Abstract:
Based on studies on the characteristics of ultraviolet-visible absorption spectra, ESR and
13C NMR spectra, the three dimensional fluorescence spectra of natural and treated ambers with fluorescence are studied by using the three dimensional fluorescence spectrophotometer. The results indicate that the three dimensional fluorescence spectrum with the main peak of 346 nm(λ
Ex)/437 nm(λ
Em) is closely associated with emission of conjugated double bonds molecular with the π→π
* transition energy level in natural amber. The research results also prove tentatively that the local spliting of some chemical bonds of the carbon functional group in heat treated amber is the main cause of blue shift 354 nm(λ
Ex)/415 nm(λ
Em) of the main peak of the three dimensional fluorescence spectrum. Many luminescence centers, which have different strength in the three dimensional fluorescence spectrum of heat-filling treated amber, are closely related to the unequal amounts of incorporated unsaturated ester copolymer and aromatic compound from foreign sources by heat-filling treatment. The three dimensional fluorescence spectrum lends itself to representing carbon functional groups enveloping each other in heat-filling treated amber, and it has an important representative significance for identifying the natural and heat-filling treated amber and artificially resin.