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Quasi-secure quantum dialogue using single photons

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science china(Physics,Mechanics & Astronomy) 2007年第5期50卷 558-562页

作者： YANG YuGuang1,2.& WEN QiaoYan3. College of Computer science and Technology, beijing University of Technology, beijing 10002., china 2.state key laboratory of Information Security, Graduate University of the Chinese Academy of sciences, beijing 100049, china 3.School of science, beijing University of Posts and Telecommunications, beijing 100876, china College of Computer science Technology Beijing University of Technology Beijing 100022 China state key {2. of Information Security Graduate University of the Chinese Academy of Sciences Beijing 100049 China School of science Beijing University of Posts Telecommunications Beijing 100876 China

A quasi-secure quantum dialogue protocol using single photons was proposed. Different from the previous entanglement-based protocols, the present protocol uses batches of single photons which run back and forth between the two parties. A round run for each photon makes the two parties each obtain a classical bit of information. So the efficiency of information transmission can be increased. The present scheme is practical and well within the present-day technology.

关键词： quantum dialogue, single photon, quantum secure direct communication

Structure Evolution of Bulk Metallic Glass Zr_(52.5)Ni_(14.6)Al_10Cu_(17.9)Ti_5 during Annealing

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Journal of Materials science & Technology 2000年第4期16卷 357-361页

作者： Guo HE, Zan BIAN and Guoliang CHEN (state key {2. of Advanced Metals and Materials, University of {3. and Technology beijing,beijing 100083. china) state key {2. of Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

Bulk metallic glass Zr_52.5Ni_14.6Al_10Cu_17.9Ti_5 was prepared by melt injection casting method. Its glass transition and crystallization temperatures were determined by differential scanning calorimetry (DSC) to be 63. K and 710 K respectively. By analysis of X-ray diffractometry (XRD) and transmission electron microscopy (TEM ), the predominant crystallized phase of Zr_2.i0.67O0.3. distributed on glass state matrix was detected after annealing at 673.K for 600 s. The transformation to Zr_2.i_0.67O_0.3. and a small amount of ZrAl and Zr_2.u took place after annealing for 600 s at temperature from 703.K to 72. K. With increasing annealing temperature from 753.K to 82. K, the amounts of ZrAl and Zr_2.u increased, but the size of the crystals did not significantly change. The transformation to Zr_2.i_0.67O_0.3. is interface-controlled, but is diffusion-controlled to Zr_2.u and ZrAl. With increasing annealing temperature up to 2.0 K above T_x, the nanometer grains became very fine because of the increase of nucleation rate for Zr_2.u and ZrAl.

关键词： Structure Evolution of Bulk Metallic Glass Zr Ti5 during Annealing Al10Cu Ni Cu

Influence of Ru addition on microstructure and stress-rupture property of Ni-based single crystal superalloys

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Progress in Natural science:Materials International 2010年第1期20卷 61-69页

作者： Jing-yang CHEN~1,Qiang FENG~(1,2.,La-mei CAO~3.Zu-qing SUN~1 1.state key {2. for Advanced Metals and Materials,University of science and Technology beijing, beijing 100083.china 2.National Center for Materials Service Safety,University of science and Technology beijing,beijing 100083.china 3.National key {2. of science and Technology on Advanced High Temperature Structural Materials, beijing Institute of Aeronautical Materials,beijing 100095,china Univ Sci & Technol beijing State Key Lab Adv Met & Mat Beijing 100083 Peoples R China Univ Sci & Technol beijing Natl Ctr Mat Serv Safety Beijing 100083 Peoples R China beijing Inst Aeronaut Mat Natl Key Lab Sci & Technol Adv High Temp Struct M Beijing 100095 Peoples R China

The effects of Ru on the microstructure and stress-rupture property were investigated in two experimental Ni-based single crystal superalloys with and without Ru addition(5.1%,mass fraction).The results indicate that the morphology ofγ' precipitates in the dendrite core and interdendritic region are intermediate and nearly spherical,respectively,in the Ru-free alloy after being aged at 1100℃for 8 *** Re partitioning ratio increases due to Ru addition and Ru partitioned preferentially to theγphase in both dendrite core and interdendritic region of the Ru-containing alloy,which results in more negative lattice misfit and more cuboidalγ' ***,theγ' volume fraction increases while the precipitate size and y channel width decreases due to Ru addition in both dendrite core and interdendritic *** addition improves the stress-rupture life at 1100℃/140 MPa significantly due to higherγ' volume fraction,more negative lattice misfit and a well rafting structure as well as lessγchannel width.

