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The fossils of Hamipterus tianshanensis (Wang et al. in Curr Biol 24:1323–1330, 2014) and their eggs have important scientific significance because they can provide unique information about the reproduction, development, and evolution of pterosaurs. The fossils and the rock surrounding them have, however, been weathered, which including powdering and flaking, since they were relocated from Xinjiang to Beijing. The high content of soluble salts is a significant factor in fossil deterioration because the dissolution–recrystallization process can generate tremendous pressure and lead to decreased mechanical strength. This study evaluated the electrokinetic desalination performance for the fossils, and two types of poultices employed including paper pulp from Bioline® and CKS121 (cellulose: kaolin: sand = 1:2:1, w/w). Mercury intrusion porosimetry (MIP), scanning electron microscopy (SEM), ion chromatography (IC), and other methods were applied to evaluate the desalination effect. The surface salt content reduction by applied direct current (DC) was about 70%, and the inner salt content reduction was about 80%. The experimental results suggest that the electrokinetic method is a promising way to desalinate fossils. Nonetheless, cracks appeared in the surrounding rock crack after electrokinetic desalination, which can be explained by the montmorillonite swelling-induced stresses. Pre-consolidation, especially for electro-chemical method may solve the cracking problem for the clay-rich sandstone desalination. [ABSTRACT FROM AUTHOR]

As the crossroads of prehistoric cultures, the Beijing region is an important area for studying the exchange of prehistoric culture and the spread of millet agriculture. Although millet remains have been found in the Donghulin site during the Early Neolithic Age, there is little millet remains during the Middle and Late Neolithic Age, so there is a gap of approximately 2,000 years since the time of the Donghulin site. The Shangzhai site is located in the Pinggu Basin in eastern Beijing, and it has a large time span with sequential strata; however, there are few large animals and plant remains found at this site, thus the subsistence strategy of ancient people remains unclear. In this study, the absorbed lipids of pottery sherds unearthed in the Neolithic cultural layer of the Shangzhai site were extracted and analysed. The results show that these potteries were used to process millet, the meat of terrestrial non-ruminants and wild ruminants, and dairy of wild ruminants, providing new insights for the subsistence strategy and the development of millet agriculture in the Middle and Late Neolithic Age of Beijing. In addition, the food processing in pottery may be an internal heating method, such as stone boiling. [ABSTRACT FROM AUTHOR]