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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, Institute of Chemistry, chinese academy of sciences, Beijing 100080, china National Laboratory of Biomacromolecules, Institute of Biophysics, chinese academy of sciences, Beijing 100101, china 1. State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences 100080 Beijing China 2. National Laboratory of Biomacromolecules Institute of Biophysics Chinese Academy of Sciences 100101 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.

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Urban effects and summer thunderstorms in a tropical cyclone affected situation over Guangzhou city

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science china Earth sciences 2007年第12期50卷 1867-1876页

作者： MENG WeiGuang1,3.YAN JingHua1 & HU HaiBo2 1 Institute of Tropical and Marine Meteorology,chinese Meteorological Administration(CMA),Guangzhou 510080,china 2 Institute of Urban Meteorology,CMA,Beijing 100089,china 3.State Key Laboratory of Severe Weather,chinese academy of Meteorological sciences,Beijing 100081,china 1. Institute of Tropical and Marine Meteorology Chinese Meteorological Administration (CMA) Guangzhou 510080 China 3. State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China 2. Institute of Urban Meteorology CMA Beijing 100089 China

With data mainly from Guangzhou mesonet Automatic Weather Stations(AWS),Guangzhou Doppler Radar and satellite TBB data,characteristics and evolution of the urban heat island(UHI) over Guang-zhou City were analyzed in a tropical cyclone affected situation for early August *** particular,two thunderstorms occurring during this period respectively at the night of 4 August and in the afternoon of 7 August were investigated to study the relationships between the development of thunderstorms and the *** showed that two thunderstorms were associated with the UHI *** induced local air convergence and initiated the thunderstorm *** cases showed a general agreement in time and space for the locations of maximum UHI,convergence,convection,and *** was found to be more favorable to developing in time periods and locations with stronger intensity of *** also showed that,due to the urban effects,both thunderstorms got strengthened when moving over Guangzhou City,with maximum radar echoes observed right over the urban area and precipitation located within the *** these features reveal that two thunderstorms were urban-induced storms.

关键词： summer thunderstorms, urban heat islands (UHI), urban effects, tropical cyclone

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A unified dynamic model for locomotion and manipulation of a snake-like robot based on differential geometry

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science china(Information sciences) 2011年第2期54卷 318-333页

作者： WANG ZhiFeng1,3. MA ShuGen1,2, LI Bin1 & WANG YueChao1 1State Key Laboratory of Robotics, Shenyang Institute of Automation, chinese academy of sciences, Shenyang 110016, china 2Department of Robotics, Ritsumeikan University, Shiga-ken 525-8577, Japan 3.raduate University of chinese academy of sciences, Beijing 10003., china 1. State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Shenyang 110016 China3. Graduate University of Chinese Academy of Sciences Beijing 100039 China2. Department of Robotics Ritsumeikan University Shiga-ken 525-8577 Japan

A snake-like robot, whose body is a seried-wound articulated mechanism, can move in various environments. In addition, when one end is fixed on a base, the robot can manipulate objects. A method of dynamic modeling for locomotion and manipulation of the snake-like robot is developed in order to unify the dynamic equations of two states. The transformation from locomotion to manipulation is a mechanism reconfiguration, that is, the robot in locomotion has not a fixed base, but it in manipulation has one. First, a virtual structure method unifies the two states in mechanism (e.g., an embedding in the configuration space); second, the product-of-exponentials formula describes the kinematics; third, the dynamics of locomotion and manipulation are established in a Riemannian manifold; finally, based on the analysis of the dynamic model, the dynamics of manipulation can be directly degenerated from those of locomotion, and this degeneration relation is proved through using the Gauss equations. In the differential geometry formulation, this method realizes the unification of the dynamics of locomotion and manipulation. According to a geometrical point of view, the unified dynamic model for locomotion and manipulation is considered as a submanifold problem endowed with geometric meaning. In addition, the unified model offers an insight into the dynamics of the snake-like robot beyond the dynamic model separately established for locomotion or manipulation.

关键词： snake-like robot dynamics unified model differential geometry locomotion manipulation

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A Simulator for Producing of High Flux Atomic Oxygen Beam by Using ECR Plasma Source

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Journal of Materials science & Technology 2004年第6期20卷 759-762页

作者： Shuwang DUO, Meishuan LI and Yaming ZHANGShenyang National Laboratory for Materials science, Institute of Metal Research, chinese academy of sciences, Shenyang 110016, china Shenyang Natl. Lab. for Mat. Sci. Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110016 China

In order to study the atomic oxygen corrosion of spacecraft materials in low earth orbit environment, an atomic oxygen simulator was established. In the simulator, a 2.45 GHz microwave source with maximum power of 600 W was launched into the circular cavity to generate ECR (electron cyclotron resonance) plasma. The oxygen ion beam moved onto a negatively biased Mo plate under the condition of symmetry magnetic mirror field confine, then was neutralized and reflected to form oxygen atom beam. The properties of plasma density, electron temperature, plasma space potential and ion incident energy were characterized. The atomic oxygen beam flux was calibrated by measuring the mass loss rate of Kapton during the atomic oxygen exposure. The test results show that the atomic oxygen beam with flux of 1016-1017 atoms-cm-2·s-1 and energy of 5-3. eV and a cross section of φ80 mm could be obtained under the operating pressure of 10-1-10-3.Pa. Such a high flux source can provide accelerated simulation tests of materials and coatings for space {3.s.

