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Acta Geochimica 2006年第S1期 189-190页

作者： Jun LI1, Gan ZHANG1, Shihua QI2. Lingli GUO1, Xianzhi PENG1 1 State Key Laboratory of geochemistry, guangzhou Institute of geochemistry, chinese academy of sciences, guangzhou 510640, china 2.School of Environmental sciences, china University of Geosciences, Wuhan 430074, china

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, chinese academy of sciences. {2. 510301, china 2. State Key Laboratory of Loess and Quaternary Geology, Earth Environmental Institute, chinese academy of sciences, Xi’an 710075, china 3. Institute of Geology and Geophysics, chinese academy of sciences, 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.

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, guangzhou & {2., guangzhou 511458, china 1. KLAMPT Department of Mechanical Engineering Tsinghua University Beijing 100084 China2. Institute of Industry Technology Guangzhou & Chinese Academy of Sciences Guangzhou 511458 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

Thermodynamic Modelling of Ore-Forming Mechanism of the Changkeng Gold-Silver Deposits in Guangdong Province

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Acta Geologica Sinica(English Edition) 1997年第4期71卷 433-445页

作者： Zhang Sheng, Li Tongjin and Wang Liankuiguangzhou Institute of geochemistry, {2.Wushan, guangzhou 510640 guangzhou Institute of geochemistry Chinese Academy of Sciences Wushan Guangzhou 510640 [?]Zhang Sheng Born in 1967 graduated from china University of Geosciences (Wuhan) in 1989 and acquired the master's and doctor's degrees in {2. (CAS) and Guangdong Institute of geochemistry CAS in 1992 and 1996 successively. He is now engaged in studies of metallic ore deposits geochemical thermodynamics and experimental geochemistry.

The Changkeng gold-silver deposits consist of a sediment-hosted, disseminated gold deposit and a replacement-type silver deposit. The mineralizations of gold and silver are zoned and closely related to the silicification of carbonate and clastic rocks, so that siliceous ores dominate in the deposit. The mineralizing temperature ranges mainly from 300 to 170℃, and K+, Na+, Ca2., Mg2., and Cl- are the major ions in the ore-forming fluid. Calculations of distribution of metal complexes show that gold is mainly transported by hydrosulphide complexes, but chloride complexes of silver, iron, lead, and zinc, which are transformed into hydroxyl and hydrosulphide complexes under neutral to weak-alkaline circumstances in the late stage, predominate in the ore-forming solutions. Water-rock interaction is confirmed to be the effective mechanism for the formation of silver ores by computer modelling of reaction of hydrothermal solution with carbonate rocks. The solubility analyses demonstrate that the precipitation of gold and silver-bearing minerals taking place under weak-acid conditions and near-neutral to weak-alkaline conditions, respectively, is the main or favourable factor for the ore zonation and separation between gold and silver.

关键词： computer modelling transport form of element water-rock interaction mineral precipitation gold-silver deposit Guangdong province

Wave Loads and Protective Techniques of An On-Shore Wave Power Device

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china Ocean Engineering 1995年第4期10卷 455-464页

作者： You YageYuZhi Associated Professor, guangzhou Institute of Energy Conversion, chinese academy of sciences,guangzhou 510070. Professor, guangzhou Institute of Energy Conversion, chinese academy of sciences, guangzhou 510070

In this paper, the extreme wave loads on an on-shore wave power device are investigated. First, boundary element method is applied to solve the three dimensional potential problem based on the small amplitude wave assumption. Then the motion of the Oscillating Water Column (OWC) inside the device and its laods on the device are calculated in time domain. Several protective techniques often applied are simulated by changing the constraint of the upper end of the chamber of the device. Numerical results are used to judge the effectiveness of these techniques. The investigation shows that damping can not effectively restrain the motion of OWC when the period of incident wave is long, which may cause dangerous loads on the structure. The shut chamber can effectively restrain the motion of OWC, but alternatively cause high pressure in the chamber. A Contracting opening with a Taper (CT) can exhaust a great amount of kinetic energy of OWC, and significantly decrease the loads. It is a promising protective technique.

关键词： wave powr device protective technique wave load

Transitional function of DG to CA3 in the hippocampus

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Progress in Natural Science:Materials International 2007年第12期17卷 1436-1444页

作者： Yan Chuankui1 and Liu Shenquan2.1. Department of Mathematics, Hangzhou Normal University, Hangzhou 310036, china 2. Department of Applied Mathematics, School of Mathematical sciences, South china University of Technology, guangzhou 510640, china) Department of Mathematics Hangzhou Normal University Hangzhou 310036 China Department of Applied Mathematics School of Mathematical Sciences South China University of Technology Guangzhou 510640 China

Using single cell channel model, the transmission features of CA3-DG network in the hippocampus are investigated. The influence of the stimulation on discharge pattern of pyramidal neurons is analyzed, which shows that it starts with period spiking discharges, followed by period-doubling bifurcation to chaos, and period 3 discharge evolving into chaos, and ultimately a period of bursting discharges. By the synaptic model, the CA3-DG network model is constructed, which analyzes the summation of postsynaptic currents in the network, the influence of postsynaptic current on discharge rhythm as well as the mechanism of bursting discharges. The strong capacity of spatiotemporal encoding in the network indicates the features of CA3 network during the information transmission process in the hippocampus. The modeling result with time delay of the synaptic transmission is in accordance with the experimental phenomena of action potential in the hippocampus.

关键词： hippocampus CA3-DG period-doubling bifurcation chaos.

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,chinese academy of sciences,{2. 510301,china) 2.Tropical Marine Biological Research Station in Hainan,chinese 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) *Correspondence: Hui HUANG *Correspondence: E-mail: huanghui@*** Tel./Fax: 86-2.-844602.4.

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.

Experiment of the ^(40)Ar/^(39)Ar dating of diagenetic illite in gas reservoirs

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chinese Science Bulletin 2004年第S1期49卷 89-93页

作者： WANG Longzhang, DAI Tongmo & PENG Ping’an State Key Laboratory of Organic geochemistry, guangzhou Institute of geochemistry, CAS, guangzhou 510640, china Faculty of Resources, chinese University of Geosciences, Wuhan 430074, china 1. State Key Laboratory of Organic geochemistry Guangzhou Institute of Geochemistry CAS 510640 Guangzhou China 2. Faculty of Resources Chinese University of Geosciences 430074 Wuhan China

40Ar/39Ar dating of diagenetic illite has been performed to investigate gas reservoirs in the Sulige Gas Field of the northern Ordos Basin. A series of technical challenges were confronted, including illite purification, Ar recoil loss, and separation of diagenetic illite from detrital illite. Mineral growth ages for diagenetic illite were obtained by this experiment, from which the age of gas emplacement was deduced to be later than 169 Ma.

关键词： 40Ar/39Ar dating diagenetic illite purification of clay minerals Ar recoil loss time of gas emplacement.

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, chinese academy of sciences, 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

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 geochemistry, {2., guangzhou, Guangdong guangzhou Institute of geochemistry 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