The results of this study indicate that acid etching does not alter significantly the mechanical properties of dental enamel in terms of HM, EIT, or ηIT and molecular structure according to Raman analysis.
Therefore, computational chemistry is thus necessary to get insight into the molecular structure, although according to our best knowledge no evidence of similar study for the dicyanovinyl effect on the ICT character of the model compounds selected in this study.
These compounds were not isolated due to further degradation during chromatographic processing, and their structures were not characterized due to miss matched fragmentation pattern with the available structure according to the molecular formula in Dictionary of Natural Products.
According to the molecular structures of pigments, it has been speculated that Monascus pigments are derived from polyketide and fatty acid, the biosynthesis of which share the same precursors and cofactors such as acetyl-CoA, malonyl-CoA, NADH and NADPH [ 30].
Through deconvolution of the ESR spectra, the fraction of spin-probes penetrating surfactant shells have been calculated, and differences were observed according to the surfactant molecular structures.
In contrast, films with rigid and planar molecular structure show CTE increase according to the increase of film thickness up to 40 50 μm, which then plateau for thicker films.
According to the results, the molecular structures of SD, SM, and SMX have molecular weights [M + 1]+ = 251, 265, and 254.
The molecular structures of different products can be illustrated in Figure 3 according to the molecular weight and the knowledge in the related research field [7, 13, 31, 36, 37].
The synthesized compounds were characterized by FTIR, 1H and 13C NMR, and Mass spectra and the results were in accord with the allocated molecular structures.
