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The effect of proteins upon diethyl ether extraction of phospholipids from aqueous dispersions has been investigated as a model for elucidating lipid‐protein interactions in the more complex membrane systems. Mixed phospholipids having a net anionic charge or purified lecithin (a zwitterion) are extracted from water dispersions into ether only after addition of salts. Basic proteins (lysozyme and cytochromec), by ionically binding phospholipids, allow extraction. Phospholipids are extracted together with the proteins in the form of neutralized lipid‐protein complexes. On the other hand, lipid depleted mitochondria (a hydrophobic protein residue after acetone extraction of mitochondria), after reconstitution with phospholipids, do not allow phospholipid extraction unless salts or basic proteins also are added to the system. This observation indicates that, in reconstituted membranes, the phospholipids are largely in the bilayer form with the polar heads still charged and susceptible to ether extraction only after neutralization with salts or basic proteins.

The thermal performance of latent heat thermal energy storage (LHTES) systems considerably depends on thermal conductivity of adopted phase change materials (PCMs). To increase the low thermal conductivity of these materials, pure PCMs can be loaded with metal foams. In this study, the melting process of pure and metal-foam loaded phase change materials placed in a rectangular shape case is experimentally investigated by imposing a constant heat flux at the top. Two different paraffin waxes with melting point of about 35°C are tested. The results obtained with pure PCM are compared with those achieved from the use of PCM combined with two different porous metals: a 10 PPI aluminum foam with 96% porosity and a 20 PPI copper foam with 95% porosity. The results demonstrate how metal foams lead to a significant improvement of conduction heat transfer reducing significantly the melting time and the temperature difference between the heater and PCM.