The use of X-ray radioscopy for in-situ studies of metal foam formation and evolution is reviewed. Selected results demonstrate the power of X-ray radioscopy as diagnostic tool for metal foaming. Qualitative analyses of foam nucleation and evolution, drainage development, issues of thermal contact, mold filling, cell wall rupture and more are given. Additionally, quantitative analyses based on ...

Foam-based materials are promising micro-structured materials with interesting thermal and acoustical properties. The control of the material morphology requires counteracting all the destabilizing mechanisms during their production, starting with the drainage process, which remains to be understood in the case of the complex fluids that are commonly used to be foamed. Here we perform measureme...

The present work was aimed to examine the effects of incorporation of each of two different types of nanoclay, i.e. Cloisite Na+ and Cloisite 30B, into PVA foam on cellular morphology and water absorption capacity. Foam samples containing 0.0-10.0 wt% of each of the two types of nanoclay alone were prepared using mechanical foaming. Accordingly, PVA/organoclay/water suspensions were prepare...

The evolution of a foam is determined by drainage flow of the continuous (liquid) phase and coarsening (aging) of the dispersed phase (gas bubbles). Free-drainage experiments with slow- and fast-coarsening gases show markedly different dynamics and elucidate the importance of the coupling of the two effects. Strong coarsening leads to drainage times that are shorter (accelerated drainage) and i...

We compare extensive experimental results for the gravity-driven steady drainage of oil-in-water emulsions with two theoretical predictions, both based on the assumption of Poiseuille flow. The first is from standard foam drainage theory, applicable at low aqueous volume fractions, for which a correction is derived to account for the effects of the confinement of the emulsion. The second arises...

Protein flotation is a process in which protein molecules are enriched by adsorption at rising bubbles. The bubbles then form foam above the solution, where liquid drains down and dried foam, concentrated protein, extracted. Here, recovery rate purity of extract depend on stability, surface coverage, bubble size, gas flow rate, etc. In this work, we performed experiments using bovine serum albu...

Xanthan gum is used to stabilize aqueous foams in a wide number of commercial and industrial processes one the numerous hydrosoluble polymers slow foam drainage. The slowing effects viscosity on drainage flow have been well studied but situations leading delay are poorly described literature. aim this study was shed light mechanisms governing initiation. Drainage seems be result liquid retentio...

ABSTRACT: This paper presents the results of studies concerned with the preparation of fresh food foams based on egg white and various hydrocolloids including Iranian gum tragacanth, guar and xanthan gums at different concentrations (0.002-0.040% w/w). The basic physical parameters of the obtained foams such as overrun, stability and morphology of gas bubbles were measured. Viscosity measuremen...