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Metals Supported Water Monomers:the Bonding Nature Revisited

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Journal of Materials Science & Technology 2010年第2期26卷 97-105页

作者： Jibiao Li, Shenglong Zhu and Fuhui Wang state key {2. for Corrosion and Protection, Institute of Metal Research,{3., Shenyang 110015, china [a] state key {2. for Corrosion and Protection Institute of Metal Research chinese academy of {2. Shenyang 110015 china

A single water monomer is known as a hard-to-observe molecule even in the presence of metal surfaces as supporting matrix. This review highlights effort in experimental characterizations and theoretical modeling of transition metals supported water monomers with attention given to its structure and bonding, together with the insights that we have provided into the bonding nature of the water-interactions by the newly employed projected PDOS （partial density of states） difference analysis, which is proved to be an effective tool to be elucidate such bonding nature. The general s-d hybridization and d-shell effect are summarized, and how these effects can be tuned by tailoring local surface configurations is discussed.

关键词： Water monomer Adsorption Surface bonding Transition metals

Energy Transfer among Chlorophylls in Trimeric Light-harvesting Complex Ⅱ of Bryopsis corticulans

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Acta Biochimica et Biophysica Sinica 2006年第5期38卷 310-317页

作者： Su-Juan ZHANG~(1,2.)Shui-Cai WANG~2.Jun-Fang HE~2.Hui CHEN~3. 1 Institute of Photonics and Photo-Technology,Northwest University,Xi'an 710069,{3. 2.state {2. laboratory of Transient Optics and Photonics,Xi 'an Institute of Optics and Precision Mechanics,chinese academy of sciences,Xi'an 710068.{3. 3.Laboratoty of Photosynthesis Basic Research,Institute of Botany,chinese academy of sciences,Beijing 100093.{3. Institute of Photonics and Photo-Technology Northwest UniversityXi'an 710069 China state key {2. of Transient Optics and Photonics Xi'an Institute of Optics and Precision Mechanics Chinese Academy of SciencesXi'an 710068 China laboratory of Photosynthesis Basic Research Institute of Botany Chinese Academy of SciencesBeijing 100093 China

A study on energy transfer among chlorophylls（Chls）in the trimeric unit of the major light-harvesting complex Ⅱ（LHC Ⅱ）from Bryopsis corriculan,was carried out using time-correlated singlephoton *** the chlorophyll Q region of LHC Ⅱ,six molecules characterized as Chlb62.,Chlb646,Chlb652.54,657,Chla664666,Chla674677.680and Chla682.83.ere discriminated according to their absorption spectrumand fluorescence emission ***,excited by pulsed light of 62. nm,fluorescence kinetics spectrain the chlorophyll Q region were *** accordance with the principles of fluorescence kinetics,thesekinetics data were analyzed with a multi-exponential *** constants on energy transfer were *** overwhelming percentage of energy transfer among chlorophylls undergoes a process longer than 97picoseconds（ps）,which shows that,before transferring energy to another Chl,the excited Chl might convertenergy to vibrations of a lower state with different multiplicity（intersystem crossing）.Energy transfer at thelevel of approximately 10 ps was also obtained,which was interpreted as the excited Chls may go throughinternal conversion before transferring energy to another *** with a higher standard deviation,timeconstants at the femtosecond level can not be entirely excluded,which can be attributed to the ultrafastprocess of direct energy *** to the arrangement and direction of the dipole moment of Chls inLHC Ⅱ,the probability of these processes is *** fluorescence lifetimes of Chlb652.54,657,Chla664666,Chla674677.680and Chla682.83.ere determined to be 1.44ns,1.43.ns,63. ps and 713.ps,*** of energy dissipation in the pathway of fluorescence emission were no more than 40% in thetrimeric unit of LHC Ⅱ.These results are important for a better understanding of the relationship between thestructure and function of LHC Ⅱ.

关键词： energy transfer LHC Ⅱ transient spectrum fluorescence kinetics

Discovery of microchromosomes in wheat and their special behavior in meiosis

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chinese Science Bulletin 1997年第24期42卷 2084-2087页

作者： XU Qi, YU Ling, TIAN Zengrong, ZHU Jianfeng, LI Bin and LI Zhensheng laboratory of Plant Genetic Engineering and Breeding of Shaanxi Province, Northwestern Institute of Botany, chinese academy of sciences, Yangling, Shaanxi 712.00,{2. 2. state key laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics, chinese academy of sciences, Beijing 100101,{2. laboratory of Plant Genetic Engineering and Breeding of Shaanxi Province Northwestern Institute of Botany Chinese Academy of Sciences Yangling Shaanxi 712100 China

THERE are 42.chromosomes in common wheat (Triticum aestivum L). The extra microchro-mosomes were discovered in alloplasmic lines of common wheat with cytoplasms of Ae. muti-ca, Secale cereale, Elytrigia elongatum and Agropyron glaucum. The microchromo-somes were discovered in amphiploid of Triticum aestivum-Secale cereale (DDRR) too.

