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CORRELATION BETWEEN STRESS COMPONENTS AND STRESS CORROSION CRACKS IN BRASS Lecturer,department of materials Physics,University of {2. and Technology beijing,beijing 100083,China

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Acta Metallurgica Sinica(English Letters) 1992年第9期5卷 178-182页

作者： QIAO Lijie LIU Rui XIAO Jimei University of science and Technology beijing,beijing,China

The effects of stress components on nucleation sites and propagation directions of stress cor- rosion cracks in brass were investigated with specimens under mode Ⅱ and mode Ⅲ loadings. The results indicated that under mode Ⅱ loading,stress corrosion cracks nucleated on the site with maximum normal stress component and propagated along the plane perpendieular to the maximum normal stress,under mode Ⅲ loading,the stress corrosion crack was not evident on the 4.°plane due to the general corrosion in aqueous solution with high NH_4.H concentra- tion,while stress corroded in aqueous solution with low NH_4.H concentration, numerous cracks with spacings of 10—150μm were found on the 4.°plane with maximum normal stress and no stress corrosion cracks was observed on the plane with maximum shear stress.

关键词： stress corrosion cracking stress compoonent brass ammonia solution

Implementation of a multiple round quantum dense coding using nuclear magnetic resonance

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science China(Physics,Mechanics & Astronomy) 2005年第6期48卷 706-715页

作者： ZHANG Jingfu1, XIE Jingyi2. WANG Chuan1, DENG Zhiwei3, LU Zhiheng4. & LONG Guilu1,5 1. Key Laboratory For Quantum Information and Measurements of MOE, department of Physics, Tsinghua University, beijing 100084.China 2. {2., beijing Normal University,{4., China 3. Testing and Analytical Center, beijing Normal University,{4.,China 4. department of Physics, beijing Normal University,{4., China 5. Key Laboratory For atomic and Molecular Nanosciences, Tsinghua University, beijing 100084.China 1. Key Laboratory For Quantum Information and Measurements of MOE Department of Physics Tsinghua University 100084 Beijing China 2. department of materials science and engineering Beijing Normal University 100875 Beijing China 3. Testing and Analytical Center Beijing Normal University 100875 Beijing China 4. department of Physics Beijing Normal University 100875 Beijing China 5. Key Laboratory For Atomic and Molecular Nanosciences Tsinghua University 100084 Beijing China

A multiple round quantum dense coding scheme based on the quantum phase estimation algorithm is proposed and implemented in a three qubit nuclear magnetic resonance (NMR) quantum computer. Using an m + 1 qubit system, Bob can transmit one of 2.+1 messages to Alice, through manipulating only one qubit and exchanging it between Alice and Bob for m rounds. The information capacity is enhanced to m + 1 bits as compared to m bits in a classical scheme. The scheme has been demonstrated in NMR system, and the experimental results show a good agreement between theory and experiment.

关键词： quantum dense coding, multiple round, nuclear magnetic resorance

Exotic structure of the third excited state in^(2.)Na

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Chinese science Bulletin 2005年第23期50卷 2677-2680页

作者： LI Xihan1,2.3, LIANG Yujie1,2.3, DENG Fuguo1,2.3, LIU Zuhua1,4.& ZHOU Hongyu1,2.3 1. Key Laboratory of Beam Technology and Material Modification of Minister of Education, {4. Normal University, beijing 100875, China 2. Institute of Low Energy Nuclear Physics, and {2. of Material science and {4., {4. Normal University, beijing 100875, China 3. {4. Radiation Center, beijing 100875, China 4. China Institute of Atomic Energy, {4. 102.13, China Key Laboratory of Beam Technology and Material Modification of Minister of Education Beijing Normal University Beijing 100875 China Institute of Low Energy Nuclear Physics and Department of Material Science and Engineering Beijing Normal University Beijing 100875 China beijing Radiation Center Beijing 100875 China China Institute of Atomic Energy Beijing 102413 China

