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Study on dynamic fracture behavior of TA15ELI alloy under mode-Ⅱ loading by caustics method

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Rare Metals 2010年第4期29卷 361-365页

作者： LIU Rui,HUI Songxiao,YE Wenjun,MI Xujun,XIONG Baiqing,and YOU Zhenping State Key Laboratory for Fabrication & Processing of Nonferrous Metals,General Research institute for Nonferrous Metals,beijing 100088,{2. State Key Laboratory for Fabrication & Processing of Nonferrous Metals General Research Institute for Nonferrous Metals Beijing China

The dynamic fracture behavior of TA 15ELI alloy with lath-like microstructure was studied by caustics method. Specimens with double-side pre-notch were tested under the plane-stress condition at mode-II loading with a drop hammer system. Caustics information recorded in films illustrated the histories of both crack length and stress intensity factor. The dynamic fracture toughness and crack growth velocity of TA15ELI with lath-like microstructure were determined to be 2.9 MPa.m1/2.and 32.6 m/s, respectively. SEM fractograph analysis showed a mixed feature of mainly plastic mode for TA 15ELI alloy in dynamic mode-II fracture. Shear localization was observed in the vicinity of the crack initiation area.

关键词： titanium alloy dynamic fracture caustics method fracture toughness crack growth

Research on arc erosion of silver-based alloy contact materials under low voltage,resistive load and small current at 400 Hz and 50 Hz

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Journal of Pharmaceutical Analysis 2009年第3期21卷 149-154页

作者： Jing Li1,2.Zhi-ying Ma11. School of Electrical Engineering,Xi’an Jiaotong University,Xi’an 710049 2. School of Electrical Information,Hunan institute of Engineering,Xiangtan 411101,china. School of Electrical Engineering Xi'an Jiaotong University Xi'an 710049 China School of Electrical Information Hunan Institute of Engineering Xiangtan 411101 China

By using a self-developed IF power and a ASTM contact material experimental system of small-capacity and variable frequency,the value of arcing characteristics and the welding force of the silver-based contact material are acquired under low voltage,resistive load and small current at 400 Hz and 50 Hz. By means of an electricity-ray analytical balance,SEM and EDAX,the weighing values of the contact materials and the changes of AgCdO,AgNi,AgC and AgW contact material surface profile and micro-area constituent are obtained and analyzed. The arc erosion causes of silver-based alloy contact materials at 400 Hz and 50 Hz are also discussed.

关键词： silver-based alloy low voltage 400 Hz 50 Hz contact material arc erosion

The structural model of P_(680)

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Chinese Science Bulletin 1999年第9期44卷 862-863页

作者： ZHANG Chunxi , ZHANG Xiaodong , LI Liangbi , ZHANG Qiyuan , ZHANG Xingkang and KUANG TingyunPhotosynthesis Research Center and Laboratory of Photosynthesis Basic Research , institute of Botany , Chinese Academy of Sciences , beijing 100093,{2. State Key Laboratory for Structural Chemistry of Unstable and Stable Species , institute of Chemistry, Chinese Academy of Sciences , beijing 100080,{2. Photosynthesis Research Center and Laboratory of Photosynthesis Hasic Research Institute of Botany Chinese Academy of Sciences Beijing China State Key Laboratory for Structural Chemistry of Unstable and Stuble Species. institute of Chemistry Chinese Academy of Sciences Beijing China

INVESTIGATION on photosystem Ⅱ （PS Ⅱ ） of high plants is one of the most important aspects in photosynthesis research. P680 is the primary electron donor in reaction center of PS Ⅱ , which is a crucial component for sun-light conversion and water split in PS Ⅱ. So study on its structure and function is very important. So far, a few structural models of P（680） have been proposed. Typical models are monomolecular model and bimolecular model. There are two types of bimolecular model: bimolecular parallel model and bimolecular angular model. (Note: There is a kind of multiple model. Because it can be obtained from the organization of two bimolecular models, this model is considered as the same sort of bi-

关键词： The structural model of P

Fertility analysis of the Arabidopsis transformed with antisense rice osRACD gene

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Progress in Natural Science:Materials International 2003年第6期 26-30页

作者： YE Jianrong, HUANG Meijuan and WU Naihu (1. institute of Genetics and Developmental Biology, Chinese Academy of Sciences, beijing 100080,{2. 2. College of Life Science, Peking University, beijing 100871,{2.) institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing 100080 China College of Life Science Peking University Beijing 100871 China

The full length osRACD cDNA sequence was subcloned into the pBI12. plasmid in the antisense orientation under the control of the CaMV35S promoter to construct the expression vector pBID, and the constructs were introduced into Arabidopsis plants by using the vacuum infiltration method. The siliques of the transformants stopped growing after anthesis, and they turned yellow or died later; and the siliques from the control plants transformed by the pBI continued growing after anthesis and matured normally. In -vitro pollen germination demonstrated that the growth and elongation process of the pollens of the transgenic plants was inhibited, the pollen tubes were shorter and slightly fatter than the tubes of the control plants, which grew normally with long cyclindrical tubes. The above results suggest the function of osRACD gene involved in regulation of the growth and elongation process of pollen tube, its encoding protein may be one of the important factors in regulation of fertility transition of the ph

关键词： rice osRACD gene Arabidopsis transgene.

