Real-Time Measurement of the Viscoelasticity of Green Juvenile Wood of Japanese Cedar at High Temperature
Keywords:
High temperature, juvenile wood, real-time measurement, vibration test, viscoelasticityAbstract
Changes in the viscoelasticity of green juvenile and mature wood during high-temperature drying were measured in real time. For each measurement, a 180-mm-long specimen of Japanese cedar (Cryptomeria japonica), its supporting system, a magnetic driver, and a deflection sensor were placed in an electric oven and a free-free flexural vibration test was performed. The temperature was fixed at 120°C. The resonance frequency decreased and the loss tangent increased during heating of the juvenile vs mature wood. These tendencies apparently occurred because the initial moisture content of the juvenile wood was higher than mature wood and because the juvenile wood had the larger number of intercellular layers.References
Chiba Y. (1999) Utilization of thinnings. Pages 58-59 in the Committee of The Encyclopedia of Wood Industry, ed. The encyclopedia of wood industry. Wood Technological Association of Japan, Tokyo, Japan.nFranklin GL. (1945) Preparation of thin section of synthetic resins and wood-resin composites, and a new maceration method for wood. Nature 3924:51.nFukazawa K. (1967) The variation of wood quality within a tree of Cryptomeria japonica D. Don.—Characteristics of juvenile and adult wood resulting from various growth condition and genetic factors. Research Bulletin of the Faculty of Agriculture Gifu University 25:47-127.nFuruta Y, Nakajima M, Nakatani T, Kojiro K, Ishimaru Y. (2008) Effects of the lignin on the thermal-softening properties of the water-swollen wood. J Soc Mat Sci Jpn 57:344-349.nGoring DAI. (1963) Thermal softening of lignin, hemicellulose and cellulose. Pulp Paper Mag Can 64:T517-T527.nIdo H, Nagao H, Kato H, Yoshida N. (2007) Abstract of the 57th Annual Meeting of the Japan Wood Research Society, Hiroshima, Japan. PD017.nIizuka K, Okazaki K, Eizawa J, Saito Y, Ishiguri F, Mustafa AKA, Yokota S, Yoshizawa N. (2007) Wood structure and static bending properties in juvenile wood of 26-year-old sugi from seedlings. Wood Ind 62:22-27.nJozsa LA, Middleton GR. (1994) A discussion on wood quality attributes and their practical implications. Forintek Canada Corp Special Publication SP-34.nJozsa LA, Munro BD, Gordon JR. (1998) Basic wood properties of second-growth western hemlock. Forintek Canada Corp Special Publication SP-38.nKubojima Y, Kobayashi I, Tonosaki M, Suzuki Y. (2009) Equilibrium moisture content of Japanese cedar (Cryptomeria japonica) green wood for columns in a high-temperature water vapor environment. J Jpn Wood Res Soc 55:279-284.nKubojima Y, Suzuki Y, Tonosaki M. (2002) Real-time measurement of vibrational properties of green wood at high temperatures. Wood Fiber Sci 34:643-650.nKubojima Y, Suzuki Y, Tonosaki M. (2004) Real-time vibration testing method of wood in superheated water vapor. Bull For For Prod Res Inst 393:335-339.nKubojima Y, Suzuki Y, Tonosaki M. (2005) Vibrational properties of green wood in high temperature water vapor. Holzforschung 59:446-450.nKubojima Y, Suzuki Y, Tonosaki M, Ishikawa A. (2003) Moisture content of green wood in high temperature water vapor. Holzforschung 57:634-638.nKubojima Y, Wada M, Suzuki Y, Tonosaki M. (2001) Real-time measurement of vibrational properties and fine structural properties of wood at high temperature. Wood Sci Technol 35:503-515.nNara N, Chiba M, Oyama Y. (1977) Prevention of defect-occurrence in todomatsu squares during kiln-drying. J Hokkaido For Prod Res Inst 309:1-4.nOhsaki H, Kubojima Y, Tonosaki M, Ohta M. (2007) Changes in vibrational properties of wetwood of Japanese fir (Abies Sachalinensis Mast) with time during drying. Wood Fiber Sci 39:232-240.nOhta S. (1972) Studies on mechanical properties of juvenile wood, especially of sugi-wood and hinoki-wood. Bulletin Kyusyu Univ For 45:1-80.nOhta S, Watanabe H, Matsumoto T, Tsutsumi J. (1968a) Studies on mechanical properties of juvenile wood. I. Fibril angle and dynamic modulus of elasticity of juvenile wood in stem of sugi-trees. Reports Kyusyu Univ For 22:105-116.nOhta S, Watanabe H, Matsumoto T, Tsutsumi J. (1968b) Studies on mechanical properties of juvenile wood. II. Variation of fundamental structural factors and mechanical properties of hinoki trees (Camaecyparis obtusa Sieb. et Zucc.). J JpnWood Res Soc 14:261-268.nPanshin AJ, De Zeeuw C, Brown HP. (1964) Textbook of wood technology. Volume I—Structure, identification, uses, and properties of the commercial woods of the United States Second Edition. McGraw-Hill Book Company, New York, NY.nSaiki H, Miyazaki Y, Wakashima T. (1958) Electronmicroscopic investigation on the cell wall structure of wood. Bull Gov For Exper Sta 104:1-115.nShiokura T. (1982) Extent and differentiation of the juvenile wood zone in coniferous tree trunks. J Jpn Wood Res Soc 28:85-90.nShiokura T, Watanabe H. (1972) Fundamental studies on wood quality of larch tree (Larix leptolepis Gord.). (Part 3) Variation of tracheid length and fibril angle within a tree trunk. J Agric Sci Tokyo 17:81-86 (Nogyo Daigaku).nShiokura T, Watanabe H. (1973) Studies on juvenile wood (Part 5). The influence exerted by the early growth hastening on the variation in average tracheid length in the radial direction across tree trunks of sugi (Crypotomeria japonca D. Don). J Agric Sci Tokyo 18:139-144 (Nogyo Daigaku).nTakamura N. (1968) Studies on hot pressing and drying process in the production of fibreboard. III. Softening of fibre components in hot pressing of fibre mat. J Jpn Wood Res Soc 4:75-79.nTansho T, Noda Y, Matusmoto K, Maeda N. (2007) Abstract of the 57th Annual Meeting of the Japan Wood Research Society, Hiroshima, Japan. D10-0930.nWatanabe H, Tsutsumi J, Kojima K. (1963) Studies on juvenile wood. I. Experiments on stems of sugi trees (Cryptomeria japonica D. Don). J Jpn Wood Res Soc 9:225-230.nWatanabe H, Tsutsumi J, Matsumoto T, Ohta S. (1964) Studies on juvenile wood. II. On distribution of specific compressive strength and specific modulus of elasticity in stem of sugi trees (Cryptomeria japonica D. Don). J Jpn Wood Res Soc 10:125-130.n
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