Fig. 3From: Relationship between pore structure and gas permeability in poplar (Populus deltoides CL.’55/65’) tension woodAir (a) and nitrogen (b) permeation flux curves for poplar tension wood with a longitudinal length of 6 mm. Three replicates were carried out in each case and marked as − 1, − 2, and − 3. TW6: tension wood with longitudinal length of 6 mmBack to article page