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A Stochastic Extension of Macroscopic Stability Criterion of Nonequilibrium Steady State in Chemical Reaction Systems Governed by Master Equation

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Chemical Research in Chinese Universities 1990年第4期6卷 360-369页

作者： Luo Jiuli (department of chemistry, Sichuan{2., Chengdu)

By means of both the separation of the perturbation in accordance with characteristic parnmeters and the Kramers Moyal-expansion of the master equation, it is shown that the time derivative of the partial excess quantity of stochastic entropy due to the deviation from the most probable path is related to the responsibility of a system to the external macroscopic perturbations. This evolution rate of the partial excess stochastic entropy is equivalent to the partlal excess stochastic entropy production, as well as the stochastic excess entropy production rate based on the stochastic potential npproach. It appears also as an eqivalent quantity of the Gibbs excess entropy production for the Polsson distribution. The macroscopic stability of chemical reaction systems is dominnted by this new stochastic quantity when the local equilibrium thermodynamics is broken down .

关键词： Macroscopic stability Nonegulllbrium steady states Master equation, Kramers-Moyal expansion, Separation of perturbation in accordance with characteristic parameters

Evolutionary pattern of the regulatory network for flower development:Insights gained from a comparison of two Arabidopsis species

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Journal of Systematics and Evolution 2011年第6期49卷 528-538页

作者： 1,2.Yang LIU 1,2.hun-Ce GUO 1Gui-Xia XU 1Hong-Yan SHAN 1Hong-Zhi KONG 1(State Key Laboratory of Systematic and Evolutionary Botany,Institute of Botany,Chinese Academy of Sciences,beijing 100093,China) 2.Graduate university of Chinese Academy of Sciences,beijing 100049,China) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (Graduate university of Chinese Academy of Sciences Beijing 100049 China)

Previous studies on Arabidopsis thaliana and other model plants have indicated that the development of a flower is controlled by a regulatory network composed of genes and the interactions among *** on the evolution of this network will therefore help understand the genetic basis that underlies flower *** this study,by reviewing the most recent published work,we added 31 genes into the previously proposed regulatory network for flower ***,the number of genes reached *** then compared the composition,structure,and evolutionary rate of these genes between *** and one of its allies,*** found that two genes(FLC and MAF2.show 1:2.and 2.2.relationships between the two species,suggesting that they have experienced independent,post-speciation *** the remaining 58 genes,35(60.3%)have diverged in exon-intron structure and,consequently,code for proteins with different sequence features and *** evolutionary analyses further revealed that,although most floral genes have evolved under strong purifying selection,some have evolved under relaxed or changed constraints,as evidenced by the elevation of nonsynonymous substitution rates and/or the presence of positively selected *** together,these results suggest that the regulatory network for flower development has evolved rather rapidly,with changes in the composition,structure,and functional constraint of genes,as well as the interactions among them,being the most important contributors.

关键词： Arabidopsis evolution flower development regulatory network.

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空间刚架结构的广义逆力法

力学季刊 2004年第1期25卷 38-45页

作者：刘西拉王开健张春俊上海交通大学土木工程系上海200030 北京清华大学土木工程系北京100084 中元国际工程设计研究院北京100089

在结构计算中,根据算法中所采用的基本未知量的不同,结构分析方法可以分为力法、位移法和混合法。其中位移法由于适宜计算机处理而在结构计算领域得到了广泛的应用,经典力法相比之下应用就远不如位移法普遍,虽然力法本身在力学上有其独... 详细信息

在结构计算中,根据算法中所采用的基本未知量的不同,结构分析方法可以分为力法、位移法和混合法。其中位移法由于适宜计算机处理而在结构计算领域得到了广泛的应用,经典力法相比之下应用就远不如位移法普遍,虽然力法本身在力学上有其独特的优势。广义逆矩阵做为一种较新的数学工具,自二十世纪五十年代诞生以来正日益表现出越来越旺盛的生命力。广义逆力法就是一种基于力法和广义逆矩阵理论的新的迭代算法。这种算法是一种完全适合计算机处理的力法方法。该算法的思路以及对于求解线弹性空间刚架结构问题的具体公式均在文中给出并给出了算例。从算例计算结果可以看到广义逆力法有着较好的计算效率和计算精度。该算法的提出为力法在计算机计算领域的应用开拓了新的发展空间。该算法在材料非线性问题和结构并行计算方面也有着较好的应用前景。

关键词：广义逆矩阵广义逆力法空间刚架结构结构计算结构分析结构力学

Study on Enhancement Effect of Cavitation Caused by HIFU Piezoelectricity Transducer

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稀有金属材料与工程 2006年第S3期 527-529页

作者： Xinnan Fan~1 Changping Zhu~1 Shichuan He~2.Minglei Shan~2.Jiacai Chen~2.(1.department of Computer & Information Engineering,Hohai university,Changzhou 2.302.,China) (2.State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Hohai university,Nanjing 2.0098,China)

An orthogonal ultrasonic irradiation system consisting of HIFU with frequency at 1.05 MHz combined with ultrasound with frequency at 2. kHz was applied in this *** of cavitation was detected by pH-value measurement and conductance *** result shows that the effect of cavitation caused by ultrasound with frequency at 2. kHz is greatly enhanced by HIFU piezoelectricity transducer with frequency at 1.05 MHz.

