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111.
Elisabeth-Jeanne Popovici Mihail Nazarov Laura Muresan Do Young Noh Marius Morar Ecaterina Bica Emil Indrea 《Radiation measurements》2010,45(3-6):300-303
Terbium activated yttrium niobium tantalate phosphors were prepared by solid-state reaction and were characterized by photoluminescence measurements, X-ray diffraction and scanning electron microscopy. Photoluminescence (PL) of Y0.95Tb0.05Ta1?xNbxO4 phosphors (x = 0–1) are influenced by the host-lattice composition, degree of crystalline order and particle morphology and size. The effect of the morpho-structural properties on PL characteristics of Y(Ta,Nb)O4:Tb powders is reported. 相似文献
112.
We study the Dirichlet and Neumann boundary value problems for the Laplacian in a Lipschitz domain ${\Omega}$ , with boundary data in the Besov space ${B_{s}^{p,p} (\partial\Omega).}$ The novelty is to identify a way of measuring smoothness for the solution u that allows us to consider the case p < 1. This is accomplished by using a Besov-based nontangential maximal function in place of the classical one. This builds on the works of Jerison and Kenig [14], where the case p > 1 was treated. 相似文献
113.
Heteroepitaxy can involve materials with a misfit of crystal structure. Rotation domains in the epilayer are a fundamental consequence. We derive a general expression for their (minimum) number which is determined by the mismatch of the rotational symmetries of the substrate and epilayer. In the case of a mismatch of rotational symmetry, the number of rotation domains of material A on material B is different from that of B on A. A larger number of rotation domains can occur due to domain structure or nearly fulfilled additional symmetries of the substrate surface. 相似文献
114.
Marius Ghergu 《International Journal of Mathematical Education in Science & Technology》2018,49(5):802-807
We explore the connection between the notion of critical point for a function of one variable and various inequalities for iterated exponentials defined on the positive semiline of real numbers. 相似文献
115.
Global analysis of the shadow Gierer-Meinhardt system with general linear boundary conditions in a random environment
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Kwadwo Antwi-Fordjour Seonguk Kim Marius Nkashama 《Journal of Applied Analysis & Computation》2020,10(5):1980-1994
The global analysis of the shadow Gierer-Meinhardt system with multiplicative white noise and general linear boundary conditions is investigated in this paper.
For this reaction-diffusion system, we employ a fixed point argument to prove local existence and uniqueness. Our results on global existence are based on \emph{a priori} estimates of solutions. 相似文献
116.
We study the fully inhomogeneous Dirichlet problem for the Laplacian in bounded convex domains in Rn, when the size/smoothness of both the data and the solution are measured on scales of Besov and Triebel-Lizorkin spaces. As a preamble, we deal with the Dirichlet and Regularity problems for harmonic functions in convex domains, with optimal nontangential maximal function estimates. As a corollary, sharp estimates for the Green potential are obtained in a variety of contexts, including local Hardy spaces. A substantial part of this analysis applies to bounded semiconvex domains (i.e., Lipschitz domains satisfying a uniform exterior ball condition). 相似文献
117.
The dirichlet problem in lipschitz domains for higher order elliptic systems with rough coefficients
Vladimir. Maz’ya Marius Mitrea Tatyana Shaposhnikova 《Journal d'Analyse Mathématique》2010,110(1):167-239
We study the Dirichlet problem, in Lipschitz domains and with boundary data in Besov spaces, for divergence form strongly
elliptic systems of arbitrary order with bounded, complex-valued coefficients. A sharp corollary of our main solvability result
is that the operator of this problem performs an isomorphism between weighted Sobolev spaces when its coefficients and the
unit normal of the boundary belong to the space VMO. 相似文献
118.
Mark S. Ashbaugh Fritz Gesztesy Marius Mitrea Gerald Teschl 《Advances in Mathematics》2010,223(4):1372-885
We study spectral properties for HK,Ω, the Krein-von Neumann extension of the perturbed Laplacian −Δ+V defined on , where V is measurable, bounded and nonnegative, in a bounded open set Ω⊂Rn belonging to a class of nonsmooth domains which contains all convex domains, along with all domains of class C1,r, r>1/2. In particular, in the aforementioned context we establish the Weyl asymptotic formula
119.
Saturated models constitute one of the powerful methods of conventional model theory, with many applications. Here we develop
a categorical abstract model theoretic approach to saturated models within the theory of institutions. The most important
consequence is that the method of saturated models becomes thus available to a multitude of logical systems from logic or
from computing science. In this paper we define the concept of saturated model at an abstract institution-independent level
and develop the fundamental existence and uniqueness theorems. As an application we prove a general institution-independent
version of the Keisler–Shelah isomorphism theorem “any two elementarily equivalent models have isomorphic ultrapowers” (assuming
Generalized Continuum Hypothesis). 相似文献
120.
The aim of this article is twofold. On the one hand, we study the well-posedness of the Lamé system ${-\mu\Delta-\mu'\nabla{\rm div} }The aim of this article is twofold. On the one hand, we study the well-posedness of the Lamé system -mD-m¢?div{-\mu\Delta-\mu'\nabla{\rm div} } in L
q
(Ω), where Ω is an open subset of
\mathbbRn{{\mathbb{R}}^n} satisfying mild regularity assumptions and the Lamé moduli μ, μ′ are such that μ > 0 and μ + μ′ > 0. On the other hand, we prove the analyticity of the semigroup generated by the Lamé operator as well as the maximal
regularity property for the time-dependent Lamé system equipped with a homogeneous Dirichlet boundary condition based on off-diagonal
estimates. 相似文献