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81.
For a given pair such that A is cyclic and b is a cyclic generator (with respect to A) of , it is shown that for every nonnegative integer m we can find a nonnegative integer t and a sequence ,so that a the zeros of the rational function det P(z), where f, lie in the open unit disc in the complex plane. The result is directly applicable to a stabilizability problem for linear systems with a time delay in control action. 相似文献
82.
We consider the capacity of classical information transfer for noiseless quantum channels carrying a finite average number of massive bosons and fermions. The maximum capacity is attained by transferring the Fock states generated from the grand-canonical ensemble. Interestingly, the channel capacity for a Bose gas indicates the onset of Bose-Einstein condensation, by changing its qualitative behavior at the criticality, while for a channel carrying weakly attractive fermions, it exhibits the signatures of Bardeen-Cooper-Schrieffer transition. We also show that, for noninteracting particles, fermions are better carriers of information than bosons. 相似文献
83.
We present a determination of a new class of three-loop Feynman diagrams describing heavy-to-light transitions. We apply it to find the O(alpha2(s)) corrections to the top quark decay t --> bW and to the distribution of lepton invariant mass in the semileptonic b quark decay b --> ulnu. We also confirm the previously determined total rate of that process as well as the O(alpha2) corrections to the muon lifetime. 相似文献
84.
85.
GSH and L-His are abundant biomolecules and likely biological ligands for Zn(II) under certain conditions. Potentiometric titrations provide evidence of formation of ternary Zn(II) complexes with GSH and L-His or D-His with slight stereoselectivity in favour of L-His (ca. 1 log unit of stability constant). The solution structure of the ZnH(GSH)(L-His)(H2O) complex at pH 6.8, determined by NMR, includes tridentate L-His, monodentate (sulfur) GSH, and weak interligand interactions. Calculations of competitivity of this complex for Zn(II) binding at pH 7.4 indicate that it is likely to be formed in vivo under conditions of GSH depletion. Otherwise, GSH alone emerges as a likely Zn(II) carrier. 相似文献
86.
A definition of a generalized filled-in Julia set generated by an infinite array of proper polynomial mappings in is introduced. It is shown that such Julia sets depend analytically on the defining polynomial mappings. 相似文献
87.
Maciej P. Wojtkowski 《Communications in Mathematical Physics》2007,273(2):283-304
We formulate a general framework for the construction of hyperbolic billiards.
Spherical symmetry is exploited for a simple treatment of billiards with spherical
caps and soft billiards in higher dimensions. Other examples include the Papenbrock
stadium.
Reproduction of the entire article for non-commercial purposes is permitted without charge. 相似文献
88.
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90.
Maciej Kubicki Teresa Borowiak Jerzy Suwiński Paweł Wagner 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(1):106-108
Crystalline 4-nitro-1-phenylimidazole, C9H7N3O2, (I), and 4′-nitro-1-phenyl-4,1′-biiimidazole, C12H9N5O2, (II), contain C—H⃛O and C—H⃛N hydrogen bonds, connecting the molecules into infinite chains. The aromatic fragments in both compounds are nearly planar. The dihedral angles between the benzene and imidazole rings are 26.78 (5)° in (I) and 29.36 (8)° in (II). 相似文献