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991.
992.
A theorem on the presentability of a multiple integral as a linear form in 1, ζ(3), ζ(5),..., ζ(2k − 1) over ℚ is proved. This theorem refines the results recently obtained by D. Vasiliev, V. Zudilin, and S. Zlobin.
__________
Translated from Fundamentalnaya i Prikladnaya Matematika, Vol. 11, No. 6, pp. 143–178, 2005. 相似文献
993.
We prove estimates in weighted Hölder norms for a solution to the model linear problem related with the one-phase Stefan problem with a small multiplier ε at time derivative in the heat equation. These estimates are uniform with respect to parameter ε and are significant in justification of passage to the limit in the one-phase Stefan problem as the specific heat tends to zero. Bibliography: 8 titles. 相似文献
994.
O. V. Il’in 《Journal of Mathematical Sciences》2007,141(1):1041-1047
We describe W-geometry of two-dimensional Toda systems associated with the Lie algebra C
n
.
__________
Translated from Fundamental’naya i Prikladnaya Matematika (Fundamental and Applied Mathematics), Vol. 11, No. 1, Geometry,
2005. 相似文献
995.
In this article, composite nanofibers of poly(ε-caprolactone) (PCL) with iron–platinum (FePt) nanoparticles were successfully fabricated via coaxial electrospinning. The structure and morphology of FePt/PCL composite nanofibers were observed using transmission electron microscope and scanning electron microscope, respectively. The magnetic behavior of FePt/PCL composite nanofibers was investigated by alternating gradient magnetometer at room temperature. 相似文献
996.
Z.J. Liu H.H. Long W.C. Ye X.X. Zou Z.L. Qin E.P. Li J.S. Chen 《Journal of magnetism and magnetic materials》2006
In this paper, specific issues related to high-density perpendicular magnetic recording processes, such as transition noise properties and cross-track correlation lengths, were investigated with the help of micromagnetic analysis. The effects of media parameters were taken into consideration, including intergranular exchange coupling, and exchange distribution, irregular grain shapes, magnetization saturation distribution, and anisotropy distribution. The micromagnetic simulation results showed that the effect of anisotropy distribution on transition noise is more significant than magnetization saturation distribution, and it is crucial to reduce this effect to achieve a high signal-to-noise ratio. Additionally, a new method to further estimate the partial erasure threshold was proposed to approximate the partial erasure effects, and the relation between the microtrack jitter and total track jitter was investigated. 相似文献
997.
O. V. Okatova N. N. Ul’yanova E. G. Bulycheva L. B. Elshina A. L. Rusanov P. N. Lavrenko 《Polymer Science Series A》2007,49(6):716-721
The molecular properties of a number of new poly(naphthylimides) derived from naphthalene-1,4,5,8-tetracarboxylic dianhydride and bis(naphthalic anhydrides) have been studied. On the basis of hydrodynamic studies of the polymers at various stages of their thermal degradation in 96% H2SO4 and thermogravimetric measurements, the hydrolytic stability and thermooxidative resistance of the polymers have been compared. A correlation between the experimental data and the chemical structure of molecular chains has been established. 相似文献
998.
The 8-mol percentage Y2O3-stabilized Porous Zirconia was prepared using sol–gel method. Zirconium oxalate gel was prepared by the addition of appropriate
amount of oxalic acid solution into the 1 M aqueous solution of zirconium-oxy chloride. A cubic phase zirconia powder was
obtained by calcination and milling of the zirconium oxalate gel. Crystallization temperature was found about 450 °C from
the Differential thermal analysis. The phase analysis by X-ray diffraction shows the presence of cubic phase. Pellets sintered
at 1,350 °C were highly porous, and the electrical conductivity was found with lower value due to the porosity, and the hardness
was about 8.0 GPa.
Paper presented at the Third International Conference on Ionic Devices (ICID 2006), Chennai, Tamilnadu, India, Dec. 7–9, 2006. 相似文献
999.
We prove that there is a first-order sentence ϕ such that the group of all computable automorphisms of the ordering of the
rational numbers is its only model among the groups that are embeddable in the group of all computable permutations.
Supported by a Scheme 2 grant from the London Mathematical Society.
__________
Translated from Algebra i Logika, Vol. 46, No. 5, pp. 649–662, September–October, 2007. 相似文献
1000.
In this paper we present several results about local MV-algebras, extending existing results given for MV-chains. The role
of local MV-algebras in sheaf representation and weak boolean product is stressed and the relationship of local MV-algebras
with varieties of MV-algebras is analyzed.
Presented by S. Pulmannova.
Received November 11, 2005; accepted in final form December 20, 2005. 相似文献