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Cycladophora davisiana(Radiolarian)in the Bering Sea during the late Quaternary:A stratigraphic tool and proxy of the glacial Subarctic Pacific Intermediate Water

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Science china Earth Sciences 2005年第10期48卷 1698-1707页

作者： WANG Rujian1 & CHEN Ronghua2 1. state key laboratory of Marine geology, Tongji University, Shanghai 200092, china 2. The key laboratory of Submarine Geoscience, state Oceanic administration, Hangzhou 310012, china state key laboratory of Marine geology Tongji University Shanghai china The key laboratory of Submarine Geoscience state Oceanic administration Hangzhou china

Cycladophora davisiana (Radiolarian) contents are counted in two cores of the Ber-ing Sea and correlated well with the oxygen isotopic records of ice in the deep core obtained by the Greenland Ice Sheet Project II (GISP 2) and deep-sea sediments (SPECMAP) of the world oceans. Millennial scale climatic events, for example, Younge Dryas and B?lling/Aller?d events, Heinrich1 and Dansgaard-Oeschger1events, recorded by C. davisiana percents are distin-guished from Core B4-2. C. davisiana events b, c1, c2, d, e1 and e2, respectively, corresponding to oxygen isotopic 2.0, 3.1, 3.3, 4.0, 5.1 and 5.3, are identified from Core B2-9. High resolution re-cords of C. davisian are tuned to the oxygen isotopic records in GISP 2 and SPECMAP and the depth-age frameworks are established in the two cores, supplying a stratigraphic base for future paleoceanographic and paleoclimatic studies. High C. davisiana during the glacial periods in the two cores indicate that they can serve as a proxy of the glacial Subarctic Pacific Intermediate Water, which verifies the glacial Subarctic Pacific Intermediate Water brought from the Bering Sea.

关键词： Cycladophora davisiana, stratigraphic tool, YD and B/A events, Heinrich 1 and D/O1 events, proxy of glacial Subarctic Pacific Intermediate Water, late Quaternary, Bering Sea.

Threshold quantum secret sharing between multi-party and multi-party

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Science china(Physics,Mechanics & Astronomy) 2008年第9期51卷 1308-1315页

作者： YANG YuGuang1,2,3 & WEN QiaoYan4 1 College of Computer Science and Technology,beijing University of Technology,beijing 100124,china 2 state key laboratory of Integrated Services Network,Xidian University,Xi’an 710071,china 3 state key laboratory of Information Security (Graduate University of Chinese Academy of Sciences),beijing 100049,china 4 state key laboratory of Networking and Switching Technology,beijing University of Posts and Tele-communications,beijing 100876,china College of Computer Science and Technology Beijing University of Technology Beijing 100124 China state key laboratory of Integrated Services Network Xidian University Xi’an 710071 China state key laboratory of Information Security (Graduate University of Chinese Academy of Sciences) Beijing 100049 China state key laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China

A threshold quantum secret sharing (TQSS) scheme between multi-party and multi-party was proposed using a sequence of single photons,which is useful and efficient when the parties of communication are not all present. We described the process of this TQSS scheme and discussed its security. It was shown that entan-glement is not necessary for quantum secret sharing. Moreover,the theoretic effi-ciency was improved to approach 100% as almost all the instances can be used for generating the private key,and each photon can carry one bit of information. This protocol is feasible with the present-day technique.

关键词： threshold quantum secret sharing quantum cryptography single photon multi-party and multi-party

Threshold proxy quantum signature scheme with threshold shared verification

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Science china(Physics,Mechanics & Astronomy) 2008年第8期51卷 1079-1088页

作者： YANG YuGuang1,3,4 & WEN QiaoYan2 1 College of Computer Science and Technology,beijing University of Technology,beijing 100124,china 2 state key laboratory of Networking and Switching Technology,beijing University of Posts and Tele-communications,beijing 100876,china 3 state key laboratory of Integrated Services Network,Xidian University,Xi’an 710071,china 4 state key laboratory of Information Security(Graduate University of Chinese Academy of Sciences) ,beijing 100049,china 1. College of Computer Science and Technology Beijing University of Technology Beijing 100124 China 3. state key laboratory of Integrated Services Network Xidian University Xi’an 710071 China 4. state key laboratory of Information Security (Graduate University of Chinese Academy of Sciences) Beijing 100049 China 2. state key laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China

A threshold proxy quantum signature scheme with threshold shared verification is proposed. An original signer could authorize a group as its proxy signers. Then only t or more of n persons in the proxy group can generate the proxy signature on behalf of the original signer and any t-1 or fewer ones cannot do that. When the proxy signature needs to be verified,any t or more of n persons belonging to the verification group can verify the message and any t-1 or fewer ones cannot verify the validity of the proxy signature.

