In this paper, new results obtained by quasi elastic and inelastic neutron scattering experiments performed on vitamin C (L-ascorbic acid)/H2O mixtures are reported. The data analysis of the QENS measurements. by a separation of the diffusive dynamics of hydrated L-ascorbic acid from that of water, furnishes quantitative evidences of a random jump diffusion motion of vitamin C and shows that the water dynamics is strongly affected by the presence of L-ascorbic acid. Concerning the INS experiment, we are able, through the behaviour of neutron spectra across the glass transition temperature (T-g approximate to 233 K for the vitamin C/water system), to collocate the investigated system in the Angell "strong- fragile" scheme. (C) 2002 Elsevier Science B.V. All rights reserved.
Quasi elastic and inelastic neutron scattering study of vitamin C aqueous solutions
Micali N
2002
Abstract
In this paper, new results obtained by quasi elastic and inelastic neutron scattering experiments performed on vitamin C (L-ascorbic acid)/H2O mixtures are reported. The data analysis of the QENS measurements. by a separation of the diffusive dynamics of hydrated L-ascorbic acid from that of water, furnishes quantitative evidences of a random jump diffusion motion of vitamin C and shows that the water dynamics is strongly affected by the presence of L-ascorbic acid. Concerning the INS experiment, we are able, through the behaviour of neutron spectra across the glass transition temperature (T-g approximate to 233 K for the vitamin C/water system), to collocate the investigated system in the Angell "strong- fragile" scheme. (C) 2002 Elsevier Science B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
