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Sebastian Aland Stephan Schwarz Jochen Fröhlich Axel Voigt 《The European physical journal. Special topics》2013,220(1):185-194
In simulations of liquid metals, various model approximations, each of which justified by experimental results lead to a simplified two-phase flow problem. This paper discusses numerical justifications for these approaches and provides quantitative results for a single rising bubble as a benchmark. Representing a bubble as a rigid object is shown to be valid for low Eötvös numbers in contaminated systems. Qualitative differences can be observed for larger Eötvös numbers. Further simulations are undertaken with different ratios of inner and outer viscosity. The benchmark problem considered may also be interesting for more general applications. 相似文献
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Bozena Pietrzyk Sebastian Miszczak Hieronim Szymanowski Anna Sobczyk-Guzenda Zbigniew Gawronski 《Journal of Sol-Gel Science and Technology》2013,68(3):455-463
The sol–gel process is widely used for the production of powders, coatings and bulk materials. However, being a wet-chemical technique, it has certain limitations related to properties of aqueous colloidal solution, especially when applied as a coating. The most frequently used methods, such as dip- and spin-coating, are difficult to apply onto more complex substrates. In these cases, the aerosol–gel deposition method can be regarded as the solution of this problem. In the present article, a novel plasma enhanced aerosol–gel method of coatings production is presented. A novelty of this method is based on an integration of the aerosol–gel deposition of thin films and their low temperature plasma treatment. Owing to the above, all stages of the coatings production process—substrate preparation, film deposition, and its plasma treatment, can be carried out in a single reactor. The design and operational scheme of such device is presented in this work. Using this device, thin coatings were first deposited on substrates and then plasma treated. The effect of deposition and plasma discharge conditions on morphology and chemical structure of the films has been studied. It was found that plasma treatment had a substantial influence on all the examined properties of the aerosol–gel deposited coatings. 相似文献
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Jorge Segovia Chen Chen Ian C. Cloët Craig D. Roberts Sebastian M. Schmidt Shaolong Wan 《Few-Body Systems》2014,55(1):1-33
Predictions obtained with a confining, symmetry-preserving treatment of a vector ? vector contact interaction at leading-order in a widely used truncation of QCD’s Dyson–Schwinger equations are presented for Δ and Ω baryon elastic form factors and the γN → Δ transition form factors. This simple framework produces results that are practically indistinguishable from the best otherwise available, an outcome which highlights that the key to describing many features of baryons and unifying them with the properties of mesons is a veracious expression of dynamical chiral symmetry breaking in the hadron bound-state problem. The following specific results are of particular interest. The Δ elastic form factors are very sensitive to m Δ. Hence, given that the parameters which define extant simulations of lattice-regularised QCD produce Δ-resonance masses that are very large, the form factors obtained therewith are a poor guide to properties of the Δ(1232). Considering the Δ-baryon’s quadrupole moment, whilst all computations produce a negative value, the conflict between theoretical predictions entails that it is currently impossible to reach a sound conclusion on the nature of the Δ-baryon’s deformation in the infinite momentum frame. Results for analogous properties of the Ω baryon are less contentious. In connection with the N → Δ transition, the Ash-convention magnetic transition form factor falls faster than the neutron’s magnetic form factor and nonzero values for the associated quadrupole ratios reveal the impact of quark orbital angular momentum within the nucleon and Δ; and, furthermore, these quadrupole ratios do slowly approach their anticipated asymptotic limits. 相似文献
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Sebastian Fortin Olimpia Lombardi Juan Camilo Martínez González 《Foundations of Chemistry》2016,18(3):225-240
In the present paper we address the problem of optical isomerism embodied in the socalled “Hund’s paradox”, which points to the difficulty to account for chirality by means of quantum mechanics. In particular, we explain the answer to the problem proposed by the theory of decoherence. The purpose of this article is to challenge this answer on the basis of a conceptual analysis of the phenomenon of decoherence, that reveals the limitations of the theory of decoherence to solve the difficulties posed by optical isomerism and, in general, by quantum measurement. 相似文献