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Field measurement and analysis of turbulence coherence for Typhoon Nuri at Macao Friendship Bridge

Science China(Technological sciences) 2010年第10期53卷 2647-2657页

作者： SONG LiLi1, PANG JiaBin2, JIANG ChengLin3. HUANG HaoHui3.& QIN Peng3.1 guangzhou {4. of Tropical and Marine Meteorology, CMA, guangzhou 510080, China 2 Tongji University, Shanghai 200092, China 3.Guangdong Climate Centre, guangzhou 510080, China 1. guangzhou institute of Tropical and Marine Meteorology CMA Guangzhou 510080 China2. Tongji University Shanghai 200092 China3. Guangdong Climate Centre Guangzhou 510080 China

For the purpose of investigating the turbulent and spatial coherent characteristics of strong wind during typhoon landing period,two 3.dimensional ultrasonic anemometer stations were set up 3. m horizontally apart on the Macao Friendship Bridge to caputure the turbulent wind velocities of Typhoon Nuri. Based on the reliable and representative field measured data,the mean wind speed and direction,turbulence intensity,turbulence integral scale,turbulence power spectra,spatial correlation coefficient and coherence function were statistically evaluated. The field measurement analysis have presented the following results: 1) Two anemometer stations provided consistent results. The mean wind speed variation in time domain presented typical M-shape curves. The strong wind (10-minute mean wind speed higher than 8th grade in Beaufort wind scale) direction changed in a big range up to 122-degrees-angle,indicating the field measurements scoped over the typhoon landing period. 2) The ratio of the longitudinal,lateral and vertical turbulence intensities of the strong wind in the typhoon eye wall region was 1:0.96:0.3.. Compared with the code defined ratio 1:0.88:0.5,the lateral component was larger and the vertical component was smaller. 3. The value of integral scale increased when the eye wall of Typhoon Nuri passed over the field measurement site. Before the center of Typhoon Nuri arrived,the integral scale of the strong typhoon wind was about twice compared with that for the non-typhoon wind. 4. The spatial correlation of the turbulent wind,coherence function curve and the decay factor had significant differences at different times during the typhoon process. In the eye wall of the typhoon,the horizontal spatial correlation was relatively strong and horizontally spatial correlation spectrum decayed slower with frequency increase. The minimum regressed coefficient C in coherence function model was 4.67,which is lower than the code defined low limit. The maximum decay factor w

关键词： typhoon field measurement and analysis turbulence characteristics coherence spectral function

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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 & Chinese academy of {3., guangzhou 5114.8, 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 Zr4.Ti14.u12.5Ni10Be22.5 (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 Be2Zr, Zr2Cu 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

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Secure multi-party computation protocol for sequencing problem

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Science China(Information sciences) 2011年第8期54卷 1654-1662页

作者： TANG ChunMing 1,2,SHI GuiHua 1 & YAO ZhengAn 3.1 School of Mathematics and Information Science,guangzhou University,guangzhou 510006, China 2State Key Laboratory of Information Security, institute of Software Science,Chinese {3. of {4.,Beijing 100080,China 3.School of Mathematics and Computational Science,Sun Yat-Sen University,guangzhou 510275,China 1. School of Mathematics and Information Science Guangzhou University Guangzhou 510006 China2. State Key Laboratory of Information Security Institute of Software Science Chinese Academy of Sciences Beijing 100080 China3. School of Mathematics and Computational Science Sun Yat-Sen University Guangzhou 510275 China

In the field of multi-party computation,an important problem is how to construct an efficient and secure multi-party computation protocol for certain specific *** the present study,we make use of a secret sharing scheme to construct an efficient and secure multi-party computation protocol for sequencing *** protocols are perfectly secure against both a passive adversary that can corrupt at most t (n-1)/2 participants, and an active adversary that can corrupt at most t 3.*** simplest sequencing problem is the Millionaires' problem.

关键词： secure multi-party computation sequencing problem secret sharing

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THE EVOLUTIONARY HISTORY OF THE WEST KUNLUN MOUNTAINS: A TECTONIC RECONSTRUCTION BASED ON STUDIES OF MAGMATISM

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地学前缘 2000年第S1期7卷 262-263页

作者： Yuan Chao 1,2 , Sun Min 2, Li Jiliang 3.WT5,5”BX](1 guangzhou institute of geochemistry, Chinese {3. of {4., guangzhou 51064.,China 2.Department of Earth {4., The University of Hong Kong, Pokfulam Road, Hong Kong, China 3.Institut

The Kunlun Mountains is situated in the north margin of the Tibetan plateau and is one of crucial areas for unraveling the tectonic evolutionary history of the plateau and Eurasia. However, there is no widely accepted model for this area. One of the reasons is that some basic issues for the tectonic reconstruction have not been well settled, they are: (1) Is the Kunlun Mountains an ancient accretion prism, or a mini continent with old basement?(2) What is the age of the Kudi ophiolite, early Paleozoic or late Paleozoic?(3. When did the South Kunlun Block accrete to the Tarim Block?(4. Do the fifth and the forth sutures represent different oceans, or they are just the chronologically different relics of the same ocean?(5) Did the Kunlun Mountains experience continuous subduction since Neoproterozoic?(6) When did the Paleo\|Tethys closed in the West Kunlun range?

