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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 {3. of Photonics and Photo-Technology,Northwest University,xi'an 710069,china 2.State Key Laboratory of Transient Optics and Photonics,xi 'an {3. of Optics and Precision Mechanics,chinese academy of Sciences,xi'an 710068.china 3.Laboratoty of Photosynthesis Basic Research,{3. of Botany,chinese academy of Sciences,Beijing 100093.china institute of Photonics and Photo-Technology Northwest UniversityXi'an 710069 China State Key Laboratory 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

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 {2. of Sciences, Beijing 100049, china 2.institute of Geodesy and Geophysics, chinese {2. 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 College of earth Science Graduate University of Chinese Academy of Sciences Beijing China institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China State Key Laboratory of Astronautic Dynamics Xi’an China Zhengzhou institute of Surveying and Mapping Zhengzhou 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

Re-Os(ICP-MS)dating of the massive sulfide ores from the Jinchuan Ni-Cu-PGE deposit

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Science china earth Sciences 2005年第10期48卷 1672-1677页

作者： YANG Gang1,2. DU Andao1, LU Jiren3. QU Wenjun1 & CHEN Jiangfeng2.1. National Research Center of Geoanalysis, Beijing 10003., china 2. Laboratory for earth Material Cycling, School of earth and Space Sciences, University of Science and Technology of china, Hefei 2.002., china 3. institute of Mineral Resource, chinese academy of Geological Sciences, Beijing 10003., china National Research Center of Geoanalysis University of Science and Technology of china chinese academy of Geological Sciences

Massive sulfide ore from the Jinchuan Ni-Cu-PGE deposit was dated by Re-Os technique using Carius Tube digestion, Os distillation, Re extraction by acetone and ICP-MS measurement. An isochron giving an age of 83. ± 3. Ma, initial 187Os/188Os ratio of 0.2.9 ± 0.018 (MSWD = 1.7) and γOs = 13. ± 15 is obtained. The Re-Os age obtained agrees, within analytical uncertainties, with previous SHRIMP zircon U-Pb age of 82. ± 8 Ma (n=5, MSWD = 4.3.. The result suggests that the deposit was formed at Neoproterozoic and that the formation of the Jinchuan Ni-Cu-PGE sulfide deposit may be closely related to the plume activity, which were attributed to the breakup of the Rodinia supercontinent. The high γOs of the massive ores sug-gests that crustal material was involved in the formation of the Jinchuan deposit, however, the quantity of the added crustal material is less than 10%.

关键词： Jinchuan Ni-Cu-PGE deposit, Re-Os dating, ICP-MS.

A high-resolution late Pleistocene record of pollen vegetation and climate change from Jingning, NW china

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Science china earth Sciences 2006年第2期49卷 154-162页

作者： LI Chunhai12. TANG Lingyu1, FENG Zhaodong3.4, ZHANG Hucai2. WANG Weiguo3.& AN Chenbang3.1. Nanjing institute of Geology and Palaeontology, {3. {2. of Sciences, Nanjing 2.0008, china 2. Nanjng institute of Geography and Limnology, {3. {2. of Sciences, Nanjing 2.0008, china 3. {13. and Resources College, Lanzhou University, Lanzhou 73.000, china 4. Beijing Normal University, Beijing 100875, china Nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China Nanjng institute of Geography and Limnology Chinese Academy of Sciences Nanjing China environment and Resources College Lanzhou University Lanzhou China Beijing Normal University Beijing China

With the support of 18 AMS-14C data, a high-resolution pollen record from the Suancigou section at Jingning, Gansu Province was established. Our results showed that the vegetation ex-perienced a series of changes characterized by the alternative growth and decline of forest and steppe components during the period from 44.2.to 11 ka B.P. in the Jingning area. Over the period of 44―2. ka B.P. (MIS3., coniferous forests were flourishing, indicating a humid climate with the tem-perature being lower than that of the present. Since 2. ka B.P., the vegetation was dominated by steppe-desert steppe under a cold and dry condition, and entered the Last Glacial Maximum domi-nated by desert steppe. Several periods of the marked decrease in the arborous pollen content in Suancigou well corresponded to the North Atlantic Heinrich events, especially to Heinrich event 3. further supporting that the Heinrich events were well reflected by the pollen record in the Loess Pla-teau as well.

