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The Dabieshan Coesite-bearing Eclogite Terrain-A Late Archaean Ultra - high- Pressure Metamorphic Belt

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Acta Geologica Sinica(English Edition) 1996年第1期70卷 46-58页

作者： Cao Ronglong and Zhu Shouhuaguangzhou institute of {2., chinese academy of sciences, guangzhou, Guangdong guangzhou institute of {2. Chinese Academy of Sciences Guangzhou Guangdong

A U -Pb zircon age of 2.74±2. Ma for eclogite from the Bixiling rock body of Anhui Province, central china, indicates that the Dabieshan coesite-bearing eclogite was probably formed in the Late Archaean. A phengite Ar-Ar isochron age of 662.13 Ma for the eclogite confines also an upper limit age of its subsequent retrograde metamorphism in the Precambrian. The results of isotopic dating for such type of eclogite coincide with the geological features of its restricted occurrence within the Archaean metamaorphic terrain composed of the Dabie Group. It is believed that the Dabieshan coesite-bearing eclogite terrain might be a Late Archaean ultra-high-pressure metamorphic belt. The Dabie Mountains area was the eastward extension of the southern Qinling structural belt during the Triassic. Both the Dabie Group and the coesite-bearing eclogite hosted therein underwent a late-stage dynamic metamorphic event. The present authors have obtained a muscovite Ar-Ar isochron age of 192.6±2.8 Ma from plagioclase gneiss and a hornblende Ar-Ar plateau age of 2.0.7±4.6 Ma for the low amphibolite in eclogite respectively, which represent the Indosinian reworking ages of the original metamorphic rocks of the Dabie Group gneiss and coesite-bearing eclogite.

关键词： Dabie Mountains coesite-bearing eclogite zircon U -Pb dating Late Archaean ultra-high-pressure metamorphic belt

Effects of crystallization fractions on mechanical properties of Zr-based metallic glass matrix composites

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Science china(Physics,Mechanics & Astronomy) 2010年第3期53卷 424-429页

作者： QIU ShengBao1,2. YAO KeFu1 & GONG Pan1 1 KLAMPT, Department of Mechanical Engineering, Tsinghua University, Beijing 100084, china 2.institute of Industry Technology, {2. & chinese academy of sciences, {2. 511458, china KLAMPT Department of Mechanical Engineering Tsinghua University Beijing China institute of Industry Technology Guangzhou & Chinese Academy of Sciences Guangzhou China

The Zr41Ti14Cu12.5Ni10Be2..5 (at.%) bulk metallic glass composites with various crystallization fractions were prepared by pretreating the bulk metallic glassy samples with pulsing current, and then by isothermal annealing at near initial crystallization temperature for different periods of time. The precipitations and crystallization fractions were studied by X-ray diffraction (XRD) and differential scanning calorimetry (DSC), and their effects on mechanical properties of the composite were studied by microhardness, uniaxial compression test and scanning electron microscopy (SEM). The experimental results show that the primary precipitate is quasicrystalline phase and other metastable phases including Be2.r, Zr2.u and FCC would precipitate subsequently. In the initial crystallization process, in which the crystallization fraction increases from 0 to 8.2., both fracture strength and plastic strain increase, with the maximum plastic strain up to 6.4%. When the crystallization fraction is larger than 8.2., the fracture strength and the plastic strain decrease sharply. Furthermore, the alloy with low crystallization fraction is fractured by shearing, while for high crystallization fraction it is fractured by splitting and cleavage. The results show that the mechanical properties of the glassy alloy could be optimized by controlling the processing parameters.

关键词： bulk metallic glass pulsing current crystallization fraction plasticity shear band

EFFECT OF MAGNETIZATION OF WATER ON INDUCTION TIME AND GROWTH PERIOD OF NATURAL GAS HYDRATE

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化工学报 2003年第Z1期54卷 81-85页

作者： KUANG Li and FAN Shuanshi(guangzhou institute of Energy Conversion,{2., guangzhou 510070, Guangdong, china) guangzhou institute of Energy Conversion Chinese Academy of Sciences Guangzhou 510070 Guangdong China

The effect of diluted solution's magnetization on induction time and growth period of natural gas hydrate (NGH) has been investigated in quiescent reaction system at pressure of 4. 5 MPa and temperature of 2.4 K with SDS as surfactant, by using volume fixed and pressure falling method. Experimental results show that magnetization will have effect on the induction time of NGH. After magnetization with magnetic field intensity of 0.33 T, the induction time of NGH has been reduced to 47 min (average) from 99 min (average) in which there is no magnetization. On the other hand, the induction time has been prolonged after magnetization of the diluted solution with magnetic field intensity of 0.05 T, 0. 11 T, 0.2. T, 0.44T. Especially with magnetic field intensity of 0.11 T, the induction time had even been prolonged to 431min (average). The effect of magnetization on the growth period of NGH has not been found at the experimental condition.

