Spectral features, synchrotron-based

NEXAFS is a synchrotron-based spectroscopic tool routinely used as a complementary technique with XPS for surface characterizations. This method probes the adsorption of X-rays by the excitation of core (K-shell) electrons into unoccupied electronic states near the ionization limit. Subsequent emission of Auger electrons results in the formation of an NEXAFS electron yield the observed spectmm. Because the source of Auger electrons can extend only up to 10 nm and the spectral peak positions and intensities are directly related to the nature of unoccupied electronic states, NEXAFS spectroscopy provides an important tool for studying stmctural and chemical features of various surface thin films and coatings (Hemraj-Benny et al., 2006 Hahner, 2006). 

The FTIR synchrotron spectroscopy of rat glioma cells treated with cisplatin revealed changes in the spectra from which the ANN analysis was able to correctly classify cisplatin-exposed or control cells. The spectral features identified as statistically significant for this classification were consistent with features identified by examination of averaged spectra from the two conditions. Moreover the neural network was able to correctly classify an independent test set of spectra based on a model that examined only the profile of the asymmetric phosphodiester stretching vibration band. 

Abstract This chapter describes a general introduction of the Mossbauer spectroscopy. What is the Mossbauer effect and what is the characteristic feature of the Mossbauer spectroscopy These questions are answered briefly in this chapter. Mossbauer spectroscopy is based on recoilless emission and resonant absorption of gamma radiation by atomic nuclei. Since the electric and magnetic hyperfine interactions of Mossbauer probe atom in solids can be described from the Mossbauer spectra, the essence of experiments, the hyperfine interactions and the spectral line shape are discussed. In addition, the experiments and the new resonance technique with synchrotron radiation have been also briefly described. 

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