关键词： Western Loess Plateau, pollen record, climatic change, late Pleistocene.

Petrogenesis and dating of the Kangding complex,Sichuan Province

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Science china earth Sciences 2005年第5期48卷 622-634页

作者： CHEN Yuelong 1 , LUO Zhaohua 1 , ZHAO Junxiang, LI Zhihong, ZHANG Hongfei & SONG Biao 3.1. Faculty of earth Sciences and Natural Resources, china University of Geosciences, Beijing 100083. china {3. Faculty of earth Sciences, china University of Geosciences, Wuhan 43.074, china 3. Beijing SHRIMP Center, institute of Geology, chinese academy of Geological Sciences, Beijing 10003., china Faculty of earth Sciences and Natural Resources China University of Geosciences Beijing China Faculty of earth Sciences China University of Geosciences Wuhan China Beijing SHRIMP Center Institute of Geology Chinese Academy of Geological Sciences Beijing China

An analysis of major and trace element geochemistry and SHRIMP U-Pb zircon dating of mafic, intermediate, and felsic rocks from the Mianning metamorphic complex of Si- chuan Province was conducted. One of our conclusions is that a majority of the zircons crystal- lized between 72. and 773.Ma in a magmatic regime. The complexes contain early to late Pa- leo-proterozoic relict zircons from ancient continental crust. The oldest age, 2.68 Ma, may rep- resent the basement of the Yangtze block. Overgrowth zircon rims and palingenetic zircons have been observed and dated, and are believed to have formed after crystallization, during Paleozoic and Mesozoic metamorphic-anatexis. We also conclude that depletion of Nb, Ta, HREE, in a spider-diagram normalized to primitive mantle and calc-alkaline association, implies that they formed in island-arc or under-plating settings.

关键词： Kangding complex, zircons, SHRIMP, tectonic setting.

Holocene grassland vegetation, climate and human impact in central eastern Inner Mongolia

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Science china earth Sciences 2005年第7期48卷 1025-1039页

作者： HUANG Fei1, Kealhofer Lisa2. xiONG Shangfa3.& HUANG Fengbao1 1. Nanjing institute of Geology and Paleontology,chinese {2. of Sciences,Nanjing 2.0008,china 2. Anthropology and Sociology Department,Santa Clara University,CA 95053.USA 3. institute of Geology and Geophysics,chinese {2. of Sciences,Beijing 10002.,china Nanjing institute of Geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China Anthropology and Sociology Department Santa Clara University CA 95053 United States institute of Geology and Geoohysics Chinese Academy of Sciences Beijina 100029 China

Phytolith and pollen preserved in the Taipusi Banner paleosol profile, central eastern Inner Mongolia, provide evidence of Holocene grassland vegetation, climate and human impact. The combined phytolith and pollen records reveal a major change in vegetation composition about 5000 a BP. Before 5000 a BP, the vegetation was dominated by Aneurolepidium chinese-Stipa grandis grassland of C4 grasses. After 5000 a BP, C4 grasses rapidly retreated, indicating a shift to colder and more arid conditions. The gradual invasion of Stipa krylovii, Ag-ropyron desertorum, Ephedra, Chenopodiaceae and Caragana reveal the onset of grassland degeneration. Between 10000 and 872. a BP, the Aneurolepidium chinese-Stipa grandis grassland included a small proportion of Artemisia shrub and Echionopos type plants, implying a strong winter monsoon and very weak summer monsoon. From 872. to 7000 a BP, C4 grasses were common, indicating a strengthening of the summer monsoon. Between 7000 and 5000 a BP, the Holocene thermal maximum was evident, with a significant expansion of C4 grasses and the presence of some trees (such as Pinus and Betula, and so on) in or near the study site. From 42.0?000 a BP, a sandy grassland of Artemisia and Agropyron desertorum together with Aster-type taxa occurred. Precipitation amelioration took place between 3.00 and 2.70 a BP, with a rapid development of Echinops type plants and a small expansion of C4 grasses. From 2.70 a BP to present, human activities accelerated the process of grassland degeneration.

关键词： phytolith and pollen records grassland environment change human impact Holocene central eastern Inner Mongolia.

