Moisture Content in Drying Wood Using Direct Scanning Gamma-Ray Densitometry


  • John R. Davis
  • Jugo Ilic
  • Peter Wells


Gamma-ray attenuation, wood densitometry, moisture content, shrinkage


The distribution of moisture content in specimens of Eucalyptus regnans at various stages of drying from the green state has been measured using a direct scanning gamma-ray densitometer. Densitometry results obtained using 59.5 keV gamma-ray photons were compared with data obtained from matched specimens using a conventional slicing and weighing technique. Preliminary results of a shrinkage distribution analysis are presented for the first time. A detailed discussion of the theoretical and experimental aspects of the scanning densitometry technique is given together with a description of the instrument constructed for this work.


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