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1.
Well-Posedness by Perturbations of Variational Problems 总被引:3,自引:0,他引:3
Lemaire B. Ould Ahmed Salem C. Revalski J. P. 《Journal of Optimization Theory and Applications》2002,115(2):345-368
In this paper, we consider the extension of the notion of well-posedness by perturbations, introduced by Zolezzi for optimization problems, to other related variational problems like inclusion problems and fixed-point problems. Then, we study the conditions under which there is equivalence of the well-posedness in the above sense between different problems. Relations with the so-called diagonal well-posedness are also given. Finally, an application to staircase iteration methods is presented. 相似文献
2.
This paper is concerned with the spectral analysis of a one-velocity transport operator with Maxwell boundary condition in
L
1-space. After a detailed spectral analysis it is shown that the associated Cauchy problem is governed by a C
0-semigroup. Next, we discuss the irreducibility of the transport semigroup. In particular, we show that the transport semigroup
is irreducible. Finally, a spectral decomposition of the solutions into an asymptotic term and a transient one which will
be estimated for smooth initial data is given. 相似文献
3.
A. F. Pronin J. Kovač R. Kada V. G. Kharchenko 《Chemistry of Heterocyclic Compounds》1979,15(12):1279-1283
The a complexes of furan, thiophene, pyrrole, pyridine, and benzene with the hydride ion were calculated by the MINDO/3 method. The affinities of the indicated aromatic rings and a number of substituted furans for the H– ion were estimated. It is shown that the relative magnitude of the affinity correlates qualitatively with the experimental data on the relative rates of the reaction of the examined compounds with nucleophilic reagents. The following order of increasing reactivities of unsubstituted aromatic rings was obtained: pyrrole相似文献
4.
Jarmila Štetinová Rudolf Kada Miloslava Dandárová Marcela Krublová Ján Leśko 《Chemistry of Heterocyclic Compounds》1995,31(10):1231-1233
Substituted ]-(6-methoxy-2-benzothiazolyt)-2-pyridones were prepared from 2-amino-6-methoxybenzathiazate through N-(6-methoxy-2-benzothiazotyl) cyanvorearmileaznd-3-aryl-N-(6-methoxy-2-benzothiazolyt)-2-cyano-2-propenamides. The cyclization of the latter with malonodinitrile in the presence of piperidine gave the corresponding pyridones. The structures of the synthesized compounds were confirmed by1H NMR and mass spectral data.Department of Organic Chemistry, Mass Spectrometry Laboratory, Slovak Technical University, 812 37 Bratislava, Slovakia. Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1402–1404, October, 1995. Original article submitted August 24, 1995. 相似文献
5.
6.
Abstract— The absorption and emission properties of the photochemically produced dipyrimidine adducts are analyzed at 300 and 77K. Those adducts which have a saturated C(5)—C(6) bond in the pyrimidin-2,4-dione (Pyr) ring and a pyrimidin-2-one (Pyo) ring behave spectroscopically as a substituted Pyo. However, those consisting of one Pyr and one Pyo moiety can be considered as bichromophoric molecules and their spectral properties can be understood in terms of the relative torsional angle between the two rings. The adduct with the most bulky substituents ortho to the torsional bond bears the largest torsional angle and exhibits relatively independent absorption and emission phenomenon. At the other extreme, those adducts with no substituents at this position exist as almost planar molecules and exhibit considerable overlap of absorption bands as well as room temperature fluorescence which, in certain cases, is characteristic of intramolecular exciplex interaction. Using inter-ring torsional angles of ortho-substituted biphenyl molecules as a basis for comparative calculation, quantitative estimates of the torsional angles in dipyrimidine adducts at 300K have been made. 相似文献
7.
In this paper, we establish the existence of multiple solutions for nonhomogeneous singular elliptic equations with cylindrical weights, by using Ekeland??s variational principle and mountain pass theorem without Palais?CSmale condition. 相似文献
8.
Mohamed Ben Ayed Rabeh Ghoudi Kamal Ould Bouh 《NoDEA : Nonlinear Differential Equations and Applications》2012,19(6):629-662
In this paper, we consider the problem of prescribing the scalar curvature under minimal boundary conditions on the four dimensional half sphere. Using dynamical and topological methods involving the study of the critical points at infinity of the associated variational structure, we prove some existence results like Bahri-Coron theorem. Furthermore, we consider the approximate subcritical problem and we construct some solutions which blow up at two different points, one of them lay on the boundary and the other one is an interior point. 相似文献
9.
Mohamed Ould M’hamed 《合成通讯》2013,43(22):2511-2528
This review aims to present the application of ball milling for the synthesis ofdifferent heterocyclic compounds in very good yields. The method is a simple, economical, and ecofriendly process for synthesizing heterocycles, which is a large family of organic compounds. They are extremely important and have wide-ranging pharmaceutical and industrial applications. 相似文献
10.