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951.
T Kloks D Kratsch C.K Wong 《Journal of Algorithms in Cognition, Informatics and Logic》1998,28(2):272-289
We present two algorithms solving the minimum fill-in problem on circle graphs and on circular-arc graphs in timeO(n3). 相似文献
952.
Yu. G. Abov D. S. Denisov N. O. Elyutin S. K. Matveev Yu. I. Smirnov A. O. Éidlin F. S. Dzheparov D. V. L’vov 《Journal of Experimental and Theoretical Physics》1998,87(6):1195-1200
The asymptotic behavior of the spectra for large values of the scattering vector for the case of elastic multiple small-angle
neutron scattering (SANS) is investigated theoretically and experimentally. An expansion of the spectrum in terms of the reciprocal
of the magnitude of the momentum transfer is obtained taking account of the influence of the instrumental line. It is shown
that, to within some factor, the leading term of the expansion is identical to the differential single-scattering cross section
averaged over a statistical ensemble of particles; several subsequent terms in the expansion are calculated and the range
of applicability of the resulting expressions is determined. The asymptotic behavior of the multiple SANS spectrum is measured,
using a two-crystal neutron spectrometer, for samples of an HTSC ceramic, the alloy Fe-Ni, and Al powder. The agreement between
the experimental results and the theoretical predictions is analyzed.
Zh. éksp. Teor. Fiz. 114, 2194–2203 (December 1998) 相似文献
953.
Time-resolved photoluminescence from porous silicon coated with a diamondlike carbon film is investigated. The intensity of
the photoluminescence from the carbon film is obserd to increase after deposition, and there is an accompanying change in
the intensity and a shortwavelength shift of the photoluminescence band of porous silicon that depends on the porosity of
its original layers. These changes are explained by the formation of carbon nanoclusters on the surface of the silicon filaments.
Zh. Tekh. Fiz. 68, 83–87 (April 1998) 相似文献
954.
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
955.
956.
Studies of the influence of plastic deformation and the straining temperature on the temperature dependence of the stresses
developed in titanium nickelide shape memory alloys are described.
Zh. Tekh. Fiz. 68, 141–142 (July 1998) 相似文献
957.
958.
The magnetic phase diagrams of a two-sublattice ferrimagnet with a magnetically unstable subsystem are calculated taking account
of the susceptibility. Analytic expressions are obtained for the phase-transition fields and critical values of the parameters
of the ferrimagnet. The evolution of the magnetic phase diagrams as the susceptibility of the unstable sublattice increases
is analyzed. 相似文献
959.
T.R. Saitoh N. Hashimoto G. Sletten R.A. Bark S. Törmänen M. Bergström K. Furuno K. Furutaka G.B. Hagemann T. Hayakawa T. Komatsubara A. Maj S. Mitarai M. Oshima J. Sampson T. Shizuma P.G. Varmette 《The European Physical Journal A - Hadrons and Nuclei》1998,3(3):197-199
High-spin states in 181Ta have been studied via the 176Yb(11B,α2n) reaction at 52 MeV using the PEX array and at 57 MeV using the NORDBALL array, with α-particle detection. The previously
known, Kπ=(7/2)+ ground state band and Kπ=(9/2)− band have been extended to spins (29/2)+ and (31/2)−, respectively. Two new one-quasiparticle bands, the Kπ=(5/2)+ band built on the known (5/2)+ isomer and a Kπ=((1/2)−) band have been observed. Two other rotational bands with three-quasiparticle structure, Kπ=(15/2)− and ((19/2)+ with π(7/2)[404]ν2(1/2)[510](9/2)[624] and π(9/2)[514]ν2(1/2)[510](9/2)[624] configurations, respectively, have been newly observed. The half-life of the Kπ=((19/2)+) bandhead which decays to the head of the (15/2)− band has been measured to be 140(36) ns. However, transitions from the ((19/2)+) state to the (15/2)− band have not been observed.
Received: 26 August 1998 相似文献
960.
V. T. Astrelin A. V. Burdakov V. S. Koidan K. I. Mekler P. I. Mel’nikov V. V. Postupaev M. A. Shcheglov 《Journal of Experimental and Theoretical Physics》1998,86(3):489-500
This paper presents the results of experiments on two-stage heating of a dense plasma by a relativistic electron beam in the
GOL-3 facility. A dense plasma with a length of about a meter and a hydrogen density up to 1017 cm−3 was created in the main plasma, whose density was 1015 cm−3. In the process of interacting with the plasma, the electron beam (1 MeV, 40 kA, 4 μs) imparts its energy to the electrons of the main plasma through collective effects. The heated electrons, as they disperse
along the magnetic field lines, in turn reach the region of dense plasma and impart their energy to it by pairwise collisions.
Estimates based on experimental data are given for the parameters of the flux of hot plasma electrons, the energy released
in the dense plasma, and the energy balance of the beam-plasma system. The paper discusses the dynamics of the plasma, which
is inhomogeneous in density and temperature, including the appearance of pressure waves.
Zh. éksp. Teor. Fiz. 113, 897–917 (March 1998) 相似文献