WOOD RESEARCH Volume 69, Number 2, 2024
CUIXIANG LU, XINGXING LIANG, YUAN LIU, DONGQIANG GUO, JIANBO CHEN, HUICHUAN JIANG, and TAO JIANG

LIQUID PERMEABILITY OF EUCALYPTUS UROPHYLLA WOOD TREATED WITH DIFFERENT DRYING METHODS

In this study, the influence of three different drying methods on the liquid permeability of sapwood and heartwood of Eucalyptus urophylla was investigated. The liquid permeability of the dried wood was assessed by measuring the maximum amount of dyeing solution uptake using the capillary rise method. Subsequently, the microscopic structure of the dried wood was examined by scanning electron microscopy (SEM). The results indicated that the liquid permeability of sapwood dried by microwave vacuum drying (MVD) and conventional kiln drying (KD) was significantly more effective than that of air drying (AD) treated wood. However, there is no significant difference in the effect of MVD and KD on the liquid permeability of sapwood. The liquid permeability of heartwood treated with MVD is significantly better than that treated with KD and AD, and the effect in the effects of AD and KD on the heartwood is not significant. The increased permeability of Eucalyptus urophylla wood can be attributed to the occurrence of macro-cracking or micro-structural damage in the test specimens, resulting from the dislodgement of perforated plates within the wood cells, the rupture of the intercellular layer between vessel and axial parenchyma cells, as well as the rupture of the pit membrane in cross-field pits due to microwave vacuum drying and conventional kiln drying

WOOD RESEARCH Volume 67, Number 3, 2022
CUIXIANG LU, YUAN LIU, HUICHUAN JIANG, and QUANJI LU

Impact of heat treatment on the surface color and glossiness of young eucalyptus wood

The study analyzed the impact of heat treatment conditions (temperature and duration) on the surface color and glossiness of young eucalyptus wood. The young eucalyptus wood samples were treated at different treatment temperatures (165°C, 185°C, 205°C) and duration (2 h, 3 h, 4 h). The color of the young eucalyptus wood was determined using CIE L*a*b* system and the gloss was measured with glossmeter at 20°, 60°, and 85° incident angle before and after the heat treatment. The total color difference (E* ), lightness (L*), red-green index (a*), and yellow-blue index (b*), were investigated at different treatment conditions. The values of L* and b* decrease continuously with the increasing temperature and duration. The results of analysis of variance (two-way ANOVA) indicate that the heat treatment temperature has a significant effect on the colorimetric properties of the heat-treated young eucalyptus wood. The gloss decreased after the heat treatment for both perpendicular and parallel directions. ANOVA analysis showed that the treatment temperature duration have a significant effect on the parallel glossiness of 85°(p＜0.05). These are probably due to differences in surface roughness between untreated and heat-treated wood. To achieve the desired color like teak wood, the preferred temperature is no more than 185°C.

WOOD RESEARCH Volume 66, Number 4, 2021
Li Quan, Ning Ji, Zhanguang Wang, CUIXIANG LU, and Lin Hui

Four solvent extraction of Cinnamomum camphora xylem and analysis of the anti-fungal activity of the extractives

Four solvents including distilled water, acetone, ethyl acetate and petroleum ether were used to extract xylem of C. camphora. The differences in chemical compounds of xylem of C. camphora were analyzed by gas chromatography/mass spectrometry (GC/MS) and the anti-fungal activity of C. camphora extractives on Coriolus versicolor (CV), Trametes versicolor (TV), Poria vaporaria (PP) and Gloeophyllum trabeum (GT) were tested. The result showed that the chemical composition and relative content of the four different solvent extracts were different. A large number of chemical compounds in the C. camphora extractives had a variety of biological activity and certain application value. The growth inhibitory rates of ethyl acetate extracts of C. camphora on PP, CV, TV and GT were 52.24%, 52.51%, 43.26%, and 54.63%, respectively. According to the concentration for 50% of maximal effect, the inhibitory order on test fungus were GT > PP > CV > TV.