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981.
982.
X.‐Q. Chen  B. Zhang  Z. Zhang 《Archaeometry》2019,61(6):1417-1429
Because it is often difficult to preserve fragile relics in situ at underwater cultural heritage sites, it is sometimes necessary for relics to be extracted and moved to a controlled environment on land for protection and study. This paper discusses the feasibility of using the volatile organic compound veratraldehyde as a temporary consolidant for underwater fragile relics extraction. The results show that different materials (iron, tile, sand, wood) under water can be bonded together and extracted when using veratraldehyde. The fact that veratraldehyde is difficult to spread on the surface of underwater objects is a problem that can be solved by adding a layer of strong hydrophobic polypropylene (PP) fibres onto the object, serving as a ‘package' for the relics. Under laboratory conditions, we used veratraldehyde and PP fibres to extract broken tiles from underwater sand onto an exhibition stand. The broken tiles, in both condition and distribution, were safely and completely retained as the veratraldehyde was slowly removed by the soaking process. This work fills a gap in knowledge about temporary consolidant materials in underwater archaeology, and provides a new method for extracting underwater fragile cultural relics without damaging them.  相似文献   
983.
The application of solid state electrochemistry techniques for the characterization and dating of leaded bronze objects is described. Characteristic voltammetric signatures of copper and lead corrosion products were used as markers of more or less prolonged corrosion periods. The proposed methodology was applied to samples from the Roman archaeological sites of Valeria (Spain) and Gadara (Jordan), Roman and medieval sites in Xàtiva (Spain), and modern statuary exhibited outdoors, on the campus of the Universitat Politècnica of Valencia, Spain, covering a time interval between the fourth to second century bc and the 20th century ad . For such samples, the ratio between the signals for copper and lead corrosion products decreased monotonically with the corrosion time. This variation was modelled on the basis of thermochemical and kinetic considerations, the experimental data being consistent with a potential rate law for the corrosion process.  相似文献   
984.
2011年,联合国教科文组织亚太遗产保护委员会在泰国曼谷授予中国贵州安顺鲍屯明代水利工程保护项目亚太遗产保护“卓越奖”。这是亚太遗产保护的年度最高奖项,共有10个国家34个项目参与竞争。评委会对这一乡村水利工程保护项目的评价是:  相似文献   
985.
The extraction of silver has traditionally been considered as one of the main incentives for the Phoenician expansion throughout the Mediterranean and their settlement in Iberia. In this paper, we approach the organization of silver production in Iberia during the Early Iron Age through the study of the evidence of production currently available and the development of Lead Isotope Analysis (LIA). Previous results (Hunt 2003; Stos Gale 2001; Kassianidou 1992) are considered in the light of new data. The extraction of silver from complex minerals noticeably intensifies in south‐west Iberia. Imports of exogenous lead, needed for the extraction of silver from these complex minerals, are evident. Supplies of lead come in from other regions of Iberia, such as Gádor, Cartagena/Mazarrón, Linares or even the mining district of Molar‐Belmunt‐Falset (MBF) in Catalonia. This picture reveals that the organization of silver production was much more complex than initially thought, with the articulation of an exchange network of raw materials at a macro‐territorial scale embracing almost all Iberia. The socioeconomic implications that control of these networks of lead distribution could have had are also discussed.  相似文献   
986.
987.
The increasing scope of the Internet into all spheres of life has become an added burden for educators, requiring that they incorporate Internet use into the school curriculum. Exploiting the Internet to support the educational process presents an opportunity as well as a challenge. A plan to support the Arabic curriculum has been presented at the Al‐Bayan Bilingual School. Its potential success and adoption by other schools represents an opportunity for improving the educational process in Kuwait.  相似文献   
988.
989.

Ida Blom (ed.), Cappelens kvinnehistorie, vol. 1: urtid, oldtid, middelalder til ca. 1500, vol. 2: renessanse, reformasjon, revolusjon ca. 1500 til i dag, vol. 3: Asia og Afrika. Tredje verden (Women's history, vol. 1: prehistoric times, antiquity, the Middle Ages until 1500, vol. 2: renaissance, reformation, revolution from 1500 to now, vol. 3: Asia, Africa. The Third World). (Oslo: Cappelens forlag AS, 1992–1993), 448 pp., 638 pp., 351 pp. ISBN 82–02–14078–1.

Johan Söderberg, Civilisering, marknad och våld i Sverige 1750–1870. En regional analys (Civilization, market, and violence in Sweden 1750–1850. An analysis of regions). (Stockholm: Almqvist &; Wiksell International, 1993). 290 pp. ISBN 91–22–01543–4.

Jean‐Pierre Mousson‐Lestang, La Scandinavie et l'Europe de 1945 à nos jours (Presses universitaires de France 1990).  相似文献   
990.
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