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Forcing mechanism of the Pleistocene east Asian monsoon variations in a phase perspective

Science china Earth Sciences 2005年第10期48卷 1708-1717页

作者： TIAN Jun1,2. WANG Pinxian1, CHENG Xinrong1, WANG Rujian1 & SUN Xiangjun1,3.1. State Key Laboratory of Marine Geology, Tongji University, Shanghai 2.0092. {3. 2. institute of Geology and Geophysics, {2. Academy of Sciences, Beijing 10002., {3. 3. institute of Botany, {2. Academy of Sciences, Beijing 100093. {3. Tongji University chinese Academy of Sciences

The deep sea records from the ODP Sites 1143.and 1144 in the northern and southern South china Sea (SCS), including foraminiferal δ 18O and δ 13., Opal% and pollen percentage, reveal that the variations of the east Asian monsoon have been closely correlated with the variations of the Earth’s orbital parameters (eccentricity, obliquity and precession) and the global ice volume on orbital scale. All the monsoonal proxies show strong 100 ka, 41 ka and 2. ka cycles. Although G. ruber δ 13. of Site 1143.is coherent with the ETP (ETP= normalized (eccentricity + obliquity-precession) at eccentricity, obliquity and precession bands, most of the coherent relationship focuses on the precession band, and the other monsoonal proxies are coherent with the ETP only at the precession band, which indicate that precession dominates the Pleistocene tropical climate changes. The phase relationship of the monsoonal proxies with the foraminiferal δ 18O implies that the global ice volume changes have played a significant role in modulating the east Asian monsoon climate, at least dominating the winter monsoon. This forcing mechanism of the east Asian monsoon is apparently different from that of the Indian ocean mon-soon. The variations of the east Asian monsoon at the precession band, at least that of the winter monsoon, have been controlled not only by the sensible heating but also by the latent heating of the surface water in the South china Sea.

关键词： South china Sea, ODP, east Asian monsoon, orbital forcing, global ice volume.

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Synthesize TiO_2.microspheres self-assembled from nanorods via hydrothermal treatment

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Science china chemistry 2007年第2期50卷 175-178页

作者： ZHANG YiBing1,2.FENG XinJian3.& JIANG Lei2.3.1 Shangrao Teachers’ College,Shangrao 3.4001,china 2.National Center for Nanoscience and Nanotechnology,Beijing 100080,china 3.institute of chemistry,chinese Academy of Sciences,Beijing 100080,china Shangrao Teachers’ College Shangrao China National Center for Nanoscience and Nanotechnology Beijing China institute of chemistry Chinese Academy of Sciences Beijing China

The TiO2.microspheres were deposited on the glass substrates under certain conditions via hydro-thermal reaction using 0.15 mol·L?1 TiCl3.saturated NaCl aqueous solution adding urea as an additive. The TiO2.is characterized rutile by results of SEM,TEM and XRD techniques,the TiO2.microspheres are large scale assembled from TiO2.nanorods. The affections on the products by the factors of the con-tents of urea being an additive(the key techniques) ,the reaction temperature,the reaction time and the concentration of TiCl3.were studied. The optimum condition was found,and the mechanism of reac-tions was discussed also.

关键词： TiO2 self-assembly nanorods microsphere hydrothermal reaction

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Relationships between tree-ring width index and NDVI of grassland in Delingha

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chinese Science Bulletin 2006年第9期51卷 1106-1114页

作者： HE Jicheng1,3.& SHAO Xuemei1,2.. institute of Geographical Sciences and Natural Resources Research, chinese Academy of Sciences, Beijing 100101, {2. 2. institute of Tibetan Plateau Research, chinese Academy of Sciences, Beijing 100085, {2. 3. Graduate School of chinese Academy of Sciences, Beijing 10003., {2. institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Graduate School of chinese Academy of Sciences Beijing China institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China

