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Spectral analysis of quasi-stationary sea surface topography from GRACE mission

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Science China Earth sciences 2005年第11期48卷 2040-2048页

作者： ZHANG Zizhan1,2.& LU Yang1,3 1. institute of Geodesy and Geophysics, chinese academy of sciences, Wuhan 430077, China 2. Graduate School of the chinese academy of sciences, Beijing 100039, China 3. Unite Center for Astro-geodymics Research, chinese academy of sciences, Shanghai 2.0030, China 1. institute of Geodesy and Geophysics Chinese Academy of Sciences 430077 Wuhan China 2. Graduate School of the chinese academy of sciences 100039 Beijing China 3. Unite Center for Astro-geodymics Research Chinese Academy of Sciences 200030 Shanghai China

During the last two decades satellite altimetry has offered an abundance of meas-urements of the sea surface resulting in the improvement of global mean sea surface height (MSSH) and marine geoid determination. On the other hand, with the launching of new genera-tion gravity satellites, some high accuracy long-wavelength gravity models are available. These breakthroughs give us a great opportunity for new estimation of quasi-stationary sea surface topography (QSST). In this paper, the new gravity model GGM01C derived from GRACE mission is briefly presented, and a new global high precision and high-resolution QSST is determined based on the GGM01C model and the global MSSH. The spectral features of the QSST esti-mated by GGM01C and EGM96 gravity model to degree/order 2.0 are discussed by spectral analysis. As a result, the QSST is mainly composed of long waves, medium waves partially and short waves scarcely, its power spectral structures are different between the zonal direction and the meridional direction, there are great differences between the two models, which maybe ex-plain why the ocean currents derived from the two gravity models by Tapley show different pat-terns.

关键词： quasi-stationary sea surface topography, mean sea surface height, GGM01, fast Fourier transform, spectral analysis

Energy distributions of the large-scale horizontal currents caused by wind in the baroclinic ocean

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Science China Earth sciences 2005年第12期48卷 2267-2275页

作者： ZHOU Lei1, TIAN Jiwei1 & WANG Dongxiao2.1. Physical Oceanography Laboratory, Ocean University of China, qingdao 2.6003, China 2. Key Laboratory of Tropical Marine Environmental Dynamics, South China Sea institute of {2., chinese academy of sciences, Guangdong 510301, China 1. Physical Oceanography Laboratory Ocean University of China 266003 Qingdao China 2. Key Laboratory of Tropical Marine Environmental Dynamics South China Sea Institute of Oceanology Chinese Academy of Sciences 510301 Guangdong China

Ocean current data for nearly 3 months in the South China Sea (SCS), combined with the NCEP/NCAR reanalysis wind data, are analyzed. The results indicate that the wind en-ergy enters the upper mixed layer in a wide continuous frequency band. In addition, the interac-tion between the low-frequency wind anomaly and the low-frequency current anomaly is the most ‘effective’ way for the energy input from the wind to the upper ocean. However, only the inertial and the near inertial energy propagate downwards through the upper mixed layer. The down-ward-propagating energy is distributed into the barotropic currents, the baroclinic currents and each mode of the baroclinic currents following the normal distributions. The energy change ratios between the barotropic motion to the baroclinic motion induced by the wind present a normal distribution of N (0.02.2. 0.3947). The energy change ratios of the first 4 baroclinic modes to the whole baroclinic currents also follow the normal distributions. The first baroclinic mode follows N (0.2.2., 0.1872., the second N (0.1979, 0.1504), the third N (0.1331, 0.1633), and the fourth N (0.0650, 0.1540), respectively.

关键词： wind anomaly, ocean current anomaly, energy transportation, wide frequency band, near-inertial fre-quency, energy distribution.

