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Gibaek Lee Stefan L. Schweizer Ralf B. Wehrspohn 《Applied Physics A: Materials Science & Processing》2014,117(3):973-979
The lithiation and delithiation process of silicon nanowire arrays (SiNWs) on silicon substrates has been studied with high-resolution electron microscopy. The composition of lithiated SiNWs was revealed, consisting of the unreacted crystalline silicon core and the reacted amorphous Li–Si shell. In particular, the Li–Si shell was comprised of a mixture of amorphous silicon oxide and crystalline silicon, leading to hindrance during Li–Si alloying/dealloying upon cycling. 相似文献
64.
Stefan Höche Frank Krauss Thomas Teubner 《The European Physical Journal C - Particles and Fields》2008,58(1):17-28
A Markovian Monte Carlo algorithm for multi-parton production in the high-energy limit is proposed and the matching with unintegrated
parton densities is discussed. 相似文献
65.
Erik Schleicher Ringo Wenzel Margret Ahmad Alfred Batschauer Lars-Oliver Essen Kenichi Hitomi Elizabeth D. Getzoff Robert Bittl Stefan Weber Asako Okafuji 《Applied magnetic resonance》2010,37(1-4):339-352
Electron–nuclear double resonance (ENDOR) spectroscopy provides useful information on hyperfine interactions between nuclear magnetic moments and the magnetic moment of an unpaired electron spin. Because the hyperfine coupling constant reacts quite sensitively to polarity changes in the direct vicinity of the nucleus under consideration, ENDOR spectroscopy can be favorably used for the detection of subtle protein–cofactor interactions. A number of pulsed ENDOR studies on flavoproteins have been published during the past few years; most of them were designed to characterize the flavin cofactor by means of its protonation state, or to detect individual protein–cofactor interactions. The aim of this study is to compare the pulsed ENDOR spectra from different flavoproteins in terms of variations of characteristic proton hyperfine values. The general concept is to observe limits of possible influences on the cofactor’s electronic state by surrounding amino acids. Furthermore, we compare ENDOR data obtained from in vivo experiments with in vitro data to emphasize the potential of the method for gaining molecular information in complex media. 相似文献
66.
Stefan Hollands Akihiro Ishibashi Robert M. Wald 《Communications in Mathematical Physics》2007,271(3):699-722
A key result in the proof of black hole uniqueness in 4-dimensions is that a stationary black hole that is “rotating”—i.e.,
is such that the stationary Killing field is not everywhere normal to the horizon—must be axisymmetric. The proof of this
result in 4-dimensions relies on the fact that the orbits of the stationary Killing field on the horizon have the property
that they must return to the same null geodesic generator of the horizon after a certain period, P. This latter property follows, in turn, from the fact that the cross-sections of the horizon are two-dimensional spheres.
However, in spacetimes of dimension greater than 4, it is no longer true that the orbits of the stationary Killing field on
the horizon must return to the same null geodesic generator. In this paper, we prove that, nevertheless, a higher dimensional
stationary black hole that is rotating must be axisymmetric. No assumptions are made concerning the topology of the horizon
cross-sections other than that they are compact. However, we assume that the horizon is non-degenerate and, as in the 4-dimensional
proof, that the spacetime is analytic. 相似文献
67.
Roman Böttger Karl-Heinz Heinig Lothar Bischoff Bartosz Liedke Stefan Facsko 《Applied Physics A: Materials Science & Processing》2013,113(1):53-59
We show that hole patterns and sponge-like layers at irradiated Ge surfaces originate from the same driving force, namely the kinetics of ion beam induced defects in the amorphous Ge surface layer. Ge hole patterns reported earlier for irradiation with low energy (5 keV) Ga+ ions were reproduced for low energy Bi+ but also for Ge+ self-irradiation, which proves that the dominating driving force for morphology evolution cannot originate from the implanted impurities. At higher ion energies the well-known formation of sponge-like Ge surface layers after heavy ion irradiation was found for Bi+ irradiation and Ge+ self-irradiation, also. The transition from smooth surfaces via hole patterns to sponge-like morphologies with increasing ion energies was studied in detail. A model based on the kinetics of ion beam induced defects was developed and implemented in 3D kinetic Monte Carlo simulations, which reproduce the transition from hole patterns to sponge-like layers with increasing ion energy. 相似文献
68.
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
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