Packing in honeycomb networks

Molecules arranging themselves into predictable patterns on silicon chips could lead to microprocessors with much smaller circuit elements. Mathematically, assembling in predictable patterns is equivalent to packing in graphs. An H-packing of a graph G is a set of vertex disjoint subgraphs of G, each of which is isomorphic to a fixed graph H. If H is the complete graph K ₂, the maximum H-packing problem becomes the familiar maximum matching problem. In this paper we give algorithms to find a perfect packing of HC(n) with P ₆ and K _1,3 when n is even and thus determines their packing numbers. Further we also study the packing of HC(n) with 1, 3-dimethyl cyclohexane.     

Intramolecular Cyclization of 9,11‐Seco‐Estrane under Friedel–Crafts Reaction Conditions

An intramolecular cyclization of 17β‐acetoxy‐3‐methoxy‐9,11‐seco‐1,3,5(10)‐estratriene‐11‐oic acid under different Friedel–Crafts reaction conditions is described.     

Designing Self‐Supported Metal‐Organic Framework Derived Catalysts for Electrochemical Water Splitting

To achieve efficient water splitting, it is essential to develop catalysts with high electrochemical performance, enhanced durability and tunable properties. Most of the transition metal‐based catalysts employed for the water splitting have been fabricated on the solid‐electrode support by using binder, which decreases the activity and durability of the catalyst system. In this respect, self‐supported metal organic framework (MOF) derived catalysts have been introduced with enhanced catalytic activity and mechanical stability for the electrochemical water splitting. The self‐supported MOF derived catalysts exhibit improved electronic conductivity, high electrochemical surface area, enhanced mechanical stability and strong catalyst‐support interaction. Moreover, these catalysts possess highly porous and hollow structure with designed morphology and multi‐metallic composition. Recently, a tremendous effort has been provided to explore this newly growing field and new dimensions and directions have been achieved. Looking at this point, we have described here the basic principles of catalyst design from self‐supported MOF, structural and interface engineering by controlling the electronic structure of the catalysts to improve the water splitting activity. In addition, the challenges and difficulties associated with this field have been pointed out and addressed for the future progress in this field.     

Embedding hypercubes into cylinders, snakes and caterpillars for minimizing wirelength

We consider the problem of embedding hypercubes into cylinders to minimize the wirelength. Further, we show that the edge isoperimetric problem solves the wirelength problem of regular graphs and, in particular, hypercubes into triangular snakes and caterpillars.     

Enhancement of dielectric constant in PVDF polymer using dendrite-shaped PbS nanostructures

Dendrite-shaped PbS has been successfully synthesized using hydrothermal method on a large scale. The formation of dendrite-shaped PbS was confirmed by scanning electron microscopy (SEM). A detailed study of variations in dielectric properties on frequency and temperature shows that composites of PVDF and dendrite-shaped PbS have significantly higher dielectric constant than PVDF/PbS nanoparticles (NP) nanocomposites due to low percolation threshold.     

Concentration of fish serum albumin (FSA) in the aqueous extract of Indonesian Perciformes fishes’ muscle tissue

Fish serum albumin (FSA) is an aquatic resource that has potential to be developed as nutraceutical. Therefore, research was undertaken to assess albumin levels in the aqueous extract of muscle tissue of several Perciformes commonly available at a local fish market in Indonesia. Three random replicates for each of 17 Perciformes species were collected and assessed for their FSA content by application of a reversed-phase (C4) HPLC analytical method. Results of these analyses showed that the albumin concentration of the extracts was in the range 3.49–12.61 g/L, and that they varied significantly (P < 0.05) between species and families. This finding may mean that FSA levels are species and family dependent, something that could be investigated in future studies. As fishes from the family Scrombidae showed the highest concentration (12.61 g/L) of FSA, they would likely have the most value as a source for production of albumin-based nutritional and/or clinical products.