Mineralogy and crystal structure determination of Mg-fillowite

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Science China Earth sciences 2005年第5期48卷 635-646页

作者： MA Zhesheng 1 , SHI Nicheng 1 & YE Danian 2.1. China University of Geosciences, Beijing 100083, China 2. institute of Geology,{2., Beijing 10002., China 1. China University of Geosciences 100083 Beijing China 2. institute of Geology Chinese Academy of Sciences 100029 Beijing China

Accurate crystal structure determination of complex phosphate Mg-fillowite ? Na2.a(Mn4Mg2.e)7[PO4]6 has been finished. Mg-fillowite occurs in muscovite-pegmatite in the Altay area, Xinjiang, China. It is of the trigonal lattice, with space group R-3, unit cell a=1.5143(3) nm, c=4.3191(2. nm, V=8.5736 nm3, Z = 18. The R-factor of the determination accuracy is R (I > 2. ( I )) = 0.0776. The cationic polyhedra consist of two kinds of structural units: compound col- umn and screw column. In three-dimensional space, they are linked with each other through corner sharing or edge sharing to build the entire structure. There are 45 atoms in an asymmetric unit and 72. atoms in a unit cell. In terms of types and connection manners of the coordination polyhedra, the degree of complicity is rarely seen in all mineral crystal structures. Study of such a structure is significant for the classification of phosphate and the building rule of coordination polyhedra in a complex crystal structure.

关键词： Mg-fillowite, complex phosphate, crystal structure, coordination polyhedron.

A mathematical model for solid liquid and mass transfer coupling and numerical simulation for hydraulic fracture in rock salt

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Progress in Natural Science:Materials International 2005年第8期15卷 742-748页

作者： LIANG Weiguo 1,2. and ZHAO Yangsheng1(1. Mining Technology institute, Taiyuan University of Technology, Taiyuan 03002., China 2. Rock and Soil Mechanics institute,{2., Wuhan 430071, China) Mining Technology institute Taiyuan University of Technology Taiyuan 030024 China. Rock and Soil Mechanics institute Chinese Academy of Sciences Wuhan 43007! China

The hydraulic fracture in rock salt is a complicated solid fluid and mass transfer coupling process. Through theoretical analysis, a solid fluid and mass transfer coupling mathematical model of hydraulic fracture in rock salt is established in this work, and numerical simulations are carried out with the model. The simulation results indicate that rock salt cracks in the typical way of wing-crack(or tensile crack) during the fracture, and the relation of fracture aperture (w) with expanding distance (x) and fracture time (t) is w=(0.0034+0.0006t)e (0.0007+0.0018t)x. Furthermore, it has been found that both the water pressure in the crack and the expanding velocity of the crack decrease gradually as a result of the influence of salt dissolving during fracturing. These numerical simulations well illustrate the process of hydraulic fracture in rock salt and are significantly meaningful in engineering practice.

关键词： rock salt hydraulic fracture solid liquid and mass transfer coupling mathematical model numerical simulation.

Effect of concentration on surfactant micelle shapes——A molecular dynamics study

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Science China Chemistry 2005年第5期48卷 470-475页

作者： GAO Jian1,2. GE Wei1 & LI Jinghai1 1. Multiphase Reaction Laboratory, institute of Process Engineering, chinese academy of sciences, Beijing 100080, China 2. Graduate School of The chinese academy of sciences, Beijing 100085, China 1. Multiphase Reaction Laboratory Institute of Process Engineering Chinese Academy of Sciences 100080 Beijing China 2. Graduate School of The chinese academy of sciences 100085 Beijing China

Many aspects of the behavior of surfactants have not been well understood due to the coupling of many different mechanisms. Computer simulation is, therefore, attractive in the sense that it can explore the effect of different mechanisms separately. In this paper, the shapes, structures and sizes of sodium dodecylbenzenesulfonate (SDBS) micelles under different con-centrations in an oil/water mixture were studied via molecular dynamics (MD) simulations using a simplified atomistic model which basically maintains the hydrophile and lipophile properties of the surfactant molecules. Above the critical micellar concentration (cmc), surfactant molecules ag-gregate spontaneously to form a wide variety of assemblies, from spherical to rodlike, wormlike and bilayer micelles. Changes in their ratios of the principle moments of inertia (g1/g3, g2.g3) in-dicated the transition of micelle shapes at different concentrations. The aggregation number of micelle is found to have a power-law dependence on surfactant concentration.

关键词： surfactant, MD simulation, sodium dodecylbenzenesulfonate, micelle shape.

