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In vivo and in vitro biomineralization in the presence of the inner-shell film of pearl oyster

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Acta Oceanologica Sinica 2011年第1期30卷 87-93页

作者： YAN Zhenguang MENG Wei LIU Zhengtao YANG Suwen LIU Xiaojun SUN Juan XIE Liping zhang Rongqing Institute of Marine Biotechnology Department of Biological Sciences and BiotechnologyTsinghua University Beijing 100084 China Chinese Research Academy of Environmental sciences Beijing 100012 China Protein Science Laboratory of the Ministry of Education Tsinghua University Beijing100084 China

The inner shell surface is the biomineralization site in shell formation and an inner-shell film covers it. This surface is composed of two regions： an outer calcitic region and an inner aragonitic region. In this study, some amalgamated calcite crystals were found in the calcitic region and some aragonitic ＂imprints＂ were found in the central part of the aragonitic region. The ＂imprints＂ are probably the trace of mantle cells that adhered to the inner shell surface when the shell was produced. Furthermore, to build a novel in vitro biomineralization system, the inner-shell film was detached from the shell and introduced to the calcitic crystallization solution. Crystallization experiments showed that nacre proteins could induce aragonite crystals in the novel system but inhibited calcite growth in the absence of the inner-shell film. These data suggested that the inner-shell film may induce aragonite growth in vivo by combining nacre proteins.

关键词： biomineralization inner shell surface inner-shell film nacre Pinctada fucata

The role of aerial algae in the formation of the landscape of the Yunnan Stone Forest,Yunnan Province, china

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Science china Earth sciences 2004年第9期47卷 846-864页

作者： TIAN Youping1,3, zhang Jie2. SONG Linhua1 & BAO Haosheng2.1. Institute of Geographic {2. and Natural Resources Research, Chinese Academy of {2., beijing 100101, china 2. department of Geography, Nanjing University, Nanjing 2.0093, china 3. School of Earth {2. and Resources, china University of Geo{2., beijing 100083, china Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China department of Geography Nanjing University Nanjing 210093 China School of Earth sciences and Resources China University of Geosciences Beijing 100083 China

Aerial algae on the surface of carbonate rocks at the Stone Forest, Shilin County, Yunnan Province, china, and their bioerosion were investigated in the field and studied in the laboratory in detail. Through the observation, identification and statistics of more than one hun- dred algal samples and rock samples with the optical microscopes (stereomicroscope, biological microscope) and the scanning electronic microscope (SEM), the relationships between erosional forms on the surface of the Stone Forest and algae and/or algal communities and the genetic mechanism for the formation of erosional forms were analyzed. It is suggested that aerial algae play an active role in bioerosive processes that may affect the formation of karst erosional forms. These effects include both direct and indirect ones. The direct effect is the initiative control (algal shape-controlling role) of algae on the formation of karst forms of various scales, mostly mi- cro-scale (10-3m) and minor-scale (10-3-10-1m) erosional forms. The algal shape-controlling roles can be divided into the algal individual shape-controlling role and the algal community shape-controlling role. The former mostly controls the formation of micro-scale erosional forms, while the latter mostly controls the formation of micro-scale and smaller minor-scale erosional forms. The indirect effect refers to the promoting role of algae in the formation of karst forms, which may affect the formation of karst forms of all types and scales. The bioerosion of algae accelerates the weathering process of the whole Stone Forest karst landforms.

关键词： aerial algae, bioerosion, the Stone Forest, Yunnan Province, china.

A Rationalization of Sympathetic Nucleation-Ledgewise Growth Theory of Bainite Transformation in Fe-C Alloys

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Journal of Materials Science & Technology 2001年第4期17卷 433-438页

作者： Zhigang YANG, Chi zhang, Hongsheng FANG, Jinbo YANG, Bingzhe BAI and Jiajun WANG department of Materials Science and Engineering, {2. University beijing 100084, china Tsing Hua Univ Dept Mat Sci & Engn Beijing 100084 Peoples R China

Based on the classic diffusion controlled nucleation and goth theory, the sympathatic nucleation- ledgewise growth mechanism of bainite was studied theoretically for low carbon Fe-C alloys. The rationality of the occurrence of sympathetic nucleation on the terraces of ledges compating with lateral ledge growth and other sites nucleation was demonstrated by the present work quantita- tively The calculations indicated that low reaction temperatures and high carbon concentrations may favor the sympathetic nucleation, thus accounting for the formation of multilayer structures of bainite.

