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Analysis for twinning and slip in face-centered cubic crystals under axisymmetric co-deformation

Science China(Technological Sciences) 2006年第5期49卷 521-536页

作者： CHEN Zhiyong1,2, CAI Hongnian1, ZHANG Xinming2, WANG Fuchi1 & TAN Chengwen1,3.1. school of Material Science and engineering, beijing Institute of Technology,{3., China 2. school of Material Science and engineering, Central South university, Changsha 410083. China 3. school of Material Science and engineering, beijing university of Aeronautics and Astronautics, beijing 100083. China 1. school of Material Science and engineering Beijing Institute of Technology Beijing 100081 China 2. school of Material Science and engineering Central South University Changsha 410083 China 3. school of Material Science and engineering Beijing University of Aeronautics and Astronautics Beijing 100083 China

The maximum work principle of Bishop-Hill was developed to analyze the axisymmetric co-deformation in face-centered cubic crystals (f.c.c.) for twinning on {111} 112 and slip on {111} 110 systems. The influence of ξ , the ratio of critical re- solved shear stress for twinning to slip, on the yield stress states and corresponding active slip or/and twinning systems for orientations in the standard stereographic triangle of cubic crystal was investigated systematically. The Taylor factors and the anisotropy of yield strength for three important orientations [100], [110] and [111] in orientation space were analyzed. It is found that the yield strength asymmetry for the case of axisymmetric de- formation of tension and compression can be explained based on the microscopic theory of crystal plasticity. The concept of orientation factor for twinning ability was proposed and the deformation mechanism map in the orientation space was established for the case of axisymmetric deformation. The deformation texture formation and development of f.c.c. crystals with low stacking fault energy for axisymmetric tension can be explained qualita- tively on the basis of analyzed results.

关键词： twinning slip face-centered cubic crystals axisymmetric co-deformation Bishop-Hill maximum work principle yield strength anisotropy

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The mathematical model of wetting angle of heterogeneous nucleation

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Science China(Technological Sciences) 2004年第4期47卷 391-397页

作者： HUANG Cheng1, SONG Bo1, MAO Jinghong2 & ZHAO Pei3.1. school of Metallurgical and Ecological engineering, university of Science and Technology {3., {3. 100083. China 2. school of Material Science, university of Science and Technology {3., {3. 100083. China 3. Central Iron and Steel Research Institute, beijing 100081, China 1. school of Metallurgical and Ecological engineering University of Science and Technology Beijing 100083 Beijing China 2. school of Material Science University of Science and Technology Beijing 100083 Beijing China 3. Central Iron and Steel Research Institute 100081 Beijing China

The heterogeneous nucleation has been analyzed in terms of the thermodynamic theory, and the mathematical model of wetting angle of heterogeneous nucleation has been developed based on the dynamic requirements of hetero- and homogeneous nucleation. With the wetting angel model, the wetting angles of different catalysts in liquid iron have been calculated. The result shows that the wetting angle of most catalysts is smaller than 40, and the value of f() is far less than 1. The wetting angles of TiN, TiC and RE2O3.are smaller, while the wetting angle of MnO is bigger among the ordinary nucleation catalysts. The wetting angles calculated by this model are in agreement with the results of other research work.

关键词： heterogeneous nucleation, mathematical model, wetting angle, undercooling.

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PDMS prism-glass optical coupling for surface plasmon resonance sensors based on MEMS technology

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Science China(information Sciences) 2010年第10期53卷 2144-2158页

作者： GENG ZhaoXin 1,2 , LI Qing 3., WANG Wei 1 & LI ZhiHong 1 1 Institute of Microelectronics, Peking university, beijing 100871, China 2 school of information engineering, {3. university of China, beijing 100081, China 3.school of Sciences, Changchun university of Science and Technology, Changchun 13.000, China 1. Institute of Microelectronics Peking University Beijing 100871 China2. School of Information engineering Minzu University of China Beijing 100081 China3. School of Sciences Changchun University of Science and Technology Changchun 130000 China

