Characterization of macroscopic disorder in a porous glass with NMR microimaging and scanning electron microscopy

Abstract

A study of the intensity fluctuations in one-dimensional NMR microimaging profiles of imbibed porous Pyrex glass filters is presented. An approach to characterize some aspects of the macroscopic randomness from the NMR microimaging profiles of this porous medium is developed. Statistical properties, such as the arithmetic and geometric means, of the distributions of peak separations between the intensity fluctuations are shown to reveal information about the pore size and the pore-to-pore distances in porous media. The intensity-intensity correlation functions of the one-dimensional NMR profiles display an interplay, as a function of length scale, among the dimensions of the porous network and its embedding space, and their respective dimensions in the projections. Corroboration of these NMR results are achieved with similar analysis of SEM two-dimensional images and their corresponding one-dimensional projections obtained with the same porous Pyrex glass. The approach developed to characterize the macroscopic randomness in these porous glass filters should prove generic for the study of other random materials.