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The gravitational gradient tensor’s invariants and the related boundary conditions

Science china Earth Sciences 2010年第5期53卷 781-790页

作者： YU JinHai1,2,3 & ZHAO DongMing4.1 College of Earth Science, Graduate University of Chinese Academy of Sciences, Beijing 10004., china 2 Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 4.0077, china 3 State Key Laboratory of Astronautic Dynamics, Xi’an 71004., china 4.zhengzhou Institute of Surveying and Mapping, zhengzhou 4.0052, china College of Earth Science Graduate University of Chinese Academy of Sciences Beijing China Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China State Key Laboratory of Astronautic Dynamics Xi’an China zhengzhou Institute of Surveying and Mapping Zhengzhou China

Here we report new approaches of recovering the Earth gravitational field from GOCE (Gravity field and steady-state Ocean Circulation Explorer) gradiometric data with the help of the gradient tensor’s invariants. Our results only depend on GOCE satellite’s position and gradiometry, in other words, they are completely independent of the satellite attitude. First, starting from the invariants, linearization models are established, which can be referred as the general boundary conditions on the satellite’s orbit. Then, the spherical approximation expressions for the models are derived, and the corresponding solving methods for them are discussed. Furthermore, considering effects of J2-term, the spherical approximation models are improved so that the accuracies of the boundary conditions can be theoretically raised to O ( J 2/2 T), which is approximately equivalent to O(T2). Finally, some arithmetic examples are constructed from EGM96 model based on the derived theories, and the computational results illustrate that the spherical models have accuracies of 10-7 and the order recovering the gravitational field can reach up to 200, and the models with regard to effect of J2-term have accuracies of 10-8 and the order can reach up to 280.

关键词： the Earth’s gravitational field gravitational gravidiometry tensor’s invariant

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Synthesis of N^6-Cyclopropy1-2,6-diamino-9 β-D-arabinofuranosylpurine

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Chinese Chemical Letters 1999年第5期10卷 357-360页

作者： Jun Biao CHANG Rut Yun GUO Juan HE Rong Fend CHEN (Henan Institute of Chemistry. zhengzhou 450003. Henan Institute of Chemistry Zhengzhou 450003 China

Synthesis of N6-cyclopropy1-2.6-diamino-9 β-D-arabinofuranosyl-purine has beenaccomplished by treatment silylated 2-amino-6-chloro-purine 4.with 2.3.5-tri-O-benzyl- β-Darabinofuranosyl chloride 3 in the presence of molecular sieves. followed by reaction withcyclopropylamine and debenzyl reaction to give the β-anomeric nucleoside. The structures ofall products were confirmed by UV. 'H-NMR and elemental analysis.

关键词： Cyclopropylamine arabinofuranose purnie

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Explicit Solutions for a (2+1)-Dimensional Toda Lattice with Two Discrete Variables

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Communications in Theoretical Physics 2007年第10期48卷 667-670页

作者： WANG Zheng-Yan YANG Xiao Department of Mathematics,zhengzhou University,zhengzhou 4.0052,china Department of Mathematics Zhengzhou University

An integrable(2+1)-dimensional Toda lattice with two discrete variables is investigated again,which isproduced from a compatible condition of the Lax *** Darboux transformation for its spectral problems is *** an appl... 详细信息

关键词： Toda lattice two discrete variables Darboux transformation explicit solution

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Classification of hypersurfaces with parallel Mobius second fundamental form in S^(n+1)

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Science china Mathematics 2004年第3期47卷 417-430页

作者： HU Zejun LI Haizhong Department of Mathematics, zhengzhou University zhengzhou 4.0052, china Department of Mathematical Sciences, Tsinghua University, Beijing 100084. china Department of Mathematics Zhengzhou University Zhengzhou China Department of Mathematical Sciences Tsinghua University Beijing China

Let Mn(n≥2) be an immersed umbilic-free hypersurface in the(n+1)-dimensional unit sphere Sn+1. Then Mn is associated witha so-called M(o)bius metric g, and a M(o)bius second fundamental form Bwhich are invariants of Mn under the M(o)bius transformation groupof Sn+*** this paper, we classify all umbilic-free hypersurfaces withparallel M(o)bius second fundamental form.

