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Multiparty simultaneous quantum identity authentication with secret sharing

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Science china(Physics,Mechanics & Astronomy) 2008年第3期51卷 321-327页

作者： YANG YuGuang1,2,WEN QiaoYan3 & ZHANG Xing4,5 1 College of Computer Science and Technology,beijing university of Technology,beijing 100022,china 2 State Key Laboratory of Information Security (Graduate university of the Chinese Academy of sciences),beijing 100049,china 3 School of Science,beijing university of Posts and Telecommunications,beijing 100876,china 4 Institute of Electronic Technology,Information Engineering university,zhengzhou 450004,china 5 Trusted Computing Laboratory,beijing university of Technology,beijing 100022,china College of Computer Science and Technology Beijing University of Technology Beijing China State Key Laboratory of Information Security (Graduate university of the Chinese Academy of sciences) Beijing China School of Science Beijing University of Posts and Telecommunications Beijing China Institute of Electronic Technology Information Engineering University Zhengzhou China Trusted Computing Laboratory Beijing University of Technology Beijing China

Two multiparty simultaneous quantum identity authentication (MSQIA) protocols based on secret sharing are presented. All the users can be authenticated by a trusted third party (TTP) simultaneously. In the first protocol,the TTP shares a random key K with all the users using quantum secret sharing. The ith share acts as the authentication key of the ith user. When it is necessary to perform MSQIA,the TTP generates a random number R secretly and sends a sequence of single photons encoded with K and R to all the users. According to his share,each user performs the corresponding unitary operations on the single photon sequence sequentially. At last,the TTP can judge whether the impersonator exists. The sec-ond protocol is a modified version with a circular structure. The two protocols can be efficiently used for MSQIA in a network. They are feasible with current technol-ogy.

关键词： quantum identity authentication secret sharing quantum cryptography

Study on attribute characterization for reservoir dynamic monitoring by seismic

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Science china Earth sciences 2008年第S2期51卷 218-225页

作者： CHEN XiaoHong1,3,LI JingYe2,3 & ZHAO Wei4 1 Key Lab of Geophysical Exploration of CNPC,china Petroleum university,beijing 102249,china 2 Basin & Reservoir research center,china Petroleum university,beijing 102249,china 3 State Key Laboratory of Petroleum Resource and Prospecting,china university of Petroleum,beijing 102249,china 4 research center of CNOOC,beijing 100027,china Key Lab of Geophysical Exploration of CNPC China Petroleum University Beijing China State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing China Basin & Reservoir research center China Petroleum University Beijing China research center of CNOOC Beijing China

Study on characterizing reservoir parameters dynamic variations by time-lapse seismic attributes is the theoretical basis for effectively distinguishing reservoir parameters variations and conducting time-lapse seismic interpretation,and it is also a key step for time-lapse seismic application in real oil fields. Based on the rock physical model of unconsolidated sandstone,the different effects of oil saturation and effective pressure variations on seismic P-wave and S-wave velocities are calculated and analyzed. Using numerical simulation on decoupled wave equations,the responses of seismic amplitude with different offsets to reservoir oil saturation variations are analyzed,pre-stack time-lapse seismic attributes differences for oil saturation and effective pressure variations of P-P wave and P-S converted wave are calculated,and time-lapse seismic AVO (Amplitude Versus Offset) response rules of P-P wave and P-S converted wave to effective pressure and oil saturation variations are compared. The theoretical modeling study shows that it is feasible to distinguish different reservoir parameters dynamic variations by pre-stack time-lapse seismic information,including pre-stack time-lapse seismic attributes and AVO information,which has great potential in improving time-lapse seismic interpreta-tion precision. It also shows that the time-lapse seismic response mechanism study on objective oil fields is especially important in establishing effective time-lapse seismic data process and interpreta-tion scheme.

关键词： time-lapse seismic dynamic monitoring rock physical model pre-stack attribute Amplitude Versus Offset (AVO)

Study on blister of the coating on solid cantilevers of hydraulic supports for coal mining

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Science china(Technological sciences) 2010年第12期53卷 3183-3188页

作者： MENG GuoZhe1, FU JinLiang2, SUN FeiLong1, SHAO YaWei1, ZHANG Tao1 & WANG FuHui1, 3 1 Corrosion and Protection Laboratory, Key Laboratory of Superlight Materials and Surface Technology (Harbin Engineering university), Ministry of Education, Harbin 150001, china 2 Technology center of zhengzhou Coal Mining Machinery Group Co. Ltd., zhengzhou 100049, china 3 State Key Laboratory for Corrosion and Protection, Institute of Metal research, Chinese Academy of sciences, Shenyang 110016, china Corrosion and Protection Laboratory Key Laboratory of Superlight Materials and Surface Technology (Harbin Engineering University) Ministry of Education Harbin China Technology center of zhengzhou Coal Mining Machinery Group Co. Ltd. Zhengzhou China State Key Laboratory for Corrosion and Protection Institute of Metal Research Chinese Academy of Sciences Shenyang China

In this work, blister of the Cu-Sn plus Cr coating on solid cantilevers of hydraulic supports for coal mining was investigated by hydrogen-charging, Devanathan-Stachurski method and electrochemical impedance spectroscopy (EIS) measurement. It was found that the permeation hydrogen during the pickling process and the electroplating process was responsible for the blisters. The residual tensile stress due to the machining process would increase the permeation hydrogen amount during pickling and electroplating processes.

