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Investigation into the rotational bands of ^(185)Pt with the particle-rotor model

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Science china(physics,Mechanics & Astronomy) 2011年第S1期54卷 114-118页

作者： LI GuangShun1,2, ZHOU XiaoHong1,2, ZHANG ShuangQuan3. ZHANG YuHu1 & MENG Jie3.1 institute of Modern physics, chinese academy of sciences, Lanzhou 73.000,{3. 2 Graduate University of chinese academy of sciences, beijing 100049,{3. 3.School of physics and SK Laboratory of Nuclear physics & Technology, Peking University, beijing 100871,{3. institute of Modern physics Chinese Academy of Sciences Lanzhou China Graduate University of chinese academy of sciences Beijing China School of physics and SK Laboratory of Nuclear physics & Technology Peking University Beijing China

Theoretical calculations have been performed for the ν9/2+[624](i13.2) and ν7/2-[503.(f7/2) bands of 185Pt in the framework of particle-rotor model. The band properties of signature splitting and configuration mixing have been analyzed. The level energy and signature splitting before the band crossing can be well interpreted by introducing triaxiality. The positive-parity yrast band is pro posed to be dominated by the ν9/2+[624](i13.2) component, while the negative-parity band shows strong mixing of ν7/2-[503.(f7/2) and ν9/2-[505](h9/2) configurations.

关键词： high-spin states particle-rotor model signature splitting configuration mixing

Exploration of combined adjustment laws about IGV,stator and rotational speed in off-design conditions in an axial compressor

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中国科学：技术科学英文版 2010年第4期53卷 969-975页

作者： HU YanMing1,2 & NIE ChaoQun1 1 Key Laboratory of Advanced energy and Power Technology,institute of Engineeting Thermophysics,{3. academy of Science,beijing 100190,china 2 Graduate School of chinese academy of sciences,beijing 100190,china Key Laboratory of Advanced energy and Power Technology Institute of Engineeting Thermophysics Chinese Academy of Science Beijing China Graduate School of chinese academy of sciences Beijing China

Experimental investigations are performed in a three-stage low-speed axial compressor with variable inlet guide vanes(IGV) and adjustable *** characteristics of the compressor,especially the efficiency and stall margin,are analyzed in design and off-design operation conditions by adjusting stagger angles of IGV and stators as well as changing the rotational *** experimental results show that the off-design performance of the multistage axial compressor is improved by restaggering of IGV and stators related to rotational *** the background of engineering applications,digital signal processing(DSP) technique is used to realize online adjustment of stagger angles according to the corresponding relations between incidence angles of rotor and rotational speed.

关键词： axial compressor IGV surge DSP techniques off-design

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 {3.,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

Progress in multi-waveband observations of supernova remnants

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Progress in Natural Science:Materials International 2008年第9期18卷 1057-1062页

作者： Xuejuan Yang a,b, Fangjun Lua, Wenwu Tian c,d,* a Particle Astrophysics Center, institute of high energy physics, chinese academy of sciences, {3. 100049, china b Department of Astronomy, {3. Normal University, {3. 100875, china c National Astronomical Observatories, chinese academy of sciences, 20A Datun Road, Chaoyang District, CAS, {3. 100012, china d Department of physics & Astronomy, University of Calgary, Alberta, Canada T2N 1N4 Particle Astrophysics Center Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Department of Astronomy Beijing Normal University Beijing 100875 China National Astronomical Observatories Chinese Academy of Sciences 20A Datun Road Chaoyang District CAS Beijing 100012 China Department of physics & Astronomy University of Calgary Alberta Canada T2N 1N4

The development of observational techniques has enriched our knowledge of supernova remnants. In this paper, we review the main progresses in the last decade, including new discoveries of supernova remnants and the associated (rare type of) pulsars, nucleosynthesis, the interaction between supernova remnants and molecular clouds, dust in the supernova remnants, shock physics, and cosmic ray accelerations.

关键词： Supernova remnant Observations

Evolution of desertification in a two-dimensional energy balance model coupled with thermodynamics and dynamics

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Science china Earth sciences 2010年第11期53卷 1726-1733页

作者： CHAO JiPing1,2 & LI YaoKun3.4 1National Marine Environmental Forecasting Center, beijing 100081, china 2First institute of Oceanography, State Oceanic Administration, Qingdao 266061, china 3.tate Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics, institute of Atmospheric physics, chinese academy of sciences, beijing 100029, china 4Graduate University of chinese academy of sciences, beijing 100049, china National Marine Environmental Forecasting Center Beijing China First institute of Oceanography State Oceanic Administration Qingdao China State Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China

