Ultraviolet-visible absorption spectroscopy is a method for qualitative, quantitative, or structural analysis of substances based on measuring the absorption spectrum of a substance in the 200-800 nm spectral region or the absorbance value at a specified wavelength. This method is also called ultraviolet-visible spectrophotometry. The ultraviolet-visible absorption spectrum belongs to the electronic spectrum, which is generated by the transition of the outer electrons or valence electrons of polyatomic molecules. This spectrum can be used for the analysis and research of compounds containing unsaturated bonds, especially compounds containing conjugated systems. Although the UV absorption spectrum can basically only reflect the characteristics of the chromophore and auxiliary chromophore in the molecule, rather than reflecting the characteristics of the entire molecule, it still plays an important role in the determination of the structure of the compound. UV-visible absorption spectroscopy for quantitative analysis is the most important use of this method. The method of using colored solutions to absorb visible light for quantitative analysis is called colorimetric analysis. This is one of the oldest analytical methods and it is still widely used today. Since the introduction of the world's first mature ultraviolet-visible spectrophotometric commercial instrument in the world in 1945 by the American company Beckman, the ultraviolet-visible spectrophotometric method has brought rapid development. The spectrum area used extends from the visible region to the near-ultraviolet region, which is not only suitable for the measurement of colored solutions, but also for the absorption of colorless components in the ultraviolet region, providing a convenient method for the analysis of many inorganic and organic substances. . Multipurpose Diaper Backpack are becoming more and more popular as regular items for babies and parents. Whether it is a long-distance travel or a short trip, Diaper Bag provides important convenience for babies and parents. The popularity of Diaper Bags has caused new parents to pay more attention to infant travel, not only psychologically but also physical changes, with great significance. Multipurpose Diaper Backpack Baby Diaper Backpack,Diaper Backpack,Baby Backpack Diaper Bag,Multipurpose Diaper Backpack JOYBABIES PRODUCT CO.,LTD. , https://www.my-joybabies.com
Brief Introduction of Ultraviolet-Visible Absorption Spectrometry for Structure Determination of Laboratory Compounds