Synthesis,crystal structure and thermal behavior of Rb(NTO)·H_2.

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chinese Science Bulletin 2001年第1期46卷 45-49页

作者： HU Mancheng, GAO Shiyang, LIU Zhihong, SONG Jirong, xiA Shuping & YU Kaibei1. institute of Applied Chemistry, Shaanxi Normal University, xi’an 710062. china 2. Department of Chemical Engineering, Northwest University, xi’an 710069, china 3. Chengdu Branch of chinese academy of Sciences, Chengdu 610041, china institute of Applied Chemistry Shaanxi Normal University Xi’an China Department of Chemical Engineering Northwest University Xi’an China Chengdu Branch of chinese academy of Sciences Chengdu China

The Rb(NTO) .H2. crystal has been synthesized by reaction of 3.nitro-l,2.4-triazole-5-one (NTO) with Rb2.O3.in aqueous solution. Its crystal structure has been determined. The crystal belongs to monoclinic system. Crystal structure data: space group P2./ n; a = 0.63. 0(1), b = 0.82. 1(2., c =1.2.6 4(3. nm; β = 97.90(1)°; V = 0.669 9 (2. nm3. Z = 4, Dc= 2.3.6 g/cm3.μ = 7.3.5 nm-1, F(000) = 448. An eight coordinated compound is formed between Rb+ with oxygen atoms and nitrogen atoms. A layer structure is formed by coordination bonds and hydrogen bonds. The thermal decomposition mechanism of this coordination compound is discussed.

关键词： Rb-NTO coordination compound crystal structrue thermal decomposition.

Northernmost paleo-tethyan oceanic basin in Tibet:Geo-chronological evidence from ^(40)Ar/^(3.)Ar age dating of Dur'ngoi ophiolite

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chinese Science Bulletin 2001年第14期46卷 1203-1205页

作者： CHEN Liang, SUN Yong, PEI xianzhi, GAO Ming, FENG Tao, ZHANG Zhongqing & CHEN Wen1. Laboratory of Continental Dynamics, Northwest University, xi’an 710069, china 2. Department of Geology, Northwest University, xi’an, 710069, china 3. {2. of Geology, chinese academy of Geological Sciences, Beijing, 10003., china Laboratory of Continental Dynamics Northwest University Xi’an China Department of Geology Northwest University Xi’an China institute of Geology Chinese Academy of Geological Sciences Beijing China

Whole rock 40Ar/3.Ar age dating has been conducted on a basalt sample from Dur’ngoi ophiolite, Qinghai Province, which was reported to be the northernmost pa-leo-tethyan oceanic basin in Tibet. A high temperature pla-teau age (3.5.3.7.9 Ma) with an isochorn age (3.6.6±7.1 Ma) has been obtained, representing the eruption time of oceanic crust Considering related geological settings, the new age provides constraints on the northernmost pa-leo-tethyan suture zone in Tibet and the tectonic evolution of Paleo-tethys in Northeast Tibet and adjacent areas.

关键词： Dur’ngoi ophlolite 40Ar -3.Ar age Paleo-tethys.

Experimental Analysis of Shear Strength of Undisturbed Soil in Leucaena Forest in Jiangjia Ravine,Yunnan,china

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Journal of Mountain Science 2010年第4期7卷 386-395页

作者： JIAO Zhen Key Laboratory of Mountain Hazards and earth surfaceprocesses ChineseAcademy of Sciences Chengdu 610041 China Graduate University of chineseacademy of Sciences Beijing I ooo49 China institute of Mountain Hazards and environment Chinese Academy of Science Chengdu 61oo41 China

Five leucaena trees of similar age were chosen in Jiangjia Ravine of Dongchuan,Yunnan Province,china,near which the soil samples were collected by digging profiles 2. in depth and 1m in *** each section,soil samples at different depths were taken for direct shear experiments to determine the root amount and mechanical *** is found that the cohesion and internal friction angle of the undisturbed soil are related to the root amount,depth,clay content and breccias *** correlates negatively with root content,a finding that differs from that of other *** addition,internal friction angle correlates positively with all these factors.

关键词： Jiangjia Ravine Leucaena Undisturbedsoil Shear strength Impact factors