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941.
A. Janušauskas 《Lithuanian Mathematical Journal》1995,35(3):243-248
Institute of Mathematics and Informatics, Akademijos 4, 2600 Vilnius, Lithuania. Translated from Lietuvos Matematikos Rinkinys,
Vol. 35, No. 3, pp. 308–314, July–September, 1995. 相似文献
942.
In this paper, a pendant to a recent survey paper, the authors discuss several open problems in categorical topology. The emphasis is on topology-oriented problems rather than on more general category-oriented ones. In fact, most problems deal with full subconstructs or superconstructs of the constructTop of topological spaces and continuous maps. 相似文献
943.
J.C. Lasjaunias P. Monceau D. Starešinić K. Biljaković 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,28(2):187-190
Eur. Phys. J. B 24, 315 (2001) In our Reply to the Comment [#!1!#] we refute the “straightforward” interpretation of the excess low-temperature
specific heat, Cp, contribution we have measured in our study of CDW systems K0.3MoO3 and (TaSe4)2I [#!2!#] as originating solely from normal phonon modes. The specific sensitivity of the bump in C
p
/
T
3
at low temperatures to the impurity content is consistent with the increased value of the phason pinning gap while the dispersion
of normal phonons remains unaffected. We ascribe at least this part of the anomaly to the phason contribution. As stated in
reference [3] that the phonon density of states extracted from neutron scattering measurements is the least reliable in this
energy range (<0.5 meV), we conclude that Cp measurements are more accurate for detecting the phason contribution.
Received 17 April 2002 Published online 19 July 2002 相似文献
944.
945.
Discrete modulational instability within the first band of uniform one-dimensional waveguide arrays possessing a saturable self-defocusing nonlinearity is investigated in detail within the coupled mode approach. Explicit analytical results for both the threshold and the maximal gain of instability are compared with the corresponding data from waveguide arrays exhibiting Kerr nonlinearity. We find that saturation bounds the interval of existence of discrete modulational instability, stabilizes the frequency region of perturbations around ±π/2 and decreases both gain and critical spatial frequency of perturbations. 相似文献
946.
J. Kozánková S. C. Mojumdar J. Chocholoušek J. Kákoš M. Balog L. Krajčová 《Journal of Thermal Analysis and Calorimetry》2005,81(1):191-196
Summary DúThe aim of this work is to prepare a porous filter composed of two porous layers: macro-porous carrier and micro-porous sodium borosilicate (NBS) glass with TiO2 additive (NBST glass), a Vycor-type glass. In the present work we prepared the macroporous support from the same material (NBST glass) as the upper microporous layer and then by sintering both parts to produce the required composite. This work introduces the results of experiments in the preparation of micro-porous filter on NBST glass base, laid on macro-porous carrier. After sintering of scrap NBST glass, porous samples were prepared to be used as carriers for micro-porous samples of phase-separated NBST glass. In other cases, the following carrier materials were used: a) frita SIMAX, b) Al2O3. The properties of the NBST glass and the changes in the glass structure with temperature were studied in order to determine the optimal sintering temperature of the prepared glasses. For the development of the sintered glasses, valuable information was obtained from heating microscopy (HM) and scanning electron microscopy (SEM) studies. The combination of the HM and SEM results with the measurements of the micro-hardness and density directed to the further study of the phase separated NBST glasses. 相似文献
947.
In this first part a straight general wave-guide with a perfectly conducting outer wall and several dielectrics, excited by an electrically generally polarized matter is considered and the electromagnetic field is determined. 相似文献
948.
949.
We consider a model describing finitely many free Fermi gas reservoirs coupled by local interactions and prove the Green–Kubo
formulas and the Onsager reciprocity relations for heat and charge fluxes generated by temperature and chemical potential
differentials.
Submitted: September 2, 2006. Accepted: November 21, 2006. 相似文献
950.
We investigate the dynamics of anN-level system linearly coupled to a field of mass-less bosons at positive temperature. Using complex deformation techniques, we develop time-dependent perturbation theory and study spectral properties of the total Hamiltonian. We also calculate the lifetime of resonances to second order in the coupling. 相似文献