Moisture Sorption Isotherms of the Wood and Inner Bark of Ten Southern U.S. Hardwoods
Keywords:Wood moisture, moisture relationships, moisture models
AbstractThe adsorption isotherms of the woods and inner barks of ten hardwoods, measured at 25 C and atmospheric pressure, were essentially identical, but the desorption isotherms for the barks were consistently lower than those for the woods. Three fundamental constants were required to evaluate the isotherms in terms of the Dent (1977) model, a modification of the classical BET surface model, and of the Hailwood-Horrobin (1946) single-hydrate solution model. Two of these constants are identical for the two models, but the third is somewhat lower for the Dent model. Both models divide the sorbed water into two components, one strongly bonded and the other more weakly bonded to the wood or bark substrate. Also both models predict an identical parabolic relationship giving the ratio of the relative humidity to the moisture content as a function of relative humidity.
Brunauer, S., P. H. Emmett, and E. Teller. 1938. Adsorption of gases in multimolecular layers. J. Am. Chem. Soc. 60:309-319.nChoong, E. T., and F. G. Manwiller. 1976. Dimensional and relative hygroscopic properties of hardwoods from southern pine sites. Wood Sci. 9(1):39-43.nDent, R. W. 1977. A multilayer theory for gas sorption. Part I: Sorption of a single gas. Textile Res. J. 47(2):145-152.nHailwood, A. J., and S. Horrobin. 1946. Absorption of water by polymers: analysis in terms of a single model. Trans. Faraday Soc. 42B:84-92.nMartin, R. E. 1967. Interim equilibrium moisture content values of bark. For. Prod. J. 17(4):30-31.nOkoh, I. K. A. 1976. Moisture sorption and electrical resistivity of some woods and barks. Ph.D. Diss., Dept. of Wood Products Engin., SUNY College of Environmental Science and Forestry. Syracuse, N.Y.nSimpson, W. T. 1973. Predicting equilibrium moisture content of wood by mathematical models. Wood Fiber 5(1):41-49.nSkaar, C. 1972. Water in wood. Syracuse University Press. Syracuse, N.Y.nSpalt, H. A. 1958. The fundamentals of water vapor sorption by wood. For. Prod. J. 8(10):288-295.nStamm, A. J. 1964. Wood and cellulose science. Ronald Press, New York.nVenkateswaran, A. 1970. Sorption of aquaeous and non-aquaeous media by wood and cellulose. Chem. Rev. 70(6):619-637.nWood Handbook. 1955. U.S. Dep. Agr. For. Serv. Hdbk. No. 72. For. Prod. Lab. Madison, WI.nWood Handbook. 1974. U.S. Dep. Agr. For. Serv. Hdbk. No. 72. (Rev.). For. Prod. Lab. Madison, WI.n
The copyright of an article published in Wood and Fiber Science is transferred to the Society of Wood Science and Technology (for U. S. Government employees: to the extent transferable), effective if and when the article is accepted for publication. This transfer grants the Society of Wood Science and Technology permission to republish all or any part of the article in any form, e.g., reprints for sale, microfiche, proceedings, etc. However, the authors reserve the following as set forth in the Copyright Law:
1. All proprietary rights other than copyright, such as patent rights.
2. The right to grant or refuse permission to third parties to republish all or part of the article or translations thereof. In the case of whole articles, such third parties must obtain Society of Wood Science and Technology written permission as well. However, the Society may grant rights with respect to Journal issues as a whole.
3. The right to use all or part of this article in future works of their own, such as lectures, press releases, reviews, text books, or reprint books.