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21.
I. Perez-Alvarez J. L. Martinez-Vidal M. Villafranca E. Gonzalez-Pradas F. Salinas 《Journal of Thermal Analysis and Calorimetry》1989,35(7):2341-2346
Solid crystalline complexes of furan-2-hydroxamic acid (FHA) and six metallic divalent cations (Ca(II), Ba(II), Co(II), Ni(II), Cu(II), and Cd(II)) were prepared. In all cases the stoichiometry was 2(FHA)1 (cation). The solids were characterized by elemental analysis, TG, DSC and IR techniques.
Zusammenfassung Es wurden feste, kristalline Komplexe von Furan-2-hydroxamsäure (FHA) und sechs verschiedenen bivalenten Metallkationen hergestellt: Ca(II), Ba(II), Co(II), Ni(II), Cu(II) und Cd(II). Die stöchiometrische Zusammensetzung betrug in allen Fällen 2(FHA)1(Kation). Die Feststoffe wurden mittels Elementaranalyse, TG-, DSC- und IR-Techniken charackterisiert.
-2- , , , , . : 21. , , .相似文献
22.
Universally prestarlike functions (of order α ≤ 1) in the slit domain
L:=\mathbbC\[1,¥]{\Lambda:=\mathbb{C}{\setminus}[1,\infty]} have recently been introduced in Ruscheweyh et al. (Israel J Math, to appear). This notation generalizes the corresponding
one for functions in the unit disk
\mathbbD{\mathbb{D}} (and other circular domains in
\mathbbC{\mathbb{C}}). In this paper we study the behaviour of universally prestarlike functions under the Hadamard product. In particular it
is shown that these function classes (with α fixed), are closed under convolution, and that their members, as Hadamard multipliers, also preserve the prestarlikeness
(of the same order) of functions in arbitrary circular domains containing the origin. 相似文献
23.
Gomez MartIn R. Morente J.A. Salinas A. 《Electromagnetic Compatibility, IEEE Transactions on》1987,(2):169-174
The radiation and reception characteristics of a planar array of straight-wire coupled antennas are analyzed by a numerical method in the time domain. The numerical method allows us to calculate some significant magnitudes in an array of coupled wire antennas, such as the frequency dependence of the self- and mutual impedances between antennas. The antennas are fed by a time-varying Gaussian pulse, and they are loaded with various nonlinear elements to exert some control over the radiation field. The results are used to show how the monopulse technique with the slope pattern promises a much higher accuracy of angle measurement for a target. 相似文献
24.
25.
On the mean-field Ising model in a random external field 总被引:1,自引:0,他引:1
We use a method developed by van Hemmen to obtain the free energy of the mean-field Ising model in a random external magnetic field. Some results of previous mean-field calculations are confirmed and generalized. The tricritical point in the global phase diagram is discussed in detail. We also consider different probability distributions of the random fields and provide some proofs regarding the conditions for the existence of a tricritical point. 相似文献
26.
Non‐intrusive reduced‐order modeling for multiphase porous media flows using Smolyak sparse grids 下载免费PDF全文
Dunhui Xiao Zhi Lin Fangxin Fang Christopher C. Pain Ionel M. Navon Pablo Salinas Ann Muggeridge 《国际流体数值方法杂志》2017,83(2):205-219
In this article, we describe a non‐intrusive reduction method for porous media multiphase flows using Smolyak sparse grids. This is the first attempt at applying such an non‐intrusive reduced‐order modelling (NIROM) based on Smolyak sparse grids to porous media multiphase flows. The advantage of this NIROM for porous media multiphase flows resides in that its non‐intrusiveness, which means it does not require modifications to the source code of full model. Another novelty is that it uses Smolyak sparse grids to construct a set of hypersurfaces representing the reduced‐porous media multiphase problem. This NIROM is implemented under the framework of an unstructured mesh control volume finite element multiphase model. Numerical examples show that the NIROM accuracy relative to the high‐fidelity model is maintained, whilst the computational cost is reduced by several orders of magnitude. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
27.
Barluenga J Fernández-Rodríguez MA Aguilar E Fernández-Marí F Salinas A Olano B 《Chemistry (Weinheim an der Bergstrasse, Germany)》2001,7(16):3533-3544
A new procedure for the synthesis of 1,3,4-trisubstituted and 1,4-disubstituted pyrrolidin-2-one derivatives in an enantioselective fashion is reported. The 1,3-dipolar cycloaddition of (+/-)-menthol and (-)-8-phenylmenthol derived Fischer alkoxy alkenyl carbene complexes with in situ generated functionalized azomethine ylides gives the corresponding cycloadducts as chelated tetracarbonyl Fischer carbene complexes. Only one regioisomer is detected in all cases, and the diastereoselectivity of the reaction is very high when (-)-8-phenylmenthol derived carbenes are employed. Oxidation and further transformation of the cycloadducts provide an easy access to pyrrolidin-2-ones. The anti-inflammatory and antidepressant drug (+)-Rolipram is readily prepared in four steps in a 20% overall yield by taking advantage of this newly developed methodology. 相似文献
28.
Hase M. O. de Almeida J. R.L. Salinas S. R. 《The European Physical Journal B - Condensed Matter and Complex Systems》2005,47(2):245-249
We use the replica method in order to obtain an expression for the
variational free energy of an Ising ferromagnet on a Viana-Bray lattice in
the presence of random external fields. Introducing a global order
parameter, in the replica-symmetric context, the problem is reduced to the
analysis of the solutions of a nonlinear integral equation. At zero
temperature, and under some restrictions on the form of the random fields,
we are able to perform a detailed analysis of stability of the
replica-symmetric solutions. In contrast to the behaviour of the
Sherrington-Kirkpatrick model for a spin glass in a uniform
field, the paramagnetic solution is fully stable in a sufficiently large
random field. 相似文献
29.
I. Durán-Merás A. Muñoz De La Peña F. Salinas lópez M. I. Rodríguez Cáceres 《Journal of inclusion phenomena and macrocyclic chemistry》2005,51(3-4):137-142
The fluorimetric characteristics of pipemidic acid (PIPE) have been investigated. It has been proven that the fluorescence emission band of pipemidic acid at 439 nm is significantly intensified in the presence of γ-cyclodextrin. The inclusional complexation between the antibacterial pipemidic acid and γ-cyclodextrin (γ-CD) has been studied. A 1:1 stoichiometry of the complex was established and its association constant was calculated by a nonlinear regression method, monitoring the changes in the fluorescence signal of pipemidic acid in the presence of γ-CD. According to the results obtained, a spectrofluorimetric method for the determination of PIPE has been proposed. The best limits of detection and quantification were obtained in presence of γ-CD, in acidic media. The dynamic range of the method was comprised between 0.18 and 1.40 μg/ml. 相似文献
30.
We give necessary and sufficient conditions on the wavelet coefficients of a function for being a member of some BMOφ (w) space. We achieve this characterization for a wide variety of wavelet systems. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献