| environ. | reverse osmosis A method of obtaining pure water from water containing a salt, as in desalination. Pure water and the salt water are separated by a semipermeable membrane and the pressure of the salt water is raised above the osmotic pressure, causing water from the brine to pass through the membrane into the pure water. This process requires a pressure of some 25 atmospheres, which makes it difficult to apply on a large scale | 反渗透 (从含盐的水中获得纯水的方法，即脱盐。纯水和盐水用半渗透性的薄膜分开并且盐水的压强高于渗透压强，这使盐水中的水通过薄膜进入纯水。这个过程需要25个气压的压强，这使得这个方法很难大规模应用。) |