Ozone vacuum-ultraviolet (VUV) ozone generators, employ a light source that generates a narrow-band ultraviolet light, a subset of that produced by the Sun. The Sun's UV sustains the ozone layer in the stratosphere of Earth. UV ozone generators use ambient air for ozone production, no air prep systems are used (air dryer or oxygen concentrator), therefore these generators tend to be less expensive. However UV ozone generators usually produce ozone with a concentration of about 0.5% or lower which limits the potential ozone production rate. Another disadvantage of this method is that it requires the ambient air (oxygen) to be exposed
The Languages of Tolkien's Middle-earth are all the languages in "The Lord of the Rings", except for Entish (of which no real examples are given; the closest we get is Elvish words strung together in an Entish manner, a sort of Ent pidgin). The Languages of Tolkien's Middle-earth The Languages of Tolkien's Middle-earth is a book on the languages of Middle-earth by Ruth S. Noel. The first edition, entitled "The Languages of Middle-earth", was published in 1974 by Mirage Press, Baltimore. The revised version was published in 1980 by Houghton Mifflin. Ruth S. Noel, also known as Atanielle Annyn Noel, is the author of "The