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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, {2. of Chemistry, chinese academy of sciences, beijing 100080, china National laboratory of Biomacromolecules, {2. of Biophysics, chinese academy of sciences, beijing 100101, china State key laboratory for Structural Chemistry of Unstable and Stable Species {2. 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 (3Car* has been investigated by means of sub-microsecond time-resolved absorption spectroscopy both at physiological temperature (2.5 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 532.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 1.36 ?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.

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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, {2. of high energy Physics, chinese academy of sciences, beijing 100049, china b Department of astronomy, beijing Normal University, beijing 100875, china c National astronomical Observatories, chinese academy of sciences, 2.A Datun Road, Chaoyang District, CAS, beijing 100012. china d Department of Physics & astronomy, University of Calgary, Alberta, Canada T2. 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

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A Novel Polymer Electrolyte Using In-situ Quanternization for All Solid-state Dye-sensitized Solar Cell

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复旦学报（自然科学版） 2007年第5期46卷 658-659页

作者： Wanchun Xiang1,2. Xiong Yin1,2. Xurui Xiao1, Yuan Lin1, Shibi Fang1(1.key laboratory of Photochemistry, {2. of Chemistry, chinese academy of sciences, beijing 100080, china 2.Graduate School of chinese academy of sciences, beijing 100049, china) institute of Chenmistry Chinese Academy of Science Key Laboratory of Photochemistry Chinese Academy of Science Beijing 100080

1 Introduction Dye-sensitized solar cells (DSSCs) with a mesoporous network of interconnected TiO2.nanocrystals have attracted wide-spread scientific and technological interest over the past decades due to its low cost and high energy conversion efficiency. Meantime, it also has been considered as potential alternative to conventional photovoltaic devices. In 2.01, Gratzel group constructed such kind of DSSC with the conversion efficiency of more than 11%[1]. But this system uses liquid electrolyte with...

关键词： in-situ quanternization reaction latent cross-linking precursor all solid-state electrolyte dye-sensitized solar cell

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MB_8^(2.) (M=Be,Mg,Ca,Sr,and Ba):Planar octacoordinate alkaline earth metal atoms enclosed by boron rings

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Science china Chemistry 2010年第8期53卷 1737-1745,1829-1832页

作者： PU ZhiFeng1,GE MaoFa1 & LI QianShu2.1State key laboratory for Structural Chemistry of Unstable and Stable Species {2. National laboratory for Molecular sciences (BNLMS) institute of Chemistry,chinese academy of sciences,{2. 100190,china 2.enter for Computational Quantum Chemistry,South china Normal University,Guangzhou 510631,china State key laboratory for Structural Chemistry of Unstable and Stable Species beijing National laboratory for Molecular {2. (BNLMS) institute of Chemistry Chinese Academy of Sciences Beijing China Center for Computational Quantum Chemistry South China Normal University Guangzhou China

Complexes involving planar octacoordinate alkaline earth metal atoms in the centers of eight-membered boron rings have been investigated by two density functional theory (DFT) ***82.with D8h symmetry is predicted to be stable,both geometrically and electronically,since a good match is achieved between the size of the central beryllium atom and the eight-membered boron *** contrast,the other alkaline earth metal atoms cannot be stabilized in the center of a planar eight-membered boron ring because of their large *** following the out-of-plane imaginary vibrational frequency,pyramidal C8v MgB82.,CaB82.,SrB82.,and BaB82.structures are *** presence of delocalized π and σ valence molecular orbitals in D8h BeB82.gives rise to aromaticity,which is reflected by the value of the nucleus-independent chemical *** D8h BeB82.structure is confirmed to be the global minimum on the potential energy surface.

