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Implications of pheuotypic plasticity on iron distribution profiles of plant modules growing in heterogeneous wetland habitat

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Implications of pheuotypic plasticity on iron distribution p...

第三世界生态高峰会

作者： Zou Y.C.~(*1,2) Lu X.G.~1 Jiang M.~1 ~1Northeast Institute of Geography and Agricultural Ecology.CAS,Changchun 130012,china,~2graduate school of chinese academy of sciences.Beijing 100049.china

Carex pseudocuraica,one of the most prevailing rhizomatous perennial herbaceous plants in the sedge family,distribute as the constructive or main companion species in Sanjiang Plain Wetland,northeastern china A clonal unit was defined here as a group of ramets sharing the same tillering *** units were colleted from 4 different patches,namely perennial flooded river water(PW),perennial flooded river sediment(PSed),seasonal flooded river sediment(SSed)o and perennial flooded soil(PS),in the late autumn when they keep alive but nearly stop *** 13 morphology traits,total Fe of 9 plant modules, total Fe and available Fe of substrates were carefully measured as well as the nutritional and chemical contents(available N,available P, available K,TOC,pH)of *** biomass allocation index were calculated based on the data above to indicate the growth strategies used in different *** Analysis was applied to determine 4 factors representing the total 13 morphological traits(the cumulative variance up to 73.53%),and the mean total scores showed thai the highest score was in PW(0.55).next were SSed(0.06)and PSed(-0.38),and the lowest was PS(-0.46).The score order indicated thai the best performance appeared in PW,and that of PS was relatively *** to the correlation analysis between nutrient contents and performaece scores(PW exclusive),it was interesting to find that performance scores were negative correlated to AN,AP,TOC,and pH while positive to AK,TFe,and AFe(R=0.676,0.856,0.985;p=0.527, 0.346,0.111,respectively).The K content oF substrates,therefore, might be the lilniting factor influencing the sedge's performance,and the phenotypic plasticity of the plant was closely correlated with Fe *** biomass allocation index suggested tbat more biomass were assigned to stems and roots to expand colonization when K was adequately *** profile of iron concentration of plant modules,whichever the patch was concerned,

关键词： wetland clonal plant morphological adaptability substrate quality

Analysis of Transcriptional Profiling in Cadmium-Treated Rice （Oryza sativa L.） Seedlings using Suppressive Subtractive Hybridization

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Analysis of Transcriptional Profiling in Cadmium-Treated Ric...

中国植物生理学会第十次会员代表大会暨全国学术年会

作者： Mei Zhang1*, Xuncheng Liu1, Lianyu Yuan1, 2, Keqiang Wu1, Jun Duan1, Xiaolan Wang3, Lixiang Yang3 1South china Botanical Garden, chinese academy of sciences, Guangzhou 510650, china 2graduate school of the chinese academy of sciences, Beijing 100039, china 3Life Science school, Guangzhou University, Guangzhou 510006, china

＜正＞Cadmium, which can be toxic at relatively low concentrations, accumulates in plant tissues including seeds, thus posing a risk to human health through ingestion of grain. To investigate the molecular mechanisms ... 详细信息

关键词： Cadmium Phytotoxicity Suppressive Subtractive Hybridization (SSH) cDNA Microarray Rice

Influence of Mn-O-Mn bond angle on the magnetic and electronic properties in YBaMn2O5

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Influence of Mn-O-Mn bond angle on the magnetic and electron...

