MoS2 micro-pyramids have demonstrated interesting properties in the fields of photonics and non-linear optics. In this work, we show the excitonic absorption and cathodoluminescence (CL) emission of MoS2 micro-pyramids grown by chemical vapor deposition (C ...
A thrackle is a graph drawn in the plane so that every pair of its edges meet exactly once: either at a common end vertex or in a proper crossing. We prove that any thrackle of n vertices has at most 1.3984n edges. Quasi-thrackles are defined similarly, ex ...
The optimal power flow (OPF) problem, a fundamental problem in power systems, is generally nonconvex and computationally challenging for networks with an increasing number of smart devices and real-time control requirements. In this paper, we first investi ...
Although the grain refinement of yellow gold alloys with Jr has been used in industry and known for nearly half a century, the basic mechanism is still unknown. The present contribution shows that the mechanism is the same as that evidenced recently in Al- ...
Described are the synthesis and characterization of two, potentially tetradentate, N2S2 Schiff-base ligands, containing a disulfide bond, N,N'-bis(3-phenylprop-2-en-l-ylidene)-2,2'-disulfanediyldianiline (L-1) and N,N'-bis(3,3-diphenylprop-2-en-1-ylidene)- ...
A topological graph G is a graph drawn in the plane with vertices represented by points and edges represented by continuous arcs connecting the vertices. If every edge is drawn as a straight-line segment, then G is called a geometric graph. A k-grid in a t ...
The equiaxed solidification of Al-20 wt.% Zn alloys revealed an unexpectedly large number of fine grains which are in a twin, or near-twin, relationship with their nearest neighbors when minute amounts of Cr (1000 ppm) are added to the melt. Several occurr ...
We study some variants of Conway’s thrackle conjecture. A tangle is a graph drawn in the plane such that its edges are represented by continuous arcs, and any two edges share precisely one point, which is either a common endpoint or an interior point at wh ...
It is shown that 2-dimensional subdivisions can be made regular by moving their vertices within parallel 1-dimensional spaces. As a consequence, any 2-dimensional subdivision is projected from the boundary complex of a 4-polytope. ...
A drawing of a graph in the plane is called a thrackle if every pair of edges meet precisely once, either at a common vertex or at a proper crossing. According to Conway's conjecture, every thrackle has at most as many edges as vertices. We prove this conj ...