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PAT study on stress-field pinning in high-Tc superconductors

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Science China Mathematics 1997年第9期40卷 978-984页

作者：李阳王耘波唐春光马庆珠曹国辉魏龙王文华张天保 Also at National Laboratory for Superonductivity Chinese Academy of SeiencesBeijing 100080China. Department of Materials Physics University of Science and Technology BeijingBeijing 100083China Laboratory of Nuclear Analysis Techniques Chinese Academy of SciencesBeijing 100080China) Also at National Laboratory for SuperonductivityChinese Academy of SeiencesBeijing 100080China

The simultaneous measurements of Doppler-broadened radiation spectra and lifetime spectra were performed by positron annihilation analysis on Eu-doped Y-123 *** the doping concentration reaches 30 % and 70 %,the density of defeat and its stress-field reach the maximum for (Y1-xEux) Ba2Cu3O7-y The pinning mechanism of such superconductors is discussed,and the results support the stress pinning mechanism.

关键词： Y-123 superconductor Eu-doping stress-field pinning.

Characterization of turbulent flux transfer over a Gobi surface with quality-controlled observations

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Science China Earth Sciences 2011年第5期54卷 753-763页

作者： ZHOU DeGang HUANG RongHui Centre for Monsoon System Research Institute of Atmospheric Physics Chinese Academy of Seiences Beijing 100190 China

This study evaluates the spatial distributions in the quality of momentum and sensible heat fluxes,and determines the turbulent transfer characteristics with quality-controlled *** research is based on raw turbulence data collected over a Gobi surface in the Dunhuang area in June *** results indicate that part of the momentum fluxes are of poor quality in the daytime and *** poor quality of the momentum fluxes in the daytime is mainly attributed to the development of *** footprint reveals that,in general,the momentum fluxes and sensible heat fluxes can be measured well in the east and west upwind sectors under unstable *** relationship between the non-dimensional standard deviation of the wind components and atmospheric stability follow the "1/3 power law",which supports the Monin-Obukhov similarity ***,this study identifies a clear disturbance in the measurements surrounding the Gobi *** momentum roughness length of z0m=0.59 mm is determined after excluding such disturbance,and the additional resistance during the daytime is proposed to be an average of 3.1,although its actual value is highly *** study discusses the applicability of several thermodynamic parameterization schemes for the Gobi *** results show that the scheme κB-1=3.1 can represent well the summer diurnal turbulent heat transfer.

关键词： Gobi surface turbulent transfer surface roughness length quality control

Validation of three infiltration models on purple soil under simulated rainfall

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Progress in Natural Science:Materials International 2007年第9期17卷 1059-1066页

作者： Wang Yukuan1,2,Fu Bin1,3,Xu Pei1,2,Wang Daojie1,2,Wang Xiantuo1,3 and Wang Yongqiang1,3(1.Key Laboratory of Mountain Surface Process and Hazards,chinese academy of seiences,Chengdu 610041,China 2.Institute of Mountain Hazards and Environment,chinese academy of Sciences,Chengdu 610041,China 3.Graduate university of the chinese academy of Sciences,Beijing 100049,China) Key Laboratory of Mountain Surface Process and Hazards Chinese Academy of Seiences Chengdu 610041 China Institute of Mountain Hazards and Environment， chinese academy of Sciences， Chengdu 610041 China Graduate university of the chinese academy of Sciences Beijing 100049 China

So as to find models suitable for the prediction of water infiltration in purple soil,infiltration rates simulated by three popular empirical infiltration models,Horton model,Kostiakov model,and the modified Kostiakov model,were compared by using those observed results on slope in purple soil under rainfall simulation.28 sets of infiltration data were divided into two parts for parameter estimation and validation *** performance of the three infiltration models was evaluated with the Nash and Sutcliffe efficiency *** results show that the percent for Nash and Sutcliffe efficiency greater than 0.7 is about 69.7% for the Horton model,and 48.48%,and 54.55% for the Kostiakov model and the modified Kostiakov model,*** model is better than Kostiakov model and the modified Kostiakov model in most rain events in the ***,Kostiakov model is still suitable for reasonable prediction of the infiltration in purple soil sloping farmland because fewer parameters are ***,rainfall intensity has significant effects on the parameter values used in the simulation *** simulation results can be improved by choosing suitable parameters according to the rainfall intensity.