关键词： density functional theory octacoordinate alkaline earth metal aromatic molecular orbital

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Anomalous magnetotransport in LaMn_(1-x)Te_xO_3

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Science china(Physics,Mechanics & astronomy) 2009年第7期52卷 987-992页

作者： TAN GuoTai1,2. CHEN ZhengHao3 & ZHANG XiaoZhong4,5 1 key laboratory of Beam Technology & Materials Modification of the Ministry of Education, {2. of Low energy Nuclear Physics, beijing Normal University, beijing 100875, china 2.beijing Radiation Center, beijing 100875, china 3 laboratory of Optical Physics, {2. of Physics,{12., beijing 100080, china 4 key laboratory of Advanced Materials of the Ministry of Education, Department of Materials Science and Engineering, Tsinghua University, beijing 100084, china 5 beijing National Center for Electron Microscopy, Tsinghua University, beijing 100084, china key laboratory of Beam Technology & Materials Modification of the Ministry of Education Institute of Low Energy Nuclear Physics Beijing Normal University Beijing China beijing Radiation Center Beijing China laboratory of Optical Physics Institute of Physics Chinese Academy of Sciences Beijing China key laboratory of Advanced Materials of the Ministry of Education Department of Materials Science and Engineering Tsinghua University Beijing China beijing National Center for Electron Microscopy Tsinghua University Beijing China

The LaMn1-xTexO3+δ (x=0.1, 0.2. 0.3) were synthesized using solid-state reaction method for the first time. X-ray photoemission spectrum (XPS) shows that in the samples the Te ions have a valence of Te4+, and Mn3+ ions are partly converted into Mn2. and Mn4+ due to the excess oxygen and Te doping. The magnetotransport associated with Mn2., Mn3+ and Mn4+ was investigated. The experimental results show that the samples are insulator at 0 T when the amount of Mn3+ is much larger or less than the sum of Mn2. and Mn4+; by contrast, the samples display metal to insulator transition with increasing temperature when the amount of Mn3+ is close to the sum of Mn2. and Mn4+. These anomalous magnetotransport behaviors were analyzed in the frame of the double-exchange (DE) mechanism.

关键词： colossal magnetoresistance La-Te-Mn-O magnetotransport

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Multiple time scale evaluation of the energy balance during the maize growing season,and a new reason for energy imbalance

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Science china Earth sciences 2009年第1期52卷 108-117页

作者： GUO JianXia1,2.BIAN LinGen3 & DAI YongJiu2.1 Meteorological Observation Center of china Meteorological Administration,beijing 100081,{2. 2.State key laboratory of Remote Sensing Science,School of Geography and Remote Sensing Science,beijing Normal University,beijing 100875,{2. 3 chinese academy of Meteorological sciences,beijing 100081,{2. Meteorological Observation Center of china Meteorological Administration Beijing China State key laboratory of Remote Sensing Science School of Geography and Remote Sensing Science Beijing Normal University Beijing China chinese academy of Meteorological {2. Beijing China

energy imbalance is a common problem associated with the measurement of surface energy using the eddy covariance *** the evaluation of the energy balance,people usually pay more attention to the statistical result that the effective energy(the sum of sensible and latent heat) is systematically lower than the available energy(the difference of net radiation and ground heat flux).However,little attention has been paid to the existence of the reversed situation when the effective energy is larger than the available energy or their contribution to the overall energy closure *** this paper,based on the analysis of the energy balance on multiple time scales across the maize growth season,we conclude that the non-synchronization of energy components is the main reason for the existence of the reversed *** shifting the phase of the effective energy components half an hour ahead,the rates of energy closure over all time scales are improved and dramatically reduce the number of the half-hourly samples when the energy ratio exceeds 1 or is below *** to the characteristics of the energy distribution and transformation over multiple time scales,latent heat is always the main type of energy cost,and the residual of the energy balance increases with the growth of the maize plant surpassing the sensible heat for seventy *** is suggested that the heat storage and photosynthetic energy play an important role in the energy balance during the growing period of maize.

