<正>根据约翰?F?肖非稳态传热传质理论，建立了马尾松锯材在热压干燥过程中的传热数学模型。将马尾松锯材在干、湿球温度分别为100，99.5℃，即相对湿度约为100%的条件下汽蒸处理3h，然后在温度为180℃，压力为0.2MPa、呼吸间隔为60s（每次呼吸约1s）的工艺条件下进行热压干燥验证试验。结果表明，除少数几个值外，其余各点的实测温度与计算温度之间偏差均小于5%。该模型较好地反映了在热压干燥过程中马尾松锯材内的温度变化。

The reaction of pine seedlings to infection of pine wood nematode(Bursaphelenchus xylophilus) was similar to that of in vitro seedling twigs. Both showed the sign of wilting and tissue brown spot, the reaction of 2 or 4-month seedlings to PWN appeared clearer and faster than that of 1-year-old pine seedlings and in vitro seedling twigs. After being infected by PWN,the needle of 1-year-old pine seedlings with the lignified stem began to change to be bronzing or brown and wilted, which appeared at the phyllopodium and expanded to leaf apex, then the needles withered and died. The sign showed that the disease had reached an advanced stage,where the host was almost dead and water loss in the stem and cell necrosis had widely occurred. The experiment showed the same results in in vitro seedlings. The necrosis was a common phenomenon caused by PWN and directly related to its moving, spreading, distribution and amount. The visible brown spot at cortex and marrow appeared after nematode occurrence, and the degree of internal pathological changes was linear to nematode amount.