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51.
The stable carbon and nitrogen isotope ratios of collagen of seven bones from each of three rabbits raised on a monotonous diet, and of two bones from each of eight female and seven male mink raised on another monotonous diet, were determined. The ranges of δ13C values and δ15N values were 0·5‰ and 0·6‰ for the rabbit bones and 1·0‰ and 1·4‰ for the mink bones. Uncertainties in the δ13C and δ15N values for prehistoric human diets estimated from the isotopic composition of collagen from the small numbers of bones which are typically available for analysis, and thus likely to be of the order of ±1‰.  相似文献   
52.
This article examines the kambārī vessel now housed at the Museum of the Frankincense Land, Salalah, Oman, built for display in 1980. This sewn‐plank boat type, used for fishing and lightering in Dhofar, is discussed in the context of other similar vessels in Oman, South Yemen, and Somalia. As one of only five known surviving kambaris, a detailed account of this vessel's construction is given accompanied by an accurate pictoral record.  相似文献   
53.
Abstract

In 1956, the government of the People’s Republic of China made a 12-year plan for scientific and technological developments (‘The Long-term Plan for the Development of Science and Technology for 1956–1967’), often credited as a visionary blueprint for its nuclear weapons programs and industrialization. Yet, this study suggests that the plan was not the logical manifestation of a unified national leadership, but rather the result of political contestations and compromises among the Communist party-state leaders, especially between Mao Zedong and Zhou Enlai, and between the state and the scientific–technological elite. It further indicates that the making of Chinese science and technology policy was shaped by the cold war geopolitics, national developmental aspirations and transnational influences, especially from the Soviet Union and the USA.  相似文献   
54.
Sections of human hair from naturally desiccated Sudanese Nubian mummies representing X-Group (AD 350-550) and Christian (AD 550-1300) periods in the Wadi Halfa area have been analysed for their isotope ratios. Because the carbon in hair represents food intake over the growth period of this tissue, analysis comparing segments taken next to the scalp with those further along the shaft can indicate diet just prior to death as well as any recent shift in food consumption. Modern populations in this area practise seasonal crop scheduling which involves the cultivation of C3 plants (wheat, barley and most fruits and vegetables) in the winter and the hardier C4 plants (sorghum and millet) in the summer. Shifting isotopic values along the length of hair strands of the ancient inhabitants of this area demonstrate that this practice has its roots at least as far back as the Initial Phase of Intensive Agriculture. The most common season of death appears to have been summer, the time of greatest climatic, nutritional and physiological stress for both ancient and modern inhabitants.  相似文献   
55.
Ginalski-type E5 button spurs made from a Cu alloy are a characteristic attribute of the Middle Roman period in barbarian Europe. The find of part of a mould made of non-ferrous metal at the Luleč site in the district of Vyškov, Czech Republic, provided key evidence for explaining the issue of their production. The discovery of this unique artefact showed that based on current knowledge, the spurs made from a Cu alloy were also produced in the Middle Danube region and not only in Northeast Europe as had previously been thought.  相似文献   
56.
3D打印技术已在多领域证明其高效性以及便捷性,成为社会热点。由于3D打印带有非接触式扫描的特点,这对于文物修复工作者而言,是在复制和修复过程中,为保护材质脆弱、价值珍贵的陶瓷类文物的可引进的新手段。在简单介绍3D打印技术复制陶器的主要过程之后,通过实例细致地了解每一个具体步骤,分析液化打印、粉末打印等不同打印技术的优缺点,如何在不同需求下进行选择;并且介绍在得到3D打印复制件后,通过复制件表面上色、纹饰加工处理等步骤完成整个复制品。3D打印技术不仅可被运用于文物复制,而且能以其与传统修复手法相比之下的无损、快速、精确等特点,在文物修复中发挥作用。  相似文献   
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58.
Most of the traditional boats still in use in Musandam, Oman, are essentially batātīl or zawārīq. Both types of vessel are described and compared in detail and placed within the larger context of boat types found in the surrounding region. This article attempts to establish a classification based primarily on shape, construction and decorative features, and provides names of individual components in both in Arabic and Kumzari.  相似文献   
59.
60.
During the completion of the expansion works at the Museum of Pontevedra (Spain), a stretch of about 60 m of the medieval walled enclosure surrounding the historic city centre was discovered. Due to its value as a heritage element, the discovery of this archaeological structure required the implementation of preservation activities and exhaustive documentation so that future generations will be able to know and enjoy this piece of history. This paper presents digital models that reproduce the original structure of the wall using close‐range digital photogrammetry, as well as orthophotos, which thoroughly document the dimensional and textural characteristics of the archaeological site. In addition to analysing the accuracy and validity of photogrammetry in the conservation of archaeological heritage, a methodology of data capture, processing and photogrammetry representation is evaluated.  相似文献   
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