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Theoretical model of particle orientation distribution function in a cylindrical particle suspension subject to turbulent shear flow

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Progress in Natural Science:Materials International 2006年第1期16卷 16-20页

作者： zhang Lingxin1, LIN Jianzhong1and zhang Weifeng {2..department of Mechanics, State Key Laboratory of Fluid Power Transmission and Control, Zhejiang university, Hangzhou 31002., china 2. Institute of Marine and Coastal sciences, Rutgers university, New Brunswick, New Jersey, USA) [a]department of Mechanics State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou China [b]Institute of Marine and Coastal sciences Rutgers University' New Brunswick New Jersey USA

The equation for the orientation probability function of slender cylindrical particles suspended in planar turbulent flows was investigated. After ensemble averaging, the equations for the mean and fluctuating probability function were derived. The equation for the fluctuating probability function appearing in the equation of mean probability function was solved by using the method of characteristics analysis. The orientational dispersion terms due to the random motion of cylindrical particles in the equation of mean probability function are related to the mean probability function and the Lagrangian fluid velocity correlations. The evolution of the mean probability function was described by a modified oriental ion-space-convection equation, where the dispersion terms account for the randomizing effect of the turbulence.

关键词： dispersion cylindrical particle suspensions turbulent flow probability function.

A study of two-dimensional magnetic polaron

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Science china(Physics,Mechanics & Astronomy) 2006年第4期49卷 421-429页

作者： LIU Tao1, zhang Huaihong1, FENG Mang1,2.& WANG Kelin1,3 1. School of Science, Southwest university of Science and Technology, Mianyang 62.010, {2. 2. Wuhan Institute of Physics and Mathematics, Chinese Academy of sciences, Wuhan 430070, {2. 3. department of Modern Physics, university of Science and Technology of {2., Hefei 2.002., {2. School of Science Southwest University of Science Technology Mianyang 621010 China Wuhan Institute of Physics Mathematics Chinese Academy of Sciences Wuhan 430070 China department of Modern Physics University of Science Technology of china Hefei 230026 China

By using the variational method and anneal simulation, we study in this paper the self-trapped magnetic polaron (STMP) in two-dimensional anti-ferromagnetic material and the bound magnetic polaron (BMP) in ferromagnetic material. Schwinger angular momentum theory is applied to changing the problem into a coupling problem of carriers and two types of Bosons. Our calculation shows that there are single-peak and multi-peak structures in the two-dimensional STMP. For the ferromagnetic material, the properties of the two-dimensional BMP are almost the same as that in one-dimensional case; but for the anti-ferromagnetic material, the two-dimensional STMP structure is much richer than the one-dimensional case.

关键词： self-trapped magnetic polaron, bound magnetic polaron, impurity potential, anti-ferromagnet.

Geomorphologic evolution and environmental changes in the Shaluli Mountain region during the Quaternary

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Chinese Science Bulletin 2005年第1期50卷 52-57页

作者： ZHOU Shangzhe1,2. XU Liubing1, CUI Jianxin1, zhang Xiaowei1 & ZHAO Jingdong1 1. National Laboratory of Western china’s Environmental Systems of Ministry of Education of china and department of Geography, Lan- zhou university, Lanzhou 730000, china 2. department of Geography, South china Normal university, Guang- zhou 510631, china National Laboratory of Western china''s Environmental Systems of Ministry of Education of china and {2. of Geography Lanzhou University Lanzhou 730000 China department of Geography South China Normal University Guangzhou 510631 China

Geologic and geomorphologic evidence from the Shaluli Mountain indicates that the planation surface that formed in the Late Tertiary disintegrated during the Late Pliocene-Early Quaternary. At the same time, rift ba- sins appeared on some parts of the planation surface, and began to accumulate fluvial-lacustrine sediment. These are interpreted as being the response of this region to Phase-A of the Qingzang Tectonic Movement. After this, the Shaluli Mountain continued to rise in several pulses. Faulting and incision by some large tributaries of the Jinsha and Yalong Rivers resulted in several rift river valleys and the earliest terraces. Generally, the planation surface in this region had been uplifted to about 3500—3700 m a.s.l. no later than 550—600 ka BP, after the Kunlun-Huanghe Tectonic Move- ment, and coupled with global glacial climate, and resulted in the earliest glaciation recognized so far in the Hengduan Mountains. At the same time, loess was deposited in the Ganzi area of the northern Shaluli Mountain. During the last glacial period, the Shaluli Mountain approached its present altitude and developed several large ice caps, such as the Daocheng Ice Cap and Xinlong Ice Cap, as well as several huge valley glaciers. These paleoglaciers produced some of the most spectacular glacial topography on the Tibetan Pla- teau.

