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31.
32.
33.
The existence of a Nash equilibrium in the undiscounted repeated two-person game of incomplete information on one side is
established. The proof depends on a new topological result resembling in some respect the Borsuk-Ulam theorem. 相似文献
34.
We generalize several results on bounded analytic interpolation of Fitzgerald and Horn, which work by majorization by positive
definite kernels, to the cases of several complex variables and operator-valued interpolation. Using a lemma of Kolmogorov,
we complement a simplification due to Szafraniec in the proofs of the theorems.
Received: November 21, 2006. Accepted: August 03, 2007. 相似文献
35.
A. Maignan Ch. Simon V. Caignaert B. Raveau 《Zeitschrift für Physik B Condensed Matter》1995,99(1):305-310
The exploration of the magnetic and transport properties of four series of manganese perovskites, Pr0.7Ca0.34−xAxMnO3−δ (A=Sr, Ba), Pr0.7−xLaxCa0.3 MnO3−δ and Pr0.66Ca0.34−x
SrxMnO3−δ has allowed four phases with colossal magnetoresistive (CMR) properties to be isolated: Pr0.7Ca0.25Sr0.025MnO3−δ and Pr0.66Ca0.26Sr0.08MnO3−δ that exhibit a variation of resistance of 2.5. 107% and 109% at μ0 H=5 T for T=88 K and 50 K respectively, Pr0.58La0.12Ca0.3 MnO3−δ that exhibits a variation of 6.106% for μ0 H=5 T at T=80 K and Pr0.7Ba0.025Ca0.275MnO3−δ for which a resistance variation of 5.109%, at T=50 K, for μ0 H=5 T is evidenced. for each compound of this series except the barium phase, one observes that the temperature Tmax, which corresponds to the resistance maximum on the R(T) curves in zero magnetic field, increases dramatically as the mean
size of the interpolated cations increases, and that the CMR effect correlatively decreases dramatically. The comparison of
the two series Pr0.7Ca0.3−xSrxMnO3−δ and Pr0.66Ca0.34−xSrxMnO3−δ shows also the crucial role of the hole carrier density: for a same mean ionic radius of the interpolated cation Tmax is decreased of about 50 K by introducing 0.034 hole per Mn mole. 相似文献
36.
37.
Simon French 《The Journal of the Operational Research Society》1994,45(11):1341-1341
38.
Simon Thomas 《Archive for Mathematical Logic》1998,37(7):483-493
We study the relationship between the cofinality of the infinite symmetric group and the cardinal invariants and . In particular, we prove the following two results.
Theorem 0.1
It is consistent with
ZFC
that there exists a simple
$P_{\omega_{1}}$
-point and that
$c(Sym(\omega)) = \omega_{2} = 2^{\omega}$
.
Theorem 0.2
If there exist both a simple
$P_{\omega_{1}}$
-point and a
$P_{\omega_{2}}$
-point, then
$c(Sym(\omega)) = \omega_{1}$
.
Received: 7 March 1996 相似文献
39.
The exciton-exciton interaction is investigated for spatially indirect excitons in coupled quantum wells. The Hartree-Fock and Heitler-London approaches are improved by a full two-exciton calculation including the van der Waals effect. Using these potentials for the singlet and triplet channel, the two-body scattering matrix is calculated and employed to derive a modified relation between exciton density and blue shift. Such a relation is of central importance for gauging exciton densities on the way toward Bose condensation. 相似文献
40.
T. Rajagopalan J.A. Lubguban S. Gangopadhyay J. Sun S.L. Simon R. Butler 《Applied Surface Science》2006,252(18):6323-6331
Hexamethyldisilazane (HMDS) vapor treatment of plasma-damaged nanoporous organosilicate thin films has been studied as a function of treatment temperature in this work. Although, the HMDS vapor treatment facilitated incorporation of methyl (CH3) groups subsequent to the removal of free hydroxyl (OH) groups in the damaged films at treatment temperature as low as 55 °C, the bonded OH groups were not removed. More significantly, detailed analysis of the results reveals that HMDS vapor modified only the surface of the plasma-damaged samples and not the entire film as expected. This is attributed to the formation of a thin solid layer on the surface, which effectively prevents penetration of HMDS vapors into the bulk. The Fourier transform-infrared (FT-IR) absorption and dielectric constant measurements confirm that the vapor treatment assists only partial curing of the plasma-damaged films. Alternative processes of curing the films with HMDS dissolved in supercritical carbon dioxide (SCCO2) as a medium of reaction in static and pulsed modes were also attempted and the results are presented in this paper. 相似文献