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排序方式: 共有146条查询结果,搜索用时 546 毫秒
51.
52.
Abdon Eddy Choque Rivero Andreas Lasarow Armin Rahn 《Complex Analysis and Operator Theory》2011,5(2):513-543
By Cayley transformation, there is an interplay between matrix-valued Carathéodory and Schur functions in the unit disk. One
of the main aims of the paper is to study this interplay with a view to the fact that the matrix function given by the values
of a Carathéodory function via Moore–Penrose inverses is also a Carathéodory function. In doing so, we also analyze ranges
and null spaces of the values of the matrix function in question and get some results of independence concerning the concretely
chosen point of the domain. 相似文献
53.
Synthesis of 1-oxa-3,8-diazospiro [4,5] decan-2-ones from 4-pyridone by addition of trimethylsilyl cyanide. 相似文献
54.
G. I. Stegeman R. Stegeman C. Rivero K. Richardson T. Cardinal M. Couzi 《Laser Physics》2006,16(6):902-910
The Raman effect, by which light is frequency shifted by a vibrational mode, enters into a number of phenomena in nonlinear optics. Here, we summarize our progress in identifying glass materials with potentially useful Raman properties, methods for measuring the strength of the Raman effect and its spectral dependence, and the properties of a number of different families of glasses. Glasses with both larger peak Raman susceptibilities and larger bandwidths relative to fused silica are reported. 相似文献
55.
56.
Salvador González A Gómez Arrayás R Rodríguez Rivero M Carretero JC 《Organic letters》2008,10(19):4335-4337
Both cyclic and acyclic silyl dienol ethers participate efficiently in the asymmetric vinylogous Mannich reaction of N-2-thienylsulfonylimines catalyzed by copper(I) complexes of Fesulphos ligands. This procedure displays wide imine and nucleophile versatility, high enantiocontrol, and complete gamma-regioselectivity in most cases examined. The mild sulfonamide deprotection allows the resulting products to be readily transformed into optically active delta-lactams or 5-hydroxy-2-piperidone derivatives. 相似文献
57.
A facile synthesis of 5-dialkylamino-6-aryl-(2H)-pyridazin-3-one from 5,6-dichloropyridazinone was carried out by using a palladium-catalyzed Suzuki-Miyaura cross coupling of 6-chloro-5-dialkylaminopyridazinone 1 with various arylboronic acids (3 equiv) as the key transformation. The Suzuki-Miyaura cross-coupling reaction proceeded smoothly under microwave irradiation at 135-140 degrees C for 30 min with 5 mol % of Pd catalyst in moderate to good isolated yields. The use of a CombiPhos Pd6 mixture catalyst system and a single Pd-SPhos catalyst system was evaluated. 相似文献
58.
Oscar L Domínguez Rivero Angel A Juan Pérez Ignacio A de la Nuez Pestana Djamila Ouelhadj 《The Journal of the Operational Research Society》2016,67(1):37-53
This paper discusses the Two-dimensional Loading Vehicle Routing Problem with Heterogeneous Fleet, Sequential Loading, and Item Rotation (2L-HFVRP-SR). Despite the fact that the 2L-HFVRP-SR can be found in many real-life situations related to the transportation of voluminous items, where heterogeneity of fleets, two-dimensional packing restrictions, sequential loading, and items rotation have to be considered, this rich version of vehicle routing-and-packing problem has been rarely analysed in the literature. Accordingly, this paper contributes to filling the gap by presenting a relatively simple-to-implement algorithm which is able to provide state-of-the-art solutions for such a complex problem in relatively short computational times. The proposed algorithm integrates inside an Iterated Local Search framework, biased-randomized versions of both vehicle routing and packing heuristics. The efficiency of the proposed algorithm is validated throughout an extensive set of computational tests. 相似文献
59.
60.
泥沙输运模拟综述——现状及其发展趋势 总被引:1,自引:0,他引:1
随着流体力学中数值方法的飞速发展,计算模型已经成为研究流体运动,泥沙输运和不同环境(诸如河流,湖泊及沿海地区)中相应污染物归趋过程等方面非常有吸引力的工具,在过去的30多年里,发展了许多计算水动力学/泥沙输运模型.文章追溯当前具有代表性的(一维、二维、三维)模型的发展历程,描述他们各自的特点,优势及局限,力图作为对模型方面感兴趣读者的第一指南,同时也为大家讨论模型的局限性,未来的发展趋势和研究需求方面搭建一个平台.给出了模型的表达,时空特性,水动力学和沉积物的耦合方式,处理非恒定流,推移质和悬移质,泥沙交换过程,泥沙类型(粘性或非粘性)及非均匀泥沙输运的能力.总结了不同模型的应用实例,读者可以运用这些例子作为研究模型设置,模型率定及模型验证的参考.给出了选择泥沙输运模型应遵循的原则,模型输入及率定方面存在的问题及改进的途径.探讨了现有水动力学/泥沙输运模型在处理复杂湍流,泥沙携带,流动与输沙耦合,非均匀泥沙,离散和扩散系数,河岸来沙处理等方面的局限性及改进的方向.最后,对基于多相流思想的泥沙输运模型及其它一些交叉性问题作了评述与展望. 相似文献