检索结果-南通市图书馆

Extremal problems on the Hua domain of the first type

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 Mathematics 2005年第z1期48卷 343-354页

作者： SU Jianbing & YIN Weiping Mathematics department, Xuzhou normal university, Xuzhou 221116,{3. Mathematics department, Capital normal university, Beijing 10003.,{3. 1. Mathematics department Xuzhou Normal University 221116 Xuzhou China 2. Mathematics department Capital Normal University 100037 Beijing China

In this paper we study some extremal problems between the Hua domain of the first type and the unit ball.

关键词： extremal problem, Hua domain of the first type, minimal circumscribed Hermitian ellipsoid.

Extremal problems on the generalized Hua domain of the first type

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2006年第4期16卷 352-358页

作者： SU Jianbing and YIN Weiping department of Mathematics, Xuzhou normal university, Xuzhou 221116,{3. department of Mathematics, Capital normal university, Beijing 10003.,{3. [a]department of Mathematics Xuzhou Normal University Xuzhou China [b]department of Mathematics Capital Normal University Beijing China

Some extremal problems between the generalized Hua domain of the first type and the unit ball are studied. The extremal mapping and extremal value in explicit formulas are also obtained.

关键词： extremal problem generalized Hua domain of the first type minimal circumscribed Hermitian ellipsoid.

Congruences on ideal nil-extension of completely regular semigroups

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1998年第5期43卷 379-381页

作者： REN Xueming 1, 2 GUO Yuqi 2 and CEN Jiaping (Shum Kar-ping) 3.. department of Mathematics, Xi’an university of Architecture & Technology, Xi’an 710055, china 2. department of Mathematics, Yunnan university, Kunming 650091, china 3. department of department of Mathematics Xi’an University of Architecture & Technology Xi’an China department of Mathematics Yunnan University Kunming China department of Mathematics Chinese University of Hong Kong Hong Kong

Let S be an ideal nil-extension of a completely regular semigroup K by a nil semigroup Q with zero. A concept of admissible congruence pairs (δ,ω) of S is introduced, where δ and ω are a congruence on Q and a congruence on K respectively. It is proved that every congruence on S can be uniquely respresented by an admissible congruence pair (δ,ω) of S. Suppose that ρ K denotes the Rees congruence induced by the ideal K of S. Then it is shown that for any congruence σ on S,a mapping Γ:σ|→(σ Q,σ K) is an order-preserving bijection from the set of all congruences on S onto the set of all admissible congruence pairs of S,where σ K is the restriction of σ to K and σ Q=(σ∨ρ K)/ρ K. Moreover,the lattice of congruences of S is also discussed. As a special case,every congruence on completely Archimedean semigroups S is described by an admissible quarterple of S. The following question is asked: Is the lattice of congruences of the completely Archimedean semigroup a semimodular lattice?

关键词： completely regular semigroups ideal nil-extension congruences.

Local and non-local sources of airborne particulate pollution at Beijing——The ratio of Mg/Al as an element tracer for estimating the contributions of mineral aerosols from outside Beijing

在线全文

学校读者我要写书评

暂无评论

Science china Chemistry 2005年第3期48卷 253-264页

作者： HAN Lihui1, ZHUANG Guoshun1,2,3. SUN Yele1 & WANG Zifa3.1. The Center for Atmospheric Environmental Study, department of Chemistry, Beijing normal university, Beijing 100875,{3. 2. Center for Atmospheric Chemistry Study, department of Environmental Science & Engineering, Fudan university, Shanghai 20043.,{3. 3. LAPC/NZC, Institute of Atmospheric physics, CAS, Beijing 100029,{3. 1. The Center for Atmospheric Environmental Study Department of Chemistry Beijing Normal University 100875 Beijing China 2. Center for Atmospheric Chemistry Study Department of Environmental Science & Engineering Fudan University 200433 Shanghai China 3. Institute of Atmospheric physics CAS LAPC/NZC 100029 Beijing China

A new element tracer technique has firstly been established to estimate the contri-butions of mineral aerosols from both inside and outside Beijing. The ratio of Mg/Al in aerosol is a feasible element tracer to distinguish between the sources of inside and outside Beijing. Mineral aerosol, inorganic pollution aerosol mainly as sulfate and nitrate, and organic aerosol are the major components of airborne particulates in Beijing, of which mineral aerosol accounted for 3.%―67% of total suspended particles （TSP）, 10%―70% of fine particles （PM2.5）, and as high as 74% and 90% of TSP and PM2.5, respectively, in dust storm. The sources from outside Beijing contributed 62% （3.%―86%） of the total mineral aerosols in TSP, 69% （52%―90%） in PM10, and 76% （59%―93.） in PM2.5 in spring, and 69% （52%―83.）, 79% （52%―93.）, and 45% （7%―79%） in TSP, PM10, and PM2.5, respectively, in winter, while only20% in summer and autumn. The sources from outside Beijing contributed as high as 97% during dust storm and were the dominant source of airborne particulates in Beijing. The contributions from outside Bei-jing in spring and winter are higher than those in summer, indicating clearly that it was related to the various meteorological factors.

关键词： mineral aerosol local sources non-local sources dust storm re-suspended dust element tracer technique.

B→Xsγ, Xsl+l~-Decays and Constraints on Mass Insertion Parameters in MSSM

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Communications in Theoretical physics 2006年第10期46卷 687-696页

作者： XIAO Zhen-Jun,~+ LI Feng-Ying, and ZOU Wen-Jun department of physics and Institute of Theoretical physics, Nanjing {3. university, Nanjing 210097, china department of physics Nanjing Normal University Institute of Theoretical physics Nanjing Normal University

In this paper, we study the upper bounds on the mass insertion parameters (δ~q)in the minimal supersymmetric standard model. We found that the information from the measured branching ratio of B→Xl+l~-decaycan help us to improve the upper bounds on the mass insertions parameters(δ. Some regions allowed by thedata of Br(B→Xγ)are excluded by the requirement of an SM-like C(m)imposed by the data of Br(B→Xl+l~-).

