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Challenges in the theoretical investigations of lipid membrane configurations

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Chinese physics B 2013年第2期22卷 36-44页

作者：涂展春 department of physics Beijing Normal University Kavli Institute for Theoretical physics China Chinese Academy of Sciences

We report some key results in the theoretical investigations of configurations of lipid membranes and present several challenges in this field,which involve（i）the exact solutions to the shape equation of lipid vesicles,（ii）the exact solutions to the governing equations of open lipid membranes,（iii）the neck condition of two-phase vesicles in the budding state,（iv） the nonlocal theory of membrane elasticity,and（v）the relationship between the symmetry and the magnitude of the free energy.

关键词： configuration lipid membrane

C^(18)O Observations of the Dark Molecular Cloud L134 and Gas Depletion onto Dust

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Chinese Journal of Astronomy and Astrophysics 2005年第2期5卷 144-150页

作者： Xin-Jie Mao and Xiao-Xia Sun department of Astronomy, beijing normal university,{2. maoxj@*** department of Astronomy Beijing Normal University Beijing 100875

We map the dark molecular cloud core of L134 in the C^(18)O (J = 1 - 0)emission line using the PMO 13.7m telescope, and present a contour map of integrated intensity ofC^(18)O (J = 1 - 0) emission. The C^(18)O cloud is inside the distribution of extinction A_B, thevisual extinction of blue light, as well as inside the ^(13)CO cloud in the L134 region. Thedepletion factors in this C^(18)O cloud are generally greater than unity, which means there is gasdepletion onto dust. Since only a minimum A_B - 9.7 mag is available, and our observations measureboth undepleted and depleted regions along the line of sight, the depletion factors could verylikely be larger in the central core than the calculated value. So we conclude that depletion doesoccur in the bulk of the C^(18)O cloud through a comparison between the C^(18)O and blue extinctionmaps in the L134 region. There is no direct evidence as yet for star formation in L134, and so coreson the verge of collapse will not be visible in CO and other gas molecules.

关键词： ISM: clouds ISM: individual (L134) ISM: molecules ISM: extinction

Effects of nitrogen ion implantation on Ca^(2.) concentration and membrane potential of pollen cell

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Chinese Science Bulletin 2001年第20期46卷 1691-1693页

作者： HUANG Zhonglian, JING Yanping, ZHU Guoli, LU Ting, ZHOU Hongyu & REN Haiyun1. Key Laboratory of Cell Proliferation and Regulation Biology of the Ministry of Education, beijing normal university, beijing 100875, China 2. Key Laboratory of Plant Physiology and Biochemistry of the Ministry of Agriculture, China Agriculture {2., beijing 100094, China 3. Institution of Low Energy Nuclear physics, beijing normal university, beijing 100875, China Key Laboratory of Cell Proliferation Regulation Biology of Min. of Educ. Beijing Normal University Beijing 100875 China

The effects of low energy nitrogen ion implantation on Ca2. concentration and membrane potential of illy (Mum davidii Duch) pollen cell have been studied. The results showed that the Ca2. concentration was increased when pollen grain was implanted by nitrogen ion with energy 100 keV and dose 1013 ions/cm2. However, the increase of Ca2. concentration was partly inhibited by the addition of Ca2. channel inhibitor depending on dose. And nitrogen ion implantation caused depolarization of pollen cell membrane potential. In other words, membrane potential was increased, but the effect decreased by adding Ca2. channel inhibitor. However, it was still significantly higher than the membrane potential of control cells. It was indicated that the depolarization of cell membrane potential opened the calcium channel on the membrane that caused the increasing of intracel-lular calcium concentration. This might be an earlier step of the effect of low energy nitrogen ion implantation on pollen germination.

关键词： nitrogen ion implantation lily pollen calcium concentration membrane potential.

The Goldbach 3-primes property for polynomial rings over certain infinite fields

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Chinese Science Bulletin 1998年第15期43卷 1256-1260页

作者： WANG Shiqiang department of Mathematics, beijing normal university,{2., China department of Mathematics Beijing Normal University Beijing China

On the basis of Effinger and Hayes’ theorem about the Goldbach 3_primes property of polynomial rings F over finite fields F , by model_theoretic method it is proved that for each characteristic k (including 0), there... 详细信息

关键词： model theory polynomial 3 primes property.

