The study describes a homogenisation technique of developing Polyether ether ketone (PEEK) and calcium hydroxyapatite (cHAp) composite with periodic pattern lattice structures. continuum depiction the discrete structures was evaluated to retain PEEK cellulose properties cell applied dental implants. Design approaches were considered, using different software modelling optimise orthotropic mater...

The reaction of equimolar amounts of (n-Bu4N)[ReOCl4] and 2-(1-ethanolthiomethyl)-1methylimidazole (Htmi) in acetonitrile yielded cis-[ReOCl2(tmi)]. An X-ray diffraction study shows that tmi ̄ coordinates as a uninegative N,S,O-tridentate ligand to give distorted octahedral geometry around the rhenium(V) ion. The three donor atoms occupy a triangular face in an octahedron, with the alcoholate ox...

An earlier paper describes a program to prove the Kepler conjecture on sphere packings. This paper carries out the second step of that program. A sphere packing leads to a decomposition of R into polyhedra. The polyhedra are divided into two classes. The first class of polyhedra, called quasi-regular tetrahedra, have density at most that of a regular tetrahedron. The polyhedra in the remaining ...

The ratio of volume to crossing number of a hyperbolic knot is known to be bounded above by the volume of a regular ideal octahedron, and a similar bound is conjectured for the knot determinant per crossing. We investigate a natural question motivated by these bounds: For which knots are these ratios nearly maximal? We show that many families of alternating knots and links simultaneously maximi...

In this paper we address the potential gain of using compact MIMO antenna array configurations in conjunction with High Altitude Platforms (HAPs) diversity techniques in order to increase the capacity in HAP communication systems. For this purpose, we also propose a novel compact MIMO antenna which we denote as the “MIMOOctahedron” and compare its performance with the vector element antenna. Si...

X-band EPR spectra have been recorded at room temperature for V 0 2 + impurity in single crystals of t r is-Guanadiniumhexafluoroaluminate, [C(NH2)3]3A1F6 . 1 9 F super hyperfine structure has been observed on the 5 V hyperfine lines. V 0 2 + replaces Al 3 + to form an effective VOF5 complex. There are three possible V O bond orientations in the A1F6 octahedron but with differing occupancy fact...

Nanocrystals with high-index facets usually exhibit higher catalytic activities than those with only low-index facets. Trapezohedron-shaped (TS) In2O3 particles with exposed high-index {211} facets were successfully synthesized in an oleic acid (OA) and trioctylamine (TOA) system. It has been demonstrated that the gas sensing activity of TS In2O3 particles with exposed high-index {211} facets i...

The characteristics of electronic states of Cd-vacancies in CdTe, an important semiconductor for various technological applications, are under debate both from theoretical and experimental points of view. Experimentally, the Cd-vacancy in its negative charge state is found to have C3v symmetry and a (-1/-2) transition level at 0.4 eV. Our first principles density functional calculations with hy...