A miniaturized surface plasmon resonance (SPR) chip has been developed for biomedical and chem-ical analysis with low cost and high performance. The techniques of bulk silicon micromachining and polymer replication were used to fabricate the Kretschmann SPR sensor composed of a Polydimethylsiloxane (PDMS) prism, a coupling glass and microchannels. The plasmon properties of thin metal films were investigated theoret-ically based on Fresnel analysis, with optical boundary conditions pertaining to the surface plasmon resonance at the gold/water and gold/air interfaces. The theoretical results show that difference in the refractive index (RI) between the PDMS prism and the coupling glass layer affect the precision of the SPR angle and the SPR curve. Meanwhile, the period of the interference fringe attaching on the SPR curve increases with an increase in wavelength and a decrease in the refractive index of the coupling glass layer. The gold thickness of 50 nm is required while employing a fixed incident wavelength of 650 nm, to achieve optimum SPR excitation conditions and the sensor sensitivity. The characteristics of this SPR sensor were evaluated in the angular interrogation mode of employing the incident wavelength of 650 nm in air and water media, respectively. The obtained SPR angles were approximately consistent with the theoretical ones.

关键词： surface plasmon resolance polymer microfluidic PDMS

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Digital close-range photogrammetric application to small-scale physical simulation experiment

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中国有色金属学会会刊：英文版 2011年第S3期21卷 681-685页

作者： LI Chun-yi1, CUI Xi-min2, YU Yi-ju3.1. school of Surveying and Landing information engineering, Henan Polytechnic {3., Jiaozuo 454003. China 2. College of Geoscience and Surveying engineering, China {3. of Mining and Technology, beijing 100083. China 3. Surveying and Mapping Press, beijing 100045, China [a] school of Surveying and Landing information engineering Henan Polytechnic University Jiaozuo 454003 China [b] College of Geoscience and Surveying engineering China University of Mining and Technology Beijing 100083 China [c] Surveying and Mapping Press Beijing 100045 China

In order to research the possibility of digital close-range photogrammetric surveying in small scale physical simulation experiment, physical model coinciding with engineering practice was constructed based on similar theory. The datum processing method and surveying precision of digital close-range photogrammetric were analyzed. And the function relationship between overburden subsidence factor qr and the ratio z/H of stratum horizon z and mining depth H was researched. The results show that surveying points position mean error along horizontal direction is ±0.13. mm and vertical direction is ±0.192 mm. Therefore, multi-taking station cross direction digital close-range photogrammetric can completely satisfy the precision need of physical simulation experiment. And the empirical formula can be utilized to represent evolution law of stratum subsidence factor.

关键词： close-range photogrammetric physical simulation light-rays adjustment surveying precision subsidence factor

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Study on NDVI-T_s space by combining LAI and evapotranspiration

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Science China Earth Sciences 2006年第7期49卷 747-754页

作者： HAN Lijuan1,2,3. WANG Pengxin4, YANG Hua1,2,3. LIU Shaomin1,2,3.& WANG Jindi1,2,3.1. Research Center for Remote Sensing and GIS, school of Geography, beijing Normal university, beijing 100875, China 2. State Key Laboratory of Remote Sensing Science, beijing 100875, China 3. beijing Key Laboratory for Remote Sensing of Environment and Digital Cities, beijing 100875, China 4. Department of information Management, College of information and Electronic engineering, China Agricultural university, beijing 100083. China 1. Research Center for Remote Sensing and GIS School of Geography Beijing Normal University Beijing 100875 China 2. State Key Laboratory of Remote Sensing Science Beijing 100875 China 3. beijing Key Laboratory for Remote Sensing of Environment and Digital Cities Beijing 100875 China 4. Department of information Management College of Information and Electronic Engineering China Agricultural University Beijing 100083 China

This paper focuses on interpreting the different spatial relationships between NDVI and Ts, a triangular or a trapezoid, and on analyzing transformation conditions, the physical and ecological meanings of the vegetation index-surface temperature space as well. Further, we use the Tempera-ture-Vegetation Dryness Index (TVDI) to explain the existent meaning of a triangular space after NDVI reaches its saturated state by employing the relationships between NDVI, LAI and evapotranspiration. The specific relations between NDVI and Ts are useful for describing, validating and updating land surface models.

