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91.
Elói Medina Galego 《Monatshefte für Mathematik》2002,136(2):87-97
We study the relation of to the subspaces and quotients of Banach spaces of continuous vector-valued functions , where K is an arbitrary dispersed compact set. More precisely, we prove that every infinite dimensional closed subspace of totally incomparable to X contains a copy of complemented in . This is a natural continuation of results of Cembranos-Freniche and Lotz-Peck-Porta. We also improve our result when K is homeomorphic to an interval of ordinals. Next we show that complemented subspaces (resp., quotients) of which contain no copy of are isomorphic to complemented subspaces (resp., quotients) of some finite sum of X. As a consequence, we prove that every infinite dimensional quotient of which is quotient incomparable to X, contains a complemented copy of . Finally we present some more geometric properties of spaces.
Received 8 November 2000; in revised form 7 December 2001 相似文献
92.
Olga Ordeig Craig E Banks Trevor J Davies F Javier del Campo Francesc Xavier Mu?oz Richard G Compton 《Analytical sciences》2006,22(5):679-683
Gold ultra-microelectrode arrays are used to explore the electrochemical oxidation of hydroxide ions and are shown to be analytical useful. Two types of ultra-microelectrode arrays are used; the first consist of 256 individual electrodes of 5 microm in radius, 170 of which are electrochemically active in a cubic arrangement which are separated from their nearest neighbour by a distance of 100 microm. The second array compromises 2597 electrodes of 2.5 microm in radius and of which 1550 of which are electrochemically active in a hexagonal arrangement separated by the nearest neighbour by 55 microm. Well defined voltammetric waves are found with peak currents proportional to the concentration of hydroxide ions in the range 50 microM to 1 mM. Detection limits of 20 microM using the 170 ultra-microelectrode and 10 microM with the 1550 ultra-microelectrode array are shown to be possible but with a higher sensitivity of 4 mA M(-1) observed using the 1550 ultra-microelectrode array compared to 1.2 mA M(-1) with the 170 ultra-microelectrode array. 相似文献
93.
Ivan Gutman Sabina Gojak Niko Radulovi? Boris Furtula 《Monatshefte für Chemie / Chemical Monthly》2006,46(2):277-284
In a recent work it was demonstrated that in linear hexagonal chains the distribution of π-electrons into rings (as computed
by means of the Randić–Balaban method) is uniform, irrespective of the nature of the terminal fragments. We now establish that an analogous, yet somewhat
more complex, uniformity in the π-electron distribution exists also in double linear hexagonal chains, as well as in some
other benzenoid systems. 相似文献
94.
E.H. El Abdalaoui F. Parreau A.A. Prikhod'ko 《Annales de l'Institut Henri Poincaré (B) Probabilités et Statistiques》2006,42(6):671-681
It is shown that for any family of probability measures in Ornstein type constructions, the corresponding transformation has almost surely a singular spectrum. This is a new generalization of Bourgain's theorem [J. Bourgain, On the spectral type of Ornstein class one transformations, Israel J. Math. 84 (1993) 53–63], same result is proved for Rudolph's construction [D. Rudolph, An example of a measure-preserving map with minimal self-joining and applications, J. Anal. Math. 35 (1979) 97–122]. 相似文献
95.
Thin films of silicon oxynitride have largely replaced pure silicon oxide films as gate and tunnel oxide films in modern technology due to their superior properties in terms of efficiency as boron barrier, resistance to electrical stress and high dielectric strength. A single chamber system for plasma enhanced chemical vapor deposition was employed to deposit different films of SiOxNyHz with 0.85 < x < 1.91. All films were previously characterized by Rutherford back-scattering and infrared spectroscopy to determine the stoichiometry and the presence of various bonding configurations of constituent atoms. We used X-ray reflectivity to determine the electron density profile across the depth, and we showed that the top layer is densified. Moreover, grazing incidence small-angle X-ray scattering was used to study inhomogeneities (clustering) in the films, and it is shown that plate-like inhomogeneities exist in the top and sphere-like particles at the bottom part of the film. Their shape and size depend on the stoichiometry of the films. 相似文献
96.