关键词： B meson decay the minimal supersymmetric standard model mass insertion

Analytical theory of flexural behavior of concrete beam reinforced with textile-combined steel

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(Technological Sciences) 2010年第6期53卷 1700-1710页

作者： XU ShiLang & YIN ShiPing department of Civil Engineering,dalian university of Technology,dalian 116024,china 1. department of Civil Engineering Dalian University of Technology Dalian 116024 China

Textile-reinforced concrete (TRC) is a new high performance cementitious composite material,which not only has superior corrosion resistance but also can effectively limit the development of concrete cracks and make the crack width and spacing of concrete become ***,due to the brittle feature of fiber materials,the TRC structural member has no distinct failure symptom when it arrives at its ultimate *** the same time,ordinary reinforced concrete (RC) elements have large dead weight and can not efficiently restrict the expansion of the main crack of structures because of the restriction of their special cover *** order to overcome the disadvantages of both the TRC and the RC,a new architecture reinforced with textile-combined steel is proposed in this study,making full use of the advantages of the above two *** cover concrete at the tension zone of an RC element is partially replaced with TRC and thus the steel reinforcements replaced with textiles are *** with the old one,the new structure has less dead weight and has the merits of service safety and good *** flexural development process of the proper beam with this new structure is investigated in this paper and based on the plane section assumption,analytical equations are derived by using nonlinear analysis theory,including the load-carrying capacity at different stages and moment-curvature relationship and mid-span deflection during the entire loading *** between the calculated and the experimental results reveals satisfactory agreement and thus verifies the feasibility of the equations.

关键词： textile-reinforced concrete limiting the crack beam reinforced with textile-combined steel flexural behavior analytical theory

Optical waveguides in LiNbO_3.and stoichiometric LiNbO_3.crystals by proton exchange

在线全文

学校读者我要写书评

暂无评论

Science china(physics,Mechanics & Astronomy) 2008年第10期51卷 1479-1488页

作者： LI ShiLing College of physics and Engineering, Qufu normal university, Qufu 273.65,{3. School of physics and Microelectronics, Shandong university, Jinan 250100,{3. 1. College of physics and Engineering Qufu Normal University Qufu 273165 China 2. School of physics and Microelectronics Shandong University Jinan 250100 China

The formation of optical planar waveguides in LiNbO3.and stoichiometric LiNbO3.crystals by proton exchange was reported. The prism-coupling method was used to characterize the dark-line spectroscopy at the wavelength of 63. and 153. nm, re-spectively. The mode optical near-field outputs from proton-exchanged LiNbO3.and SLN waveguides at 63. nm were presented. The mode field from stoichiometric LiNbO3.(SLN) waveguide is lighter and more uniform than that from LiNbO3.waveguide, which means the quality of the waveguide in SLN crystal is better than that of the LiNbO3.waveguide. For proton-exchanged LiNbO3.waveguides, the evo-lution of the refractive index profile with annealing was presented. The disorder profiles of Nb atoms in proton-exchanged LiNbO3.waveguides were obtained by Rutherford backscattering/channeling technique. It is shown that the longer the exchange time, the larger the displacement of Nb atoms.

关键词： optical waveguide proton exchange LiNbO3 crystal stoichiometric LiNbO3 crystal

ON THE VARIATIONS OF G_2

在线全文

学校读者我要写书评

暂无评论

Chinese Annals of Mathematics,Series B 2003年第3期24卷 387-394页

作者： LIU DONG LIN LEI department of Mathematics, East china normal {3., Shanghai 200062, china. department of Mathematics, East china normal {3., Shanghai 200062, china. department of Mathematics East China Normal University Shanghai 200062 China

In [1], Shen Guangyu constructed several classes of new simple Lie algebras of characteristic 2, which are called the variations of G2. In this paper, the authors investigate their derivation algebras. It is shown that G2 and its variations all possess unique nondegenerate associative forms. The authors also find some nonsingular derivations of ViG for i = 3.4, 5, 6, and thereby construct some left-symmetric structures on Vi G for i = 3.4,5,6. Some errors about the variations of sl(3. F) in [1] are corrected.

关键词： Variation Derivation Associative form Left-symmetric structure

An accurate three-dimensional potential energy surface for the He-Na_2 complex

在线全文

学校读者我要写书评

暂无评论

Science china Chemistry 2008年第6期51卷 539-544页

作者： WANG Yue,HUANG WuYing,FENG ErYin& CUI ZhiFeng department of physics,Anhui normal {3.,Wuhu 241000,china 1. department of physics Anhui Normal University Wuhu 241000 China

An accurate three-dimensional potential energy surface(PES) for the He-Na2 van der Waals comple was calculated at the coupled cluster singles-and-doubles with noniterative inclusion of connecte triple(CCSD(T)) level of theory.A mixed basis set,aug-cc-pVQZ for the He atom and cc-pCVQZ for th sodium atom,and an additional(3.3.2d1f) set of midbond functions were *** computed inte action energies in 819 configurations were fitted to a 96-parameter analytic potential model by leas squares *** PES has two shallow wells corresponding to the T-shaped structure and the linea configuration,which are located at 12.5a0 and 14 a0 with depths of 1.769 and 1.684 cm-1,respectivel The whole potential energy surface exhibits weak *** on the fitted PES,state-to-stat differential cross sections were calculated.

关键词： van der Waals complex potential energy surface ab initio calculation