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41.
On the harmonic Bergman space of the half-space, we give characterizations for an arbitrary positive Toeplitz operator to
be a Schatten (or Schatten-Herz) class operator in terms of averaging functions and Berezin transforms. Examples are provided
to show that various results are sharp.
This research was supported by KOSEF(R01-2003-000-10243-0). 相似文献
42.
In this paper, the structure of cubic CaTiO3 (001) surfaces with CaO and TiO2 terminations has been studied from density functional calculations. It has been found that the Ca atom has the largest relaxation for both kinds of terminations, and the rumpling of the CaO-terminated surface is much larger than that of TiO2-terminated surface. Also we have found that the metal atom relaxes much more prominently than the O atom does in each layer. The CaO-terminated surface is slightly more energetically favourahle than the TiO2-terminated surface from the analysis of the calculated surface energy. 相似文献
43.
Nusselt number correlations for heat transfer to small spheres in thermal plasma flows 总被引:1,自引:0,他引:1
Seven different equations predicting heat transfer rates to small spheres in plasma flows are examined considering argon and nitrogan as plasma gases from 300 to 21,000 K at 1 atm. For argon there is a general consensus up to 9000 K, beyond which wide deviations in behavior occur. For nitrogen, the seven correlations are in good agreement up to 4000 K, but show substantial deviations beyond this value. Comparisons with the sparsely available experimental data are made for argon from 300 to 17,000 K and for nitrogen up to 5500 K. Disagreement between the various correlations and experiment can exceed one order of magnitude. 相似文献
44.
45.
Young Wook Kim Seong-Deog Yang 《Proceedings of the American Mathematical Society》2006,134(11):3379-3390
We prove the existence of an infinite family of complete spacelike maximal surfaces with singularities in Lorentz-Minkowski three-space and study their properties. These surfaces are distinguished by their number of handles and have two elliptic catenoidal ends.
46.
Mary Cheung Alex B. Young Alex G. Harrison 《Journal of the American Society for Mass Spectrometry》1994,5(6):553-557
O? and OH? react with fatty acid methyl esters (FAMES) under chemical ionization conditions both as Bronsted bases to form [M - H]? and as nucleophiles to form the carboxylate ion RCOO?. O? shows a much greater tendency to react as a nucleophile than does OH?. The [M - H]? ions fragment by elimination of CH3OH, with unsaturation in certain positions in the fatty acid hydrocarbon chain promoting this elimination for unknown reasons. The reaction of O? and OH? with triacylglycerols leads to [M - H]?, characteristic of the molecular mass, and to carboxylate ions characteristic of the fatty acid(s) present in the lipid. The presence of the three ester functions in the lipids greatly enhances the formation of carboxylate ions compared to the FAMES. 相似文献
47.
Ranked-set sampling is useful when measurements are destructive or costly to obtain but ranking of the observations is relatively easy. The Wilcoxon signed rank test statistic based on the ranked-set sample is considered. We compared the asymptotic relative efficiencies of the RSS Wilcoxon signed rank test statistic with respect to the SRS Wilcoxon signed rank test statistic and the RSS sign test statistic. Throughout the ARE’s, the proposed test statistic is superior to the SRS Wilcoxon signed rank test statistic and the RSS sign test statistic. 相似文献
48.
纬向对称准地转流的非线性稳定性定理 总被引:4,自引:0,他引:4
建立了周期域上准地转流在一般的边界条件下对应于Arnold第二定理的非线性稳定性定理。将扰动能量与扰动拟能的上界用初始扰动场的显示表示出来,从而建立了Liapunov意义下的非线性稳定性定理。 相似文献
49.
50.
The reference [4] proved the consistency of S1 and S2 among Lewis' five strict implication systems in the modal logic by using the method of the Boolean-valued model. But, in this method, the consistency of S3, S4 and S5 in Lewis' five strict implication systems is not decided. This paper makes use of the properties: (1) the equivalence of the modal systems S3 and P3, S4 and P4; (2) the modal systems P3 and P4 all contained the modal axiom T(□p → p); (3) the modal axiom T is correspondence to the reflexive property in VB. Hence, the paper proves: (a) ‖As31‖ = 1; (b) ‖AS41‖ = 1; (c) ‖AS5l‖ = 1 in the model (where B is a complete Boolean algebra, R is reflexive property in VB). Therefore, the paper finally proves that the Boolean-valued model VB of the ZFC axiom system in set theory is also a Boolean-valued model of Lewis' the strict implication system S3, S4 and S5. 相似文献