关键词： West Kunlun Mountains Proto\|Tethys Paleo\|Tethys boninite series rocks accretion prism magmatic gap tectonic reconstruction

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Petrology and mineral chemistry of new ureilites found in Grove Mountains, Antarctica

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Progress in Natural Science:Materials International 2008年第4期18卷 431-439页

作者： Bingkui Miaoa,b,, Yangting Linb, Guiqin Wangc, Daode Wangc, Ziyuan Ouyangd a Key Laboratory of Geological Engineering Center of Guangxi Province, Guilin University of Technology, Guilin 54.004. China b State Key Laboratory of Lithospheric Evolution, institute of Geology and Geophysics, Chinese academy of sciences, Beijing 100029, China c Key Laboratory of Isotope Geochronology and {3.,{4. institute of {3., Chinese academy of sciences, guangzhou 51064., Chinad National Astronomical Observatories, Chinese academy of sciences, Beijing 100012, China Key Laboratory of Geological Engineering Center of Guangxi Province Guilin University of Technology Guilin 541004 China State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Key Laboratory of Isotope Geochronology and geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

Petrography and mineral chemistry of two new ureilites, GRV 021512 and 02293., from the Grove Mountains, Antarctica, are reported in this paper. GRV 021512 exhibits a typical ureilite texture, and consists of 4..3. olivine, 9.4. pigeonite and 3..1% carbo- naceous interstitial material and/or reduction product. GRV 02293. has a cataclastic porphyritic texture, and consists of 19.1% olivine and 14.1% pigeonite embedded in 66.3. carbonaceous interstitial material and/or reduction product. The coarse-grained olivine and pigeonite in both meteorites have homogeneous cores, and they are FeO-rich within the range of the ferroan subgroup (subgroup I) of olivine-pigeonite ureilites. All olivine grains of the meteorites show reduction zones along boundaries and cracks. Abundant diamond coexists with graphite as graphite-rich patches and veins in the carbonaceous interstitial material. Petrogenesis of both meteorites and the origin of diamond are discussed.

关键词： Meteorite Achondrite Ureilite Diamond Antarctica

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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 {3., 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 274.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 0.3. T, the induction time of NGH has been reduced to 4. 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, 0.22 T, 0.4.T. Especially with magnetic field intensity of 0.11 T, the induction time had even been prolonged to 4.0}min (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

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Population information extraction in Chaohu watershed based on RS and GIS

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Chinese Science Bulletin 2003年第2期48卷 181-183页

作者： LIU Jianjun1,2 & LI Chunlai3.1. institute of geochemistry, Chinese academy of {3., Guiyang 550002, China 2. Graduate School, Chinese academy of {3., Beijing 10003., China 3. National Astronomical Observatories, Chinese academy of {3., Beijing 100012, China Correspondence should be addressed to Liu Jianjun (e-mail: dhsliujj@ ***) institute of geochemistry Chinese Academy of Sciences Guiyang China Graduate School Chinese Academy of Sciences Beijing China National Astronomical Observatories Chinese Academy of Sciences Beijing China

It is always difficult to extract population in-formation of small watershed during the region environment assessment. The report adopted compound areal interpola-tion to study the population in Chaohu watershed with the GIS technique and landuse interpretation data from remote sensing. The result indicated that the method is effective to extract population information of small watershed.

关键词：巢湖流域人口分布信息提取 RS GIS 小流域生态环境评价

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Hydrogen isotopic compositions, distributions and source signals of individual n-alkanes for some typical crude oils in Lunnan Oilfield, Tarim Basin, NW China

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Science China Earth sciences 2005年第8期48卷 1220-1226页

作者： LU Hong1, LI Chao1, SUN Yongge1, PENG Ping’an1 & XIAO Zhongyao2 1. State Key Laboratory of Organic geochemistry, guangzhou institute of geochemistry, Chinese{4. of sciences, guangzhou51064., China 2. Tarim Research institute of Exploration and Development of Petroleum, China Petroleum, Korla 84.000, China 1. State Key Laboratory of Organic geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences 510640 Guangzhou China 2. Tarim Research institute of Exploration and Development of Petroleum China Petroleum 841000 Korla China

