SPATIALLY-RESOLVED PORE-SIZE DISTRIBUTIONS BY NMR

We have developed a novel method of determining median pore size and p ore size distributions as a function of spatial position inside a poro us sample. Pore sizes have been measured with one-, two- and three-dim ensional spatial resolutions, using nuclear magnetic resonance (NMR) c ryoporometry in conjunction with magnetic resonance imaging techniques . NMR cryoporometry is a method of measuring pore sizes and pore size distributions in the range of less than 40 Angstrom to over 2000 Angst rom pore diameter, by the technique of freezing a liquid in the pores and measuring the melting temperature by NMR. Since the melting point is depressed for crystals of small size, the melting point depression gives a measurement of pore size.