关键词： Atomic oxygen Low earth orbit space environment ECR plasma Microwave

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SHRIMP dating of the Bangong Lake SSZ-type ophiolite: Constraints on the closure time of ocean in the Bangong Lake-Nujiang River,northwestern Tibet

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chinese science Bulletin 2007年第7期52卷 936-941页

作者： SHI RenDeng1,2 1 School of Earth and space sciences, University of science and Technology of{3., Hefei 23.026,{3. 2 Institute of Geology, chinese academy of Geological sciences, Beijing 10003.,{3. (email: shird@***) School of Earth and space sciences University of Science and Technology ofChina Hefei 230026 China

The Bangong Lake ophiolite is located in the westernmost part of the Bangong Lake-Nujiang River suture zone. It is a tectonic mélange consisting of numerous individual blocks of peridotite, pillowed and massive lavas and mafic dykes with SSZ-type ophiolitic geochemical affinity formed at the end of a Wilson circle. The SHRIMP U-Pb ages of the co-magmatic zircon domains from one gabbroic dyke (Sample 01Y-155) range from 162.5±8.6 Ma to 177.1±1.4 Ma with an average of 167.0±1.4 Ma (n = 12, MSWD = 1.2), suggesting that the subduction of the Bangong Lake Neo-Tethyan Ocean started before the Middle Jurassic. It is inferred that the tectonic transform from spreading to subduction of the Neo-Tethyan Ocean began before the Middle Jurassic in the Bangong Lake area.

关键词：西藏班公湖怒江缝合带古海洋闭合时期 SSZ型蛇绿岩 SHRIMP 测年

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Uncertainty in magnetic activity indices

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science china(Technological sciences) 2008年第10期51卷 1659-1664页

作者： XU WenYao Institute of Geology and Geophysics, chinese academy of sciences, Beijing 100029, china Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Magnetic activity indices are widely used in theoretical studies of solar-terrestrial coupling and space weather prediction. However, the indices suffer from various uncertainties, which limit their application and even mislead to incorrect conclu-sion. In this paper we analyze three most popular indices, Kp, AE and Dst. Three categories of uncertainties in magnetic indices are discussed: "data uncertainty" originating from inadequate data processing, "station uncertainty" caused by in-complete station covering, and "physical uncertainty" stemming from unclear physical mechanism. A comparison between magnetic disturbances and related indices indicate that the residual Sq will cause an uncertainty of 1―2 in K meas-urement, the uncertainty in saturated AE is as much as 50%, and the uncertainty in Dst index caused by the partial ring currents is about a half of the partial ring cur-rent.

关键词： magnetic activity indices Kp AE Dst solar-terrestrial coupling space weather

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A method to predict amplitude and date of maximum sunspot number

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chinese science Bulletin 2000年第14期45卷 1287-1290页

作者： HAN YanbenBeijing Astronomical Observatory, chinese academy of sciences, National Astronomical Observatories, chinese academy of sciences, Beijing 100012, china Beijing Astronomical Observatory Chinese Academy of Sciences National Astronomical Observatories Chinese Academy of Sciences Beijing China

A method to predict the amplitude and date of the maximum sunspot number is introduced. The regression analysis of the relationship between the variation rate of monthly sunspot numbers in the initial stage of solar cycles and both of the maximum and the time-length of ascending period of the cycle showed that they are closely correlative. In general, the maximum will be larger and the ascending period will be shorter when the rate is larger. The rate of sunspot numbers in the initial 2 years of the 23.d cycle is thus analyzed based on these grounds and the maximum of the cycle is predicted. For the smoothed monthly sunspot numbers, the maximum will be about 13..2 ±18.8 and the time-length of ascending period will be about 3.3. ±0.42 years, that is to say, the maximum will appear around the spring of the year 2000. For the mean monthly ones, the maximum will be near 170.1±22.9 and the time-length of ascending period will be about 3.42 ±0.46 years, that is to say, the appearing date of the maximum

关键词： solar activity prediction sunspot number 23.d solar cycle.

