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Validating global hydrological models by ground and space gravimetry

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chinese Science Bulletin 2009年第9期54卷 1534-1542页

作者： ZHOU JiangCun1,2.3. SUN HePing1,2.& XU JianQiao1,2.1{3., chinese academy of sciences,{2., China 2.key laboratory of dynamic geodesy, chinese academy of sciences,{2., China 3.{13. University of chinese academy of sciences, beijing 100049, China institute of geodesy and {2. Chinese Academy of Sciences Wuhan China key laboratory of {2. {3. Chinese Academy of Sciences Wuhan China graduate University of chinese academy of sciences Beijing China

The long-term continuous gravity observations obtained by the superconducting gravimeters (SG) at seven globally-distributed stations are comprehensively analyzed. After removing the signals related to the Earth's tides and variations in the Earth's rotation, the gravity residuals are used to describe the seasonal fluctuations in gravity field. Meanwhile, the gravity changes due to the air pressure loading are theoretically modeled from the measurements of the local air pressure, and those due to land water and nontidal ocean loading are also calculated according to the corresponding numerical models. The numerical results show that the gravity changes due to both the air pressure and land water loading are as large as 100×10-9 m s-2.in magnitude, and about 10×10-9 m s-2.for those due to the nontidal ocean loading in the coastal area. On the other hand, the monthly-averaged gravity variations over the area surrounding the stations are derived from the spherical harmonic coefficients of the GRACE-recovered gravity fields, by using Gaussian smoothing technique in which the radius is set to be 600 km. Com-pared the land water induced gravity variations, the SG observations after removal of tides, polar mo-tion effects, air pressure and nontidal ocean loading effects and the GRACE-derived gravity variations with each other, it is inferred that both the ground- and space-based gravity observations can effec-tively detect the seasonal gravity variations with a magnitude of 100×10-9 m s-2.induced by the land water loading. This implies that high precision gravimetry is an effective technique to validate the re-liabilities of the hydrological models.

关键词：重力测量水文模型模型验证和空间地面重力变化季节性波动空气压力

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, {2. of High Energy Physics,{3., beijing 100049 2.graduate school of{3., beijing 100049 key laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 graduate school of{2. 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 3. 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

Sea level variations in the South China Sea inferred from satellite gravity,altimetry,and oceanographic data

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Science China Earth sciences 2012年第10期55卷 1696-1701页

作者： FENG Wei 1,2.ZHONG Min 1,3.& XU HouZe 1,3.1 State key laboratory of {2. and Earth’s {2.s,institute of {2. and geophysics,chinese academy of sciences,wuhan 4.0077,China 2.{12. University of chinese academy of sciences,beijing 100049,China 3.institute of geophysics,Huazhong University of Science and Technology,wuhan 43.074,China State key laboratory of {2. and Earth’s {3.s Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China graduate University of chinese academy of sciences Beijing China institute of geophysics Huazhong University of Science and Technology Wuhan China

Sea level variations(SLVs) can be divided into two major components:the steric SLV and the mass-induced *** two components of SLV in the South China Sea(SCS) are studied by using satellite altimetry,GRACE(Gravity Recovery and Climate Experiment) satellite gravity,and oceanographic data on annual and inter-annual *** the annual timescale,the geographic distribution of mass-induced SLV's amplitude jointly estimated from altimetry and the ECCO(Estimation of the Circulation and Climate of the Ocean) model agrees very well with that from *** observes obvious seasonal mass-induced SLV in the SCS with annual amplitude of 2.7±0.4 cm,which is consistent with the annual amplitude of 2.7±0.3.cm estimated from the steric-corrected *** the inter-annual timescales,the mean SLV in the SCS shows a large oscillation,which is mainly caused by the steric *** trend of mean SLV inferred from altimetry in the SCS is 5.5±0.7 mm/yr for the period of 1993.2.09,which is significantly higher than the global sea level rise rate of 3.3.0.4 mm/yr in the same *** is no obvious trend signal in the mass-induced SLV detected from GRACE that indicates the water exchange between the SCS and its adjacent seas and land is in balance within the study period.