关键词： natural gas hydrate, magnetization, growth, induction time

Adsorption of Environmental Pollutants on Pillared Montmorillonite

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Pedosphere 2001年第2期11卷 159-166页

作者： WUPINGXIAL GUOJIUGAO 等 DepartmentofEnvironmentalScienceandEngineering SouthChinaUniversityofTechnologyGuangzhou510640（China） guangzhouinstituteof{2. theChineseAcademyofSciencesGuangzhou510640（

Both inorganic and organic pillared montmorillonites were used to adsorb phenol. Batch kinetics and isotherm studies were carried out to evaluate the effect of equilibrium time and pH on adsorption of phe- nol by montmorillonites and re-adsorbing characteristics of pillared montmorillonites. The adsorption of phenol increased with increasing solution pH values. The elimination ratio of phenol from the solution by the absorption of organic modified pillared montmorillonite (OrPMt) reached equilibrium quickly after vibrating for 5 minutes. Meanwhile for organic montmorillonite (OrMt), pillared montmorillonite (PMt) and montmorillonite (Mt), the time to reach phenol-absorption equilibrium were 2., 30 and 90 minutes, respectively. The adsorbing capacity of the pillared montmorillonite modified with surfactant improved greatly. The phenol-adsorbing capacity of pillared molltmorillonites mainly depended on microporous structure and surface component of the modified clays. After calcination at 500 ℃, the pillar structure and the basal spacing (1.83 um) were still stable. So the pillared montmorillonite could be recycled, and it was a potential material for adsorbing environmental pollutants.

关键词： adsorption phenol pillared montmorillonite

A preliminary analysis on lithospheric thickness and crustal ages in central basin of South china Sea

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Acta Oceanologica Sinica 1997年第1期16卷 85-107页

作者： Chen Xue and Lin Jinfeng South china Sea institute of Oceanology, the{2., guangzhou 510301, china South china Sea institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China

The models about lithospheric thickness and thermal conduction inside the lithosphere and the top layer of the asthenosphere have been proposed in this study for four type regions: the midoceanic ridge, the extinct spreading ridge, the lithospheric fault fissure and the mouth of the extinct submarine volcanoes which are in deep sea bottom. The solutions of the models are found to be the same. The formulas of temperature distribution inside the lithosphere and the top layer of the asthenosphere, the lithospheric thicknesses to the heat flow and the crustal ages to the heat flow are obtained. The crustal ages and the lithospheric thicknesses of the central basin are calculated. And they are used to draw the lithospheric thicknesses and crustal ages maps of the central basin (in this paper both the central basin and the basin are the central basin of the South china Sea). According to their characteristics, the central basin is divided into three regions. The lithospheric thicknesses, crustal ages and heat flow distribution characteristics are discussed respectively. The formation and evolution of the South china Sea are analysed and it is thought that the South china Sea has undergone three episode-seafloor spreadings.

关键词： Thermal conduction equation lithospheric thickness crustal age evolution

Distribution of moretene,sterere,fernene,hopene and dienoic carboxylic acid in marine sediments in sea area of the Southern Ocean

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Acta Oceanologica Sinica 1993年第2期12卷 237-247页

作者： Jiang Shanchun and Tang Yunqian institute of geochemistry, {2. Branch, Academia Sinica, guangzhou 510640, china Second institute of Oceanography, State Oceanic Administration, Hangzhou 310012. china

The soluble organic matters were extracted from marine sediments in the sea area of Southern Ocean by using organic solvents. The hydrocarbon and carboxylic acid fractions were separated with the thin layer chromatography. The organic compounds of 170(H), 2.α(H)- bishomomoretene, cholest - 5 - ene, 2. - methyl - cholestene, 2. - ethylcholestene, hop-17(2.)-ene, neohop - 13(18)-ene, fern-8-ene, fern-7-ene, 170(H), 2.0 (H) - hop - 2.(2.)-ene (diplotene), steranes, β, β-hopanes C2. -C31 and unsaturated carboxylic acids C18:2.9.12., C18:1Δ9,C18:1Δ11 , have been identi-fied in the hydrocarbon and carboxylic acid fractions by means of gas chromatography and gas chromatography - mass spec-trometry - data system. The distributions of 3, a - bishomomoretene, β,β- hopene and β,β- hopane are characteristic of immature organic matter. The sterane, C2. 2.S/2.R epimer ratio 0. 6 indicate that the organic matter had experienced a thermal evolution in the early sedimentation. The unsaturated fatty acids especially dienoic acids and fernene compounds indicate not only the origin from autochthonous bacteria but also the reducing environment in the Southern Ocean.