Xiao-jing Cai Quan-sen Jiu Chun-yan Xue 《应用数学学报(英文版)》2007,23(4):637-650
In this paper,the Dirichlet problem of Stokes approximate of non-homogeneous incompressibleNavier-Stokes equations is studied.It is shown that there exist global weak solutions as well as global andunique strong solution for this problem,under the assumption that initial density ρ_0(x)is bounded away from0 and other appropriate assumptions(see Theorem 1 and Theorem 2).The semi-Galerkin method is applied toconstruct the approximate solutions and a prior estimates are made to elaborate upon the compactness of theapproximate solutions. 相似文献
97.
M. N. El Tarazi 《BIT Numerical Mathematics》1990,30(3):484-489
The interpolation problem at uniform mesh points of a quadratic splines(x
i)=f
i,i=0, 1,...,N ands(x
0)=f0 is considered. It is known that s–f=O(h
3) and s–f=O(h
2), whereh is the step size, and that these orders cannot be improved. Contrary to recently published results we prove that superconvergence cannot occur for any particular point independent off other than mesh points wheres=f by assumption. Best error bounds for some compound formulae approximatingf
i
andf
i
(3)
are also derived. 相似文献
98.
R. E. Ansorge B. ?sman C. N. Booth L. Burow P. Carlson R. S. De Wolf B. Eckart G. Ekspong C. Fuglesang J. Gaudaen C. Geich-Gimbel B. Holl R. Hospes K. Jon-And D. P. Johnson F. Lotse N. Manthos D. J. Munday J. E. V. Ovens W. Pelzer J. G. Rushbrooke F. Triantis L. Van hamme C. Walck C. P. Ward D. R. Ward C. J. S. Webber T. O. White G. Wilquet N. Yamdagni UA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1988,41(2):179-190
A detailed analysis ofK s 0 production in \(\bar pp\) |<2.5 the average transverse momentum is found to be 0.53±0.07 GeV/c at 200 GeV and 0.62±0.08 GeV/c at 900 GeV, which is an increase with respect to data at c.m. energies below 60 GeV. TheK s 0 production cross sections in inelastic collisions are 29±4 mb at 200 GeV and 63±6 mb at 900 GeV, showing an increase compared to lower energy data. The central kaon density is found to increase as a logarithmic function of energy. At 900 GeV, where statistics are sufficient to allow one to draw conclusions, the average transverse momentum is higher in events with large charged multiplicity than in events with low multiplicity. 相似文献
99.
M. Adamus N. M. Agababyan I. V. Ajinenko Yu. A. Belokopytov H. Bia?kowska H. B?ttcher P. V. Chliapnikov F. Crijns A. De Roeck E. A. De Wolf K. Dziunikowska A. M. F. Endler W. Friebel H. Graessler P. van Hal J. K. Karamyan D. Kisielewska W. Kittel A. I. Kurnosenko B. B. Levchenko F. Meijers M. Merk A. B. Micha?owska V. I. Nikolaenko L. C. S. Oliveira K. Olkiewicz V. M. Ronjin A. M. Rybin H. M. T. Saarikko Y. T. M. Saarikko W. Schmitz L. Scholten N. A. Sotnikova J. Stepaniak O. G. Tchikilev L. A. Tikhonova V. A. Uvarov F. Verbeure R. Wischnewski EHS/NA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1988,37(2):215-229
The charged particle multiplicity distribution has been studied for non-single-diffractive π+ p andpp collisions at \(\sqrt s = 22\) GeV, for full phase space as well as for intervals in rapidity, azimuthal angle and transverse momentum. In general, the multiplicity distribution is well described by a negative binomial. From comparison of the distribution for negative or positive particles to that of all charged particles, cascading is favoured as an interpretation over stimulated emission. Interesting consequences follow from a comparison of our results to those at collider energies and toe + e ? data at comparable energy. Furthermore, evidence is given that the multiplicity distribution is not exactly of negative binomial type in every (connected or disconnected) phase space region. 相似文献
100.