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1.
Kuwait–Georgian archaeological work at Failaka Island showed the need for geological study. Analysis of sediments related to drinking water-collecting cisterns was performed on a Late Islamic settlement (NE part of the island) in 2018. Field sedimentological, grain size and XRD analysis of the sediment profiles showed that the shallow (about 1 m deep) cone-shaped wells are dug in the loose, porous, cross-stratified calcareous coarse-grained quartz sandstones. Three upper layers of quartz sandstones in the profile have high infiltration rate and provide a rare yet ideal material for water retention. The fourth dense layer below, composed of very fine sand and silt fraction, tends to hinder water movement and forms a relatively impermeable water-resistant surface. Thus, the distribution patterns of clay content, grain sizes and porosity of the well-hosting sediments are favourable for freshwater infiltration and harvesting. An additional petrographic analysis was conducted on different types of rocks discovered on the archaeological site, used as building material and fragments of stone artifacts to identify their origin. It was established that archaeological building material is of local origin, whereas the source rocks for stone artifacts were imported.  相似文献   
2.
王哲 《历史地理研究》2021,41(2):119-138
近代中国邮政空间主要是以民信局、国营邮政、侨批等多种企业实体构成。清朝邮政成立后即开始蚕食小额民间资本支持下的民信局经营空间,而基于对1936年《中华民国邮政舆图》的数字化工作发现,历经40余年经营,国营邮政基本整合了全国范围内的邮政空间,也基本完成了本领域的“国进民退”。在此过程中,国营邮政审慎模仿民信局的经营方式,使用多种创新经营策略,除了在大中城市内部和城市之间构建了便捷快速的邮政网络空间,更借助邮政代办的方式以极低的成本将营业网络“下沉”到铁路和公路无法覆盖的农村地区,较好地与传统农村“定期市”网络完成耦合,基本达到了通商处必通邮的效果。国营邮政点和邮路集聚所形成的“邮政聚集区”也成为一种显著的近代化外在空间表征,同时成为界定所谓“核心—边缘”结构的系统可信、定量可验证的空间指标。  相似文献   
3.
四川省馆藏文物保存环境监测区域中心(简称四川区域中心)平台,经过两年多的运行实践,实现了12家博物馆监测站的集成联网。本研究分析了区域中心监测平台运行中常见故障现象的表现形式、故障原因及故障率。结果表明:监测平台的主要故障现象为传输异常和数据异常;除温湿度外的其他监测终端故障率较高;软件平台建设也不够完善,导致数据利用率低,尚不能实现风险评估、预测预警和预防调控等管理功能。针对分析发现的问题,提出一些相应的技术措施和管理措施,为有效降低故障的发生率,提升国内区域中心平台建设提供一定的指导和参考。  相似文献   
4.
Many factors governed the penetration efficacy of prehistoric projectile weaponry. Archaeologists broadly focus their efforts on understanding the effect of stone weapon tips because these specimens are often the only part of the weapon system that survives in the archaeological record. The tip cross-sectional area (TCSA) and perimeter (TCSP) of stone weapon tips have been shown to correlate with target penetration depth. Here, using results from both static and dynamic penetration testing, we compare TCSA and TCSP against other tip geometry metrics: lateral surface area (LSA) and volume (V). Our analyses broadly show that using a single-point geometry metric evaluated at multiple locations along the length of the point, or using multiple geometry metrics evaluated at a single location, better predicts required energy than using a single-point geometry metric evaluated at a single location. Our results also show that in the case where a single geometry metric evaluated at multiple locations is used LSA provided the most robust prediction models. Finally, our results show that for the case where all geometry metrics evaluated at a single location are used the location that provides the most robust prediction model is dependent on how far the point penetrated the target.  相似文献   
5.
汉代漆器的剖析   总被引:2,自引:2,他引:0  
通过制备并分析一系列模拟漆膜样品。建立了有助于鉴定汉代漆器成分的剖析方法。经裂解气相色谱、差热分析、色谱一红外联用等现代分析技术对出土的汉代漆器残片样品的综合分析,证实在西汉漆器制造中已使用桐油或其它的添加剂,并依据剖析的结果,对某些汉代漆器的原材料差异作了初步探讨。  相似文献   
6.
We use trace element discrimination diagrams to provide a geochemical fingerprint for Tufo Lionato, the volcanic rock most commonly used in the ancient Roman dimension stone technique. Based on the comparison of their geochemical signatures, we identify different rock facies of Tufo Lionato employed since the fourth to third centuries and through the second century bce in the construction of the temples of the Area Sacra di Largo Argentina. These rock facies correspond to two previously identified building stones: Aniene Tuff and Monteverde Tuff, named after their supposed source areas located in the Aniene River Valley and in the homonymous locality of the Tiber River Valley, respectively. However, the results of our study demonstrate previous misidentification of these volcanic rocks in the different construction phases of Temple C, providing a revision of the dating system currently accepted for the diffusion of Tufo Lionato architecture. We show that the Aniene facies has been exploited since the end of the fourth century bce and that it was employed along with Tufo Giallo della Via Tiberina in the podium and staircase of Temple C, whereas observations at Largo Argentina suggest that the ‘Monteverde Tuff’ was only sporadically used in the early phases of the dimension stone construction technique.  相似文献   
7.
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   
8.
Alongside the institutionally constructed European identity, research shows that insights into citizens’ sense of belonging are valuable as well in assessing questions of identity. The tendency to conflate European identity with EU identity has spurred debates about the components that underlie European identification. The online subsidiarity adopted by the EU through e-platforms has allowed for a new form of citizenship where e-citizens (de)legitimate the issues under debate. This article examines the contents of European and national identities in the e-debaters’ comments posted on the Debating Europe platform. Drawing on narrative and discursive approaches, we propose a framework to operationalize the (de)legitimation and identification categories used by e-debaters within their discursive construction of European identity. The qualitative empirical research shows three main (de)legitimation clusters: the “EU as a loss,” “inclusive gain,” and “exclusive gain.” We discuss these findings within the broader context of Europeanization, identity multiplicity, and the conditions of the EU enlargement policy.  相似文献   
9.
In debates over post‐capitalist politics, growing attention has been paid to the solidarity economy (SE), a framework that draws together diverse practices ranging from co‐ops to community gardens. Despite proponents’ commitment to inclusion, racial and class divides suffuse the SE movement. Using qualitative fieldwork and an original SE dataset, this article examines the geospatial composition of the SE within the segregated geography of Philadelphia. We find that though the SE as a whole is widely distributed across the city, it is, with the exception of community gardens, largely absent from poor neighborhoods of color. We also identify SE clusters in racially and economically diverse border areas rather than in predominantly affluent White neighborhoods. Such findings complicate claims about the SE's emancipatory potential and underscore the need for its realignment towards people of color and the poor. We conclude with examples of how the SE might more fully address racial injustice.  相似文献   
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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