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991.
Lj. B. iri Lj. B. iri Lj. B. iri N. T. Nikoli N. T. Nikoli N. T. Nikoli Ume J. S. Ume J. S. Ume J. S. 《Acta Mathematica Hungarica》2006,113(4):257-267
Summary Recently, Pathak [13] has made an extension of the notion of compatibility to weak compatibility, and extended the coincidence
theorem for compatible mappings in Kaneko and Sessa [11] to weakly compatible mappings [13]. In the present paper, we define
a new class of weakly compatible mappings (Definition 4) and prove some common fixed point theorems for these mappings, which
satisfy Condition (2) below. Although our main theorem is formulated for weakly compatible mappings, its corresponding formulation
for commutative mappings is also a new result, thus presenting a generalization of some theorems of Fisher, Das and Naik,
Khan and Kubiaczyk, Reich, Ćirić and Rhoades and Watson. 相似文献
992.
A. A. Sorokin G. K. Ryasny B. A. Komissarova L. N. Fomicheva A. V. Tsvyashchenko S. M. Nikitin 《Hyperfine Interactions》2006,171(1-3):269-275
The perturbed angular correlation (PAC) measurements with the 111In-111Cd nuclear probe embedded into the lattice of the cubic (C15) Laves compound ZrZn2 showed that 111Cd nuclei experienced an axially symmetric electric quadrupole interaction with a frequency ν
Q
= 132.4 MHz at room temperature. The samples were synthesized and doped with the probe at a pressure 8 GPa. The temperature
dependence of ν
Q
was shown to be linear: ν
Q
(T) = 147(1 − 0.033 T) MHz. Since the value of ν
Q
is very close to that known for 111Cd in the lattice of Zn, we have checked if it could be assigned to residual Zn metal in the sample. For the Zn sample melted
and doped with 111In at 8 GPa we have obtained ν
Q
= 117.3 MHz at 300 K and 127 MHz at 80 K – both values considerably lower than that for 111In doped Zn samples prepared at an ambient pressure. These data, and the fact that ν
Q
(T) in Zn is known to follow the T
3/2 law, allow to attribute the ν
Q
value quoted above to 111Cd nuclei at the substitutional sites with tetrahedral symmetry in the Zn sublattice of ZrZn2. 相似文献
993.
区间周期系统的平稳振荡 总被引:5,自引:0,他引:5
本文给出了区间周期系统平稳振荡的概念,建立了区间矩阵稳定性与区间周期系统平稳振荡之间的关系,推广和改进了文[1]的结果. 相似文献
994.
建立了振荡积分渐近性态之奇性指数与(?)-Neumman问题中交换子型边界不变量之间的关系,证明了定理: 与t无关,使得 相似文献
995.
提出了一类新的复合核的二次时频分布,并和几种主要的二次时频分布作了比较研究,实验结果说明的分布具有高的时频分辨力和强的抑制交叉干扰能力。 相似文献
996.
997.
We study time-periodic Oseen flows past a rotating body in ℝ3 proving weighted a priori estimates in Lq-spaces using Muckenhoupt weights. After a time-dependent change of coordinates the problem is reduced to a stationary Oseen equation with the additional terms (ω ∧ x) ⋅ ∇ u and −ω ∧ u in the equation of momentum where ω denotes the angular velocity. Due to the asymmetry of Oseen flow and to describe its wake we use anisotropic Muckenhoupt weights, a weighted theory of Littlewood–Paley decomposition and of maximal operators as well as one-sided univariate weights, one-sided maximal operators and a new version of Jones' factorization theorem. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
998.
Direct reversed-phase high-performance liquid chromatographic methods were developed for the separation of enantiomers of
eighteen unnatural β-amino acids, including several β-3-homo-amino acids. The direct separations of the underivatized analytes were performed on chiral stationary phases containing
macrocyclic glycopeptide antibiotics such as teicoplanin (Chirobiotic T and T2), teicoplanin aglycone (Chirobiotic TAG), vancomycin
(Chirobiotic V and V2), and ristocetin A (Chirobiotic R) as chiral selectors. The effects of the organic modifier, mobile
phase composition and pH on the separations were investigated. A comparison of the separation performances of the macrocyclic
glycopeptide stationary phases revealed that the Chirobiotic T2 column exhibited better selectivity than the Chirobiotic T
column for the separation of β-3-homo-amino acid enantiomers; vancomycin or ristocetin A exhibited lower selectivity. The elution sequence was determined
in some cases: the S enantiomers eluted before the R enantiomers, with the exception of the Chirobiotic R column, where the elution sequence R < S was observed. 相似文献
999.
Cu-Cr alloys, irradiated with a low-energy, high-current electron beam, are analyzed by high-resolution secondary ion mass spectrometry. Mass spectra and images of Cu+ and Cr+ surface distributions finely reveal the regions enriched in Cu and Cr. For electron beam energies above a threshold value, the formation of a non-equilibrium Cu1−xCrx solid solution, extending over sub-micrometer areas is highlighted for the first time. A discussion of the process leading to Cu1−xCrx formation is given. 相似文献
1000.
潘君 《河南师范大学学报(自然科学版)》1995,23(4):5-8
本文研究一维可压缩粘性流体解的大时间渐近性态,在任意大的外力f(x)的作用下,证明了在初始小扰动下流动将渐近趋向于稳态流。 相似文献