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The research has been focusing on some connection between the chemical composition of the papers obtained by Fourier transform infrared (FTIR) spectroscopy and the nature of the fillers, determined by energy dispersion X-ray fluorescence (EDXRF) spectroscopy. The present paper corroborates the FTIR and EDXRF results obtained for some historical papers from books of the XIX-th and XX-th centuries, from private collections. These analytical results allowed a first approximation of technological paper composition and of the age determination of the samples. This analytical method can elaborate some properly methods for paper documents preservation, taking into account the aging and degradation processes of the historical paper. [ABSTRACT FROM AUTHOR]

This review describes the application of selected spectroscopic techniques to the world of cultural heritage conservation. In recent times, science and technology have been applied to the world of cultural heritage, conservation and preservation. In this field, spectroscopic techniques represent one of the most powerful tools to investigate the structure of all the materials constituting the “cultural object.” In particular, this survey will consider the “status of art” in the field of some important spectroscopic techniques for the characterization of the following works of art: easel paintings, paper and ink artifacts, stone monuments and wall paintings, and archaeological ceramics. The spectroscopic techniques that have been used and will be reviewed are Fourier transform infrared spectroscopy and also coupled with the microscope, X-ray fluorescence spectroscopy, proton-induced X-ray emission spectroscopy, ultraviolet, visible and fluorescence spectroscopy, Raman spectroscopy, and Mossbauer spectroscopy. [ABSTRACT FROM AUTHOR]

Zwitterions are aqueous solvated molecules simultaneously possessing one negatively and one positively charged site. Although electroneutral, the environmental interaction of zwitterions with other ionic species is likely to differ significantly from the behavior of comparable electroneutral species without charged sites. Amino acids, the zwitterionic species that have received the most historical scrutiny, are believed to possess at least four microscopic acidity constants: k[sub a] = [H[sup +]] [[sup +]H[sub 3]NRCOO[sup -]]/[[sup +]H[sub 3]NRCOOH], k[sub b] = [H[sup +]] [H[sub 2]NRCOOH]/[[sup +]H3NRCOOH], k[sub c] = [H[sup +]] [H[sub 2]NRCOO[sup -]]/[[sup +]H[sub 3]NRCOO[sup -]], and k[sub d] = [H[sup +]] [H[sub 2]NRCOO-]/[H[sub 2]NRCOOH]. Unfortunately, due to their comparable energetics, these microscopic acidity constants cannot be discerned using standard potentiometric titration procedures. In response, experimentally observable macroscopic constants (K[sub 1] and K[sub 2]) have historically been related to the microscopic constants with the following relationships: K[sub 1] = k[sub a] + k[sub b] and 1/K[sub 2] = 1/k[sub c] + k[sub d]. It will be demonstrated that these equations are approximations suitable for restricted pH ranges and that more exact expressions can be derived: K[sub 1] = k[sub a] + k[sub b] + k[sub c]k[sub a]/[H[sup +]] + k[sub d]k[sub b]/[H[sup +]] and 1/K[sub 2] = 1/k[sub d] + 1/k[sub c] + [H[sup +]]/k[sub a]k[sub c] + [H[sup +]]/k[sub b]k[sub d]. [ABSTRACT FROM AUTHOR]