关键词： infiltration model sloping farmland purple soil rainfall simulation

China＇s Graphite Resources and the Supply-Demand Situation

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Acta Geologica Sinica(English Edition) 2018年第4期92卷 1645-1646页

作者： LIU Lian LIU Zhiqiang HUANG Min FEI Hongcai ZHOU Jian ZHANG Yuxu HAO Ziguo chinese academy of Geological seiences China Geological Society Beij'ing 100037 China

Graphite is a rare and important nonmetallic mineral. Till 2017, the global graphite resource reserves had exceeded one billion tons, which are mainly distributed in China （0.45 billion tons）, Mozambique （0.14 billion tons）, Madagascar （0.1 billion tons）, Turkey （0.09 billion tons）, Brazil （0.07 billion tons）, and Tanzania （0.07 billion tons）. These six countries include about 92% of the global graphite resource reserves, of which China accounts for about 45% of the world＇s total resource reserves.

关键词： Graphite In China’s Graphite Resources and the Supply-Demand Situation

Sulfur isotopic composition of the Tianqiao Pb-Zn ore deposit,Northwest Guizhou Province,China:Implications for the source of sulfur in the ore-forming fluids

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chinese Journal Of Geochemistry 2010年第3期29卷 301-306页

作者： ZHOU Jiaxi HUANG Zhilong ZHOU Guofu LI Xiaobiao DING Wei BAO Guangping The State Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China The Graduate university Chinese Academy of Seiences Beijing 100049 China

The Tianqiao Pb-Zn ore deposit of Guizhou Province, China, is located in the mid-east of the Sichuan-Yunnan-Guizhou Pb-Zn-Ag multi-metallic mineralization area, which is representative of the Pb-Zn ore de-posits in this area. It consists of three main orebodies, whose Pb+Zn reserves are more than 0.2 million ton. This paper analyzes the sulfur isotopic composition of these orebodies. The data show that the ore minerals (galena, sphalerite, pyrite) in these orebodies are enriched in heavy sulfur, with δ34SV-CDT values varying between 8.35‰ and 14.44‰, i.e. the δ34SV-CDT values of pyrite are between 12.81‰ and 14.44‰, the mean value is 13.40‰; the δ34SV-CDT values of sphalerite are range from 10.87‰ to 14.00‰, the mean value is 12.53‰; the δ34SV-CDT values of galena are range from 8.35‰ to 9.83‰, the mean value is 8.84‰, and they have the feature of δ34Spyrite>δ34Ssphalerite>δ34Sgalena, which indicates the sulfur isotope in ore-forming fluids has attained equilibrium. The δ34S V-CDT values of the deposit are close to those of sulfates from carbonate strata of different ages in the ore-field (15‰), which suggests that the sulfur in the ore-forming fluids should be derived from the thermo-chemical sulfate reduction of sulfates from the sedimentary strata.

关键词：硫同位素组成成矿流体来源铅锌矿贵州省天桥中国西北部硫酸盐还原

Bounding of near-fault ground motion based on radiated seismic energy with a consideration of fault frictional mechanisms

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Earthquake Science 2010年第4期23卷 357-368页

作者： Baoping Shi Boyan Liu Lingyuan Meng Earth Science Colleg the Graduate School Chinese Academy of Seiences Beijing 100049 China

The energy radiated as seismic waves strongly depends on the fault rupture process associated with rupture speed and dynamic frictional mechanisms involved in the fault slip motion. Following McGarr and Fletcher approach, we derived a physics-based relationship of the weighted average fault slip velocity vs apparent stress, rupture speed and static stress drop based on a dynamic circular fault model. The resultant function can be approximately used to bound near-fault ground motion and seismic energy associated with near-fault coseismic deformation. Fault frictional overshoot and under- shoot mechanisms governed by a simple slip-weakening constitutive relation are included in our consideration by using dy- namic rupture models named as M- and D-models and proposed by Madariaga （1976） and Boatwright. We applied the above function to the 2008 great Wenchuan earthquake and the 1999 Jiji （Chi-Chi） earthquake to infer the near-fault ground motion called slip weighted average particle velocity and obtained that such model-dependent prediction of weighted average ground velocities is consistent to the results derived from the near-fault strong motion observations. Moreover, we compared our re- sults with the results by McGarr and Fletcher approach, and we found that the values of the weighted average particle veloci- ties we obtained for these two earthquakes are generally smaller and closer to the values by direct integration of strong mo- tion recordings of the near-fault particle velocity waveform data. In other words, if this result comes to be true, it would be a straightforward way used to constrain the near-fault ground motion or to estimate source parameters such as rupture speed, static and dynamic stress drops.