关键词： Ni-based superalloys ruthenium elemental partitioning ratio lattice misfit γ’ morphology stress-rupture property

Conceptual design,data model and key techniques of“3. Assistant”

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中国有色金属学会会刊：英文版 2011年第S3期21卷 692-698页

作者： LI Qing-yuan1, ZHANG Xuan2. JIN Yang2. ZHOU Hui3. WANG Qian-jin3.WEI Zhan-yin1 1. key {3. of Geo-Informatics, Chinese Academy of Surveying and Mapping, {2. 10083., china 2. School of Geo-science and Surveying Engineering, china University of Mining and Technology, {2. 100083. china 3. School of Geomatics, Liaoning Technical University, Fuxin 12.000, china [a] key laboratory of Geo-Informatics Chinese Academy of Surveying and Mapping Beijing 100830 China [b] School of Geo-science and Surveying Engineering China University of Mining and Technology Beijing 100083 China [c] School of Geomatics Liaoning Technical University Fuxin 123000 China

Conceptual design, data model and key techniques of "Geo-engineer 3. assistant", an underground 3. GIS oriented to geology and mine application, were discussed. In particular, the importance of high-order smoothing triangular pieces to surface's fine expression in geological modeling was emphasized. The contour mode is the most favorite mode of the three modes about surface expression: DEM, TIN and contour. Topology in underground 3. modeling with CAGD was compared. From the view of boundary and coboundary, which is soul of IS 19107 (Geographic information spatial schema), 3. underground topology was re-examined.

关键词： 3. assistant true 3. GIS fine expression of surface contour mode 3. topology

A constitutive model of frozen soil with damage and numerical simulation for the coupled problem

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science china(Physics,Mechanics & Astronomy) 2010年第4期53卷 699-711页

作者： ZHU ZhiWu, NING JianGuo& MA Wei 1 School of Mechanics and Engineering, Southwest Jiaotong University, Chengdu 61003., china 2.state {2. laboratory of Explosion science and Technology, beijing Institute of Technology, beijing 100081, china 3.{2. laboratory of Frozen Soil Engineering, CAREERI, CAS, Lanzhou 73.000, china 1. School of Mechanics and Engineering Southwest Jiaotong University Chengdu 610031 China2. State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology Beijing 100081 China3. Key Laboratory of Frozen Soil Engineering CAREERI CAS Lanzhou 730000 China

Based on the microcosmic mechanics of composite materials, an elastic constitutive model for frozen soil with damage is presented. For frozen sandy soil with a range of ice contents and under a range of temperature conditions, quantitative results determined by this constitutive model agree with practically measured stress-strain curves. After numerically simulating the coupled water, temperature and stress fields of channel frozen and frozen roadbed using a self-developed finite-element routine, more accurate and practical calculation results for the temperature field coupled with stress, displacement and strain fields are obtained; the results match predictions and tests undertaken by earlier researchers. Our results support the reliability of our routine for calculating interdependent physical quantities of frozen soil and for describing the relationships between them. Our program can offer necessary constraints for engineering design and construction in permafrost regions.

关键词： frozen soil microcosmic mechanics roadbed coupling stress field

Nonlinear interactions between gravity waves and background winds

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Progress in Natural science:Materials International 2007年第6期17卷 639-644页

作者： Liu Xiao1,2.and Xu Jiyao1(1. state key {2. for Space Weather, Center for Space science and Applied Research, Chinese Academy of sciences, beijing 100080, china 2. Graduate University of Chinese Academy of sciences, beijing 10003., china) [a]state key {2. for Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China [b]Graduate University of Chinese Academy of sciences Beijing China

