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A UV-Vis spectrophotometer is an analytical instrument that measures the amount of ultraviolet (UV) and visible light that is absorbed by a sample. It is a widely used technique in chemistry, biochemistry, and other fields, to identify and quantify compounds in a variety of samples.
Ultraviolet-visible (UV-vis) spectroscopy involves energy levels that excite electronic transitions. Absorption of UV-vis light excites molecules that are in ground-states to their excited-states. [5] Visible region 400–700 nm spectrophotometry is used extensively in colorimetry science. It is a known fact that it operates best at the range ...
Developed by Bausch & Lomb and launched in 1953, the Spectronic 20 was the first low-cost spectrophotometer. [5] It rapidly became an industry standard [7] due to its low cost, durability and ease of use, [8] and has been referred to as an "iconic lab spectrophotometer". [9] Approximately 600,000 units were sold over its nearly 60 year ...
This is similar to the situation in a hydrogen flame. Arc lamps made with ordinary light-hydrogen provide a very similar UV spectrum to deuterium, and have been used in UV spectroscopes. However, lamps using deuterium have a longer life span and an emissivity (intensity) at the far end of their UV range which is three to five times that of an ...
[2]: 151 [34] [35] All modern UV–Vis spectrophotometer are built on the same basic principles as the DU spectrophotometer. [29] Diagram of Model DU optical system, Beckman manual, 1954 "Light from the tungsten lamp is focused by the condensing mirror and directed in a beam to the diagonal slit entrance mirror.
This arrangement is the most suitable when the compound of interest is deposited or adsorbed on the working electrode, because it provides information about all processes occurring on the electrode surface. [7] UV-Vis absorption SEC in normal arrangement can be performed using both transmission and reflection phenomena. [11] Normal transmission
If the instrument is designed to measure the spectrum on an absolute scale rather than a relative one, then it is typically called a spectrophotometer. The majority of spectrophotometers are used in spectral regions near the visible spectrum. A spectrometer that is calibrated for measurement of the incident optical power is called a ...
Absorption photometers for work in aqueous solution work in the ultraviolet and visible ranges, from wavelength around 240 nm up to 750 nm. The principle of spectrophotometers and filter photometers is that (as far as possible) monochromatic light is allowed to pass through a container (cell) with optically flat windows containing the solution ...