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61.
水是造成砖石质文物劣化的主要因素之一,因此探明其在文物内部的分布、运移规律是开展保护研究的重要基础。微波技术在检测材料内部的水分含量方面表现出较好前景,但在文物保护领域还未普遍应用。基于此,本研究首先介绍了微波技术的理论基础和相关仪器,并选取山西省的长春玉皇庙为对象,针对砖石材料的内部含水率开展了室内样块检测和现场墙体检测。结果表明,微波技术能够较为准确地揭示出文物内部的空间含水率分布规律,这对于研究其病害成因等具有重要作用。此外,与其他多种无损检测技术相比,微波技术检测材料含水率的优点更多,值得文物工作者进一步研究与应用。 相似文献
62.
This study discusses the existence of a variability recorded in lateralization indexes of proximal microburins, a by-product of the individual manufacture of microliths, in a sample of Sauveterrian sites from the Italian Eastern Alps. At first glance, such variability may appear to support the existence of customary handling, pertaining perhaps to an ensemble of normalized technical procedures accomplished by the members of the human group regardless of site type, context and economic activities. However, plotting the patterns in lateralization index against the regional Sauveterrian chrono-cultural sequence reveals a diverse correlation emerges and indicates how the early settlement phase involved greater functional differentiation among sites used by selected human groups compared with the successive phases, when this pattern vanishes. This trend may correspond to the decrease in lateralization observed on skeletal markers from the Upper Paleolithic to the Mesolithic, linked to the change in technological models and techniques employed in food gathering. The implications of this research at different levels are also discussed. 相似文献
63.
Special iron objects in the form of a narrow plate with a fan-shaped blade on one or both ends, but with a substantial variation in shape and size, have continually been excavated from ancient historical sites located in the southern part of the Korean peninsula. The frequency and abundance of their excavation imply that they must have played a crucial role in the initial shaping of the Korean iron industry. Little is known, however, of their intended purposes or the exact engineering processes applied in their production. Speculation suggests that they might have been used as currencies or intermediate materials for the making of finished products. This study examined the microstructures of three such iron objects from the Korean Three Kingdoms Period (ca. 300–600 AD). It was determined that they were made of low carbon iron generally containing a number of non-metallic inclusions, with hints of surface carburization particularly at the ends of the plates. These results reveal the likely presence of an iron technology based primarily on the bloomery technique as opposed to the Chinese style of iron-making based on cast iron technology, which was also in use in ancient Korea. 相似文献
64.
《Journal of Geography in Higher Education》2012,36(1):135-149
The authors embed their advocacy of educational technology in a consideration of contemporary pedagogy in geography. They provide examples of e-learning from a wide range of teaching and learning contexts. They promote the idea that considering best practice with reference to educational technology will increase the versatility of teaching geography in higher education. On the basis of reviewing the pedagogic options associated with e-learning using a variety of technologies, and their promotion of versatility in the use of e-learning approaches, they find and illustrate the new spaces that have become available to teachers and learners of geography. 相似文献
65.
《History & Technology》2012,28(3):281-309
Prior to the launch of Sputnik, knowledge about human space travel was widely circulated by spaceflight proponents, scientists and news producers in mainstream culture through print, film and broadcast media and displayed in public sites such as museums and public exhibition spaces. Focusing on the timeframe 1947–1953, this article examines how key members of the British Interplanetary Society used a combination of craft skills, graphical technologies, and communication media to create pictures and models to support rhetorical claims that spaceflight and astronautics are legitimate fields of scientific research and space travel could and should be achieved in the near future. Production and circulation of factual knowledge about space travel was not confined to material and discursive practices in established fields such as astronomy and aeronautical engineering. Actors from other professional, non-professional, and social groups contributed to the realization of future spaceflight as an heterogeneous cultural endeavor or astroculture encompassing an array of technical processes, artifacts, craft skills, and scientific knowledge. 相似文献
66.
