Convex hexagonal systems (CHS) i. e., hexagonal systems with no bay regions are studied. Among CHS with a fixed number of hexagons, the species with minimal/maximal number of inlets have minimal/maximal or maximal/minimal values for a variety of vertex–degree-based topological indices. These extremal CHS are characterized. 1 Convex hexagonal systems In this paper we study a special class of hex...

Silicon crystallizes in the diamond-cubic phase and shows only a weak emission at 1.1 eV. Diamond-hexagonal silicon however has an indirect bandgap at 1.5 eV and has therefore potential for application in opto-electronic devices. Here we discuss a method based on advanced silicon device processing to form diamond-hexagonal silicon nano-ribbons. With an appropriate temperature anneal applied to ...

Two-dimensional stacks of dissimilar hexagonal monolayers exhibit unusual electronic, photonic and photovoltaic responses that arise from substantial interlayer excitations. Interband excitation phenomena in individual hexagonal monolayer occur in states at band edges (valleys) in the hexagonal momentum space; therefore, low-energy interlayer excitation in the hexagonal monolayer stacks can be ...

Hexagonal hierarchical microtubular structures are produced by diphenylalanine self-assembly and the ratio of the relative humidity in the growth chamber to the diphenylalanine concentration (defined as the RH-FF ratio) determines the microtubular morphology. The hexagonal arrangement of the diphenylalanine molecules first induces the hexagonal nanotubes with opposite charges on the two ends, a...

In this paper, an artificial neural network model is proposed to find out the resonant frequency of a metamaterial based Hexagonal Split Ring Resonator (SRR). The main advantage of Hexagonal SRR is small electrical size at resonance (electrically small) in the microwave regime. The method can be used for a wide range of different depending parameters (effective radius of the Hexagonal ring, spl...

In this paper we investigate the advantages of using hexagonal grids in raster and volume graphics. In 2D, we present a hexagonal graphical model based on a hexagonal grid. In 3D, we introduce two honeycomb graphical models in which the voxels are hexagonal prisms, and we show that these are the only possible models under certain reasonable conditions. In the framework of the proposed models, w...

The inner surfaces of a hexagonal mesoporous silica (HMS) are treated by chlorotrimethylsilane, either directly or through vapor or liquid endcapping. The directly treated inner surfaces have the highest effective interfacial tension, and the liquid endcapping treated surfaces have the largest accessible nanopore volume. The difference in the treatment results may be attributed to the distinct ...

Hexagonal quasigroup is idempotent, medial and semisymmetric quasigroup. In this article we define and study vectors, sum of vectors and transfers. The main result is the theorem on isomorphism between the group of vectors, group of transfers and the Abelian group from the characterization theorem of the hexagonal quasigroups. 1. Hexagonal quasigroup Hexagonal quasigroups are defined in article...

The gel-to-fluid and lamellar-to-HII-hexagonal thermotropic phase transitions of egg-yolk phosphatidylethanolamine have been examined by Fourier-transform infrared spectroscopy under a variety of conditions, namely excess water at pH 5.0, excess water at pH 9.5 and low hydration. The various lamellar and hexagonal phases have been characterized by X-ray diffraction. At pH 5.0, gel-fluid and lam...