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MULTISCALE MECHANICAL BEHAVIORS IN DISCRETE materialS: A REVIEW

Acta Mechanica Solida Sinica 2010年第6期23卷 579-591页

作者： Xiaojing Zheng Dengming Wang (Key laboratory of Mechanics on Western Disaster and Environment,the Ministry of Education of china,Lanzhou {2.,Lanzhou 730000,china) [a] Key laboratory of Mechanics on Western Disaster Environment the Ministry of Education of China Lanzhou University Lanzhou 730000 China

The discrete material, which belongs to the category of soft materials, is one of the most prevalent forms of matter in nature and engineering fields. These materials often exhibit abundant and complex mechanical properties which are still far from being perfectly understood. From the view of multi-scale framework concentrated on the ＇bridge＇ role in the macro-micro relation, this review mainly introduces some theoretical investigations of mechanical behaviors in discrete materials, including the continuum constitutive model based on the macroscopic phenomenological approach and coupled micro-macro approach, the statistical analysis of some microscopic physical quantities involved contacted forces between particles and its transmission within the whole system, and the statistical analysis for some microscopic processes in aeolian landform systems involving the grain-bed impact, the transportation and sedimentation of wind-blown sand flux, et al. Finally, some further worthwhile challenges in these fields are suggested.

关键词： discrete material multiple space and time scales trans-scales correlation sanddune statistical analysis

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Lithium isotopic composition of subduction-related leucogranites and associated rocks from the northern margin of the North china craton:Source tracking and tectonic implications

Lithium isotopic composition of subduction-related leucogran...

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中国矿物岩石地球化学学会第13届学术年会

作者： XIAO Yi-lin~1,XU Li-jun~1,GAO Yong-jun~2.LI Shu-guang~1, SUN He~1,GU Hai-ou~1 1.CAS Key laboratory of Crust-Mantle materials and Environments,{2. of earth and space sciences,university of science and technology of china,hefei,2.002. 2.Department of earth and Atmospheric sciences,university of Houston,Houston,TX 772.4,USA

We report Li elemental and isotopic data for a suite of(leuco-) granitic and gneissic rocks(presumed protolith of the leucogranite) from the boundary between the North china craton(NCC) and the South china plate (SCP),which represent an important repository for understanding the Mesozoic thicken and thinning processes of the *** concentrations and isotopic compositions of leucogranites from the Bangbu area in the southern margin of the NCC show the following important characteristics:i) most samples(15 out of 19) have much lower Li concentrations but higherδ Li values compared to normal granite;ii) some samples have very low Li concentrations(around 1 ppm) but extremely heavy isotopic compositions(from 8.6 to 16.1),representing the heaviest Li isotopic compositions so far reported for granitic rocks;iii) lithium isotopic compositions of 11

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On the relationship between the postmidnight thermospheric equatorial mass anomaly and equatorial ionization anomaly under geomagnetic quiet conditions

On the relationship between the postmidnight thermospheric e...

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中国科学院地质与地球物理研究所第11届（2.11年度）学术年会

作者： Jing Liu,Libo Liu,Biqiang Zhao,Jiuhou Lei,and Weixing Wan 1 Beijing National Observatory of space Environment,Institute of Geology and Geophysics,Chinese Academy of sciences,Beijing,china. 2 Also at State Key laboratory of space Weather,Center for space science and Applied Research,Chinese Academy of sciences,Beijing,china. 3 Graduate university of Chinese Academy of sciences,Beijing,china. 4 school of earth and space sciences,university of science and technology of china,hefei,china.

[1]The equatorial mass anomaly(EMA) in the thermosphere and equatorial ionization anomaly(EIA) in the ionosphere are two interesting phenomena in low-equatorial latitude *** studies have shown that the EMA appears between 1000 and 2.00 local time(LT) and its location of trough is aligned with dip equator,indicating the plausible role of the EIA structure in the development of *** this report,we conducted a statistical study of the occurrence of postmidnight EMA and EIA on the basis of the CHAMP in situ measurements during *** results revealed that clear EMA and EIA structures are sometimes visible in the postmidnight sector(0100-0600 LT) during geomagnetic quiet periods(Kp2.00 LT to %at 0600 *** occurrence of postmidnight EIA presents a wave-like pattern;however,no salient feature appears for the longitudinal occurrence of *** EMA is more likely to occur at lower solar activity,whereas an opposite trend presents in the *** the basis of above results,our findings imply that a simple EIA-EMA cause-effect relationship does not hold in the postmidnight sector.