关键词： quantum signature threshold proxy quantum group signature threshold shared verification

Urban effects and summer thunderstorms in a tropical cyclone affected situation over Guangzhou city

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Science china Earth Sciences 2007年第12期50卷 1867-1876页

作者： MENG WeiGuang1,3,YAN JingHua1 & HU HaiBo2 1 institute of Tropical and Marine Meteorology,Chinese Meteorological administration(CMA),Guangzhou 510080,china 2 institute of Urban Meteorology,CMA,beijing 100089,china 3 state key laboratory of Severe Weather,Chinese Academy of Meteorological Sciences,beijing 100081,china 1. institute of Tropical and Marine Meteorology Chinese Meteorological Administration (CMA) Guangzhou 510080 China 3. state key laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China 2. institute of Urban Meteorology CMA Beijing 100089 China

With data mainly from Guangzhou mesonet Automatic Weather Stations(AWS),Guangzhou Doppler Radar and satellite TBB data,characteristics and evolution of the urban heat island(UHI) over Guang-zhou City were analyzed in a tropical cyclone affected situation for early August *** particular,two thunderstorms occurring during this period respectively at the night of 4 August and in the afternoon of 7 August were investigated to study the relationships between the development of thunderstorms and the *** showed that two thunderstorms were associated with the UHI *** induced local air convergence and initiated the thunderstorm *** cases showed a general agreement in time and space for the locations of maximum UHI,convergence,convection,and *** was found to be more favorable to developing in time periods and locations with stronger intensity of *** also showed that,due to the urban effects,both thunderstorms got strengthened when moving over Guangzhou City,with maximum radar echoes observed right over the urban area and precipitation located within the *** these features reveal that two thunderstorms were urban-induced storms.

关键词： summer thunderstorms, urban heat islands (UHI), urban effects, tropical cyclone

The Construction of Numerical Scheme forHyperbolic Equation and Exact Considerationof Numerical Diffusion and Dispersion

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Communications in Nonlinear Science and Numerical Simulation 1999年第2期4卷 156-162页

作者： Qingdong CAI(state key laboratory for Turbulence Research, Peking University, beijing 100871, china) state key laboratory for Turbulence Research Peking University Beijing 100871 China

A new technique in the formulation of numerical scheme for hyperbolicequation is developed. It is different from the classical FD and FE methods. We begin withthe algebraic equations with some undefined parameters, and get the difference equationthrough Taylor-series expansion. When the parameters in the partial difference equationare defined, the equation is what the scheme will simulate. The numerical example ofthe viscous Burgers equation shows the validity of the scheme. This method deals withthe numerical viscosity and dispersion exactly, giving a preliminary explanation to someproblems that the CFD face now.

关键词： modified equation Taylor expansion consistency truncation error

Structural control of the Gagua “Wedge” Zone east of Taiwan Island on the southern Okinawa Trough

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Science china Earth Sciences 2005年第8期48卷 1165-1174页

作者： ZHENG Yanpeng1,2,3, LIU Baohua2,3, WU Jinlong2, LIANG Ruicai2,3, LIU Chenguang2,3 & ZHANG Zhengmin1 1. Marine geology College, Ocean University of china, Qingdao 266003, china 2. First institute of Oceanography, state Oceanic administration, Qingdao 266061, china 3. key laboratory of Marine Sedimentology and Environmental geology, state Oceanic administration, Qingdao 266061, china 1. Marine geology College Ocean University of China 266003 Qingdao China 2. First institute of Oceanography State Oceanic Administration 266061 Qingdao China 3. key laboratory of Marine Sedimentology and Environmental geology State Oceanic Administration 266061 Qingdao China

Based on compositive analysis and interpretation of the observed and historical data, the geophysical field characters and structural properties of the Gagua “Wedge” Zone of the sea area east of Taiwan Island and the primary tectonic stress direction and its variabilities of backarc spreading in the southern Okinawa Trough are studied. It is concluded from the study results that the Gagua “Wedge” Zone is structurally consistent with the Gagua ridge and two fault basins on both sides of the Gagua ridge, and adjusts the moving direction and distance of the western Philippine Sea plate to make the northwestward motion of the plate on its east side change to the northward subduction of the plate on its west side so that the primary tectonic stress direction of the Okinawa Trough changed from NW-SE to nearly N-S, which provided the stress source for the Okinawa Trough to enter the second spreading stage.