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Study of Product Quality Information and Construction of Its Decision-Making Support System and Measures to Improve People's Quality Concept

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厦门大学学报（自然科学版） 2002年第S1期41卷 234-235页

作者： RUAN Jin-yuan 1, SUN Shu-tao 2, YU Xin-qi 2, RUAN Xin 3.(1. Ordance Institute of general Equipment Department, Shijiazhuang 05 0000, china 2. Graduate School of chinese Academic of {3., Beijing 100042, china 3. East china University of {3. and Technology, Shanghai 20023., china 4. Meterology Bureau of Hebei Province, Shijiazhuang 050021, china)

The 21th century is a "quality century". Facing the s evere challenge about quality, all the developed industry countries attach impor tance to the research and education about quality project. With the deepening of the reform of china and it’s joining to WTO, many industries and enterprises wi ll be confronted with severe challenge while being offered the opportunity to wa lk up to the world. The arrival of knowledge economy and web time has provided t he space for the innovation on enterprise management. It has also provided new m ethod and model for enterprise management, that is online management based on th e internet. The online management use an enterprise model including the goal of the enterprise and the scheme to carry out it to represent the whole operational of all the work. The online management is constructed on the integration of exp ert system, database, software and other technical models. How to scientifically manage the entire system of product, precisely master the condition of quantity and quality and analyze the rules of the change of produc t quality in order to carry out the overall control of quality, guarantee the go od condition of product as well as improve product quality and prolong it’s se rvice life was discussed in this thesis. Based on the above research the thesis also discussed how to develop the study on product quality information and const ruct it’s decision making support system. The concrete measures to improve peopl e’s concept of quality are also raised. Based on the type analysis, scientific management of product quality information should start from dynamic information of quality, instruction information as we ll as the information about the use, maintain, management and conservation of pr oduct, and induce them and further propose a design scheme of feedback system on product quality information, and then set up the blueprint of the information s ystem of product quality. This thesis included 7 chapters:*** type of qua

关键词： product guality information decision-making sup port system of management of guality information people’s guality concept

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HOPF BIFURCATION AND CHAOS OF FINANCIAL SYSTEM ON CONDITION OF SPECIFIC COMBINATION OF PARAMETERS

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Journal of Systems science & Complexity 2008年第2期21卷 250-259页

作者： Junhai MA Yaqiang CUI Lixia LIU Management School of Tianjin University Tianjin 300072 China Tianjin University of Finance and Economics Tianjin 300222 China

This paper studies the global bifurcation and Hopf bifurcation of one kind of complicated financial system with different parameter combinations. Conditions on which bifurcation happens, and the critical system structure when the system transforms from one kind of topological structure to another are studied as well. The criterion for identifying Hopf bifurcation under different parameter combinations is also given. The chaotic character of this system under quasi-periodic force is finally studied. The bifurcation structure graphs are given when two parameters of the combination are fixed while the other parameter varies. The presence and stability of 2 and 3.dimensional torus bifurcation are studied. All of the Lyapunov exponents of the system with different bifurcation parameters and routes leading the system to chaos with different parameter combinations are studied. It is of important theoretical and practical meaning to probe the intrinsic mechanism of such continuous complicated financial system and to find the macro control policies for such kind of system.

关键词： Chaos complicated financial system equilibrium "drift" Hopf bifurcation strange non- chaotic attractor.

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Relationship between the Asian-Pacific oscillation and the tropical cyclone frequency in the western North Pacific

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science china Earth sciences 2008年第3期51卷 380-385页

作者： ZHOU BoTao1, CUI Xuan2 & ZHAO Ping3.1 Laboratory for Climate Studies, National Climate Center, china Meteorological Administration, Beijing 100081, china 2 National Meteorological Center, china Meteorological Administration, Beijing 100081, china 3.chinese academy of Meteorological sciences, china Meteorological Administration, Beijing 100081, china 1. Laboratory for Climate Studies National Climate Center China Meteorological Administration Beijing 100081 China 2. National Meteorological Center China Meteorological Administration Beijing 100081 China 3. chinese academy of Meteorological sciences China Meteorological Administration Beijing 100081 China

The relationship between the Asian-Pacific oscillation (APO) and the tropical cyclone frequency over the western North Pacific (WNP) in summer is preliminarily investigated through an analysis of ob- served data. The result has shown clearly that APO is significantly and positively correlated to the tropical cyclone frequency in the WNP. If APO is above (below) the normal in summer, more (less) tropical cyclones will tend to appear in the WNP. The present study also addresses the large-scale at- mospheric general circulation changes underlying the linkage between APO and the WNP tropical cy- clone frequency. It follows that a positive phase of summer APO is concurrent with weakened as well as northward and eastward located western Pacific subtropical high (WPSH), low-level convergence and high-level divergence, and reduced vertical zonal wind shear in the WNP, providing favorable envi- ronment for the tropical cyclone genesis, and thus more tropical cyclones will come into being, and vice versa.

关键词： Asian-Pacific oscillation western North Pacific tropical cyclone atmospheric circulation

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