Conservation of archival and library materials-Mass strengthening of deteriorated paper-

1.纸张降解性的评价：为了找出合适的方法来评价纸张的降解率，我们对一些自然老化的书刊纸进行了感官判断、力学测量和裂解气相色谱分析。声发射和“滚动测试”似乎是有效的。我们认为，它们值得进一步关注，因为它们比传统的双重折叠测试破坏性小得多。通过裂解气相色谱，以左旋葡聚糖和左旋糖苷酮的相对峰面积为指标，可以对纸张的降解率进行评价。纸张增强方法：(1)大量研究了使用纤维素衍生物对纸张进行增强。水溶性纤维素衍生物首先溶解在最少量的水中，然后分散在乙醇中。通过喷雾将增强剂涂抹在纸张表面，从而使涂布容易且均匀。在乙醇中使用乳化液有助于缩短干燥时间，防止纸张因潮湿而变形。通过力学性能测试对增强剂的效果进行了评价。这种方法最适合于未处于高级降解阶段的纸张。(2)处于高级降解阶段的纸张需要更激进的措施，如纸张裂解。利用人工老化程度不同的纸张样品，研究了该方法与纸张降解率的兼容性。

1. Evaluation of the degradation ofpaper:In order to find out appropriate methods to the evaluation of the rate of degradation of paper, we carried out sensory judgment, mechanical measurement and pyrolysis - gas chromatography on a number of natural aged book papers. The acoustic emission and the "rolling test" appeared to be effective. We believe that they deserve further attention as they are much less destructive than a conventional double fold test. Through pyrolysis - gas chromatography, by using the relative peak areas of levoglucosan and levoglucosenone as an index, an evaluation of the rate of degradation of paper seems possible.2. Paper strengthening methods:(1) Strengthening of paper using cellulose derivatives has been largely investigated. Water-soluble cellulose derivatives are first dissolved in the minimum amount of water and dispersed in ethanol. The strengthening agents are applied to the paper surface by spraying, and thus enabled an easy and even application. The use of emulsion in ethanol contributes to shorten the drying time and to prevent deformation of paper due to moisture. The effect of strengthening agents has been evaluated through mechanical measurement. This method is most appropriate to paper which is not in an advanced stage of degradation.(2) Paper in an advanced stage of degradation requires a more radical measure such as paper-splitting. The compatibility of this method in connection with the rate of degradation of paper has been studied using paper samples which had been aged artificially to different degrees.