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Characterization for commutators of n-dimensional fractional Hardy operators

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science china Mathematics 2007年第10期50卷 1418-1426页

作者： Zun-wei FU~(1,2) Zong-guang LIU~3 Shan-zhen LU~(1+) Hong-bin WANG~3 ~1 School of Mathematical sciences,beijing normal university,beijing 100875,china ~2 Department of Mathematics,Linyi normal university,Linyi 276005,china ~3 Department of Mathematics,china university of Mining and technology (beijing),beijing 100083,china School of Mathematical sciences Beijing Normal University Beijing China Department of Mathematics Linyi Normal University Linyi China Department of Mathematics China University of Mining and Technology (Beijing) Beijing China

In this paper,it was proved that the commutator H_(β,b)generated by an n-dimensional fractional Hardy operator and a locally integrable function b is bounded from L^(p1)(R^n)to L^(p2)(R^n)if and only if b is a CMO(R^... 详细信息

关键词： n-dimensional fractional Hardy operator, commutator, C(M)O function, homogeneous Herz space

A five-fold pig bacterial artificial chromosome library:a resource for positional cloning and physical mapping

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Progress in Natural science:Materials International 2006年第08期16卷 889-892页

作者： LIU Wei, ZHANG Ying, LIU Zhaoliang, GUO Li, WANG Xiaobo, FEI Jing, FENG Jidong, ZHAO Rui, HU Xiaoxiang and LI Ning (The State Key Laboratory for Agro-Biotechnology, college of Biology, china Agricultural university, beijing 100094, china college of Animal science and technology, china Agricultural university, beijing 100094, china) The State Key Laboratory for Agro-Biotechnology College of Biology China Agricultural University Beijing 100094 China. college of Animal science and technology China Agricultural University Beijing 100094 China

A pig BAC library was constructed with genomic DNA from a male Erhualian pig. After partial digestion with HindⅢor BamHⅠthe fragments obtained were cloned into the pBeloBAC11 vector. The library consists of 184320 clones which stored in 480 pieces 384-well plates (20 plates per superpool). A two-step 4-dimension PCR screening system was established to screen the positive clones. An average insert size of 128 kb was estimated from 105 randomly isolated clones, which indicates that the library is more than five times of genomic coverage. For the demonstration of the probability to pick out any unique genes or DNA markers from the library, 10 single-copy genes were screened out and the positive clones were yielded between 1 and 8 with an average of 3.6. Positive superpools were obtained for 32 microsatellite markers selected from different regions of pig genome. The number of positive superpools for each marker varies from 1 to 9 with an average of 4.78. This BAC library provides an additional resource for pig physical mapping and gene identifica-

关键词： pig BAC library PCR screening system.

Structure of cis-[Pt(NH_(3))(2-picoline)]^(2+)and DNA adduct and its bonding characteristics

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science china Chemistry 2004年第1期47卷 67-74页

作者： JIA Muxin, LIU Kai, YANG Zuoyin & CHEN GuangjuDepartment of Chemistry, beijing normal university, beijing 100875, china beijing General Research Institute of Mining and Metullargy, beijing 100044, china Department of Chemistry Beijing Normal University Beijing China beijing General Research Institute of Mining and Metullargy Beijing China

Several methods including molecular mechanics, molecular dynamics, ONIOM that combines quantum chemistry with molecular mechanics and standard quantum chemistry are used to study the configuration and electron structures of an adduct of the DNA segment d(ATACATG*G*TACATA)·d(TATGTACCATGTAT) with cis-[Pt(NH3)(2-Picoline)]2+. The investigation shows that the configuration optimized by ONIOM is similar to that determined by NMR. Strong chemical bonds between Pt of the complex and two N7s of neighboring guanines in the DNA duplex and hydrogen bond between the NH3 of the complex and O6 of a nearby guanine have a large impact on the configuration of the adduct. Chemical bonds, the aforementioned hydrogen bond, and the interaction between a methyl of the complex and a methyl of the base in close proximity are critical for the complex to specifically recognize DNA.

