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131.
In this paper we first develop a theory of almost automorphic
functions with values in Frechet spaces. Then, we consider the
semilinear differential equation x'(t) = A x(t) + f(t, x(t)), t ∈ ℝ in a Frechet space X, where A is the infinitesimal generator
of a C0-semigroup satisfying some conditions of exponential stability. Under suitable conditions on f, we prove the existence and
uniqueness of an almost automorphic mild solution to the equation. 相似文献
132.
Sorin Marculescu 《Nuclear Physics B》1983,213(3):523-544
A method for regularizing the supercurrent, preserving both gauge invariance and supersymmetry is developed, using point-splitting regularization and path-dependent phase factors in superspace. The supercurrent anomaly for general non-abelian supersymmetric theories is obtained on the mass-shell in the one-loop approximation. 相似文献
133.
134.
The EPR method has been used to study mechanically activated periclase powders. The Mn2+ and Cr3+ spectra in MgO depend on the number of defects. The lines broaden to a degree which depends on the nuclear spin; the ratio between the hyperfine components changes; the line shape changes from Lorentzian to a convoluted form; and the relative intensity of the forbidden transitions in the Mn2+ changes.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, Vol. 12, No. 3, pp. 48–52, March, 1969. 相似文献
135.
136.
We prove several unique prime factorization results for tensor products of type II1 factors coming from groups that can be realized either as subgroups of hyperbolic groups or as discrete subgroups of connected Lie groups of real rank 1. In particular, we show that if
is isomorphic to a subfactor in
, for some 2ri,sj, then mn. Mathematics Subject Classification (2000) Primary 46L10; Secondary 20F67 相似文献
137.
We study the nonlinear rheological behavior and the microscopic particle dynamics for a colloidal glass, to see whether recently developed models for driven glassy systems can be applied to predict the rheology. Qualitatively, all the findings predicted by the models can be retrieved in our system. Notably, the viscosity decreases strongly with the shear rate. Since it is difficult to predict non-Newtonian viscosities of colloidal systems due to long-ranged hydrodynamic interactions, this shows the promise of this approach for predicting flow behavior. In addition, the measurements allow us to relate the microscopic diffusion dynamics to the macroscopic viscosity of the system. 相似文献
138.
We prove that the moduli space A
11
lev
of (1,11)-polarized Abelian surfaces with level structure of canonical type is birational to Klein's cubic hypersurface in P
4
. Therefore, A
11
lev
is unirational but not rational, and there are no 11-cusp forms of weight 3. The same methods also provide an easy proof of the rationality of A
9
lev
. 相似文献
139.
Detonation diffraction through different geometries 总被引:1,自引:0,他引:1
We performed the study of the diffraction of a self-sustained detonation from a cylindrical tube (of inner diameter d) through different geometric configurations in order to characterise the transmission processes and to quantify the transmission
criteria to the reception chamber. For the diffraction from a tube to the open space the transmission criteria is expressed
by d
c
= k
c
·λ (with λ the detonation cell size and k
c
depending on the mixture and on the operture configuration, classically 13 for alkane mixtures with oxygen). The studied
geometries are: (a) a sharp increase of diameter (D/d > 1) with and without a central obstacle in the diffracting section, (b) a conical divergent with a central obstacle in the
diffracting section and (c) an inversed intermediate one end closed tube insuring a double reflection before a final diffraction
between the initiator tube and the reception chamber. The results for case A show that the reinitiation process depends on
the ratio d/λ. For ratios below k
c
the re-ignition takes place at the receptor tube wall and at a fixed distance from the step, i.e. closely after the diffracted
shock reflection shows a Mach stem configuration. For ratios below a limit ratio k
lim (which depends on D/d) the re-ignition distance increases with the decrease of d/λ. For both case A and B the introduction of a central obstacle (of blockage ratio BR = 0.5) at the exit of the initiator
tube decreases the critical transmission ratio k
c
by 50%. The results in configuration C show that the re-ignition process depends both on d/λ and the geometric conditions. Optimal configuration is found that provides the transmission through the two successive reflections
(from d = 26 mm to D
ch = 200 mm) at as small d/λ as 2.2 whatever the intermediate diameter D is. This configuration provides a significant improvement in the detonation transmission conditions.
This paper was based on work that was partly presented at the International Conference on Combustion and Detonation, Zel’dovich Memorial II, Moscow, Russia, 30 August–3 September 2004, and at the 20th International Colloquium on the Dynamics of Explosions and Reactive systems, Montreal, Canada, 31 July–5 August 2005. 相似文献
This paper was based on work that was partly presented at the International Conference on Combustion and Detonation, Zel’dovich Memorial II, Moscow, Russia, 30 August–3 September 2004, and at the 20th International Colloquium on the Dynamics of Explosions and Reactive systems, Montreal, Canada, 31 July–5 August 2005. 相似文献
140.
This Letter investigates all-optical magnetization switching from micromagnetic perspective. The influence of circularly polarized light on a magnetic sample was considered to be both directly through the inverse Faraday effect and indirectly aided by thermal induced effects by the laser beam. Dependence of all-optical switching on pulse duration, laser intensity and the magneto-optical susceptibility strength is studied. An important aspect of this investigation is the analysis of how the cooling process influences the successive switches, especially through limiting the successive writing time. 相似文献