关键词： HIFU piezoelectricity transducer enhanced cavitation effect orthogonal ultrasonic irradiation

Effcient generation of multi-photon W states by joint-measurement

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Progress in Natural Science:Materials International 2008年第1期 119-122页

作者： Wenhu Xu a ,Xin Zhao a ,Guilu Longa ,b,* aKey Laboratory for Atomic and Molecular Nanosciences and department of Physics,tsinghua{2.,beijing 100084,China btsinghua National Laboratory for Information Science and Technology,tsinghua{2.,beijing 100084,China

We propose an effcient scheme to generate multi-photon entangled W state from two-qubit Einstein–Podolsky–Rosen pairs by mea- surements and follow-up local *** discuss the effciency of the scheme under realistic con... 详细信息

关键词： W-state Quantum entanglement Multi-photon W-state generation

Diagenesis and Porosity of the Cambrian-Ordovician Carbonate Shoal Fades at Yangjiaping, Shimen, Hunan

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Acta Geologica Sinica(English Edition) 2000年第1期74卷 29-45,116-117页

作者： ZHANG Xiulian, WANG Yinghua and CHEN Xiaolong department of Geology, Peking university,{2. 100871 Peking Univ Dept Geol Beijing 100871 Peoples R China

Upper Cambrian-Lower Ordovician shoal-facies carbonate rocks are well developed in the Yangjiap-ing section, Shimen, Hunan, and their types are also highly varied. There are both monomictic shoal-facies rocks (e.g. sparite oolitic limestone and sparite calcarenite) and polymictic shoal-facies rocks (e.g. grainstone, whose grain types include sand- and pebble-sized fragments, bioclasts, oolites, algal mats etc.). What is different is that the Upper Cambrian shoal-facies rocks have been mostly strongly dolomitized into shoal-facies dolomite with various residual textures. This paper presents an in-depth study of various kinds of diagenesis and pore space evolution occurring in this section and suggests that the diagenetic sequences of shoal-facies rocks in the study area is dominantly of retrogressive type.

关键词： rock types dolomitization dissolution diagenetic sequence

The sloshing of stratified liquid in a two-dimensional rectangular tank

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Science China(Physics,Mechanics & Astronomy) 2011年第1期54卷 2-9页

作者： WU GuoXiong1,2.1 State Key Laboratory of Ocean Engineering,College of Naval Architecture,Ocean and Civil Engineering,Shanghai Jiao Tong university,Shanghai 2.02.0,China 2.department of Mechanical Engineering,university College London,Torrington Place,London WC1E 7JE,UK State Key Laboratory of Ocean Engineering College of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University Shanghai China department of Mechanical Engineering University College Londo London UK

The sloshing of inviscid liquid of stratified density in a rectangular tank is *** the flow is no longer irrotional,the governing equation is found to be quite different from the Laplace equation used for the liquid of constant *** particular it contains terms of mixed temporal and spatial *** problem is solved based on the variable separation method and Laplace transform for the constant Vaisala-Brunt *** is found that the stratification of density may have small effects on those natural frequencies associated with the constant density,but many new natural frequencies have appeared as a result of its effect.

关键词： sloshing density stratification resonance rectangular tank

A NEW CHARACTERIZATION OF FIXED MODES FOR DECENTRALIZED CONTROL SYSTEMS

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Systems Science and Mathematical Sciences 1989年第2期2卷 161-169页

作者：储德林 tsinghua university BeijingChina

In this paper,a study of the characterization of fixed modes in decentralized control ismade.A new sufficient and necessary condition for the existence of fixed modes is obtained by meansof the generalized eigenvalue theory of matrix pairs,and the computability of the new condition *** results show that fixed modes can be computed in a reliable and efficient manner.

关键词： Decentvalized control Fixed mode Matrex pair Generalized eigenvalue Yegulavity

A　STUDY　ON　THE　MULTI—RIGID—BODY　MODEL　FOR　HUMAN　WALKING IN　SWING　PHASE

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Chinese Journal of Biomedical Engineering(English Edition) 1995年第3期4卷 152-153页

作者： $$$$Dong Yuzhen Jin Dewen Zhang Jichuan Bai Caiqin(department of precision Instruments and Machanology,tsinghua{2.,beijing 100084,China)

ＡＳＴＵＤＹＯＮＴＨＥＭＵＬＴＩ—ＲＩＧＩＤ—ＢＯＤＹＭＯＤＥＬＦＯＲＨＵＭＡＮＷＡＬＫＩＮＧＩＮＳＷＩＮＧＰＨＡＳＥＡＳＴＵＤＹＯＮＴＨＥＭＵＬＴＩ—ＲＩＧＩＤ—ＢＯＤＹＭＯＤＥＬＦＯＲＨＵＭＡＮＷＡＬＫＩＮＧＩＮ... 详细信息

ＡＳＴＵＤＹＯＮＴＨＥＭＵＬＴＩ—ＲＩＧＩＤ—ＢＯＤＹＭＯＤＥＬＦＯＲＨＵＭＡＮＷＡＬＫＩＮＧＩＮＳＷＩＮＧＰＨＡＳＥＡＳＴＵＤＹＯＮＴＨＥＭＵＬＴＩ—ＲＩＧＩＤ—ＢＯＤＹＭＯＤＥＬＦＯＲＨＵＭＡＮＷＡＬＫＩＮＧＩＮＳＷＩＮＧＰＨＡＳＥＤｏｎｇＹｕｚ...

关键词： SWING PHAS