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131.
Nonlinear Dynamics - We present a model—a modified standard map. This model has interesting properties that allow quantum–classical correspondences to be studied. For some range of... 相似文献
132.
Martowicz Adam Bryła Jakub Staszewski Wieslaw J. Ruzzene Massimo Uhl Tadeusz 《Nonlinear dynamics》2019,97(3):1911-1935
Nonlinear Dynamics - The work is primarily devoted to the peridynamic model elaborated for a solid body made of shape memory alloys (SMAs). The superelasticity effect is taken into consideration as... 相似文献
133.
Stanisław A. Różański 《Phase Transitions》2019,92(1):79-86
The volume filling fraction dependence of the effective permittivity of the nematic liquid crystal 4-n-pentyl-4’-cyanobiphenyl embedded in different porous membranes and dispersed with aerosil nanoparticles was determined using broadband dielectric spectroscopy in the frequency range from 106 to 109 Hz. The experimental data were analyzed and compared with some existing theories based on the effective medium approximation and their modifications. The obtained effective permittivities as a function of the volume filling fraction lie between the lower limits of the Wiener and Hashin–Shtrikman bounds. The observed shift of the experimental points reflects the changes in the structure of the investigated composites. 相似文献
134.
Jerzy Falandysz Michał Saniewski Tamara Zalewska Ji Zhang 《Isotopes in environmental and health studies》2019,55(3):317-324
Amanita muscaria collected from a forested area in northern Poland in 2015 were analysed for activity concentrations of 137Cs and 40K. Total K concentration values were calculated from 40K data. Mushrooms were grouped in six fruiting bodies size classes regarding to their developmental stage. The 137Cs activity concentrations declined in A. muscaria as the fruiting bodies maturated. The contents of 40K/K activity remained constant in caps at different developmental stage, while for stipes an increase was around twofold (40K from 925?±?55 Bq kg?1 dry biomass in the baby individuals and 1600?±?63–1700?±?53 Bq kg?1 dry biomass in two oldest classes). A. muscaria is a weak accumulator of 137Cs, while a steep drop in activity concentrations of this nuclide in the fruiting bodies as they maturate has not been reported earlier for mushrooms. Clearly, a fate of 137Cs in A. muscaria is highly different from that of 40K/K that is an essential element to fungi. In parallel, an observed increase in the content of 40K/K in stipes of fruiting bodies with developmental state can be related to its ‘hardening’ and more fibrous nature with age and basic function to support the cap, but this has not been studied. 相似文献
135.
Potential Analysis - We study the quenched long time behaviour of the survival probability up to time t, $mathbf {E}_{x}left [e^{-{{int }_{0}^{t}} V^{omega }(X_{s})mathrm {d}s}right ],$ of a... 相似文献
136.
Nonlinear Dynamics - Dynamics of magnetized fluids is much more complex than expected from the standard magnetohydrodynamics. Besides chaotic behavior that often appears in nonlinear dynamical... 相似文献
137.
A Comparative Study of Solutions of Silk Fibroin in 1-Butyl-3-methylimidazolium Chloride and Acetate
A. I. Susanin E. S. Sashina P. Ziółkowski V. V. Zakharov M. Zaborski M. Dziubiński P. Owczarz 《Russian Journal of Applied Chemistry》2018,91(4):647-652
A comparative study of the molecular-mass characteristics and rheological properties of solutions of silk fibroin in 1-butyl-3-methylimidazolium chloride and acetate was made. 相似文献
138.
Trapping centers related to P+ and B+ ions implanted in the SiO2 layer as well as traps introduced into SiO2 during boron implantation through the oxide into the silicon substrate have been investigated. The internal photoemission method has been used to estimate their capture cross section and total densityN
t
. 相似文献
139.
I. Strzałkowski M. Marczewski M. Kowalski J. Wisłowski 《Applied Physics A: Materials Science & Processing》1990,51(1):19-22
The experimental method used in this work is based upon the idea of nonavalanche injection of carriers heated by direct electric field. The structure consisted of an n-channel MOS transistor and two p-n junctions. The process of charge injection in this structure was investigated by studying the dependence of gate current on heating voltage. The trapping properties of the SiO2 film were studied by monitoring the charging of the film during injection of electrons. The capture cross-sections, the trap centre concentrations and the dependence of the capture cross section on the electric field for fields between 1 MV/cm and 2.5 MV/cm were determined. 相似文献
140.
In this paper some decompositions of Cauchy polynomials, Ferrers-Jackson polynomials and polynomials of the form x
2n
+ y
2n
, n ∈ ℕ, are studied. These decompositions are used to generate the identities for powers of Fibonacci and Lucas numbers as well
as for powers of the so called conjugate recurrence sequences. Also, some new identities for Chebyshev polynomials of the
first kind are presented here. 相似文献