Abstract: Water vapor is introduced into an inlet air stream (16) of an engine (12), for example, by a pervaporation process through a non-porous hydrophilic membrane (18). A water reservoir (20), which can contain contaminated water, provides a vapor pressure gradient across the hydrophilic membrane (18) into the inlet air stream (16), while the rate of delivery of the water vapor to a cylinder (38-40) is self-regulated by the rate of flow of air across the membrane. The hydrophilic membrane (18) therefore also filters the water from the water reservoir (20) to an extent that pure water vapor is provided to the air inlet stream (16). Delivery of water vapor can nevertheless be controlled using a hood (26) that slides over the hydrophilic membrane to limit its exposed surface area.

Abstract: A method of modifying the growth of plant roots is provided in which the roots are grown in proximity to a membrane from which water is released during the growth of the roots, wherein the membrane is a hydrophobic porous membrane or a hydrophilic non-porous membrane. The method may also be used to collect materials exuded from plant roots by growing the plant roots in a growing medium that is surrounded by a membrane so that moisture is released into the growing medium from the membrane while materials exuded from the plant roots are retained within the growing medium by the membrane, wherein the membrane is a hydrophobic porous membrane or a hydrophilic non-porous membrane.