Variation of measured cross-sectional cell dimensions and calculated water vapor permeability across a single growth ring of spruce wood

Abstract

A statistical study of the cell dimensions in a growth ring of spruce along the radial and tangential directions is performed. The data are used to study the variation of the cell vapor permeability in the growth ring. Studying cell rows within one growth ring, the frequency distributions of the cell wall thickness in the radial direction and of the lumen dimension in the tangential direction are found to be both unimodal. In contrast, the frequency distributions of these dimensions in the other directions are bimodal, where the different modes can be attributed to earlywood and latewood. Analysis of the bimodal distributions results in the determination of threshold values of cell wall thickness and the lumen dimension for earlywood and latewood tracheids. The cell dimensions are used to predict cell porosity and water vapor permeability distribution within a growth ring. The bimodal frequency distributions of the tangential cell wall thickness and the radial lumen dimension provide an explanation for the observed bimodal frequency distribution of the cell water vapor permeability both in radial and in tangential directions. Contrary to measured macroscopic vapor permeability results, the tracheid geometry results in lower cell vapor permeability in radial than in tangential direction. This confirms that rays play an important role in the vapor permeability of D. Derome (&) Fluids and porous materials, EMPA, Ü berlandstrasse 129,

Effects of heat-treatment on permeability of untreated and nanosilver-impregnated native hardwoods

“…Understanding wood permeability is of vital importance as it has great impact on its utilization in different industries (such as: wood preservation, wood drying, pulp and paper) (Chen et al 1998, Dermoe et al 2012. Gas permeability values in solid woods can be measured with 0.001 second precision , Taghiyari and Sarvari 2010, Taghiyari 2011a) and therefore can be helpful in scientific and industrial purposes.…”

Distribution of structure and lignin within growth rings of Norway spruce

“…However, a more complete description of cell geometry within single growth rings can scarcely be found in the literature. Derome et al (2011b) studied relations between cell geometry and vapor permeability across a growth ring. In this study, ESEM images of the radial/ tangential surface containing one complete growth ring were used to manually measure the lumen dimensions and cell wall thicknesses in both the radial and the tangential directions.…”

Effects of nanosilver-impregnation and alfalfa-intercropping on fluid transfer in downy black poplar wood

“…Many techniques have been brought up to measure permeability in solid woods and wood-composite materials (Dermoe et al 2012). In the present study, longitudinal gas permeability measurement apparatus was invented by the author based on the microstructure porosity of wood (Taghiyari 2012a) (Figure 1).…”