Physical Properties of Soil Moisture

摘要

Proton NMR and diffusion coefficient measurements were used to study the mobility of sorbed water in Na- and Ca-montmorillonite, Na- and Ca-hectorite, and untreated kaolin. Clay samples were obtained from Ward's Natural Science Establishment, Inc. The montmorillonite and hectorite were saturated by adding a two molar chloride salt solution of either Na or Ca followed by three cycles of shaking, centrifuging, and pouring off the supernatant. Two hydrating methods were used. In the first samples were saturated and air dried while in the second saturated samples were equilibrated at a fixed moisture tension. Sample measurements taken include relaxation rate, pulse gradient diffusion, and tritium diffusion.