Dielectric Properties of Wood and Wood-Based Materials

Provided here is a comprehensive treatise on all aspects of dielectric properties of wood and wood products. The topics covered include: Interaction between electromagnetic field and wood. - Wood composition and dielectric properties of its components. - Measurement of dielectric parameters of wood.- Dielectric properties of oven-dry wood. - Dielectric properties of moist wood. - Effect of different kinds of treatment on dielectric properties of wood. - Dielectric properties of bark. - Dielectric properties of wood-based materials. - Recommendations for determination of dielectric parameters of wood based materials and for their use in calculations. Several appendices comprise reference data onthe dielectric characteristics of wood and wood-based materials in the wide range of frequencies, temperatures, and moisture content.

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1 Interaction between the Electromagnetic Field and Wood. Main Features of Dielectric Properties of Wood.- 1.1 Polarization of Wood.- 1.2 Dielectric Parameters of Wood.- 1.3 Some Principal Formulas Reflecting Interactions Between an Electromagnetic Field and a Material.- 2 Wood Composition and Dielectric Properties of Its Components..- 2.1 Physical Model of Wood as a Multicomponent Dielectric.- 2.2 Dielectric Parameters of the Cell Wall Substance and Its Elements.- 2.3 Dielectric Characteristics of Air, Free and Bound Water, and Ice.- 3 Measurement of the Dielectric Properties of Wood.- 3.1 Measurement of the Dielectric Constant and Loss Tangent at Low Frequencies.- 3.2 Measurements of the Dielectric Constant and Loss Tangent at High Frequencies.- 3.3 Measurement of the Dielectric Constant and Loss Tangent at Super High Frequencies.- 3.4 Preparation of Samples.- 4 Dielectric Properties of Oven-Dry Wood.- 4.1 Influence of Anisotropy, Density, and Frequency on the Dielectric Constant, Loss Tangent, and Loss Factor.- 4.2 Influence of Temperature on Dielectric Properties.- 5 Dielectric Properties of Moist Wood.- 5.1 The Dielectric Constant of Moist Wood.- 5.2 The Dielectric Loss Tangent of Moist Wood.- 5.3 The Dielectric Loss Factor of Moist Wood.- 5.4 Mechanism of the Influence of Moisture Content on the Dielectric Properties of Wood.- 6 Effect of Different Kinds of Treatment on the Dielectric Properties of Wood.- 6.1 Dielectric Properties of Compressed Wood.- 6.2 Dielectric Characteristics of Modified Wood.- 6.2.1 Wood Treated with Ammonia.- 6.2.2 Dielectric Properties of Wood Impregnated with Various Substances.- 6.3 Influence of Gamma-Radiation on the Dielectric Properties of Wood.- 7 Dielectric Properties of Bark.- 8 Dielectric Properties of Wood-Based Materials.- 8.1 Cellulose, Paper and Board.- 8.1.1 Influence of Density Value, Moisture Content, and Temperature on the Dielectric Properties of the Material.- 8.1.2 Influence of the Structure of Paper and Board on Their Dielectric Properties.- 8.1.3 Influence of Organic and Mineral Inclusions on the Dielectric Properties of Cellulose-Based Materials.- 8.2 Fiberboards.- 8.3 Particleboards.- 8.4 Materials Containing Wood, Cellulose, Paper (as a Filler), and Cellulose Derivatives.- 9 Recommendations for the Determination of the Dielectric Parameters of Wood and Wood-Based Materials and for Their Use in Calculations.- 9.1 Dielectric Parameters and Density of Oven-Dry Wood.- 9.2 Averaging the Dielectric Parameters Values.- 9.3 Choice of Frequency on Microwave Treatment of Wood.- Appendices.- References.