Sabrina B. Sholts Dennis J. Stanford Louise M. Flores Sebastian K.T.S. Wärmländer 《Journal of archaeological science》2012
Clovis points are the principal diagnostic artifacts of a Clovis complex that spread across North America between ca. 11,050–10,800 radiocarbon years before present. Clovis may be the best documented Paleoamerican culture in North America, but much remains to be learned about the movement and interactions of Clovis peoples. Similarities among Clovis points from geographically diverse locations have led some researchers to suggest that a uniform projectile point technology existed across North America during Clovis times. Others have rejected this idea, proposing local and independent technological adaptations to different regional environments. To investigate these ideas, we used digital morphometrics to analyze 50 Clovis points from nine different contexts. First, 3D surface models of the points were created with a portable laser scanner. Next, these models were digitally cross-sectioned through both faces, yielding two-dimensional isoheight contours of flake scar patterns that reflect the original reduction techniques used to shape the projectile points. In the final step, the contours were transformed with elliptic Fourier analysis into Fourier coefficient series, and patterns of variation and symmetry were explored with principal components analysis. When compared to modern Clovis point replicas made by an expert knapper, the flake scar contours of the ancient Clovis points showed little morphological variation and a large degree of bifacial symmetry. Our results support the existence of a widespread standardized “Clovis” knapping technique, most likely transmitted through direct interaction between knappers from different groups. 相似文献
67.
Mikael Nilsson 《European Review of History》2012,19(2):275-302
This article takes a close look at how the United States used the funding of scientific research in Sweden as a hegemonic and propaganda tool in the 1950s and 1960s. It shows that non-aligned Sweden functioned just as much as a node in the international science network set up by the Americans after the Second World War as did the North Atlantic Treaty Organization (NATO) countries. These funds were awarded mainly to an elite network of prominent Swedish scientists. The article sheds interesting light on the controversies of such funding in Sweden during the cold war and adds important knowledge about Swedish–American relations during the cold war. The article argues that this Swedish scientific elite co-produced US hegemony in Sweden by actively seeking out American military funding and by making use of it. It also argues that US funding was intended to portray the United States as an altruistic patron of science in the world and thus serve American propagandistic purposes as well. 相似文献
68.
毛志平 《中国文物科学研究》2012,(4):86-89
在现代修复理念的指导下,对一件战国镶红铜鸟兽几何纹青铜壶进行保护修复,通过分析检测与研究、制定修复方案、保护修复处理、装饰工艺等步骤,介绍了现代青铜文物保护修复的基本要求和流程,探讨了此件特殊工艺青铜器的修复工艺,对其精美纹饰和装饰工艺进行赏析,同时提出了保护修复后的保存建议. 相似文献
69.
为了更好地了解亚浸水漆器的制作工艺及材质,为该类文物修复保护提供科学依据,本工作采用扫描电镜能谱分析、X射线衍射分析、红外光谱分析等技术对出土于陕西长安县明代墓葬一漆棺的制作工艺及主要制作材料进行了分析研究。结果表明,漆棺是按照木胎-纤维-灰层-漆膜-颜料的工序制作的,主要使用材料有麻、粘土类物质、生漆、金及朱砂颜料。漆棺制作工艺及材质与文献记载基本一致,是中国古代漆棺传统工艺制作的典型代表。 相似文献
70.
This paper considers the transition from Howiesons Poort to post-Howiesons Poort technologies at the rock shelter site of Klein Kliphuis, South Africa. The transition at this site is shown to be gradual, with incremental changes in material selection and in the size and shapes of flakes and cores. Implements which appear to blend characteristics of those distinctive of the earlier and later industries appear briefly at the mid-point of the transition. The results suggest that there is unlikely to have been an occupational hiatus between the Howiesons Poort and post-Howiesons Poort. Explanations for the Howiesons Poort phrased in terms of population expansion and contraction are also difficult to support. Technological changes at this time may relate to environmental variation, though the limited nature of terrestrial archives documenting changes in resource productivity necessitate that any such suggestion be made with caution. 相似文献