The NIR region showed some differences between untreated Tiffany Elsa Peretti Teardrop Earrings treated samples at approximately 1164, 1187, 1364, and 1412 nm in the first derivative spectra from the sapwood samples. This is consistent with Via et al. (2008) who found wavelengths between 1115 and 1195 nm, 1335 and 1415 nm, and 1655 and 1685 nm to be most influenced by blue stain. Tiffany Elsa Peretti Teardrop necklace heartwood samples had very few variations in the NIR region. The absence of significant differences above 1450 nm that correspond to bands associated with cellulose and lignin (Via et al. 2006, Schimleck et al. 2004) suggests that the chemistry of these critical wood components was not greatly affected by either short light exposure Tiffany Cushion short bleaching treatments. FTIR spectra of blue-stained wood are affected strongly by the functional groups of wood components, but little affected by fungal melanins (Humar et al. 2008). Average FTIR spectra from the four most extreme treatment groups (untreated, exposed to hypochlorite bleaching for 20 minutes, Tiffany Elsa Peretti Teardrop pendant to intense light for 20 minutes, or exposed to hypochlorite bleaching for 20 minutes followed by intense light for 20 min.) are shown in Figures 9 and 10. In the sapwood, the peak at 1740 cm^sup -1^ was only observed in the untreated samples. This has been attributed to unconjugated carbonyl stretching primarily from hemicelluloses (Chow 1972, Tolvaj and Faix 1995) and suggests that both the bleaching and light exposure may affect hemicellulose functional groups.
Commentaires
Il n'y a aucun commentaire sur cet article.