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101.
Let X be a complex Banach space, and let
be the space of bounded operators on X. Given
and x ∈ X, denote by σT (x) the local spectrum of T at x.
We prove that if
is an additive map such that
then Φ (T) = T for all
We also investigate several extensions of this result to the case of
where
The proof is based on elementary considerations in local spectral theory, together with the following local identity principle:
given
and x ∈X, if σS+R (x) = σT+R (x) for all rank one operators
then Sx = Tx . 相似文献
102.
103.
Boujemâa Achchab Abdellatif Agouzal Khalid Bouihat Adil Majdoubi Ali Souissi 《Numerical Methods for Partial Differential Equations》2017,33(1):218-240
In this article we study a projection‐stabilized nonconforming finite element discretization of the Stokes problem. We present a priori error analysis and give a recovery‐based a posteriori error estimator for the considered problem. Numerical results illustrate the theoretical performance of the error estimator. © 2016 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 33: 218–240, 2017 相似文献
104.
Abdellatif Bourhim Stanislas Czernecki Pierre Krausz 《Journal of carbohydrate chemistry》2013,32(7):853-863
Abstract Under mild conditions, treatment of unprotected methyl-α-D-glucopyranoside, N-acetylglucosamine and maltose with triphenylphosphine, diethylazodicarboxylate and equimolar amount of various carboxylic acids allowed regioselective 6-O-esterifications (6′-O for maltose) of the carbohydrate without esterification of other hydroxyl groups. This reaction found an application in the synthesis of liposoluble, labelled sugars and hydrosoluble polymers. 相似文献
105.
The reaction of N 1-substituted-5-amino-4-cyanopyrazoles with malononitrile and diethylmalonate occurs with formation of 6-substituted pyrazolo[3,4-d]pyrimidines, and pyrazolo[3,4-b]pyridines respectively. The structures of the products and conceivable mechanisms are discussed. 相似文献
106.
Mariam A. Al‐Shiekh Abdellatif M. Salah El‐Din Ebtisam A. Hafez Mohamed H. Elnagdi 《Journal of heterocyclic chemistry》2004,41(5):647-654
A novel synthesis of arylpyrazole, isoxazole, dialkyl 1,6‐dihydropyridazine 5,6‐dicarboxylate derivatives and a new one‐step synthesis of azolopyrimidines under microwave‐assisted conditions are reported. 相似文献
107.
108.
The first access to dissymmetric 2,4-di(het)aryl-pyrido[3,2-d]pyrimidines III is reported. Two mild alternative routes led to the rarely targeted compounds from 2,4-dichloro- and 2-chloro-4-isopropylsulfanyl-pyrido[3,2-d]pyrimidine by two successive palladium-catalyzed reactions involving an original regioselective chlorine discrimination. Alternatively, type III compounds were elaborated from 2 by C-2 chlorine further displacement of the C-4 isopropylsulfanyl group, which acted as a temporary C-4 protecting group. These results open the way to innovative synthesis strategies of various bis-functionalized pyrimidine series. 相似文献
109.
Lopez N Zhao H Prosvirin AV Chouai A Shatruk M Dunbar KR 《Chemical communications (Cambridge, England)》2007,(44):4611-4613
Removal of methanol molecules from the interstices of a metal-organic framework based on a 2-D hexagonal Mn(II)-TCNQF(4) net results in stronger magnetic interactions and leads to a glassy magnetically ordered state; the magnetic behavior can be reversibly cycled upon solvation-desolvation of the material. 相似文献
110.
Using the decomposition method, we present in this paper constructions of multiresolution analyses on a compact Riemannian manifold M of dimension n(n∈N). These analyses are generated by a finite number of basic functions and are adapted to the study of the Sobolev spaces H1(M) and . 相似文献