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971.
A method was developed for the determination of largest Lyapunov index for short chaotic time sequences with allowance for
the presence of noise in the response of the system. For this purpose a simple unidimensional representation modelling the
dynamics of irregular self-oscillations was investigated. Conditions were found for adequate determination of the largest
Lyapunov index from the noise-distorted signals. The results were used to obtain the largest Lyapunov index for the Belousov—Zhabotinskii
reaction taking place in an ideal-mixing closed reactor and in a constant-mixing flow-type reactor.
Institute of Organic Chemistry, National Academy of Sciences of Ukraine. Translated from Teoreticheskaya i éksperimental’naya
Khimiya, Vol. 33, No. 3, pp. 136–142, May–June, 1997. 相似文献
972.
V. V. Kokorin V. A. Chernenko J. Pons C. Segui E. Cesari 《Physics of the Solid State》1997,39(3):485-487
Anomalies have been detected in the temperature behavior of the physical properties of Ni2MnGa in the temperature interval preceding the martensitic transformation, which is attributed to TA
2 phonon mode condensation at T=T
I>T
m (T
m is the martensitic transition temperature).
Fiz. Tverd. Tela (St. Petersburg) 39, 557–559 (March 1997) 相似文献
973.
We have performed experiments in which self-generation of dark envelope solitons for spin waves at microwave frequencies were
obtained. Stable self-generation of dark solitons was observed in a ring consisting of tangentially magnetized yttrium iron
garnet film and a microwave signal amplifier.
Pis’ma Zh. éksp. Teor. Fiz. 68, No. 3, 229–233 (10 August 1998) 相似文献
974.
Magnetic-field-induced polymorphism of biperiodic stripe domain structures of films with a positive anisotropy constant and
easy axis parallel to the normal to the surface is studied. A symmetry classification of the observed types of domain structures
is performed, and the phase diagram of the films in the (H
⊥, H
∥) plane, where H
⊥ and H
∥ are, respectively, the components of the magnetic field vector perpendicular and parallel to the normal to the surface, is
determined.
Pis’ma Zh. éksp. Teor. Fiz. 67, No. 9, 701–706 (10 May 1998) 相似文献
975.
Zólomy A. Berceli T. Járó G. Hilt A. Marozsák T. 《Optical and Quantum Electronics》1998,30(11-12):969-983
Optical and Quantum Electronics - A new approach for the design and construction of low noise broadband optical receivers is presented utilizing distributed amplification based on hybrid integrated... 相似文献
976.
The magnetization and paramagnetic susceptibility of the system of compounds Zn1−x
CuxCr2S4 (0<x⩽1) are investigated at low temperatures. It is shown that as the content of Cu increases the system exhibits a transition
from an antiferromagnetic to a ferromagnetic state.
Fiz. Tverd. Tela (St. Petersburg) 40, 278–279 (February 1998) 相似文献
977.
O. Ya. Butkovskii Yu. A. Kravtsov E. D. Surovyatkina 《Journal of Experimental and Theoretical Physics》1998,86(1):206-212
The structure of the attraction zones of the final states associated with dynamical period doubling bifurcations is investigated.
It is found that on the “initial value—transition rate” plane the attraction zones of the two possible final states alternate
with each other and that a subdivision of the attraction regions occurs with a decrease in the transition rate. It is shown
that the boundaries of the attraction zones are smeared out because of the effect of noise and in this situation the fine
structure of the attraction zones is destroyed. As analytical and numerical calculations have shown, the critical value of
the noise variance, corresponding to the boundary between the dynamical (or predictable) and stochastic (or unpredictable)
modes, has a power-law dependence on the transition rate with a typical exponent value of one. The existence of “noise” invariants
is also observed: the integrated (over all initial values) probability of achieving the final state is invariant with respect
to the noise level.
Zh. éksp. Teor. Fiz. 113, 369–380 (January 1998) 相似文献
978.
E. G. Sheikin 《Technical Physics》1998,43(9):1039-1042
Based on a theory of the passage of low-energy, heavy ions through matter, simple analytical expressions are obtained for
calculating the average projected ranges of the ions and the rms deviations of the projected ranges. The theoretical and experimental
ranges of heavy ions with atomic numbers 29⩽Z
1⩽83 in targets of Be, B, C, and Si are compared. The theory is found to be in good agreement with experiment.
Zh. Tekh. Fiz. 68, 33–36 (September 1998) 相似文献
979.
Experiments on permanent lattice-defect formation induced by electronic excitation of rare-gas solids are presented. The creation
of triplet excitons Γ(3/2) is found to be the primary process, followed by the exciton self-trapping. Probable models of defect
formation are discussed.
Fiz. Tverd. Tela (St. Petersburg) 40, 903–906 (May 1998)
Published in English in the original Russian journal. Reproduced here with stylistic changes by the Translation Editor. 相似文献
980.
E. Kolbe K. Langanke F.-K. Thielemann 《The European Physical Journal A - Hadrons and Nuclei》1998,3(4):389-396
We study the influence of a strange axial vector form factor Gs of the nucleon on the neutrino-induced proton and neutron knockout of 16O. In particular, we calculate how much Gs≠0 might affect the recently proposed signal for supernova νμ and ντ neutrinos in the Superkamiokande detector. We discuss whether Superkamiokande might be able to determine the value of Gs in a hypothetical neutrino-beam experiment. Finally we comment on the possible effect Gs≠0 might have on neutrino-nucleus cross sections in the neutrino-driven wind model for the nuclear r-process.
Received: 30 April 1998 / Revised version: 10 August 1998 相似文献