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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.

Geochemical behavior of elements at fossil sea floor water/sediment interface

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chinese Science Bulletin 1999年第S2期44卷 232-233页

作者： ZHANG Haihua~1, XIA Yu~1, WANG Zuwei~2.and ZHOU Yongzhang~3 1. guangzhou institute of {2., chinese academy of Science, guangzhou 510640, china 2. Department of Geography, Tianjin Normal University, Tianjin 300071, china 3. Department of Earth sciences, Zhongshan University, guangzhou 5102.5, china guangzhou institute of {2. Chinese Academy of Science Guangzhou 510640 China Department of Geography Tianjin Normal University Tianjin 300071 China Department of Earth sciences Zhongshan University Guangzhou 510275 China

THIS note deals with the geochemical behavior of elements near the water/sediment interface of a fossil seafloor. The Nandan-Hechi basin, located in northwest Guangxi, Southern china, is selected for exemplified study. It is an elongated basin, and developed on a Caledonian basement. Its Devonian strata hosthydrtothermally sedimentary formations, and are typical of the intra-platformal basin facies sediments oversouthern china. A steady sedimentary sequence may be observed, commonly going from carboniferouspelite at bottom, upward through bedded chert, thickly banded argillaceous limestone, thinly bandedsiliceous limestone and small lensiod argillaceous limestone in the middle, to coarse lensoid siliceousand/or argillaceous limestone at the top. The chert and some argillaceous limestone are related to hydrothermally sedimentary origin. The present study focuses on the lensoid argillaceous limestone formation. This formation contains the following characteristic sedimentary structures: small lensoid structure,vermiform structure, wave-shaped banded structure, massive structure, white framboid structure, andcage netting structure.

关键词： water/sediment interface sedimentation periodicity sedimentary geochemistry basin.

Loss of energetic particles due to feedback control of resistive wall mode in HL-3

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Plasma Science and Technology 2024年第10期26卷 17-28页

作者： Yifei ZHAO Yueqiang LIU guangzhou HAO Zhengxiong WANG Guanqi DONG Shuo WANG Chunyu LI Guanming YANG Yutian MIAO Yongqin WANG Dalian University of Technology Dalian 116024People’s Republic of China General Atomics San Diego CA 92186-5608United States of America Southwestern institute of Physics Chengdu 610041People’s Republic of China

Effects of three-dimensional(3D)magnetic field perturbations due to feedback control of an unstable n=1(n is toroidal mode number)resistive wall mode(RWM)on the energetic particle(EP)losses are systematically investigated for the HL-3 *** MARS-F(Liu et al 2.00 *** 73681)code,facilitated by the test particle guiding center tracing module REORBIT,is utilized for the *** RWM is found to generally produce no EP loss for cocurrent particles in *** the same perturbation level at the sensor location for the close-loop system,feedback produces nearly the same loss of counter-current EPs compared to the open-loop *** however that the sensor signal is ten times smaller in the close-loop system than the open-loop counter part(reflecting the fact that the RWM is more stable with feedback),the counter-current EP loss is found significantly reduced in the *** of EP losses occur only for particles launched close to the plasma edge,while particles launched further away from the plasma boundary experience much less *** strike points of lost EPs on the HL-3 limiting surface become more scattered for particles launched closer to the plasma *** into account the full gyro-orbit of particles while approaching the limiting surface,REORBIT finds slightly enhanced loss fraction.

关键词： energetic particles resistive wall mode HL-3

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,{2.,guangzhou 510070. Professor, guangzhou institute of Energy Conversion,{2., 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

Alterations in DNA methylation and genome structure in two rice mutant lines induced by high pressure

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Science china(Life sciences) 2006年第2期49卷 97-104页

作者： SHEN Sile1,3, WANG Zhenwei3, SHAN Xiaohui2. WANG Hua3, LI Ling3, LIN Xuyun2. LONG Likun2. WENG Kenan4, LIU Bao2.& ZOU Guangtian1 1. National Laboratory of Superhard Materials, Jilin University, Changchun 130012. china 2. institute of Genetics and Cytology, Northeast Normal University, Changchun 13002., china 3. College of Life Science, Jilin University, Changchun 130012. china 4. guangzhou institute of geochemistry, chinese academy of sciences, guangzhou 510640, china 1. National Laboratory of Superhard Materials Jilin University Changchun 130012 China 3. College of Life Science Jilin University Changchun 130012 China 2. institute of Genetics and Cytology Northeast Normal University Changchun 130024 China 4. guangzhou institute of {2. Chinese Academy of Sciences Guangzhou 510640 China

By using high-pressure treatment, two mutant lines were obtained from agenetically stable japonica rice cultivar Bijing38. Genomic DNA of the mutant lines, together withthe original line (Bijing38), was either undigested or digested by Hpa ⅡIMspⅠ, and then subjectedto molecular analysis using two markers, ISSR and RAPD. Results indicated that changes in the PCRamplification profiles of both markers are apparent in the two mutant lines compared with theoriginal rice cultivar, suggesting that there had been both sequence changes and DNA methylationmodifications in the mutant lines. Southern blot analysis using diverse sequences, including twocellular genes (S2.and S3), a set of retrotransposons (Osr7, Osr36, Tos19 and more), and a MITEtransposon family (mPing and Pong), confirmed the results, and indicated that changes in DNAmethylation pattern, genomic structure, and possible activation of some transposons indeed occurredin the mutant lines. Moreover, these changes are stably maintained through selfed generations and indifferent organs. Thus, our results indicate that it is possible to obtain stable mutants in riceby high pressure treatments, and the molecular basis of the mutants may include both genetic andepigenetic changes. Therefore, high hydrostatic pressure seems a promising approach for plantmutagenesis.

关键词： DNA methylation, genomic changes, high pressure, mutagenesis, rice.

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 {2., chinese academy of sciencesWushan, guangzhou 510640 guangzhou institute of {2. 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

Zircon SHRIMP U-Pb geochronology and petrogenesis of the plagiogranites from the Lagkor Lake ophiolite,Gerze,Tibet,china

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chinese Science Bulletin 2007年第5期52卷 651-659页

作者： ZHANG YuXiu1,2. ZHANG KaiJun1,3, LI Bing1,2. WANG Yang1,2. WEI QingGuo1,2.& TANG XianChun1,2.1 Key Laboratory of Marginal Sea Geology, guangzhou institute of {2., chinese academy of sciences, guangzhou 510640, china 2.Graduate University, chinese academy of sciences, Beijing 100039, china 3 Department of Earth sciences, Nanjing University, Nanjing 2.0093, china Key Laboratory of Marginal Sea Geology Guangzhou Institute of GeochemistryChinese Academy of Sciences Guangzhou 510640 China

地关系与 petrographical 一起， petrological ，和 geochemicalcharacteristics ，和锆石人口，显示从在 Bangong-Nujiang 缝术地区的 Lagkor Lakeophiolite 的 plagiogranites (～ Gerze 县的 2. km 南方，中央西藏，中国)，由在海洋的外壳的运输期间的可锻的砍源于含水的斑粝岩的 anatexis 。因此，这种 plagiogranite 比传播海洋的外壳晚对或很少同时代。锆石虾 166 ±使 2.5 妈变老因为 plagiogranites 显示海洋的盆在中间的侏罗记在 Bangong-Nujiang 地区的西方的部分存在。

关键词：西藏改则县拉果错湖泊蛇绿岩斜长花岗岩锆SHRIMP U-Pb地质年代岩石成因

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 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