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121.
122.
Alexander Sutor Stefan J. Rupitsch Reinhard Lerch 《Applied Physics A: Materials Science & Processing》2010,100(2):425-430
In this paper we present a model for hysteretic nonlinearities with non-local memories. This model can be applied to describe
hysteretic material behavior. Common applications are ferromagnetic or ferroelectric materials. Our model consists of an analytic
function and a Preisach operator. We define a continuous Preisach weight function and introduce a method for the identification
of the model parameters. The model parameters are customized to a set of symmetric hysteresis curves. We verify our model
for a soft magnetic material, a hard magnetic material and the ferroelectric behavior of some piezoelectric material. After
that, non-symmetric curves like the virgin curve are predicted very well by the model. It is especially useful, if forced
magnetization or polarization, that appears beyond technical saturation, come into account. 相似文献
123.
124.
Stefan Schippers Ticia Buhr Alexander Borovik Jr. Kristof Holste Alexander Perry-Sassmannshausen Karolin Mertens Simon Reinwardt Michael Martins Stephan Klumpp Kaja Schubert Sadia Bari Randolf Beerwerth Stephan Fritzsche Sandor Ricz Jonas Hellhund Alfred Müller 《X射线光谱测定》2020,49(1):11-20
The Photon-Ion Spectrometer at PETRA III—in short, PIPE—is a permanently installed user facility at the "Variable Polarization XUV Beamline" P04 of the synchrotron light source PETRA III operated by DESY in Hamburg, Germany. The careful design of the PIPE ion-optics in combination with the record-high photon flux at P04 has lead to a breakthrough in experimental studies of photon interactions with ionized small quantum systems. This short review provides an overview over the published scientific results from photon-ion merged-beams experiments at PIPE that were obtained since the start of P04 operations in 2013. The topics covered comprise photoionization of ions of astrophysical relevance, quantitative studies of multi-electron processes upon inner-shell photoexcitation and photoionization of negative and positive atomic ions, precision spectroscopy of photoionization resonances, photoionization and photofragmentation of molecular ions, and of endohedral fullerene ions. 相似文献
125.
Alexander TJ Kivshar YS Buryak AV Sammut RA 《Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics》2000,61(2):2042-2049
We analyze two-component spatial optical vortex solitons supported by parametric wave mixing processes in a nonlinear bulk medium. We study two distinct cases of such localized waves, namely, parametric vortex solitons due to phase-matched second-harmonic generation in an optical medium with competing quadratic and cubic nonlinear response, and vortex solitons in the presence of third-harmonic generation in a cubic medium. We find, analytically and numerically, the structure of two-component vortex solitons, and also investigate modulational instability of their plane-wave background. In particular, we predict and analyze in detail novel types of vortex solitons, a "halo-vortex," consisting of a two-component vortex core surrounded by a bright ring of its harmonic field, and a "ring-vortex" soliton which is a vortex in a harmonic field that guides a ring-like localized mode of the fundamental-frequency field. 相似文献
126.
To exploit the high intensity of laser radiation, we propose to select frequencies at which single-photon absorption is of too low energy and two or more photons are needed to produce states of an atom that can undergo interatomic Coulombic decay (ICD) with its neighbors. For Ne(2) it is explicitly demonstrated that the proposed multiphoton absorption scheme is much more efficient than schemes used until now, which rely on single-photon absorption. Extensive calculations on Ne(2) show how the low-energy ICD electrons and Ne(+) pairs are produced for different laser intensities and pulse durations. At higher intensities the production of Ne(+) pairs by successive ionization of the two atoms becomes competitive and the respective emitted electrons interfere with the ICD electrons. It is also shown that a measurement after a time delay can be used to determine the contribution of ICD even at high laser intensity. 相似文献
127.
Adare A Adler SS Afanasiev S Aidala C Ajitanand NN Akiba Y Al-Bataineh H Alexander J Al-Jamel A Aoki K Aphecetche L Armendariz R Aronson SH Asai J Atomssa ET Averbeck R Awes TC Azmoun B Babintsev V Baksay G Baksay L Baldisseri A Barish KN Barnes PD Bassalleck B Bathe S Batsouli S Baublis V Bauer F Bazilevsky A Belikov S Bennett R Berdnikov Y Bickley AA Bjorndal MT Boissevain JG Borel H Boyle K Brooks ML Brown DS Bruner N Bucher D Buesching H Bumazhnov V Bunce G Burward-Hoy JM Butsyk S Camard X 《Physical review letters》2007,98(23):232302
We present azimuthal angle correlations of intermediate transverse momentum (1-4 GeV/c) hadrons from dijets in Cu+Cu and Au+Au collisions at square root sNN=62.4 and 200 GeV. The away-side dijet induced azimuthal correlation is broadened, non-Gaussian, and peaked away from Delta phi=pi in central and semicentral collisions in all the systems. The broadening and peak location are found to depend upon the number of participants in the collision, but not on the collision energy or beam nuclei. These results are consistent with sound or shock wave models, but pose challenges to Cherenkov gluon radiation models. 相似文献
128.
Alexander O. Smirnov 《Letters in Mathematical Physics》2006,76(2-3):297-316
We find a new class of Fuchsian equations, with algebro-geometric solutions associated to a hyperelliptic curve. A method for calculating its arithmetic genus and branching points is suggested. Numerous examples are given. 相似文献
129.
Alexander Gersten 《Foundations of Physics》2011,41(1):88-98
We deal with Lagrangians which are not the standard scalar ones. We present a short review of tensor Lagrangians, which generate
massless free fields and the Dirac field, as well as vector and pseudovector Lagrangians for the electric and magnetic fields
of Maxwell’s equations with sources. We introduce and analyse Lagrangians which are equivalent to the Hamilton-Jacobi equation
and recast them to relativistic equations. 相似文献
130.
Ivan V. Tikhonov Vasily D. Sen' Leonid I. Borodin Evgeny M. Pliss Valery A. Golubev Alexander I. Rusakov 《Journal of Physical Organic Chemistry》2014,27(2):114-120
Acid‐catalyzed disproportionation of cyclic nitroxyl radicals R2NO? includes the half‐reactions of their oxidation to oxoammonium cations R2NO+ and reduction to hydroxylamines R2NOH. For many nitroxyl radicals, this reaction is characterized by its ~100% reversibility. Quantitative characteristics of acid–base and redox properties of the whole redox triad may be obtained from research of kinetics and equilibrium of this reaction. Here, we have examined the kinetics for the disproportionation of twenty piperidine‐, pyrroline‐, pyrrolidine‐, and imidazoline nitroxyl radicals in aqueous H2SO4, and interpreted it in terms of the excess acidity function X. The rate‐limiting step of this reaction is R2NO? oxidation by its protonated counterpart R2NOH+?. Kinetic stability of R2NO? in acidic media depends on the basicity of nitroxyl group. This basicity is influenced predominantly by protonation of another, more basic group in radical structure, and its proximity to nitroxyl group. The discovered estimates of pK values for radical cations R2NOH+? (from ?5.8 to ?12.0) indicate a very low basicity of nitroxyl groups in all commonly used R2NO?. For the first time, a linear correlation is obtained between the one‐electron reduction potentials of oxoammonium cations and the basicity of nitroxyl groups of related radicals. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献