The relationship between desert evolution and change in albedo has been investigated quasi-analytically using a zonal mean two-dimensional energy balance model which considers the radiation transmission process due to thermodynamics and bound- ary layer movement caused by kinetics. A climate state including temperature, zonal wind, meridional wind and vertical wind can be simulated according to the current zonal distribution of albedo. Given desert distribution, characterized by the value and distribution of albedo, the response of climate on albedo has been studied to analyze the evolution of desert climate. One significant result is that the simple model can reproduce mean meridional circulation. Another result indicates that climate corresponds to two equilibria. This happens when the junction temperature between vegetation and desert is higher than a certain critical value. As for the first equilibrium, the desert belt is predicted to move southward in the northern hemisphere with the increasing values of albedo, which corresponds to the current trend of climate change. For the second equilibrium, vegetation will expand northward with increasing values of albedo, which would indicate a narrowing of the desert belt. In order to determine if the two equilibria exist, new physical models are needed.

关键词： two-dimensional energy balance model desertification two equilibria

Quantifying the effectiveness of SiO_2/Au light trapping nanoshells for thin film poly-Si solar cells

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Science china(Technological sciences) 2010年第8期53卷 2228-2231页

作者： BAI YiMing 1 ,WANG Jun 2 ,CHEN NuoFu 1,3.,YAO JianXi 1 ,YIN ZhiGang 3.,ZHANG Han 3., ZHANG XingWang 3.,HUANG TianMao 3.,WANG YanShuo 3.&YANG XiaoLi 3.1School of Renewable energy Engineering,North china Electric Power University,beijing 102206,{3. 2 National Engineering Research Center for Optoelectronic Devices,institute of Semiconductors, chinese academy of sciences,PO Box 912,beijing 100083.{3. 3.Key Laboratory of Semiconductor Materials Science,institute of Semiconductors, chinese academy of sciences,PO Box 912,beijing 100083.{3. School of Renewable energy Engineering North China Electric Power University Beijing China National Engineering Research Center for Optoelectronic Devices Institute of Semiconductors Chinese Academy of Sciences Beijing China Key Laboratory of Semiconductor Materials Science Institute of Semiconductors Chinese Academy of Sciences Beijing China

In order to enhance light absorption of thin film poly-crystalline silicon(TF poly-Si)solar cells over a broad spectral range, and quantify the effectiveness of nanoshell light trapping structure over the full solar spectrum in theory,the effective photon trapping flux(EPTF)and effective photon trapping efficiency(EPTE)were firstly proposed by considering both the external quantum efficiency of TF poly-Si solar cell and scattering properties of light trapping *** EPTF,EPTE and scattering spectrum exhibit different behaviors depending on the geometric size and density of nanoshells that form the light trapping *** an optimum size and density of SiO2/Au nanoshell light trapping layer,the EPTE could reach up to 40%due to the enhancement of light trapping over a broad spectral range,especially from 500 to 800 nm.

关键词： thin film poly-crystalline silicon surface plasmons SiO2/Au nanoshell

BOUNDARY FEEDBACK STABILIZATION OF NONUNIFORM TIMOSHENKO BEAM WITH A TIPLOAD

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chinese Annals of Mathematics,Series B 2001年第4期22卷 485-494页

作者： YAN QINGXU, FENG DEXING institute of Systems Science, academy of Mathematics and Systems Science, chinese academy of sciences, {3. 100080, china. institute of Systems Science, academy of Mathematics and Systems Science, chinese academy of sciences, Be institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China

The boundary stabilization problem of a Timoshenko beam attached with a mass at one end is studied. First, with linear boundary force feedback and moment control simultaneously at the end attached with the load, the energy corresponding to the closed loop system is proven to be exponentially convergent to zero as time t →∞. Then, some counterexamples are given to show that, in other casest the corresponding closed loop system is, in general, not stable asymtotically, let alone exponentially.

关键词： Timoshenko beam Boundary feedback control C0 semigroups Exponential stability Multiplier method

Primary scientific results of Chang'E-1 lunar mission

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Science china Earth sciences 2010年第11期53卷 1565-1581页

