<正>对日本落叶松不同树龄纸浆物理性能进行了研究，并对KP浆和AS—AO浆的未漂浆和漂白浆的强度进行了比较分析。结果表明：树龄对日本落叶松KP浆和。AS-AO浆的物理性能有一定的影响。日本落叶松KP未漂浆的物理性能接近针叶木硫酸盐未漂浆国家标准B等，漂白浆的强度达到了漂白硫酸盐针叶木浆的国家标准A等。日本落叶松AS-AQ浆（包括未漂浆和漂白浆）的物理性能达到了亚硫酸盐针叶木浆的国家标准A等；浆的抗张指数、裂断长、耐折度和耐破指数都要好于KP浆，但是在撕裂指数上KP浆要优于ASAQ浆。

The membrane fouling and its reversibility during ultrafiltration of xylan extractives were invesiigated, and the method to clean the fouled membrane was examined. It was found that lower transmembrane pressure and higher feeding velocity were favorable to alleviate the membrane fouling, that 4% NaOH solution could efficiently recover the solvent flux through the membrane, but backwash could only regain the part of the solvent flux.