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61.
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M. S. Yunusov E. M. Tsyrlina E. D. Khairitdinova L. V. Spirikhin A. Yu. Kovalevsky M. Yu. Antipin 《Russian Chemical Bulletin》2000,49(9):1629-1633
A new alkaloid, anhydrolycaconitine (C36H46N2O9), was isolated from roots ofAconitum septentrionale K. Based on the results of1H and13C NMR and IR spectroscopy and mass spectrometry of the alkaloid and the product of its alkaline hydrolysis and on the data
of X-ray diffraction analysis of the hydrolysis product, the structure of 1α, 6β, 14α, 16β-tetramethoxy-7-oxo-18-succinylanthranoyloxy-17-(7→8)abeo-aconane was assigned to anhydrolycaconitine.
Published inIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1640–1644, September, 2000. 相似文献
63.
64.
利用k次单位根及其正交性得到级数∑∞n=0xkn+l/(kn+l)!的和函数.它与利用微分方程理论来求级数的和有很大区别.作为应用,得到了一些特殊级数的和. 相似文献
65.
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In this work we obtain an asymptotic estimate for the expected number of maxima of the random algebraic polynomial
, where a
j (j=0, 1,...,n–1) are independent, normally distributed random variables with mean and variance one. It is shown that for nonzero , the expected number of maxima is asymptotic to
log n, when n is large. 相似文献
67.
对一个图G,设μ(G,x)表示它的匹配多项式,M(G,x)表示μ(G,x)的最大实数根.令Г_1={G|M(G,x)<2}和Г2={G|M(G,x)≤2}.给出了Г_i(i=1,2)中的两个图G和H匹配等价的充要条件. 相似文献
68.
J. V. Leyendekkers A. G. Shannon 《International Journal of Mathematical Education in Science & Technology》2013,44(2):303-306
The modular ring ?6 defines integers via (6r i + (i ? 3)) where i is the class and r i the row when tabulated in an array. Since only Classes 26 and 46 contain odd primes, this modular ring is ideally suited to the analysis of twin primes. The calculations are facilitated by the use of the right-end digit (RED) technique. 相似文献
69.
In the study of the Sparre Andersen risk model with phase‐type (n) inter‐claim times (PH (n) risk model), the distinct roots of the Lundberg fundamental equation in the right half of the complex plane and the linear independence of the eigenvectors related to the Lundberg matrix Lδ(s) play important roles. In this paper, we study the case where the Lundberg fundamental equation has multiple roots or the corresponding eigenvectors are linearly dependent in the PH (n) risk model. We show that the multiple roots of the Lundberg fundamental equation det[Lδ(s)] = 0 can be approximated by the distinct roots of the generalized Lundberg equation introduced in this paper and that the linearly dependent eigenvectors can be approximated by the corresponding linearly independent ones as well. Using this result we derive the expressions for the Gerber–Shiu penalty function. Two special cases of the generalized Erlang(n) risk model and a Coxian(3) risk model are discussed in detail, which illustrate the applicability of main results. Finally, we consider the PH(2) risk model and conclude that the roots of the Lundberg fundamental equation in the right half of the complex plane are distinct and that the corresponding eigenvectors are linearly independent. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
70.
The asymptotic estimate for the expected number of real zeros of a random algebraic polynomial
is known. The identical random coefficients aj(ω) are normally distributed defined on a probability space
, ω ∈Ω. The estimate for the expected number of zeros of the derivative of the above polynomial with respect to x is also known, which gives the expected number of maxima and minima of Qn(x, ω). In this paper we provide the asymptotic value for the expected number of zeros of the integration of Qn(x,ω) with respect to x. We give the geometric interpretation of our results and discuss the difficulties which arise when we consider a similar
problem for the case of
. 相似文献