TY  - JOUR
A1  - Abel, Markus
A1  - Celani, A.
A1  - Vergeni, D.
A1  - Vulpiani, A.
T1  - Front propagation in laminar flows
N2  - The Problem of front propagation in flowing media is addressed for laminar velocity fields in two dimensions. Three representative cases are discussed: stationary cellular flow, stationary shear flow, and percolating flow. Production terms of Fisher-Kolmogorov-Petrovskii-Piskunov type and of Arrhenius type are considered under the assumption of no feedback of the concentration on the velocity. Numerical simulations of advection-reaction-diffusion equations have been performed by an algorithm based on discrete-time maps. The results show a generic enhancement of the speed of front propagation by the underlying flow. For small molecular diffusivity, the front speed <i>V<sub><i>f</sub> depends on the typical flow velocity <i>U as<sup> </sup>a power law with an exponent depending on the topological properties of the flow, and on the ratio of reactive and advective time scales. For open-streamline flows we find always<sup> </sup><i>V<sub><i>f</sub>~<i>U, whereas for cellular flows we observe <i>V<sub><i>f</ sub>~<i>U<sup>1/4</sup> for fast advection and <i>V<sub><i>f</sub>~<i>U<sup>3/4</sup> for slow advection.
Y1  - 2001
UR  - http://www.stat.physik.uni-potsdam.de/~markus/papers/PRE64-46307-1.pdf
ER  - 
TY  - JOUR
A1  - Afshaarvahid, Shahraam
A1  - Heuer, Axel
A1  - Menzel, Ralf
A1  - Munch, Jesper
T1  - Temporal structure of stimulated-Brillouin-scattering reflectivity considering transversal-mode development
Y1  - 2001
ER  - 
TY  - JOUR
A1  - Ahlers, Volker
A1  - Zillmer, Rüdiger
A1  - Pikovskij, Arkadij
T1  - Lyapunov exponents in disordered chaotic systems : avoided crossing and level statistics
N2  - The behavior of the Lyapunov exponents (LEs) of a disordered system consisting of mutually coupled chaotic maps with different parameters is studied. The LEs are demonstrated to exhibit avoided crossing and level repulsion, qualitatively similar to the behavior of energy levels in quantum chaos. Recent results for the coupling dependence of the LEs of two coupled chaotic systems are used to explain the phenomenon and to derive an approximate expression for the distribution functions of LE spacings. The depletion of the level spacing distribution is shown to be exponentially strong at small values. The results are interpreted in terms of the random matrix theory.
Y1  - 2001
ER  - 
TY  - JOUR
A1  - Anishchenko, Vadim S.
A1  - Vadivasova, T. E.
A1  - Kopeikin, A. S.
A1  - Kurths, Jürgen
A1  - Strelkova, G. I.
T1  - Effect of noise on the relaxation to an invariant probability measure of nonhyperbolic chaotic attractors
Y1  - 2001
ER  - 
TY  - JOUR
A1  - Audenaert, Katrien
A1  - Eisert, Jens
A1  - Jane, E.
A1  - Plenio, M. B.
A1  - Virmani, S.
A1  - Moor, B. D.
T1  - The asymptotic relative entropy of entanglement
N2  - We present an analytical formula for the asymptotic relative entropy of entanglement for Werner states of arbitrary dimensionality. We then demonstrate its validity using methods from convex optimization. This is the first case in which the value of a subadditive entanglement measure has been obtained in the asymptotic limit. This formula also gives the sharpest known upper bound on the distillable entanglement of these states.
Y1  - 2001
ER  - 
TY  - JOUR
A1  - Avilov, Anatoly S.
A1  - Lepeshov, G. G.
A1  - Pietsch, Ullrich
A1  - Tsirelson, Vladimir G.
T1  - Multipole analysis of the electron density and electrostatic potential in Germanium by high-resolution electron diffraction
Y1  - 2001
SN  - 0022-3697
ER  - 
TY  - BOOK
A1  - Backhaus, Udo
A1  - Schön, Lutz-Helmut
ED  - Mikelskis, Helmut
ED  - Wilke, Hans-Joachim
T1  - Physik plus : Kl. 8, [Hauptbd.], Gymnasium Nordrhein-Westfalen
Y1  - 2001
SN  - 3-06-020840-9
PB  - Volk und Wissen Verl.
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Beck, Michael
A1  - Stiel, H.
A1  - Leupold, Dieter
A1  - Winter, Bernd
A1  - Pop, D.
A1  - Vogt, U.
A1  - Spitz, Christian
T1  - Evaluation of the energetic position of the lowest excited singlet state of ß-carotene by NEXAFS and photoemission spectroscopy
Y1  - 2001
ER  - 
TY  - THES
A1  - Becker, Thomas
T1  - 3D-Spektroskopie hintergrundkontaminierter Einzelobjekte in Galaxien der lokalen Gruppe
Y1  - 2001
ER  - 
TY  - JOUR
A1  - Bergstedt, Christel
A1  - Horn, Martin Erik
A1  - Michelskis, Helmut
A1  - Winter, Rolf
T1  - Energie
JF  - Naturwissenschaften : Biologie, Chemie, Physik
Y1  - 2001
SN  - 3-06-020935-9
VL  - 8
PB  - Volk-und-Wissen-Verl.
CY  - Berlin
ER  -