Isotopic compositions of carbon-bound hydrogen in individual n-alkanes from sev-eral typical crude oil samples from Lunnan Oilfield, Tarim Basin, NW China, were firstly measured using newly developed gas chromatography-thermal conversion-isotope ratio mass spectrometry. The similar range of δ D of individual n-alkanes of crude oils among reservoirs of different geo-logical times reflects that hydrocarbons are all derived from the same marine depositional envi-ronment. Compared to the theoretic value (?150‰) and the reported δ D values (nC13.nC27, ?160‰―?90‰) of individual n-alkanes for Ordovician-sourced crude oils in the Canadian Wil-liston Basin, the hydrogen isotopic composition of individual n-alkanes in crude oils from Lunnan Oilfield is characterized by heavy hydrogen isotopic values (nC12―nC27, ?120‰―?60‰). In terms of the factors that control the fractionation of hydrogen isotopes, relatively saline deposi-tional environment and higher thermal maturation were attributed to the heavy δ D values of in-dividual n-alkanes in crude oils from Lunnan Oilfield.

关键词： hydrogen isotopes, individual n-alkanes, distribution, hydrocarbon source, Lunnan Oilfield.

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Polyphyly of the fern family Tectariaceae sensu Ching:Insights from cpDNA sequence data

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Science China(Life sciences) 2007年第6期50卷 789-798页

作者： LIU HongMei1,2, ZHANG XianChun1, CHEN ZhiDuan1, DONG ShiYong3.& QIU YinLong4.1 State Key Laboratory of Systematic and Evolutionary Botany, institute of Botany, Chinese academy of sciences, Beijing 100093. China 2 Graduate University of Chinese academy of sciences, Beijing 10003., China 3.South China Botanical Garden, Chinese academy of sciences, guangzhou 510650, China 4.Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 4.109-104., USA State Key Laboratory of Systematic Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China Graduate University of Chinese academy of sciences Beijing 100039 China South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China Department of Ecology Evolutionary Biology University of Michigan Ann Arbor MI 48109-1048 USA

Tectariaceae are a pantropical fern family of about 20 genera, among which 8 are distributed in China. The morphological distinctiveness of the family is widely recognized, yet relatively little systematic research has been conducted on members of Tectariaceae. Phylogenetic analyses of chloroplast DNA sequence data (rbcL; atpB) from 15 species representing all 8 genera in China were carried out under parsimony criteria; Bayesian inference. The phylogenetic reconstructions indicated that the fern family Tectariaceae as traditionally circumscribed are polyphyletic. Ctenitis, Dryopsis, Lastreopsis clustered with; should be included within the newly-defined Dryopteridaceae,; Pleocnemia is also tentatively assigned to it. A narrowly monophyletic Tectariaceae is identified, which includes Ctenitopsis, Hemigramma, Pteridrys, Quercifilix,; Tectaria. In the single rbcL analysis, Arthropteris clustered with the above-mentioned monophyletic Tectariaceae. Although further investigations are still needed to identify infrafamilial relationships within the monophyletic Tectariaceae; to redefine several problematic genera, we propose a working concept here that better reflects the inferred evolutionary history of this group.

关键词： Tectariaceae, polyphyly, rbcL, atpB

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Gas hydrate fast nucleation from melting ice and quiescent growth along vertical heat transfer tube

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Science China Chemistry 2005年第1期48卷 75-82页

作者： XIE Yingming1,2, GUO Kaihua2, LIANG Deqing2, FAN Shuanshi2, GU Jianming1 & CHEN Jinggui2 1. institute of Refrigeration and Cryogenics, Shanghai Jiaotong University, Shanghai 20003., China 2. guangzhou institute of Energy Conversion, The Chinese {3. of {4., guangzhou 51064., China 1. institute of Refrigeration and Cryogenics Shanghai Jiaotong University 200030 Shanghai China 2. guangzhou institute of Energy Conversion The Chinese Academy of Sciences 510640 Guangzhou China

During the observation of HCFC14.b gas hydrate growth processes outside a ver- tical heat transfer tube, two exciting phenomena were found: fast nucleation of gas hydrate from melting ice, and the spontaneous permeation of water into the guest phases along the surface of heat transfer tube to form gas hydrate continuously. These two phenomena were explained with Zhou & Sloan’s hypothesis and the theory of surface free energy respectively, and a novel method of gas hydrate formation was presented——gas hydrate fast nucleation from melting ice and quiescent growth along heat transfer tube. There is no mechanic stirring in this method, the formed gas hydrates are compact, the ratio of unreacted interstitial water is little, which overcome the drawback of high energy cost and high ratio of unreacted interstitial water among the formed gas hydrates in the system with mechanic stirring. This finding will benefit the gas hydrate ap- plication technologies such as natural gas storage technology or cool storage technology with gas hydrate.

关键词： gas hydrate, natural gas storage, cool storage, fast nucleation from melting ice, permeation, surface free energy.

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