关键词： A Rationalization of Sympathetic Nucleation-Ledgewise Growth Theory of Bainite Transformation in Fe-C Alloys Fe

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Lp shape deformation

Science china(Information sciences) 2012年第5期55卷 983-993页

作者： GAO Lin1,zhang GuoXin 1 & LAI YuKun 2.1 {2. of Computer Science and Technology,tsinghua University,beijing 100084,china 2.School of Computer Science and Informatics,Cardiff University,Wales CF2. 3AA,UK 1. department of Computer Science and Technology Tsinghua University Beijing 100084 China2. School of Computer Science and Informatics Cardiff University Wales CF24 3AA UK

Shape deformation is a fundamental tool in geometric *** methods consider preserving local details by minimizing some energy functional measuring local distortions in the L 2.*** strategy distributes distortions quite uniformly to all the vertices and penalizes ***,there is no unique answer for a natural deformation as it depends on the nature of the *** by recent sparse signal reconstruction work with non L 2.norm,we introduce general L p norms to shape deformation;the positive parameter p provides the user with a flexible control over the distribution of unavoidable *** with the traditional L 2.norm,using smaller p,distortions tend to be distributed to a sparse set of vertices,typically in feature regions,thus making most areas less distorted and structures better *** the other hand,using larger p tends to distribute distortions more evenly across the whole *** flexibility is often desirable as it mimics objects made up with different *** specifying varying p over the shape,more flexible control can be *** demonstrate the effectiveness of the proposed algorithm with various examples.

关键词： shape deformation Lp norm geometric modeling

A stochastic policy search model for matching behavior

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Science china(Information sciences) 2011年第7期54卷 1430-1443页

作者： CHENG ZhenBo 1,2.zhang Yu 1 & DENG ZhiDong 1 1 State Key Laboratory on Intelligent Technology and Systems,tsinghua National Laboratory for Information Science and Technology,{2. of Computer Science,tsinghua University,beijing 100084,china 2.{2. of Computer Science and Technology,Zhejiang University of Technology,Hangzhou 310014,china 1. State Key Laboratory on Intelligent Technology and Systems Tsinghua National Laboratory for Information Science and Technology Department of Computer Science Tsinghua University Beijing 100084 China2. Department of Computer Science and Technology Zhejiang University of Technology Hangzhou 310014 China

The matching law is one of the basic empirical laws in decision theory,and it states that a subject’s preference to optional targets depends on which choices are *** this paper,we study the possible mechanisms that explain why subjects’ decisions often obey this *** the basis of reinforcement learning theory,we put forward a decision-making model in which the policy is updated by a policy parameter,and the model might be implemented in the brain through the prefrontal cortex and the basal ganglia neural *** on this model,an algorithm that satisfies the matching law is derived under some simple *** analysis and simulation results show that the decision behavior achieved by the algorithm obeys the matching *** addition,the matching behaviors in two classical experiments are reproduced using the *** results provide a reasonable strategy for the matching law and a useful computational tool for rewarded decision-making tasks.

关键词： policy model matching law reinforcement learning decision-making model

Estimation of LISS(local input-to-state stability) properties for nonlinear systems

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Science china(Technological sciences) 2010年第4期53卷 909-917页

作者： WU ShengYu,MEI ShengWei & zhang XueMin State Key Laboratory of Power Systems,department of Electrical Engineering,{2. University,beijing 100084,china 1. State Key Laboratory of Power Systems Department of Electrical Engineering Tsinghua University Beijing 100084 China

Compared with input-to-state stability(ISS) in global version,the concept of local input-to-state stability(LISS) is more relevant and meaningful in *** key of assessing LISS properties lies in investigating three main ingredients,the local region of initial states,the local region of external inputs and the asymptotic *** is the objective of this paper to propose a numerical algorithm for estimating LISS properties on the theoretical foundation of quadratic form LISS-Lyapunov *** developments of linear matrix inequality(LMI) methods,this algorithm is effective and powerful.A typical power electronics based system with common DC bus is served as a demonstration for quantitative results.