关键词： hydrogen blister hydrogen permeation EIS sub-surface hydrogen concentration

A Genome-wide Functional Characterization of Arabidopsis Regulatory Calcium Sensors in Pollen Tubes

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Journal of Integrative Plant Biology 2009年第8期51卷 751-761页

作者： Liming Zhou1,2, Ying Fu1,2 and Zhenbiao Yang2,3 (1State Key Laboratory of Plant Physiology and Biochemistry, Department of Plant sciences, College of Biological sciences, china Agricultural university, beijing 100193, china 2china Agricultural university (CAU)-university of California, Riverside (UCR) Joint center for Biological sciences and Biotechnology, College of Biological sciences, china Agricultural university, beijing 100193, china 3center for Plant Cell Biology and Department of Botany and Plant sciences, university of California, Riverside, CA 92521, USA) State Key Laboratory of Plant Physiology and Biochemistry Department of Plant Sciences College of Biological Sciences China Agricultural University Beijing 100193 China china Agricultural university (CAU)-university of California Riverside (UCR) Joint Center for Biological Sciences and Biotechnology College of Biological Sciences China Agricultural University Beijing 100193 China center for Plant Cell Biology and Department of Botany and Plant sciences University of California Riverside CA 92521 USA)

Calcium, an ubiquitous second messenger, plays an essential and versatile role in cellular signaling. The diverse function of calcium signals is achieved by an excess of calcium sensors. Plants possess large numbers of calcium sensors, most of which have not been functionally characterized. To identify physiologically relevant calcium sensors in a specific cell type, we conducted a genome-wide functional survey in pollen tubes, for which spatiotemporal calcium signals are well-characterized and required for polarized tip growth. *** members of calrnodulin （CAM）, CaM-like （CML）, calcium-dependent protein kinase （CDPK） and calcineurin B-like protein （CBL） families were tagged with green fluorescence protein （GFP） and their localization patterns and overexpression phenotypes were characterized in tobacco pollen tubes. We found that several fusion proteins showed distinct overexpression phenotypes and subcellular localization patterns. CDPK24-GFP was localized to the vegetative nucleus and the generative cell/sperms. CDPK32-GFP caused severe growth depolarization. CBL2-GFP and CBL3-GFP exhibited dynamic patterns of subcellular localization, including several endomembrane compartments, the apical plasma membrane （PM）, and cytoskeleton-like structures in pollen tubes. Their overexpression also inhibited pollen tube elongation and induced growth depolarization. These putative calcium sensors are excellent candidates for the calcium sensors responsible for the regulation of calcium homeostasis and calciumdependent tip growth and growth oscillation in pollen tubes.

关键词： Arabidopsis calcium sensor calcium signaling Rho-related GTPase from plants subcellular localization tip growth

β2 Adrenergic receptor on T lymphocytes and its clinical implications

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Progress in Natural Science:Materials International 2009年第1期19卷 17-23页

作者： Xuelai Fan a,Yuedan Wang b,a Peking university,School of Pharmaceutical sciences,beijing 100083,china b Peking university,School of Basic Medical sciences,beijing 100083,china Peking university School of Pharmaceutical Sciences Beijing 100083 China Peking university School of Basic Medical Sciences Beijing 100083 China

Sustained complex cross-talk between the immune system and the nervous system plays a vital role in retaining homeostasis in a healthy *** of the central regulatory mechanisms involved is the existence and functions of β2-adrenergic receptors(β2AR) on T *** article reviews research progress made recently,including the expression of adrenergic receptors on T lymphocytes,the structure and intracellular pathways of β2AR,the activation of β2AR by either endogenous or exogenous agonists,and the effect of β2AR stimulation on T cells which alters T cell proliferation,differentiation,cytokine production and T-helper-mediated antibody ***,we discuss the roles of β2AR played in the pathogenesis and treatment of autoimmune diseases.

关键词： Neuroimmunology β2-adrenergic receptor T cell Autoimmune

Critical load of sulfur deposition for ecosystemand its application in china

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Journal of environmental sciences 1995年第3期7卷 325-337页

作者： Zhao Dianwu Zhang Xiaoshan Yang Jianxin(research center for eco-Environrnental sciences , Chinese Academy of Sceiences, beijing 100085, china)Mao Jietai(Department of Geophysics, Peking university. beijing 100871 . china)Xiong Jiling(Guizhou Institute o

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关键词： sulfur deposition critical load : ecosystem.