关键词： parallel Mobius second fundamental form,hypersurface, Mobius metric, Mobius equivalence.

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The lepton flavor violating signal of the extra gauge boson Z′in photon-photon collision at the ILC

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Science china(Physics,Mechanics & Astronomy) 2010年第11期53卷 1992-1997页

作者： LIU GuoLi 1,2 1 Physics Department,zhengzhou University,zhengzhou 4.0001,china 2 Kavli Institute for Theoretical Physics china,Chinese Academy of Sciences,Beijing 100190,china zhengzhou University Physics Department Zhengzhou China (GRID:grid.207374.5) (ISNI:***) Chinese Academy of Sciences Kavli Institute for Theoretical Physics China Beijing China (GRID:grid.9227.e) (ISNI:***)

The hitherto unconstrained lepton flavor mixings,induced by the new gauge boson Z ,which are the prediction of many new physics models,such as topcolor-assisted technicolor (TC2) models and flavor-universal TC2 models,may lead to the lepton flavor violating productions of τμˉ,τeˉ and μeˉ in photon-photon collision at the proposed International Linear Collider (ILC).Through a comparative analysis of these processes,we find that the better channel to probe the new physics models is the production of τμˉ or τeˉ which occurs at a much higher rate than μeˉ production due to the large mixing angle and the large flavor changing coupling,and may reach the detectable level of the ILC for a large part of the parameter *** the rates predicted by the Standard Model are far below the detectable level,these processes may serve as a sensitive probe for such new physics models.

关键词： new gauge boson Z lepton flavor violating processes photon-photon

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Two-step interface and velocity inversion—— Study o e of the Tangshan seismic region

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Acta Seismologica Sinica(English Edition) 1998年第6期11卷 34-44页

作者： XIAO LING LAI XIAN KANG ZHANG XU YAO ZHENG Research Center of Exploration Geophysics, china Seismological Bureau, zhengzhou 450003. china

This paper studies the computation method of two step inversion of interface and velocity in a region. The 3 D interface is described by a segmented incomplete polynomial; while the reconstruction of 3 D velocity is accomplished by the principle of least squares in functional space. The computation is carried out in two steps. The first step is to inverse the shape of 3 D interface; while the second step is to do 3 D velocity inversion by distributing the remaining residual errors of travel time in accordance with their weights. The data of seismic sounding in the Tangshan Luanxian seismic region are processed, from which the 3 D structural form in depth of the Tangshan seismic region and the 3 D velocity distribution in the crust below the Tangshan Luanxian seismic region are obtained. The result shows that the deep 3 D structure in the Tangshan seismic region trends NE on the whole and the structure sandwiched between the NE trending Fengtai Yejituo fault and the NE trending Tangshan fault is an uplifted zone of the Moho. In the 3 D velocity structure of middle lower crust below that region, there is an obvious belt of low velocity anomaly to exist along the NE trending Tangshan fault, the position of which tallies with that of the Tangshan seismicity belt. The larger block of low velocity anomaly near Shaheyi corresponds to a denser earthquake distribution. In that region, there is an NW trending belt of high velocity anomaly, probably a buried fault zone. The lower crust below the epicentral region of the Tangshan M S=7.8 earthquake is a place where the NE trending belt of low velocity anomaly meets the NW trending belt of high velocity anomaly. The two sets of structures had played an important role in controlling the preparation and occurrence o

关键词： two step interface and velocity inversion 3 D velocity pattern of crust below Tangshan seismic region seismicity zone

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Constructing quantum error correcting code via logic function

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Science china(Information Sciences) 2010年第3期53卷 515-523页

作者： ZHONG ShuQin, MA Zhi & XU YaJie zhengzhou Institute of Information Engineering, University of Information Engineering of china, zhengzhou 4.0002, china zhengzhou Institute of Information Engineering University of Information Engineering of China

We present a systematic way to construct p-ary quantum error correcting codes using logic functions. As a consequence, for a given function with APC distance d′ 2, we can construct quantum codes with parameters ((n, K, d))p and gain a lower bound of K for all 2 d d′. The basic states of the constructed quantum codes can be stated and the sufficient conditions for saturating quantum Singleton bound are also discussed. We give quantum codes [[5, 1, 3]]p with p prime, [[6, 0, 4.], [[6, 2, 3]]p with p > 2 prime and [[2n, 2n - 2, 2]] as examples constructed in this way.