关键词： wheat microchromosomes behavior in meiosis.

Asymmetric Catalytic Hydrogenation Using Rhodium Diphosphinites Derived From D-glucose and D-mannitol

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chinese Chemical Letters 2000年第7期11卷 587-588页

作者： Peng JIANG Shi Jie LU(state key {2. of Oxo Synthesis and Selective Oxidation, {3. Institute of Chemical Physics, chinese academy of sciences, lanzhou 73.000) chinese Acad Sci Lanzhou Inst Chem Phys State Key Lab Oxo Synth & Select Oxidat Lanzhou 730000 Peoples R China

Three diphosphinites were synthesized for preparing rhodium-diphosphinite complexes. The complexes were used for asymmetric catalytic hydrogenation of amino acid precursor alpha-acetamidocinnamic acid and its methyl e... 详细信息

关键词： asymmetric catalysis hydrogenation rhodium diphosphinites alpha-acetamidocinnic acid

The gravitational gradient tensor’s invariants and the related boundary conditions

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Science china Earth sciences 2010年第5期53卷 781-790页

作者： YU JinHai1,2.3.& ZHAO DongMing4 1 College of Earth Science, Graduate University of chinese academy of sciences, Beijing 100049, china 2.Institute of Geodesy and Geophysics, chinese academy of sciences, Wuhan 43.077, china 3.state key laboratory of Astronautic Dynamics, Xi’an 710043. china 4 Zhengzhou Institute of Surveying and Mapping, Zhengzhou 450052. china 1. College of Earth Science Graduate University of Chinese Academy of Sciences Beijing 100049 China2. Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China3. State Key Laboratory of Astronautic Dynamics Xi’an 710043 China4. Zhengzhou Institute of Surveying and Mapping Zhengzhou 450052 China

Here we report new approaches of recovering the Earth gravitational field from GOCE (Gravity field and steady-state Ocean Circulation Explorer) gradiometric data with the help of the gradient tensor’s invariants. Our results only depend on GOCE satellite’s position and gradiometry, in other words, they are completely independent of the satellite attitude. First, starting from the invariants, linearization models are established, which can be referred as the general boundary conditions on the satellite’s orbit. Then, the spherical approximation expressions for the models are derived, and the corresponding solving methods for them are discussed. Furthermore, considering effects of J2.term, the spherical approximation models are improved so that the accuracies of the boundary conditions can be theoretically raised to O ( J 2.2.T), which is approximately equivalent to O(T2.. Finally, some arithmetic examples are constructed from EGM96 model based on the derived theories, and the computational results illustrate that the spherical models have accuracies of 10-7 and the order recovering the gravitational field can reach up to 2.0, and the models with regard to effect of J2.term have accuracies of 10-8 and the order can reach up to 2.0.

关键词： the Earth’s gravitational field gravitational gravidiometry tensor’s invariant

Pollen limitation and variation in floral longevity in gynodioecious Potentilla tanacetifolia

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Journal of Systematics and Evolution 2011年第6期49卷 539-545页

作者： 1,2.ong YAO 1Yi-Bo LUO 1(state key {2. of Systematic and Evolutionary Botany,Institute of Botany,chinese academy of sciences,Beijing 100093.china) 2.Graduate University of the chinese academy of sciences,Beijing 100049,china) (state key {2. of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (Graduate University of the chinese academy of sciences Beijing 100049 China) *Correspondence: Yi-Bo LUO *Correspondence: E-mail: luoyb@*** Tel.: 86-10-62.3.514 Fax: 86-10-62.90843.

Pollination limitation is common in flowering plants and is thought to be a factor driving the evolution of floral *** plasticity of floral longevity to pollination may be an adaptation of plants to pollen ***,this adaptation is less critical in short-lived *** evaluate pollen limitation and the plasticity of floral longevity to pollination in Potentilla tanacetifolia,a gynodioecious herb with short-lived flowers,we analyzed its breeding system,tested sex-differential pollen limitation,and compared variations in floral display size in natural populations in Duolun County,Inner Mongolia,*** pollination experiments and pollinator exclusion treatments revealed that *** is self-compatible and non-autonomously apomictic and shows sex-differential pollen *** plasticity of floral longevity to pollination was observed;the floral duration of female plants was prolonged by approximately 3.4 hours with pollination exclusion ***,the percentage of flowers displayed on female plants during pollination exclusion treatment was significantly higher than that during natural *** natural pollination conditions,the percentage of flowers displayed on female plants was significantly higher than on hermaphrodite ***,approximately 50%of the pollen grains spread out of the anthers of hermaphrodite flowers within 2.h of anthesis;the number of pollen grains adhering to the stigmas of hermaphrodite flowers was significantly higher than that adhering to female flowers when flowers shed their *** results indicate that variation in floral longevity may be an adaptive strategy to pollination conditions for gynodioecious ***.

