Over the last six years, highly active catalysts for the synthesis of cyclic carbonates from epoxides and carbon dioxide have been developed. Initial studies showed that bimetallic aluminium(salen) complexes [Al(salen)]2O formed active catalysts and kinetic studies allowed the catalytic cycle to be determined. The catalysts could be immobilized on silica, allowing them to be used in a gas phase...

Au/CeLaOx mixed oxide catalysts containing 0.5 to 1.0 wt% Au were prepared via coprecipitation with HAuCl4, the appropriate nitrate precursors, and either urea or Na2CO3 as the precipitant. BET surface area measurements for the Au/CeLaOx catalysts varied in the range of 16-107 m/g depending on the precipitant, aging time, and calcination conditions. The catalysts were tested for the selective o...

The catalytic oxidation of sulfur dioxide to sulfur trioxide over several binary (MxOy/TiO2) and ternary (V2O5/MXOY/TiO2) supported metal oxide catalysts was systematically investigated. The supported metal oxide components were essentially 100% dispersed as surface metal oxide species, as confirmed by Raman spectroscopy characterization. The sulfur dioxide oxidation turnover frequencies of the...

We study the linkage classes of homogeneous ideals in polynomial rings. An ideal is said to be homogeneously licci if it can be linked to a complete intersection using only homogeneous regular sequences at each step. We ask a natural question: if I is homogeneously licci, then can it be linked to a complete intersection by linking using regular sequences of forms of smallest possible degree at ...

Clustering of the texture images is a demanding part of multimedia database mining. Most of the natural textures are non-homogenous in terms of color and textural properties. In many cases, there is a need for a system that is able to divide the non-homogenous texture images into visually similar clusters. In this paper, we introduce a new method for this purpose. In our clustering technique, t...

Anomaly detection in large populations is a challenging but highly relevant problem. The problem is essentially a multihypothesis problem, with a hypothesis for every division of the systems into normal and anomal systems. The number of hypothesis grows rapidly with the number of systems and approximate solutions become a necessity for any problems of practical interests. In the current paper w...

We prove that a homogeneous Banach space B on the unit circle T can be embedded as a closed subspace of a dual space ΞB contained in the space of bounded Borel measures on T in such a way that the map B → ΞB defines a bijective correspondence between the class of homogeneous Banach spaces on T and the class of prehomogeneous Banach spaces on T. We apply our results to show that the algebra of a...

Networks have been extensively used to model various complex systems such as online social networks, co-authorship and citation networks and gene networks. Due to different kinds of variations such as temporal, spatial, topic and phenotypic variations, several variants of the same network may exist. For several practical problems, identifying the nodes that are changing between the networks pro...

We develop our general machinery of the Campbell-Hausdorff invariants of links, in the case of pure links, with emphasis on the connections with the lower central series of the pure braid groups. We present a complete simple set of rules for the Artin calculus of longitudes modulo the central series. We prove that if two pure links differ by an order k pure braid commutator, then their order k ...

Abstract—In this paper an unsupervised color image segmentation method is suggested. Color image segmentation is an important but still open problem in image processing. At first, FCM is applied to the image and the cluster centers are obtained. Quite similar to the famous TSK fuzzy control model, we form several rules (IF-THEN like) for pixel classification. The results obtained from the rules...