Asphalt driveways are typically less expensive than concrete, costing a minimum of about $2.50 per square foot. An asphalt driveway might last just 20 years; however, while a concrete driveway can last more than 30.
Semipermeable membrane. The diffusion of water through a selectively permeable membrane is called osmosis.This allows only certain particles to go through including water and leaving behind the solutes including salt and other contaminants. In the process of reverse osmosis, thin film composite membranes (TFC or TFM) are used.
the random movement of molecules from an area of higher concentration of those molecules to an area of lower concentration. Osmosis. a special case of diffusion where water diffuses through a selectively permeable membrane from a region of higher water potential to a region of lower water potential. Permeable Membrane. a membrane that allows for diffusion of certain solutes and water.