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Acta Oceanologica Sinica 2000年第2期19卷 37-44页

作者： Chen Feizhou1 Huang Yipu2.Chen Min2.(1. college of Fishery Science, Shanghai Fisheries university, Shanghai 2.0090, China 2. {2. of Oceanography, Xiamen university, Xiamen 361005, China) college of Fishery Science Shanghai Fisheries University Shanghai 200090 China

The spatial and temporal distributions of new production vary largely in different sea areas. To understand the level of new production in the sea area studied better, an estimate of new production must be obtained in large spatial and temporal scales. The ~2.4Th/ ~2.8U disequilibrium is an effective method for the study of new production. Two sampling strategies, vertically integrated sampling ap proach based on trapezoidal integration principle and discrete layer sampling approach, were compared in the studies of the xiamen Bay and the northern South China Sea. The scavenging fluxes and removal fluxes of ~2.4Th and the residence times for dissolved and particulate ~2.4Th were calculated. The coinci dent results from two Sampling approach suggest that vertically integrated sampling approach is not only effective and reliable, but also significantly reduces the number and volume of samples. It allows us to study new production by ba ^(2.4)Th - ^(2.8)U disequilibria in large spatial scale.

关键词： New production vertically integrated Sampling approach, ^(2.4)Th - ^(2.8)U disequilibria Xia men Bay northern South China Sea

Research on the method for retrieving soil moisture using thermal inertia model

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Science China Earth Sciences 2006年第5期49卷 539-545页

作者： LIU Zhenhua1 & ZHAO Yingshi2.1. Information college, South China Agricultural university, Guangzhou 510642. China 2. Graduate university of Chinese Academy of Sciences, Beijing 100049, China 1. Information college South China Agricultural University Guangzhou 510642 China 2. Graduate university of Chinese Academy of Sciences Beijing 100049 China

In order to improve accuracy of soil moisture inversion using remote sensing, a new thermal inertia model is proposed in this paper. The improved model needs only surface maximum temperature as the temperature parameter input instead of input of the surface temperature difference, as well as the surface sensible and latent fluxes are introduced into boundary conditions of thermal conductivity equation. Furthermore, surface soil conductive heat transfer equation of two-layer model is used to solve the soil thermal inertia so that the remote sensing thermal inertia method can be ap- plied to regions with better-covered vegetation, but usually only for the bare areas or worse vegetation covered areas. The model has been tested at several locations in the area of west Inner Mongolia. Comparing the simulation of the new model with the measurements obtained by apparent thermal inertia and by field test, the result shows that the inertia thermal model can be used to estimate soil moisture in more reasonable accuracy.

关键词： thermal model, thermal conductivity equation, soil initial, sensible flux, latent flux, two-layer model.

Transitional function of DG to CA3 in the hippocampus

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Progress in Natural Science:Materials International 2007年第12期17卷 1436-1444页

作者： Yan Chuankui1 and Liu Shenquan2.1. department of Mathematics, Hangzhou Normal university, Hangzhou 310036, China 2. department of Applied Mathematics, School of Mathematical Sciences, South China university of Technology, Guangzhou 510640, China) department of Mathematics Hangzhou Normal University Hangzhou 310036 China department of Applied Mathematics School of Mathematical Sciences South China University of Technology Guangzhou 510640 China

Using single cell channel model, the transmission features of CA3-DG network in the hippocampus are investigated. The influence of the stimulation on discharge pattern of pyramidal neurons is analyzed, which shows that it starts with period spiking discharges, followed by period-doubling bifurcation to chaos, and period 3 discharge evolving into chaos, and ultimately a period of bursting discharges. By the synaptic model, the CA3-DG network model is constructed, which analyzes the summation of postsynaptic currents in the network, the influence of postsynaptic current on discharge rhythm as well as the mechanism of bursting discharges. The strong capacity of spatiotemporal encoding in the network indicates the features of CA3 network during the information transmission process in the hippocampus. The modeling result with time delay of the synaptic transmission is in accordance with the experimental phenomena of action potential in the hippocampus.

关键词： hippocampus CA3-DG period-doubling bifurcation chaos.

The mechanism of breakdown in laminar-turbulent transition of a supersonic boundary layer on a flat plate-temporal mode

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Science China(Physics,Mechanics & Astronomy) 2005年第5期48卷 614-625页

作者： HUANG Zhangfeng 1, CAO Wei 1,2.& ZHOU Heng 1,2.1. department of Mechanics, Tianjin university, Tianjin 300072. China 2. Liu-Hui Center of Applied Mathematics, Nankai university and Tianjin university, Tianjin 300072. China 1. department of Mechanics Tianjin University 300072 Tianjin China 2. Liu-Hui Center of Applied Mathematics Nankai University and Tianjin University 300072 Tianjin China

Temporal mode direction numerical simulation has been done for the transition of a supersonic boundary layer on a flat plate with Mach number 4.5. Analysis of the result showed that during the breakdown process in laminar-turbulent transition, the mechanism causing the mean flow profile to evolve swiftly from laminar to turbulent was that the modification of mean flow profile by the disturbances,when they became larger,led to a remarkable change of its stability characteristics. Though the most unstable T-S wave was of second mode for laminar flow, the first mode waves played the key role in the breakdown process in laminar-turbulent transition.

