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121.
Wertheim’s integral equation theory for associating fluids is reformulated for the study of the connectedness properties of
associating hard spheres with four bonding sites. The association interaction is described as a square-well saturable attraction
between these sites. The connectedness version of the Ornstein-Zernike (OZ) integral equation is supplemented by the PY-like
closure relation and solved analytically within an ideal network approximation in which the network is represented as resulting
from the crossing of ideal polymer chains. The pair connectedness functions and the mean cluster size are calculated and discussed.
The condition for the percolation transition and the analytical form of the percolation threshold are derived. The connection
of the percolation with the gas-liquid phase transition is discussed. 相似文献
122.
Tonghai Yang 《Proceedings of the American Mathematical Society》1998,126(4):999-1004
In this note, we apply the method of Rodriguez Villegas and Yang (1996) to construct a family of infinite many theta series over the Hilbert-Blumenthal modular surfaces with a common zero. We also relate the non-vanishing of the central L-values of certain Hecke characters of non-biquadratic CM number fields of degree 4 to the nonvanishing of theta functions at CM points in the Hilbert-Blumenthal modular surfaces.
123.
Pedro Jiménez Guerra Miguel Angel Melguizo María J. Mu?oz-Bouzo 《Set-Valued Analysis》2007,15(1):47-59
The paper deals with the properties of a conic set-valued function defined on the set of all ideal points of vector programming
problems. The results here about the continuity and derivability of this conic set-valued map, can be used to get information
about the sensitivity of the problem and the stability of the order associated to every ideal point. Furthermore, it is proved
that certain contingent cones are determined by the ideal conic set-valued map.
相似文献
124.
Jingbo Xia 《Journal of Functional Analysis》2005,228(2):369-393
A norm ideal C is said to satisfy condition (QK) if there exist constants 0<t<1 and 0<B<∞, such that ∥X[k]∥C?Bkt∥X∥C for every finite-rank operator X and every k∈N, where X[k] denotes the direct sum of k copies of X. Let μ be a regular Borel measure whose support is contained in a unit cube Q in Rn and let Kj be the singular integral operator on L2(Rn,μ) with the kernel function (xj-yj)/|x-y|2, 1?j?n. Let {Qw:w∈W} be the usual dyadic decomposition of Q, i.e., {Qw:|w|=?} is the dyadic partition of Q by cubes of the size 2-?×?×2-?. We show that if C satisfies (QK) and if ∥∑w∈W2|w|μ(Qw)ξw⊗ξw∥C′<∞, where C′ is the dual of C(0) and {ξw:w∈W} is any orthonormal set, then K1,…,Kn∈C′. This is a very general obstruction result for the problem of simultaneous diagonalization of commuting tuples of self-adjoint operators modulo C. 相似文献
125.
Pierre Matet 《Mathematical Logic Quarterly》2003,49(6):615-628
Given a regular infinite cardinal κ and a cardinal λ > κ, we study fine ideals H on Pκ(λ) that satisfy the square brackets partition relation , where μ is a cardinal ≥2. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
126.
127.
设Q为有理数域,令φ为由奇素数p生成的有理数域Q的p-adic赋值,R为与其相对应的赋值环,(p)为R的极大理想(素理想).本文用扩张平移的方法讨论了lm)(μ∈R)中的分解问题,并完全解决了该问题.素理想(p)在Q的lm次根扩张Q(μ1 相似文献
128.
The assumption that the same universal scale of time applies for different physical laws depends uponthe hypothesis that there is a unique universal scale of time in the universe. Intrinsic to that hypothesis is the assumption that if extraneous factors that affect physical clocks and processes that run on different physical principles could be removed, all clocks are synchronizable with one another. The consequences of that hypothesis not being true are considered. It was found thatclock asynchrony implies that: (1) a mass variation theory is probable; (2) there is a need for multiple clocks; and (3) t in the equations of physics is referring to clocks rather than time such that the properties of time are reduced to its direction (as characterized by thermodynamics and cosmology). 相似文献
129.
G是群,R是G-分次环.本文将有限群G分次环R与G的smashproductR#G ̄*的理想交性质推广到无限群的情形.证明了:G是无限群,R是非奇异G-分次环.R与G的广义smashproductR#G ̄*有理想交性质的充要条件,对任意0≠a_e∈R_e. 相似文献
130.
整表代数是群代数的推广,它的理想是群代数码的推广.本文给出了整表代数的单边理想是自正交理想的必要充分条件. 相似文献