An efficient and eco-friendly method for the one-pot synthesis of 14-aryl-14H-dibenzo [a,i]xanthene-8,13-dione derivatives has been developed in the presence of Fe3O4@SiO2 core-shell nanoparticles. The multi-component reactions of 2-hydroxy-1,4-naphthoquinone, β-naphthol and aldehydes were efficiently catalyzed using novel nano-scale materials under reflux conditions. The present method offers ...

Metastructures and metaterms have been proposed to extend Prolog systems 6, 5]. They enable special purpose uniications to be speciied. They are useful to implement for example coroutining and new domains of computation. In both cases, information is attached to variables, which then are encoded with metaterms or metastructures. This information must be taken into account during uniication. Pro...

Consider two graphs G1 and G2 on the same vertex set V and suppose that Gi has mi edges. Then there is a bipartition of V into two classes A and B so that for both i = 1, 2 we have eGi(A,B) ≥ mi/2 − √ mi. This answers a question of Bollobás and Scott. We also prove results about partitions into more than two vertex classes.

this paper is concerned with the consensus tracking problem of high order mimo nonlinear multi-agent systems. the agents must follow a leader node in presence of unknown dynamics and uncertain external disturbances. the communication network topology of agents is assumed to be a fixed undirected graph. a distributed adaptive control method is proposed to solve the consensus problem utilizing re...

This paper studies the parameter estimation of a general multi-input, multi-output multi-rate system in the frequency-domain. Two methods, named dividing to subsystems and input extension, are introduced for dealing with multi-rate systems and the later method is easily used to convert a multi-input, multi-output multi-rate system to several sub-problems with fast input updating and slow output...

In the present paper several q−integral inequalities are presented, some of them are new and others are generalizations of known results.

Humans have used arguments for defending or refuting statements long before the creation of logic as a specialized discipline. This can be interpreted as the fact that an intuitive notion of “logical consequence” or a psychic disposition to articulate reasoning according to this pattern is present in common sense, and logic simply aims at describing and codifying the features of this spontaneou...

Writing a program to solve a problem is a process that can be divided into two phases: first, we invent a mental model of the solution; secondly, we map the mental model onto a physical representation. The mental model is multidimensional and syntax-free; in today’s textual programming languages, the physical representation is singledimensional and syntax-burdened. In fact, it hasn’t changed gr...

We consider solutions to the Euler equations in the whole space from a certain class, which can be characterized, in particular, by finiteness of mass, total energy and momentum. We prove that for a large class of right-hand sides, including the viscous term, such solutions, no matter how smooth initially, develop a singularity within a finite time. We find a sufficient condition for the singul...

0 binary, I-binary: The binary GCD algorithm ([lS]) and its improvement for multidigit integers (Gosper, see [12]). We compare the executron times of several algoixtliiiis for computing the G‘C‘U of arbitrary precasion iirlegers. These algorithms are the known ones (Euclidean, brnary, plus-mrnus), and the improved variants of these for multidigit compzltation (Lehmer and similar), as well as ne...