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141.
142.
A simple self-contained proof of Sanov's theorem in τ-topology is given, well suited for a first course on large deviations. *This work was supported by the Hungarian National Foundation for Scientific Research under Grant T046376  相似文献   
143.
On the basis of a plane-wave spectrum representation, the polarization features of a transverse quasimonochromatic non-paraxial field have been studied. A relationship has been established between the polarization characteristics in the near field and the coherence and symmetry properties of the beam in the far field.  相似文献   
144.
We establish a mechanism for energy localization in regions of the sugar-phosphate RNA backbone which leads to the formation of transesterification or hydrolysis hot spots. In particular, our results account for the site specificity of the covalent cyclization and cycle reopening in the catalytic intervening sequence (IVS) of a ribosomal RNA.  相似文献   
145.
Photosystem II core antenna of blue-green algae Synechococcus isolated in gel was studied by optical hole burning spectroscopy at 4·2 K. Persistent holes were burned into fluorescence spectra throughout the region 680–696 nm. The hole width extrapolated to zero burning fluence yielded a value 1·0±0·2 cm–1. A theoretical interpretation of the hole profile in fluorescence is presented. The dependence of saturated hole depth on burning wavelength is related to inhomogeneous site distribution function.Authors would like to thank F. Vácha from the Dept. of Biochemistry, Faculty of Nature Sciences, Charles University, for the preparation of the samples.  相似文献   
146.
Our object of study is the asymptotic behavior of the sequence of polynomials orthogonal with respect to the discrete Sobolev inner product <formula> \langle f, g \rangle = ∈t_{E} f(ξ) \overline{g(ξ)} ρ(ξ) |d ξ|+ f(Z) A g(Z)^H, </formula> where E is a rectifiable Jordan curve or arc in the complex plane f(Z) = (f(z_1), \ldots, f^{(l_1)}(z_1) , \ldots , f(z_m) , \ldots ,f^{(l_m)}(z_m)), A is an M \times M Hermitian matrix, M l 1 + ⋅s + l m + m , |d ξ| denotes the arc length measure, ρ is a nonnegative function on E , and z i ∈Ω, i=1,2,\ldots,m , where Ω is the exterior region to E . July 23, 1999. Dates revised: September 11, 2000 and February 16, 2001. Date accepted: February 26, 2001.  相似文献   
147.
It was studied the tin phase composition of the electrodeposited alloys produced at different temperatures and current densities from an acid chloride/fluoride electrolyte and an acid chloride bath. Mössbauer spectra were consistent with a Ni3Sn4 intermetallic compound, dissolved tin, and a Cu?Sn intermetallic compound formed at the interface of the copper substrate.  相似文献   
148.
A pair of coupled classical oscillators with a general potential and general form of coupling is investigated. For general potentials, the single-frequency solution is shown to be stable for small excitations. For special potentials, such system remains stable for an arbitrary excitation. In both cases, the stability does not depend on the form of coupling. Transition to the instability regime follows from the way how nonlinear potential entrains the energy transfer between the oscillators. Relation between the existence of multi-frequency quasi-periodic or periodic solutions and the instability of single-frequency ones is discussed.  相似文献   
149.
A new way of expounding analytical properties based on their mutual dependence (complementary and contradictory relationships) and their unequivocal connection with analytical quality facets is presented. To this end, the paper provides answers to the obvious questions that arise in dealing with the subject: why?, how?, when? and where to teach analytical properties in the Analytical Chemistry curriculum?  相似文献   
150.
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