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41.
Miroslav Trlifaj 《Czechoslovak Journal of Physics》1957,7(1):1-9
A theory of non-radiative transfer of excitation energy in solids is elaborated for the case of strong interaction of an atom of the sensitizer and an atom of the activator with the oscillations of the whole crystal lattice. 相似文献
42.
Miroslav Voříšek 《Czechoslovak Journal of Physics》1957,7(6):757-765
Zusammenfassung Der Scintilationsdetektor für Thermo-und Resonanzneutronen, der in dieser Arbeit beschrieben wird, wurde aus einem geschmolzenen Gemisch von ZnS(Ag) und 23 hergestellt. Bei optimalem Verhältnis beider Komponenten und optimaler Dicke des Detektors kann für Thermoneutronen eine verhältnismässig grosse Wirksamkeit erzielt werden (bis 25%). Der Detektor kann auch bei starkem Hintergrund von -Strahlung benützt werden, da die Wirksamkeit der -Strahlregistrierung durch passende Einstellung des Diskriminators unter 10–7% herabgesetzt werden kann, bei einer Wirksamkeit für Thermoneutronen von ungefähr 6%. 相似文献
43.
Miroslav Engliš 《Journal of Fourier Analysis and Applications》2007,13(3):243-265
Toeplitz operators on the Bergman space of the unit disc can be written as integrals of the symbol against an invariant operator
field of rank-one projections. We consider a generalization of the Toeplitz calculus obtained upon taking more general invariant
operator fields, and also allowing more general domains than the disc; such calculi were recently introduced and studied by
Arazy and Upmeier, but also turn up as localization operators in time-frequency analysis (witnessed by recent articles by
Wong and others) and in representation theory and mathematical physics. In particular, we establish basic properties like
boundedness or Schatten class membership of the resulting operators. A further generalization to the setting when there is
no group action present is also discussed, and the various settings in which similar operator calculi appear are briefly surveyed. 相似文献
44.
Karen Avetisyan Miroslav Pavlovi? 《Journal of Mathematical Analysis and Applications》2007,336(1):31-43
It is proved that the inequality δX(ε)?cεp, p?2, where δX is the modulus of convexity of X, is sufficient and necessary for the inequality
45.
The acetone molecule is investigated in its ground state and valence 1,3n-π*, 1,3π-π*, and 1,3σ-π* excited states and Rydberg 1,3n-3s, 1,3π-3?, 1,3n-3py and 1,3π-3py states using the CASSCF, CASPT2, and CCSD(T) methods. Equilibrium geometries of excited states are obtained and their changes with respect to the ground state are discussed. For most excited states the C2v symmetry of the ground state is lowered to the Cs symmetry. A series of valence vertical and adiabatic excitation energies is presented along with excitation energies for Rydberg states. The main body of the paper contains Finite-Field Perturbation Theory (FFPT) calculations of electric properties of the vertically as well as geometry relaxed excited states. Dipole moments of valence excited states decrease significantly upon excitation, being about one half of the ground state dipole moment. Polarizabilities usually change upon excitation much less (increase by about 30%) but hyperpolarizabilities are enhanced up to one or two orders of magnitude. The orientation of the dipole moment is reversed in some vertically excited Rydberg states. Properties of the ground and excited states are discussed considering alterations of the electronic structure and shifts in the geometry. 相似文献
46.
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
47.
Miroslav Ćirić Tatjana Petković Stojan Bogdanović 《Southeast Asian Bulletin of Mathematics》2001,25(1):47-60
In this paper we introduce a generalization of direct families of algebras and we study their limits and sums. In the case of generalized direct families of algebras carried by idempotent algebras we investigate some subdirect decompositions of their sums. The results that we obtain generalize various results given by J.L. Chrislock and T. Tamura [2], M. iri and S. Bogdanovi [3-7], H. Mitsch [13], M. Petrich [14-16], B.M. Schein [23-24] and others.Supported by Grant 04M03B of RFNS through Math. Inst. SANU 相似文献
48.
Jonathan Arazy Miroslav Englis 《Transactions of the American Mathematical Society》2003,355(2):837-864
For a domain in and a Hilbert space of analytic functions on which satisfies certain conditions, we characterize the commuting -tuples of operators on a separable Hilbert space such that is unitarily equivalent to the restriction of to an invariant subspace, where is the operator -tuple on the Hilbert space tensor product . For the unit disc and the Hardy space , this reduces to a well-known theorem of Sz.-Nagy and Foias; for a reproducing kernel Hilbert space on such that the reciprocal of its reproducing kernel is a polynomial in and , this is a recent result of Ambrozie, Müller and the second author. In this paper, we extend the latter result by treating spaces for which ceases to be a polynomial, or even has a pole: namely, the standard weighted Bergman spaces (or, rather, their analytic continuation) on a Cartan domain corresponding to the parameter in the continuous Wallach set, and reproducing kernel Hilbert spaces for which is a rational function. Further, we treat also the more general problem when the operator is replaced by , being a certain generalization of a unitary operator tuple. For the case of the spaces on Cartan domains, our results are based on an analysis of the homogeneous multiplication operators on , which seems to be of an independent interest.
49.
Miroslav Jelínek 《Czechoslovak Journal of Physics》2003,53(5):365-377
Overview of recent activities in the development of active and passive thin film waveguides, waveguide lasers and laser-deposited waveguiding films is given. Published results and parameters are summarized. The focus is on films fabricated by laser deposition. 相似文献
50.
It is well known that members of families of polynomials, that are orthogonal with respect to an inner product determined by a nonnegative measure on the real axis, satisfy a three-term recursion relation. Analogous recursion formulas are available for orthogonal Laurent polynomials with a pole at the origin. This paper investigates recursion relations for orthogonal rational functions with arbitrary prescribed real or complex conjugate poles. The number of terms in the recursion relation is shown to be related to the structure of the orthogonal rational functions. 相似文献