Abstract We study the magnon spectrum of stacked zig-zag chains point magnetic dipoles with an easy axis. The anisotropy due to dipolar interactions and two-point basis chain unit cell combine give rise topologically non-trivial bands in 2D lattices. Adjusting distance between two sublattice sites causes a band touching, which triggers exchange Chern numbers volume switching sign thermal conduc...

This study examines Thematic Development types based on the framework of Systemic Functional Linguistics that are used by tertiary students. It aims to find out how students produce effectively and efficiently their report texts. The data were all clauses taken from fifteen students’ text divided into three levels: high, middle, low achievement. findings showed there patterns in text, they Them...

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1,4-Substituted triazole oligomers made from quaternary amino acid derivatives present a conformational behaviour with similarities to that of natural peptides. Twisted strand and zig-zag type conformations have both been obtained in the crystal state. In a solution signs of weakly ordered structures have been detected depending on the substituents and the solvents used.

The Wiener index of a graph G is defined as the sum of all distances between distinct vertices of G. In this paper an algorithm for constructing distance matrix of a zig-zag polyhex nanotube is introduced. As a consequence, the Wiener index of this nanotube is computed.

The compositions, or ordered partitions, of integers, fall under certain natural classes. In this expository paper we highlight the most important classes by means of bijective proofs. Some of the proofs rely on the properties of zig-zag graphs the graphical representations of compositions introduced by Percy A. MacMahon in his classic book Combinatory Analysis.

The synthesis, structural characterization and magnetic properties of a 1D zig-zag coordination polymer based on a cation-cation [(U(V)O2)Mn(II)] repeated unit are reported; it shows single chain magnet (SCM) behaviour with a high energy barrier of 122 K.