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Corrosion behavior of Mg-Y alloy in NaCl aqueous solution

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Progress in Natural Science:Materials International 2012年第2期22卷 169-174页

作者： Xin Zhang a,b,c,Kui Zhang a,Xia Deng a,Hongwei Li b,c,Yongjun Li a,Minglong Ma a,Ning Li b,c,Yanlong Wang b,c a State Key Laboratory for Fabrication and Processing of Nonferrous Metals,beijing General research institute for Nonferrous Metals,beijing 100088,china b beijing Engineering research Center for Advanced Manufacturing and Evaluation of special Vehicle Parts,beijing 100072,china c Center of technology,beijing North Vehicle Group Corporation,beijing 100072,china [a] State Key Laboratory for Fabrication and Processing of Nonferrous Metals Beijing General Research Institute for Nonferrous Metals Beijing 100088 China [b] beijing Engineering research Center for Advanced Manufacturing and Evaluation of special Vehicle Parts Beijing 100072 China [c] Center of technology Beijing North Vehicle Group Corporation Beijing 100072 China

The corrosion behavior of Mg-(0.25,2.5,5,8 and 15)Y alloys in 3.5wt.%NaCl aqueous solution was *** was found that the degree of corrosion deterioration increased with increasing immersion time up to 2 *** modes for the alloys with low and high content of Y element were general corrosion and pitting corrosion,respectively,and the threshold content for the corrosion mode change was 2.5%for the tested *** experimental results showed that the addition of Y refined the grain of the alloy,and the distribution,i.e.,continuous or not,of the Mg24Y5 phases had great effect on the corrosion rate and corrosion mode.

关键词： Mg-Y Corrosion Microstructure

Deformation-induced α_2/γ Interfaces in a Hot-deformed Ti-45Al-10Nb Alloy

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Journal of Materials Science & technology 1998年第2期14卷 132-138页

作者： Jinguo WANG Lichun ZHANG and Guoliang CHEN (State Key Lab. for Advanced Metals and Materials, University of Science and technology beijing, beijing 100083, china )Henqiang YE(Lab. of Atomic Imaging of Solids, institute of Metal research, Chinese Academy State Key Lab. for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China Lab. of Atomic Imaging of Solids Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

The structure change of α2/γ interface in a Ti-45Al-10Nb alloy induced by hot deformation was investigated by conventional and high-resolution transmission eIectron microscopy. Two types of hot deformation induced special α2/γ intedeces, coherent intedeces with high density of ledges and semi-coherent α2/γ intedeces were found to be due to the absorption of mobile dislocations into the α2/γ inteface. For the misoriented semi-coherent α2/γ interfaces, the densities of dislocation ledges increase with the misoriented angle between (111)γ and (0001)α2 planes, and 1/3[111] Frank partial dislocations were involved in the dislocation ledges. Formation mechanism of these deformation-induced α2/γ interfaces was discussed to be related to the role of α2/γ interface5 adjusting the deformation as a dislocation sink absorbing the slipping dislocations in the γ phase

关键词： Al Ti Interfaces in a Hot-deformed Ti-45Al-10Nb Alloy Deformation-induced

The principle of relativity, kinematics and algebraic relations

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Science china(Physics,Mechanics & Astronomy) 2010年第4期53卷 591-597页

作者： GUO HanYing1, HUANG ChaoGuang2,3, WU HongTu4 & ZHOU Bin5 1institute of Theoretical Physics, Chinese Academy of Sciences, beijing 100190, china 2institute of High Energy Physics, Chinese Academy of Sciences, beijing 100049, china 3Theoretical Physics Center for Science Facilities, Chinese Academy of Sciences, beijing 100049, china 4Department of Mathematics, Capital Normal University, beijing 100048, china 5Department of Physics, beijing Normal University, beijing 100875, china 1. institute of Theoretical Physics Chinese Academy of Sciences Beijing 100190 China2. Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China3. Theoretical Physics Center for Science Facilities Chinese Academy of Sciences Beijing 100049 China4. Department of Mathematics Capital Normal University Beijing 100048 China5. Department of Physics Beijing Normal University Beijing 100875 China

Based on the relativistic principle and the postulate of universal invariant constants (c, l), all kinematic symmetries can be set up as the subsets of the Umov-Weyl-Fock-Hua transformations for the inertial motions. ... 详细信息

关键词： principle of relativity with (c l) Umov-Weyl-Fock-Hua transformations kinematics special relativity triple

Nonholonomic mapping theory of autoparallel motions in Riemann-Cartan space

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Science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1707-1715页

作者： GUO YongXin1,LIU Chang2,WANG Yong3,LIU ShiXing1 & CHANG Peng2 1 College of Physics,Liaoning University,Shenyang 110036,china 2 School of Aerospace Engineering,beijing institute of technology,beijing 110081,china 3 School of Basic Medical Science,Guangdong Medical College,Dongguan 523808,china 1. College of Physics Liaoning University Shenyang 110036 China2. School of Aerospace Engineering Beijing Institute of Technology Beijing 110081 China3. School of Basic Medical Science Guangdong Medical College Dongguan 523808 China

