Papers by Author: Jing Hui Jiang

Paper TitlePage

Authors: Qiang Shi, Jing Hui Jiang
Abstract: This study describes experiments of testing the color stability of heat-treated okan sapwood samples. Heat-treatment was done at 160°C,180°C,200°C,220°C during 4 hours, under steam. series of experiments were carried out to investigate the color stability of heat-treated okan sapwood compared to untreated wood during 100 hours xenon light irradiation. Color measurements during accelerated weathering were made at intervals throughout the test period. The results are presented in △E* and L* a* b*coordinates according to the CIE(1976)L*a*b* parameters color system. Better photo-stability in terms of color changes was recorded for heat-treated wood compared to the untreated one. The properties of heat treated wood are involved in the heat-treated wood resistanceagainst xenon light under experimental conditions.
Authors: Qiang Shi, Fu Cheng Bao, Jian Xiong Lu, Jing Hui Jiang
Abstract: In this study the effect of high temperature on color change of okan wood was investigated. Wood specimens were subjected to heat treatment at 160°C, 180°C,200°C,220°Cfor 4 hours with the superheated steam as a heating medium and a shielding gas. Color changes were measured in the Minolta Croma-Meter CR-300 color system. The color parameters L*, a*, b* were determined by the CIEL*a*b* method on the surface of untreated and treated wood, and their variation with regard to the treatment (△L*,△a*,△b* ) were calculated. It was found that heat treatment resulted in a darkening of wood tissues, Color became dark with the temperature increases. The darkening accelerated when treatment temperature exceeded approximately 200°C. We found that heat treatment temperature were substantially important regarding the color responses. Strong correlations between total color difference and the treatment temperature were found. The effect of treatment temperature on color change in sapwood is more obvious than that in heartwood, the color of sapwood and heartwood tended to be more uniform when the temperature reaches more than 200°C.
Showing 1 to 2 of 2 Paper Titles