关键词： stress drop radiated energy apparent stress circular-fault-model rupture speed

Microphysical Structure of a Nimbostratus over Jilin Province Provided by Airborne Observations

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Atmospheric and Oceanic Science Letters 2009年第6期2卷 362-367页

作者： ZHAO Zhen LEI Heng-Chi Institute of A tmospheric Physics Chinese Academy of Seiences Beijing 100029 China

Airborne measurements were collected during a stepwise ascent within a nimbostratus cloud associated with a cold vortex depression over the Jilin Province on 21 June 2005 to study cloud structure and ice particle spectra. The melting layer of the nimbostratus was clearly defined in the radar images. The microphysical structure of the nimbostratus was elucidated by a King liquid water probe and Particle Measuring Systems （PMS） probes aboard the research aircraft. The PMS 2-D images provided detailed information of ice crystal transformations. A thick layer of supercooled cloud was observed, and the high ice particle concentrations at temperatures ranging from -3℃ to -6℃ were consistent with Hallett-Mossop ice multiplication. The shape of ice crystals from near the cloud top to the melting layer were in the form of columns, needles, aggregations, and plates. In addition, significant horizontal variability was evident on the scale of few hundred meters. Particle spectra in this cloud were adequately described by exponential relationships. Relationship between the intercept （No） and slope （2） parameters of an exponential size distribution was well characterized by a power law.

关键词： PMS cloud structure ice multiplication particle spectra

High Speed and Ultra-Low-Power Phase Change Line Cell Memory Based on SiSb Thin Films with Nanoscale Gap of Electrodes Less Than 100 nm

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chinese Physics Letters 2008年第11期25卷 4174-4176页

作者：吕士龙宋志棠张挺封松林 Nanotechnology Laboratory Research Center of Functional Semiconductor Film Engineering and Technology Shanghai Institute of Micro-system and Information Technology Chinese Academy of Seiences~ Shanghai 200050 Graduate School of the chinese academy of Sciences Beijing 100049

Si16Sbs4-based line cell phase change random access memory （PCRAM）, in which the Si16Sbs4 phase change line is contacted by TiN electrodes with a nanoscale gap, is fabricated by electron beam lithography. The lowest current and measured pulse width for RESET operation are 115 μA and 18 ns, respectively. The measured shortest pulse width for recrystallization is 110ns, with applied pulse amplitude of 1.5 V. SET and RESET currents for line cells with different line lengths are determined. Endurance of 106 cycles with a resistance ratio of above 800 has been achieved.

关键词： the power-law exponents precipitation durative abrupt precipitation change

Spectra of L-band ionospheric scintillation over Nanjing

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chinese Science Bulletin 2012年第25期57卷 3375-3380页

作者： FANG HanXian YANG ShengGao WANG SiCheng Institute of Meteorology PLA University of Science and TechnologyNanjing 211101China State Key Laboratory of Space Weather Chinese Academy of SeiencesBeijing 100190China

We report the spatiotemporal statistical characteristics of amplitude scintillation over Nanjing.A FFT method for computing scintillation intensity power spectra is briefly *** this method,the data with ISATM in Nanjing is *** characteristic is presented and the irregularities property is discussed *** results reveal that the power spectra obtained for Nanjing is consistent with theoretical *** frequencies below the Fresnel frequency,the power density plotted on log-log scale is almost constant whereas above it asymptotes to a straight *** spectral index ranges from 1.71 to 1.92,which has positive correlation with the S 4 ***,the average drift velocity of irregularities is computed assumably and compared with that obtained for Xinxiang and Haikou.

关键词：电离层闪烁光谱特性南京 L-波段违规行为 FFT方法幅度闪烁统计特征