Debris Flow Hazard Assessment Based on Support Vector Machine

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Wuhan University Journal of Natural sciences 2006年第4期11卷 897-900页

作者： YUAN Lifeng 1, 2., ZHANG Youshui 3 1. institute of Mountain Hazards and Environment, chinese academy of sciences, Chengdu 610041, Sichuan, China 2. Graduate University of chinese academy of sciences, Beijing 100049, China 3. institute of Geographical sciences and Natural Resources Research, chinese academy of sciences, Beijing 100101, China institute of Mountain Hazards Environment Chinese Academy of Sciences 610041 Chengdu Sichuan China Graduate University of chinese academy of sciences 100049 Beijing China institute of Geographical sciences Natural Resources Research Chinese Academy of Sciences 100101 Beijing China

Seven factors, including the maximum volume of once flow , occurrence frequency of debris flow , watershed area , main channel length , watershed relative height difference , valley incision density and the length ratio of sediment supplement are chosen as evaluation factors of debris flow hazard degree. Using support vector machine （SVM） theory, we selected 2.9 basic data of 37 debris flow channels in Yunnan Province as learning samples in this study. We create a debris flow hazard assessment model based on SVM. The model was validated though instance applications and showed encouraging results.

关键词： debris flow hazard assessment support vector machine (SVM)

A new spceies of N assarius(Gastropoda,Nassariidae)from the northern China seas

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Acta Oceanologica Sinica 2011年第6期30卷 82-85页

作者： YANG Jingwen ZHANG Suping institute of oceanology Chinese Academy of Sciences Qingdao 266071 China Graduate University of chinese academy of sciences Beijing 10049 China

A new species, Nassarius （Zeuxis） humeratus n. sp. of Nassariidae was described based on the specimens collected in the Huanghai Sea （Yellow Sea） and Bohai Sea during the expedition from 1958 to 1959. The new species was distinguished from similar species Nassarius （Zeuxis） bolangoi （Ladd, 1976） and Nassarius （Varicinassa） variciferus （A. Adams, 1852. in shell characteristics. Some relative discussion was provided. The new species mainly distributes in the subtidal zone of 30–53 m depth, in muddy and sandy bottom in the Bohai Sea and northern Huanghai Sea.

关键词： Gastropoda Nassariidae new species Bohai Sea Huanghai Sea

Impact of germanium on the growth of Psuedonitzschia pungens f. multiseries and the production of algal toxin

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chinese Science Bulletin 1998年第24期43卷 2091-2095页

作者： YU Zhiming+1 and D. V. Subba Rao+2.1. institute of oceanology,{2., qingdao 2.6071, China 2. Bedford institute of Oceanography, P. O. Box 1006, Dartmouth, N. S., Canada B2. 4A2 institute of oceanology Chinese Academy of Sciences Qingdao China Bedford institute of Oceanography Dartmouth Canada

The impacts of germanic acid Ge(OH)-4 on the growth of Psuedonitzschia pungens f. multiseries and on the production of the algal toxin, domoic acid, were studied. The results showed that germanic acid in the range of concentrations could inhibit the growth of the algal cells and the inhibition was enhancing with the concentrations of germanic acid increasing. Germanic acid also could inhibit the production of the algal toxin, domoic acid in cells and the inhibition reached up to 100% at Ge/Si=35. Based on the results, the mechanism was discussed.

关键词： germanium red tide organism domoic acid inhibition.

Digital image analysis of palaeoenvironmental records and applications

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chinese Science Bulletin 2002年第23期47卷 1957-1963,2025-2026页

作者： SUN Donghuai1,2. LIU Yu2.& TAN Ming31. South China Sea institute of oceanology,{2.. Guangzhou 510301, China 2. State Key Laboratory of Loess and Quaternary Geology, Earth Environmental institute,{2., Xi’an 710075, China 3. institute of Geology and Geophysics,{2., Beijing 10002., China South China Sea institute of oceanology Chinese Academy of Sciences Guangzhou China State Key Laboratory of Loess and Quaternary Geology Earth Environmental Institute Chinese Academy of Sciences Xi’an China institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

Environmental change signals in geological or biological records are commonly reflected on their reflecting or transmitting images. These environmental signals can be extracted through digital image analysis. The analysis principle involves section line selection, color value reading and calculating environmental proxy index along the section lines, layer identification, auto-chronology and investigation of structure evolution of growth bands. On detailed illustrations of the image technique, this note provides image analyzing procedures of coral, tree-ring and stalagmite records. The environmental implications of the proxy index from image analysis are accordingly given through application demonstration of the image technique.

关键词： digital image environmental records.