SINGLE-SIDED NMR FOR MOISTURE CONTENT EVALUATION OF COMPOSITES

THE NUCLEAR MAGNETIC RESONANCE BEHAVIOR OF HYDROGEN NUCLEI IN LIQUID WATER AND WATER TRAPPED IN THE PORES OF MATERIALS IS DRAMATICALLY DIFFERENT THANTHAT OF HYDROGEN NUCLEI IN SOLIDS. SPECIFICALLY, THE RELAXATION RATES OF THE NUCLEI IN THE TWO CASES ARE TYPICALLY DIFFERENT BY TWO TO THREE ORDERS OF MAGNITUDE. DURING PHASE I, WE PROPOSE TO EVALUATE THE USE OF THIS DIFFERENCE FOR DETECTING AND MEASURING THE AMOUNT OF WATER WHICH HAS BEEN ABSORBED INTO COMPOSITE MATERIALS. THE EVALUATION WILL INCLUDE MEASUREMENTS ON SPECIFIC MATERIALS OF INTEREST, AND ESTIMATES OF EXPECTED SIGNAL-TO-NOISE VALUES BASED ON THE RESULTS OF SAMPLE MATERIALS. IN PHASE I WE WILL ALSO EVALUATE THE APPLICABILITY OF SOME NEWLY DEVELOPED NMR TECHNIQUES FOR USE IN THIS APPLICATION.