检索结果-南通市图书馆

Spectral analysis of quasi-stationary sea surface topography from GRACE mission

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china Earth sciences 2005年第11期48卷 2040-2048页

作者： ZHANG Zizhan1,2 & LU Yang1,3 1. institute of Geodesy and Geophysics, chinese academy of sciences, Wuhan 430077, china 2. Graduate School of the chinese academy of sciences, beijing 100039, china 3. Unite Center for Astro-geodymics Research, chinese academy of sciences, Shanghai 200030, china 1. institute of Geodesy and Geophysics Chinese Academy of Sciences 430077 Wuhan China 2. Graduate School of the chinese academy of sciences 100039 Beijing China 3. Unite Center for Astro-geodymics Research Chinese Academy of Sciences 200030 Shanghai China

During the last two decades satellite altimetry has offered an abundance of meas-urements of the sea surface resulting in the improvement of global mean sea surface height (MSSH) and marine geoid determination. On the other hand, with the launching of new genera-tion gravity satellites, some high accuracy long-wavelength gravity models are available. These breakthroughs give us a great opportunity for new estimation of quasi-stationary sea surface topography (QSST). In this paper, the new gravity model GGM01C derived from GRACE mission is briefly presented, and a new global high precision and high-resolution QSST is determined based on the GGM01C model and the global MSSH. The spectral features of the QSST esti-mated by GGM01C and EGM96 gravity model to degree/order 200 are discussed by spectral analysis. As a result, the QSST is mainly composed of long waves, medium waves partially and short waves scarcely, its power spectral structures are different between the zonal direction and the meridional direction, there are great differences between the two models, which maybe ex-plain why the ocean currents derived from the two gravity models by Tapley show different pat-terns.

关键词： quasi-stationary sea surface topography, mean sea surface height, GGM01, fast Fourier transform, spectral analysis

Study of the effect of atorvastatin on the interaction between ICAM-1 and CD11b by live-cell single-molecule force spectroscopy

在线全文

学校读者我要写书评

暂无评论

Science china Chemistry 2010年第4期53卷 752-758页

作者： LI Yi1, SHI XiaoLi2, LIU HuiLiang1, YI ShaoQiong3, ZHANG XueJie2 & FANG XiaoHong2 1Department of Cardiology, the General Hospital of chinese People’s Armed Police Forces, beijing 100039, china 2beijing National Laboratory for Molecular sciences institute of Chemistry, chinese academy of sciences, beijing 100190, china 3State Key Laboratory of Pathogen and Biosecurity beijing institute of Microbiology and Epidemiology, beijing 100071, china 1. Department of Cardiology the General Hospital of Chinese People’s Armed Police Forces Beijing 100039 China2. Beijing National Laboratory for Molecular Sciences Chinese Academy of Sciences Beijing 100190 China4. Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China3. State Key Laboratory of Pathogen and Biosecurity Beijing 100071 China5. Beijing Institute of Microbiology and Epidemiology Beijing 100071 China

The interaction between the cell adhesion molecule CD11b and its ligand ICAM-1 plays an important role in inflammatory responses in the disease of atherosclerosis. Atorvastatin is a commonly prescribed statin drug which has been considered as one of the most potent therapeutic agents for atherosclerosis due to its lipid-lowering effect. Recently, there is a growing body of evidence that atorvastatin has anti-inflammatory effect. We have applied the advanced method of live-cell single-molecule force spectroscopy to investigate the effect of atorvastatin on adhesion force between ICAM-1 and CD11b. Our result showed that single-molecule binding force of ICAM-1 and CD11b detected by AFM in the living cells was about 40 pN, and atorvastatin did not affect this force by blocking ICAM-1 or CD11b. This was different from the ICAM-1 monoclonal antibody, which could directly reduce the binding force of ICAM-1 and CD11b. Flow cytometry results revealed that atorvastatin pretreatment decreased the ICAM-1 expression in TNF-α activated HUVECs, which may contribute to its anti-inflammatory effect. The study provides a new approach to study anti-inflammatory mechanism for clinic drugs.

关键词： atherosclerosis atorvastatin atomic force microscopy single-molecule force spectroscopy protein-protein interaction

An efficient chiral synthesis of (R)-N-[3-acetyl-4-(2-hydroxy-3-isopropylamino-propoxy)phenyl]-butanamide with high enantioselectivity

在线全文

学校读者我要写书评

暂无评论

Science china Chemistry 2009年第8期52卷 1216-1219页

作者： WANG NaiXing1,2 & TANG XinLiang1,3 1 Technical institute of Physics and Chemistry,chinese academy of sciences,beijing 100080,china 2 College of Chemistry and Chemical Engineering,Graduate University of chinese academy of sciences,beijing 100049,china 3 School of Chemical Engineering and Environment,beijing institute of Technology,beijing 100081,china 1. Technical institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100080 China 2. College of Chemistry and Chemical Engineering Graduate University of Chinese Academy of Sciences Beijing 100049 China 3. School of Chemical Engineering and Environment Beijing Institute of Technology Beijing 100081 China

R-Enantiomer of the β-receptor antagonist N-[3-acetyl-4-(2-hydroxy-3-isopropylamino-propoxy)phenyl] butanamide with high enantioselectivity was synthesized from cheap starting materials and enantiopure chiral reagent through an efficient,convenient and practical synthetic *** product was detected by 1H NMR,13C NMR,and MS,and the enatiomeric excess was determined by chiral HPLC analysis using a chiracel AD-H column.