中国化学会第二十五届学术年会

作者： H. P. Xiang,1,2 X. J. Liu,1 Z. J. Wu,1,* J. Meng1 1Key Laboratory of Rare Earth Chemistry and Physics, Changchun Institute of Applied Chemistry, chinese academy of sciences, Changchun 130022, P.R.china 2graduate school of the chinese academy of sciences, Beijing, 100049, P.R. china

Infrared Galaxies in the Nearby Universe

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chinese Journal of Astronomy and Astrophysics 2008年第6期8卷 643-652页

作者： Jian-Ling Wang 1 National Astronomical Observatories,chinese academy of sciences,Beijing 100012,china 2 graduate school of chinese academy of sciences,Beijing 100049,china National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China graduate school of chinese academy of sciences Beijing 100049 China

We used the Sloan Digital Sky Survey （SDSS） Data Release 5 （DR5） to study the morphological properties of 1137 nearby infrared （IR） galaxies, most of which are brighter than 15.9 mag in r-band. This sample was drawn from a cross-correlation of the Infra-Red Astronomical Satellite （IRAS） point source catalog redshift survey with DR5 at z ≤ 0.08. Based on this IR galaxy sample, we constructed five volume-limited sub-samples with IR luminosity ranging from 10^9.5 L⊙ to 10^12L⊙. By deriving the IR luminosity functions （LF） for different morphological types, we found that normal spiral galaxies are the dominant population below LIR ~ 8 ~ 10^10 L⊙; while the fraction of barred spiral galaxies increases with increasing IR luminosity and becomes dominant in spiral galaxies beyond LIR ≈ 5 × 10^10L⊙. As the IR luminosity decreases, the IR galaxies become more compact and have lower stellar masses. The analysis also shows that normal spiral galaxies give the dominant contribution to the total comoving IR energy density in the nearby universe, while, in contrast, the contribution from peculiar galaxies is only 39%.

关键词： galaxies evolution galaxies interactions galaxies starburst infrared galaxies galaxies luminosity function

Transformations and non-degenerate maps

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Science china Mathematics 2005年第z1期48卷 195-205页

作者： LI Baokui & WANG Yuefei Institute of Mathematics, academy of Mathematics and System sciences, chinese academy of sciences, Beijing 100080, china graduate school, chinese academy of sciences, Beijing 100080, china 1. Institute of Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences 100080 Beijing China 2. graduate school Chinese Academy of Sciences 100080 Beijing China

We shall prove the equivalences of a non-degenerate circle-preserving map and a M(o)bius transformation in ^Rn, of a non-degenerate geodesic-preserving map and an isometry in Hn of a non-degenerate line-preserving map and an affine transformation in Rn. That a map is non-degenerate means that the image of the whole space under the map is not a circle, or geodesic or line respectively. These results hold without either injective or surjective, or even continuous assumptions, which are new and of a fundamental nature in geometry.

关键词： M(o)bius transformation, circle-preserving map, non-degenerate map.

A novel operation mode for spaceborne polarimetric SAR

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Science china(Information sciences) 2011年第4期54卷 884-897页

作者： QI WeiKong 1,2 & YU WeiDong 1 1 Institute of Electronics,chinese academy of sciences,Beijing 100190,china 2 graduate school of chinese academy of sciences,Beijing 100039,china 1. Institute of Electronics Chinese Academy of Sciences Beijing 100190 China2. Graduate School of Chinese Academy of Sciences Beijing 100039 China

A novel operation mode for spaceborne polarimetric SAR,named polarization space-division adding polarization code-division (PSD-PCD) operation mode,is proposed in this paper through combining polarimetric SAR with elevation digital beam-forming (DBF) on *** a pulse repetition interval the up-chirp LFM sub-pulse is transmitted with horizontal polarization antenna,and with some delay the down-chip LFM subpulse is transmitted with vertical polarization antenna to realize code *** every sub-aperture receives returns from ground,SAR system uses range DBF to separate echoes relative to different sub-pulses in order to realize space *** system PRF is equal to that of single-polarization SAR,and elevation DBF help reduce range ambiguity ***,the main system parameters,including PRF,delay between two sub-pulses,radar equation and ambiguity are analyzed and compared with those of single-polarization *** results demonstrate the feasibility and validity of PSD-PCD operation mode.

