A Wavelet Filtering Method for Measuring Oil Content of Fiber with Low-Field NMR

Abstract

Abstract:

A new wavelet transform-based method for measuring the oil content of fiber with low-field NMR was introduced. Firstly, free induction decays (FID) of the standard fibers were collected and used to calculate the calibration curve through linear fitting. Secondly, the signals of the testing fiber were collected with different numbers of averages, and wavelet soft threshold was used to filter each of the collected signals. Finally, the oil content of the fiber was calculated by comparing the filtered NMR signals with the calibration curve. Practical applications were used to validate the effectiveness of the new method.

Key words: NMR, wavelet filtering, soft threshold, oil content of fiber, detection

CLC Number:

O482.53

LI Xin-Jun, ZHANG Ying-Li, YANG Pei-Qiang, NIE Sheng-Dong. A Wavelet Filtering Method for Measuring Oil Content of Fiber with Low-Field NMR[J]. Chinese Journal of Magnetic Resonance, 2012, 29(1): 32-41.

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