Nitrogen from a gaseous phase is to be diffused into pure iron at 700°C. If the surface concentration is maintained at 0.15 wt% N, what will be the concentration (in weight percent) 1.7 mm from the surface after 5.4 h? The diffusion coefficient for nitrogen in iron at 700°C is 1.0 × 10-10 m2/s.

Describe one experiment in which the glass transition temperature and melting temperature of a totally amorphous thermoplastic material can be determined. show the relevant experimental results in a diagram which should be properly annotated with the two temperatures clearly marked. what is likely to happen to the curve in the diagram if the amorphous polymer is replaced by a thermosetting type?