Silica aerogels prepared by the sol-gel process are often used as solid desiccants in enthalpy wheels for dehumidifying ventilation air in air-conditioning systems. These hygroscopic materials have good moisture adsorption and desorption characteristics due to their porous structure. The current study is focused on the evaluation of the mass diffusivity of solid silica aerogels and silica aerog...

Many wounds heal slowly and are difficult to manage. Therefore Negative Pressure Wound Therapy (NPWT) was developed where polymer foams are applied and a defined negative pressure removes wound fluid, reduces bacterial burden and increases the formation of granulation tissue. Although NPWT is used successfully, its mechanisms are not well understood. In particular, different NPWT dressings were...

Synthesis and characterization of novel Tea Tree Oil (TTO) loaded antibacterial polyurethane rigid foams using two distinct methods is reported. In the first method, 3-aminopropyltriethoxysilane (APTS) functionalized mesoporous silica was used as carrier TTO for preparing amino-functionalized (TTO-NH2-MCM-41). second one, encapsulated by via sol-gel then APTS, nanocontainers with amino groups (...

Acoustic measurements provide convenient non-invasive means for the characterisation of materials. We show here for the first time how a commercial impedance tube can be used to provide accurate measurements of the velocity and attenuation of acoustic waves in liquid foams, as well as their effective "acoustic" density, over the 0.5-6kHz frequency range. We demonstrate this using two types of l...

The mechanical behaviour of a new type of open-cell foam made by a thermally induced phase separation (TIPS) process was investigated. Foams made by the TIPS process are characterized by cell sizes which are 10-100 times smaller than conventional foam materials. In this work, the linear elastic modulus of these foams in dynamic tension/compression was measured. A comparison was made with the th...

In this study, at the first stage, the rupture criterion of bubbles wall in Aluminum metal foam liquid was investigated by using Lattice Boltzmann. The two phases modeling were accomplished by using a modified Shan-Chen model. This model was run for several bubbles in A356+3wt.%SiC melt system. Then, bubbles morphologies (virtual metallographic) for A356+3wt.%SiC foams were simulated. Results s...

Foam materials based on metal and several polymers were transformed so that their cellular architectures became re-entrant, ie. with inwardly protruding cell ribs. Foams with re-entrant structures exhibited negative Poisson's ratios as well as greater resilience than conventional foams. Foams with negative Poisson's ratios were prepared using different techniques and materials and their mechani...

Fabrication of metallic foams by sintering metal powders mixed with thermally degradable compounds is of interest for numerous applications. Compounds releasing gaseous nitrogen, minimizing interactions between the formed gases and metallic foam by diluting other combustion products, were applied. Cysteine and phenylalanine, were used as gas releasing agents during the sintering of elemental Fe...