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1.
The concentrations of two major elements and thirteen trace elements in 73 selected sherds of fine grey ware from the Iron Age and Roman period, excavated at Conimbriga, Santa Olaia and Tavarede, Portugal, were determined by instrumental neutron activation analysis. These concentrations were used to calculate distance matrices which were then subjected to cluster analysis employing SAHN and k-means methods, as well as to principal components analysis, to group the sherds according to the overall similarity of their compositional characteristics. The results showed that equivalent groupings appeared regardless of the taxonomic method used. Two major clusters were recognized corresponding to two different sites, namely Conimbriga and Santa Olaia, suggesting that the ceramics from these sites were made locally. No significant differences in compositional patterns were observed between iron age and roman sherds from Conimbriga.  相似文献   
2.
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   
3.
The site of Kharaib al-Dasht, located on the northern coast of Failaka, is a late Islamic settlement with an extensive fishing infrastructure. It has been excavated since 2013 by the Kuwaiti-Polish Archaeological Mission. The ceramic assemblage collected so far exceeds 18,000 fragments. The sherds underwent technological and typological analyses, which demonstrated a wide diversity of local common kitchen wares, consistent with the needs of households specialised in fishing. A considerable percentage of imported vessels was brought to Failaka from the Arabian Gulf and Persia, though Far Eastern luxury tableware was also attested. This paper demonstrates the socioeconomic role of Kharaib al-Dasht in the context of trade exchange on the microregional (Kuwait) and macroregional (the Gulf, South and Eastern Asia) scales in the eighteenth and nineteenth centuries.  相似文献   
4.
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   
5.
The results obtained from the multi-analytic compositional characterization of ceramic pastes and paints of the Santa María style, from the El Bolsón valley (Belén Department, Catamarca Province, Argentina), are presented here. This pottery style had a wide regional distribution in Northwestern Argentina between ca. 1000 and1600 ce and is characterized by its complex iconography painted in black, cream and red. The analyses show that the containers correspond to the technical tradition of using grog temper and suggest that its manufacture involved a double firing process. This reveals a new practice for the time.  相似文献   
6.
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   
7.
南宁市房地产业经历了由沉寂、复苏、火爆到稳步发展的过程.各公司开发的房屋类型相近,但价格差异却很大,价格分布呈现明显的规律性:一是城市中心价格高,边缘与郊区价格低;二是东部城区价格高,西部城区价格低.主导价格分布规律的三大影响因子是地理位置、交通便捷程度和生态环境质量.南宁今后的房地产开发和城市规划建设一要顺应价格分布规律,优地优用、保障房地产开发的高效益;二要加强交通设施建设和环境保护.促进全市房地产的升值;三要因势利导,发展城市副中心,逐步形成多中心的城市建设格局。  相似文献   
8.
ABSTRACT

This research report aims to give detailed information on the pottery from the 1999 and 2013-16 excavation campaigns taking place at the Tell Sufan site in Nablus, Palestine. These were conducted by the Department of Antiquities at An-Najah National University (ANU) in Nablus. It is of note that this ancient pottery has never previously been the subject of research nor has any literature been published on it. Our methodology consists in: analysing the pottery by identifying it, typifying it, and giving it a function; providing chronological information on the site; comparison of the pottery with that from other sites in Palestine, using archaeological information from the site; and contextualising our findings with other historical and archaeological studies. Examination of the functional use of the pottery allows us to demonstrate human activity at the Tell Sufan site, giving information on the most prosperous phases of occupation in regard to economic aspects, through the late Bronze Age, Iron Age and Byzantine-Early Islamic periods.  相似文献   
9.
10.
岭南僻处南疆,地理复杂。隋末大乱之时,地方势力纷纷割据,唐初和平统一岭南后,采取羁縻政策,以原有势力为基础设管州的"都府"。而在都府之上,朝廷以广州、桂州、交州为中心置"统府",以点控面,有效地维护了岭南地区的稳定。但是这种层层管理的"统府三分格局",到高宗乾封二年发生突变,随着邕府和容府的建立,原统府消失,遂形成并立的"五府格局"。可是,最迟8世纪初,唐朝设立岭南五府经略使,统一管理整个岭南的军事。在此前后,岭南选补使、岭南按察使、岭南采访使等陆续出现,在人事、监察、民政等领域,对岭南道全境实施管辖权。因此,"盛唐"的岭南道,表现出明显的"归一"趋势。  相似文献   
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