China Key Laboratory for Quantum Information and Measurements Department of Physics Tsinghua University Beijing China department of physics Liaoning Normal University Dalian China Key Laboratory for Atomic and Molecular Nano-Sciences Tsinghua University Beijing China

An entanglement measure for multipartite pure states is formulated using the product of the von Neumann entropy of the reduced density matrices of the constituents. Based on this new measure, all possible ways of the maximal entanglement of the triqubit pure states are studied in detail and all types of the maximal entanglement have been compared with the result of ‘the average entropy’. The new measure can be used to calculate the degree of entanglement, and an improvement is given in the area near the zero entropy.

关键词： multipartite pure state von Neumann entropy entanglement measure

Different-Periodic Travelling Wave Solutions for Nonlinear Equations

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Communications in Theoretical physics 2004年第4期41卷 481-486页

作者： YE Li-Jun~1 LIN Ji~(1,2.1 department of physics,Zhejiang {2. university,Jinhua 32.004,china2.physics department,Shanghai Jiao Tong university,Shanghai 2.0030,china department of physics Zhejiang Normal University physics department Shanghai Jiao Tong University

Using Jacobi elliptic function linear superposition approach for the(1+1)-dimensional Caudrey-Dodd-Gibbon-Sawada-Kotera(CDGSK)equation and the(2.1)-dimensional Nizhnik-Novikov-Veselov(NNV)equation,many new periodic travelling wave solutions with different periods and velocities are obtained based on the knownperiodic *** procedure is crucially dependent on a sequence of cyclic identities involving Jacobi ellipticfunctions sn(ξ,m),cn(ξ,m),and dn(ξ,m).

关键词： linear superposition nonlinear equation travelling wave solution

First-principles calculations on implanted TiO_2.by 3d transition metal ions

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Science china(physics,Mechanics & Astronomy) 2009年第6期52卷 838-842页

作者： HOU XingGang1,2. HUANG MeiDong1, WU XiaoLing2.& LIU AnDong2.1 department of physics, Tianjin {2. university, Tianjin 300387, china 2.Key Laboratory of Beam Technology and Material Modification of Ministry of Education, Beijing {2. university, Beijing 100875, china department of physics Tianjin Normal University Tianjin China Key Laboratory of Beam Technology and Material Modification of Ministry of Education Beijing Normal University Beijing China

3d transition metal (V, Cr and Fe) ions are implanted into TiO2.by the method of metal ion implantation. The electronic band structures of TiO2.films doped 3d transition metal ions have been analyzed by ab initio band calculations based on a self-consistent full-potential linearized augmented plane-wave method within the first-principle formalism. Influence of implantation on TiO2.films is examined by the method of UV-visible spectrometry. The results of experiment and calculation show that the optical band gap of TiO2.films is narrowed by ion implantation. The calculation shows that the 3d state of V, Cr and Fe ions plays a significant role in red shift of UV-Vis absorbance spectrum.

关键词： 3d transition metal ions implantation TiO2 FP-LAPW electronic structure

Robustness and breakup of the spiral wave in a two-dimensional lattice network of neurons

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Science china(physics,Mechanics & Astronomy) 2010年第4期53卷 672-679页

作者： MA Jun 1,2. TANG Jun 2., ZHANG AiHua 3 & JIA Ya 2.1 department of physics, Lanzhou {2. of Technology, Lanzhou 730050, china 2.department of physics, Central china normal {2., Wuhan 430079, china 3 College of Electrical and Information Engineering, Lanzhou {2. of Technology, Lanzhou 730050, china department of physics Lanzhou University of Technology Lanzhou 730050 China

The robustness and breakup of spiral wave in a two-dimensional lattice networks of neurons are investigated. The effect of small- world type connection is often simplified with local regular connection and the long-range connection with certain probability. The network effect on the development of spiral wave can be better described by local regular connection and changeable long-range connection probability than fixed long-range connection probability because the long-range probability could be changeable in realistic biological system. The effect from the changeable probability for long-range connection is simplified by multiplicative noise. At first, a stable rotating spiral wave is developed by using appropriate initial values, parameters and no-flux boundary conditions, and then the effect of networks is investigated. Extensive numerical studies show that spiral wave keeps its alive and robust when the intensity of multiplicative noise is below a certain threshold, otherwise, the breakup of spiral wave occurs. A statistical factor of synchronization in two-dimensional array is defined to study the phase transition of spiral wave by checking the membrane potentials of all neurons corresponding to the critical parameters(the intensity of noise or forcing current)in the curve for factor of synchronization. The Hindmarsh-Rose model is investigated, the Hodgkin-Huxley neuron model in the presence of the channel noise is also studied to check the model independence of our conclusions. And it is found that breakup of spiral wave is easier to be induced by the multiplicative noise in presence of channel noise.