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AGES, Nd AND Sr ISOTOPIC COMPOSITIONS OF THE JIAOZIYAN GABBROIC INTRUSION FROM THE NORTHERN DABIE TERRAIN

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Scientia Geologica Sinica 1998年第1期 30-36页

作者： Chen Daogong and Wu Yuanbao Department of earth and space {2.s, university of science and technology of china, hefei, 2.002.Wang Yinxi and Zhi Xiachen Center of Modern Analyses, Nanjing university, Nanjing 2.0093Xia Qunke Department of Ear

ＡＧＥＳ，ＮｄＡＮＤＳｒＩＳＯＴＯＰＩＣＣＯＭＰＯＳＩＴＩＯＮＳＯＦＴＨＥＪＩＡＯＺＩＹＡＮＧＡＢＢＲＯＩＣＩＮＴＲＵＳＩＯＮＦＲＯＭＴＨＥＮＯＲＴＨＥＲＮＤＡＢＩＥＴＥＲＲＡＩＮＣｈｅｎＤａｏｇｏｎｇａｎｄＷｕＹｕ... 详细信息

ＡＧＥＳ，ＮｄＡＮＤＳｒＩＳＯＴＯＰＩＣＣＯＭＰＯＳＩＴＩＯＮＳＯＦＴＨＥＪＩＡＯＺＩＹＡＮＧＡＢＢＲＯＩＣＩＮＴＲＵＳＩＯＮＦＲＯＭＴＨＥＮＯＲＴＨＥＲＮＤＡＢＩＥＴＥＲＲＡＩＮＣｈｅｎＤａｏｇｏｎｇａｎｄＷｕＹｕａｎｂａｏＤｅｐａｒｔｍｅｎｔｏｆ...

关键词： Nd AND ISOTOPIC Sr AGES

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Partial melting of carbonated mantle: element and isotope evidence from Cenozoic continental basalt in east-central china

Partial melting of carbonated mantle: element and isotope ev...

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International Conference on Continental Volcanism

作者： Yong-Fei Zheng. Zi-Fu Zhao Jun-Jun Zhang Xia-Chen Zhi Yi-Liang Li and Bing Gong CAS Kay laboratory of Crust-Mantle materials and Environments {2. of earth and space sciences university of science and technology of china hefei 2.002. {12.

＜正＞Although high-pressure experiments have suggested that OIB-like alkalic basalts can originate from partial melting of carbonated peridotite, no continental basalt is tested to fit such an origin. A combined study of trace elements and Nd-Sr-O-C isotopes were carried out on Miocene continental basalts at eastern Anhui in east-central china. The results suggest that the continental basalts were derived from partial melting of carbonated, fertile mantle source.

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Text Clustering Algorithm Based on Spectral Graph Seriation

Text Clustering Algorithm Based on Spectral Graph Seriation

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2.09中国控制与决策会议

作者： Guo Wensheng~1,Li Guohe~2.1.Department of Computer science and technology,{2. university of Petroleum-Beijing,Beijing Changping 102.49 Key laboratory of earth Prospecting and Information technology Beijing,Beijing Changping 102.49 2.Department of Computer science and technology,{2. university of Petroleum-Beijing,Beijing Changping 102.49

＜正＞In the field of information processing,most of the existing text clustering algorithm is based on Vector space Model（VSM）.However,VSM can not effectively express the structure of the text so that it can not fully express the semantic information of the *** order to improve the ability of expression in the semantic information,this paper presents a new text structure graph *** the weighted graph,this model expresses the characteristics term of the text and its associated location *** this basis of spectral graph seriation,a spectral clustering algorithm is put *** algorithm replace solving common subgraph with matrix computation,then reduce the computational complexity of graph *** are also algorithm analysis and experiment in the *** results of the study show that the text clustering algorithm based on spectral graph seriation is effective and feasible.

关键词： Graph Model Spectral Graph Theory Text Clustering

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Enhancement of Solar Energetic Particles During A Shock Propagating through A Preceding Magnetic Cloud

Enhancement of Solar Energetic Particles During A Shock Prop...

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第十二届全国日地空间物理学术讨论会

作者： Chenglong Shen~1 Yuming Wang~1 Pinzhong Ye~1 Shui Wang~1 (1 CAS Key laboratory of Basic Plasma Physics,school of {2. & space sciences.,university of science & technology of china,hefei,Anhui 2.002.,P.R.china

＜正＞Five cases of magnetic clouds （MCs） overtaken by shocks are reported by investigating the magnetic field and solar wind plasma data observed by ACE *** integral proton flux data observed by GOES spacecraft are...

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Seismic velocity structures and detailed features of the D”discontinuity near the core-mantle boundary beneath eastern Eurasia

Seismic velocity structures and detailed features of the D”...

