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With the rapid development of wooden structure buildings in China, the demand for structural plywood enlarges significantly. Eucalyptus and poplar plantation is a very wide area of growth in china, therefore, there is practical significance to use eucalyptus and poplar plantation to produce wooden structural plywood. This study uses orthogonal test on pressing temperature, pressing time, pressing pressure, veneer glue spread - four factors influence the bond strength of structural plywood from Eucalyptus/poplar, and has obtained the superior technology. The results show that hot pressing temperature, pressing time, pressing pressure, veneer glue spread –four factors affect the bond strength of the structure plywood significantly, but the difference among the three veneer glue spread levels is not significantly. The better production technology is hot pressing temperature 135 °C, pressing time 24 min, pressing pressure 1.2 Mpa, veneer glue spread 320 g/m2.

An important way of conservation and protection of forest resources is wood preservative treatment. Currently, chemical preservatives are always used in the wood preservative treatment. Therefore, preservatives security has become an important environmental issue. This study focuses on national wood preservation, which workers are committed on. Many studies have been directed to look for new preservatives that are harmless to humans, animals and environment. Chinese herbal medicine as a wood preservative is selected for the environmental pollution problems of inorganic preservatives. In this paper, according to the application of traditional Chinese medicine, the nature of wood preservative and a preliminary study by the relevant trial, the theory of Chinese herbal medicine wood preservative is proposed. The results showed that Chinese herbal medicine can be used as wood preservatives. Finally, the paper puts forward the potential abilities of Chinese herbal medicine as wood preservatives.

Xanthoceras Sorbifolia Bunge crust was used as source material to make carbon by chemically impregnated by sodium hydroxide、carbonized at 220°C and activated under the protection of the nitrogen. Experiments were carried out as function of contact time, pH (4-10) and temperature (293,303 and 313K). Adsorption isotherms were modeled with the Langmuir and Freundlich isotherms. Adsorption isotherms of Basic Fuchsin on Xanthoceras Sorbifolia Bunge crust activated carbon are consistent with Langmuir equation. The Langmuir monolayer saturation capacities of BF adsorbed onto activated carbon were 286.545, 303.617 and 323.816 mg/g at 293,303, and 313 K, respectively.and adsorption kinetics were found to conform to the pseudo-second-order kinetics with good correlation.Using the equilibrium concentration contents obtained at different temperatures, various thermodynamic parameters,such as △G,△H and △S, have been calculated. The thermodynamics parameters of system indicated spontaneous and endothermic process.

Adsorption of cationic dye, methylene blue (MB) onto Xanthoceras Sorbifolia Bunge hull activated carbon (XSBHAC) developed by zinc chloride solution activation has been investigated. Exp eriments were carried out as function of contact time, pH (2-10) and temperature (293, 303, 313 and 323K). Adsorption isotherms were modeled with the Langmuir and Freundlich isotherms. The data fitte d well with the Langmuir isotherm. The Langmuir monolayer saturation capacities of MB adsorbed onto activated carbon were 501.32, 534.54, 588.30 and 593.28mg/g at 293, 303,313, and 323 K, respect ively. The kinetic models were also studied. The rates of adsorption were found to conform to the pseu do-second-order kinetics with good correlation. Using the equilibrium concentration contents obtained at different temperatures, various thermodynamic parameters, such as△G, △H and△S, have been calc ulated.The thermodynamics parameters of system indicated spontaneous and endothermic process.

Two-step for wood esterification with oxalic acid and cetyl alcohol is developed in this study. The esterified wood powder was investigated by Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The results show that ester groups substituted parts of the original alcoholic hydroxyl groups, and crystallization occurred during the modification. In addition, surface wettability, moisture adsorption and water absorption tests for wood specimen have showed that the modification improves the moisture and water resistance.