The probability of the last proton being out of the binding potential, P and the root-mean-square (rms) ra- dius (1/2. of the third excited state in 2.Na are calcu- lated by means of asymptotic normalization coefficie... 详细信息

The probability of the last proton being out of the binding potential, P and the root-mean-square (rms) ra- dius (2.1/2. of the third excited state in 2.Na are calcu- lated by means of asymptotic normalization coefficient (ANC) method with the experimental date existing. The results are P=54.73% and 2.1/2.5.2. fm respectively. The P value and the contribution of the asymptotic part to the 2.1/2.are compared with those of several other low energy states in 2.Na. It is found that the valence particle in the third excited state has an obvious larger P than those of other states. The density distribution of the valence proton in this state is also compared with the nucleons in the nuclear core 2.Ne, and a far extended tail can be seen clearly. These results show that the third ex- cited state in 2.Na is a proton halo state.

关键词：钠第三激发态外部结构有效半径密度分布渐近标准化系数

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, {4. Normal University, beijing 100875, China 2. State Key Laboratory of Remote Sensing {2., beijing 100875, China 3. {4. 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, {4. 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.

A MASSIVE TRANSFORMATION MECHANISM IN Ti-4.Al ALLOY

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中国有色金属学会会刊：英文版 1996年第3期6卷 68-73页

作者： Wen Cuie Lin Jianguo Chen Changqi(department of materials science and engineering, beijing University of Aeronautics and Astronautics, beijing 100083) beijing UNIV AERONAUT & ASTRONAUT DEPT MAT SCI & ENGN BEIJING 100083 PEOPLES R CHINA

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关键词： TiAl alloy massive transformation diffusion controlled ledge growth mechanism

Dense coding scheme using superpositions of Bell-states and its NMR implementation

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science China(Physics,Mechanics & Astronomy) 2005年第1期48卷 57-67页

作者： ZHANG Jingfu, XIE Jingyi, DENG Zhiwei & LU Zhiheng Key Laboratory for Quantum Information and Measurements, department of Physics, Tsinghua University, beijing 100084. China Center for Quantum Information, Tsinghua University, beijing 100084. China department of materials science and engineering, beijing Normal University, beijing 100875, China Testing and Analytical Center, beijing Normal University, beijing 100875, China department of Physics, beijing Normal University, beijing 100875, China 1. Key Laboratory for Quantum Information and Measurements Department of Physics Tsinghua University 100084 Beijing China 2. Center for Quantum Information Tsinghua University 100084 Beijing China 3. department of materials science and engineering Beijing Normal University 100875 Beijing China 4. Testing and Analytical Center Beijing Normal University 100875 Beijing China 5. department of Physics Beijing Normal University 100875 Beijing China

Dense coding using superpositions of Bell-states is proposed. The generalized Grover's algorithm is used to prepare the initial entangled states, and the reverse process of the quantum algorithm is used to determine the entangled state in the decoding measurement. Compared with the previous schemes, the superpositions of two Bell-states are exploited. Our scheme is demonstrated using a nuclear magnetic resonance (NMR)quantum computer. The corresponding manipulations are obtained. Experimental results show a good agreement between theory and experiment. We also generalize the scheme to transmit eight messages by introducing an additional two-state system.

关键词： dense coding, superpositions of Bell-states, generalized Grover's algorithm, nuclear magnetic res-onance, quantum computer.

ENERGY FLOWS IN COMPLEX ECOLOGICAL SYSTEMS:A REVIEW

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Journal of Systems science & Complexity 2009年第3期22卷 345-359页

作者： Jiang ZHANG department of Systems science,School of Management,{2. Normal University,{2. {4.,China. department of Systems science School of Management Beijing Normal University Beijing 100875 China

Energy flow drives the complex systems to *** allometric scaling as the universalenergy flow pattern has been found in different scales of ecological *** reflects the generalpower law relationship between flow and *** underlying mechanisms of energy flow patterns areexplained as the branching transportation networks which can be regarded as the result of systematicoptimization of a biological target under *** flows in the ecological system may bemodelled by the food web model and population dynamics on the *** paper reviews thelatest progress on the energy flow patterns,explanatory models for the allometric scaling and modellingapproach of flow and network evolution dynamics in ***,the possibility of generalizingthese flow patterns,modelling approaches to other complex systems is discussed.

