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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.
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.
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 ...
Cary Model 14B Recording Spectrophotometer (front, details almost identical to Model 14) Cary Model 14 Recording Spectrophotometer (back, open) The Cary Model 14 UV-VIS Spectrophotometer was a double beam recording spectrophotometer designed to operate over the wide spectral range of ultraviolet, visible and near infrared wavelengths (UV/Vis/NIR).
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 ...
The variable UV-Vis absorbance detector's optical bench is showing how the flow cell is positioned after the optical system, including the monochromator, which typically has a physical slit and a moving grating, so it is illuminated by a selected wavelength, reaching a photo-diode.
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 ...