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991.
992.
David Ruelle 《Communications in Mathematical Physics》2007,270(1):233-265
We analyze the dynamics of a simple but nontrivial classical Hamiltonian system of infinitely many coupled rotators. We assume
that this infinite system is driven out of thermal equilibrium either because energy is injected by an external force (Case
I), or because heat flows between two thermostats at different temperatures (Case II). We discuss several possible definitions
of the entropy production associated with a finite or infinite region, or with a partition of the system into a finite number
of pieces. We show that these definitions satisfy the expected bounds in terms of thermostat temperatures and energy flow. 相似文献
993.
A photoemission study of molybdenum hexacarbonyl adsorption and decomposition on TiO2(1 1 0) surface
The adsorption and decomposition of molybdenum hexacarbonyl on (1 1 0) TiO2 surfaces were studied using both core levels and valence band photoemission spectroscopies. It was found that after an adsorption at 140 K, when going back to room temperature, only a small part of molybdenum compounds, previously present at low temperature, remained on the TiO2 surface. This indicates that the desorption temperature on such a surface is lower than the decomposition one. The use of photon irradiation to decompose the hexacarbonyl molecule was also studied. It was shown that during such a decomposition molecular fragments were chemisorbed on the surface allowing a higher amount of metal to remain on the surface. It was also shown that it was possible to get rid of adsorbed subcarbonyl groups and to organize the metal atoms by thermal treatments at temperatures as low as 400 K, i.e. much lower than the one needed to obtain the same structures using physical vapour deposition (PVD). Moreover, due to lower used temperatures, this chemical way of deposition allows a better control of the interface than during PVD growth. 相似文献
994.
Xu Cheng 《Mathematische Annalen》2003,325(2):229-248
Let M be a 2m-dimensional compact Riemannian manifold with Anosov geodesic flow. We prove that every closed bounded k form, k≥2, on the universal covering of M is d(bounded). Further, if M is homotopy equivalent to a compact K?hler manifold, then its Euler number χ(M) satisfies (−1)
m
χ(M)>0.
Received: 25 September 2001 / Published Online: 16 October 2002 相似文献
995.
996.
Anindya Datta 《Pramana》2003,60(2):363-368
We propose a novel method for the search of supersymmetry, especially for the electroweak gauginos at the large hadron collider
(LHC). Gauge boson fusion technique was shown to be useful for heavy and intermediate mass Higgs bosons. In this article,
we have shown that this method can also be applied to find the signals of EW gauginos in supersymmetric theories where the
canonical search strategies for these particles fail. 相似文献
997.
We isolate several classes of stationary sets of [k]ωand investigate implications among them. Under a large cardinal assumption, we prove a structure theorem for stationary sets. 相似文献
998.
This article focuses on discontinuous Galerkin method for the two‐ or three‐dimensional stationary incompressible Navier‐Stokes equations. The velocity field is approximated by discontinuous locally solenoidal finite element, and the pressure is approximated by the standard conforming finite element. Then, superconvergence of nonconforming finite element approximations is applied by using least‐squares surface fitting for the stationary Navier‐Stokes equations. The method ameliorates the two noticeable disadvantages about the given finite element pair. Finally, the superconvergence result is provided under some regular assumptions. © 2006 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 23: 421–436, 2007 相似文献
999.
Li Lin 《Annals of Differential Equations》2007,23(4):433-439
In this paper,we study some permanence and global stability to a nonau- tonomous nonlinear discrete single species system,and obtain some sufficient condition of global stability to the system. 相似文献
1000.
In this paper, the notion of gap functions is extended from scalar case to vector one. Then, gap functions and generalized
functions for several kinds of vector equilibrium problems are shown. As an application, the dual problem of a class of optimization
problems with a system of vector equilibrium constraints (in short, OP) is established, the concavity of the dual function,
the weak duality of (OP) and the saddle point sufficient condition are derived by using generalized gap functions.
This work was supported by the National Natural Science Foundation of China (10671135) and the Applied Research Project of
Sichuan Province (05JY029-009-1). 相似文献