关键词： quantum error-correcting code logic states APC distance

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基于磁感的变压器和感应电机等效矢量磁路分析

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电工技术学报 2024年第15期39卷 4697-4707页

作者：程明马钲洲王政秦伟花为东南大学电气工程学院南京210096

电机学等传统电机理论对变压器和感应电机的工作机理分析多采用等效电路的方法,将实际磁量等效为电量来表示,在一定程度上让二者的分析变得复杂化。可是,传统磁路理论中仅有磁阻元件,难以定量表征磁通与磁动势之间存在的相位差和铁心中... 详细信息

电机学等传统电机理论对变压器和感应电机的工作机理分析多采用等效电路的方法,将实际磁量等效为电量来表示,在一定程度上让二者的分析变得复杂化。可是,传统磁路理论中仅有磁阻元件,难以定量表征磁通与磁动势之间存在的相位差和铁心中的损耗等,进而成为分析的瓶颈。为此,该文引入新的磁路参数——磁感,并利用磁阻和磁感双元件构成的矢量磁路理论,建立适用于变压器和感应电机分析的等效矢量磁路,推导了不同工况下的磁路方程,并以变压器为例,从磁路角度绘制了相量图。对变压器和感应电机在不同工况下的主要特性进行定量计算,通过实验结果验证了分析方法的有效性。相较于等效电路分析方法,该文所提的等效矢量磁路分析方法省去了匝数归算、频率归算等过程,因而概念清晰、计算简洁。该文研究不仅为电机等电磁装备的分析设计提供了全新的方法,而且有望推动《电机学》教材的改革,降低电机学相关内容的学习难度。

关键词：磁感等效磁路矢量磁路理论变压器感应电机电机学

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Weighted norm inequalities for the multilinear Calderón-Zygmund operators

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Science china Mathematics 2010年第7期53卷 1859-1872页

作者： HU GuoEn Department of Applied Mathematics, zhengzhou Information Sciences and Technology Institute,zhengzhou 4.0002, china Department of Applied Mathematics Zhengzhou Information Sciences and Technology Institute

In this paper, by proving some suitable weighted endpoint estimates, and then by multilinear interpolation and a new multilinear extrapolation lemma, the author establishes some weighted estimates for the multilinear ... 详细信息

关键词： multilinear Calderón-Zygmund operator commutator weighted norm inequality interpolation extrapolation

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A Novel Sesquiterpene Polyol Ester from Celastrus Angulatus and its Antitumor Activities

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Chinese Chemical Letters 1999年第6期10卷 487-490页

作者： Wei Ping YIN Tian Zeng ZHAO Ling Jie GAO Da Peng ZOU Jian Xun KANG(Institute of Chemistry,Henan Academy of Sciences zhengzhou 450003.Centre of Instrumental Analysis. zhengzhou University. zhengzhou {4.0052) Institute of Chemistry Henan Academy of Sciences Zhengzhou 450003 China Centre of Instrumental Analysis Zhengzhou University Zhengzhou 450052 China

A new sesquiterpene polyol ester was isolated from the leaves of Celastrus angulatus. Its structure was determined as 1 (beta), 2 (beta), 9 (a) -triacetoxy-8 (a) -((a) -hydroxyl-isobutyryloxy)-15-benzoyloxy-4.(a) -hydroxy-dihydroagarofuran by means of NMR, MS and IR spectral analysis. Preliminary biological study on antitumor activity revealed that this compound showed strong nonselective cytotoxicity against four of the NCI panel cell lines.

关键词： Celastrus angulatus sesquiterpene polyol ester NMR antitumor activities

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