The method of nonholonomic mapping is utilized to construct a Riemann-Cartan space embedded into a known Riemann-Cartan space,which includes two special cases that a Weitzenbck space and a Riemann-Cartan space are respectively embedded into a Euclidean space and a Riemann *** means of this mapping theory,the nonholonomic corresponding relation between the autoparallels of two Riemman-Cartan spaces is *** particular,an autoparallel in a Riemann-Cartan space can be mapped into a geodesic line in a Riemann space and an autoparallel in Weitzenbck space be mapped into a geodesic line in Euclidean *** on the Lagrange-d'Alembert principle,the equations of motion for dynamical systems in Riemman-Cartan space should be autoparallel equations of the *** applications,the problem of autoparallel motion of spinless particles,Chaplygin's nonholonomic systems and a rigid body rotating with a fixed point are investigated in space with torsion.

关键词： nonholonomic mapping Riemann-Cartan space connection torsion autoparallel

Pairwise entanglement and local polarization of Heisenberg model

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Science china(Physics,Mechanics & Astronomy) 2008年第10期51卷 1515-1522页

作者： XI XiaoQiang1,2, ZHANG Tao3, YUE RuiHong3,4 & LIU WuMing2 1 Department of Applied Mathematics and Physics, Xi’an institute of Post and Telecommunications, Xi’an 710061, china 2 beijing National Laboratory for Condensed Matter Physics, institute of Physics, Chinese Academy of Sciences, beijing 100080, china 3 institute of Modern Physics, Northwest University, Xi’an 710069, china 4 Department of Physics, Ningbo University, Ningbo 315211, china Department of Applied Mathematics and Physics Xi’an Institute of Post and Telecommunications Xi’an 710061 China beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China institute of Modern Physics Northwest University Xi’an 710069 China Department of Physics Ningbo University Ningbo 315211 China

The characteristics of pairwise entanglement and local polarization (LP) are dis-cussed by studying the ground state (states) of the Heisenberg XX model. The re-sults show that: the ground state (states) is (are) composed of the micro states with the minimal polarization (0 for even qubit and 1/2 for odd qubit); LP and the prob-ability of the micro state have an intimate relation, i.e. the stronger the LP, the smaller the probability, and the same LP corresponds to the same probability; the pairwise entanglement of the ground state is the biggest in all eigenvectors. It is found that the pairwise entanglement is decreased by the state degeneracy and the system size. The concurrence approaches a fixed value of about 0.3412 (for odd-qubit chain) or 0.3491 (for even-qubit chain) if the qubit number is large enough.

关键词： Heisenberg XX model local polarization pairwise entanglement

The driving force for development of IC and systemin future: Reducing the power consumption andimproving the ratio of performance to powerconsumption

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Science china(Information Sciences) 2011年第5期54卷 915-935页

作者： WANG YangYuan institute of Microelectronics, Peking University, beijing 100871, china 1. institute of Microelectronics Peking University Beijing 100871 China

With the development of information technology, integrated circuits (IC) and system which target high performance and low power consumption have widely penetrated to all the aspects of national economy, national defense construction and people’s life. With the continuous increase in IC integration density, the power consumption is becoming the limiting factor. It turns out that the driving force of the future IC and system development is the reduction of the power consumption and improvement of the performance/power ratio. The Moore’s Law is inherently the law for the technology and economic development, and has served as the guideline of the IC development for half a century. However, with the scaling down of IC feature size and the corresponding increased integration density, it is progressively approaching the physical limitation. Moore’s Law will gradually complete its historic mission and it will be replaced by a law of reducing the power consumption while ensuring the performance requirements for IC, SoC and SiP performance, law of improving the performance/power ratio. This paper will discuss the related research topics on Green micro/nanoelectronics, including low-power design, novel low-power devices, manufacturing processes for low power applications and related micro/nano electromechanical systems.

关键词： power consumption IC technology

Threat and management strategies of potentially invasive insects in china

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Science china(Life Sciences) 2009年第10期52卷 903-910页

作者： ZHANG RunZhi1, ZHANG YaPing2 & JIANG YouXu3 1 State Key Laboratory of Integrated Management of Pest Insects and Rodents in Agriculture, institute of Zoology, Chinese Academy of Sciences, beijing 100101, china 2 Kunming institute of Zoology, Chinese Academy of Sciences, Yunnan, 650223, china 3 The research institute of Forest Ecology, Environment and Protection, The Chinese Academy of Forestry, beijing 100091, china State Key Laboratory of Integrated Management of Pest Insects and Rodents in Agriculture Institute of Zoology Chinese Academy of Sciences Beijing 100101 China Kunming institute of Zoology Chinese Academy of Sciences Yunnan 650223 China The research institute of Forest Ecology Environment and Protection The Chinese Academy of Forestry Beijing 100091 China