Using five well-replicated Qilian juniper (Sabina przewalskii Kom.) tree-ring width index se- ries, monthly normalized difference vegetation index (NDVI) of grassland, and climatic data from 1982.to 2.01, the relationships between tree-ring width index, NDVI of grassland, and climatic data were analyzed firstly. Then, the relationship between tree-ring width index and NDVI of grassland was explored. The re- sults showed that: (1) Temperature and precipitation in June influenced tree-ring width index and NDVI of grassland deeply in Delingha. (2. There were sig- nificant relationships between five tree-ring width index series (DLH1-DLH5) and monthly NDVI of grassland from June to September, with the most significant relationship being between tree-ring width index series and NDVI of grassland in August. (3. The PC1 (the first principal component derived from DLH1-DLH5 series) exhibited good agreement with monthly NDVI of grassland in the grass growth sea- son (from June to September) and the averaged NDVI in the growth season, which was attributed to their common responses to water-supply limit in Delingha. This study may allow an increase in studying the past dynamics of grassland in Delingha in that the variation of grassland NDVI during the last millennium has been reconstructed from PC1.

关键词：圆柏祁连山 NDVI 草原年轮宽度指数

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Ultrafast excitation relaxation in light-harvesting complex LH2.from *** 601

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Science china chemistry 2004年第3期47卷 192-199页

作者： GUO Lijun1,2. LIU Yuan3. LIU Weimin2. GUO Junhua1, XU Chunhe3.& QIAN Shixiong2.1. School of Physics and Information Optoelectronics, Henan University, Kaifeng 475001, {3. 2. Physics Department, Fudan University, Shanghai 2.043., {3. 3. Shanghai {2. of Plant Physiology, chinese Academy of Sciences, Shanghai 2.003.0} {3. School of Physics and Information Optoelectronics Henan University Kaifeng 475001 China

The energy relaxation and kinetic evolution of transient spectra of bacteriochloro- phylls (BChls) in light-harvesting complex LH2.from Rb. sphaeroides 601 were investigated using femtosecond pump-probe technique. Upon 783.nm excitation, the energy at B800 BChls ex-periences an intramolecular redistribution with 0.3. ps time constant before transferring to B850 BChls. With tuning the excitation wavelength, the dynamical evolution of excited BChls was clearly observed, which indicates an obvious competition between the ground state bleaching and excited state absorption (ESA) of BChls involved and an isosbestic point near 818 nm, and also demonstrates that from the lower electronic excited state of B800 BChls to the higher exci-tonic state of B850 BChls is an efficient routine for energy transfer. The excitation energy in higher excitonic states of B850 BChls relaxes rapidly to the next lowest excitonic state by inter-conversion, delocalization to adjacent molecular, populating the lowest excitonic state and the change of molecular conformation.

关键词： photosynthesis, light-harvesting complex, energy transfer, ultrafast, dynamics, purple bacteria.

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Relationship between magnetic fabric parameters and dynamic characteristics of deposits in different environments

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chinese Science Bulletin 1998年第22期43卷 1917-1921页

作者： CHEN Qingqiang 1,3., LI Congxian\+1 and CONG Youzi\+2.1. Marine Geology Laboratory, Tongji University, Shanghai 2.0092. {3. 2. First institute of Oceanography, State Oceanic Administration of {3., Qingdao 2.6003. {3. 3. Guangzhou institute of Marine Geology Laboratory Tongji University Shanghai China Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou China First institute of Oceanography State Oceanic Administration of China Qingdao China

Comparison of magnetic fabric parameters of deposits in different modern sedimentary environments indicates that values of \%P, F\% and \%L\% of eolian deposits are lower obviously than those of hydrogenic ones respectively. On relationship diagrams of magnetic fabric parameters, data points of eolian samples concentrated in limited area near origin of coordinates indicate that dynamic intensity is lower with less variation; while those of hydrogenic ones depart from origin of coordinates suggest higher intensity of sedimentary dynamics. Analyses of dynamic characteristics of different sedimentary environments indicate that values of magnetic fabric parameters of deposits are determined by dynamic types and characteristics of depositional processes. Magnetic fabric analyses of deposits are effective in determination of sedimentary environments.

关键词： magnetic fabric parameters sedimentary environment transporting medium.