关键词： chiral synthesis enantioselectivity enatiomeric excess chiral HPLC analysis

Optimization of mathematical models for thematic maps

在线全文

学校读者我要写书评

暂无评论

Science china(Technological sciences) 2010年第S1期53卷 15-24页

作者： QI QingWen1,ZHANG An1,JIANG LiLi1,ZOU XiuPing2,XU Li3 & CHENG Xi1,4 1 institute of Geographical sciences and Natural Resources Research,chinese academy of sciences,beijing 100101,china 2 institute of Policy and Management,chinese academy of sciences,beijing 100080,china 3 Taishan University,Taian 271021,china 4 Graduate University of chinese academy of sciences,beijing 100049,china chinese Acad Sci Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China chinese Acad Sci Inst Policy & Management Beijing 100080 Peoples R China Taishan Univ Tai An 271021 Shandong Peoples R China chinese Acad Sci Grad Univ Beijing 100049 Peoples R China

The thematic map is a major class of maps designed to demonstrate particular features or concepts,functioning as an indispensable tool in geographical *** process of thematic mapping is one into which geographical research goes deeply and *** key activity and course of thematic map production is the use of mathematical models to create thematic data ***,the selection and optimization of mathematical models is in the forefront of thematic map *** theoretical foundations,mechanisms and methods of mathematical model optimization are expounded in this paper,including two approaches,the phase by phase mode and the multi-aim scheme balance *** studies in eco-environment mapping and emergency mapping are described and analyzed,with a hierarchical analysis method being used in the model optimization for eco-environment fragility and sensitivity assessment mapping in Beibuwan (Guangxi) District,the dynamic system (DS) method being used in the model optimization for ecological security adjustment mapping in Xishuang Banna,Yunnan province,and the multi-phase mode being used in the models for forest fire and infectious diseases mapping.

关键词： thematic map mathematic model optimization

Some results about holomorphic vector bundles over general Hopf manifolds

在线全文

学校读者我要写书评

暂无评论

Science china Mathematics 2009年第12期52卷 2863-2866页

作者： ZHOU XiangYu institute of Mathematics,academy of Mathematics and Systems Science,and Hua Loo-Keng Key Laboratory of Mathematics,chinese academy of sciences,beijing 100190,china 1. institute of Mathematics Academy of Mathematics and Systems Science and Hua Loo-Keng Key Laboratory of Mathematics Chinese Academy of Sciences Beijing 100190 China

In the present note that grew out of my talk given at the conference in honor of Prof. Zhong Tongde,I give a survey of some recent results about holomorphic vector bundles over general Hopf manifolds.

关键词： holomorphic vector bundles Hopf manifolds cohomology groups 32L10 32L05 32J18

Reconstructing mean maximum temperature of growing season from the maximum density of the Schrenk Spruce in Yili,Xinjiang,china

在线全文

学校读者我要写书评

暂无评论

chinese Science Bulletin 2009年第13期54卷 2300-2308页

作者： CHEN Jin1,2,3,WANG LiLi1,4,5,ZHU HaiFeng1 & WU Pu1 1 institute of Geographic sciences and Natural Resources Research,chinese academy of sciences,beijing 100101,china 2 Graduate University of chinese academy of sciences,beijing 100049,china 3 institute of Vertebrate Paleontology and Paleoanthropology,chinese academy of sciences,beijing 100044,china 4 institute of Tibetan Plateau Research,chinese academy of sciences,beijing 100085,china 5 institute of Desert and Meteorology,china Meteorological Administration,ürümqi 830002,china institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate University of chinese academy of sciences Beijing 100049 China institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China institute of Desert and Meteorology China Meteorological Administration ürümqi 830002 China

To study the historical temperature variation in Yili of Xinjiang,the tree-ring chronologies of maximum density(MXD) and tree-ring width(TRW) were established with the Schrenk Spruce(Picea schrenkiana *** Mey) collected from six sites to analyze the characteristics and ability of response to climate *** results suggest that the MXD chronology of the Schrenk Spruce from different sampling sites responded to climate change well and were positively correlated with the mean maximum temperature and the mean temperature from April to August in the study *** mean maximum temperature anomaly from April to August,spanning the years from 1848 to 2000,was reconstructed by three MXD chronologies which were selected by stepwise *** reconstructed function was stable and explained 56.2% of the *** reconstructed results indicated a cold span of 153 years in spring and summer from the beginning of the 1950s to the beginning of the 1970s in the Yili *** strongly increasing tendency was detected in the mean maximum temperature anomaly from April to August during this reconstructed period.