Using the nonlinear propagating gravity waves (GW) model in the two-dimensional compressible atmosphere and the linear GW theory, the process of GW propagation in different background winds, e.g. the direction of the background wind is opposite to (dead wind) or the same as (tail wind) the direction of the horizontal phase velocity of GW, is studied. The results show that the dead wind prolongs the vertical wavelength and accelerates GW propagation. Therefore, GW propagates up to a higher height becomes instable in a short time and eventually induces an inverse jet flow. Then, the vertical wavelength is becoming short due to the nonlinear interactions between GW and the inverse jet flow. The vertical wavelength and group velocity decrease after GW propagates into the tail wind. The initial instable time is delayed. Although most of GW is trapped in the instable region, some of GW propagates above the instable region. Compared with GW propagation in the tail wind, the nonlinear interactions between GW and the dead wind are also strong. In contrast, the linear GW theory predicts that GW can propagate freely in the dead wind. The vertical wavelength simulated by the nonlinear numerical model is different from that predicted by the linear theory greatly after GW propagates into the dead wind.

关键词： gravity waves background winds vertical group velocity vertical wavelength nonlinear interactions.

MEAM Potential with Angular Dependence for TiAl

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Rare Metals 2001年第1期20卷 13-17页

作者： Xiaodong Ni, Xitao Wang, Guoliang Chen (Physics Department, University of science and Technology beijing, beijing 100083.{3. state key laboratory for Advanced Metals and Materials, University of science and Technology beijing, beijing 100083.{3.) Univ Sci & Technol beijing Dept Phys Beijing 100083 Peoples R China Univ Sci & Technol beijing State Key Lab Adv Met & Mat Beijing 100083 Peoples R China

The modified embedded atom method (MEAM) is an empirical extension of the embedded atom method (EAM) that includes angular forces. By fitted to the lattice constants, the cohesive energy, the APE (anti-phase boundary) energy, and the vacancy formation energy of TiAl, an accurate MEAM potential is obtained for the TiAl system with L10 structure. The calculation results of the properties of TiAl are in good agreement with experiments and the results of first principle (F.P.) calculations.

关键词： embedded atom method TiAl alloy angular dependence potential intermetallics

Micro-alloying of yttrium in Zr-based bulk metallic glasses

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Progress in Natural science:Materials International 2011年第1期21卷 46-52页

作者： Wei-jie PENG,Yong ZHANG state key {2. for Advanced Metals and Materials, University of {3. and Technology beijing,beijing 100083.china state key {2. for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

The effect of yttrium addition on the glass-forming ability(GFA) and mechanical properties of the Zr-based (Zr0.52.Al0.1Ti0.05Cu0.179Ni0.146)100-xYxand(Zr0.55Al0.15Ni0.1Cu0.2.100-xYx(x=0,0.2.0.4 0.6,1,2. alloys was ***-alloying of 0.6%yttrium enhances the room temperature ductility as well as the GFA of the Zr-based *** mechanism of enhancing the GFA and room temperature ductility was *** is indicated that proper yttrium addition stabilizes the undercooled liquid by means of forming lots of ordered clusters,thus improving the GFA and the room temperature ductility.

关键词： micro-alloying glass-forming ability Zr-based alloys yttrium

Wide/narrow azimuth acquisition footprints and their effects on seismic imaging

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Petroleum science 2008年第4期5卷 308-313页

作者： Di Bangrang Xu Xiucang Wei Jianxin key laboratory of CNPC Geophysical Exploration China University of Petroleum Beijing 102249 China state key {2. of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China key laboratory of Earth Prospecting and Information Technology China University of Petroleum Beijing 102249 China

Acquisition footprint is a new concept to describe the seismic noise in three-dimensional seismic exploration and it is closely related to geometry and observation shuttering. At present, the study on acquisition footprints has become a hot spot. In partnership with the Dagang Oilfield, we used the channel sand body seismic physical model to study the characteristics of wide/narrow azimuth acquisition footprints and analyzed and compared the two types of footprints and their effects on target imaging. In addition, the footprints caused by data processing of the normal moveout offset （NMO） stretching aberration were discussed. These footprints are located only in the shallow or middle layer in the time slice, and possibly affect the imaging of shallow target layers, and have no influence on deep target imaging. Seismic physical modeling has its advantages in the study of acquisition footprints.

关键词： Wide/narrow azimuth geometry acquisition footprint stretching aberration time slice seismic imaging