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81.
Nonlinear Dynamics - 相似文献
82.
Faisal Zeeshan Joanna Hoszowska Jean-Claude Dousse Dimosthenis Sokaras Tsu-Chien Weng Roberto Alonso-Mori Matjaz Kavčič Mauro Guerra Jorge Miguel Sampaio Fernando Parente Paul Indelicato José Pires Marques José Paulo Santos 《X射线光谱测定》2019,48(5):351-359
We report on measurements of the Kβ diagram, valence-to-core (VtC), and hypersatellite X-ray spectra induced in metallic Cr by photon single and double K-shell ionization. The experiment was carried out at the Stanford Synchrotron Radiation Lightsource using the seven-crystal Johann-type hard X-ray spectrometer of the beamline 6-2. For the Kβ diagram and VtC transitions, the present study confirms the line shape features observed in previous works, whereas the Khβ hypersatellite transition was found to exhibit a complex spectral line shape and a characteristic low-energy shoulder. The energy shift of the hypersatellite relative to the parent diagram line was deduced from the measurements and compared with the result of extensive multiconfiguration Dirac–Fock (MCDF) calculations. A very good agreement between experiment and theory was found. The MCDF calculations were also used to compute the theoretical line shape of the hypersatellite. A satisfactory agreement was obtained between the overall shapes of the experimental and theoretical spectra, but deviations were observed on the low- and high-energy flanks of the hypersatellite line. The discrepancies were explained by chemical effects, which were not considered in the MCDF calculations performed for isolated atoms. 相似文献
83.
Ortiz Adolfo Yang Jianhua Coccolo Mattia Seoane Jesús M. Sanjuán Miguel A. F. 《Nonlinear dynamics》2020,102(4):2323-2337
Nonlinear Dynamics - The main purpose of this paper is to study both the underdamped and the overdamped dynamics of the nonlinear Helmholtz oscillator with a fractional-order damping. For that... 相似文献
84.
Nieto Alexandre R. Zotos Euaggelos E. Seoane Jesús M. Sanjuán Miguel A. F. 《Nonlinear dynamics》2020,99(4):3029-3039
Nonlinear Dynamics - We show that the presence of KAM islands in nonhyperbolic chaotic scattering has deep implications on the unpredictability of open Hamiltonian systems. When the energy of the... 相似文献
85.
Journal of Thermal Analysis and Calorimetry - In this paper, a three-dimensional analysis is used to study the heat transfer and fluid flow characteristics in ducts with various cross-sectional... 相似文献
86.
Nonlinear Dynamics - Delay-coordinate maps have been widely used recently to study nonlinear dynamical systems, where there is only access to the time series of one of their variables. Here, we... 相似文献
87.
88.
A class of non-linear Fokker Planck equations with exactly known steady state solution is investigated and its relation with the models considered earlier in the literature is discussed. A characterisation of the absence of detailed balance and possible existence of limit cycles is given. The implications of detailed balance on the existence and the character of limit cycle behaviour are studied. It is shown that detailed balance does not determine the existence or non-existence of limit cycles but rather their character. 相似文献
89.
90.
The semigroup of values of irreducible space curve singularities
is the set of intersection multiplicities among hypersurfaces
and the given curve. It is an invariant of the singularity, and
for plane curves it characterizes the equisingularity type
considered by Zariski. For space curve singularities the semigroup
of values is a numerical semigroup and it can not be computed by
means of the exponents of any Puiseux parametrization, as in the
plane case. We obtain an algorithm for calculating the semigroup
of values of a space curve singularity, which determines the
generators of the semigroup and the valuation ideals associated
with the semigroup. We give a Maple version of the algorithm. 相似文献