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排序方式: 共有374条查询结果,搜索用时 15 毫秒
171.
Donal O’Regan 《Applied mathematics and computation》2009,215(5):1975-1983
An index theory is presented for compact (and more generally compact absorbing contractive) Ads (and more generally Ad) maps. 相似文献
172.
Donal ORegan Nikolaos S. Papageorgiou 《Nonlinear Analysis: Theory, Methods & Applications》2009,70(12):4386-4392
In this paper we consider a nonlinear Neumann problem driven by the p-Laplacian and with a Carathéodory right hand side nonlinearity f(z,x). The hypothesis on f(z,x) does not imply the coercivity of the corresponding Euler functional. Using variational arguments and critical groups we show that the problem has at least two nontrivial smooth solutions. 相似文献
173.
This article presents common fixed point theory for multivalued maps defined on complete gauge spaces. Our analysis is elementary and relies only on properties of the generalized Hausdorff pseudometric. 相似文献
174.
This paper discusses both the nonexistence of positive solutions for second-order three-point boundary value problems when the nonlinear term f(t, x, y) is superlinear in y at y = 0 and the existence of multiple positive solutions for second-order three-point boundary value problems when the nonlinear term f(t, x,y) is superlinear in x at +∞. 相似文献
175.
Motivated by a paper Chidume and Zegeye [Strong convergence theorems for common fixed points of uniformly L-Lipschitzian pseudocontractive semi-groups, Applicable Analysis, 86 (2007), 353–366], we prove several strong convergence theorems for a family (not necessarily a semigroup) ℱ = {T(t): t ∈ G} of nonexpansive or pseudocontractive non-self mappings in a reflexive strictly convex Banach space with a uniformly Gateaux differentiable norm, where G is an unbounded subset of ℝ+. Our results extend and improve the corresponding ones byMatsushita and Takahashi [Strong convergence theorems for nonexpansive
nonself-mappings without boundary conditions,Nonlinear Analysis, 68 (2008), 412–419],Morales and Jung [Convergence of paths for pseudo-contractive mappings in Banach spaces, Proceedings of American Mathematical Society, 128 (2000), 3411–3419], Song [Iterative approximation to common fixed points of a countable family of nonexpansive mappings,
Applicable Analysis, 86 (2007), 1329–1337], Song and Xu [Strong convergence theorems for nonexpansive semigroup in Banach spaces, Journal of Mathematical Analysis and Applications, 338 (2008), 152–161], Wong, Sahu, and Yao [Solving variational inequalities involving nonexpansive type mappings, Nonlinear Analysis, (2007) doi:10.1016/j.na. 2007.11.025] in the context of a non-semigroup family of non-self mappings.
相似文献
176.
Wakahara T D'Angelo P Miyazawa K Nemoto Y Ito O Tanigaki N Bradley DD Anthopoulos TD 《Journal of the American Chemical Society》2012,134(17):7204-7206
A novel supramolecular nanoarchitecture, comprising C(60)/Co porphyrin nanosheets, was prepared by a simple liquid-liquid interfacial precipitation method and fully characterized by means of optical microscopy, AFM, STEM, TEM, and XRD. It is established that the highly crystalline C(60)/Co porphyrin nanosheets have a simple (1:1) stoichiometry, and when incorporated in bottom-gate, bottom-contact field-effect transistors (FETs), they show ambipolar charge transport characteristics. 相似文献
177.
Luis Miguel Menndez Mndez Anthony Deally Donal F. O'Shea Matthias Tacke 《Heteroatom Chemistry》2011,22(2):148-157
From the reaction of 1‐methyl‐1 H‐pyr‐rolo[2,3‐b]pyridine ( 1a ),1‐(methoxymethyl)‐1 H‐pyrrolo[2,3‐b]pyridine ( 1b ), 1‐isopropyl‐1 H‐pyrrolo[2,3‐b]pyridine (1c ), and 1‐(4‐methoxybenzyl)‐1 H‐pyrrolo[2,3‐b]pyridine ( 1d ) under Vilsmeier–Haak conditions, the corresponding aldehydes in position 3 ( 2a–2d ) were synthesized. These aldehydes were transformed in the corresponding fulvenes ( 3a–3d ) by the Knoevenagel condensation and treated with Li[BEt3H] to obtain the corresponding lithiated cyclopentadienide intermediates ( 3′a–3′d ). These intermediates were, finally transmetallated to titanium with TiCl4 to yield the 7‐azaindol‐3‐yl‐substituted titanocenes bis {[(1‐methyl‐1‐H‐pyrrolo[2,3‐b]pyridin‐3‐yl)methyl] cyclopentadienyl} titanium(IV) dichloride ( 4a ), bis{[(1‐methoxymethyl‐1‐H‐pyrrolo[2,3‐b]pyridin‐3‐yl)methyl]cyclopentadienyl} titanium(IV)dichloride ( 4b ), bis{[(1‐Isopropyl‐1‐H‐pyrrolo[2,3‐b]pyridin‐3‐yl)methyl]cyclopentadienyl} titanium(IV) dichloride ( 4c ), and bis{[(4‐methoxybenzyl‐1‐H‐pyrrolo[2,3‐b]pyridin‐3‐yl)methyl]cyclopentadienyl} titanium(IV) dichloride ( 4d ). All the titanocenes had their cytotoxicity investigated through MTT‐based preliminary in vitro testing on the Caki‐1 cell lines to determinate their IC50 values. Titanocenes 4a–4c were found to have IC50 values of 120 ± 10, 83 ± 13, and 54 ± 12, µM respectively, whereas 4d showed no cytotoxic activity. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 22:148–157, 2011; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20668 相似文献
178.
Using fixed point methods, we prove the generalized Hyers–Ulam stability of homomorphisms in multi-C ? ternary algebras and of derivations on multi-C ? ternary algebras for the additive functional equation $$\sum_{i=1}^{m}f \bigg(mx_i+\sum_{j=1,\ j\ne i}^{m}x_j\bigg)+ f\bigg(\sum_{i=1}^{m}x_i\bigg)= 2f\bigg(\sum_{i=1}^{m}mx_i\bigg) \quad (m\in {\mathbb{N}},\ m\geqq2).$$ 相似文献
179.
In this paper we investigate the existence of solutions to impulsive problems with a p(t)-Laplacian and Dirichlet boundary value conditions. We introduce two types of solutions, namely a weak and a classical one which coincide because of the fundamental lemma of the calculus of variations. Firstly we investigate the existence of solution to the linear problem, i.e. a problem with a fixed rigth hand side. Then we use a direct variational method and next a mountain pass approach in order to get the existence of at least one weak solution to the nonlinear problem. 相似文献
180.
Carbolithiation of diphenylacetylene can be exploited to generate (E)-1-lithio-1,2-diphenylalkyl-1-enes which can be reacted in situ with triisopropylborate to stereoselectively provide (E)-1,2-diphenyl-1-alkylene boronic acids. These tetrasubstituted vinylboronic acids served as versatile intermediates for the generation of tetrasubstituted olefins with retention of stereochemistry. The application of this method for the stereoselective synthesis of (Z)-tamoxifen and related analogues is described. 相似文献