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Relationship between surface subsidence factor and mining depth of strip pillar mining

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中国有色金属学会会刊：英文版 2011年第S3期21卷 594-598页

作者： GUO Wen-bing1, 2, HOU Quan-lin 1, zou You-feng2 1. College of Earth Science, Graduate University of chinese academy of sciences, beijing 100049, china 2. School of energy Science and Engineering, Henan Polytechnic University, Jiaozuo 454000, china College of Earth Science Graduate University of Chinese Academy of Sciences Beijing 100049 China School of energy Science and Engineering Henan Polytechnic University Jiaozuo 454000 China

Strip pillar mining is one of the most important technical measures to control mining subsidence in china. Mining depth is one of the most important factors that can affect the mining subsidence in strip pillar mining. Six numerical simulation models were set up to simulate the surface subsidence of strip pillar mining in different mining depths. The mining depth in these six models ranges from 300 to 800 m. The simulated results were compared and analyzed. The formula was established based on the simulated results. It demonstrated that the subsidence of strip pillar mining method is related to mining depth. While the other conditions are the same, the subsidence of strip pillar mining increases with the increase of mining depth by logarithmic relationship.

关键词： subsidence factor strip pillar mining mining depth numerical simulation

Effect of the Small Reaustenized Grains on the Mechanical Properties of a HSLA Steel

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Journal of Iron and Steel Research International 2011年第S1期18卷 312-315页

作者： ZHAO Lian-yu 1,2,WEI Yan 1,SHAN Yi-yin 1,YANG Ke 1 (1.institute of Metal Research,chinese academy of sciences,Shenyang 110016,Liaoning,china 2.Graduate School of chinese academy of sciences,beijing 100049,china) chinese Acad Sci Inst Met Res Shenyang 110016 Liaoning Peoples R China chinese Acad Sci Grad Sch Beijing 100049 Peoples R China

Grain refinement improves not only strength but also *** reaustenized grains were discovered to form along the grain boundaries and lath boundaries in an as rolled high-strength low-alloy (HSLA) steel when heated to double phase *** number and size of the small reaustenized grains were revealed to depend mainly on temperature in the range of 700 to 760℃.These small reaustenized grains were deduced to form by consuming *** mechanical property tests showed that they resulted in slight changes to tensile ***,the sample heated at 740℃ produced a peak Charpy V-notch (CVN) impact energy of 248J when tested at-30℃.Fractography showed that the facture surface of the 740℃ heated impact sample exhibited the smallest brittle zone away from the notch root and a large dimple zone lay ahead of the notch tip,which demonstrated the highest toughness.

关键词： high-strength low-alloy steel reaustenization grain refinement tensile property

An Explicit Function Expression for dc Bias and Temperature Dependence of Magnetoresistances in Magnetic Tunnel Junctions

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Journal of Materials Science & Technology 2002年第6期18卷 497-501页

作者： Xiufeng HANState Key Laboratory of Magnetism, institute of physics and Center of Condensed Matter physics, chinese academy of sciences, beijing 100080, china chinese Acad Sci Inst Phys State Key Lab Magnetism Beijing 100080 Peoples R China chinese Acad Sci Ctr Condensed Matter Phys Beijing 100080 Peoples R China

An explicit function expression for the bias voltage or/and temperature dependences of tunnel magnetoresistance ratio and resistances were obtained with a unique set of intrinsic parameters. Two of these intrinsic parameters are the Curie temperature TC and the density of state (DOS) for itinerant majority and minority electrons ξ(ρM/ρm), which are the eigen parameters of ferromagnetic electrodes. Others are the spin-dependent matrix-element ratio (i.e., |Td|2/|TJ|2 ) and the anisotropic-wavelength-cutoff energy ECγ of spin-wave spectrum in magnetic tunnel junction (MTJ), which are the structure parameters of an MTJ. These intrinsic parameters can be predetermined using the experimental measurement or, in principle, using the first-principle calculation method for an MTJ with the three key layers of FM/I/FM. Furthermore, a series of experimental data for an MTJ, for example, a spin-valve-type MTJ of Ta (5 nm)/Ni79Fe21(25 nm)/lr22Mn78(12 nm)/Co75Fe25(4 nm)/AI(0.8 nm)-oxide/Co75Fe25(4 nm)/Ni79Fe21(20 nm)/Ta (5 nm) in this work, can be self-consistently evaluated and explained using such concise explicit function formulations.

