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991.
The assumptions underlying the extraction of micellar aggregation numbers by means of applying the mass action law to the concentration dependence of13C Nuclear Magnetic Resonance (NMR) shift data are discussed. Such data are presented for sodium dodecylsulfate and it is shown that the extracted aggregation numbers are far too small. It is argued that this is in part due to a failure of the mass action law to describe the micellization process but also due to covariance in the parameters of the mass action law. We also suggest a way to analyse13C shifts from surfactant systems that is void of artefacts due to changes in volume magnetic susceptibilities and other unwanted artefacts. Finally, we point out that by combining13C shifts with the fraction of micellized surfactant (as measured by for instance self diffusion coefficients) it should be possible to monitor changes in micellar shapes as the conditions are changed. 相似文献
992.
S. Raghavan 《Proceedings Mathematical Sciences》1984,93(2-3):147-160
Recently, Bombieri and Vaaler obtained an interesting adelic formulation of the first and the second theorems of Minkowski
in the Geometry of Numbers and derived an effective formulation of the well-known “Siegel’s lemma” on the size of integral
solutions of linear equations. In a similar context involving linearinequalities, this paper is concerned with an analogue of a theorem of Khintchine on integral solutions for inequalities arising from
systems of linear forms and also with an analogue of a Kronecker-type theorem with regard to euclidean frames of integral
vectors. The proof of the former theorem invokes Bombieri-Vaaler’s adelic formulation of Minkowski’s theorem. 相似文献
993.
J. Scott Carter Masahico Saito 《Proceedings of the American Mathematical Society》1997,125(2):617-623
We present a new formula relating the normal Euler numbers of embedded surfaces in -space and the number of triple points on their projections into -space. This formula generalizes Banchoff's formula between normal Euler numbers and branch points on the projections.
994.
Let {S
n}
n0 be a random walk on the line. We give criteria for the existence of a nonrandom sequence n
i for which
respectively
We thereby obtain conditions for to be a strong limit point of {S
n} or {S
n
/n}. The first of these properties is shown to be equivalent to
for some sequence a
i , where T(a) is the exit time from the interval [–a,a]. We also obtain a general equivalence between
and
for an increasing function fand suitable sequences n
i and a
i. These sorts of properties are of interest in sequential analysis. Known conditions for
and
(divergence through the whole sequence n) are also simplified. 相似文献
995.
André Adler Andrew Rosalsky Andrej I. Volodin 《Journal of Theoretical Probability》1997,10(3):605-623
For a sequence of constants {a
n,n1}, an array of rowwise independent and stochastically dominated random elements { V
nj, j1, n1} in a real separable Rademacher type p (1p2) Banach space, and a sequence of positive integer-valued random variables {T
n, n1}, a general weak law of large numbers of the form
is established where {c
nj, j1, n1},
n , b
n are suitable sequences. Some related results are also presented. No assumption is made concerning the existence of expected values or absolute moments of the {V
nj, j1, n1}. Illustrative examples include one wherein the strong law of large numbers fails. 相似文献
996.
Kenneth B. Stolarsky 《Proceedings of the American Mathematical Society》1997,125(1):35-39
The so-called ``-identities' play a major role in classical combinatorics. Most of them can be viewed as arising somehow in the context of hypergeometric series. Here we present a ``sum of squares' identity involving -analogues of the triangular numbers that, by contrast, arises in the context of distance geometry.
997.
Let be a finite set of rational primes. We denote the maximal Galois extension of in which all totally decompose by . We also denote the fixed field in of elements in the absolute Galois group of by . We denote the ring of integers of a given algebraic extension of by . We also denote the set of all valuations of (resp., which lie over ) by (resp., ). If , then denotes the ring of integers of a Henselization of with respect to . We prove that for almost all , the field satisfies the following local global principle: Let be an affine absolutely irreducible variety defined over . Suppose that for each and for each . Then . We also prove two approximation theorems for .
998.
We show that the problem of representing every odd positive integer as the sum of a squarefree number and a power of 2, is strongly related to the problem of showing that p2 divides 2{p-1}-1 for few primes p. 相似文献
999.
It is well-known that the Euler polynomials E2n(x) with n 0 can be expressed as a polynomial Hn(x(x – 1)) of x(x – 1). We extend Hn(u) to formal power series for n < 0 and prove several properties of the coefficients appearing in these polynomials or series, which generalize some recent results, independently obtained by Hammersley [7] and Horadam [8], and answer a question of Kreweras [9]. We also deduce several continued fraction expansions for the generating function of Euler polynomials, some of these formulae had been published by Stieltjes [14] and by Rogers [12] without proof. These formulae generalize our earlier results concerning Genocchi numbers, Euler numbers and Springer numbers [5, 4]. 相似文献
1000.
《Expositiones Mathematicae》2022,40(4):1244-1260
We introduce and study Hodge–de Rham numbers for compact almost complex 4-manifolds, generalizing the Hodge numbers of a complex surface. The main properties of these numbers in the case of complex surfaces are extended to this more general setting, and it is shown that all Hodge–de Rham numbers for compact almost complex 4-manifolds are determined by the topology, except for one (the irregularity). Finally, these numbers are shown to prohibit the existence of complex structures on certain manifolds, without reference to the classification of surfaces. 相似文献