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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 {2.,chinese academy of sciences,beijing 100190,{2. 2.ey laboratory of frontiers in Theoretical physics,institute of Theoretical physics,chinese academy of sciences,beijing 100190,{2. 3Interdisciplinary Center for Theoretical Study,University of Science and Technology of {2.,Hefei 2.002.,{2. 4Department of physics,College of sciences,Northeastern University,Shenyang 110004,{2. Kavli institute for Theoretical physics {2. Chinese Academy of Sciences Beijing China Key laboratory of {2. 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

Interference pattern generation and simulation in the single beam of a white light continuum

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Science china(physics,Mechanics & Astronomy) 2010年第6期53卷 1060-1064页

作者： YU ZhiHao & WENG YuXiang laboratory of Soft Matter physics,{2. of physics,chinese academy of sciences,and National laboratory of Condensed Matter physics,beijing 100190,china laboratory of Soft Matter physics Institute of Physics Chinese Academy of Sciences and National Laboratory of Condensed Matter Physics Beijing China

We demonstrate the interference phenomenon in the White Light Continuum(WLC) generated by a single femtosecond laser beam. Different kinds of spatial interference patterns of the WLC generation under various conditions were investigated. The spatial patterns were attributed to interference between the filaments in the WLC generated by the fundamental laser beam yielding the diffraction effect from spatial confinement. Simulations of different patterns were performed. By comparing the results of simulation with those of experiments,the distances of several micrometers between the neighboring filaments can be derived,which agree with the literature values from direct measurements.

关键词： interference supercontinuum generation ultrafast nonlinear optics

A systematic investigation of high harmonic generation using mid-infrared driving laser pulses

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Science china(physics,Mechanics & Astronomy) 2010年第6期53卷 1054-1059页

作者： YAO JinPing 1,2.,XIONG Hui 1 ,XU Han 1 ,FU YuXi 1,2.,ZENG Bin 1,2.,CHU Wei 1,2.,CHENG Ya 1 ,XU ZhiZhan 1 ,LIU XiaoJun 3 & CHEN Jing 4,5 1 State Key laboratory of High Field Laser {2.,Shanghai institute of Optics and Fine Mechanics,chinese academy of sciences,Shanghai 2.1800,china 2.Graduate University of chinese academy of sciences,beijing 100049,china 3 State Key laboratory of Magnetic Resonance and Atomic and Molecular {2.,Wuhan institute of {2. and Mathematics,chinese academy of sciences,Wuhan 430071,china 4 institute of Applied {2. and Computational Mathematics,beijing 100088,china 5 Center for Applied {2. and Technology,Peking University,beijing 100084,china State Key laboratory of High Field Laser {2. Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai China Graduate University of chinese academy of sciences Beijing China State Key laboratory of Magnetic Resonance and Atomic and Molecular {2. Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan China institute of Applied physics and Computational Mathematics Beijing China Center for Applied physics and Technology Peking University Beijing China

We report on a systematic investigation of the influences of gas pressure,focal position and focusing geometry on high harmonic generation by use of mid-infrared femtosecond laser pulses. We also discuss the spatial characteristics of harmonics under different focusing conditions. By optimizing the parameters,we experimentally observed the generation of 1 kHz,low divergence coherent X-ray beams in the water-window region.

关键词： mid-infrared laser pulses high harmonic generation water window

Identification of ten new Galactic HII regions

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Science china(physics,Mechanics & Astronomy) 2010年第6期53卷 1144-1152页

作者： RUAN GuiPing 1,2.& SHI WeiBin 1,2.1 Shandong Provincial Key laboratory of Optical Astronomy and Solar-Terrestrial Environment,School of Space Science and {2.,Shandong University at Weihai,Weihai 2.42.9,china 2.Key laboratory of Optical Astronomy,National Astronomical Observatories,chinese academy of sciences,beijing 100012.china Shandong Provincial Key laboratory of Optical Astronomy and Solar-Terrestrial Environment School of Space Science and Physics Shandong University at Weihai Weihai China Key laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing China

We discovered ten large HII regions in the Sino-German λ6 cm polarization survey of the Galactic plane. They have been identified according to their flat spectral indexes and the high ratio between the 60 μm infrared emission and the λ6 cm emission. The integrated flux densities as well as the sizes of these sources are given at 4800 MHz. Cross-identifications are made with other major radio catalogs.

