Abstract
A model has been developed aiming at the description of the effect of thermal modification on the electrical conductivity of wood. The intention was to calculate the moisture content (MC) of thermally modified timber (TMT) through the parameters electrical resistance R, wood temperature T, and CIE L*a*b* color data, which are known to correlate well with the intensity of a heat treatment. Samples of Norway spruce (Picea abies Karst.) and beech (Fagus sylvatica L.) samples were thermally modified in laboratory scale at 11 different heat treatment intensities and the resistance characteristics of the samples were determined. Within the hygroscopic range, a linear relationship between the resistance characteristics and the mass loss (ML) through the heat treatment was established. Based on this, a model was developed to calculate MC from R, T, and ML. To validate this model, color values of 15 different TMTs from industrial production were determined for estimation of their ML and fed into the model. MC of the 15 arbitrarily heat-treated TMTs was calculated with an accuracy of ±3.5% within the hygroscopic range. The material-specific resistance characteristics based on experimental data led to an accuracy of ±2.5%.
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©2014 by Walter de Gruyter Berlin Boston
Artikel in diesem Heft
- Masthead
- Masthead
- Review
- Mode of action of brown rot decay resistance in modified wood: a review
- Original Articles
- Photoyellowing of chemically modified chemithermomechanical pulps (CTMP) from Eucalyptus globulus under various atmospheres
- Selective purification of bleached spruce TMP process water by induced air flotation (IAF)
- Evaluation of the effects of compression combined with heat treatment by nanoindentation (NI) of poplar cell walls
- Measured temperature and moisture profiles during thermal modification of beech (Fagus sylvatica L.) and spruce (Picea abies L. Karst.) wood
- Modeling the influence of thermal modification on the electrical conductivity of wood
- Spruce fiber properties after high-temperature thermomechanical pulping (HT-TMP)
- Efficiency of visual strength grading of timber with respect to origin, species, cross section, and grading rules: a critical evaluation of the common standards
- Synthesis of alcohol-soluble phenol-formaldehyde resins from pyrolysis oil of Cunninghamia lanceolata wood and properties of molding plates made of resin-impregnated materials
- Enzymatic strategies to improve removal of hexenuronic acids and lignin from cellulosic fibers
- Phylogenetic analysis of major molds inhabiting woods. Part 4. Genus Alternaria
- Short Notes
- Comparison of hydrogenolysis with thioacidolysis for lignin structural analysis
- Detection of complex vascular system in bamboo node by X-ray μCT imaging technique
- Obituary
- Professor Gösta Brunow (1936–2013)
- Meetings
- Meetings
Artikel in diesem Heft
- Masthead
- Masthead
- Review
- Mode of action of brown rot decay resistance in modified wood: a review
- Original Articles
- Photoyellowing of chemically modified chemithermomechanical pulps (CTMP) from Eucalyptus globulus under various atmospheres
- Selective purification of bleached spruce TMP process water by induced air flotation (IAF)
- Evaluation of the effects of compression combined with heat treatment by nanoindentation (NI) of poplar cell walls
- Measured temperature and moisture profiles during thermal modification of beech (Fagus sylvatica L.) and spruce (Picea abies L. Karst.) wood
- Modeling the influence of thermal modification on the electrical conductivity of wood
- Spruce fiber properties after high-temperature thermomechanical pulping (HT-TMP)
- Efficiency of visual strength grading of timber with respect to origin, species, cross section, and grading rules: a critical evaluation of the common standards
- Synthesis of alcohol-soluble phenol-formaldehyde resins from pyrolysis oil of Cunninghamia lanceolata wood and properties of molding plates made of resin-impregnated materials
- Enzymatic strategies to improve removal of hexenuronic acids and lignin from cellulosic fibers
- Phylogenetic analysis of major molds inhabiting woods. Part 4. Genus Alternaria
- Short Notes
- Comparison of hydrogenolysis with thioacidolysis for lignin structural analysis
- Detection of complex vascular system in bamboo node by X-ray μCT imaging technique
- Obituary
- Professor Gösta Brunow (1936–2013)
- Meetings
- Meetings