关键词： maize energy balance multiple time scale energy hysteresis

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An efficient quantum secret sharing protocol with orthogonal product states

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Science china(Physics,Mechanics & astronomy) 2007年第3期50卷 331-338页

作者： YANG YuGuang1,2. WEN QiaoYan3 & ZHU FuChen4 1 School of Computer, beijing University of Technology, beijing 10002.,{2. 2.State key laboratory of Information Security, Graduate University of chinese academy of sciences, beijing 10002.,{2. 3 School of Science, beijing University of Posts and Telecommunications, beijing 100876,{2. 4 National key laboratory for Modern Communications, Chengdu 610041,{2. School of Computer Beijing University of Technology Beijing China State key laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing China School of Science Beijing University of Posts and Telecommunications Beijing China National key laboratory for Modern Communications Chengdu China

An efficient quantum secret sharing protocol with orthogonal product states in the 33 Hilbert space is presented. The particles in the orthogonal product states form two particle sequences. One sequence is sent to Bob and the other is sent to Charlie after rearranging the particle orders. With the help of Alice, Bob and Charlie make the corresponding local measurement to obtain the information of the or- thogonal product states prepared. This protocol has many distinct features such as great capacity and high efficiency.

关键词： quantum secret sharing orthogonal product state orthogonal measurement

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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 730000,{2. 2.Graduate University of chinese academy of sciences, beijing 100049,{2. 3 School of Physics and SK laboratory of Nuclear Physics & Technology, Peking University, beijing 100871,{2. 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.[62.](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.[62.](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

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Electron dynamics in collisionless magnetic reconnection with a PIC simulation

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chinese Science Bulletin 2009年第3期54卷 456-460页

作者： GUO Jun1,2.1 School of Mathematics and Physics, Qingdao University of Science and Technology, Qingdao 2.6042. china 2.State key {2. of Space Weather, chinese academy of sciences, beijing 100080, china School of Mathematics and Physics Qingdao University of Science and Technology Qingdao China State key laboratory of Space Weather Chinese Academy of Sciences Beijing China

Two-dimensional particle-in-cell (PIC) simulation is used to investigate electron dynamics in colli- sionless magnetic reconnection, and the proton/electron mass ratio is taken to be mi /me = 2.6. The results show that the presence of a strong initial guide field will change the direction of the electron flow. The electron density cavities and the parallel electric field can be found in the electron inflow re- gion along the separatrix, and the electron inflow and density cavities only appear in the second and fourth quadrants. What is different from the results with a smaller mass ratio is that new structures appear in the diffusion region near the X line: (1) Narrow regions of density enhancement and density cavities can be found synchronously in this region; and (2. corresponding to the electron density changes near the X line, the strong parallel electric fields are found to occur in the first and third quadrants. These electric fields perhaps play a more important role in acceleration and heating electrons than those fields located in the density cavities.

关键词： PIC模仿磁链接导向场电子动力学

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An integrated turbocharger design approach to improve engine performance

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Science china(Technological sciences) 2010年第1期53卷 69-74页

作者： ZHANG YangJun1,CHEN Tao1,ZHUGE WeiLin1,ZHANG ShuYong2.& XU JianZhong3 1 State key laboratory of Automotive Safety and {2.,Tsinghua University,beijing 100084,china 2.National key laboratory of Diesel Engine Turbocharging Technology,P.O.B.2.,Datong 037036,china 3 institute of Engineering Thermophysics,chinese academy of sciences,beijing 100190,china State key laboratory of Automotive Safety and {2. Tsinghua University Beijing China National key laboratory of Diesel Engine Turbocharging Technology Datong China institute of Engineering Thermophysics Chinese Academy of Sciences Beijing China

Turbocharging technology is today considered as a promising way for internal combustion engine energy saving and CO2.*** design is a major challenge for turbocharged engine performance *** turbocharger designer must draw upon the information of engine operation conditions,and an appropriate link between the engine requirements and design features must be carefully developed to generate the most suitable design *** objective of this research is to develop a turbocharger design approach for better turbocharger matching to an internal combustion *** development of the approach is based on the concept of turbocharger design and interaction links between engine cycle requirements and design parameter values.A turbocharger through flow model is then used to generate the design *** integrated method has been applied with success to a gasoline engine turbocharger assembly.

关键词： turbocharger design internal combustion engine integrated method through flow model

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