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排序方式: 共有803条查询结果,搜索用时 15 毫秒
1.
古人发型是文化界长期关注的一个重要现象。发型不仅是时代的特征与时尚的符号,也是各个族群的辨识标志。从北朝到隋唐的中古社会,"剪头胡雏"的文物图像屡屡出现,一般来说,此类胡人形象是剪发而不是束发,在当时以"高髻为尚"的社会习俗中,"剪头胡雏"发型是有着"阶级感"的存在,是有关底层胡人的直观艺术产物。也说明当时入华胡人还没有彻底"汉化",仍然保留着本族群的发型特征。该发式是胡人与汉人的区别,也是其身份归属的象征。 相似文献
2.
In recent years, bio-energy with carbon capture and storage (BECCS) has been awarded a key role in climate mitigation scenarios explored by integrated assessment models and referenced in reports by the Intergovernmental Panel on Climate Change. Because a majority of scenarios limiting global warming to 2 °C or 1,5 °C include vast deployment of BECCS, a critical discussion has emerged among experts about the moral implications of thus introducing an unproven technology into the policy realm.In this paper, we analyse this discussion as it has played out between 2013 and 2019, with a focus on how expert narratives are constructed in the mass media about the possibilities for decarbonisation within the current political-economic order. We find there are almost no narratives that support massive deployment of BECCS, and that all narratives presuppose limits to decarbonisation imposed by the current political-economic system. The perception of such limits lead some to argue, through deterministic and apolitical narratives, for the necessity of negative emissions technologies, while others argue instead that “degrowth” is the only solution. Thus, there is a distinct lack of positive narratives about how capitalism can bring about decarbonisation. 相似文献
3.
浑仪、简仪(以下简称两仪)在高PH、大气污染和日晒雨淋环境中的腐蚀是一种动态加速腐蚀过程。采用合成的双唑胺铜缓蚀剂和有机硅改性的甲基丙烯酸树脂,并分别复配成协同缓蚀剂群和含有增效稳定剂的封护剂。采用这两种材料和脱水后再防护的工艺,使带锈防护后的浑仪、简仪的腐蚀低于无污染大气中的速率。用电化学方法评价了防护技术的可行性,根据腐蚀与人工老化试验结果讨论了防护材料性能与腐蚀环境和带锈防护的关系,采用XPS分析方法探索了双唑胺比BTA更适用于两仪防护的原因。 相似文献
4.
C. F. W. Higham 《International Journal of Historical Archaeology》1998,2(3):235-260
The Early Historic Period in the Mun Valley occupies a critical three centuries, from A.D. 500 to A.D. 800, a period often known as that of Zhenla, a name derived from early Chinese accounts. This article first describes early findings of fieldwork designed to illuminate the prehistory of the upper Mun Valley, a period which covers approximately two millennia, with initial settlement now dated between 1500 and 1000 B.C. It then considers the nature of the transition to the complex polities of Zhenla. This involves a combination of archaeological and documentary evidence. Sources for the latter are rare for the Mun Valley, but by broadening the area considered, it is possible to integrate archaeological and historical sources in order to portray the intensifying social changes which characterize the Early Historic Period. It is suggested that most of the Mun Valley was occupied by Khmer speakers during the Iron Age, people responsible for the transition to increasingly centralized polities of the Early Historic Period. In the upper reaches of the Mun catchment, and in the Chi Valley to the north, the late prehistoric inhabitants spoke Mon. They had close affinities with the Dvaravati polities of Central Thailand. If confirmed, this hypothesis would indicate a series of local trends towards increasing social complexity which we can recognize in the early epigraphic record. 相似文献
5.
Stephen J. Shennan 《Journal of World Prehistory》1993,7(2):121-161
The chronology of the period is briefly considered in the light of the dendrochronological results which have appeared in recent years. Patterns of settlement history in different parts of the area are then examined, and it is suggested that in some of them the late fourth millennium was a period of population decline which was not reversed until the Early Bronze Age, 1000 years later. Detailed information about specific local occupation patterns is provided by recent work on the circum-Alpine lake villages. Changes in cultural patterns during the period, especially the appearance of the Corded Ware, are discussed and explanations of them reviewed. It is argued that changing patterns of gender relations were a major feature of the period, linked to processes which eventually led to the development of small-scale chiefdoms. The development of copper and bronze metallurgy and its connection to these processes are discussed. 相似文献
6.
Improvements in Archaeomagnetic Dating in Western Europe from the Late Bronze to the Late Iron Ages: An Alternative to the Problem of the Hallstattian Radiocarbon Plateau
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We present a new curve of the directional secular variation of the geomagnetic field in Western Europe between 1500 bce and 200 ce . Its computation relies on a Bayesian framework. The fast secular variation during the Late Bronze and Early Iron Ages makes archaeomagnetic dating efficient with a respective precision of 150–200 and 60–100 years during these periods. The Bayesian method also provides posterior date distributions that refine the dating of reference data, especially during the period of the Hallstattian radiocarbon plateau. Archaeomagnetism becomes a valuable alternative to radiocarbon and will help to improve the archaeological chronologies. 相似文献
7.
The architecture of the Iron Age II fortified settlement at Muweilah (Sharjah,United Arab Emirates)
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Steven Karacic Marc Händel Emily Hammer Peter Magee 《Arabian Archaeology and Epigraphy》2018,29(1):27-54
Excavations at Muweilah have uncovered twelve buildings encircled by two pairs of walls and ditches. We have published preliminary studies of several buildings. Research has now progressed to a stage where it is possible to produce a more complete analysis of the architecture. In this report, we present a detailed discussion of the fortifications and each building with its installations. Our assessment of the architecture identified the repeated combination of three rooms in many of the buildings in the Central Area of Muweilah. Moreover, a detailed study of the fortifications revealed several means of accessing Building II, the columned hall, in the Western Area. These findings offer insights into the organisation of Iron Age II settlements in south‐eastern Arabia. 相似文献
8.
滕州前掌大墓地中随葬兵器的墓葬较多,特别是女性墓葬中随葬兵器的现象较之于其他地区更为多见亦罕见于海岱地区。产生这种现象的原因可能与商末周初时女性社会地位较高和前掌大地处战事频繁的东夷重地有关,也许正因如此,前掌大墓地的女性生前可能参与作战。 相似文献
9.
In this paper, we propose a free-standing structure that is unanchored to its foundation and has a cost-efficient interface consisting of common construction materials (steel, mortar, and iron) with graphite lubrication; this structure is expected to behave as an earthquake-resistant structure during small earthquakes and a base-isolated structure during large earthquakes. To realize the structure, this study examined the frictions of the interfaces in shaking table tests. In addition, the seismic responses of the free-standing structures based on the interfaces were examined via incremental dynamic analyses with 44 ground motions and a simple model of typical Japanese steel structures. 相似文献
10.
Matilde Eiroa 《Central Europe》2018,16(1):1-16
After the Second World War, anti-communists of different backgrounds from Central and Eastern European countries decided to settle in Franco’s Spain, where they sought safety and a place to live during the Cold War. This article will provide an overview of their political profiles and assess the reasons these exiles chose Spain, a country excluded from the United Nations until 1955 and led by Francisco Franco. The article also shows how they settled in the dictatorship linked to the Nazis and Italian Fascists, and the ways in which they continued their struggles against Communism with public and private resources. 相似文献