关键词： altimetry GRACE ECCO the South China Sea sea level variation

Molecular identification of species in Prunus sect. Persica (Rosaceae), with emphasis on evaluation of candidate barcodes for plants

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Journal of Systematics and Evolution 2011年第2期49卷 138-145页

作者： 1,2.Xu QUAN 1 Shi-Liang ZHOU 1 (State key laboratory of Systematic and Evolutionary Botany, {2. of Botany,{2., beijing 100093. China) 2.(graduate school of the{2., beijing 100049, China) (State key laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (graduate school of the{2. Beijing 100049 China)

Species of Prunus L. sect. Persica are not only important fruit trees, but also popular ornamental and medicinal plants. Correct identification of seedlings, barks, or fruit kernels is sometimes required, but no reliable morphological characters are available. Nowadays, the technique of DNA barcoding has the potential to meet such requirements. In this study, we evaluated the suitability of 11 DNA loci (atpB-rbcL, trnH-psbA, trnL-F, trnS-G, atpF-H, rbcL, matK, rpoB, rpoC1, nad1, and internal transcribed spacer [ITS]) as candidate DNA barcodes for peaches, using samples from 3. populations, covering all the species in sect. Persica. On the whole, the primers worked well in this group and sequencing difficulties were met only in the case of ITS locus. Five loci (rbcL, matK, rpoB, rpoC, and nad1) have very low variation rates, whereas atpB-rbcL, atpF-H, trnH-psbA, trnL-F and trnS-G show more variability. The most variable loci, atpB-rbcL and trnH-psbA, can distinguish three of the five species. Two two-locus combinations, atpB-rbcL+trnL-F and atpB-rbcL+atpF-H, can resolve all five species. We also find that identification powers of the loci are method-dependent. The NeighborNet method shows higher species identification power than maximum parsimony, neighbor joining, and unweighted pair group method with arithmetic mean methods.

关键词： atpB-rbcL DNA barcode Prunus sect. Persica trnL-F.

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,{2., China 2.3., chinese academy of sciences, wuhan 4.0077, 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 {2. Chinese Academy of Sciences Wuhan China State key laboratory of Astronautic {2.s 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

Elemental and isotopic compositions of the hydrothermal sulfide on the East Pacific Rise near 13.N

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Science China Earth sciences 2010年第2期53卷 253-266页

作者： ZENG ZhiGang1,CHEN DaiGeng1,2.YIN XueBo1,WANG XiaoYuan1,ZHANG GuoLiang1,2.& WANG XiaoMei1,2.1 Seafloor Hydrothermal Activity {3. of the key {3. of Marine Geology and Environment,{2. of Oceanology,chinese academy of sciences,Qingdao 2.6071,China 2.graduate {13. of chinese academy of sciences,beijing 100049,China Seafloor Hydrothermal Activity laboratory of the key laboratory of Marine Geology and Environment Institute of Oceanology Chinese Academy of Sciences Qingdao China graduate school of{2. Beijing China

The mineralogical,elemental,and isotopic characteristics of a hydrothermal sulfide sample from one dredge station (12.42.3.’N,103.54.48’W,water depth 2.55 m) on the East Pacific Rise near 13.N were *** hydrothermal sulfide was composed mainly of sphalerite,chalcopyrite,and pyrite and was a Zn-rich sulfide;in layer ep-s-1,goethite formed by secondary oxidation was *** concentrations of rare elements,such as Li (0.15×10-6-0.3.×10-6),Be (0.01×10-6-0.05×10-6),Zr (73.8×10-9-13.4×10-9),Nb (8.14×10-9-64.7×10-9),Hf (2.54×10-9-2..0×10-9),and Ta (0.2.3.10-9-1.2.×10-9),were far lower in the hydrothermal sulfide than in the ocean crust,whereas the content of Au was higher and the contents of Co,Ni,Sr,Cs,Ba,Bi,and U were *** correlations between Zn and Cr,Cd and Ga,Cu and P,P and In (R2.> 0.8) were positive,whereas those between Zn and Fe,Cu,and Ba (R2.> 0.8) were distinctly *** low-temperature mineral assemblages to high-temperature mineral assemblages,the spatial distributions of dispersive and rare elements (***,Li,Cs) in the hydrothermal sulfide displayed corresponding *** variations observed in some elements (e.g.,Cd,Cs,P) are controlled by Zn,Fe,and Cu sulfides,*** weathering accounts for the enrichment of V,Mn,and rare earth elements (REE) in the henna sulfide-oxidation layer that bears the secondary oxide mineral,leading to identical REE patterns for this layer (ep-s-1) and *** weathering also distinctly affects the correlations between the element ratios of the hydrothermal *** high-temperature mineral assemblages to low-temperature mineral assemblages,Fe content and δ 3.S value of the hydrothermal sulfide increase gradually,and Zn content and lead isotopic ratios decrease gradually on the contrary,which indicate the influences of seawater on elements and the sulfur and lead isotopic compositions enhance gradually during the formation of hydrothermal sulfides.