Patterns of platinum-group elements in mantle peridotite, granulite xenoliths and basalt in Hannuoba

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Chinese Science Bulletin 1999年第18期44卷 1676-1681页

作者： CHU Xuelei, LI Xiaolin, XU Jiuhua and LIU Jianming1. The research center of Mineral Resources Exploration , Chinese Academy of sciences , beijing 100101, china 2. Institute of Geology , Chinese Academy of sciences , beijing 100029, china 3. Institute of High Energy Physics , Chinese Academy of sciences , beijing 100817 , china 4. beijing {12. of Science and Engineering , beijing 100083, china Corresponding author The research center of Mineral Resources Exploration Chinese Academy of Sciences Beijing China Institute of Geology Chinese Academy of Sciences Beijing China Institute of High Energy Physics Chinese Academy of Sciences Beijing China beijing university of Science and Engineering Beijing China

Neutron activation analysis after preconcentration of nickel sulfide fire assay was used in measurement of Ru, Ph, Pd, Os, Ir, Pt (i.e. PGE elements) and Au concentrations for basalt, mantle and granulite xenoliths in Hannuoba. The chondrite- and primitive mantle-normalized PGE patterns generally exhibit flat (for Iherzolite), negative slope (for harzburgite),

关键词： mantle xenolith granulite xenolith basalt platinum-group element Hannuoba.

Sea-salt aerosol transport patterns over the Northern Hemisphere inferred from two subarctic ice core records

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Science china Earth sciences 2005年第4期48卷 576-584页

作者： YAN Yuping1,2, KANG Shichang2,3,5, SUN Junying4,5, Paul A. Mayewski2 & QIN Dahe5 1. National Climate center, china Meteorological Administration, beijing 100081, china 2. Climate Change Institute, university of Maine, Orono, ME 04469, USA 3. Institute of Tibetan Plateau research, Chinese Academy of sciences, beijing 100085, china 4. Chinese Academy of Meteorological sciences, beijing 100081, china 5. Key Laboratory of Ice Core and Cold Regions Environment, Cold and Arid {12. and Engineering research Institute, Chinese Academy of sciences, Lanzhou 730000, china National Climate center China Meteorological Administration Beijing China Climate Change Institute University of Maine Orono ME USA Institute of Tibetan Plateau research Chinese Academy of Sciences Beijing China Key Laboratory of Ice Core and Cold Regions Environment Cold and Arid Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China Chinese Academy of Meteorological sciences Beijing China

Atmospheric circulation reconstruction based on glaciochemical records requires knowledge of chemical concentration controls, such as source, transport pathway and strength. To gain insight into these processes, the relationships between glaciochemical records from two Northern Hemisphere sites (Mt. Logan in Yukon Territory and 20D in southern Greenland) and instrumental sea level pressure (SLP) series are investigated. Calibrations between Mt. Logan sea-salt sodium (ssNa+) concentration and SLP series show that ssNa+ concentrations are closely correlated with the autumntime (SON) Aleutian Low and the summertime (JJA) North Pacific Subtropical High. Both the deepened Aleutian Low and enhanced North Pacific Sub- tropical High strengthen the transport of sea-salt aerosols from the North Pacific to the Mt. Logan region. Calibrations between 20D ssNa+ concentrations and SLP series indicate that ssNa+ concentrations are closely related to the wintertime (Jan.) Icelandic Low. A deepening of the Icelandic Low strengthens winter storms and frequent cyclogenesis over the North Atlantic and pushes more sea-salt laden air masses to the Greenland ice sheet. Therefore, ice core ssNa+ records from the Mt. Logan region can be considered as a proxy for reconstructing the au- tumntime Aleutian Low and summertime North Pacific Subtropical High, and the ssNa+ records from Greenland ice core (20D) may provide a proxy for reconstructing the wintertime Icelandic Low.

关键词： sea-salt aerosol, ice core records, sea level pressure, subarctic regions.

A one-dimensional heat transfer model of the Antarctic Ice Sheet and modeling of snow temperatures at Dome A, the summit of Antarctic Plateau

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Science china Earth sciences 2010年第5期53卷 763-772页

A vertical one-dimensional numerical model for heat transferring within the near-surface snow layer of the Antarctic Ice Sheet was developed based on simplified parameterizations of associated physical processes for the atmosphere, radiation, and snow/ice systems. Using the meteorological data of an automatic weather station (AWS) at Dome A (80°22′S, 70°22′E), we applied the model to simulate the seasonal temperature variation within a depth of 20 m. Comparison of modeled results with observed snow temperatures at 4 measurement depths (0.1, 1, 3, 10 m) shows good agreement and consistent seasonal variations. The model results reveal the vertical temperature structure within the near-surface snow layer and its seasonal variance with more details than those by limited measurements. Analyses on the model outputs of the surface energy fluxes show that: 1) the surface energy balance at Dome A is characterized by the compensation between negative net radiation and the positive sensible fluxes, and 2) the sensible heat is on average transported from the atmosphere to the snow, and has an evident increase in spring. The results are considered well representative for the highest interior Antarctic Plateau.

关键词： Antarctic Ice Sheet near-surface layer energy transfer numerical model