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再循环T细胞昼夜节律现象的数学模型

生物化学与生物物理进展 2001年第5期28卷 670-676页

作者：李方廷漆安慎北京大学物理系北京100871 北京师范大学物理系北京100875

根据人体和小鼠免疫细胞昼夜节律实验结果 ,提出皮质类激素对淋巴结和脾脏中T细胞再循环产生不同作用的假设 ,建立了皮质类激素作用下的T细胞在不同外周淋巴器官 (淋巴结、脾脏 )与血液之间再循环过程的数学模型 ,讨论了皮质类激素作用... 详细信息

根据人体和小鼠免疫细胞昼夜节律实验结果 ,提出皮质类激素对淋巴结和脾脏中T细胞再循环产生不同作用的假设 ,建立了皮质类激素作用下的T细胞在不同外周淋巴器官 (淋巴结、脾脏 )与血液之间再循环过程的数学模型 ,讨论了皮质类激素作用的强度、有关参量的取值范围和模型对参数的依赖性 .模型能够解释参与再循环的T细胞在淋巴结、脾脏与血液中的稳定振荡行为。

关键词：免疫细胞昼夜节律 T细胞再循环皮质类激素数学模型

Study on Cloud-Radiation Effect on Climate in Eastern Asia

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Advances in atmospheric Sciences 1992年第3期9卷 257-268页

作者：赵柏林张晓黎朱元竞department of Geophysics peking university {4. 100871 department of Geophysics Peking University Beijing 100871

In this paper, the decade data of meteorological satellite and surface meteorological observation of China have been analysed. The relationship between cloud and radiation has been studied. A set of empirical formulae of the ralationships between the albedo and cloud amount, the outgoing longwave radiation and cloud amount in Chinese different districts and different seasons has been deduced. They express simply the response of both planet reflectivity and earth-atmosphere outgoing longwave radiation to the change of cloud amount. So that the sensitivity of net radiation of the earth-atmosphere system to the change of cloud amount and the ratio of cloud reflective effect to greenhouse effect can be estimated. In this paper, the radiative process of the earth-atmosphere system, cloud and radiative balance and its effect on climate have been synthetically studied.

关键词： cloud greenhouse meteorological formulae reflective simply deduced radiative empirical absolute

Simulation of nuclei morphologies for binary alloy

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Science China Mathematics 2010年第11期53卷 2927-2936页

作者： LI DaMing1, & ZHANG PingWen2 1department of Mathematics, Shanghai Jiaotong university, Shanghai 20024., China 2Key Lab of Mathematics and Applied Mathematics, Center for Applied physics and Technology and School of Mathematical Sciences, peking university,{4., China 1. department of Mathematics Shanghai Jiaotong University Shanghai 200240 China2. Key Lab of Mathematics and Applied Mathematics Center for Applied Physics and Technology and School of Mathematical Sciences Peking University Beijing 100871 China

We study the critical nuclei morphologies of a binary alloy by the string method. The dynamic equation of the string, connecting the metastable phase (liquid) and stable phase (solid), is governed by Helmholtz free energy for the binary alloy system at a given temperature. The stationary string through the critical nucleus (saddle point) is obtained if the relaxation time of the string is su?ciently large. The critical nucleus radius and energy barrier to nucleation of a pure alloy with isotropic interface energy in two and three dimensions are calculated, which are consistent with the classical nucleation theory. The critical nuclei morphologies are sensitive to the anisotropy strength of interface energy and interface thickness of alloy in two and three dimensions. The critical nucleus and energy barrier to nucleation become smaller if the anisotropy strength of the interface energy is increased, which means that it is much easier to form a stable nucleus if the anisotropy of the interface energy is considered.

关键词： nucleation crystal morphology string method

Nuclear Effect on Gluon Distribution Function and Associate Production of J/Ψ and y with Large P_T in High Energy p-Fe Collision

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Chinese journal of nuclear physics 1995年第3期17卷 205-208页

作者： Zhang Shu~2 He Zhe-min~(1,2) Peng Hong-an~(1,3) Duan Chun-gui~21 CCAST(World Laboratory)P.O.Box 8730,Biejing 1000802 physics department,Hebei Normal university,Shijiazhuang,0500163 physics department,peking university,beijing 100871 Hebei Normal Univ Shijiazhuang China

With three theoretical models of nuclear effects on gluon distribution functions,the differentialcross sections and the total cross sections for associate production of J/ψ and γ with large P_T in high energyp-Fe co... 详细信息

关键词： Gluon distribution function Nuclear effect J/Ψ production

Response of global subtropical highs to the equatorial eastern Pacific SST anomaly

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Acta Oceanologica Sinica 1999年第2期18卷 203-214页

作者： Gong Daoyi and Wang Shaowu 1. department of Geophysics, peking university, beijing 100871, China (Received August 31, 1997 accepted March 30, 1998) department of Geophysics Peking University Beijing 100871 China

Based on the reanalysis data of global 500hPa geopotential height (NCEP NCAR CDAS-1) and tropical Pacific SSTs, the characteristics of global subtropical highs and their response to tropical eastern Pacific SST are investigated. Results show that global subtropical highs respond to SST consistently. Subtropical high intensity correlates to the 3 months leading SST maximally. The relationship between SST and 500hPa height stands out in low latitudes. The time for 500hPa height reaching maximuxn correlation to SST is 2 months later in latitude of 10 degree and 9 months in latitude of 30 degree than equatorial zone. And the response of atmospheric circulation over extratropic performs as wave train, and the response is more significant in the condition of warmer SST. Persistence of SSTs and subtropical highs changes obviously from season to season. Minimum persistence of subtropical highs in September and October may relate to the low persistence of SSTs in August and September.

