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( Ultraviolet)
Ultraviolet (UV) light is electromagnetic radiation with a wavelength shorter than that of visible light, but longer than x-rays, in the range 400 nm to 10 nm, and energies from 3 eV to 124 eV. It is so named because the spectrum consists of electromagnetic waves with frequencies higher than those that humans identify as the color violet. UV light is found in sunlight and is emitted by electric arcs and specialized lights such as black lights. As an ionizing radiation it can cause chemical reactions, and causes many substances to glow or fluoresce. Most people are aware of the effects of UV through the painful condition of sunburn, but the UV spectrum has many other effects, both beneficial and damaging, on human health. The discovery of UV radiation was intimately associated with the observation that silver salts darken when exposed to sunlight. In 1801 the German physicist Johann Wilhelm Ritter made the hallmark observation that invisible rays just beyond the violet end of the visible spectrum were especially effective at darkening silver chloride-soaked paper. He called them "de-oxidizing rays" to emphasize their chemical reactivity and to distinguish them from "heat rays" at the other end of the visible spectrum. The simpler term "chemical rays" was adopted shortly thereafter, and it remained popular throughout the 19th century. The terms chemical and heat rays were eventually dropped in favor of ultraviolet and infrared radiation, respectively.[1] The name means "beyond violet" (from Latin ultra, "beyond"), violet being the color of the shortest wavelengths of visible light. UV light has a shorter wavelength than that of violet light.
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Ultraviolet Subcategories
Ultraviolet Articles
Sunless Tanning: How to get the most out of ultraviolet radiation tanning? by Ursula McLean
Sunless tanning is in very much vogue, how to get tanned artificially is each person’s own choice. Many people make the choice of ultraviolet radiation to get that near natural tan.
What are the benefits associated with the ultravio...
How to Protect yourself from Ultraviolet rays from the sun by Drago Marx
Everyone can have skin problems due to there are many natural and unhealthy ingredients that can cause your skin to be unhealthy. Many people experience dry or cracking skin. Many teenagers have very oily skin and are acne prone. And if you are someo...
UV Radiation and Your Skin by John Grimes
UV Radiation and Your Skin
skin, care, radiation, uv, uvb, uva, uvc, skin cancer, damage, ultraviolet, protection,
As you age, your skin begins to show signs of the wear and tear of time. Much of this aging is caused by UV radiation ...
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