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This book presents data on thermal relaxation properties of chitosan neutralized and non-neutralized films as a function of water content using dynamical mechanical analysis and dielectric spectroscopy in the temperature range from 20 to 250°C. Three relaxation processes have been observed in different temperature and frequency ranges. For the first time, the low frequency á-relaxation associated with the glass-rubber transition, which relates to a plasticizing effect of water, has been detected by this technique in both chitosan forms in the temperature range 20-70°C and for moisture contents between 0.5 to 10 wt%. This book discusses various relaxation processes in chitosan films.

Nuclear magnetic resonance (NMR) is widely used across many fields because of the rich data it produces, and some of the most valuable data come from the study of nuclear spin relaxation in solution. While described to varying degrees in all major NMR books, spin relaxation is often perceived as a difficult, if not obscure, topic, and an accessible, cohesive treatment has been nearly impossible to find.Collecting relaxation theory, experimental techniques, and illustrative applications into a single volume, this book clarifies the nature of the phenomenon, shows how to study it, and explains why such studies are worthwhile. Coverage ranges from basic to rigorous theory and from simple to sophisticated experimental methods, and the level of detail is somewhat greater than most other NMR texts. Topics include cross-relaxation, multispin phenomena, relaxation studies of molecular dynamics and structure, and special topics such as relaxation in systems with quadrupolar nuclei and paramagnetic systems.Avoiding overly demanding mathematics, the authors explain relaxation in a manner that anyone with a basic familiarity with NMR can follow, regardless of their specialty. The focus is on illustrating and explaining the physical nature of the phenomena, rather than the intricate details. Nuclear Spin Relaxation in Liquids: Theory, Experiments, and Applications forms useful supplementary reading for graduate students and a valuable desk reference for NMR spectroscopists, whether in chemistry, physics, chemical physics, or biochemistry.