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991.
LetQ n β be the law of then-step random walk on ?d obtained by weighting simple random walk with a factore ?β for every self-intersection (Domb-Joyce model of “soft polymers”). It was proved by Greven and den Hollander (1993) that ind=1 and for every β∈(0, ∞) there exist θ*(β)∈(0,1) and such that under the lawQ n β asn→∞: $$\begin{array}{l} (i) \theta ^* (\beta ) is the \lim it empirical speed of the random walk; \\ (ii) \mu _\beta ^* is the limit empirical distribution of the local times. \\ \end{array}$$ A representation was given forθ *(β) andµ β β in terms of a largest eigenvalue problem for a certain family of ? x ? matrices. In the present paper we use this representation to prove the following scaling result as β?0: $$\begin{array}{l} (i) \beta ^{ - {\textstyle{1 \over 3}}} \theta ^* (\beta ) \to b^* ; \\ (ii) \beta ^{ - {\textstyle{1 \over 3}}} \mu _\beta ^* \left( {\left\lceil { \cdot \beta ^{ - {\textstyle{1 \over 3}}} } \right\rceil } \right) \to ^{L^1 } \eta ^* ( \cdot ) . \\ \end{array}$$ The limitsb *∈(0, ∞) and are identified in terms of a Sturm-Liouville problem, which turns out to have several interesting properties. The techniques that are used in the proof are functional analytic and revolve around the notion of epi-convergence of functionals onL 2(?+). Our scaling result shows that the speed of soft polymers ind=1 is not right-differentiable at β=0, which precludes expansion techniques that have been used successfully ind≧5 (Hara and Slade (1992a, b)). In simulations the scaling limit is seen for β≦10?2. 相似文献
992.
Frobenius manifolds (solutions of WDVV equations) in canonical coordinates are determined by the system of Darboux–Egoroff
equations. This system of partial differential equations appears as a specific subset of the n-component KP hierarchy. KP representation theory and the related Sato infinite Grassmannian are used to construct solutions
of this Darboux–Egoroff system and the related Frobenius manifolds. Finally we show that for these solutions Dubrovin's isomonodromy
tau-function can be expressed in the KP tau-function.
Received: 1 September 1998 / Accepted: 7 March 1999 相似文献
993.
J. W. Niemantsverdriet J. Van Grondelle A. M. Van der Kraan 《Hyperfine Interactions》1988,41(1):677-680
Bimetallic FePd/SiO2 catalysts exhibit higher activities in the formation of methanol from synthesis gas than Pd/SiO2. The catalysts are a complex mixture of bcc and fcc FePd alloy, α-Fe and some unreduced iron. 相似文献
994.
995.
M. Adamus N. M. Agababyan I. V. Ajinenko Yu. A. Belokopytov H. Bia?kowska H. B?ttcher P. V. Chliapnikov F. Crijns A. De Roeck E. A. De Wolf K. Dziunikowska A. M. F. Endler W. Friebel H. Graessler P. van Hal J. K. Karamyan D. Kisielewska W. Kittel A. I. Kurnosenko B. B. Levchenko F. Meijers M. Merk A. B. Micha?owska V. I. Nikolaenko L. C. S. Oliveira K. Olkiewicz V. M. Ronjin A. M. Rybin H. M. T. Saarikko Y. T. M. Saarikko W. Schmitz L. Scholten N. A. Sotnikova J. Stepaniak O. G. Tchikilev L. A. Tikhonova V. A. Uvarov F. Verbeure R. Wischnewski EHS/NA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1988,37(2):215-229
The charged particle multiplicity distribution has been studied for non-single-diffractive π+ p andpp collisions at \(\sqrt s = 22\) GeV, for full phase space as well as for intervals in rapidity, azimuthal angle and transverse momentum. In general, the multiplicity distribution is well described by a negative binomial. From comparison of the distribution for negative or positive particles to that of all charged particles, cascading is favoured as an interpretation over stimulated emission. Interesting consequences follow from a comparison of our results to those at collider energies and toe + e ? data at comparable energy. Furthermore, evidence is given that the multiplicity distribution is not exactly of negative binomial type in every (connected or disconnected) phase space region. 相似文献
996.
van den Brand JF Ent R Anthony PL Arnold RG Arrington J Beise EJ Belz JE Bosted PE Bulten H Chapman MS Coulter KP Dietrich FS Epstein M Filippone BW Gao H Gearhart RA Geesaman DF Hansen J Holt RJ Jackson HE Jones CE Keppel CE Kinney ER Kuhn S Lee K Lorenzon W Lung A Makins NC Margaziotis DJ McKeown RD Milner RG Mueller B Napolitano J Nelson J O'Neill TG Papavassiliou V Petratos GG Potterveld DH Rock SE Spengos M Szalata ZM Tao LH van Bibber K Wasson DA White JL Zeidman B 《Physical review D: Particles and fields》1995,52(9):4868-4871
997.
998.
999.
In this paper the analysis of the TSEE curves of MgO is presented and two methods of the calculations of the activation energy and the frequency factor of the TSEE peaks of MgO are compared. There is good agreement concerning the activation energy of the trapping centres between the least squares method for the fitting of experimental and theoretical curves and the universal calculation method developed by de Muer. 相似文献
1000.
B. Bader P. Heitjans H. Ackermann P. Freilnder G. Kiese A. Schirmer H.-J. Stckmann C. van der Marel 《Annalen der Physik》1985,497(2):169-174
The method of β-radiation detected nuclear magnetic resonance (β-NMR) was applied to 8Li in a 7Li3N single crystal. From NMR signals and spin-lattice relaxation rates the activation enthalpies for two distinct Li+ diffusion processes were deduced. Ultraslow diffusion corresponding to ionic jump rates down to 0.1 s?1 was observed. It could be confirmed that the static electric field gradients at the two inequivalent Li sites have opposite signs. 相似文献