关键词： Allometric scaling energy flow flows in complex systems food web.

Effects of surface modification on thermal cycling lifetime of thermal barrier coatings with HVOF NiCrAlY bond coat

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Progress in Natural science:materials International 2012年第3期22卷 237-243页

作者： Liyong Ni, Chungen Zhou department of materials science and engineering, beijing University of Aeronautics and Astronautics, beijing 100191, China department of materials science and engineering Beijing University of Aeronautics and Astronautics Beijing 100191 China

NiCrAlY bond coat was prepared by HVOF (high-velocity oxygen fuel) spray on nickel-based superalloy. Surface treatments like grit-blasting, shot-peening and vacuum treatment methods were carried out in order to study the effects of surface modification on thermal cycling lifetime of TBCs. The surface-modified TBCs exhibited better thermal shock resistance. Failure of TBCs with the as-sprayed bond coat occurred within the top coat and at the interface between spinels and the top coat, while that of after shot-peening, grit-blasting and vacuum treatment occurred mainly within the top coat. TGO (thermally grown oxide) formed on as-sprayed bond coat was composed of a Ni(Al,Cr)2.4.spinels outer layer and a Al2.3 inner layer. But, a continuous and uniform Al2.3 formed after surface modification. Formation of the mixed oxides (spinels) on the as-sprayed bond coat accelerated the failure of TBCs.

关键词： Thermal barrier coatings NiCrAlY HVOF Thermally grown oxide (TGO)

Anomalous magnetotransport in LaMn_(1-x)Te_xO_3

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science China(Physics,Mechanics & Astronomy) 2009年第7期52卷 987-992页

作者： TAN GuoTai1,2. CHEN ZhengHao3 & ZHANG XiaoZhong4.5 1 Key Laboratory of Beam Technology & materials Modification of the Ministry of Education, Institute of Low Energy Nuclear Physics, beijing Normal University,{2., China 2.beijing Radiation Center,{2., China 3 Laboratory of Optical Physics, Institute of Physics, Chinese Academy of sciences, beijing 100080, China 4.Key Laboratory of Advanced materials of the Ministry of Education, department of materials science and engineering, Tsinghua University, beijing 100084. China 5 beijing National Center for Electron Microscopy, Tsinghua University, beijing 100084. China 1. Key Laboratory of Beam Technology & materials Modification of the Ministry of Education Institute of Low Energy Nuclear Physics Beijing Normal University Beijing 100875 China 2. beijing Radiation Center Beijing 100875 China 3. Laboratory of Optical Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China 4. Key Laboratory of Advanced materials of the Ministry of Education Department of Materials Science and Engineering Tsinghua University Beijing 100084 China 5. beijing National Center for Electron Microscopy Tsinghua University Beijing 100084 China

The LaMn1-xTexO3+δ (x=0.1, 0.2. 0.3) were synthesized using solid-state reaction method for the first time. X-ray photoemission spectrum (XPS) shows that in the samples the Te ions have a valence of Te4., and Mn3+ ions are partly converted into Mn2. and Mn4. due to the excess oxygen and Te doping. The magnetotransport associated with Mn2., Mn3+ and Mn4. was investigated. The experimental results show that the samples are insulator at 0 T when the amount of Mn3+ is much larger or less than the sum of Mn2. and Mn4.; by contrast, the samples display metal to insulator transition with increasing temperature when the amount of Mn3+ is close to the sum of Mn2. and Mn4.. These anomalous magnetotransport behaviors were analyzed in the frame of the double-exchange (DE) mechanism.

关键词： colossal magnetoresistance La-Te-Mn-O magnetotransport