关键词： locally input-to-state stability LISS-Lyapunov function linear matrix inequality

Numerical Study of Thermal Performance of Phase Change Material Energy Storage Floor in Solar Water Heating System

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湖南大学学报（自然科学版） 2009年第S1期36卷 141-145页

作者： ZENG Ruo-lang,WANG Xin,zhang Yin-ping,DI Hong-fa,zhang Qun-li({2. of Building Science,tsinghua University,beijing 100084,china) department of Building Science Tsinghua University Beijing 100084 China

The conventional solar heating floor system contains a big water tank to store energy in the day time for heating at night,which takes much building space and is very *** order to reduce the water tank volume even to cancel the tank,a novel structure of integrated water pipe floor heating system using shape-stabilized phase change materials(SSPCM)for thermal energy storage was developed.A numerical model was developed to analyze the performance of SSPCM floor heating system under the intermittent heating condition,which was verified by our experimental *** thermal performance of the heating system and the effects of various factors on it were analyzed *** factors including phase transition temperature,heat of fusion,thermal conductivity of SSPCM and thermal conductivity of the decoration material were *** results show that tm and kd are the most import influencing factors on the thermal performance of SSPCM floor heating system,since they determine the heat source temperature and thermal resistance between SSPCM plates and indoor air,*** should be large to store enough thermal energy in the day time for nighttimes *** effects of kp can be ignored in this *** SSPCM floor heating system has potential of making use of the daytime solar energy for heating at night efficiently in various climates when its structure is properly designed.

关键词： phase change material energy storage solar water heating

A note on n-edge chromatic number

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Chinese Science Bulletin 1997年第23期42卷 1952-1954页

作者： SUN Liang and zhang Zhongfu1. department of Applied Mathematics, {2. Institute of Technology, {2. 100081, china 2. Institute of Applied Mathematics, Lanzhou Institute of Railway, Lanzhou 730070, china department of Applied Mathematics Beijing Institute of Technology Beijing 100081 China

ALL graphs appearing in this note are simple. A graph with p vertices and q edges will becalled a (p, q )-graph. The maximum degree of G is denoted by Δ(G).Let n≥2.be an integer. The n-edge chromatic number X_n (G) of a simple graph G is theminimum cardinality of a set of colors with which one can assign the colors to the edges of Gsuch that the edges on a path of length less than or equal to n receive different *** aim of this note is to explore the bounds for X’_n (G) and X’_n (G) + X’_n (G). It is

关键词： graph complement n-edge chromatic number.

Orthogonally linear polarized lasers (I)——principle and devices

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Progress in Natural Science:Materials International 2005年第7期15卷 586-595页

作者： zhang Shulian and XU Ting (State Key Laboratory of Precision Measurement Technology and Instruments, department of Precision Instruments, {2. University, beijing 100084, china) State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision Instruments Tsinghua University Beijing 100084 China

Two kinds of orthogonally polarized lasers, i. e. Zeeman dual-frequency lasers and four-frequency ring lasers (laser gyros) have been developed since the invention of lasers, in which circularly polarized lights oscillate. This paper summarizes recent progress of the study on orthogonally linear polarized lasers with the standing wave cavity. Firstly, the expression of producing orthogonally linear polarized lights in standing wave cavity, i. e. laser frequency splitting, is given. Almost all the birefringence effects made in laser cavity are used to produce orthogonally linear polarized lights. The effect includes quartz crystal birefringence effect, calcite birefringence effect, stress (photo-elastic) birefringence effect and electro-optical birefringence effect. Secondly, several physical phenomena of orthogonally linear polarized lasers are discovered such as aberrance of frequency splitting curves caused by optical activity of quartz crystal, order-passing of longitudinal modes with frequency splitting and strong modes competition. Finally, because the traditional Zeeman dual frequency laser cannot output frequency difference larger than 3 MHz, the approaches of obtaining larger frequency difference are studied. The sequential results, several kinds of orthogonally polarized lasers, are described, such as birefringence dual frequency lasers outputting a frequency difference from 40 MHz to hundreds of megahertz, birefringence-Zeeman dual frequency lasers outputting a frequency difference from 1 MHz to hundreds of megahertz, the LD pumped YAG birefringence dual frequency laser outputting frequency difference of several gigahertz, and the lasers whose longitudinal mode spacing is c/4L instead of c/2. .

关键词： orthogonally polarized laser dual frequency laser intra-cavity birefringence Zeeman effect photo-elastic birefringence electro-optical birefringence frequency splitting.