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1.
首先通过集代数得到了Stone代数的表示定理,然后证明了每一个Stone代数均嵌入到某个集合X上的一个Stone映射类S中. 相似文献
2.
讨论了结构与饱和土壤相互作用的固结分析问题.对于结构利用多重子结构分析技术实现向饱和土交界面上的凝聚.从而建立了结构与饱和土壤相互作用的固结控制方程.文中给出了问题求解的一次性算法方案,采取压力主从关系的手段处理边界上的不排水条件.文末给出数值算例.本文工作为大型结构与土体相互作用固结分析研究工作的深入创造了条件. 相似文献
3.
Juan Méndez-Vivar 《Journal of Sol-Gel Science and Technology》2006,38(2):159-166
Sols composed of dibutyltin dilaureate (DTL) and tetraethyl orthosilicate (TEOS) were prepared using a mixture of methyl ethyl
ketone (MEK) and acetone as the solvent in order to study the interaction between the oligomeric Sn and Si species. The hydrolysis
molar ratio r (r=nH2O/nM (M: Si, Sn or Si+Sn) was 2. The use of an acid or basic catalyst was avoided, as the sols are intended to be used in
the formulation of potential stone consolidants. The sols were studied by several spectroscopic techniques including Small
Angle X-ray Scattering (SAXS), 29Si and 119Sn NMR, Fourier Transform Infrared (FTIR) spectroscopy and X-ray diffraction (XRD). According to the spectroscopic results
the lauric acid produced by the hydrolysis of DTL modifies the condensation path of the Si species, leading to the formation
of two types of oligomeric chains: linear swollen and multiparticle diffusion-limited aggregates, depending on the molar ratio
Sn/Si. The 29Si NMR results indicated that the hydrolysis of DTL catalizes the condensation of the Si species, giving as a result higher
condensation extents of the Si species in the Sn-Si sols compared to a pure Si sol. Based on the Radial Distribution functions
(RDF) and the FTIR results, heterocondensation occurred. 相似文献
4.
Let K and S be locally compact Hausdorff spaces and let X be a strictly convex Banach space of finite dimension at least 2. In this paper, we prove that if there exists an isomorphism T from onto satisfying then K and S are homeomorphic. Here denotes the Schäffer constant of X. Even for the classical cases , and , this result is the X‐valued Banach–Stone theorem via isomorphism with the largest distortion that is known so far, namely . On the other hand, it is well known that this result is not true for , even though K and S are compact Hausdorff spaces. 相似文献
5.
Based on the governing equations of 2D plane-strain Biot’s consolidation, the relationship between generalized displacements and stresses of a single soil layer with anisotropic permeability and incompressible fluid and solid constituents is described by an analytical layer-element, which is deduced in the Laplace–Fourier transform domain by using the eigenvalue approach. Taking the boundary conditions and the continuity of the soil layers into consideration, a global stiffness matrix is subsequently assembled and solved. As to the 3D case, the same derivation is employed after the application of a decoupling transformation. The actual solutions in the physical domain can further be acquired by inverting the Laplace–Fourier transform. Finally, numerical examples are carried out to verify the presented theory and discuss the influence of the anisotropic permeability on the consolidation behavior. 相似文献
6.
Gas sensing is one of the most promising applications for graphene. Using molecular dynamics simulation method, adsorption isotherm of xenon (Xe) gas on defected and perfect graphene is studied in order to investigate sensing properties of graphene for Xe gas. In this method, first generation of Brenner many-body potential is used to simulate the interaction of carbon–carbon (C) atoms in graphene, and Lennard–Jones two-body potential is used to simulate interaction of Xe–Xe and Xe–C atoms. In the simulated systems, adsorption coverage, radial distribution function, heat of adsorption, binding energy and specific heat capacity at constant volume are calculated for several temperatures between 90 K and 130 K, and various pressures. It was found that both of the defected and perfect graphene could be introduced as very good candidates for adsorption of Xe gas. 相似文献
7.
S. Radeleczki 《Southeast Asian Bulletin of Mathematics》2002,25(3):503-513
We prove necessary and sufficient conditions for the decomposition of an arbitrary CJ-generated algebraic lattice into a direct product of subdirectly irreducible lattices. We generalize earlier results due to F. Maeda, T. Katriák and the present author. New structure theorems for two classes of CJ-generated algebraic lattices are also obtained.AMS Subject Classification (1991) 06B05 06B10Research partially supported by Hungarian National foundation for Scientific Research, Grant No. T029525 and T030243 and by János Bolyai Grant of Hungarian Academy of Science. 相似文献
8.
Arnod S. Battaglio M. Bellomo N. Lancellotta R. Preziosi L. 《Transport in Porous Media》1999,34(1-3):17-27
This paper reports about the derivation of a fully nonlinear model characterized by finite deformations without smallness assumptions. The soil is assumed to be saturated, and no restrictions are introduced on the constitutive laws. Initial boundary value problems are formulated with reference to geotechnical problems, such as consolidation under own weight or sedimentation of solid particles in a quiescent fluid, and back-analyses of field performance of an embankment resting on a soft clay deposit. 相似文献
9.
Wolfgang Rump 《Applied Categorical Structures》2009,17(2):153-174
We give a axiomatic treatment of the absolute in the category of all topological spaces and characterize it as a cover with
respect to the full subcategory of extremally disconnected spaces. As an application, we obtain the strongly projectable hull
of an abelian l-group as a unique lifting of the absolute of its spectrum.
Dedicated to B. V. M. 相似文献
10.
The main purpose of this article is to generalize a recent result about isometries of Lipschitz spaces. Botelho, Fleming and Jamison [2] described surjective linear isometries between vector-valued Lipschitz spaces under certain conditions. In this article, we extend the main result of [2] by removing the quasi-sub-reflexivity condition from Banach spaces. 相似文献