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An efficient quantum secret sharing protocol with orthogonal product states

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Science china(Physics,Mechanics & Astronomy) 2007年第3期50卷 331-338页

作者： YANG YuGuang1,2. WEN QiaoYan3.& ZHU FuChen4 1 school of Computer, beijing University of Technology, beijing 10002.,{3. 2.State Key Laboratory of Information Security, graduate University of Chinese Academy of Sciences, beijing 10002.,{3. 3.school of Science, beijing University of Posts and Telecommunications, beijing 100876,{3. 4 National Key Laboratory for Modern Communications, Chengdu 610041,{3. school of Computer Beijing University of Technology Beijing China State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing China school of Science Beijing University of Posts and Telecommunications Beijing China National Key Laboratory for Modern Communications Chengdu China

An efficient quantum secret sharing protocol with orthogonal product states in the 3.3.Hilbert space is presented. The particles in the orthogonal product states form two particle sequences. One sequence is sent to Bob and the other is sent to Charlie after rearranging the particle orders. With the help of Alice, Bob and Charlie make the corresponding local measurement to obtain the information of the or- thogonal product states prepared. This protocol has many distinct features such as great capacity and high efficiency.

关键词： quantum secret sharing orthogonal product state orthogonal measurement

Simulation of aerodynamic performance affected by vortex generators on blunt trailing-edge airfoils

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Science china(Technological Sciences) 2010年第1期53卷 1-7页

作者： YANG Ke1,2.ZHANG Lei1,3.& XU JianZhong1,2.1 Institute of Engineering Thermophysics,Chinese Academy of Sciences,beijing 100190,{3. 2.Key Laboratory of Wind Energy Utilization,Chinese Academy of Sciences,beijing 100190,{3. 3.graduate school of Chinese Academy of Sciences,beijing 100190,{3. Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing China Key Laboratory of Wind Energy Utilization Chinese Academy of Sciences Beijing China graduate school of Chinese Academy of Sciences Beijing China

An investigation was carried out by numerical simulation on a wind turbine airfoil and a blunt trailing-edge airfoil with and without vortex generators (VGs), and the performance of the airfoils was analyzed. By the simulation of airfoil DU 91-W2.2.0 it was verified that the numerical method and model were credible. Based on this airfoil, a new one with a blunt trailing edge of 6% chord was blended by symmetrically adding thickness, and its characteristics curves were obtained through computing at key angles of attack. Additionally, the pressure distribution on blended airfoil was analyzed by comparing to the airfoil without blend. The interaction of streamwise vortices induced by VGs with trailing vortex or separation vortex was considered, followed by the uncovery of how VGs can suppress the boundary layer separation.

关键词： vortex generators airfoil blunt trailing-edge

Application of the moist vorticity vector in the analysis of a heavy rainfall event in North china

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Progress in Natural Science:Materials International 2007年第12期17卷 1457-1465页

作者： Zhao Yu1,2.3. Wang Jianguo4 and Xue Deqiang2.1. Laboratory of Cloud-Precipitation Physics and Severe Storms, Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 10002., china 2. Shandong Provincial Meteorological Observatory, Jinan 2.003., china 3. {3. University of Chinese Academy of Sciences, beijing 10003., china 4. Shandong Provincial Meteorological Bureau, Jinan 2.003., china) Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Shandong Provincial Meteorological Observatory Jinan 250031 China graduate University Chinese Academy of Sciences Beijing 100039 China Shandong Provincial Meteorological Bureau Jinan 250031 China

The moist vorticity vector (MVV), defined as (ζa×▽qv)/ρ introduced by Gao et al. is used to study a heavy rainfall event in North china. The MVV has zonal, meridional and vertical components in a three-dimensional framework. Analysis of domain-mean and mass-integrated quantities shows that the variation of the vertical component of the MVV closely follows the variation of the cloud hydrometeors, with a linear correlation coefficient of 0.95, indicating that the vertical component of the MVV is strongly associated with midlatitude convection. Further analysis shows that the vertical component of the MVV reflects the interaction between the horizontal vorticity and the horizontal specific humidity gradient, which can associate dynamic and thermodynamic processes with cloud microphysical processes. Thus, this study can help to understand how the interaction between circulations and clouds aids the development of convection, and the MVV can be used to trace the development and evolution of heavy rainfall.

关键词： moist vorticity vector heavy rainfall modeling study.

