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91.
Let X be an algebraic variety defined over a field of characteristic zero, and let ξMax_mult(X) be a point in the closed subset of maximum multiplicity of X. We provide a criterion, given in terms of arcs, to determine whether ξ is isolated in Max_mult(X). More precisely, we use invariants of arcs derived from the Nash multiplicity sequence to characterize when ξ is an isolated point in Max_mult(X).  相似文献   
92.
The work strengthens the result established by L. Cohen on uncertainty principle involving phase derivative. We propose stronger uncertainty principles not only in the classical setting for Fourier transform, but also for self-adjoint operators. We also deduce the conditions that give rise to the equal relation of the uncertainty principle. Examples are provided to show that the new uncertainty principle is truly sharper than the existing ones in literature.  相似文献   
93.
The Goursat formula for the hypergeometric function extends the Euler–Gauss relation to the case of logarithmic singularities.  相似文献   
94.
Seven three dimensional (3D) uranyl organic frameworks (UOFs), formulated as [NH4][(UO2)3(HTTDS)(H2O)] ( 1 ), [(UO2)4(HTTDS)2](HIM)6 ( 2 , IM=imidazole), [(UO2)4(TTDS)(H2O)2(Phen)2] ( 3 , Phen=1,10-phenanthroline), [Zn(H2O)4]0.5[(UO2)3(HTTDS)(H2O)4] ( 4 ), and {(UO2)2[Zn(H2O)3]2(TTDS)} ( 5 ), {Zn(UO2)2(H2O)(Dib)0.5(HDib)(HTTDS)} ( 6 , Dib=1,4-di(1H-imidazol-1-yl)benzene) and [Na]{(UO2)4[Cu3(u3-OH)(H2O)7](TTDS)2} ( 7 ) have been hydrothermally prepared using a rigid octadentate carboxylate ligand, tetrakis(3,5-dicarboxyphenyl)silicon(H8TTDS). These UOFs have different 3D self-assembled structures as a function of co-ligands, structure-directing agents and transition metals. The structure of 1 has an infinite ribbon formed by the UO7 pentagonal bipyramid bridged by carboxylate groups. With further introduction of auxiliary N-donor ligands, different structure of 2 and 3 are formed, in 2 the imidazole serves as space filler, while in 3 the Phen are bound to [UO2]2+ units as co-ligands. The second metal centers were introduced in the syntheses of 4–7 , and in all cases, they are part of the final structures, either as a counterion ( 4 ) or as a component of framework ( 5 − 7 ). Interesting, in 7 , a rare polyoxometalate [Cu33-OH)O7(O2CR)4] cluster was found in the structure. It acts as an inorganic building unit together with the dimer [(UO2)2(O2CR)4] unit. Those uranyl carboxylates were sufficiently determined by single crystal X-ray diffraction, and their topological structures and luminescence properties were analyzed in detail.  相似文献   
95.
Abstract

We have already reported the results of direct observations of electron-topological phase transition (ETT) in cadmium'. The appearance of new dHvA-frequencies corresponding to the Fermi surface (FS) change, i.e. restoring of folding of hole “monster” and electron “needle” appearance is observed under pressure. In t h i s report we are going to enlarge on the ETT consequences study in cadmium-on the advent of anomalous electronic features in transverse magnetoresistance and thermoelectric power.  相似文献   
96.
Classical Taylor expansions of holomorphic functions in the complex plane are extended to distributions in Rnand in domains  相似文献   
97.
98.
In this paper, we consider the inviscid 3D Boussinesq system in Besov spaces and obtain the lower bound for the lifespan of solutions.  相似文献   
99.
The interior C γ, γ/2-regularity for the first gradient with respect to the space variables of a weak solution to a class of nonlinear second order parabolic systems is proven under the assumption that oscillations of coefficients are controlled by the ellipticity constant.  相似文献   
100.
In this paper we study the family of embeddings Φt of a compact RCD?(K,N) space (X,d,m) into L2(X,m) via eigenmaps. Extending part of the classical results [10], [11] known for closed Riemannian manifolds, we prove convergence as t0 of the rescaled pull-back metrics Φt?gL2 in L2(X,m) induced by Φt. Moreover we discuss the behavior of Φt?gL2 with respect to measured Gromov-Hausdorff convergence and t. Applications include the quantitative Lp-convergence in the noncollapsed setting for all p<, a result new even for closed Riemannian manifolds and Alexandrov spaces.  相似文献   
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