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71.
广西桂平博物馆藏东汉铜甑对于研究广西地区青铜器冶铸技术的发展具有重要的研究价值。但器物长期保存于潮湿环境中,矿化严重、保存状况较差,亟须保护修复。本研究应用X射线影像观察、金相显微镜、扫描电镜及能谱分析、模拟实验验证等方法研究了器物的铸造工艺、合金成分以及锈蚀产物成分。结果表明该器物为整体铸造成形,器物铸造时使用了轮制技术、刮板造型工艺以及铸后刻纹的工艺,箅部范块制作过程是用器身模翻制器身范后脱模,将器身模的圈足部分切下,然后在圈足泥模上刻出箅部型腔。在此基础上,遵循最低限度干预原则,力求将传统的文物修复手段与现代修复理念相结合,通过除锈、修补等保护修复措施后,不但提高了器物的整体稳定性,而且达到了可以展陈,发掘文物潜在价值的要求。 相似文献
72.
L.F. Ramos A.C. Núñez García P.B. Lourenço 《International Journal of Architectural Heritage》2018,12(3):465-485
ABSTRACTThe “Quartel das Esquadras” is an 18th century infantry barrack located within the limits of the bulwarked fortress of Almeida, in Portugal. An ongoing adaptive reuse project of the building aims to recover its full capacity and also its importance, by implementing a variety of new uses. The architectural intervention results in the need of the structure to withstand new and diverse imposed loads. As the current configuration of the structure will be altered, the main objective of this article is to evaluate the suitability of some of the proposed structural interventions. The current condition has been characterized following a multidisciplinary approach comprising historical research, visual inspection, non-destructive testing, and structural analysis to identify the possible sources of major structural problems. A portion of the building particularly affected by the alterations has been selected to carry out structural analysis. A comparative safety assessment of the selected area in both current and altered condition has been done through finite element modelling and nonlinear static analysis, resulting in an identification of the weaker points against the new implemented loads and alterations. Finally, proposals for the implementation of the studied intervention, as well as recommendations for future research and analyses, have been given. 相似文献
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Several major cereal groups have been identified as staples used by the pre-urban, urban and post-urban phase populations of the Indus Civilisation (3200–1500 BCE): wheat, barley, a range of small hulled millets and also rice, though their proportional exploitation is variable across space and over time. Traditional quantification methods examine the frequency, intensity and proportionality of the use of these crops and help ascertain the ‘relative importance’ of these cereals for Indus populations. However, this notion of ‘importance’ is abstracted from the daily lives of the people using these crops and may be biased by the differential production (as well as archaeological survival) of individual cereals. This paper outlines an alternative approach to quantifying Indus cereals by investigating proportions of calories. Cereals are predominantly composed of carbohydrates and therefore provided much of the daily caloric intake among many late Holocene farming populations. The four major cereal groups cultivated by Indus farmers, however, vary greatly in terms of calories per grain, and this has an impact on their proportional input to past diets. This paper demonstrates that, when converted to proportions of calories, the perceived ‘importance’ of cereals from five Indus sites changes dramatically, reducing the role of the previously dominant small hulled millet species and elevating the role of Triticoid grains. Although other factors will also have affected how a farmer perceived the role and importance of a crop, including its ecological tolerances, investments required to grow it, and the crop’s role in the economy, this papers suggests that some consideration of what cereals meant in terms of daily lives is needed alongside the more abstracted quantification methods that have traditionally been applied. 相似文献
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76.
N. Noe-Nygaard 《Journal of archaeological science》1983,10(4):317-325
A vertebra of a Brown Bear (Ursus arctos) is described from the Mesolithic settlement Star Carr. This is the first record of the species from the site. The presence of Brown Bear in a Preboreal/Boreal deposit is an important addition to the early Mesolithic fauna of Britain. A comparison with contemporary Danish material shows that the bone from Star Carr falls within the wide size range of the Danish subfossil Brown Bear. In Denmark the species decreases in number from Boreal to Atlantic time, and finds are extremely scarce in Britain during the same time interval. This is probably due to the major eustatic sea level rise, which isolated Britain and Sjælland, preventing new immigration, and to vegetational changes restricting the preferred habitats of the Brown Bear. 相似文献
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78.
Assessing Socio‐Economic Vulnerability to Climate Change Impacts and Environmental Hazards in New South Wales and Queensland,Australia 下载免费PDF全文
This article systematically reviews and synthesises academic, peer‐reviewed literature to assess the state of knowledge concerning socio‐economic vulnerability to climate change impacts and environmental hazards in New South Wales and Queensland, Australia. It focuses upon empirical research that identifies socio‐economic factors associated with vulnerable subpopulations. Using systematic review methods, 35 articles met the inclusion criteria. These articles are analysed according to their general characteristics, the methods used, and the factors reported to be associated with socio‐economic vulnerability. This body of evidence reveals that (1) the majority of the knowledge about socio‐economic vulnerability in New South Wales and Queensland has only recently emerged; (2) more knowledge has been published about Queensland; and (3) extreme temperature is the most researched environmental hazard. Despite increased research activity over time, the number of factors repeatedly demonstrated to influence socio‐economic vulnerability is small. Age, gender, place of residence, and pre‐existing illness were the most commonly reported factors, although the influence of these factors upon socio‐economic vulnerability is complex. There is scope to extend the empirical research base across a broader range of climate‐related hazards and to better link findings from the domains of climate change vulnerability and population health. 相似文献
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80.
A Box Containing Carpenter's Accessories from The Akko 1 Shipwreck,Israel: Archaeometallurgical Analysis of Surviving Ironwork 下载免费PDF全文
The Akko 1 shipwreck was an Egyptian armed vessel, built at the beginning of the 19th century. A wooden saw handle and a box containing iron nails and two split pins were discovered towards the stern. Given their function, location and context, these were part of the ship's carpenter's tools and accessories. A methodology was developed for conducting systematic metallurgical analysis in order to understand the manufacturing process of the surviving ironwork items, as well as to enlarge our knowledge regarding ironworking technologies during the early 19th century. Such methodology may assist in the future understanding of the technological evolution of similar wrought‐iron objects. The results demonstrated that the artefacts have a wrought‐iron heterogeneous microstructure and were manufactured by hot‐working prior to surface hardening by pack carburization. 相似文献