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1.
The electronic spectrum of an icosahedral quasicrystal with a central-atom decoration of the Amman-Mackay network is investigated
in the tight-binding approximation. The quasicrystal is described as a structural limit of the optimal cubic approximants
with increasing period. The electronic spectra for the first four optimal cubic approximants do not contain the hierarchical
gap structure which is typical for the Cantor set of the spectrum of a one-dimensional quasicrystal. At the same time, as
the order of the approximant increases, the spectrum becomes singular throughout the entire energy scale.
Pis’ma Zh. éksp. Teor. Fiz. 67, No. 8, 557–562 (25 April 1998)
Published in English in the original Russian journal. Edited by Steve Torstveit. 相似文献
2.
We study the possibility of defining the (braided) comultiplication for the GL
q
(N)-covariant differential complexes on some quantum spaces. We discover suchdifferential bialgebras (and Hopf algebras) on the bosonic and fermionic quantum hyperplanes (with additive coproduct) and on the braided matrix algebra BM
q
(N) with both multiplicative and additive coproducts. The latter case is related (forN = 2) to theq-Minkowski space andq-Poincaré algebra. 相似文献
3.
A specific quantum Lax operator, forming a quantum U
q
(sl
n) chain, is suggested. The intertwining R
L
L relation is proved. The invariant local 2+1-dimensional reformulation of the auxiliary linear problem for the L-operator is discussed. 相似文献
4.
This paper significantly extends and generalizes the paragrassmann calculus of our previous paper [1]. Here we discuss explicit general constructions for paragrassmann calculus with one and many variables. For one variable, nondegenerate differentiation algebras are identified and shown to be equivalent to the algebra of (p+1)×(p+1) complex matrices. If (p+1) is a prime integer, the algebra is nondegenerate and so unique. We then give a general construction of many-variable diffeentiation algebras. Some particular examples are related to multi-parametric quantum deformations of the harmonic oscillators.Dedication This paper is in memory of Mikhail Constantinovich Polivanov. One of the authors (A.T.F.) had a privilege to be a friend of him for many and many years. He was not only a distinguished scientist but a true Russian intellectual having deep roots in Russian culture. It is a deep sorrow that we can no more have a talk with him on science, poetry, religion ...Laboratory of Theoretical Physics, JINR, Dubna. SU-101 000 Moscow, Russia. Published in Teoreticheskaya i Matematicheskaya Fizika, Vol. 94, No. 2, pp. 213–231, February, 1993. 相似文献
5.
6.
7.
V. A. Postnikov Ts. V. Kakuliya L. M. Khananashvili Yu. V. Isaev Yu. N. Novikov M. E. Vol'pin 《Russian Chemical Bulletin》1979,28(3):626-627
Conclusions The stirred reaction of graphite with molten lithium gave compounds of composition C6Li, C12Li, and C18Li, for which the identity periods and thicknesses of the filled layers were determined.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 671–672, March, 1979. 相似文献
8.
9.
M. I. Isaev 《Chemistry of Natural Compounds》1994,29(6):740-743
A method has been developed for the regioselective glycosylation of 20,24-epoxycycloartane-16,25-diols. Two glycosides have been synthesized from askendoside D: askendoside D 16-O-acetate 25-O--L-rhamnopyranoside (V) and askendoside B 16,25-di-O--L-rhamnopyranoside (VI).Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 830–835, November–December, 1993. 相似文献
10.
The structures of two new cycloartane triterpenoids, cycloalpigenin A and cycloalpioside A, isolated from Astragalus alopecurus Pall. (Leguminosae) have been established on the basis of chemical transformations together with1H,13C, and 2D1H-1H and1H-13C chemical shift correlation NMR spectroscopy and IR, mass, and CD spectra. Cycloalpigenin A is 3,16,25-trihydroxy-20R,24S-epoxycycloartan-12-one, and cycloalpioside A is cycloalpigenin A 3-O--D-xylopyranoside.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, FAX (3712) 62 73 48. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 379–385, May–June, 1994. 相似文献