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51.
The synthesis of a novel family of cyano‐bridged trimetallic coordination polymers (CPs) with various compositions and shapes has been reported by changing the compositional ratios of Fe, Co, and Ni species in the reaction system. In order to efficiently control the nucleation rate and the crystal growth, trisodium citrate dihydrate plays an important role as a chelating agent. After the obtained cyano‐bridged trimetallic CPs undergo thermal treatment in air at three different temperatures (250, 350, and 450 °C), nanoporous spinel metal oxides are successfully obtained. Interestingly, the obtained nanoporous metal oxides are composed of small crstalline grains, and the grains are oriented in the same direction, realizing pseudo‐single crystals with nanopores. The resultant nanoporous spinel oxides feature interesting magnetic properties. Cyano‐bridged multimetallic CPs with various sizes and shapes can provide a pathway toward functional nanoporous metal oxides that are not attainable from simple cyano‐bridged CPs containing single metal ions.  相似文献   
52.
Selective solvent extraction (SSX) of Cr(VI) and recovery was evaluated by using a homologous series of symmetric imidazolium bromide salts (SIMs) having various alkyl chain length. Therefore, propyl, pentyl, hexyl, octyl, and decyl substituted SIMs were used as an ion carrier. The executive parameters affecting both extraction and stripping conditions were investigated for optimization. Finally, a direct correlation was observed a between increasing alkyl chain length and selective Cr(VI) extraction from acidic solutions containing Cr(VI), Fe(III), Co(II), Cd(II), Ni(II). This relationship was reversed in the stripping conditions. Optimal extraction and stripping were obtained for SIM5 and SIM2 as 97.49% and 70.00%, respectively.  相似文献   
53.
In an earlier paper the first author [Ekrem Savas, Factors for |A|k|A|k summability of infinite series, Comput. Math. Appl. 53 (7) (2007) 1045–1049. [3]] obtained a summability factor theorem for absolute summability of the order k≥1k1. In this paper we extend that result to doubly infinite matrices.  相似文献   
54.
The notion of asymptotically equivalent sequences was presented by Pobyvanets in 1980. Using this definition, he presented Silverman–Toeplitz-type matrix conditions that ensure that a summability matrix preserves asymptotic equivalency. This work begins with an extension of Pobyvanets’ definition of convergence in probability. This definition is also used to present Silverman–Toeplitz-type conditions for ensuring that a summability matrix preserves asymptotic probability equivalence. In addition, we shall also present a Marouf-type characterization of such a sequence space.  相似文献   
55.
The fatty acid composition of the seed oil of 23 Stachys taxa was analysed by GC/MS. The main compounds were found to be linoleic (27.1-64.3%), oleic (20.25-48.1%), palmitic (4.3-9.1%), stearic (trace to 5.2%) and 6-octadecynoic (2.2-34.1%) acids. The latter compound could be used as a chemotaxonomic marker of the genus Stachys. A cluster analysis was performed for comparison and characterisation of the seed oil from Stachys species.  相似文献   
56.
A lower triangular infinite matrix is called a triangle if there are no zeros on the principal diagonal. The main result of this paper gives a minimal set of sufficient conditions for a double triangle T to be a bounded operator on   相似文献   
57.
The paper deals with absolute summability factors for infinite series. The main purpose of this paper is to generalize a recent paper of Savas (2009) [2].  相似文献   
58.
Ekrem Aydmer 《中国物理快报》2006,23(12):3352-3355
The spatial components of the autocorrelation function of noninteracting dipoles are analytically obtained in terms of rotational Brownian motion on the surface of a unit sphere using multi-level jumping formalism based on Debye's rotational relaxation model, and the rotational relaxation functions are evaluated.  相似文献   
59.
In this study, dependence on site dilution of critical and compensation temperatures of a two-dimensional mixed spin-1/2 and spin-1 system has been investigated with Monte Carlo simulation. The dependence of the thermal and magnetic behaviors on dilution of mixed spin system has been discussed. We have shown that the critical and compensation temperatures of diluted mixed spin system linearly decrease with increasing number of diluted sites.  相似文献   
60.
Let A denote the set of kth absolutely summable double series. In this paper it is shown that every double conservative Hausdorff matrix is a bounded operator on A.  相似文献   
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