关键词： Magnetic tunnel junction TMR Spin-electron transport Magnon excitation Spin-polarization Magnetotransport

Brownian ratchets driven by flashing noise strength

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chinese Science Bulletin 1999年第21期44卷 1956-1961页

作者： ZHAO Tongjun, ZHAN Yong, ZHUO Yizhong and WU XizhenDepartment of Applied Mathematics and physics , Hebei University of Technology , Tianjin 300130, china china institute of Atomic energy, beijing 102413, china institute of Theoretical physics, chinese academy of sciences , beijing 100080, china Corresponding author Dept. of Appl. Math. and physics Hebei University of Technology Tianjin 300130 China china institute of Atomic energy Beijing 102413 China institute of Theoretical physics Chinese Academy of Sciences Beijing 100080 China

The stochastic transport driven by flashing multi-noise sources in a ratchet is studied. The stationary current versus the noise strength and the colored noise correlated time T is obtained . At a fixed flip rate and strength of the colored noises, the novel phenomenon of the current reversal occurs as T reaches a certain value. More than one reversal point exists when

关键词： flashing force ratchet current reversal Langevian equation.

An SGS Model and Its Application

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Communications in Nonlinear Science and Numerical Simulation 1999年第2期4卷 87-90页

作者： Zhengtong XIE Jiachun LI (institute of Mechanics, chinese academy of sciences, beijing 100080, china) institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

Based on the turbulent energy and structure function model, a subgridstress model named transitional structure function (TSF) is proposed, which exhibitsmore satisfactory performance than the previous one when applied in turbulent flow withinand above forest *** time and horizontal averaged statistics such as mean verticalprofiles of wind velocity, Reynolds stress, turbulent kinetic energy etc., and instantaneousfields as well are in general agreement with earlier observations, at least in a qualitativesense.

关键词： Large-Eddy simulation SGS model turbulent flow canopy

A SAR sidelobe suppression algorithm based on modified spatially variant apodization

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Science china(Technological sciences) 2010年第9期53卷 2542-2551页

作者： NI Chong1,2,WANG YanFei1,XU XiangHui1,ZHOU ChangYi1 & CUI PengFei1,2 1 institute of Electronics,chinese academy of sciences,beijing 100190,china 2 Graduate University of chinese academy of sciences,beijing 100039,china institute of Electronics Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China

The existing spatially variant apodizations (SVAs) either cannot depress the sidelobes effectively or reduce the energy of the *** improve this,a modified SVA (MSVA) is put forward in this paper,which expands the traditional filter from 3-taps to 5-taps and sets relevant parameters according to different sampling rates to get the excellent result that satisfies constrained optimization theory.A method for synthetic aperture radar (SAR) sidelobe control based on MSVA is presented,which applies MSVA to range compression and azimuth compression to control *** method which is available for any Nyquist sampling rate can both depress the sidelobes effectively and keep the energy of the mainlobe and the resolution of the *** method can reduce sidelobe levels more effectively than classical amplitude weighting while maintaining the image resolution,as demonstrated by the result of the experiment.