关键词： Global subtropical highs equatorial eastern Pacific SST

Nuclear Matter Density Dependence of Nucleon Radius and Mass and Quark Condensates and Chiral Symmetry Restoration in the GCM of QCD

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Nuclear Matter Density Dependence of Nucleon Radius and Mass...

COLLISION OF WATER DROP ON WATER

CCAST“研究禁闭与退禁闭相变的连续场论途径”研讨会

作者： Yu-xin Liu department of physics,peking university,{4. 100871

＜正＞*** and mesonic degrees of freedom are essential in describing finite nuclei and nuclear matterEffective mass M*＜M0→nuclear structure＆reactionNucleon swell→EMC effectTheoretical Approaches:

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Acta Mechanica Sinica 1988年第4期4卷 297-304页

作者： Cai Yikun (department of physics,peking university,International Centre for Materials physics,Academia Sinica) 1. department of physics Peking University International Centre for Materials Physics Academia Sinica Beijing China

A series of experiments are performed to study the collision of a water drop with variousimpact velocities,ranged from 0 to 600 cm/s,onto a water *** kinds of phenomena have *** of them named"penetration"and"cleavage",were observed for low impact velocity(up to100 cm/s).Their common characteristics are that no obvious disturbances on the surface were observedduring the coUiding *** no splashing jets nor obvious crater were *** penetrationwe mean that a drop fallen into water becomes a ring,which penetrates the water smoothly with a velocityof several centimeters per *** the penetrating process no obvious change of its configurationwas *** falling height corresponding to penetration is proportional to volume of the *** periodicity of the falhng heights(corresponding to penetration)was *** named"cleavage"occurs when the impact velocity is other than that corresponding topenetration,then the drop cleaves into an"inverted cauliflower"after falling below the surface of *** does not *** diffusing and slowly expanding it vanishes in the vessel water several *** two kinds of phenomena,as we know,have not been reported *** the impact velocityapproaches or exceeds 100 cm/s,the third kind of phenomena,the splash,*** diameter anddepth of the crater occuring in the case of splash,together with the time for the crater to reach itsmaximum size,and the time for the rebounding column to begin to rise are given as functions of the fallingheight of the drop.

关键词： splash water drop penetration water surface impact

QCD Phase Transition in a Continuous Field Theory Approach

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QCD Phase Transition in a Continuous Field Theory Approach

The refined theory of transversely isotropic piezoelectric rectangular beams

International Workshop on Nuclear Dynamics in Heavy-ion Reactions and Neutron Stars

作者： Yuxin Liu department of physics peking university {4. 100871 China

＜正＞We review briefly the effects of the running coupling strength,the current quark mass,the density and the finite size of the matter on the QCD phase structure and its transition in the framework of Dyson-Schwinger equation approach of *** of our present results are *** results show that,besides the medium effects,the QCD phase structure and its transition depend also on the intrinsic

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Science China(physics,Mechanics & Astronomy) 2006年第4期49卷 473-486页

作者： GAO Yang1 & WANG Minzhong2 1. College of Science, China Agricultural university, beijing 100083, China 2. State Key Laboratory for Turbulence and Complex Systems and department of Mechanics and Engi- neering Science, peking university,{4., China 1. College of Science China Agricultural University Beijing 100083 China 2. State Key Laboratory for Turbulence and Complex Systems and department of Mechanics and Engineering Science Peking University Beijing 100871 China

The problem of deducing one-dimensional theory from two-dimensional theory for a transversely isotropic piezoelectric rectangular beam is investigated. Based on the piezoelasticity theory, the refined theory of piezoelectric beams is derived by using the general solution of transversely isotropic piezoelasticity and Lur'e method without ad hoc assumptions. Based on the refined theory of piezoelectric beams, the exact equations for the beams without transverse surface loadings are derived, which consist of two governing differential equations: the fourth-order equation and the transcendental equation. The approximate equations for the beams under transverse loadings are derived directly from the refined beam theory. As a special case, the governing differential equations for transversely isotropic elastic beams are obtained from the corresponding equations of piezoelectric beams. To illustrate the application of the beam theory developed, a uniformly loaded and simply supported piezoelectric beam is examined.

关键词： rectangular beams, the refined theory, piezoelectric, transversely isotropic.