The permeability to water of spruce heartwood has been measured by applying a known osmotic pressure difference across specimens in which the cell walls were water swollen and most of the void space was filled with paraffin wax. To ensure that solute molecules should not penetrate the cell wall aqu
Permeability to water of the wood cell wall and its variation with temperature
β Scribed by M. Anne Palin; J. A. Petty
- Publisher
- Springer
- Year
- 1983
- Tongue
- English
- Weight
- 410 KB
- Volume
- 17
- Category
- Article
- ISSN
- 0043-7719
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β¦ Synopsis
The permeability to water of the cell wall has been measured by applying a known osmotic pressure generated by PEG 6000 across wood samples containing water-swollen cell walls. In pine the void space was filled with silicone resin with the wood at near fibre saturation point. Permeability kβ’ 1021 as defined by the Darcy equation was 37.9m 2 for longitudinal flow and 0.96 m 2 for tangential flow. Tangential permeability was also measured using water-saturated samples of spruce and lime, and allowance was made for the very high permeability of the water-filled cell cavities. The results were in satisfactory agreement with values obtained previously using wood filled with wax or resin. The variation of tangential permeability with temperature was measured over the range 10-55 ~ for pine and lime. The activation energy for flow through the cell wall was 6.8 kcal/mole for pine and 5.3 kcal/mole for lime. These values are much higher than the activation energy for viscous flow of water, presumably owing to hydrogen bonding of the water to the cell wall material.
π SIMILAR VOLUMES
Using a stopped-flow device, the osmotic water permeability of human red cells to D,O and H,O was studied as a function of temperature and under the influence of the sulfhydryl reagent paracholoromercuribenzene sulfonic acid (PCMBS), an inhibitor of water transport. The ratio, permeability (D,O)/ pe