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Acta Mathematica Sinica,English Series 2000年第2期16卷 261-270页

作者： Shaoyi ZhangDepartment of Mathematics.beijing normal university,beijing 100875,P.R.china Department of Mathematics,Hubei normal university,Huangshi 43.002,P.R.china Department of Mathematics Beijing Normal University Beijing 100875 P. R. China Department of Mathematics Hubei Normal University Huangshi 435002 P. R. China

In this paper,for two given transition probabilities,the existence of the optimal Markovian coupling with respect to a non-negative lower semi-continuous function is *** an application of this result,the well-known Strassen’s theorem is ***,it is proved that the existence of an order-preserving Markovian coupling of two given jump processes is equivalent to their stochastical comparability.

关键词： Transition probability Markovian coupling Jump process

The study of two-color excitation upconversion of Pr(0.5)Yb(3.:ZBLAN

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Science china(Physics,Mechanics & Astronomy) 2006年第2期49卷 169-177页

作者： CHEN Xiaobo1 & SONG Zengfu2 1. Applied Optics beijing Area Major Laboratory, Analysis and testing center, beijing normal university, beijing 100875,{3. 2. Peking university, Physics school, beijing 100871,{3. Applied Optics beijing Area Major Laboratory Analysis and testing center Beijing Normal University Beijing China Physics school Peking University Beijing China

The excited state absorption upconversion of Pr(0.5)Yb(3.:ZBLAN glass material, under two-color excitation of the 960 nm semiconductor laser and the Xe lamp light simultaneously, is reported in this article. It was found that the upconversion emission spectra of 480.1, 519.0, 601.9 and 63..8 nm coincide with the common emission spectra. Meanwhile, the upconversion-excitation spectrum has three obvious peaks under two-color excitation, and they respectively correspond to the 856.0 nm upconversion ex-citation transition [1G4(Pr3.)→1I6(Pr3.) and 1G4(Pr3.)→3.1(Pr3.)], the 789.0 nm upconver-sion excitation transition 1G4(Pr3.)→3.2(Pr3.), and the 803.7 nm upconversion excitation transition 3.6(Pr3.)→1D2(Pr3.). The upconversion excitation transition 1G4(Pr3.)→1I6(Pr3.) is strong because its oscillator strength f = 23.040×10?6 is large, which results in a large peak appearing in the upconversion excitation spectrum. That is just the new interesting two-color excitation upconversion luminescence phenomenon of Pr(0.5)Yb(3.:ZBLAN induced by one laser and one continuous normal light simultaneously.

关键词： upconversion volumetric three-dimensional display two-color excitation.

The studies on neurogenesis induced by brain injury inadult ring dove

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Cell Research 1998年第2期8卷 151-158页

作者： ZUO MING XUE(Biology Department, beijing normal university, beijing100875,{3.) Biology Department Beijing Normal University Beijing China

It was the first time demonstrated by us that the number of newborn neurons was increajsed after making lesion in forebraill of adult ring dove (Streptopelia risoria)by means of autoradiography and *** in the adult avian is restricted to the telencephalon. In doves with bilateral electrolytic lesion of nucleus ectostriatum (E), the mean number of proliferating cells in the lateral ventricular zone (LVZ) and newborn neurons in the forebrain increased by 1.95 times and 2.3.times respectively as compared with that in intact doves. The most relllarkable increase of neurogenesis induced by nucleus ectostriatum lesions was found at the anteriorposterior level 3.(L3., where the lesion site was *** results showed that the electrolytic brain lesion altered the distribution pattern of proliferating cells in theLVZ and resulted in increase of the number of newborn neurons in the non-VZ areas of forebrain. The changes in number and distribution pattern of proliferating cells in LVZ and newborn neurons in forebrain may be dependent on site of lesion. Studies on the relationship between proliferating cells in LVZ and newly generated neurons in non-VZ areas may help to understand the mechanism of brain plasticity and development.

关键词： Autoradiography neurogenesis brain lesion ring dove

Synthesis of superheavy nuclei with ^(23.)U target

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Science china(Physics,Mechanics & Astronomy) 2009年第10期52卷 1482-1488页

作者： LIU ZuHua1,3.& BAO JingDong2,4 1 Key Laboratory of Beam Technology and Material Modification of Ministry of Education,beijing normal university,beijing 100875,china 2 Department of Physics,beijing normal university,beijing 100875,china 3.12} Institute of Atomic Energy,beijing 102413.china 4 Center of Theoretical Nuclear Physics,National Laboratory of Heavy Ion Accelerator of Lanzhou,Lanzhou 73.000,china Key Laboratory of Beam Technology and Material Modification of Ministry of Education Beijing Normal University Beijing China china Institute of Atomic Energy Beijing China Department of Physics Beijing Normal University Beijing China Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou China

The production of superheavy nuclei with Z=108-116 via hot fusion reactions of the neutron-rich projectiles with 23.U target is systematically *** results show that the production cross sections of superheavy nuclei do not decrease monotonously as the atomic number Z *** cross sections of the superheavy nuclei at Z = 112 and 115 are enhanced as compared with the whole Z-trend in synthesis of the superheavy nuclei,which clearly illustrates that the reactions with large negative Q-value and shell correction are more favorable to synthesize superheavy nuclei.

