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排序方式: 共有2182条查询结果,搜索用时 15 毫秒
201.
Li Hongyu 《Annals of Differential Equations》2005,21(2):153-160
By using topological method, we study a class of boundary value problem for a system of nonlinear ordinary differential equations. Under suitable conditions, we prove the existence of positive solution of the problem. 相似文献
202.
A new fixed point theorem and its applications 总被引:4,自引:0,他引:4
Xian Wu 《Proceedings of the American Mathematical Society》1997,125(6):1779-1783
In this paper, we first give a new fixed theorem of lower semicontinuous multivalued mappings, and then, as its applications we obtain some new equilibrium theorems for abstract economies and qualitative games.
203.
We prove that smooth maps are dense in the sense of biting convergence in W
1, 1(M, N) when M and Nare compact Riemannian manifolds and N is closed. 相似文献
204.
拓扑分子格本身没有层次结构,为其构造某种层次成为很重要的问题。本文的构思是赋于分子格上的拓扑一种层次,从而使拓扑分子格具有丰富的层次性,其次讨论了保层次序同态与赋层积拓扑分子格,在此基础上建立了较理想的拓扑分子格的紧性。 相似文献
205.
G. Tuchscherer 《Tetrahedron letters》1993,34(52):8419-8422
A chemoselective ligation via oxime bond formation is used for the chemical synthesis of template assembled peptides according to the TASP (Template Assembled Synthetic Proteins) approach. Aminooxyacetylation of the multifunctional partial sequence Lys- Arg- Asp- Ser of lactoferrin and subsequent condensation in aqueous solution with a topological template containing four selectively addressable aldehyde functions as attachment sites gives readily access to the TASP molecule. 相似文献
206.
L—Fuzzy拓扑空间中的可数F紧性与几乎可数F紧性 总被引:1,自引:0,他引:1
本文在L-uzzy拓扑空间中引入可数F紧性与几乎可数F紧性的概念,并讨论了它们的性质及其相互关系。 相似文献
207.
The density functional theory (DFT) method (GAUSSIAN-98 software, B3LYP functional, 6-311G(d,p) basis set) was used to calculate the spatial and electronic structures of a series of trichlorogermanes with the general formula Cl3GeCH2YC(O). AIM calculations gave the topological characteristics of the Ge-O dative bonds of these molecules. Analysis of the results showed that Ge and O atoms interact as closed-shell atoms and that the major contribution to Ge-O bonding is from Coulomb interaction between the germanium and oxygen atoms charged in the opposite sense. 相似文献
208.
In this paper we examine the interactions between the topology of certain linearly ordered topological spaces (LOTS) and the properties of trees in whose branch spaces they embed. As one example of the interaction between ordered spaces and trees, we characterize hereditary ultraparacompactness in a LOTS (or GO-space) X in terms of the possibility of embedding the space X in the branch space of a certain kind of tree. 相似文献
209.
G. Tonini F. Werner Y. Castin 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2006,39(2):283-294
We investigate theoretically the formation of a vortex lattice in
a superfluid two-spin component Fermi gas in a rotating harmonic trap, in a BCS-type
regime of condensed non-bosonic pairs.
Our analytical solution of the superfluid
hydrodynamic equations, both for the 2D BCS equation of state
and for the 3D unitary quantum gas, predicts that the vortex free gas is
subject to a dynamic instability for fast enough rotation.
With a numerical solution of the full
time dependent BCS equations in a 2D model, we confirm the existence of this dynamic
instability and we show that it leads to the formation of a regular pattern
of quantum vortices in the gas. 相似文献
210.
K. P. Schmidt A. Reischl G. S. Uhrig 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2006,38(2):343-352
In this work we give a consistent picture of the thermodynamic properties of
bosons in the Mott insulating phase when loaded adiabatically into
one-dimensional optical lattices. We find a crucial dependence of the
temperature in the optical lattice on the doping level of the Mott
insulator. In the undoped case, the temperature is of the order of the large
onsite
Hubbard interaction. In contrast, at a finite doping level the
temperature jumps almost immediately to the order of the small hopping
parameter. These two situations are investigated on the one hand by considering
limiting cases like the atomic limit and the case of free fermions. On the
other hand, they are examined using a quasi-particle conserving continuous
unitary transformation extended by an approximate thermodynamics for
hardcore particles. 相似文献