关键词： variation element isotopic composition hydrothermal sulfide East Pacific Rise 13.N

Identification of high-lipid producers for biodiesel production from forty-three green algal isolates in China

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Progress in Natural Science:Materials International 2011年第4期21卷 269-276页

作者： An-yue LIU~(1,2.,Wei CHEN~1,Ling-ling ZHENG~1,Li-rong SONG~1 1.State key laboratory of Freshwater Ecology and Biotechnology,{2. of Hydrobiology,{2.,wuhan 43.072.China 2.graduate school,chinese academy of sciences,{13. 100049,China State key laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China graduate school Chinese Academy of Sciences Beijing 100049 China

To identify some desirable algal strains for our future research and/or the production of algae-based biofuel,43.green algal strains were successfully isolated from chinese freshwaters,and then incubated in the laboratory bioreactors for the growth and oil accumulation *** a 15 d incubation experiment,the accumulations of their biomass and total lipids,together with the lipid productivities for these green algal strains were systematically investigated and *** indicated that the accumulations of biomass for the 43.algal strains ranged from 0.53.g/L to 6.07 g/L during the experiments,with the highest biomass of 6.07 g/L for green algae Scenedesmus *** lipid content for the tested algal strains varied from 2.%to 51%of the dry biomass at the end of cultivation *** algae Chlorella pyrenoidosa was one of the best oil producers based on our investigations,with the total lipid content of 51%of dry *** the growth rates and the accumulations of intracellular lipids into the consideration,10 strains were considered to have significant potential for biofuel *** addition,the lipid productivities of the selected strains were further investigated.

关键词： biofuel microalgae lipid accumulation

Morphological characteristics of leaf epidermis and size variation of leaf,flower and fruit in different ploidy levels in Buddleja macrostachya (Buddlejaceae)

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Journal of Systematics and Evolution 2009年第3期47卷 231-236页

作者： 1,2.ao CHEN 1Wei-Bang SUN 3.ang SUN 1(Kunming Botanical Garden, Kunming institute of Botany, chinese academy of sciences, Kunming 6502.4, China) 2.{2. school of chinese academy of sciences, beijing 100049, China) 3.key laboratory of Biodiversity and Biogeography, Kunming institute of Botany, chinese academy of sciences, Kunming 6502.4, China) (Kunming Botanical Garden Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China) (graduate school of{2. Beijing 100049 China) (key laboratory of Biodiversity and Biogeography Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China)

Buddleja macrostachya (Buddlejaceae) is a widespread shrub native to the Sino-Himalayan mountains and beyond. It has been found to occur at two ploidy levels, hexaploid, 2.=6x=114 and dodecaploid, 2.=12.=2.8. To determine if morphological characters might be used as indicators of ploidy levels, we measured floral and fruit length, relative and absolute leaf size, trichome density on both leaf surfaces, and stomatal density and length in different populations of B. macrostachya. In general, flower and fruit length, absolute leaf size, and stomatal length increased with an increase at ploidy level (P0.05) in different populations. Other characters studied such as trichome type, cuticular membrane and ornamentation of stomata, cell and stomatal shape, and anticlinal wall pattern were quite constant in this species. Thus it appears that flower and fruit length, absolute leaf size, and stomatal frequency and length can be used to distinguish hexaploid from dodecaploid cytotypes either in the fleld or in herbarium specimens.

关键词： Buddleja macrostachya dodecaploid hexaploid leaf epidermis ploidy level stomata.

Depside salts from Salvia miltiorrhiza improve myocardial microperfusion in rats using laser Doppler flowmetry

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Acta Pharmacologica Sinica 2007年第6期28卷 789-795页

作者： Xiao-fen LI~(2.3.,Yi-ping WANG~(2.4)~2.State {3. laboratory.of Drug Research,Shanghai {2. of Materia Medica,Shanghai {2.s for Biological sciences,chinese academyof sciences,Shanghai 2.12.3.China,~3.{13. school of chinese academy of sciences,beijing {12.,China State key laboratory of Drug Research Shanghai Institute of Materia Medica Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China graduate school of{2. Beijing China

Aim:To investigate the effects of depside salts from Salvia miltiorrhiza on myo-cardial microperfusion and systemic hemodynamics in open-chest anaesthetizedSprague-Dawley ***:Myocardial microperfusion was measured bylaser Doppler flowmetry with a needle probe;cardiac output (CO) was determinedusing ultrasonic Doppler *** hemodynamic parameters,includingfemoral artery blood pressure,cardiac inotropy,and systemic vascular resistance(SVR) were simultaneously recorded by the PowerLab ***:Intrave-nous administration of S miltiorrhiza depside salts resulted in a significant imme-diate increase in CO and cardiac inotropy,but a fall in SVR.S miltiorrhiza depsidesalts (3. mg/kg and 60 mg/kg) promoted cardiac index (CI) by 12.2.±6.3. (P2..1%±3.5% (P3.±2.9% (P3. mg/kgand 60 mg/kg S miltiorrhiza depside salts,***:Theseresults indicated that S miltiorrhiza depside salts improved myocardial micro-perfusion,as well as CO.

关键词： lithospermate B myocardial microperfusion laser Doppler flowmetry cardiac output ultrasonic Doppler flowmetry