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Discovery of seep carbonate nodules as new evidence for gas venting on the northern continental slope of South china Sea

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chinese Science Bulletin 2006年第10期51卷 1228-1237页

作者： CHEN Zhong1,2.3. YAN Wen1,2.3. CHEN Muhong1,3. WANG Shuhong1,2.3. LU Jun1,3. ZHANG Fan1,3. XIANG Rong1,3. XIAO Shangbin1,3. YAN Pin1,2.3.& GU Senchang1,2.3.1. South china Sea institute of Oceanology, {2. Academy of Sci-ences, Guangzhou 5103.1, china 2. Guangzhou Center for Gas Hydrate Research, {2. Academy of Sciences, Guangzhou 5103.1, china 3. Key Laboratory of Marginal Sea Geology, South china Sea institute of Oceanology and Guangzhou institute of Geochemistry, {2. Academy of Sciences, Guangzhou 5103.1, china South china Sea institute of Oceanology Chinese Academy of Science Guangzhou China Guangzhou Center for Gas Hydrate Research Chinese Academy of Sciences Guanzhou China Key Laboratory of Marginal Sea Geology South China Sea Institute of Oceanology and Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China

Seep carbonate nodules were firstlycollected from the southwestern Dongsha area onnorthern continental slope of South china Sea formineralogical and geochemical studies. The resultsof X-ray diffraction show that carbonate nodules arecomposed of Fe-rich domolite,siderite and a few cal-cite and aragonite, as well as a small quantity ofnon-carbonate minerals such as goethite, quartz andclay minerals. Fe-rich dolomite and siderite charac-terized by euhedral microcrystalline structure weredirectly precipitated at cold seeps. The δ 13. valuesfor Fe-rich dolomite and siderite in the bulk nodulesvary from ?18.2.‰ to ?3..07‰, and the δ 18O valuesrange from 0.42.to 2.76‰. Their moderate depleted13. reflects that carbon origin is possibly thermoge- netic gas or mixed gas, which is evidence of gasventings in the seafloor. Moreover, massive wormtube fossils related to cold seeps were found on thesurfaces of carbonate nodules, and the conduitsand/or channels in semi-solidified nodules whichwere not filled by carbonate or sediment were alsoobserved. A preliminary conclusion is that activemicro gas venting with a conduit/channel diameterrange from 2.0 μm to 600 μm possibly exists inmodern seafloor of the carbonate nodule area.

关键词：渗出碳酸盐节碳氧同位素甲烷渗漏天然气水化物

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Inertial theory of the mean Hadley circulation under the condition of nonstatic equilibrium

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Science china Earth Sciences 2006年第5期49卷 546-553页

作者： CHAO Jiping1 & LIU Fei2.3.1. National Marine Environmental Forecasting Center, Beijing 100081, china 2. Key Laboratory Regional Climate-Environment for Temperate East Asia, {3. of Atmospheric Physics, {2. Academy of Sciences, Beijing 10002., china 3. Graduate University of {2. Academy of Sciences, Beijing 100049, china National Marine Environmental Forecasting Center Key Laboratory Regional Climate-Environment for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Graduate University of chinese Academy of Sciences

Tropical atmosphere is divided into two layers, the layer near the ground is the planet boundary layer, where the motion is linear, if the radiation equilibrium temperature is given at the top of the boundary layer, the vertical motion there can be obtained. It is the non-viscous ideal atmos- pheric layer above the boundary one, where the motion is nonlinear. After getting the conservation laws of angular momentum, potential temperature and potential vortex, the inertial theory of the Hadley circulation driven by the vertical motion of the boundary layer is established, followed by sev- eral examples of its application.

关键词： Hadley circulation, inertial theory, conservation laws of angular momentum, potential temperature and potential vortex.

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The effects of K^+ growth conditions on the accumulation of cesium by the bacterium Thermus sp. TibetanG6

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Science china(Life Sciences) 2006年第2期49卷 123-129页

作者： WANG Hailei1,2.3. KONG Fanjing1,2.3.& ZHENG Mianping1,2.3.1. R&D Center for Saline Lake and Epithermal Deposits, {3. Academy of Geological Sciences, Beijing 10003., china 2. Key Open Laboratory of Saline Lake Resources and Environment, {3. Academy of Geological Sciences, Beijing 10003., china 3. institute of Mineral Resources, {3. Academy of Geological Sciences, Beijing 10003., china R&D Center for Saline Lake and Epithermal Deposits Chinese Academy of Geological Sciences Beijing China Key Open Laboratory of Saline Lake Resources and Environment Chinese Academy of Geological Sciences Beijing China institute of Mineral Resources Chinese Academy of Geological Sciences Beijing China

