Due to its non-destructive characteristic, nuclear magnetic resonance (NMR) spectroscopy was used to study the fiber saturation point (FSP) of Pseudotsuga menziesii before and after heat treatment. The bound water amount in saturated wood cell wall was determined by analysis of T2 relaxation time distributions measured using GPMG (Carr-Purcell-Meiboom-Gill) sequence at -3℃ and 25℃. Results showed that the FSP of Pseudotsuga menziesii treated with various temperatures are 32.82% (180℃), 29.40% (200℃), 24.90% (220℃) and 38.76% (untreated), which indicate that FSP of Pseudotsuga menziesii decreases with increased heat treatment temperature. This study reflects that NMR could provide detailed information about wood water distribution rapidly and efficiently.
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