The Electrochemical Behavior of Bleomycin at A Co/GC Ion Implantation Modified Electrode

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Chinese Chemical Letters 1999年第10期10卷 855-856页

作者： Jing Bo HU Qi Long LI (department of Chemistry, beijing normal university,{2.) beijing normal Univ Dept Chem Beijing 100875 Peoples R China

In 0.10 mol/L HOAc-NaOAc buffer solution (pH 4.59). a sensitive reduction peak of bleomycin is obtained by linear sweep voltammetry at Co/GC ion implantation modified electrode. Its electrochemical behavior has been studied. The experiments of AES and XPS show that Co is surely implanted into the surface of GCE and improved the electrocatalytic activity.

关键词： ion implantation electrochemical behavior bleomycin

A trust region algorithm for bilevel programing problems

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Chinese Science Bulletin 1998年第10期43卷 820-824页

作者： LIU Guoshan 1, HAN Jiye 2.and WANG Shouyang 3 1. department of Mathematics, beijing normal university,{2., China 2. Institute of Applied Mathematics, Chinese Academy of Sciences, beijing 100080, China 3. Institute of Systems Science, Chi department of Mathematics Beijing Normal University Beijing China Institute of Applied Mathematics Chinese Academy of Sciences Beijing China Institute of Systems Science Chinese Academy of Sciences Beijing China

A trust region algorithm is proposed for solving bilevel programming problems where the lower level programming problem is a strongly convex programming problem with linear constraints. This algorithm is based on a tr... 详细信息

关键词： bilevel programming problem trust region algorithm global convergence.

OPTIMIZATION OF ADAPTIVE DIRECT METHOD FOR APPROXIMATE SOLUTION OF INTEGRAL EQUATIONS OF SEVERAL VARIABLES

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Acta Mathematica Scientia 2004年第2期24卷 228-234页

作者：马万房艮孙 departmentofMathematics BeijingNormalUniversityBeijing100875China

This paper determines the exact error order on optimization of adaptive direct methods of approximate solution of the class of Fredholm integral equations of the second kind with kernel belonging to the anisotropic So... 详细信息

关键词： Integral equations direct methods anisotropic sobolev classes

Development and application of ergodicity model with FRCM and FLAR for hydrological process

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Science China(Technological Sciences) 2009年第2期52卷 379-386页

作者： WANG HongRui1, FENG QiLei2. LIN Xin3 & ZENG WenYi4 1 College of Water Science, Key Laboratory for Water and Sediment Sciences of the Ministry of Education, beijing normal university, beijing 100875, China 2.School of Science, {2. Institute of Education, {2. 100011, China 3 School of Mathematical Sciences, beijing normal university, beijing 100875, China 4 College of Information Science and Technology, beijing normal university, beijing 100875, China 1. College of Water Science Key Laboratory for Water and Sediment Sciences of the Ministry of Education Beijing Normal University Beijing 100875 China 2. School of Science Beijing Institute of Education Beijing 100011 China 3. School of Mathematical Sciences Beijing Normal University Beijing 100875 China 4. College of Information Science and Technology Beijing Normal University Beijing 100875 China

In this paper, a new ergodic property analysis model of hydrological process is proposed based on fuzzy-rough c-means clustering (FRCM), autocorrelogram, and fuzzy least absolute regression (FLAR). A precipitation time series (1951―2.04) from Shanghai Hydrology Station is then analyzed with the model. The results show that the precipitation time series of April, May, June, and September has er-godic property. We conclude that in the long run, the precipitation of April, May, June, and September will not keep decreasing; it will converge to its mean value in some period.

关键词： hydrological process ergodic autocorrelogram fuzzy-rough c-means clustering fuzzy least absolute regression

Nash Inequalities for General Symmetric Forms

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Acta Mathematica Sinica,English Series 1999年第3期15卷 353-370页

作者： Mufa Chen department of Mathematics, beijing normal university,{2., P. R. China department of Mathematics Beijing Normal University Beijing P. R. China

This paper deals with the Nash inequalities and the related ones for general symmetric forms which can be very much unbounded. Some sufficient conditions in terms of the isoperimetric inequalities and some necessary conditions for the inequalities are presented. The resulting conditions can be sharp qualitatively as illustrated by some examples. It turns out that for a probability measure, the Nash inequalities are much stronger than the Poincare and the logarithmic Sobolev inequalities in the present context.

关键词： Nash inequality Symmetric form Isoperimetric Inequality Jump process