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1.
2.
Let ir(G) and γ(G) be the irredundance number and the domination number of a graph G, respectively. A graph G is called irredundance perfect if ir(H)=γ(H), for every induced subgraph H of G. In this article we present a result which immediately implies three known conjectures on irredundance perfect graphs. © 2002 Wiley Periodicals, Inc. J Graph Theory 41: 292–306, 2002 相似文献
3.
4.
Vadim G. Kessler 《Journal of Sol-Gel Science and Technology》2004,32(1-3):11-17
The article describes the principles of the Single Source Precursor approach to inorganic materials and introduces the Geometrical Molecular Structure Design Concept (MSDC) based on the choice of a proper molecular structure type for the desired precursor and completing it with ligands providing both the necessary number of donor atoms and the sterical protection of the chosen core. Application of MSDC is illustrated with examples taken from development of new approaches in the synthesis of oxide and sulfide catalysts and ferroelectric oxide materials. 相似文献
5.
D. Fong J. H. Hamilton A. V. Ramayya J. K. Hwang C. Goodin K. Li J. Kormicki J. O. Rasmussen Y. X. Luo S. C. Wu I. Y. Lee A. V. Daniel G. M. Ter-Akopian G. S. Popeko A. S. Fomichev A. M. Rodin Yu. Ts. Oganessian M. Jandel J. Kliman L. Krupa J. D. Cole M. A. Stoyer R. Donangelo W. C. Ma 《Physics of Atomic Nuclei》2006,69(7):1161-1167
The hot bimodal fission of 252Cf is reexamined with new high-statistics data. We constructed a γ-γ-γ coincidence cube for binary fission and LCP-gated γ-γ matrix for ternary fission. By identifying the secondary fission fragments from their γ-ray transitions, we measured the yields for various fission splits. The normal neutron yield distribution is found to be
Gaussian for Xe-Ru. However, the binary fission split of Ba-Mo is found to exhibit a bimodal neutron distribution with the
“hot mode” corresponding to ≈3.1% of the total yield. In α ternary fission, the first measurements of yields for specific fission splits are presented. The Te-α-Ru and Xe-α-Mo neutron yields fit well with a single mode, but the Ba-α-Zr split shows evidence for an enhanced hot mode with an intensity of ≈13.8% of the normal mode.
The text was submitted by the authors in English. 相似文献
6.
7.
Vadim Kaimanovich 《Israel Journal of Mathematics》1995,89(1-3):77-134
Covering Markov operators are a measure theoretical generalization of both random walks on groups and the Brownian motion
on covering manifolds. In this general setup we obtain several results on ergodic properties of their Poisson boundaries,
in particular, that the Poisson boundary is always infinite if the deck group is non-amenable, and that the deck group action
on the Poisson boundary is amenable. For corecurrent operators we show that the Radon-Nikodym cocycles of two quotients of
the Poisson boundary are cohomologous iff these quotients coincide. It implies that the Poisson boundary is either purely
non-atomic or trivial, and that the action of any normal subgroup of the deck group on the Poisson boundary is conservative.
We show that the Poisson boundary is trivial for any corecurrent covering operator with a nilpotent (or, more generally, hypercentral)
deck group. Other applications and examples are discussed.
Supported by a British SERC Advanced Fellowship. A part of this work was done during my stay at MSRI, Berkeley supported by
NSF Grant DMS 8505550. 相似文献
8.
V. A. Rodin 《Mathematical Notes》1992,52(2):863-865
Translated from Matematicheskie Zametki, Vol. 52, No. 2, pp. 152–154, August, 1992. 相似文献
9.
G. M. Ter-Akopian A. V. Daniel A. S. Fomichev G. S. Popeko A. M. Rodin Yu. Ts. Oganessian J. H. Hamilton A. V. Ramayya J. Kormicki J. K. Hwang D. Fong P. Gore J. D. Cole M. Jandel J. Kliman L. Krupa J. O. Rasmussen I. Y. Lee A. O. Macchiavelli P. Fallon M. A. Stoyer R. Donangelo S. -C. Wu W. Greiner 《Physics of Atomic Nuclei》2004,67(10):1860-1865
Ternary fission of 252Cf was studied at Gammasphere using eight ΔE×E particle telescopes. Helium, beryllium, boron, and carbon light charged particles (LCPs) emitted with kinetic energy more than 9, 21, 26, and 32 MeV, respectively, were identified. The 3368-keV γ transition from the first 2+ excited state in 10Be was found and the population probability ratio N(2+)/N(0+) = 0.160 ± 0.025 was estimated. No evidence was found for 3368-keV γ rays emitted from a triple molecular state. For the first time, charge distributions are obtained for ternary fission fragments emitted with helium, beryllium, and carbon LCPs. 相似文献
10.
We consider a class of homogeneous manifolds including all semisimple coadjoint orbits. We describe manifolds of that class
admitting deformation quantizations equivariant under the action ofG and the corresponding quantum group. We also classify Poisson brackets relating to such quantizations.
Presented at the 11th Colloquium “Quantum Groups and Integrable Systems”, Prague, 20–22 June 2002. 相似文献