关键词： synthetic aperture radar sidelobe suppression resolution SVA

Effects of diatoms on reproduction and growth of marine copepods

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Progress in Natural Science:Materials International 2004年第10期14卷 1-7页

作者： ZHANG Guangtao 1,2 and SUN Song 1 (1.Key Laboratory of Marine Ecology&Environment sciences,institute of Oceanology,chinese academy of sciences,Qingdao266071,china 2.Graduate School,chinese academy of sciences,beijing100039,china) Lab. of Marine Ecology Inst. of Oceanology Chinese Acad. of Sci. Qingdao 266071 China Graduate Sch. Chinese Acad. of Sci. Beijing 100039 China

Two hot spots in marine ecology,deleterious effects of diatoms and feeding selectivity of copepods,as well as new progress on these two issues achieved in the recent ten years,are *** two issues are considered correlated *** and their metabolites can induce deleterious effects on growth,reproduction and development of copepods,including increase of mortality and decrease of egg production,hatching and growth *** negative effects,resulting from either chemical toxin or nutritional defi-ciency,can be conquered in natural environments by diverse *** is therefore concluded that deleterious effects of diatoms observed in laboratory or during blooming period are only a special case that accommodation of feeding strategy of copepods is *** under-stand their feeding strategy in natural environments is a prerequisite to explaining the mechanisms of deleterious effects caused by diatoms,and makes it possible to re-evaluate the energy flow in marine ecosystems.

关键词： diatoms copepod feeding strategy reproduction deleterious effects

Chemical and mineralogical characterizations of a copper converter slag

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Rare Metals 2002年第3期21卷 175-181页

作者： DENG Tong and LING Yunhaninstitute of Chemical Metallurgy, chinese academy of sciences, beijing 00080, china institute of Chemical Metallurgy Chinese Academy of Sciences 北京 100080

A copper converter slag was examined chemically and mineralogically to determine its existing phases, in particular those containing Co and Cu. The slag consists predominantly of fayalite and magnetite, together with some glass, chalcocite, and metallic copper. Copper is entrapped in the slag mostly as chalcocite and metallic copper, as well as trace copper oxide. There was no indication of any independent Co mineral in the slag, but Co was found to be enriched in fayalite and megnetite as solid solution, although Co was detected in all the phases of the slag by SEM-EDX (scanning electron microscopy equipped with model EDAX-9100 energy dispersive spectrometer) and WDS (model WDX-2A X-ray wave-length dispersive spectrometer).

关键词： Cu Co converter slag characterization

Comparison of dark energy models:A perspective from the latest observational data

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中国科学：物理学、力学、天文学英文版 2010年第9期53卷 1631-1645页

作者： LI Miao1,2,LI XiaoDong2.3 & ZHANG Xin1,4 1Kavli institute for Theoretical physics china,chinese academy of sciences,beijing 100190,china 2Key Laboratory of Frontiers in Theoretical physics,institute of Theoretical physics,chinese academy of sciences,beijing 100190,china 3Interdisciplinary Center for Theoretical Study,University of Science and Technology of china,Hefei 230026,china 4Department of physics,College of sciences,Northeastern University,Shenyang 110004,china Kavli institute for Theoretical physics china Chinese Academy of Sciences Beijing China Key Laboratory of Frontiers in Theoretical physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing China Interdisciplinary Center for Theoretical Study University of Science and Technology of China Hefei China Department of physics College of Sciences Northeastern University Shenyang China

We compare some popular dark energy models under the assumption of a flat universe by using the latest observational data including the type Ia supernovae Constitution compilation,the baryon acoustic oscillation measurement from the Sloan Digital Sky Survey,the cosmic microwave background measurement given by the seven-year Wilkinson Microwave Anisotropy Probe observations and the determination of H0 from the Hubble Space *** comparison statistics such as the Bayesian and Akaike information criteria are applied to assess the worth of the *** statistics favor models that give a good fit with fewer *** on this analysis,we find that the simplest cosmological constant model that has only one free parameter is still preferred by the current *** other dynamical dark energy models,we find that some of them,such as the αdark energy,constant w,generalized Chaplygin gas,Chevalliear-Polarski-Linder parametrization,and holographic dark energy models,can provide good fits to the current data,and three of them,namely,the Ricci dark energy,agegraphic dark energy,and Dvali-Gabadadze-Porrati models,are clearly disfavored by the data.

关键词： dark energy models observational constraints model comparison information criteria