关键词： NDVI, land surface temperature, evapotranspiration, leave area index.

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Study on Transformation of CaO-Al_2O_3.SiO_2-MgO System Inclusions in ZG06Cr13.i4Mo Stainless Steel

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Journal of Iron and Steel Research International 2011年第S2期18卷 341-346页

作者： LIU Jian-hui1,3. DONG Han1,3. ZHU Rong2, LI Shi-qi2 (1. Institute for Structural Materials,Central Iron and Steel Research Institute, beijing 100081,China 2. school of Metallurgical and Ecological engineering,{3. of Science and Technology beijing, beijing 100083.China 3. National engineering Research Center of Advanced Steel Technology, beijing 100081,China) Cent Iron & Steel Res Inst Inst Struct Mat Beijing 100081 Peoples R China Univ Sci & Technol beijing Sch Met & Ecol Engn Beijing 100083 Peoples R China Natl Engn Res Ctr Adv Steel Technol Beijing 100081 Peoples R China

This paper aims at generally studying on the inclusions of ZGG06Cr13.i4Mo ultra-low carbon stainless steel used for large scale hydraulic turbine sets. On the basis of analysis the industrial test samples, thermodynamic software FactSage is used to study inclusions transformation process in CaO-SiO2-Al2O3.MgO system while stainless steel is been smelting. The results illustrate the inclusions melting points and plasticity variation law. The reasonable inclusions plasticity controlling area is found out in low melting point. The melting point is up to 1280℃ While MgO weight concentration is 10% in CaO-SiO2-Al2O3.MgO system, SiO2, Al2O3.and CaO in inclusions are in weight concentration range of 50-70%, 10-20% and 10-40%, respectively. For purpose of gaining low melting point inclusions, silicon alumina radio in deoxidant should be controlled between 2-5 for ultra-low carbon stainless steel refining in industry.

关键词： ZG06Cr13.i4Mo stainless steel low melting point inclusion thermodynamic calculation

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Two possible mechanisms for vortex self-organization

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Science China Earth Sciences 2006年第2期49卷 202-211页

作者： LUO Zhexian2, ZHOU Xiuji1 & GAO Shouting3.1. Chinese Academy of Meteorological Sciences, beijing 100081, China 2. Department of Space information Science, Nanjing university of information Science and Technology, Nanjing 210044, China 3. Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 100029, China 2. Department of Environmental Science Nanjing University of Information Science and Technology Nanjing 210044 China 1. Chinese Academy of Meteorological Sciences Beijing 100081 China 3. Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The vortex self-organization is investigated in this paper by four groups of numerical experiments within the framework of quasi-geostrophic model, and based on the experimental results two types of possible mechanisms for vortex self-organization are suggested. The meso-scale to-pography may enable separated vortices to merge into a larger scale vortex; and the interaction of meso-γ and meso-β scale systems may make separated vortices to self organize a typhoon-like vor-tex circulation.

关键词： vortex, self-organization, meso-scale topography, interaction of different scales.

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Construction and application of formal ontology for mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 577-582页

作者： CHENG Gang 1, 2, ZHANG Yin-ling1, 2, WANG Fei 1 ,2, ZHANG Zhen-hui 3. GUO Yu-xiang1, 2 1. Key Laboratory of Mine Spatial information Technologies of State Bureau of Surveying and Mapping, Henan Polytechnic university, Jiaozuo 454003. China 2. school of Surveying and land information engineering, Henan Polytechnic university, Jiaozuo 454003. China 3. Qingdao Branch of Naval Aeronautical engineering Institute, Qingdao 266041, China Henan Polytech Univ Key Lab Mine Spatial Informat Technol State Bur Surveying & Mapping Jiaozuo 454003 Peoples R China Henan Polytech Univ Sch Surveying & Land Informat Engn Jiaozuo 454003 Peoples R China Naval Aeronaut Engn Inst Qingdao Branch Qingdao 266041 Peoples R China