The Global Invasive Species Database, GISD, comprises 27 species of the most significant invasive alien insects in the world (through November, 2005), 6 of which are originally native to china, 11 are established in china, and 10 have a potential invasion threat to china. This paper discusses these species in terms of distribution, harmfulness and dispersal ways, and finds that: (i) Information re-garding invasive insects in the GISD remains inadequate. Such harmful invasive species as Opogona sacchari (Bojer), Oracella acuta (Lobdell), and Dendroctonus valens LeConte are not included. (ii) Ten species of invasive insects, particularly Lasius neglectus Van Loon and Linepithema humile (Mayr) which become established in areas near china, have the potential to become established in china. (iii) special attention should be paid to species from Asia and the Americas because of their greater likeli-hood of becoming established in china. Finally, some management strategies including legislation, quarantine, early warning, prevention and control are suggested.

关键词： biological invasions invasive species insect china

Seismic multi-arch structures in East china

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Science china Earth Sciences 2006年第2期49卷 133-146页

作者： YANG Wencai1 & CHEN Zhide2 1.institute of Geology, Chinese Academy of Geological Sciences, beijing 100037, china 2.Daqing institute of Petroleum Exploration and Production, Daqing 163712, china 1. institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China 2. Daqing institute of Petroleum Exploration and Production Daqing 163712 China

In previous papers (Wencai, 2002, 2003), the author has analyzed the deep seismic reflection profiles along some of the Mesozoic plutons in East china, and has pointed out that the crustal structures around these intrusions usually correlate with a special seismic fabric called the seismic multi-arch structure. This paper will continue to show main characteristics of the seismic multi-arch structures and discuss their relationship with mantle-origin magmatism and the lithospheric thinning process. Calibration of seismic reflectors in Chinese continental drilling sites shows that small-scale arch-like reflectors can be generated by fractured eclogites or other plutons, they do not belong to the multi-arch structure specially discussed in the paper. The multi-arch structure is char-acterized by several arch-like reflectors distributed in both the upper and lower crust with granitoid plutons or stocks exposed on the surface, which do not have obvious negative Europium anomalies. Based on the distribution pattern of arch reflectors, the multi-arch magmatic structures can be divided into three main types, namely the simple vertical combination type, the spread arch magmatic struc-ture and the arch-bouquet structure. All of them correlate to mantle-origin magmatism, but occur in different places. The spread arch magmatic structures occur within a Mesozoic/Cenozoic rift zone with very thin and hot lithosphere. The vertical combination type of the multi-arch structures occurred near the rift zones where lithosphere was thin and hot. The arch-bouquet magmatic structures occur far from the rift zones where the lithosphere is not hot. The continental rifting acted as the late episode of the lithospheric thinning process seeing that the rift zones usually coincide with the thinnest parts of the lithosphere in East china. In different locations within the lithospheric thinning areas, mantle-origin magmatic activities have different characteristics, which might generate different

关键词： deep seismic reflection, multi-arch structure, eclogite bodies, mantle-origin magmatism, East china.

The relationship between the canonical ENSO and the phase transition of the Antarctic oscillation at the quasi-quadrennial timescale

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Acta Oceanologica Sinica 2010年第6期29卷 26-34页

作者： LIU Changzheng XUE Feng National Climate Center Beijing 100081 China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

A correlation analysis is performed to investigate the relationship between El Nino-Southern Oscillation （ENSO） and the Antarctic oscillation （AAO） at the quasi-quadrennial （QQ） *** is found that the cold tongue index （CTI） and the AAO index （AAOI） are negatively correlated with about a 7-month lead-time,while they are positively correlated with about a 15-month *** further explore this relationship,complex empirical orthogonal function analysis is employed in the QQ sea level pressure （SLP） anomalies from 1951 to *** results indicate that,during the ENSO cycle,there exists one kind of global tropical wave of wavenumber 1 （GTW1） propagating *** the traveling of GTW1,the tropical SLP anomaly tends to intrude into the southern ***,three strong signals travel synchronously along the circumSouth-Pacific path,and a relatively weak signal extends eastward and poleward over the South Ocean in the Atlantic-Indian Ocean *** the propagation of these signals,the AAO phase tends to be reversed *** a result,there exists an evident lead-lag correlation between CTI and *** can be concluded that ENSO plays a key role in the phase transition of AAO at the QQ *** is also noticed that this regular relationship is only evident in the canonical ENSO events,for which sea surface temperature （SST） anomalies extend westward from the tropical eastern *** the other hand,the similar relationships are not found among those atypical ENSO events for which SST anomalies spread eastward from the central Pacific,such as the 1982-1983 ENSO event.

关键词： ENSO Antarctic oscillation the quasi-quadrennial timescale the global tropical wave of wavenumber 1