关键词： floral longevity gynodioecy plasticity pollen limitation Potentilla tanacetifolia.

Numerical simulation of Richtmyer-Meshkov instability

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Science china Mathematics 2004年第z1期47卷 234-244页

作者： FU Dexun, MA Yanwen, ZHANG Linbo & TIAN Baolinstate key {2. of Nonlinear Mechanics, Institute of Mechanics,{3., Beijing 100080, china state key {2. of Scientific and Engineering Computing, Institute of Computational Mathematics,{3., Beijing 100080, china 1. state key {2. of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences 100080 Beijing China2. State Key Laboratory of Scientific and Engineering Computing Institute of Computational Mathematics Chinese Academy of Sciences 100080 Beijing China

The compressible Navier-Stokes equations discretized with a fourth order accurate compact finite difference scheme with group velocity control are used to simulate the Richtmyer-Meshkov (R-M) instability problem produced by cylindrical shock-cylindrical material interface with shock Mach number Ms=1.2.and density ratio 1:2. (interior density/outer density). Effect of shock refraction, reflection, interaction of the reflected shock with the material interface, and effect of initial perturbation modes on R-M instability are investigated numerically. It is noted that the shock refraction is a main physical mechanism of the initial phase changing of the material surface. The multiple interactions of the reflected shock from the origin with the interface and the R-M instability near the material interface are the reason for formation of the spike-bubble structures. Different viscosities lead to different spike-bubble structure characteristics. The vortex pairing phenomenon is found in the initial double mode simulation. The mode interaction is the main factor of small structures production near the interface.

关键词： R-M instability, direct numerical simulation, shock-interface interaction.

Electrochemical Corrosion Behavior of Nanocrystalline Materials-a Review

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Journal of Materials Science & Technology 2010年第1期26卷 1-14页

作者： Li Liu, Ying Li and Fuhui Wang state key {2. for Corrosion and Protection, Institute of Metal Research,{3., Shenyang 110016, china [a] state key {2. for Corrosion and Protection Institute of Metal Research chinese academy of {2. Shenyang 110016 china

Nanocrystallization significantly influences the electrochemical corrosion behaviors of metals/alloys in liquid system. In active dissolution, nanocrystallization accelerates the corrosion reactions. If the corrosion products are dissoluble, the corrosion rate is increased by nanocrystallization; if the corrosion products are insoluble, the corrosion rate is decreased on the contrary because the corrosion products act as a block layer to delay the dissolution. In passivation, nanocrystallization changes the composition of the passive film, and results into different morphology and growth process of the passive film, both of which improves the formation of compact film and influences the semiconductor property. It influences the passivation depending on fast element diffusion and special adsorbed ability. The small grain size improves the element diffusion, which leads to the different composition of passive film （passive elements enrichment such as Cr, Ti）. The small grain size also changes the surface condition, which influences the ions adsorption. All increase the corrosion resistance of materials. In local corrosion, nanocrystallization increases the unstable points on the surface of the materials, which increases the possibility of local corrosion. However, the excellent ability of element diffusion helps heal the local corrosion points, which inhibits the growth of the local corrosion.

关键词： Nanocrystalline materials Electrochemical corrosion Review

Embryonic and adult neural stem cell research in china

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Science china(Life sciences) 2010年第3期53卷 338-341页

作者： JIAO JianWei Institute of Neuroscience,state key {2. of Neuroscience,{3. academy of sciences,Shanghai 2.003.,china 1. Institute of Neuroscience State Key Laboratory of Neuroscience Chinese Academy of Sciences Shanghai 200031 China

Neural stem cells(NSCs) are one specific type of multipotential stem cells that have the ability to proliferate for a long time and to differentiate into neural cells,including neurons,astrocytes and *** NSCs exist in both the embryonic and adult central nervous system(CNS) of all mammalian *** has been made in the understanding of the developmental regulation of NSCs and their function in *** review discusses recent progress in this area,with emphasis on work done by investigators in china.

关键词： neural stem cells neurogenesis stem cell niche reprogramming hippocampus