Journal of Wood Science

, Volume 55, Issue 1, pp 69–73 | Cite as

Evaluation of moisture content distribution in wood by soft X-ray imaging

  • Takashi TanakaEmail author
  • Stavros Avramidis
  • Satoshi Shida


A technique for nondestructive evaluation of moisture content distribution in Japanese cedar (sugi) during drying using a newly developed soft X-ray digital microscope was investigated. Radial, tangential, and cross-sectional samples measuring 100 × 100 × 10 mm were cut from green sugi wood. Each sample was dried in several steps in an oven and upon completion of each step, the mass was recorded and a soft X-ray image was taken. The relationship between moisture content and the average grayscale value of the soft X-ray image at each step was linear. In addition, the linear regressions overlapped each other regardless of the sample sections. These results showed that soft X-ray images could accurately estimate the moisture content. Applying this relationship to a small section of each sample, the moisture content distribution was estimated from the image differential between the soft X-ray pictures obtained from the sample in question and the same sample in the oven-dried condition. Moisture content profi les for 10-mm-wide parts at the centers of the samples were also obtained. The shapes of the profiles supported the evaluation method used in this study.

Key words

Nondestructive evaluation Soft X-ray Moisture content distribution Drying Sugi 


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Copyright information

© The Japan Wood Research Society 2008

Authors and Affiliations

  • Takashi Tanaka
    • 1
    Email author
  • Stavros Avramidis
    • 2
  • Satoshi Shida
    • 1
  1. 1.Biomaterial Sciences Department, Graduate School of Agricultural and Life SciencesThe University of TokyoTokyoJapan
  2. 2.Department of Wood ScienceUniversity of British ColumbiaVancouverCanada

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