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Title: Equivalent circuit modeling of wood at 12% moisture content

Source: Wood and fiber science. Vol. 39, no. 4 (2007): Pages 556-565.

Author(s)Zelinka, Samuel L.; Stone, Donald S.; Rammer, Douglas R.

Publication Year: 2007  View PDF »

Category: Journal Articles
Associated Research Project(s):   FPL-4714-1A   FPL-4723-1

Abstract: Electrical impedance spectra (EIS) were collected from southern pine (Pinus spp.) wood equilibrated to 12% moisture content. Cylindrical graphite electrodes were embedded in the wood so that they met nearly end-to-end along a line parallel to the grain, and the EIS properties were characterized as functions of electrode spacing and electrode contact pressure at frequencies between1◊10−1 and3◊105 Hz. The data show a narrow distribution of relaxation times, which can be fit using a Debye model or, even better, a model with a constant phase element (CPE) in parallel with a resistor. The relaxation time is sensitive to contact pressure applied to the electrodes but not electrode spacing. The width of the CPE distribution is sensitive to electrode spacing but not contact pressure. On first inspection, the data suggest a finite contact resistance between wood and electrode, but further examination reveals that the 'contact resistance' is an artifact caused by electrode fringe effects.

Keywords: Electrodes, electrochemical analysis, electric resistance, wood, electric properties, corrosion, anti-corrosives, testing, metals, accelerated life testing, moisture content, moisture, electric measurements, dielectric relaxation, impedance spectroscopy, Southern pine, electrical impedance spectroscopy, accelerated testing, circuit model, contact resistance

File size: 392 kb(s)

This publication is also viewable on Treesearch:  view
RITS Product ID: 1524
Current FPL Scientists associated with this product (listed alphabetically)
Rammer, Douglas R.
Research General Engineer
Zelinka, Samuel L.
Materials Research Engineer

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