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中国科学院地质与地球物理研究所第11届（2.11年度）学术年会

作者： Yumei He~(a,b,*),Lianxing Wen~(b,c) a Key laboratory of the earth’s Deep Interior,Institute of Geology and Geophysics,Chinese Academy of {2.s,Beijing 10002.,PR china b Department of Ceo{2.s,State university of New York at Stony Brook,Stony Brook,NY 11790,USA c school of earth and space {2.s,university of {2. and {12. of china,hefei,Anhui 2.002.,PR china

Shear and compressional velocity structures and features of the D" discontinuity near the core-mantle boundary(CMB) beneath eastern Eurasia are studied based on forward waveform modeling and differential -travel-time analysis of ScSH-SH,sScS-sS,PcP-P and pPcP-pP ***-quality differential-travel-time analysis reveals two high-velocity patches spanning a width of 3000 km and separated by a 300-km wide normal velocity *** maximum shear and compressional velocity perturbations reach 3.8%and 2.7%,*** data indicate that the D" discontinuity emerges in the high velocity patches and disappears in the normal-velocity ***,the features of the D" discontinuity,although constrained by rather sparse seismic data,vary from diffusive discontinuities in the eastern patch to sharp discontinuities in the western *** D" discontinuities occur at about 2.0 km above the CMB in the eastern patch with a shear velocity jump of 3.0-5.0%and a transitional depth of at least 100 km,and at 2.0 km above the CMB in the western patch with an abrupt shear velocity jump of 5.0%.A diffusive P wave discontinuity is also observed in the eastern patch with the similar features of the S wave *** inferred features of the D" discontinuity can be explained by the post-perovskite transformation in the lower *** observations that the D" discontinuities occur only in the high-velocity patches may be due to the effect of the positive Clapeyron slope of the post-perovskite transition,and the varying transitional depths of the D" discontinuity in the high-velocity regions may be caused by the compositional effects on the post-perovskite transition in the presence of strong variations of composition within the high-velocity *** high-velocity patches geographically correlate with the subduction of the Pacific and Indian plates in the past 30-60 Ma,and the normal-velocity gap falls into the subduction gap between the Pacific and Indian plates

关键词： Seismic velocity structure Core-mantle boundary D"discontinuity Eastern Eurasia

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Longitudinal variations of electron auroral precipitation

Longitudinal variations of electron auroral precipitation

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第十四届全国日地空间物理学术研讨会

作者： Xiaoli Luan1,2.Wenbin Wang2.Jiyao Xu3 Jiuhou Lei1 and Xiankang Dou1 (1 school of earth and {2. sciences, university of science and technology of china, hefei, 2.002. ) (2.High Altitude Observatory, National Center for Atmospheric Research, Boulder, CO, USA ) (3 State Key laboratory of {2. Weather, Center for {2. sciences and Applied Research, Chinese Academyof sciences, Beijing, 100190 )

极光是太阳风-磁层-电离层耦合在地球高纬区的一个重要现象。极光沉降粒子半球能量（Auroral hemispheric power）代表一个半球内因极光活动而注入的沉降粒子的总能量。该能量对电离层/热层过程有重要影响,是大型电离层/热层理论模式（...

极光是太阳风-磁层-电离层耦合在地球高纬区的一个重要现象。极光沉降粒子半球能量（Auroral hemispheric power）代表一个半球内因极光活动而注入的沉降粒子的总能量。该能量对电离层/热层过程有重要影响,是大型电离层/热层理论模式（如NCAR-TIEGCM）的关键输入参量之一。现通过TIMED/GUVI观测发现,夜间区域极光粒子沉降能量以及极光沉降粒子的半球能量具有显著的经度变化（或世界时变化）。在较低地磁活动条件下（Kp＜=1-4）,其经度变化幅度可达40%。且该变化特征依赖于不同的季节和半球。POLAR/UVI的观测也证实了北半球极光沉降粒子半球能量存在显著的经度和季节变化。

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An overview of resistive random access memory devices

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science Bulletin 2011年第Z2期 3072-3078页

作者： LI YingTao 1,2., LONG ShiBing 2., LIU Qi 2., Lü HangBing 2., LIU Su 1 & LIU Ming 2. 1 school of Physical science and {2., Lanzhou university, Lanzhou 730000, china 2.laboratory of Nano-Fabrication and Novel Device Integration, Institute of Microelectronics, Chinese Academy of sciences, Beijing 10002., china

With recent progress in material science, resistive random access memory (RRAM) devices have attracted interest for nonvolatile, low-power, nondestructive readout, and high-density memories. Relevant performance parameters of RRAM devices include operating voltage, operation speed, resistance ratio, endurance, retention time, device yield, and multilevel storage. Numerous resistive-switching mechanisms, such as conductive filament, {2.-charge-limited conduction, trap charging and discharging, Schottky Emission, and Pool-Frenkel emission, have been proposed to explain the resistive switching of RRAM devices. In addition to a discussion of these mechanisms, the effects of electrode materials, doped oxide materials, and different configuration devices on the resistive-switching characteristics in nonvolatile memory applications, are reviewed. Finally, suggestions for future research, as well as the challenges awaiting RRAM devices, are given.

关键词： resistive random access memory resistive switching performance parameters

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