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11.
We extend a recent result of A. Jonsson about mutual absolute continuity of twoD s -measures on ans-setFR n to the homogeneous spaces (X, d, μ) of Coifman, Weiss. Here we define Hausdorff measure, Hausdorff dimension,D s -set andd-set relative to the measureμ. Our main result holds for so called (s, d)-sets,ds, and is stronger than Jonssons result even inR n . As applications we interpret this Hausdorff dimension as a relative dimension for very regular sets and show that it in general depends strongly onμ. For this purpose we construct a strictly increasing functionf :RR, whose measure is doubling and concentrated on a set of arbitrary small Hausdorff dimension. The extension off to a quasiconformal map of the half plane onto itself sharpens a classical example of Ahlfors-Beurling.  相似文献   
12.
The development of a fluorescent LCK inhibitor that exhibits favourable solvatochromic properties upon binding the kinase is described. Fluorescent properties were realised through the inclusion of a prodan‐derived fluorophore into the pharmacophore of an ATP‐competitive kinase inhibitor. Fluorescence titration experiments demonstrate the solvatochromic properties of the inhibitor, in which dramatic increase in emission intensity and hypsochromic shift in emission maxima are clearly observed upon binding LCK. Microscopy experiments in cellular contexts together with flow cytometry show that the fluorescence intensity of the inhibitor correlates with the LCK concentration. Furthermore, multiphoton microscopy experiments demonstrate both the rapid cellular uptake of the inhibitor and that the two‐photon cross section of the inhibitor is amenable for excitation at 700 nm.  相似文献   
13.
Using dispersion relations, we derive the complete virtual QED contributions to Bhabha scattering due to vacuum polarization effects. We apply our result to hadronic corrections and to heavy lepton and top quark loop insertions. We give the first complete estimate of their net numerical effects for both small and large angle scattering at typical beam energies of meson factories, the CERN Large Electron-Positron Collider, and the International Linear Collider. With a typical amount of 1-3 per mil they are of relevance for precision experiments.  相似文献   
14.
An effective two step synthesis of isobellendine, starting from tropinone, is described.  相似文献   
15.
A theorem of Beurling states that if f satisfies , n = 1, 2,..., for some 0 < ρ < 2, on a real interval I, then f is analytic in a rhombus containing I. We study the corresponding problem for the quantum differences Δ n f (q, x), q > 1, n = 1, 2,..., for functions defined on (0, ∞) and prove quantitative and qualitative analogues of Beurling’s result. We also characterize the analyticity of f on subintervals of (0, ∞) in q-analytic terms.  相似文献   
16.
A new type of electromagnetic soft magnetic material (SMM) is introduced, based on spherical iron powder particles and a suitable polymer binder. A key feature of this material is that it can be cast or molded into almost any 3D shape, hence the denotation soft magnetic moldable composite (SM2C). The SM2C is compared with a set of reference materials, such as ferrites, laminated steels, and soft magnetic composites, in terms of primary properties such as permeability and loss, and other properties, such as thermal conductivity and manufacturability. The SM2C has the obvious disadvantage of relatively low permeability, but offers benefits such as relatively low losses and high potential for close integration into electromagnetic circuits. Some recent SM2C applications are illustrated, and design and manufacturing aspects are discussed.  相似文献   
17.
Localized phonon modes in quench-condensed Pb.9In.1 films, annealed at several temperatures up to 300 K, were studied by the method of superconductive tunneling. No localized modes could be seen in very disordered films. Structure from such modes first appeared as the crystallite grains size increased. Work supported by the Swedish Natural Science Research Council.  相似文献   
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We consider real valued functions f defined on a subinterval I of the positive real axis and prove that if all of f’s quantum differences are nonnegative then f has a power series representation on I. Further, if the quantum differences have fixed sign on I then f is analytic on I.  相似文献   
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