We are interested in a version of graph colouring where there is a ‘co-site’ constraint value k. Given a graph G with a non-negative integral demand xv at each node v, we must assign xv positive integers (colours) to each node v such that the same integer is never assigned to adjacent nodes, and two distinct integers assigned to a single node differ by at least k. The aim is to minimise the spa...

Carbon Nanotube Field Effect Transistors (CNFETs), consisting of semiconducting single-walled Carbon Nanotubes (CNTs), show great promise as extensions to silicon CMOS and in large-area electronics. While there has been significant progress at a single-device level, a major gap exists between such results and their transformation into VLSI CNFET technologies. Major CNFET technology challenges i...

Monitoring the quality of frying oil is important for the health of consumers. This paper reports a microfluidic technique for rapidly quantifying the degradation of frying oil. The microfluidic device generates monodispersed water-in-oil droplets and exploits viscosity and interfacial tension changes of frying oil samples over their frying/degradation process. The measured parameters were corr...

Interfacial nanobubbles (INBs) on a solid surface in contact with water have drawn widespread research interest. Although several theoretical models have been proposed to explain their apparent long lifetimes, the underlying mechanism still remains in dispute. In this work, the morphological evolution of INBs was examined in air-equilibrated and partially degassed water with the use of atomic f...

Oil droplets loaded with surfactant propel themselves with a velocity up to 6 mm s(-1) when they are placed in an aqueous phase of NaOH solution or buffer solution. The required driving force for such motion is generated on the interface of the droplets by the change in interfacial tension, due to deprotonation of the surfactant. This force induces Marangoni convection, which gives rise to a ci...

The chemical surfactant flooding can mobilize the trapped oil by lowering the interfacial tension between oil and brine and in some cases altering the reservoir rock wettability. In this work, the effect of surfactants on oil/brine interfacial tension was experimentally investigated. First, the effect of surfactants concentration was surveyed. Afterwards, the effect of salinity on surfactant be...

We developed a novel method for fabrication of glass micromodels with varying depth (2.5-D) with no additional complexity over the 2-D micromodels' fabrication. Compared to a 2-D micromodel, the 2.5-D micromodel can better represent the 3-D features of multi-phase flow in real porous media, as demonstrated in this paper with three different examples. Physically realistic capillary snap-off and ...