Identification of human dopamine receptors agonists from Chinese herbs

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Acta Pharmacologica Sinica 2007年第1期28卷 132-139页

作者： Yi-lin ZHANG~(1,2.3.4) Hai-qing ZHANG~(1,2.3.4) Xiao-yu LIU~3.Shi-neng HUA~3.Lu-bing ZHOU~3.Jun YU~2.Xue-hai TAN~(3.5)1 {3. school of the Chinese Academy of Sciences,{2. {3.,china 2.{2. Genomics Institute,Chinese Academy of Sciences {2. 1013.0,china 3.HD Biosciences Co Ltd,Shanghai 2.12.3.china graduate school of the Chinese Academy of Sciences Beijing China beijing Genomics Institute Chinese Academy of Sciences Beijing China HD Biosciences Co Ltd Shanghai China

Aim:To find human dopamine receptors,especially Dl-like receptor specific ago-nists from Chinese herbs as potential antihypertension drug ***:TwoD l-like receptor cell lines carrying a μ-lactamase reporter gene,and a D2.receptorcell line coexpressing a promiscuous G protein G15 were constructed using HEK2.3.ells.A natural compound library made from fractionated samples of herbal ex-tracts was used for high-throughput screening（HTS）against one of the cell lines,HEK/D5R/*** interested hits were evaluated for their activities againstvarious dopamine ***:Fourteen hits were identified from primaryscreening,of which 2.of the better hit samples,HD052. and HD0059,were selectedfor further material and activity analysis,and to obtain 2.compounds that ap-peared as 2.single peaks in HPLC,HD052.H01 and ***0059H01could activate D 1,D2.and D5 receptors,with EC50values of 2.2. μg/mL,0.85 μg/mL,and 1.41 μg/mL,***052.H01 could only activate DlR and D5Rwith EC50values of 2.95 μg/mL and 8.3. μg/***:We established cell-based assays for 3.different human dopamine receptors and identified specificagonists HD052.H01 and HD0059H01 through *** specific agonist to D1-like receptors,HD052.H01,may become a new natural product-based drug leadfor antihypertension treatment.

关键词： dopamine receptors natural products high throughput screening hypertension

Land cover changes based on plant successions: Deforestation, rehabilitation and degeneration of forest in the upper Dadu River watershed

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Science china Earth Sciences 2005年第12期48卷 2214-2230页

作者： YAN Jianzhong1,2.3. ZHANG Yili1, BAI Wanqi1, LIU Yanhua4, BAO Weikai5, LIU Linshan1, 2.& ZHENG Du1 1. Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, beijing 100101,{3. {2. of the Chinese Academy of Sciences,{3.,{3. 3. College of Resources and Environment, Southwest Agricultural University, Chongqing 400716,{3. 4. The Ministry of Science and Technology, P. C.{3., beijing 100862.{3. 5. Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041,{3. Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China graduate school of the Chinese Academy of Sciences Beijing China College of Resources and Environment Southwest Agricultural University Chongqing China The Ministry of Science and Technology P. C. China Beijing China Chengdu Institute of Biology Chinese Academy of Sciences Chengdu China

To link regional land use/cover changes with environmental effects, land cover changes are required to reflect vegetation successions, whereas the land cover classification systems commonly used nowadays cannot serve this purpose. In this paper, a new land cover classification system is established in which land covers are classified by the vegetation succes-sions, taking Zamtang County, Barkam County and Jinchuan County in the upper Dadu River watershed as a study area. Using multi-temporal remote sensing images, the land cover data of 1967, 1986 and 2.00 are obtained by means of integration of unsupervised classification and visual interpretation methods. The database facilitates the study of land use/cover changes, en-vironmental effects and ecological construction. Land cover changes reflect the main ecological processes in the upper Dadu River watershed. The landscape composed mainly of grasslands, wildwoods and alpine scrubs in 1967 was changed to that of grasslands, secondary forests, al-pine scrubs, fragmentary wildwoods, artificial forests, secondary scrubs in 2.00, meanwhile, the landscape got more fragmentized. The total area of the forests decreased by 9.43.. Study results have shown the process of restoration of logged areas in forest centers. From 1967 to 2.00, only 6.86 percents of logged areas were converted to shrubs, meadows or crop-lands, and the rest were converted into artificial forests or secondary forests. So the ecological shelter functions will be restored, stage by stage. Firewood collection, charcoal production and overgrazing are the three major triggers for the extensive degradation of alpine oak forests, Sa-bina tibetica forests and meadows. The arid valley grasslands expanded too. The degradation of vegetation in the southern slopes impairs ecological shelter functions and affects livelihood of local residents, so it is essential to find effective measures for ecological restoration and recon-struction. Field investigations have found

关键词： land use/cover classification, upper Dadu River watershed, vegetation successions, GIS, RS.