关键词： cis-[PtCl2(NH3)(2-Pic)], DNA segment, ONIOM, molecular mechanics, molecular dynamics.

Estimation methods of eco-environmental water requirements: Case study

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science china Earth sciences 2005年第8期48卷 1280-1292页

作者： YANG Zhifeng1,2, CUI Baoshan1 & LIU Jingling 1. School of Environment, beijing normal university, beijing 100875, china 2. State Key Joint Laboratory of Environmental Simulation and Pollution Control, beijing 100875, china School of Environment Beijing Normal University Beijing China State Key Joint Laboratory of Environmental Simulation and Pollution Control Beijing China

Supplying water to the ecological environment with certain quantity and quality is significant for the protection of diversity and the realization of sustainable development. The conception and connotation of eco-environmental water requirements, including the definition of the conception, the composition and characteristics of eco-environmental water requirements, are evaluated in this paper. The classification and estimation methods of eco-environmental water requirements are then proposed. On the basis of the study on the Huang-Huai-Hai Area, the present water use, the minimum and suitable water requirement are estimated and the cor-responding water shortage is also calculated. According to the interrelated programs, the eco-environmental water requirements in the coming years (2010, 2030, 2050) are estimated. The result indicates that the minimum and suitable eco-environmental water requirements fluc-tuate with the differences of function setting and the referential standard of water resources, and so as the water shortage. Moreover, the study indicates that the minimum eco-environmental water requirement of the study area ranges from 2.84×1010m3 to 1.02×1011m3, the suitable water requirement ranges from 6.45×1010m3 to 1.78×1011m3, the water shortage ranges from 9.1×109m3 to 2.16×1010m3 under the minimum water requirement, and it is from 3.07×1010m3 to 7.53×1010m3 under the suitable water requirement. According to the different values of the water shortage, the water priority can be allocated. The ranges of the eco-environmental water re-quirements in the three coming years (2010, 2030, 2050) are 4.49×1010m3?1.73×1011m3, 5.99×10m3?2.09×1011m3, and 7.44×1010m3?2.52×1011m3, respectively.

关键词： eco-environmental water requirements, assessment methods, Huang-Huai-Hai area.

Analysis of china’s Water Security and Virtual Water Trade

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Chinese Journal of Population,resources and Environment 2006年第4期4卷 18-23页

作者： Wang Hongrui1,2,Liu Xinghan3,Dong Yanyan1,2,Wang Junhong1,2 1.college of Water sciences,beijing normal university,beijing 100875,china 2.Key Laboratory for Water and Sediment sciences Ministry of Education,beijing 100875,china 3.college of Economics&Management,beijing university of technology,beijing 100022,china college of Water sciences Beijing Normal University Key Laboratory for Water and Sediment sciences Ministry of Education

Producing goods and services all needs water *** water used in the process of an agricultural or industrial product is called the"Virtual Water"contained in this product. Through international trade,water-scarce countries and regions could purchase water-intensive products--especially foods,from water-rich countries to balance their water deficits and achieve water *** is one of the 13 most water-deficit countries whose water safety have been severely *** paper generalized the recent global research development and made a brief introduction about the methods calculating virtual water content in specific *** a case study,we qualified china's annual virtual water flows from year 2000 to 2002 with trade in crops,and ended with some policy advice for application and practice of virtual water strategy.

关键词： water security virtual water virtual water trade crops

A POSTERIORI ERROR ANALYSIS OF NONCONFORMING METHODS FOR THE EIGENVALUE PROBLEM

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Journal of Systems science & Complexity 2009年第3期22卷 495-502页

作者： Youai Licollege of Computer and Information Engineering, beijing technology and Business university, beijing100048,china. college of Computer and Information Engineering Beijing Technology and Business University

This paper extends the unifying theory for a posteriori error analysis of the nonconformingfinite element methods to the second order elliptic eigenvalue *** particular,the authorproposes the a posteriori error estimator for nonconforming methods of the eigenvalue problems andprove its reliability and efficiency based on two assumptions concerning both the weak continuity andthe weak orthogonality of the nonconforming finite element spaces,*** addition,the authorexamines these two assumptions for those nonconforming methods checked in literature for the Laplace,Stokes,and the linear elasticity problems.