关键词：地形学环境变化 Shaluli山脉展平面西藏高原 ESR-年代测定

KTN thin films prepared by pulsed laser deposition on transparent single crystal quartz(100)

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Science china(Physics,Mechanics & Astronomy) 2005年第1期48卷 33-43页

作者： WANG Xiaodong, PENG Xiaofeng & zhang Duanming Laboratory of Phase Change and Interfacial Transport Phenomena, department of Thermal Engineering, {2., Beijing 100084, china department of Physics, Huazhong university of Science and Technology, Wuhan 430074, china 1. Laboratory of Phase Change and Interfacial Transport Phenomena Department of Thermal Engineering Tsinghua University 100084 Beijing China 2. department of Physics Huazhong University of Science and Technology 430074 Wuhan China

Using the Sol-Gel method to produce the KTN ultrafine powder and the sintering technique with K2. atmosphere to prepare KTN ceramics as the targets instead of the KTN single crystal, highly oriented KTN thin films were produced on the transparent single crystal quartz (100) by the pulsed laser deposition (PLD). Since the thermal stress sustained by the quartz is relatively small, the limit temperature of the quartz substrates(300℃) is much lower than that of the P-Si substrates (560℃); the prepared thin film is at amorphous state. Increasing the pulsed laser energy density in the process incorporated with annealing the film after deposition at different temperatures converts the amorphous films into crystal. The optimal pulsed laser energy density and annealing temperature were 2.0 J/cm2.and 600℃, respectively. A discussion was made to understand the mechanism of film production at relatively low substrate temperature by PLD and effects of the annealing temperatures on the forming of the perovskite phase, and optimal conditions for the orientation of the crystal grain.

关键词： PLD technology, KTN thin film, single crystal quartz, pulsed energy density, annealing, perovskitephase.

Preparation of QTi4.3-4Graghite Composite by Semi-solid Casting Technology

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Journal of Wuhan university of Technology(Materials Science) 2005年第4期20卷 69-72页

作者：张鹏 department of Mechanical Engineering Beijing Jiaotong University Beijing 100044 China

The electromagnetic-mechanical stirring technology was employed for preparing QTi4.3-4 graghite composite slurry,and QTi4.3-4 graghite composite with uniform distribution of graphite particles was prepared uring the semi-solid casting technology *** structure of this QTi4.3-4graphite composite was studied and the condition for uniform distribution of graphite particles was *** experimental results show that there exists a linear relationship between the solid fraction and the stirring temperature of QTi4.3-4graphite *** the decreasing of stirring temperature,the solid fraction of QTi4.3-4 graghite slurry increases *** casting,with the increasing of solid fraction of QTi4.3-4 graphite *** agglomeration of graphite particles is removed *** the solid fraction is higher than 40%,graphite particles can distribute evenly in QTi4.3-4 graghite composite.

关键词： semi-solid casting technology distribution of graphite particles solid fraction

Rank of loop, constraint degree of path, coupling degree of graph and their application

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Progress in Natural Science:Materials International 2005年第2期15卷 79-85页

作者： YANG Tingli1*, LUO Yufeng2. zhang Ce3 and YAO Fanghua1(1. SINOPIC Jinling Petrochemical Corp., Nanjing 2.0037, china 2. {2. of Mechanical Engineering, Nanchang university, Nanchang 33002., china 3. {2. of Mechanical Engineering, Tianjin university, Tianjin 300072. china) SINOPIC Jinling Petrochemical Corp. Nanjing 210037 China. department of Mechanical Engineering Nanchang University Nanchang 330029 China. department of Mechanical Engineering Tiánjin University Tianjin 300072 China

Some new concepts (rank of a loop, degree of freedom of a graph, path unit and ordered path arrangement, constraint degree of path, coupling degree of a graph, basic graph, etc.), formulas, and algorithms, are proposed in this paper. Based on these concepts, a new systematic theory and practical method for the design of topological structure, kinematics and dynamics of mechanical systems is established. Some conjectures and problems needed to be researched are also put forward. The concepts, formulae and algorithms presented in this paper will find wide potential applications.

