ultraviolet radiation
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GC: n

S: HPS – http://hps.org/hpspublications/articles/uv.html (last access: 26 October 2013); http://uv.biospherical.com/student/page3.html (last access: 1 October 2015).

N: 1. ultraviolet radiation, that portion of the electromagnetic spectrum extending from the violet, or short-wavelength, end of the visible light range to the X-ray region. Ultraviolet (UV) radiation is undetectable by the human eye, although, when it falls on certain materials, it may cause them to fluoresce—i.e., emit electromagnetic radiation of lower energy, such as visible light. Many insects, however, are able to see ultraviolet radiation.
Ultraviolet radiation lies between wavelengths of about 400 nanometres (1 nanometre (nm) is 10−9 metre) on the visible-light side and about 10 nm on the X-ray side, though some authorities extend the short-wavelength limit to 4 nm. In physics, ultraviolet radiation is traditionally divided into four regions: near (400–300 nm), middle (300–200 nm), far (200–100 nm), and extreme (below 100 nm). In biology, three conventional divisions have been observed: near (400–315 nm), which is absorbed relatively poorly by organisms; actinic (315–200 nm), which is absorbed most readily by organic matter and thus has the greatest effects on organisms; and vacuum (less than 200 nm), which is absorbed by most substances, including oxygen in the air (and below 100 nm nitrogen), and so is of little use in biological experimentation.
2. Ultraviolet (UV) radiation is defined as that portion of the electromagnetic spectrum between x rays and visible light, i.e., between 40 and 400 nm (30–3 eV). The UV spectrum is divided into Vacuum UV (40-190 nm), Far UV (190-220 nm), UVC (220-290 nm), UVB (290-320), and UVA (320-400 nm). The sun is our primary natural source of UV radiation.

S: 1. EncBrit. 2. HPS http://hps.org/hpspublications/articles/uv.html (last access: 26 October 2013).

SYN: 1. UV radiation. 2. ultra-violet radiation, UV, U.V., UV radiation, ultraviolet, ultraviolet light, ultraviolet ray. 3. ultra-violet radiation, UV, UV radiation, ultraviolet light, ultraviolet, ultraviolet rays.

S: 1. SCUVR p. 7. 2. TERMIUM PLUS (last access: 26 October 2013). 3. GDT (last access: 26 October 2013).

CR: solar radiation