岩石材料工程性能的研究——石质文物保护科技的基础性研究方向

从既有岩石材料构筑物的研究、保护和利用出发,提出了岩石材料工程性能研究是石质文物保护科技保护的基础性研究方向,在总结了岩石力学、地球化学、地球物理学、环境地质学、矿物学五个相关领域的研究现状后指出目前存在的三大基础性问题。在此基础上提出了岩石材料工程性能研究的基本框架和首要问题,并对首要问题内的基本研究内容进行了较为详细的论述。     

Prehistoric exchange and interaction in southeastern southern africa: Marine shells and ostrich eggshell

The spatiotemporal distribution of seashells and ostrich eggshell in the Later Stone Age of southeastern southern Africa is used to infer several areas of social interaction. The inferred patterns are supported by comparisons with preferences for lithic raw materials and the distribution of bifacial stone arrows. Plusiers zones de l'interaction sociale sont déduites des distributions chronologiques et spatiales de la coquillage et de la coquille de'autruche de l'Age de la Pierre Récent au sud- est de l'Afrique australe. Ces distributions sont soutenues des préférences pour des matières premières lithiques et de la distribution des flèches bifaciales de la pierre. Provincial names and boundaries are as given on May 1, 1994     

From stone to metal: New perspectives on the later prehistory of West Africa

Earlier views saw West Africa as culturally stagnant through much of the Holocene until stimulus or intervention from north of the Sahara transformed Iron Age societies. Evidence accumulating over the past 15 years suggests that stone-using societies from 10,000 to 3000 B.P. were far more diverse than previously thought. Against an increasingly detailed record of Holocene climate change, the complexity of local adaptation and change is becoming better understood. Although a strong case currently exists for the introduction of copper and iron to West Africa from the north in the mid-first millennium B.C., the subsequent development of metallurgy was strongly innovative in different parts of the subcontinent. Soon after the advent of metals, a dramatic increase in archaeological evidence for social stratification and hierarchical political structures indicates the emergence of societies markedly more complex than anything currently documented in the Late Stone Age. The best-documented examples come from the Middle Niger region and the Nigerian forest. In these areas, earlier diffusionist models in which complexity originated outside West Africa have yielded to evidence that indigenous processes were instrumental in this transformation. Trade, ideology, climate shifts, and indirect influences from North Africa, including the introduction of the domesticated horse to the Sahelian grasslands, are identified as factors essential to an understanding of these processes.     

The Middle Stone Age of East Africa and the beginnings of regional identity

The history of research into the Middle Stone Age of East Africa and the present state of knowledge of this time period is examined for the region as a whole, with special reference to paleoenvironments. The known MSA sites and occurrences are discussed region by region and attempts are made to fit them into a more precise chronological framework and to assess their cultural affinities. The conclusion is reached that the Middle Stone Age lasted for some 150,000 years but considerably more systematic and in-depth research is needed into this time period, which is now perceived as of great significance since it appears to span the time of the evolution of anatomically Modern humans in the continent, perhaps in East Africa.     

The colour of the facades in Siena’s historical centre: I. Glazings (calcium oxalate films s.s.) and other finishes on the stone materials of the Cathedral’s main facade

This paper focuses on the long-debated topic of the so-called calcium oxalate films: their origin and meaning but also their age and original appearance. The restoration of the main facade of the Siena Cathedral provided a unique opportunity to this end, thanks to the possibility of an extensive and detailed sampling and (as rarely happens) a sufficiently accurate historical knowledge of the construction vicissitudes. This work, mainly based on a polarising microscopy study (coupled with X-ray diffraction and SEM-EDS analyses) of over a thousand thin and ultra-thin sections of 400 microsamples, demonstrates that the current relicts of films are the result of alteration and decay of ancient treatments. In most cases, these were linseed oil-based glazings (the use of this substance is confirmed by historical documents) and pigments. Their role was essentially aesthetic; their use dates the beginning of the fourteenth century and continued at least until the eighteenth century.