关键词： A posteriori error analysis eigenvalue problem nonconforming finite element.

Shell effect and capture cross sections in the synthesis of superheavy nuclei

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science china(Physics,Mechanics & Astronomy) 2009年第10期52卷 1489-1493页

作者： DU SaiSai1,2,BIAN BaoAn1,2,3,LIU Min1,2,4,FENG ZhaoQing5,6 & ZHANG FengShou1,2,6 1 Key Laboratory of Beam technology and Material Modification of Ministry of Education,college of Nuclear science and technology,beijing normal university,beijing 100875,china 2 beijing Radiation Center,beijing 100875,china 3 School of science,Jiangnan university,Wuxi 214122,china 4 college of Physics and technology,Guangxi normal university,Guilin 541004,china 5 Institute of Modern Physics,Chinese Academy of sciences,Lanzhou 730000,china 6 Center of Theoretical Nuclear Physics,National Laboratory of Heavy Ion Accelerator of Lanzhou,Lanzhou 730000,china Key Laboratory of Beam technology and Material Modification of Ministry of Education College of Nuclear Science and Technology Beijing Normal University Beijing China beijing Radiation Center Beijing China School of science Jiangnan University Wuxi China college of Physics and technology Guangxi Normal University Guilin China Institute of Modern Physics Chinese Academy of Sciences Lanzhou China Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou China

The shell effect is included in the improved isospin dependent quantum molecular dynamics model in which the shell correction energy of the system is calculated by using the deformed two-center shell model. A switch function is introduced to connect the shell correction energy of the projectile and the target with that of the compound nucleus during the dynamical fusion process. It is found that the calculated capture cross sections reproduce the experimental data quantitatively at the energy near the Coulomb barrier. The capture cross sections for reaction 35 80 Br + 82 208 Pb → 117 288 X are also calculated and discussed.

关键词： superheavy nuclei transport theory shell effect cross sections

ON THE LEAST SQUARES PROBLEM OF A MATRIXEQUATION

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Journal of Computational Mathematics 1999年第6期17卷 589-594页

作者： An-ping Liao(college of science, Hunan normal university, Changsha 410081, china) 湖南师范大学理学院湖南长沙 410081

Least squares solution of F=PG with respect to positive semidefinite symmetric P is considered,a new necessary and sufficient condition for solvablity is given,and the expression of solution is derived in the some special cases. Based on the expression, the least spuares solution of an inverse eigenvalue problem for positive semidefinite symmetric matrices is also given.

关键词： least squares solution matrix equation inverse eigenvalue problem positive semidefinite symmetric matrix

Compatibility between glass sealants and electrode materials of solid oxide fuel cells

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Rare Metals 2008年第4期27卷 378-383页

作者： PIAO Jinhua SUN Kening Chen Xinbing Department of Applied Chemistry Harbin Insstnte of Technology Harbin 150001 China Department of Materials science and Engineering Beijing Normal University Beijing 100875 China

BaO-CaO-Al2O3-SiO2-La2O3-B2O3 system glass materials were investigated as sealants for a solid oxide fuel cell （SOFC）. The transition temperature （Tg and the crystal temperature （Td） values decrease greatly with the increase of BaCO3 content when the other components do not change. For the thermal expansion coefficient （TEC） values, the trend is inverse. The sealant has superior thermal expansion coefficient matching properties with La（Sr）MnO3 （LSM） cathode, La（Sr）FeO3 （LSF） cathode, Ni-LDC （La doped CeO2） anode, and Ni-YSZ （yttria stabilized zirconia） cermet anode. The sealant also has superior stability, compatibility, and good bonding characteristic with these electrode materials at 800-900℃. The results indicate that the aluminosilicate system glass sealant possesses superior compatibility with electrode materials of the solid oxide fuel cell

关键词： solid oxide fuel cell aluminosilicate sealant glass-ceramic compatibility interface