关键词： supersonic boundary layer, transition, breakdown.

DNA fragmentation in apoptosis

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Cell Research 2000年第3期10卷 205-211页

作者： ZHANG JiaN HUA, MING XU (department of Cell Biology, Neurobiology and Anatomy, university of Cincinnati {2. of medicine, Cincinnati, Ohio 452.7052., USA) departmentofCellBiology NeurobiologyandAnatomyUniversityofCincinnatiCollegeofMedicineOhio45267-0521USA.

Cleavage of chromosomal DNA into oligonucleosomal size fragments is an integral part of apoptosis. Elegant biochemical work identified the DNA fragmentation factor (DFF) as a major apoptotic endonuclease for DNA fragmentation in vitro. Genetic studies in mice support the importance of DFF in DNA fragmentation and possibly in apoptosis in vivo. Recent work also suggests the existence of additional endonucleases for DNA degradation. Understanding the roles of individual endonucleases in apoptosis, and how they might coordinate to degrade DNA in different tissues during normal development and homeostasis, as well as in various diseased states, will be a major research focus in the near future.

关键词： DNA fragmentation DFF endonucleases apop tosts.

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 01002., 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.

Minimal systems of generators for central division algebra and semi-simple algebra

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Chinese Science Bulletin 1998年第21期43卷 1777-1780页

作者： QIU Qizhang 1 and SUN Ling 2.1. department of Mathematics, Wuhan university, Wuhan 430072. China 2. department of Information science, Wuhan university, Wuhan 430072. China. department of Mathematics Wuhan University Wuhan China department of Information science Wuhan University Wuhan China

Suppose that F is a field of characteristic zero and (ⅰ) D is a finite-dimensional central division algabra over F; (ⅱ) A is a finite-dimensional semi-simple algabra over F. It is proved that as F-algebras, D and A ... 详细信息

关键词： central division algebra semi-simple algebra generator minimal system of generators.

Lipschitz continuity of best approximations and Chebyshev centers

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Chinese Science Bulletin 1998年第3期43卷 185-188页

作者： LI Chong 1 and WANG Xinghua 2.1. Center for Mathematical Sciences, Zhejiang university, Hangzhou 31002., China 2. department of Mathematics, Hangzhou university, Hangzhou 31002., China Center for Mathematical Sciences Zhejiang University Hangzhou China department of Mathematics Hangzhou University Hangzhou China

The Lipschitz continuity results are given for best approximations and Chebyshev centers. Consequently, the open problem presented by Septycki and Vleck is solved completely.

关键词： best approximation Chebyshev center uniform convexity.

Crank conditions and rotatability of 3-RRR planar parallel mechanisms

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Science China(Technological Sciences) 2009年第12期52卷 3601-3612页

作者： LI RuiQin 1 &DAI Jian S 2.1 college of Mechanical Engineering and Automation,North university of China,Taiyuan 030051,China 2.{2. of Mechanical Engineering,King’s college London,university of London,WC2. 2.S,UK college of Mechanical Engineering and Automation North University of China Taiyuan 030051 China department of Mechanical Engineering King’s College London University of London WC2R 2LS London UK

This paper investigates the rotatability of planar parallel mechanisms by revealing the crank conditions that relate to link *** paper extends the theorem of assemblability and the rotatability criterion and applies these criteria to parallel mechanisms in investigating the crank conditions of a parallel mechanism,leading to classification of three types of crank existing conditions including three-crank’s,six-crank’s and nine-crank’s of 3-RRR planar parallel *** results are summarized as constraint conditions in relation with link parameters with a concluding table and case studies.

关键词： crank rotatability planar parallel mechanism

Sensitive Determination of DNA by RLS Enhancement of Metal Ions

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Wuhan university Journal of Natural Sciences 2004年第2期9卷 234-238页

作者： Huang Jian-ping 1,2. Chen Fang 1, Ai Xin-ping 1, He Zhi-ke 1 1. college of Chemistry and Molecular Sciences, Wuhan university, Wuhan 430072. Hubei, China 2. {2. of Environmental Engineering, Hubei Agricultural college, Jingzhou 43402., Hubei, China Wuhan university College of Chemistry and Molecular Sciences Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) Hubei Agricultural college Department of Environmental Engineering Jingzhou Hubei China (GRID:grid.49470.3e) Wuhan university College of Chemistry and Molecular Sciences Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

The interactions between metal ions and DNA have been studied by the resonance light scattering (RLS) spectra. In the acidic condition, the RLS signals of metal ions, especially the transition metal ions in group IB and IIB, were increased by DNA. And it is found that the enhancement of RLS signals is linear to the concentration of DNA, so the RLS method for DNA determination was proposed in the presence of Cu2.. On the optimum conditions, the linear range and the detect limit of ctDNA is 4×10?8–4×10?6 g· mL?1 and 1. 13×10?8 g·mL?1, respectively. The proposed method is successfully applied to determine the extracted plasmid DNA ofBacillus subtilis DB104. Key words resonance light scattering - DNA - metal ions CLC number O 657.3 Foundation item: Supported by National Natural Science Foundation of China (2.2.502.) and the National Key Basic Research and Development Program (973 Program 2.02.B2.1800).Biography: Huang Jian-ping(1964-), male, Associate professor, research direction: bioanalysis.

关键词： resonance light scattering DNA metal ions