关键词： spaceborne synthetic aperture radar (SAR) polarimetry digital beamforming (DBF) operation mode ambiguity ratio polarization space-division polarization code-division

Geometry of Broad Line Regions of Active Galactic Nuclei

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chinese Journal of Astronomy and Astrophysics 2008年第1期8卷 50-62页

作者： Xiao-Rong Lü1 Key Laboratory for Particle Astrophysics, Institute of High Energy Physics, chinese academy of sciences, Beijing 100049 2 graduate school of chinese academy of sciences, Beijing 100049 Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 and graduate school of chinese academy of sciences Beijing 100049

It has long remained an open question as to the geometry of the broad line region （BLR） in active galactic nuclei （AGNs）. The reverberation mapping technique which measures the response of the broad emission lines to the ionizing continuum, when combined with multiwavelength continuum fitted by sophisticated accretion disks, provides a way of probing the BLR geometry. We analyze a sample of 35 AGNs, which have been monitored by the reverberation mapping campaign. In view of energy budget, the reverberation-based BH masses are found to be in agreement with those obtained by accretion disk models in two thirds of the present sample while the reverberation mapping methods underestimate the BH masses in about one third of objects, as also suggested by CoUin et al. in a recent work. We point out that there are obviously two kinds of BLR geometry, which are strongly dependent on the Eddington ratio, and separated by the value LBol/LEdd - 0.1. These results prefer a scenario of the disk and wind configuration of the BLR and identify the Eddington ratio as the physical driver regulating the wind in the BLR.

关键词： accretion, accretion disks - galaxies active - galaxies Seyfert - quasars general

A Test on Different Types of the Time Curve of Hardness Ratio of Gamma-Ray Bursts based on the Curvature Effect

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chinese Journal of Astronomy and Astrophysics 2008年第4期8卷 451-464页

作者： Lan-Wei Jia National Astronomical Observatories/Yunnan Observatory,chinese academy of sciences,Kunming 650011,china graduate school of chinese academy of sciences,Beijing 100049,china National Astronomical Observatories/ Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China and graduate school of chinese academy of sciences Beijing 100049 China

We analyzed a sample of 66 gamma-ray bursts （GRBs） and statistically confirmed the prediction on the time curve of the hardness ratio of GRBs made by Qin et al. based on the curvature effect. In their analysis, GRB pulses are divided into three types according to the shape of their raw hardness ratio （RHR） time curves, defined as to include the background counts to the signal counts, so as to make use of counts within small time intervals. Of the three types, very hard sources exhibit a perfect pulse-like profile （type 1）, hard bursts possess a pulse-like profile with a dip in the decay phase （type 2）, and soft bursts show no pulse-like profile but have only a dipped profile （type 3）. In terms of the conventional hardness ratio, type 3 sources are indeed generally softer than those of type 1 and type 2, in agreement with the prediction. We found that the minimum value of RHR is sensitive in distinguishing the different types. We propose that GRB pulses can be classified according to the minimum value of RHR and that the different type sources may be connected with different strengths of the shock or/and the magnetic field.

关键词： gamma-rays burst -- gamma-rays observations - methods statistical

Effects of cosmological constant on motion of UHECR particles

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Science china(Physics,Mechanics & Astronomy) 2005年第1期48卷 44-56页

作者： CHEN Shaoxia & CHANG Zhe Institute of High Energy Physics, chinese academy of sciences, Beijing 100039, china graduate school of chinese academy of sciences, Beijing 100039, china Institute of High Energy Physics Chinese Academy of Sciences Beijing 100039 China graduate school Chinese Academy of Sciences Beijing 100039 China

Recent astronomical observations manifest that about two-thirds of the whole energy in the Universe is contributed by a small positive cosmological constant A (> 0). Then, an asymptotically de Sitter spacetime is premised naturally. However, physics in the de Sitter spacetime is very different from that in the Minkowski spacetime. As the first step, a covariant formalism of the kinematics in the de Sitter spacetime is presented here. By solving exactly the equations of motion for a field, we obtain the dispersion relation of a free particle. It is noticed that the dispersion relation is dependent on the degree of freedom of angular momentum of the particle. We show the threshold anomaly of the ultra high energy cosmic ray disappears naturally in the framework of the de Sitter kinematics.

关键词： ultrahigh energy cosmic ray, cosmological constant, curved spacetime.