The accumulation of cesium by the bacterium Thermus sp. TibetanG6 was examined under different K+ growth conditions. The effects of external pH and Na+ on the accumulation of ce-sium were also studied, and the mechanism involved was discussed. K+ regimes played an important role in the accumulation of cesium by the strain TibetanG6. The quantity of cesium accumulated (2. h) was much higher in K+-deficient regime than that in K+-sufficient regime. The pH and Na+ had different effects on the accumulation of cesium in the two K+ regimes. IR spectra analyses indicated that the biosorption is a process of homeostasis with cesium initially accumulated on the cell wall.

关键词： Thermus sp. TibetanG6, cesium, bioaccumulation, K+-growth condition, pH, sodium, IR spectroscopy.

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Structures and stability of isomers of[C,N,N,P]system

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Science china chemistry 2005年第5期48卷 415-423页

作者： KAN Wei1,2. ZHONG Hua1, YU Haitao1, FU Honggang1,3.& SUN Jiazhong1,3.1. School of chemistry and Materials Science, Heilongjiang University, Harbin 150080, china 2. School of chemistry and Chemical Engineering, Qiqihar University, Qiqihar 161006, china 3. State Key Laboratory of Theoretical and Computational chemistry, institute of Theoretical chemistry, Jilin University, Changchun 13.02., china School of chemistry and Materials Science Heilongjiang University Harbin China School of chemistry and Chemical Engineering Qiqihar University Qiqihar China Jilin University Changchun China

Nine isomers, twenty transition states, and some relative dissociation fragments of [C,N,N,P] system were located at the B3.YP/6-3.1G(d) and QCISD(t)/6-3.1+G(2.f) (single-point) levels of theory, and the isomerization, structures, and stability of these obtained isomers were suggested. The results indicate that four nonlinear chainlike isomers NCNP, NCPN, CNPN, and CNNP with 2.′ electronic state are kinetically stable. Other isomers are kinetically unstable to-wards isomerization or dissociation because of the corresponding smaller reaction barriers. Furthermore, calculated vibrational frequencies, rotational constants, dipole moments, the first adiabatic ionization energies, and adiabatic electron affinities of the four isomers may provide some theoretical information that is helpful for identifying their existence in future laboratory and interstellar investigations. The results are also compared with [Si,N,N,P] system.

关键词： potential energy surface, [C,N,N,P] system, isomerization, kinetic stability.

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Enzymatic cyclization of linear peptide to plant cyclopeptide heterophyllin B

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Science china chemistry 2006年第1期49卷 63-66页

作者： JIA Aiqun1, LI Xiang2. TAN Ninghua1, LIU Xiaozhu3. SHEN Yuemao1 & ZHOU Jun1 1. State Key Laboratory of Phytochemistry and Plant Resources in West china, Kunming {2. of Botany, Graduate Univer-sity of chinese Academy of Sciences, chinese Academy of Sciences, Kunming 6502.4, china 2. chinese Peptide Co., Ltd, Hangzhou 3.0018, china 3. Southwest Forestry College, Kunming 6502.4, china State Key Laboratory of Phytochemistry and Plant Resources in West china Kunming Institute of Botany Graduate University of Chinese Academy of Sciences Chinese Academy of Sciences Kunming China chinese Peptide Co. Ltd Hangzhou China Southwest Forestry College Kunming China

The crude enzyme (PH-1) isolated from Pseudostellaria heterophylla by ourgroup has catalyzed enzymatic cyclization of linear peptideNH_2.Gly^1-Gly^2.Leu-Pro-Pro-Pro-lle-Phe-COOH (4) into cyclopeptide heterophyllin B (HB) from plantfor the first time. To ensure this reaction, some analytical methods including TLC, HPLC, MS, NMR,and ^(13.C labeling were used to prove that the reaction of substrate 4 sharing residue ofNH-Phe-Gly-CO was successful.

关键词： Pseudostellaria heterophylla, cyclopeptides, HB, enzymatic cyclization, isotope labeled.

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