We provide a simple proof of the existence of a planar separator by showing that it is an easy consequence of the circle packing theorem. We also reprove other results on separators, including: (A) There is a simple cycle separator if the planar graph is triangulated. Furthermore, if each face has at most d edges on its boundary, then there is a cycle separator of size O ` ? dn ̆ . (B) For a set...

We use AC impedance methods to investigate the effect of mechanical deformation on ion transport in commercial separator membranes and lithium-ion cells as a whole. A Bruggeman type power law relationship is found to provide an accurate correlation between porosity and tortuosity of deformed separators, which allows the impedance of a separator membrane to be predicted as a function of deformat...

Recently a large number of graph separator problems have been proven to be NPHard. Amazingly we have found that α-Subgraph-Balanced-Vertex-Separator, an important variant, has been overlooked. In this work “Yet Another Graph Partitioning Problem is NP-Hard” we present the surprising result that α-SubgraphBalanced-Vertex-Separator is NP-Hard. This is despite the fact that the constraints of our ...

electrochemical impedance spectroscopy (eis) is a suitable and powerful diagnostic testing method for fuel cells (fcs) since it is non-destructive and provides useful information about fc performance and its components. in this study, for the first time, a 500w cascade type 4 cells stack with integrated humidifier, water separator and internal manifolds was designed, fabricated and tested. the ...

In this study simple catalytic test experiment was performed in a flask of rotary evaporator for dechlorination of nitrochlorobenzene (NCB) over two samples of Ni/LaAl2 O3 nanocatalysts (C1 and C2). In the reaction, Ni acts as a catalyst to collect hydrogen gas in aqueous solution and dissociate it to produce active hydrogen atoms for replacing the chlorine. The catalysts were characterized by ...

In the Tabas coal preparation plant (SE Iran), -50 + 6 mm raw coal was treated in a 700 mm two-stage two-density Tri-Flo dynamic dense medium separator. In order to study the circuit performance and to evaluate the separator efficiency, 32 mm cubic density tracers were used in the range of 1.28-2.1 g/cm3 and under different operational conditions. The performance of Tri-Flo was evaluated in a r...