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41.
考虑了Kantorovich-Vertesi有理插值型算子L^*n,s(f,X,x)对L^p[-1,1](1≤p≤∞)空间函数逼近的Jackson型估计。并获得了如下逼近阶:‖L^*n,s(f,X,x)-f(x)‖L^p[-1,1]≤Cp,sw(f,1/n 2)L^p[-1,1] (s>2)。 相似文献
42.
Superstatistics and Tsallis statistics in statistical mechanics are given an interpretation in terms of Bayesian statistical analysis. Subsequently superstatistics is extended by replacing each component of the conditional and marginal densities by Mathai’s pathway model and further both components are replaced by Mathai’s pathway models. This produces a wide class of mathematically and statistically interesting functions for prospective applications in statistical physics. It is pointed out that the final integral is a particular case of a general class of integrals introduced by the authors earlier. Those integrals are also connected to Krätzel integrals in applied analysis, inverse Gaussian densities in stochastic processes, reaction rate integrals in the theory of nuclear astrophysics and Tsallis statistics in nonextensive statistical mechanics. The final results are obtained in terms of Fox’s H-function. Matrix variate analogue of one significant specific case is also pointed out. 相似文献
43.
Arak M. Mathai Hans J. Haubold 《The European Physical Journal B - Condensed Matter and Complex Systems》2018,91(2):39
Based on the results of the diffusion entropy analysis of Super-Kamiokande solar neutrino data, a generalized entropy, introduced earlier by the first author is optimized under various conditions and it is shown that Maxwell–Boltzmann distribution, Raleigh distribution and other distributions can be obtained through such optimization procedures. Some properties of the entropy measure are examined and then Maxwell–Boltzmann and Raleigh densities are extended to multivariate cases. Connections to geometrical probability problems, isotropic random points, and spherically symmetric and elliptically contoured statistical distributions are pointed out. 相似文献
44.
In the theory of thermonuclear reaction rates, analytical evaluation of thermonuclear functions for non-resonant reactions, including cases with cut-off and depletion of the tail of the Maxwell-Boltzmann distribution function were considered in a series of papers by Mathai and Haubold [A.M. Mathai, H.J. Haubold, Modern Problems in Nuclear and Neutrino Astrophysics, Akademie-Verlag, Berlin, 1988]. In the present paper we study more general classes of thermonuclear functions by introducing a pathway parameter α, so that when α→1 the thermonuclear functions in the Maxwell-Boltzmannian case are recovered. We will also give interpretations for the pathway parameter α in the case of cut-off and in terms of moments. Non-extensive statistical mechanics, as developed by Tsallis [C. Tsallis, What should a statistical mechanics satisfy to reflect nature? Physica D 193 (2004) 3-34], provides the physical basis for the generalized thermonuclear functions considered in this paper. 相似文献
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Perfluoromethyl Element Ligands. XXXII. Reactions of the Metal Hydrides π-C5H5(CO)3MH (M = Cr, Mo, W) with Diphosphanes [Ph2?nYnP]2 (Y = I, CN, SiMe3; n = 2, 1, 0) The reactions of π-C5H5(CO)3MH (M = Cr, Mo, W) ( 1a – c ) with the symmetric diphosphanes (Ph2P)2, [Ph(CN)P]2, [(CN)2P]2, and the cyclophosphane (PPh)5, respectively, occur under cleavage of the P? P bond. The reactivity decreases in the series The tendency to form binuclear complexes reflects the basicity of the metallated phosphanes π-C5H5(CO)3MPRR′ and increases in the order P(CN)2 < P(CN)Ph ? P(Ph)H < PPh2. Iodine containing diphosphanes [Ph(I)P? P(I)Ph and P2I4] undergo redox reactions with 1a – c , yielding π-C5H5(CO)3MI and unstable iodo-diphosphanes. No P? P bond cleavage occurs in the reaction of the silyl substituted diphosphanes [Ph(SiMe3)P]2 and [(Me3Si)2P]2 with 1a – c , but P? Si bond fission is the preferred reaction giving π-C5H5(CO)3MSiMe3. 相似文献
49.
Perfluoromethyl Element Ligands. XXX. Reactions of the Metal Hydridesπ-C5H5(CO)3MH (M = Cr, Mo, W) with Organoelement-Element Compounds of the Type R2 EER2 and RE′ ′E ′R (E = P, As; E′ = S, Se; R = CH3, CF3) Cleavage reactions of R2EER2 and RE′E′R, respectively, (E = P, As; E′ = S, Se; R = CH3, CF3) with complexes π-C5H5(CO)3MH (M = Cr, Mo, W) are used (a) to prepare known and novel complex subsituted phosphanes, arsanes, sulfanes, or selanes π-C5H5(CO)3MER2 (I) and π-C5H5(CO)3ME′R (II), respectively, (b) to study the reactivity trends as a function of E, E′, R, and M (see Inhaltsübersicht). The tendency observed for the formation of the binuclear complexes [π-C5H5(CO)2MER2]2 and [π-C5H5(CO)2ME′R]2, respectively, in following reactions of I and II increases in the series W ? Mo ≤ Cr and SeCF3 < As(CF3)2 < SCF3 ≈ P(CF3)2 < SeMe < AsMe2 ?; PMe2 ≈ SMe. 相似文献
50.
Studies on Dialkyl Metal Phosphoric and Phosphinic Acid Derivatives of the Elements Aluminium, Gallium Indium, and Thallium. I. Preparation, Properties, and NMR Spectra of Dialkyl Metal Phosphoric and Phosphinic Acid Derivatives. The trialkyl compounds of Al, Ga, In and Tl react with equimolar quantities of phosphoric or phosphinic acids, HOOPX2 (X = F, Cl, H), HOSP(CH3)2 or HSSP(CH3)2, to form dialkylmetal phosphoric and phosphinic acid derivatives, respectively. The properties and the degree of association of these compounds are listed. The NMR- spectra (1H, 19F and 31P) show that the phosphorus containing groups act as bidentate ligands. 相似文献