关键词： east of Taiwan Island, Gagua "Wedge" Zone, Okinawa Trough, structural control.

Numerical experiments for the conductive properties of saturated rock

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Science china Earth Sciences 2008年第S2期51卷 174-180页

作者： YUE WenZheng & TAO Guo state key laboratory of Petroleum Resource and Prospecting,china University of Petroleum,beijing 102249,china china Univ Petr State Key Lab Petr Resource & Prospecting Beijing 102249 Peoples R China

The reservoir evaluation as a key technology in oil exploration and production is based on the electrical transport property (ETP) of saturated rock that is described in a mathematical form with Arhcie’s equa-tion. But there have been increasing cases observed in many researches indicating that the ETP is non-Archie especially for the complex reservoir with low porosity and permeability. In this paper,the numerical experiments based on the Lattice Boltzmann method (LBM) have been employed to study the effect of porous structure and fluids on the ETP for revealing the nature of non-Archie phenomenon in micro-scale. The results of numerical experiments have proved that the saturation exponent n is a function of water saturation and porosity instead of being a constant in Archie’s equation. And then,a new formula has been developed for the EPT through combining the result of numerical simulation with that of laboratory measurements. The calculations from the new formula show very good agreement with laboratory measurements to demonstrate the efficiency of the new formula over the conventional methods in non-Archie rock.

关键词： electrical transport property non-Archie phenomenon fluid saturation porous media Lattice Boltzmann method

SILICA-SUPPORTED NICKEL AND ZIRCONIUM CATALYSTS FOR BRANCHED POLYETHYLENE

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Chinese Journal of Polymer Science 2003年第4期21卷 453-458页

作者：孙文华 state key laboratory of Engineering Plastics The Center for Molecular Sciences institute of Chemistry Chinese Academy of Sciences beijing 100080 china Chinese Acad Sci Inst Chem Ctr Mol Sci State Key Lab Engn Plast Beijing 100080 Peoples R China

8-Aminoquinoline nickel dichloride and bis(cyclopentadienyl)zirconium dichloride (Cp_2ZrCl_2) were supportedsimultaneously on silica to produce branched polyethylene successfully by combined polymerization. The supportedpolymerization results showed that the molecular weight of polyethylene increased while the molecular weight distributionbecame wider and the molecular chains of oligomers remaning in the final solution became shorter as compared to theoligomers obtained in polymerization processes with pure 8-aminoquinoline nickel dichloride catalysis, as well as theCp_2ZrCl_2 and nickel combination system. With decreasing amount of Ni catalyst in the supported catalyst, the molecular chains of oligomers in the resulting solution became shorter, while α-olefin selectivity increased.

关键词： 8-Aminoquinoline nickel dichloride, Cp_2ZrCl_2 Silica supported catalysts Branched polyethylene

The role of the catalysts with highly dispersed and isolated active sites in the selective oxidation of light hydrocarbons

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Progress in Natural Science:Materials International 2005年第12期15卷 1066-1072页

作者： WANG Hongxuan and ZHAO Zhen state key laboratory of Heavy Oil Processing,china University of Petroleum,beijing 102249,china state key laboratory of Heavy Oil Processing China University of Petroleum Beijing 102249 China

This review summarizes the role of catalysts with highly dispersed and isolated active sites (active sites:supported atoms f≤0.5 %) in the selective oxidation of light hydrocarbons,such as methane,ethane and propane,into oxygenates and the epoxidation of *** plausible structures of the highly dispersed and isolated active species,as well as their effects on the catalytic performances are *** special physico-chemical properties and the functional mechanism of the catalysts with highly dispersed and isolated active sites,as well as the preparation,characterization of the catalysts with highly dispersed and isolated active sites and their applications in other types of reactions of lower hydrocarbons are summarized.

关键词： selective oxidation light hydrocarbons highly dispersed isolated active sites oxygenates catalyst methane ethane propane