Crack propagation in both porous compacts and pigmented films prepared from cellulose derivatives — a comparison of computer simulation with experimental observation

A model originally developed to simulate crack propagation in viscoplastic materials, where the micromechanism consists of void growth, has been evaluated for both pigmented films and porous compacts of cellulose derivatives. The program allows both visualization of crack growth and the calculation of crack velocity. The program is easy to use, enabling many simulations to be performed with minimum effort. The agreement with experimental observation both qualitatively and quantitatively is very good.     

Separation and identification of the Z and E isomers of 2-(3-pentenyl)pyridine by capillary electrophoresis and nuclear magnetic resonance spectroscopy

A mixture of the Z and E isomers of 2-(3-pentenyl)pyridine has been separated with baseline resolution by capillary electrophoresis. Using molecular modelling it was proposed that the smaller more rapidly migrating peak would be the Z isomer. This agreed with a 38:62 (Z/E) composition by nuclear magnetic resonance spectroscopy. The sample was also investigated by gas chromatography coupled to mass spectrometry.