CHANNEL SHRINKAGE AND ITS INSTABILITY IN THE LOWER YELLOW RIVER

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International Journal of Sediment Research 2006年第1期 13-23页

作者： Jianguo CHEN2. Wenhao ZHOU3 and Anjun DENG4 2.Prof., Deputy Director, Department of Sedimentation, china institute of Water Resources and Hydropower Research, {2., china, 3 Prof., china institute of Water Resources and Hydropower Research, {2., china, 4 Engineer, china institute of Water Resources and Hydropower Research, {2., china,

From the mid 1980s through the late 1990s, the channel of the lower Yellow River experienced serious shrinkage, which has decreased the flood conveyance of the channel and the sediment carrying capacity of the flow, raised the water levels of floods, and, thus, severely threatened the safety of flood control along the river. The completion of Xiaolangdi Dam in 1999 could help mitigate the channel shrinkage problem, but the situation has not changed yet. This paper analyses the characteristics, mechanisms, and conditions resulting in channel shrinkage, points out channel instabilities, and puts forward approaches of channel rehabilitation.

关键词： Channel shrinkage Main channel Hydrological condition Regulation of water and sediment

Competitive and cooperative adsorption of arsenate and citrate on goethite

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Journal of Environmental Sciences 2009年第1期21卷 106-112页

作者： SHI Rong,JIA Yongfeng,WANG Chengzhi institute of Applied Ecology,Chinese Academy of Sciences,Shenyang 110016,china institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China

The fate of arsenic in natural environments is influenced by adsorption onto metal （hydr）oxides. The extent of arsenic adsorption is strongly affected by coexisting dissolved natural organic acids. Recently, some studies reported that there existed competitive adsorption between arsenate and citrate on goethite. Humic acid is known to interact strongly with arsenate by forming complexes in aqueous solution, hence it is necessary to undertake a comprehensive study of the adsorption of arsenate/citrate onto goethite in the presence of one another. The results showed that at the arsenate concentrations used in this study （0.006-0.2. mmol/L）, citrate decreased arsenate adsorption at acidic pH but no effect was observed at alkaline pH. In comparison, citrate adsorption was inhibited at acidic pH, but enhanced at alkaline pH by arsenate. This was probably due to the formation of complex between arsenate and citrate like the case of arsenate with humic acid. These results implied that the mechanism of the adsorption of arsenate and citrate onto goethite in the presence of one another involved not only competition for binding sites, but the cooperation between the two species at the watergoethite interface as well.

关键词： adsorption arsenate citrate goethite

ROBUST CONSENSUS AND SOFT CONTROL OF MULTI-AGENT SYSTEMS WITH NOISES

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Journal of Systems Science & Complexity 2008年第3期21卷 406-415页

作者： Lin WANG Lei GUO institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China

这篇论文与围住的骚乱并且与指导信息流动为多代理人系统的一个基本的班考虑柔韧的一致的问题。柔韧的一致上的一个必要、足够的条件首先被介绍，它然后在噪音环境被用于分析，控制和决策问题。特别地，作者显示出一种软控制技术怎么将... 详细信息

这篇论文与围住的骚乱并且与指导信息流动为多代理人系统的一个基本的班考虑柔韧的一致的问题。柔韧的一致上的一个必要、足够的条件首先被介绍，它然后在噪音环境被用于分析，控制和决策问题。特别地，作者显示出一种软控制技术怎么将同步没有改变相互作用的存在本地规则，并且没有在系统轨道上假定任何种连接条件的一组自治活动代理人。

关键词：时变系统多Agent系统鲁棒一致性软控制有向图

SUBSTITUTION BEHAVIOR OF ALLOYING ELEMENTS IN INTERMETALLIC COMPOUND，TiAl

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Acta Metallurgica Sinica(English Letters) 1995年第Z1期8卷 609-613页

作者： XU Dongsheng SONG Yan LI Dong HU Zhuangqi(institute of Metal Research, Chinese Academy of Sciences, Shenyang, china)(Northeastern University, Shenyang, china) Inst of Metal Research Chinese Acad of Sciences Shenyang China

A method based on electronic structure calculation is proposed to predict the substitution behavior of elements in ordered intermetallics. The electronic structure of 2. alloying elements in TiAl is calculated using the DV-Xα cluster method The bond orders between alloying elements and surrounding atoms, Bo_Ti,Bo_Al, are used as parameters. Two lines on the Bo_Ti-Bo_Al diagram separate the elements into three groups. The elements located outside of the two lines substitute either Ti or Al atom regardless of the composition of TiAl. The substitution behavior of elements between the two lines will be affected by the Ti/Al ratio and the amount of alloying elements added Substituting sequence in multi-element alloy is discussed The prediction based on this method agrees well with the experimental results.

关键词： substitution behavior site occupancy intermetallic compound, TiAl electronic structure

A preliminary analysis on lithospheric thickness and crustal ages in central basin of South china Sea

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Acta Oceanologica Sinica 1997年第1期16卷 85-107页

作者： Chen Xue and Lin Jinfeng South china Sea institute of Oceanology, the Chinese Academy of Sciences, Guangzhou 510301, china South china Sea institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China

The models about lithospheric thickness and thermal conduction inside the lithosphere and the top layer of the asthenosphere have been proposed in this study for four type regions: the midoceanic ridge, the extinct spreading ridge, the lithospheric fault fissure and the mouth of the extinct submarine volcanoes which are in deep sea bottom. The solutions of the models are found to be the same. The formulas of temperature distribution inside the lithosphere and the top layer of the asthenosphere, the lithospheric thicknesses to the heat flow and the crustal ages to the heat flow are obtained. The crustal ages and the lithospheric thicknesses of the central basin are calculated. And they are used to draw the lithospheric thicknesses and crustal ages maps of the central basin (in this paper both the central basin and the basin are the central basin of the South china Sea). According to their characteristics, the central basin is divided into three regions. The lithospheric thicknesses, crustal ages and heat flow distribution characteristics are discussed respectively. The formation and evolution of the South china Sea are analysed and it is thought that the South china Sea has undergone three episode-seafloor spreadings.

关键词： Thermal conduction equation lithospheric thickness crustal age evolution