Nutrition law of the minimum is considered an essential plant nutrient if the plant cannot complete its full life cycle without it. There are 16 essential plant soil nutrients, besides the three major elemental nutrients carbon and oxygen that are obtained by photosynthetic plants from carbon dioxide in air, and hydrogen, which is obtained from water. Plants uptake essential elements from the soil through their roots and from the air (consisting of mainly nitrogen and oxygen) through their leaves. Green plants obtain their carbohydrate supply from the carbon dioxide in the air by the process of photosynthesis. Carbon and oxygen are
Carbon dioxide laser as 5,000° C, producing bright thermal radiation. The common plastic poly (methyl methacrylate) (PMMA) absorbs IR light in the 2.8–25 µm wavelength band, so CO lasers have been used in recent years for fabricating microfluidic devices from it, with channel widths of a few hundred micrometers. Because the atmosphere is quite transparent to infrared light, CO lasers are also used for military rangefinding using LIDAR techniques. CO lasers are used in spectroscopy and the Silex process to enrich uranium. The Soviet Polyus was designed to use a megawatt carbon-dioxide laser as an in-orbit weapon to destroy SDI satellites. Carbon dioxide