A FT-IR absorption analysis of vibrational properties of water encaged in NaA zeolites: evidence of a "structure maker" role of zeolitic surface.

We performed, in the O-H stretching region, Fourier-transform Infrared (FT-IR) Absorption measurements for investigating the vibrational dynamics on water confined in NaA zeolite, vs. temperature and for different hydration percentages. The spectral substructure of the O-H stretching band is explained postulating the existence of three major components centred at approximately 3290 cm(-1) (omega(1)), approximately 3470 cm(-1) (omega(2)), approximately 3590 cm(-1) (omega(3)), with different dynamical properties traced over the full T-range investigated.

FT-IR spectroscopy: a powerful tool in pharmacology.

In the present work we report a Fourier Transform Infrared (FT-IR) analysis performed on rat encephalon samples in the CH-OH vibrational stretching region (2400-3800) cm(-1), in order to reveal the presence of a very diffuse commercial benzodiazepine: VALIUM. The comparison between the spectral features of normal brain and the ones of samples with administrated substance has unambiguously showed that the CH stretching region seems not to suffer from any change for the pharmacological treatment, instead the OH band is strongly modified probably due to the presence of a new spectral contribution characteristic of diazepam molecule.

Experimental study of the hydration properties of homologous disaccharides.

To get some insight into the hydration mechanisms of homologousdisaccharides, we report measurements on trehalose, maltose, and sucroseaqueous solutions. The interest on these systems is mainly due to theextraordinary properties of disaccharides and especially of trehalose, themost effective bio-protector against freezing and dehydration. To carry outthis study we have investigated the volumetric properties of the threedisaccharide solutions, by performing density and ultrasonic velocitymeasurements at different concentration and temperature values. Whatemerges from these studies is that trehalose shows, in comparison withmaltose and sucrose, the greatest structural sensitivity to temperaturechanges and the smallest values of the partial molar volume in all theinvestigated temperature range, this circumstance being indicative of a morepacked conformational arrangement.