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11.
Oscar Valero 《Proceedings Mathematical Sciences》2006,116(2):175-191
Given a normed cone (X, p) and a subconeY, we construct and study the quotient normed cone (X/Y,p) generated byY. In particular we characterize the bicompleteness of (X/Y, ‖·‖
p
,p) in terms of the bicompleteness of (X, p), and prove that the dual quotient cone ((X/Y)*, || · ‖·‖p,p) can be identified as a distinguished subcone of the dual cone (X
*, || · ||p, u). Furthermore, some parts of the theory are presented in the general setting of the spaceCL(X, Y) of all continuous linear mappings from a normed cone (X, p) to a normed cone (Y, q), extending several well-known results related to open continuous linear mappings between normed linear spaces. 相似文献
12.
Inés CarrancoJosé Luis D?&#x;az Oscar JiménezRodolfo Lavilla 《Tetrahedron letters》2003,44(46):8449-8452
The Lewis acid-catalyzed interaction of dihydropyridines with ethyl glyoxalate and primary aliphatic amines yields, depending on the reaction conditions, bicyclic aminals or rearranged tetrahydropyridines in one-pot multicomponent reactions. 相似文献
13.
Mathematische Annalen - 相似文献
14.
Let be a bounded, connected linearly convex set in with boundary. We show that the maximal ideal (both in ) and ) consisting of all functions vanishing at is generated by the coordinate functions .
Received: 2 July 2001; in final form: 26 September 2001 / Published online: 28 February 2002 相似文献
15.
Rastislav Varga Arcady Zhukov Michail Ipatov Juan Maria Blanco Julian Gonzalez Valentina Zhukova Pavol Vojtanik 《Journal of magnetism and magnetic materials》2006
The effect of the glass coating on the single domain wall potential in amorphous glass-coated Fe-based microwire has been studied by the switching field distribution technique. The thermoactivated mechanism model is used to describe the thermally activated switching through the complex energy barrier in amorphous FeSiB microwires. Glass removal leads to the increase of the probability of the thermally activated switching pointing to the decrease of the energy barrier. 相似文献
16.
Commutators of singular integrals on spaces of homogeneous type 总被引:1,自引:0,他引:1
In this work we prove some sharp weighted inequalities on spaces of homogeneous type for the higher order commutators of singular
integrals introduced by R. Coifman, R. Rochberg and G. Weiss in Factorization theorems for Hardy spaces in several variables,
Ann. Math. 103 (1976), 611–635. As a corollary, we obtain that these operators are bounded on L
p
(w) when w belongs to the Muckenhoupt’s class A
p
, p > 1. In addition, as an important tool in order to get our main result, we prove a weighted Fefferman-Stein type inequality
on spaces of homogeneous type, which we have not found previously in the literature. 相似文献
17.
18.
Christo I. Ivanov Nikolai Tyutyulkov Gottfried Olbrich H. Barentzen Oscar E. Polansky 《Theoretical chemistry accounts》1988,73(1):27-42
Utilizing an extended Hubbard-type Hamiltonian which incorporates both nearest-neighbour Coulomb repulsion and exchange interactions, we have studied the energy dispersion of the lowest elementary excitation from the ferromagnetically aligned state of quasi one-dimensional alternant hydrocarbon networks. It was found that the main effect of the long range Coulomb interaction may be thought of as a renormalization (screening) of the on-site Hubbard integral. This implies an enhancement of the kinetic exchange term and impairs the stability of the ferromagnetic state towards single spin inversions. However, for physically relevant values of the parameters entering the model Hamiltonian, the collective spin excitation represents a magnon, whose energy band lies above the reference value pertaining to the magnetically saturated configuration.Dedicated to Prof. Dr. Adolf Neckel on the occasion of his 60th birthday 相似文献
19.
Oscar E. Piro Eduardo E. Castellano Roberto C. V. Piatti Agustín E. Bolzn Alejandro J. Arvia 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(4):m252-m255
The crystal structures of two salts of bis(thiourea)gold(I) complexes, namely bis(thiourea‐κS)gold(I) chloride, [Au(CH4N2S)2]Cl, (I), and bis[bis(thiourea‐κS)gold(I)] sulfate, [Au(CH4N2S)2]2SO4, (II), have been determined. The chloride salt, (I), is isomorphous with the corresponding bromide salt, although there are differences in the bonding. The AuI ion is located on an inversion centre and coordinated by two symmetry‐related thiourea ligands through the lone pairs on their S atoms [Au—S 2.278 (2) Å and Au—S—C 105.3 (2)°]. The sulfate salt, (II), crystallizes with four independent [Au(CH4N2S)2]+ cations per asymmetric unit, all with nearly linear S—Au—S bonding. The cations in (II) have similar conformations to that found for (I). The Au—S distances range from 2.276 (3) to 2.287 (3) Å and the Au—S—C angles from 173.5 (1) to 177.7 (1)°. These data are relevant in interpreting different electrochemical processes where gold–thiourea species are formed. 相似文献
20.
On the basis of Altona's empirical generalization of the Karplus equation, an expression of 3JH,H as function of pseudorotation parameters for five-membered rings, was deduced. The resulting equation was parametrized by means of molecular mechanics calculations for tetrahydrofuran and tetrahydrothiophene. Estimation of 3JH,H for the full pseudorotational itinerary was made. From the best fit between calculated and measured 3JH,H values the preferred conformation of those rings may be established. The procedure was applied for the conformational analysis of 4-thiohexofuranose derivatives, having and β,
-galacto and D- manno, and -
-talo configurations. 相似文献