关键词： radio continuum general-methods observational-HII regions

On Post-Shear-Instability in Saturated Soils

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地学前缘 2009年第S1期16卷 262-263页

作者： Xiaobin Lu~1,Xuhui Zhang~2.1.institute of Mechanics,chinese academy of sciences,{2. 100080,china. 2.institute of Mountain Hazard and Environment,chinese academy of sciences,Chengdu china,

The study on the development of shear band is very import since it is the main reason of landslide. According to experimental results,there is only one shear band forming at last when the soil specimen beard shear loa... 详细信息

关键词： shear band landslide finite amplitude disturbances

Large-eddy simulation of flows past a flapping airfoil using immersed boundary method

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Science china(physics,Mechanics & Astronomy) 2010年第6期53卷 1101-1108页

作者： YANG XiaoLei,HE GuoWei & ZHANG Xing The State Key laboratory of Nonlinear Mechanics,{2. of Mechanics,chinese academy of sciences,beijing 100190,china The State Key laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing China

The numerical simulation of flows past flapping foils at moderate Reynolds numbers presents two challenges to computational fluid dynamics: turbulent flows and moving boundaries. The direct forcing immersed boundary(IB) method has been developed to simulate laminar flows. However,its performance in simulating turbulent flows and transitional flows with moving boundaries has not been fully evaluated. In the present work,we use the IB method to simulate fully developed turbulent channel flows and transitional flows past a stationary/plunging SD7003 airfoil. To suppress the non-physical force oscillations in the plunging case,we use the smoothed discrete delta function for interpolation in the IB method. The results of the present work demonstrate that the IB method can be used to simulate turbulent flows and transitional flows with moving boundaries.

关键词： transitional flows moving boundary immersed boundary method smoothed discrete delta function

MINERALIZATION AGES OF GOLD-HYDROTHERMAL DEPOSITS IN NORTHERN ZONE OF EASTERN KUNLUN MOUNTAINS BASED ON FISSION TRACK ANALYSIS

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地学前缘 2000年第S1期7卷 329-330页

作者： Yuan Wanming 1,Wang Shicheng 1,Mo Xuanxue 2.Wang Lanfen 1[WT5,5”BX](1 institute of High Energy physics, {2., beijing 100080,china 2.china University of Geosciences, beijing 100083,china)

The age of mineralization in a mining area is a primary factor in various researches related to ore\|forming process. It is that the uncertainty of mineralization ages of gold ore deposits in northern zone of eastern Kunlun Mountains, Qinghai Province, restrains to probe the relationship of the deposits to the regional tectonic evolution. This paper documents the fission track method used to determine the ages of gold ore deposits in eastern Kunlun Mountains and considers the implication for the origin of the *** Kunlun Mountains is the northern part of the Qinghai—Tibet Plateau and is of three deep\|seated fault belts in about EW extension. This work mainly includes three gold ore districts. All of them, in the north of Mid\|Kunlun fault belt, belong to northern part of eastern Kunlun Mountains. The Yanjingou district, with geographical coordinate 96°00’E and 36°10’N, is located 60 km north of Hongqigou district . Both of them are large, typical tectonoalteration gold deposits and were formed in similar geological setting. Hongshuihe ore district is located 50 km east of Yanjingou district and includes tectonoalteration and magmatic cryptoexplosive gold deposits. Outcroped strata are dominantly Jinshuikou Group metamorphic rocks of Lower Proterozoic erathem. The occurrence area of igneous rocks, especially granitoid, accounts for about 90% in first two districts and become less in Hongshuihe district. The gold deposits occur in NW\|striking fault belts. The Rb\|Sr isochron age and K\|Ar isotopic age of Moyite relevant to the gold mineralization are respectively 2.8 2.Ma and 2.7 1Ma. Rb\|Sr dating of diorite porphyrite is 2.9 09Ma. Sericite selected from Yanjingou orebody has 2.2.9Ma K\|Ar age. The ore in Hongqigou district has 197Ma K\|Ar age and 2.0Ma model age of Pb isotope of galena.