关键词： spiral wave factor of synchronization breakup multiplicative noise robustness

Interannual variability of Antarctic Oscillation and its influence on East Asian climate during boreal winter and spring

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Science china Earth Sciences 2006年第5期49卷 554-560页

作者： FAN Ke1,2.3 & WANG Huijun2.1. Nansen-Zhu International Research Center, Institute of Atmospheric physics, Chinese Academy of Sciences, Beijing 10002., china 2. {2. of Atmospheric Science, Yunnan university, Kunming 650091, china 3. Graduate university of the Chinese Academy of Sciences, Beijing 100049, china Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China department of Atmospheric Science Yunnan University Kunming China Graduate university of the Chinese Academy of Sciences Beijing China

The interannual variability of Antarctic Oscillation (AAO) and its influence on East Asian climate during both boreal winter and spring are addressed. The results show that the positive AAO anomaly decreases the cold activity over East Asia during both boreal winter and spring. AAO-related barotropic meridional teleconnection from Antarctic to Arctic is found through analysis of mean me- ridional circulations. This meridional teleconnection is remarkable over Eurasia during boreal winter and over the Pacific Ocean during boreal spring. The results also show that zonal mean zonal wind at high latitudes in Southern Hemisphere has well positive correlation with that of Eurasia during boreal winter and has negative correlation with Pacific North American teleconnection (PNA) during boreal spring, which again display the meridional teleconnection. Thus, local meridional teleconnection is a possible linkage for interaction of circulations at mid-high latitudes between both hemispheres.

关键词： Antarctic Oscillation, Eurasian west wind, meridional teleconnection, mean meridional circulation.

Local and non-local sources of airborne particulate pollution at Beijing——The ratio of Mg/Al as an element tracer for estimating the contributions of mineral aerosols from outside Beijing

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Science china Chemistry 2005年第3期48卷 253-264页

作者： HAN Lihui1, ZHUANG Guoshun1,2.3, SUN Yele1 & WANG Zifa3 1. The Center for Atmospheric Environmental Study, department of Chemistry, Beijing normal {2., Beijing 100875, china 2. Center for Atmospheric Chemistry Study, department of Environmental Science & Engineering, Fudan {2., Shanghai 2.0433, china 3. LAPC/NZC, Institute of Atmospheric physics, CAS, Beijing 10002., china The Center for Atmospheric Environmental Study Department of Chemistry Beijing Normal University Beijing China Center for Atmospheric Chemistry Study Department of Environmental Science & Engineering Fudan University Shanghai China Institute of Atmospheric physics CAS LAPC/NZC Beijing China

A new element tracer technique has firstly been established to estimate the contri-butions of mineral aerosols from both inside and outside Beijing. The ratio of Mg/Al in aerosol is a feasible element tracer to distinguish between the sources of inside and outside Beijing. Mineral aerosol, inorganic pollution aerosol mainly as sulfate and nitrate, and organic aerosol are the major components of airborne particulates in Beijing, of which mineral aerosol accounted for 32.―67% of total suspended particles （TSP）, 10%―70% of fine particles （PM2.5）, and as high as 74% and 90% of TSP and PM2.5, respectively, in dust storm. The sources from outside Beijing contributed 62. （38%―86%） of the total mineral aerosols in TSP, 69% （52.―90%） in PM10, and 76% （59%―93%） in PM2.5 in spring, and 69% （52.―83%）, 79% （52.―93%）, and 45% （7%―79%） in TSP, PM10, and PM2.5, respectively, in winter, while only2.% in summer and autumn. The sources from outside Beijing contributed as high as 97% during dust storm and were the dominant source of airborne particulates in Beijing. The contributions from outside Bei-jing in spring and winter are higher than those in summer, indicating clearly that it was related to the various meteorological factors.

关键词： mineral aerosol local sources non-local sources dust storm re-suspended dust element tracer technique.

TFEL of Ce^(3+) in zine sulpho-oxide

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Chinese Science Bulletin 1998年第14期43卷 1179-1183页

作者： YU Lei\+1, LOU Zhidong\+1, XU Chunxiang\+1, XU Zheng\+2.and XU Xurong\+2.1. Institute of Material physics, Tianjin Institute of Technology, Tianjin 300191, china {2., Northern Jiaotong university, Beijing 100044, china Institute of Material physics Tianjin Institute of Technology Tianjin China department of physics Northern Jiaotong University Beijing China

A new TFEL material ZnS X O 1-X : Ce 3+ is prepared. The EL brightness of ZnS X O 1-X : Ce 3+ is at least one order higher than that of ZnS: Ce 3+ at the same doping concentration of Ce 3+ . The EL emission wavelength of ZnS X O 1-X : Ce 3+ (\%X\%=0.5) ranges from 400 to 600 nm. The emission of ZnS X O 1-X : Ce 3+ may be used as the blue part of white TFEL.

关键词： thin_film electroluminescence (TFEL) filter layered optimization zine sulpho_oxide.