A comparative study was conducted on liquid penetration of the freeze-drying and air-drying sapwood and heartwood lumber of plantation Chinese fir (Cunninghamia lanceolata). The maximum amount of dyeing solution upt...A comparative study was conducted on liquid penetration of the freeze-drying and air-drying sapwood and heartwood lumber of plantation Chinese fir (Cunninghamia lanceolata). The maximum amount of dyeing solution uptake by the capillary rise method was used to evaluate the liquid penetration properties of the treated wood. The pit aspiration ratio was determined by semithin section method. Changes in wood microstructure were investigated using scanning electron microscopy. The results showed that compared with air drying, the freeze drying had a significant effect on liquid penetration of sapwood and heartwood of Chinese fir. The liquid penetration of sapwood is significantly higher than that of the heartwood for both drying treatments. Low pit aspiration ratio and cracks of pits membrane of some bordered pits are the main reasons for increasing liquid penetration after freeze drying treatment.展开更多
该文主要为研究液体性质以及喷嘴结构对气泡喷嘴雾化特性的影响。实验用浆体包括水和6种高黏度流体。采用相位多普勒粒子分析仪对多种流体进行雾化实验研究。对喷嘴几何结构和操作参数对雾化的影响进行了讨论。雾化液滴沿径向的索特平...该文主要为研究液体性质以及喷嘴结构对气泡喷嘴雾化特性的影响。实验用浆体包括水和6种高黏度流体。采用相位多普勒粒子分析仪对多种流体进行雾化实验研究。对喷嘴几何结构和操作参数对雾化的影响进行了讨论。雾化液滴沿径向的索特平均直径(Sauter mean diameter,SMD)最大值在120μm以内。提高气液比能有效降低雾化液滴SMD。喷嘴出口直径和注气孔直径对水的雾化液滴SMD的影响显著,而改变注气角度和混合室长度对水的雾化液滴SMD影响不大。混合室长度增加后,非牛顿流体的雾化质量有一定下降。黄原胶添加量的提高对雾化液滴SMD有很大影响。在雾化介质为水的情况下,液滴SMD变化范围为60~95μm;雾化高黏度流体时SMD范围为60~120μm。展开更多
基金This paper was supported by the National Natural Science Foundation of China (No. 30271053)
文摘A comparative study was conducted on liquid penetration of the freeze-drying and air-drying sapwood and heartwood lumber of plantation Chinese fir (Cunninghamia lanceolata). The maximum amount of dyeing solution uptake by the capillary rise method was used to evaluate the liquid penetration properties of the treated wood. The pit aspiration ratio was determined by semithin section method. Changes in wood microstructure were investigated using scanning electron microscopy. The results showed that compared with air drying, the freeze drying had a significant effect on liquid penetration of sapwood and heartwood of Chinese fir. The liquid penetration of sapwood is significantly higher than that of the heartwood for both drying treatments. Low pit aspiration ratio and cracks of pits membrane of some bordered pits are the main reasons for increasing liquid penetration after freeze drying treatment.
文摘该文主要为研究液体性质以及喷嘴结构对气泡喷嘴雾化特性的影响。实验用浆体包括水和6种高黏度流体。采用相位多普勒粒子分析仪对多种流体进行雾化实验研究。对喷嘴几何结构和操作参数对雾化的影响进行了讨论。雾化液滴沿径向的索特平均直径(Sauter mean diameter,SMD)最大值在120μm以内。提高气液比能有效降低雾化液滴SMD。喷嘴出口直径和注气孔直径对水的雾化液滴SMD的影响显著,而改变注气角度和混合室长度对水的雾化液滴SMD影响不大。混合室长度增加后,非牛顿流体的雾化质量有一定下降。黄原胶添加量的提高对雾化液滴SMD有很大影响。在雾化介质为水的情况下,液滴SMD变化范围为60~95μm;雾化高黏度流体时SMD范围为60~120μm。