关键词：平均最高气温伊犁谷地最大密度云杉胡杨生长季节新疆树木年轮宽度

Chronology of Holocene lacustrine sediments in Co Ngoin, central Tibetan Plateau

在线全文

学校读者我要写书评

暂无评论

Science china Earth sciences 2006年第9期49卷 991-1001页

作者： WU Yanhong1, WANG Sumin1& HOU Xinhua1,3 1. Key Laboratory of Lake Sedimentation and Environment, Nanjing institute of Geography and Limnology, chinese academy of sciences, Nanjing 210008, china 2. institute of Tibetan Plateau Research, chinese academy of sciences, beijing 10085, china 3. Graduate University of chinese academy of sciences, beijing 100039, china 1. Key Laboratory of Lake Sedimentation and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China 2. institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 10085 China 3. Graduate University of chinese academy of sciences Beijing 100039 China

Chronology is the basis for using lacustrine sediments to reconstruct the history of en-vironmental change. Radioactive-nuclides such as 14C, 210Pb and 137Cs dating are mainly used to establish the chronology for recent several ten thousand years. Because of being mixed with “dead carbon”, the measured 14C age is always older than the actual age which is recognized as “reservoir effect”. Cs is a kind of active metal element, and easy to migrate vertically in the sediment that leads to the error of the time marker. 210Pb dating should make sure to select CIC model or CRS model. On the Tibetan Plateau, most of the lakes are alkaline closed lake where Cs is more moveable in the sediment and the reservoir effect caused by “dead carbon” on 14C dating is stronger. Based on the analysis on results of 14C, 210Pb and 137Cs of the lacustrine sediments from Co Ngoin, central Tibetan Plateau, we use the simple regression method to re-calculate the 14C calendar ages, and establish the time sequence for cores CE-1 and CE-2 with result of 210Pb CRS model for the upper 35 cm and re-calculated 14C calendar age for sediments bellow 35 cm. Since 1400 cal. a BP, sedimentation inter-rupted for more than 1000 years. According to this time sequence, variations of environmental proxies confidently reflect the major climatic events in Holocene.

关键词： 14C, 210Pb and 137Cs, chronology, lacustrine sediments, climatic event, Co Ngoin, central Tibetan Plateau.

FUZZY-BASED NETWORK BANDWIDTH DESIGN UNDER DEMAND UNCERTAINTY

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2010年第1期23卷 61-70页

作者： Lean YU Wuyi YUE Shouyang WANG institute of Systems Science MADIS Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijiny 100190 China Department of Intelligence and Informatics Konan University Kobe 658-8501 Japan. institute of Systems Science MADIS Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China.

In communication networks （CNs）, the uncertainty is caused by the dynamic nature of the traffic demands. Therefore there is a need to incorporate the uncertainty into the network bandwidth capacity design. For this purpose, this paper developed a fuzzy methodology for network bandwidth design under demand uncertainty. This methodology is usually used for offiine traffic engineering optimization, which takes a centralized view of bandwidth design, resource utilization, and performance evaluation. In this proposed methodology, uncertain traffic demands are first handled into a fuzzy number via a fuzzification method. Then a fuzzy optimization model for the network bandwidth allocation problem is formulated with the consideration of the trade-off between resource utilization and network performance. Accordingly, the optimal network bandwidth capacity can be obtained by maximizing network revenue in CNs. Finally, an illustrative numerical example is presented for the purpose of verification.

关键词： Communication networks demand uncertainty fuzzy set theory network bandwidth design network optimization.

UNCONSTRAINED METHODS F0R GENERALIZED NONLINEAR COMPLEMENTARITY AND VARIATIONAL INEQUALITY PROBLEMS

在线全文

学校读者我要写书评

暂无评论

Journal of Computational Mathematics 1996年第2期14卷 99-107页

作者： J.M. Peng(LSEC institute of Computational Mathematics and Scientific/Engineering Cmputing,chinese academy of sciences, beijing, china) 中科院计算数学与科学工程计算所北京

In this papert we construct unconstrained methods for the generalized nonlinearcomplementarity problem and variational inequalities. Properties of the correspon-dent unconstrained optimization problem are studied. We apply these methods tothe subproblems in trust region method, and study their interrelationships. Nu-merical results are also presented.

关键词： Math UNCONSTRAINED METHODS F0R GENERALIZED NONLINEAR COMPLEMENTARITY AND VARIATIONAL INEQUALITY PROBLEMS