A conceptual pore level model (Chem. Eng. Sci. 57 (2002) 3401) of spreading of liquid over internally wet porous particles is applied to explain reported rector level enhancement in wetting of trickle bed reactor (Ind. Eng. Chem. Res. 36 (1997) 5133). It is con6rmed that a symbiotic relationship exists between internal and external wetting of porous particles whereby each enhances the other. Fu...

The process of nickel electroforming is becoming increasingly important in the manufacture of MST products, as it has the potential to replicate complex geometries with extremely high fidelity. Electroforming of nickel uses multi-component electrolyte formulations in order to maximise desirable product properties. In addition to nickel sulphamate (the major electrolyte component), formulation a...

Drops and bubbles are nonspreading, local, compactly supported features. They are also equilibrium configurations in partial wetting phenomena. Yet, current macroscopic theories of capillary-dominated flow are unable to describe these systems. We propose a framework to model multiphase flow in porous media with nonspreading equilibrium configurations. We illustrate our approach with a one-dimen...

The stabilization of nanoscale surficial amorphous films (SAFs) for Bi2O3 on ZnO, VOx on TiO2, SiOx on Si, and several other oxide systems provides evidence for the existence of prewetting phenomena with analogies in water and other simple systems, as well as the stabilization of intergranular amorphous films in ceramics. Experimental results show that in the subeutectic regime, the equilibrium...

When a small amount (less than 1%) of a second immiscible liquid is added to the continuous phase of a suspension, the rheological properties of the admixture are dramatically altered and it can change from a fluid-like to a gel-like state. The rheological properties can be modified through changes in the particle size, temperature induced changes to the interfacial tension, and through the add...

We report measurements of the state of wetting of two liquid mixtures at coexistence near their respective critical consolute temperatures. Borosilicate glass capillary tubes were reacted with hexamethyldisilazane to produce substrates of uniform and controlled silylation. Surfaces of low coverage exhibit a series of first-order partial to complete wetting transitions and obey a short-range for...

It is well documented in the modem literature that the conventional laws of capillarity such as Laplace, Kelvin, and Young-Dupre equations are not adequate when applied to fluids confined by particulate and porous materials. Specifics of interactions of fluids with solid surfaces at the nanoscale are of special engineering importance in view of recent discovery of carbon nanotubes and rapidly g...

We present a theoretical study related to a recent experiment on the coalescence of sessile drops. The study deals with the kinetics of relaxation towards equilibrium, under the action of surface tension, of a spheroidal drop on a flat surface. For such a nonspherical drop under partial wetting conditions, the dynamic contact angle varies along the contact line. We propose a new nonlocal approa...

We study the spreading of spheroidal aggregates of cells, expressing a tunable level of E-cadherin molecules, on glass substrates decorated with mixed fibronectin and polyethylene glycol. We observe the contact area by optical interferometry and the profile by side-view microscopy. We find a universal law of aggregate spreading at short times, which we interpret through an analogy with the spre...