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In this paper we give the conditions on the pair (ω 1, ω 2) which ensures the boundedness of the anisotropic maximal operator and anisotropic singular integral operators from one generalized Morrey space Mp,w1 \mathcal{M}_{p,\omega _1 } to another Mp,w2 \mathcal{M}_{p,\omega _2 }, 1 < p < g8, and from the space M1,w1 \mathcal{M}_{1,\omega _1 } to the weak space WM1,w2 W\mathcal{M}_{1,\omega _2 }.  相似文献   
3.
Let T={T(t)}t?0 be a bounded C0-semigroup on a Banach space with generator A. We define AT as the closure with respect to the operator-norm topology of the set {f?(T):fL1(R+)}, where f?(T)=0f(t)T(t)dt is the Laplace transform of fL1(R+) with respect to the semigroup T. Then AT is a commutative Banach algebra. It is shown that if the unitary spectrum σ(A)iR of A is at most countable, then the Gelfand transform of SAT vanishes on σ(A)iR if and only if, limt6T(t)S6=0. Some applications to the semisimplicity problem are given. To cite this article: H. Mustafayev, C. R. Acad. Sci. Paris, Ser. I 342 (2006).  相似文献   
4.
In the context of phenomenological models in which the soft supersymmetry-breaking parameters of the MSSM become universal at some unification scale, M in, above the GUT scale, M GUT, it is possible that all the scalar mass parameters m 0, the trilinear couplings A 0 and the bilinear Higgs coupling B 0 vanish simultaneously, as in no-scale supergravity. Using these no-scale inputs in a renormalisation-group analysis of the minimal supersymmetric SU(5) GUT model, we pay careful attention to the matching of parameters at the GUT scale. We delineate the region of M in, m 1/2 and tan?β where the resurrection of no-scale supergravity is possible, taking due account of the relevant phenomenological constraints such as electroweak symmetry breaking, m h ,bs γ, the neutralino cold dark matter density Ω χ h 2 and g μ ?2. No-scale supergravity survives in an L-shaped strip of parameter space, with one side having m 1/2?200 GeV, the second (orthogonal) side having M in?5×1016 GeV. Depending on the relative signs and magnitudes of the GUT superpotential couplings, these may be connected to form a triangle whose third side is a hypotenuse at larger M in, m 1/2 and tan?β, whose presence and location depend on the GUT superpotential parameters. We compare the prospects for detecting sparticles at the LHC in no-scale supergravity with those in the CMSSM and the NUHM.  相似文献   
5.
Nucleolytic activities of some new oxime-type ligand complexes were investigated by neutral agarose gel electrophoresis. Analysis of the cleavage products in agarose gel indicated that all complexes used converted supercoiled pUC18 plasmid DNA to its nicked or linear form. It was found that nucleolytic activities of the complexes depend on the complex concentration, reaction time and the presence of a cooxidant (magnesium monoperoxyphthalate, MMPP) in the reaction mixture. However, the complexes cleaved pUC18 plasmid DNA at all investigated pH values. Nucleolytic activities of complexes were investigated for different complex concentrations (0.1–100 μmol L−1), pH values (6.0–10.0) and reaction times (0–60 min). Molecular modeling studies performed by the Hyperchem Software together with DNA-binding studies showed that planar sites of the complexes intercalated into double stranded DNA. It can be concluded that all oxime-type ligand complexes used can be evaluated as nuclease mimics.  相似文献   
6.
Two polymeric complexes of glicyne with manganese(II) have been prepared and characterized by means of spectroscopic and x-ray analyses. The first complex of the formula [Mn(Gly)Cl2(H2O)2] crystallizes in the monoclinic space group P21/n with a = 6.519(2), b = 15.981(3), c = 7.893(2) Å, and = 97.18(3)°. The Mn atoms are in distorted octahedral environments with all ligands in cis positions. The adjacent manganese(II) ions are linked in polymeric chains via carboxylate groups. The second complex [Mn(Gly)2Cl2] crystallizes in the triclinic space group P with a = 4.968(2), b = 6.582(2), c = 7.925(3) Å, = 106.17(3), = 92.86(3), and = 107.21(3)°. The octahedral-coordinated manganese(II) ion is situated on a crystallographic center of symmetry and is bound to four carboxylate oxygen atoms from different glicyne molecules and two chloride ions.  相似文献   
7.
We investigate, both theoretically and experimentally, dipolar relaxation in a gas of magnetically trapped chromium atoms. We find that the large magnetic moment of 6B results in an event rate coefficient for dipolar relaxation processes of up to 3.2×10-11 cm3s-1 in a magnetic field of 44 G. We present a theoretical model based on pure dipolar coupling, which predicts dipolar relaxation rates that agree with our experimental observations. This very general approach can be applied to a large variety of dipolar gases. PACS 34.50.-s; 34.50.PI; 03.65.NK; 32.80.PJ  相似文献   
8.
In this paper, the boundedness of a large class of sublinear commutator operators T b generated by a Calderón-Zygmund type operator on a generalized weighted Morrey spaces \({M_{p,\varphi }}(w)\) with the weight function w belonging to Muckenhoupt’s class A p is studied. When 1 < p < ∞ and b ∈ BMO, sufficient conditions on the pair (φ 1, φ 2) which ensure the boundedness of the operator T b from \({M_{p,\varphi 1}}(w)\) to \({M_{p,\varphi 2}}(w)\) are found. In all cases the conditions for the boundedness of T b are given in terms of Zygmund-type integral inequalities on (φ 1, φ 2), which do not require any assumption on monotonicity of φ 1(x, r), φ 2(x, r) in r. Then these results are applied to several particular operators such as the pseudo-differential operators, Littlewood-Paley operator, Marcinkiewicz operator and Bochner-Riesz operator.  相似文献   
9.
In this paper, characterizations of the embeddings between weighted Copson function spaces \(Co{p_{{p_1},{q_1}}}\left( {{u_1},{v_1}} \right)\) and weighted Cesàro function spaces \(Ce{s_{{p_2},{q_2}}}\left( {{u_2},{v_2}} \right)\) are given. In particular, two-sided estimates of the optimal constant c in the inequality
$${\left( {\int_0^\infty {{{\left( {\int_0^t {f{{\left( \tau \right)}^{{p_2}}}{v_2}\left( \tau \right)d\tau } } \right)}^{{q_2}/{p_2}}}{u_2}\left( t \right)dt} } \right)^{1/{q_2}}} \leqslant c{\left( {\int_0^\infty {{{\left( {\int_t^\infty {f{{\left( \tau \right)}^{{p_1}}}{v_1}\left( \tau \right)d\tau } } \right)}^{{q_1}/{p_1}}}{u_1}\left( t \right)dt} } \right)^{1/{q_1}}},$$
where p1, p2, q1, q2 ∈ (0,∞), p2q2 and u1, u2, v1, v2 are weights on (0,∞), are obtained. The most innovative part consists of the fact that possibly different parameters p1 and p2 and possibly different inner weights v1 and v2 are allowed. The proof is based on the combination of duality techniques with estimates of optimal constants of the embeddings between weighted Cesàro and Copson spaces and weighted Lebesgue spaces, which reduce the problem to the solutions of iterated Hardy-type inequalities.
  相似文献   
10.
We prove the thermodynamic equivalence of the Dicke two-level model and a van der Waals spin system. This serves to show that there are cases where the Wang-Hioe procedure and the Power-Zienau transformation may be applied in any order.  相似文献   
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