作者： OUYANG ZiYuan1,2, LI ChunLai1, ZOU YongLiao1, ZHANG HongBo1, Lü Chang1, LIU JianZhong1, LIU JianJun1, ZUO Wei1, SU Yan1, WEN WeiBin1, BIAN Wei1, ZHAO BaoChang3. WANG JianYu4, YANG JianFeng3. CHANG Jin5, WANG HuanYu6, ZHANG XiaoHui7, WANG ShiJin7, WANG Min1, REN Xin1, MU LingLi1, KONG DeQing1, WANG XiaoQian1, WANG Fang1, GENG Liang1, ZHANG ZhouBin1, ZHENG Lei1, ZHU XinYing1, ZHENG YongChun1, LI JunDuo1, ZOU XiaoDuan1, XU Chun1, SHI ShuoBiao1, GAO YiFei1 & GAO GuanNan1 1 National Astronomical Observatories, chinese academy of sciences, beijing 100012, china 2 {3. of Geochemistry, chinese academy of sciences, Guiyang 550002, china 3.Xi’an {3. of Optics and Precision Mechanics, chinese academy of sciences, Xi’an 710119, china 4 Shanghai {3. of Technical physics, chinese academy of sciences, Shanghai 200083. china 5 Purple Mountain Observatory, chinese academy of sciences, Nanjing 210008, china 6 institute of high energy physics, chinese academy of sciences, beijing 100049, china 7 Center for Space Science and Applied Research, chinese academy of sciences, beijing 100190, china National Astronomical Observatories Chinese Academy of Sciences Beijing China institute of Geochemistry Chinese Academy of Sciences Guiyang China Xi’an institute of Optics and Precision Mechanics Chinese Academy of Sciences Xi’an China Shanghai institute of Technical physics Chinese Academy of Sciences Shanghai China Purple Mountain Observatory Chinese Academy of Sciences Nanjing China institute of high energy {3. Chinese Academy of Sciences Beijing China Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China

The strategic plan for the development of the unmanned chinese Lunar Exploration Program is characterized by three distinct stages: "orbiting around", "landing on" and "returning from" the Moon. The first chinese lunar probe, Chang'E-1, which was successfully launched on October 24th, 2007 at Xichang Satellite Launch Center, and guided to crash on the Moon on March 1st, 2009, at 52.3.°E, 1.50°S, in the north of Mare Fecunditatis, is the first step towards the "orbiting around" stage. The Chang'E-1 mission lasted 495 days, exceeding the expected life-span by about four months. A total of 1.3. TB raw data was received from Chang'E-1. It was then processed into 4 TB scientific data products at various levels. Many scientific results have been obtained by analyzing these data, including especially the "global lunar image from the first chinese lunar explora- tion mission". All scientific goals of Chang'E-1 have been achieved. It provides much useful materials for further advances of lunar {3. and planetary chemistry. Meanwhile, these results will serve as a firm basis for future chinese lunar missions.

关键词： lunar orbiter Chang’E-1 scientific data results

Spectroscopic evidence for triplet excitation energy transfer among carotenoids in the LH2 complex from photosynthetic bacterium Rhodopseudomonas palustris

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Science china Chemistry 2004年第1期47卷 80-90页

作者： FENG Juan, WANG Qian, ZHANG Xujia, HUANG Youguo, Al Xicheng, ZHANG Xingkang & ZHANG JianpingState Key Laboratory for Structural Chemistry of Unstable and Stable Species, institute of Chemistry, chinese academy of sciences, beijing 100080,{3. National Laboratory of Biomacromolecules, institute of Biophysics, chinese academy of sciences, beijing 100101,{3. State Key Laboratory for Structural Chemistry of Unstable and Stable Species institute of Chemistry Chinese Academy of Sciences Beijing China National Laboratory of Biomacromolecules institute of Biophysics Chinese Academy of Sciences Beijing China

The LH2 complex from Rhodopsudomonas (Rps.) palustris is unique in the heterogeneous carotenoid compositions. The dynamics of triplet excited state Carotenoids (3.ar* has been investigated by means of sub-microsecond time-resolved absorption spectroscopy both at physiological temperature (295 K) and at cryogenic temperature (77K). Broad and asymmetric T n ←T 1 transient absorption was observed at room temperature following the photo-excitation of Car at 53. nm, which suggests the contribution from various carotenoid compositions having different numbers of conjugated C=C double bonds (Nc=c). The triplet absorption bands of different carotenoids, which superimposed at room temperature, could be clearly distinguished upon decreasing the temperature down to 77 K. At room temperature the shorter-wavelength side of the main Tn04T1 absorption band decayed rapidly to reach a spectral equilibration with a characteristic time constant of ∽1 μs, the same spectral dynamics, however, was not observed at 77 K. The aforementioned spectral dynamics can be explained in terms of the triplet-excitation transfer among heterogeneous carotenoid compositions. Global spectral analysis was applied to the time-resolved spectra at room temperature, which revealed two spectral components peaked at 545 and 565 nm, and assignable to the Tn04 T1 absorption of Cars with Nc=c=11 and Nc=c=13. respectively. Surprisingly, the decay time constant of a shorter-conjugated Car, i.e. 0.72 ?s (aerobic) and 1.3. ?s (anaerobic), is smaller than that of a longer-conjugated Car, i.e. 2.12 us (aerobic) and 3.75 ?s (anaerobic), which is contradictory to the general rule of carotenoids and relative polyenes. The results are explained in terms of triplet-excitation transfer among different types of Cars. It is postulated that two Cars with different conjugation lengths coexist in an α, β-subunit in the LH2 complex.

关键词： purple photosynthetic bacteria, carotenoid, excited-state, time-resolved spectroscopy.