sl 3-Foams and the Khovanov-Lauda categorification of quantum sl k. Abstract In this paper I define certain interesting 2-functors from the Khovanov-Lauda 2-category which categorifies quantum sl k , for any k > 1, to a 2-category of universal sl 3 foams with corners. For want of a better name I use the term foamation to indicate those 2-functors. I conjecture the existence of similar 2-functor...

Capillary forces arising during the evaporation of liquids from dense carbon nanotube arrays are used to reassemble the nanotubes into two-dimensional contiguous cellular foams. The stable nanotube foams can be elastically deformed, transferred to other substrates, or floated out to produce free-standing macroscopic fabrics. The lightweight cellular foams made of condensed nanotubes could have ...

We have developed a realistic simulation of 2D dry foams under quasistatic shear. After a short transient, a shear-banding instability is observed. These results are compared with measurements obtained on real 2D (confined) foams. The numerical model allows us to exhibit the mechanical response of the material to a single plastication event. From the analysis of this elastic propagator, we prop...

The combination of high strength and toughness, excellent wear resistance and moderate density makes zirconia-toughened alumina (ZTA) a favorable ceramic, and the foam version of it may also exhibit excellent properties. Here, ZTA foams were prepared by the polymer sponge replication method. We developed an immersion infiltration approach with simple equipment and operations to fill the hollow ...

This work focuses on the use of metal foams, a relatively new class of materials, for high added-value electromagnetic (EM) shields. First, the Shielding Effectiveness (SE) of aluminum foam slabs is experimentally evaluated, showing very good shielding properties. Successively, accurate numerical models of metal foams are proposed and used in a proprietary Variable-Mesh Parallel Finite Differen...

BACKGROUND Exposure to airborne wheat allergen is a well-known cause of bakers' allergy and asthma. Airborne wheat allergen can be measured by enzyme immunoassays (EIAs) in extracts of inhalable dust samples, but only limited knowledge is available on the size distribution of wheat allergen-carrying particles. Recently, a new sampling medium, porous polyurethane foam, has been introduced for th...

Reticulated nickel foams were alloyed with 8–9 wt% Al or 14–18 wt% Cr and 5–9 wt% Al in a three-step method consisting of (i) gas-phase deposition of Cr and/or Al onto the struts of a pure Ni foam by pack-cementation at 1000 C; (ii) homogenization at 1200 C to remove concentration gradients and to solutionize the alloyed struts; (iii) aging at 900 C to form c0 precipitates within the struts. Th...

Wet foams are used in many important technologies either as end or intermediate products. However, the thermodynamic instability of wet foams leads to undesired bubble coarsening over time. Foam stability can be drastically improved by using particles instead of surfactants as foam stabilizers, since particles tend to adsorb irreversibly at the air-water interface. Recently, we presented a nove...

This work was inspired by previous experiments which managed to establish an optimal template-dealloying route to prepare ultralow density metal foams. In this study, we propose a new analytical-numerical model of hollow-structured metal foams with structural hierarchy to predict its stiffness and strength. The two-level model comprises a main backbone and a secondary nanoporous structure. The ...