关键词： rank of loop degree of freedom of graph constraint degree of path coupling degree of graph

Formation and Evolution of Ancient Lakes on South Coast Plain of Laizhou Bay

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Chinese Journal of Population,Resources and Environment 2005年第4期3卷 26-32页

作者： Han Mei 1, Zhou Baohua 2. Yang Peilin 1,Gao Guiqin 1 & zhang Weiying 1 1. department of Geography, Shandong Normal {2., Jinan 2.0014, china 2. department of Geography, Jinan {2., Jinan 2.0001, china department of Geography Shandong Normal University Jinan 250014 China department of Geography Jlnan University Jinan 250001 China

Based on the data of historical geography, the analysis of the stratigraphic section, and the textual research of place names and satellite photographic interpretations, the authors study the formation and evolution of ancient lakes on the south coast plain of Laizhou Bay where there were once three lakes: Judian Lake, Qingshuibo Lake and Biehua Lake. All the lakes formed 6000 years ago evolved from the lagoons near the estuary and went through two periods, the golden age in the Middle Holocene and the shrinking age in the Late Holocene. The disappearance of the lakes resulted from the drying climate, the migration of the river courses and the activities of human beings. Among the three reasons, the migration of the river courses is the main one.

关键词： ancient lake cause historical evolution south coast plain of Laizhou Bay

Quantum statistical entropy corresponding to cosmic horizon in five-dimensional spacetime

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Science china(Physics,Mechanics & Astronomy) 2008年第2期51卷 140-146页

作者： ZHAO Ren1,2.& zhang ShengLi1 1 department of Applied Physics, Xi’an Jiaotong {2., Xi’an 710049, china 2.department of Physics, Shanxi Datong {2., Datong 037009, china department of Applied Physics Xi’an Jiaotong University Xi’an 710049 China department of Physics Shanxi Datong University Datong 037009 China

The generalized uncertainty relation is introduced to calculate the quantum statis-tical entropy corresponding to cosmic horizon. By using the new equation of state density motivated by the generalized uncertainty relation, we discuss entropies of Bose field and Fermi field on the background of five-dimensional spacetime. In our calculation, we need not introduce cutoff. There is no divergent logarithmic term in the original brick-wall method. And it is obtained that the quantum statistical en-tropy corresponding to cosmic horizon is proportional to the area of the horizon. Further it is shown that the entropy corresponding to cosmic horizon is the entropy of quantum state on the surface of horizon. The black hole's entropy is the intrinsic property of the black hole. The entropy is a quantum effect. In our calculation, by using the quantum statistical method, we obtain the partition function of Bose field and Fermi field on the background of five-dimensional spacetime. We provide a way to study the quantum statistical entropy corresponding to cosmic horizon in the higher-dimensional spacetime.

关键词： quantum statistical entropy generalized uncertainty relation high-dimensional spacetime

Acid/alkali gated photochromism of two diarylperfluorocyclopentenes

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Science china Chemistry 2007年第5期50卷 581-586页

作者： CHEN ZiHui1, ZHAO ShengMin2. LI ZhongYu1, zhang Zhi1 & zhang FuShi1 1 The Key Lab of Organic Optoelectronics & Molecular Engineering of Ministry of Education, {2. of Chemistry, tsinghua university, Beijing 100084, china 2.Lab of Printing & Packing Materials and Technology-Beijing Area Major Laboratory, Beijing Institute of Graphic Communication, Beijing 100084, china 1. The Key Lab of Organic Optoelectronics & Molecular Engineering of Ministry of Education Department of Chemistry Tsinghua University Beijing 100084 China 2. Lab of Printing & Packing Materials and Technology-Beijing Area Major Laboratory Beijing Institute of Graphic Communication Beijing 100084 China

Two novel diarylfuorocyclopentenes, which underwent gated photochromism, were synthesized. It was found that the photochromic property of these diarylethenes could be switched by alternative addition of acids/alkalis,... 详细信息

关键词： photochromism, diarylethene, gated reactivity, pyridinium betaine