关键词： superheavy nuclei fusion reaction cross section 23.U target

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

Theoretical studies on the mechanism of α-hydroxy-acid gas-phase elimination process and its substituent effect

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Chinese Journal of Chemistry 1997年第4期15卷 313-317页

作者： SONG,Wei-Ping HE,Shao-Ren FU,Xiao-YuanDepartment of Chemistry,beijing normal university,beijing 100875,china Department of Chemistry Beijing Normal University Beijing 100875 China

The α-hydroxy-acid gas-phase elimination process has been studied theoretically by HF/*** calculated results can be summed up as follows:(1) The elimination process is a stepwise *** the first step,a 3.membered ring intermediate is formed via a 5-membered ring transition state;while the product is formed in the second step via a 3.membered ring transition state.(2) The obtained results of the substituent effect show that the increase of electronic donation of the alkyl groups is favorable for the *** substituents which show the electron-withdrawing inductive effect (e.g.-Cl,-CN,-CF3. are unfavorable for this process.

关键词： α-Hydroxy-acid gas-phase elimination mechanism

Landscape patterns and their evolutions in　the suburban ecotone──A case study of the eastern suburb of beijing

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Journal of Environmental Sciences 1994年第3期6卷 277-286页

作者： Yang Jurong,Zhang Hongmei,Huang Yi Institute of Environmental Science,beijing normal university,beijing 100875,china

The characteristics and evolutions of the landscape patterns in the suburban ecotone are studied on the basis of landscape-ecological maps of different years derived from the corresponding aerial photos The relationship between landscape patterns and urban economical development is ana- lyzed. The diversity index is used to characterize the features of the landscape patterns in the ecotone and define the location of Sharp change.

关键词： suburban ecotone landscape patterns diversity index.

Matrix calculation of high-dimensional cross product and its application in automatic recognition of the endmembers of hyperspectral imagary

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Science china(Information Sciences) 2011年第1期54卷 197-203页

作者： GENG XiuRui1,ZHAO YongChao1,LIU SuHong2 & WANG FuXiang3.1Key Laboratory of Technology in Geo-spatial Information Processing and Application System, Institute of Electronics,Chinese Academy of Sciences,beijing 100080,china 2State Key Laboratory of Remote Sensing Science,Jointly Sponsored by beijing normal university and the Institute of Remote Sensing Applications of Chinese Academy of Sciences, {3. of geography,beijing normal university,beijing 100875,china 3.3. of Electronics and Information Engineering,Beihang university,beijing 100191,china Key Laboratory of Technology in Geo-spatial Information Processing and Application System Institute of Electronics Chinese Academy of Sciences Beijing China State Key Laboratory of Remote Sensing Science Jointly Sponsored by beijing normal university and the Institute of Remote Sensing Applications of Chinese Academy of Sciences School of Geography Beijing Normal University Beijing China school of Electronics and Information Engineering Beihang University Beijing China

This paper gives the definition of the high-dimensional cross product and its calculation by extending the 3.D cross product definition into the high-dimensional vector *** on the properties of the cross product,the volume variance index(VVI)is proposed to be used in extracting automatically the endmembers of the hypherspectral imagery which eliminates the shortcoming of the traditional method of using simplex only where the extraction results were easily impacted by the abnormal pixels.A case study of endmembers extraction experiment using the VVI method with the AVIRIS data for Cuprite has shown a very good result.

关键词： endmember simplex hyperspectral imagery cross product

△-tame quasi-hereditary algebras

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Science china Mathematics 2007年第2期50卷 240-252页

作者： Yun-ge XU & Ying-bo ZHANG Faculty of Mathematics and Computer Science, Hubei university, Wuhan 43.062, china school of Mathematics Sciences,{3., beijing 100875, china Faculty of Mathematics and Computer Science Hubei University Wuhan China school of Mathematics Sciences Beijing Normal University Beijing China

Let (K, M,H) be an upper triangular bimodule problem. Briistle and Hille showed that the opposite algebra A of the endomorphism algebra of a projective generator P of the matrices category of (K., M, H) is quasi-hereditary, and there is an equivalence between the category of△-good modules of A and Mat(K, M). In this note, based on the tame theorem for bimodule problems, we show that if the algebra A associated with an upper triangular bimodule problem is of△-tame representation type, then the category F(△) has the homogeneous property, i.e. almost all modules in F(△) are isomorphic to their Auslander-Reiten translations. Moreover, if (K, M,H)is an upper triangular bipartite bimodule problem, then A is of△-tame representation type if and only if F(△) is homogeneous.

关键词： bimodule problem quasi-hereditary algebra △-tameness homogeneity.

On weak solutions for an image denoising-deblurring model

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Applied Mathematics(A Journal of Chinese Universities) 2009年第3期24卷 269-281页

作者： HUANG Hai-yang JIA Chun-yan HUAN Zhong-dan school of Mathematical Sciences,beijing normal {3. Laboratory of Mathematics and ComplexSystems,Ministry of Education,beijing 100875,china school of Mathematical Sciences Beijing Normal University Beijing China Laboratory of Mathematics and Complex Systems Ministry of Education Beijing China

A new denoising-deblurring model in image restoration is proposed,in which the regularization term carries out anisotropic diffusion on the edges and isotropic diffusion on the regular *** existence and uniqueness of weak solutions for this model are proved,and the numerical model is also *** with the TV diffusion,this model preferably reduces the staircase appearing in the restored images.

关键词： image restoration deblurring-denoising integro-differential equation weak solution