Determination of moisture fraction in wood by mobile NMR device

Published Date
December 2004, Vol.171(2):364–372, doi:10.1016/j.jmr.2004.09.014

Author 

C. Casieri ^a

L. Senni ^b

M. Romagnoli ^c

U. Santamaria ^d

F. De Luca ^b,,

aINFM-CRS SOFT and Dipartimento di Fisica, Università di L’Aquila, V. Vetoio 10, I-67010 Coppito, L’Aquila, Italy

bINFM-CRS SOFT and Dipartimento di Fisica, Università “La Sapienza,” P.le A. Moro 2, I-00185 Rome, Italy

cDipartimento di Tecnologie, Ingegneria Scienze dell’Ambiente e delle Foreste (DAF), Università della Tuscia, V. San Camillo de Lellis, I-01100 Viterbo, Italy

• dLaboratori Scientifici dei Musei Vaticani, Città del Vaticano, Italy

Received 22 July 2004. Revised 17 September 2004. Available online 14 October 2004. 

Abstract

A mobile NMR probe has been used as a non-destructive and non-invasive tool for water content analysis on wood samples. The porosity index, express as the fraction of the sensitivity volume of the probe occupied by water, is here proposed as an alternative to the moisture content index, namely the amount of water mass with respect to the mass of dried sample. In principle the method can be applied to any kind of porous media that has not detectable proton signal from the rigid matrix as, for instance, in building materials. In wood, where proton signal can be detected also from cellulose and others macromolecular components, some considerations and artifices are here proposed for eliminating this contribution. The method has allowed performing moisture volume fraction analysis on wood samples characterized by different wood species, cutting and moisture contents. The NMR data of moisture detection as volume fraction have successfully been compared with those obtained by the gravimetric method.

Keywords

NMR in wood

Wood moisture contents

Single-sided NMR

NMR porosity

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• * 
  Corresponding author

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