关键词： mineralization age thermal event fission track thermochron ology fission track analysis eastern Kunlun Mountains

Orbit determination and prediction accuracy analysis for a regional tracking network

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Science china(physics,Mechanics & Astronomy) 2010年第6期53卷 1130-1138页

作者： ZHOU ShanShi 1,2.3 ,HU XiaoGong 1 & WU Bin 1 1 Shanghai Astronomical Observatory,chinese academy of sciences,Shanghai 2.0030,china 2.Graduate University of chinese academy of sciences,beijing 100049,china 3 Research Center of GNSS,Wuhan 430079,china Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai China Graduate University of chinese academy of sciences Beijing China Research Center of GNSS Wuhan China

china's COMPASS satellite navigation system relies on a regional tracking network to provide navigation services. Limited by its geographic border,the regional network is able to cover only 30% of the medium-earth-orbits(MEO). Accuracy of determined and predicted orbits is not able to satisfy system requirements if the tracking data processing strategy for global tracking network processing is used for the regional network. Two major error sources for orbital prediction are accuracy of initial orbital elements and dynamical modeling. To achieve better prediction accuracy,we propose a two-step orbit determination and prediction strategy. For step 1,only solar radiation pressure(SRP) parameters are estimated along with the orbital elements and other parameters; for step 2.all parameters are estimated but the SRP parameters are tightly constrained to their step 1 estimates. Experimenting with data from a regional GPS network,we conclude for orbital prediction using the proposed two-step strategy,the average user range error(URE) for 2.-h prediction arcs is better than 0.6 m.

关键词： orbit determination and prediction regional tracking network URE

A first-principles investigation into the hydrogen bond interaction in β-HMX

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Science china(physics,Mechanics & Astronomy) 2010年第6期53卷 1080-1085页

作者： CHEN Fang 1 ,ZHANG Hong 1,2.ZHAO Feng 3 ,MENG ChuanMin 3 & CHENG XinLu 1 1 institute of Atomic and Molecular physics,Sichuan University,Chengdu 610065,{2. 2.School of Physical Science and Technology,Sichuan University,Chengdu 610065,{2. 3 laboratory for Shock Wave and Detonation physics Research,Southwest institute of Fluid physics,{2. academy of Engineering physics,Mianyang 62.900,{2. institute of Atomic and Molecular physics Sichuan University Chengdu China School of Physical Science and Technology Sichuan University Chengdu China laboratory for Shock Wave and Detonation physics Research Southwest Institute of Fluid Physics China Academy of Engineering Physics Mianyang China

A theoretical study of structural and electronic properties of β-HMX crystal is performed using density-functional theory(DFT). The total density of states(TDOS) is presented. The atomic orbit projected density of state(PDOS) from the p-type orbit of C,N,O and the s-type orbit of H is discussed. The study by analyzing the PDOS shows that the structure of β-HMX crystal possesses C-H···O intra- and inter-molecular hydrogen-bonding. There exists a hydrogen bonding between H5 -1s and O12.-2. orbits,between H19 -1s and O2. -2. orbits of intra molecules,and between H19 -1s and O2. -2. orbits of inter molecules. The Mulliken population analysis is also made.

关键词： structural property hydrogen bond β-HMX population analysis