Directions. 1. Wash and cut the vegetables. Blanch the asparagus spears in boiling water for 1 minute and then plunge into ice water to stop the cooking and keep them bright green and crisp. 2. Start by lining the edge of the serving tray using the red-leaf lettuce. Next layer the celery followed by the baby carrots.
Directional control valve. Directional control valves are one of the most fundamental parts in hydraulic machinery as well as pneumatic machinery. They allow fluid flow into different paths from one or more sources. They usually consist of a spool inside a cylinder which is mechanically or electrically controlled.
Updated April 12, 2017. Directional selection is a type of natural selection that favors one extreme phenotype over the mean or another extreme. This phenomenon is usually seen in environments that have changed over time. Changes in weather, climate, or food availability lead to directional selection.