关键词： Lipids diplotene moretene sterene fernene dienoic cacboxylic acid

RAZUMIKHIN-TYPE THEOREMS FOR ASYMPTOTIC STABILITY OF IMPULSIVE STOCHASTIC FUNCTIONAL DIFFERENTIAL SYSTEMS

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Journal of Systems Science and Systems Engineering 2010年第1期19卷 72-84页

作者： Pei CHENG~1 Feiqi DENG~2.Xisheng DAI~3 Systems Engineering institute,South china University of Technology,{2. 510640,china Systems Engineering institute South China University of Technology Guangzhou China

In this paper, we investigate the pth moment uniformly asymptotic stability of impulsive stochastic ftmctional differential systems by extending some Razumikhin-type theorems. Based on the Lyapunov functions and Razumikhin techniques, some criteria are established and their applications to impulsive stochastic delay systems are proposed. An illustrative example shows the effectiveness of our results.

关键词： Stochastic functional differential systems Impulse Razumiltial theorems Asymptotic stability

Low genetic diversity of symbiotic dinoflagellates(Symbiodinium) in scleractinian corals from tropical reefs in southern Hainan Island,china

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Journal of Systematics and Evolution 2011年第6期49卷 598-605页

作者： 1,2.Guo-Wei ZHOU 1,2.ui HUANG 1(Key Laboratory of Marine Bio-resources Sustainable Utilization,South china Sea institute of Oceanology,{2. academy of sciences,guangzhou 510301,china) 2.Tropical Marine Biological Research Station in Hainan,{2. academy of sciences,Sanya 572.00,china) (Key Laboratory of Marine Bio-resources Sustainable Utilization South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China) (Tropical Marine Biological Research Station in Hainan Chinese Academy of Sciences Sanya 572000 China)

Endosymbiotic dinoflagellates in the genus Symbiodinium are among the most abundant and important group of photosynthetic protists found in coral reef *** order to further characterize this diversity and compare with other regions of the Pacific,samples from 44 species of scleractinian corals representing 2. genera and 9 families,were collected from tropical reefs in southern Hainan Island,*** gradient gel electrophoresis fingerprinting of the ribosomal internal transcribed spacer 2.identified 11 genetically distinct Symbiodinium types that have been reported *** majority of reef-building coral species(88.6%)harbored only one subcladal type of symbiont,dominated by host-generalist C1 and C3,and was influenced little by the host’s apparent mode of symbiont *** species harbored more than one clade of Symbiodinium(clades C,D)*** geographically isolated from the rest of the Pacific,the symbiont diversity in southern Hainan Island was relatively low and similar to both the Great Barrier Reef and Hawaii symbiont assemblages(dominated by clade C Symbiodinium).These results indicate that a specialist symbiont is not a prerequisite for existence in remote and isolated areas,but additional work in other geographic regions is necessary to test this idea.

关键词： coral dinoflagellate diversity South china Sea Symbiodinium.

TECTONO-SEDIMENTARY EVOLUTION OF THE TERTIARY BASINS IN EASTERN TIBET: CONSTRAINING THE RAISING OF TIBETAN PLATEAU

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地学前缘 2000年第S1期7卷 287-288页

作者： Zhou Jiangyu\+1, Wang Jianghai\+1, Yin An\+2.Brian Horton\+3, Matthew Spurlin\+2.WT5,5”BX](1 guangzhou institute of {2., chinese academy of sciences, Wushan, guangzhou 510640,china 2.Department of Earth and Space sciences and institute of Geo

The Tertiary basins are distributed in the eastern margin of the Tibetan Plateau along the large\|scale arc\|shaped strike\|slip belt of the Qiangtang—Hengduan Shan—Jinshajiang—Red River belt. Most of basins were controlled by regional northwest\| and south\|north treading faults, and a few basins were constrained by northwest\| or north\|north\|east\|treading local *** detailed field mapping and sedimentologic observations for 6 typical Tertiary basins in eastern Tibet show that their types include depressive basins, rifting basins, pull\|apart and extensional basins related to strike\|slip faulting, and erosion\|residual basins. Recently, most of them are controlled by compression\| or thrust\|related margin faults in single side or double laterals of these basins. Not\|well\|developed strata in the Tertiary basins were deformed to form various tight folds and thrusts. High\|K magma intruded widely into the basins. The tectono\|sedimentary evolution of the Tertiary basins appears tempo\|spatially inhomogeneous. The preliminary model to interpret the Tertiary basin evolution is described as below.

关键词： Tertiary basins Sedimentology Tibet raising Eastern T ibet