Digital mine is the only way for the development of mining industry in China. Due to lack of appropriate standards and norms, and different awareness in the field of digital mine among academia and industry insiders, the meaning for digital mine is still unclear. Starting from the nature of mining and removing of views of specialized fields, this paper constructs formal ontology for digital mine and proposes the four levels for it. The ontology clarifies the concept world for digital mine, defines the meaning of concepts and relations clearly, provides a reference for the standard construction for digital mine and provides a unified semantic framework for the integration of heterogeneous mine data. Meanwhile, it can provide formal reasoning knowledge for expert system of digital mine and improve the intelligence and automation while the machine automatically interpreting and processing mine spatial data.

关键词： Digital mine formalization ontology concept world semantic share

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The regular representation and regular covariant representation of crossed products of Woronowicz C^(*)-algebras

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Science China Mathematics 2005年第9期48卷 1245-1259页

作者： ZHANG Xiaoxia~(1,2) & GUO Maozheng~(1,3. 1. school of Mathematical Sciences,Peking university,beijing 100871,China 2. Department of Mathematics,Yantai university,Yantai 264005,China 3. LMAM,Peking university,beijing 100871,China 1. school of Mathematical Sciences Peking University 100871 Beijing China 2. Department of Mathematics Yantai University 264005 Yantai China 3. LMAM Peking University 100871 Beijing China

In this paper,it is shown that the regular representation and regular covariant representation of the crossed products A×α G correspond to the twisted multiplicative unitary operators,where A is a Woronowicz C~*-algebra acted upon by a discrete group ***,it is also shown that the regular covariant C~*-algebra is the Woronowicz C~*-algebra which corresponds to a multiplicative ***,an explicit description of the multiplicative unitary operator for C(SU_q(2) )×α (?) is given in terms of those of the Woronowicz C~*-algebra C(SU_q(2) ) and the discrete group G.

关键词： multiplicative unitary operator, Woronowicz C*-algebra, crossed product.

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A formal model of fair exchange protocols

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Science in China(Series F) 2005年第4期48卷 499-512页

作者： QING Sihan1,2,3.& LI Gaicheng1,2,3.1. engineering Research Center for information Security Technology, Institute of Software, Chinese Aca- demy of Sciences, beijing 100080, China 2. beijing Zhongke Ansheng Corporation of information Technology, beijing 100080, China 3. Graduate school of the Chinese Academy of Sciences, beijing 10003., China 1. engineering Research Center for information Security Technology Institute of Software Chinese Academy of Sciences 100080 Beijing China 2. beijing Zhongke Ansheng Corporation of information Technology 100080 Beijing China 3. Graduate school of the Chinese Academy of Sciences 100039 Beijing China

Based on the study of existing fair exchange protocols, this paper sets up an accurate formal model by stepwise refinement. In the process of refinement an unreliable channel is employed to simulate an attack behavior. The model provides a novel formal definition of exchanged items, and presents the formal goals for fairness, accountability, etc., reflecting the inherent requirements for fair exchange protocols across-the-board. In order to check, prove, and design fair exchange protocols effectively and efficiently, the model puts forward a novel property of abuse-freeness which applies to all fair exchange protocols, gives a formal definition for trust strand of the third party, and presents general criteria of designing a secure and effective fair exchange protocol. Taking a typical fair exchange protocol as an example, this paper presents the analysis steps of fair exchange protocols appealing to our model. An unknown attack is uncovered. The analysis reveals the process of a complete attack, discovering deeper reasons for causing an attack. Finally, we modify the flawed protocol and the revised protocol ensures the desirable properties.

关键词： events local causal relation local temporal relation global relation exchanged item security goals.

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