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The merits of employing the energy-dispersive mode for recording the dynamics of the structural changes accompanying the thermal activation of an as-prepared catalyst are illustrated by a time-resolved investigation of the dehydration of an Ni2+-exchanged Na+ zeolite Y catalyst (see Couves, Jones, Thomas, and Smith, Adv. Mater. 1990, 2, 181). EXAFS data for a model metallic nickel catalyst, collected in 500 ms, are also shown. These yield quantitatively reliable structural information, thus demonstrating the feasibility of conducting routine, dynamic studies of heterogeneous catalysts and a variety of other material under operating conditions.

The relationship between two parameters of starch damage namely enzyme susceptibility and amylose extractability was examined in starch and in hard and soft flours ground by three unconventional methods. Variations in the relationship were as great in the starch series as in the flours, demonstrating that the effects of particle properties on the efficiency of one or other method of determination were not responsible. It is suggested that the two parameters are capable of independent variation since, in a single granule complete digestibility arises following a single "once for all" event, while for extractability that etent marks the beginning of a process which can be further increased by suitable treatment. Types of starch damage can be defined in terms of ratio between extractability and digestibility and micrographs are presented which display granules afflicted by different types of damage.