Explicit analytical solutions of the anisotropic Brinkman model for the natural convection in porous media(Ⅱ)

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Science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 422-430页

作者： CAI Ruixian1, GOU Chenhua1, 2.& ZHANG Na1 1. Institute of Engineering Thermophysics, Chinese Academy of Sciences, beijing 100080, china {2., Chinese Academy of Sciences, beijing 100080, china Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing China graduate school Chinese Academy of Sciences Beijing China

Some algebraically explicit analytical solutions are derived for the anisotropic Brinkman model―an improved Darcy model―describing the natural convection in porous media. Besides their important theoretical meaning (for example, in analyzing the non-Darcy and anisotropic effects on the convection), such analytical solutions can be the benchmark solutions that can promote the development of computational heat and mass transfer. Some solutions considering the anisotropic effect of permeability have been given previously by the authors, and this paper gives solutions including the anisotropic effect of thermal conductivity and the effect of heat sources.

关键词： explicit analytical solution, porous medium, natural convection, Brinkman model, anisotropic.

Isotopic feature and uranium dating of the volcanic rocks in the Okinawa Trough

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中国科学：地球科学英文版 2006年第4期49卷 375-383页

作者： HUANG Peng1,2. LI Anchun1, HU Ningjing2.3. FU Yongtao1& MA Zhibang4 1. Institute of Oceanology, Chinese Academy of Sciences, Qingdao 2.6071,{3. 2. graduate school of the Chinese Academy of Sciences,{2.,{3. 3. Institute of Soil Science, Chinese Academy of Sciences, Nanjing 2.0008,{3. 4. Institute of Geology and Geophysics, Chinese Academy of Sciences, beijing 10002.,{3. Institute of Oceanology Chinese Academy of Sciences Qingdao China graduate school of the Chinese Academy of Sciences Beijing China Institute of Soil Science Chinese Academy of Sciences Nanjing China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

Volcanic rocks from the northern and middle Okinawa Trough were dated by ura- nium-series dating method. Differential fractions using magnetic procedure were designed to separate samples. New report on the ages and isotopic data of rocks in the northern trough (especially black pumice) was discussed. Based on the uranium dates and Sr-Nd isotopic ratio, magmatic evolution process of the Okinawa Trough was noted. Firstly, there have been wide silicic volcanic activities in the Okinawa Trough from late Pleistocene to present, and the volcanic rocks can be divided into three subgroups. Secondly, magma generally came from PREMA source area under the Okinawa Trough. Magmatic evolution in the northern trough was similar to the middle, but different to the south. Finally, volcanic activities indicated that opening of the southern Okinawa Trough did not happen due to the collision between Luson Arc and Eurasian Plate until the early Pleistocene.

关键词： Okinawa Trough, black pumice, uranium-series dating, Sr-Nd isotopic ratio, magmatic evolution.

Structures and physical properties of rigid polyurethane foams with water as the sole blowing agent

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Science china Chemistry 2006年第4期49卷 363-370页

作者： LI Xiaobin1,2. CAO Hongbin1 & ZHANG Yi1 1. Institute of Process Engineering, Chinese Academy of Sciences, beijing 100080, china {2. of the Chinese Academy of Sciences,{3., china Institute of Process Engineering Chinese Academy of Sciences Beijing China graduate school of the Chinese Academy of Sciences Beijing China

Rigid polyurethane foams blown by varying water level were prepared in this study. The structures and physical properties of rigid polyurethane foams blown by water were measured with FT-IR, universal testing machine (Instron3.65), scanning electron microscope (SEM) and differential scanning calorimeter (DSC). The results show that polyurea and polybiuret were the typical charac- teristics, and the cream time and gel time were shorter for the fully water blown rigid foams than that for the fully cyclopentane blown foams. The density of foam samples decreased from 45.0 kg/m3.to 2..4 kg/m3.with the increase of water level from 3.pph to 7 pph. Compressive strength exhibited the similar behavior with density. The average cell size of foam samples ranged from 2.1 μm to 3.6 μm with the increase of water level from 3.pph to 7 pph, respectively. At the same time, poorer dimen- sional stability was encountered with the increase of average cell size due to fast diffusion rate of CO2.out of the foam. The results of thermal analysis show that the glass transition temperature (Tg) shifted to a higher temperature with the increase of isocyanate level when more water was used as chemical blowing agent.

关键词： polyether polyol, polyurethane rigid foam, compressive strength, dimensional stability, cell size, glass transition temperature.

A NOTE ON THE CONSISTENCY OF LS ESTIMATES IN LINEAR MODELS

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Chinese Annals of Mathematics,Series B 2001年第4期22卷 471-474页

作者： CHEN XIRU The graduate school at {2., University of Science and Technology of{3., beijing 10003.,{3.. The graduate school at {2. University of Science and Technology of China Beijing 100039 China

It is well known that when the random errors are iid. with finite variance, the week and the strong consiStency of LS estimate of multiple regression coefficients are equivalent. This note, by constructing a counter-example, shows that this equivalence no longer holds true in case that the random errors possess only the r-th moment with 1≤5 T ＜ 2.

关键词： Linear regression model Consistency LS estimate