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81.
Zbigniew J. Jurek 《Journal of multivariate analysis》1983,13(4):578-604
Let
= {Ut: t > 0} be a strongly continuous one-parameter group of operators on a Banach space X and Q be any subset of a set
(X) of all probability measures on X. By
(Q;
) we denote the class of all limit measures of {Utn(μ1 * μ2*…*μn)*δxn}, where {μn}Q, {xn}X and measures Utnμj (j=1, 2,…, n; N=1, 2,…) form an infinitesimal triangular array. We define classes Lm(
) as follows: L0(
)=
(
(X);
), Lm(
)=
(Lm−1(
);
) for m=1, 2,… and L∞(
)=m=0∞Lm(
). These classes are analogous to those defined earlier by Urbanik on the real line. Probability distributions from Lm(
), m=0, 1, 2,…, ∞, are described in terms of their characteristic functionals and their generalized Poisson exponents and Gaussian covariance operators. 相似文献
82.
We show that if u is a plurisubharmonic function defined on an open subset of 2 then the Monge-Ampère measure (ddcu)2 can be well defined if and only if u belongs to the Sobolev space W1,2loc().Partially supported by KBN Grant #2 P03A 028 19 相似文献
83.
Let K be the field of real or complex numbers. Let (X K2n,) be a symplectic vector space and take 0 < k < n,N =. Let L1,...,LN X be 2k-dimensionallinear subspaces which are in a sufficiently general position.It is shown that if F : X X is a linear automorphism whichpreserves the form k on all subspaces L1,...,LN, then F is ank-symplectomorphism (that is, F* = k, where ). In particular, if K = R and k is odd then F mustbe a symplectomorphism. The unitary version of this theoremis proved as well. It is also observed that the set Al,2r ofall l-dimensional linear subspaces on which the form has rank 2r is linear in the Grassmannian G(l,2n), that is, there isa linear subspace L such that Al,2r = L G(l, 2n). In particular,the set Al,2r can be computed effectively. Finally, the notionof symplectic volume is introduced and it is proved that itis another strong invariant. 相似文献
84.
Stachurski ZH 《Physical review letters》2003,90(15):155502
It is proposed that two ideal amorphous structures, type I and type II, based on maximally random jammed packing of spheres of equal size, form a distinct class of ideal amorphous solids. The ideal amorphous structures contain wide variations in local density, limited by the condition of solidity. Four distinct characteristics, based on statistical geometry and topology, are shown to define this class. Voronoi tessellations carried out on simulated cells of random packed spheres and amorphous polymers give a broad distribution of individual volumes, skewed, with a tail at the high volume end. 相似文献
85.
86.
Howarth DF Weil JA Zimpel Z 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2003,161(2):215-221
A new lineshape function is derived from the Tsallis distribution to describe electron paramagnetic resonance (EPR) spectra, and possibly nuclear magnetic resonance (NMR) spectra as well. This lineshape generalizes the Gaussian and Lorentzian lineshapes that are widely used in simulations. The main features of this lineshape function are presented: the normalization, moments, and first derivative. A number of experimental EPR spectra are compared with the results of simulations employing the new lineshape function. The results show that the new lineshape often provides a better approximation of the experimental spectrum. It is also shown that the new parameter of the lineshape function can be used to quantify the intermolecular spin-spin interactions. 相似文献
87.
Addition of dipropylamine to multiacrylate and its model compound catalyzed by lithium dipropylamide
The nucleophilic addition reaction of dipropylamine to vinyl groups of multiacrylate - poly(2-acryloyloxyethyl methacrylate)
and to 2-butyrylethyl acrylate as model compound has been investigated. Based on the results obtained, it has been shown that
the addition reaction rate of dipropylamine to multiacrylate and 2-butyrylethyl acrylate is proportional to [CH2=CH-] and to [(C3H7)2NLi] with the ratio [(C3H7)2NH]o/[(C3H7)2NLi]o = 20. Second-order addition reaction rate constants and activation energies for the systems under investigation have been
determined.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
88.
89.
Pacholska E Latos-Grazyński L Ciunik Z 《Angewandte Chemie (International ed. in English)》2001,40(23):4466-4469
90.
Zbigniew Jelonek 《Proceedings of the American Mathematical Society》2003,131(5):1361-1367
Let be a polynomial of degree . Assume that the set there is a sequence s.t. and is finite. We prove that the set of generalized critical values of (hence in particular the set of bifurcation points of ) has at most points. Moreover, We also compute the set effectively.