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111.
As is usual in prime number theory, write It is well known that when q is close to x the averagevalue of is about xlog q,and recently Friedlander and Goldston have shown that if then the first moment of V(x,q)-U(x,q)is small. In this memoir it is shown that the same is true forall moments. 2000 Mathematics Subject Classification: 11N13. 相似文献
112.
Photoionization, X-ray emission and UV excitation energies are calculated for SiO2 by the SCF Xα method and the transition-state procedure. In all cases agreement between calculation and experiment is good. The SiO4?4 cluster is found to be adequate for describing localized excitations in quartz. The valence orbitals of this cluster are found to be naturally separable into three sets (1) 3t2 and 4a1; O 2s, nonbonding: (2) 5a1 and 4t2; Si 3s, 3p and O 2p, sigma bonding: (3) 1e, 5t2, 1t1; O 2p nonbonding. The participation of Si 3d-type functions in the high-energy O 2p nonbonding orbitals is found to be very small. 相似文献
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Let π = (a1, a2, …, an), ? = (b1, b2, …, bn) be two permutations of . A rise of π is pair ai, ai+1 with ai < ai+1; a fall is a pair ai, ai+1 with ai > ai+1. Thus, for i = 1, 2, …, n ? 1, the two pairs ai, ai+1; bi, bi+1 are either both rises, both falls, the first a rise and the second a fall or the first a fall and the second a rise. These possibilities are denoted by RR, FF, RF, FR. The paper is concerned with the enumeration of pairs π, p with a given number of RR, FF, RF, FR. In particular if ωn denotes the number of pairs with RR forbidden, it is proved that , . More precisely if ω(n, k) denotes the number of pairs π, p with exactly k occurences of RR(or FF, RF, FR) then . 相似文献
115.
The activation of the apo-enzyme of calf-intestinal alkaline phosphatase by zinc in the presence and absence of magnesium 4 x 10(-4)M) is applied to the determination of 6-65 ng and 65-650 ng of zinc, respectively. The activation of the apo-enzyme by calcium in the presence of 1.4 x 10(-7)M zinc is used to determine 1-4 mug of calcium. The mechanism of the re-activation effects is discussed. 相似文献
116.
The paper is concerned with the enumeration of pairs of sequences with given specification according to rises, falls and levels. Thus there are nine possibilities RR, ..., LL. Generating functions in the general case are very complicated. However in a number of special cases simple explicit results are obtained.Supported in part by NSF grant GP-37924X. 相似文献
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Swiderski K McLean A Gordon CM Vaughan DH 《Chemical communications (Cambridge, England)》2004,(19):2178-2179
Systematic variation in the bimolecular rate constant, k(q), for the reaction of singlet oxygen and 1,4-dimethylnaphthalene has led to estimates of the Hildebrand solubility parameter, cohesive pressures and internal energies of vaporisation of some room temperature ionic liquids. 相似文献