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UV-Vis can be used to monitor structural changes in DNA. [8] UV-Vis spectroscopy is routinely used in analytical chemistry for the quantitative determination of diverse analytes or sample, such as transition metal ions, highly conjugated organic compounds, and biological macromolecules. Spectroscopic analysis is commonly carried out in ...
A gamma-ray burst in the Milky Way, if close enough to Earth and beamed toward it, could have significant effects on the biosphere. The absorption of radiation in the atmosphere would cause photodissociation of nitrogen, generating nitric oxide that would act as a catalyst to destroy ozone. [22] The atmospheric photodissociation
Photoexcitation is the first step in a photochemical process where the reactant is elevated to a state of higher energy, an excited state.The first law of photochemistry, known as the Grotthuss–Draper law (for chemists Theodor Grotthuss and John W. Draper), states that light must be absorbed by a chemical substance in order for a photochemical reaction to take place.
Intrinsic DNA fluorescence is the fluorescence emitted directly by DNA when it absorbs ultraviolet (UV) radiation. It contrasts to that stemming from fluorescent labels that are either simply bound to DNA or covalently attached to it, [1] [2] widely used in biological applications; such labels may be chemically modified, not naturally occurring, nucleobases.
Diffuse reflectance spectroscopy, or diffuse reflection spectroscopy, is a subset of absorption spectroscopy.It is sometimes called remission spectroscopy.Remission is the reflection or back-scattering of light by a material, while transmission is the passage of light through a material.
The specificity of absorption spectra allows compounds to be distinguished from one another in a mixture, making absorption spectroscopy useful in wide variety of applications. For instance, Infrared gas analyzers can be used to identify the presence of pollutants in the air, distinguishing the pollutant from nitrogen, oxygen, water, and other ...
With the aid of these rules the UV absorption maximum can be predicted, for example in these two compounds: [8] In the compound on the left, the base value is 214 nm (a heteroannular diene). This diene group has 4 alkyl substituents (labeled 1,2,3,4) and the double bond in one ring is exocyclic to the other (adding 5 nm for an exocyclic double ...
The vast majority of liquid chromatographic systems are equipped with ultraviolet (UV) absorption detectors. The most common UV-Vis detectors used are variable wavelength detectors (VWD), photo diode array detectors (PDA), and diode array detectors (DAD). [4] Variable wavelength detectors decide in advance which wavelength is needed for the ...