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11.
Accelerator mass spectrometry (AMS) allows radiocarbon dating to be carried out by direct counting of14C atoms, rather than the conventional counting of radioactive disintegrations. The result is that samples up to 1000 times smaller can be handled. The approach was tested in principle by 1977 and for archaeological operation by 1983. More than 2000 samples per year are now being dated worldwide. The machines can now operate to about ± 80 years or better. Dates older than 40,000 years have not yet been achieved, but the ability to use small samples has already had considerable impact on dating the period 10,000–30,000 years ago. Bone is an ideal material for the new technique, since amino acids can normally be isolated and purified from gram-size samples. Studies of the origins of domestication are aided by the dating of individual grains and seeds. Because small samples can be mobile in the soil, careful sample selection strategies and procedures are required. The full impact of the technique can be assessed only through the rapid and comprehensive publication of archaeological results.  相似文献   
12.
周滔  张璞洁 《人文地理》2023,38(1):118-129+157
乡村振兴要求走乡村内生性发展道路,客观认知乡村发展能力的时空分异格局和交互关系对乡村振兴战略实施具有重要意义。本文从农业产业发展、农村基础建设和农民社会生活三个维度构建测度指标体系,并引入面板向量自回归模型识别影响乡村发展能力的敏感因素,以此测度乡村发展能力指数,进而采用探索性时空数据分析方法揭示乡村发展能力的时空交互特征。结果表明:(1)我国中部地区多维乡村发展能力提升,但呈明显的空间异质性,不同维度间差异化显著;(2)中部地区多维乡村发展能力局域空间格局呈现较强的动态性并整体表现出较强的空间依赖关系;(3)邻接地级市多维乡村发展能力的时空交互网络以正向关联为主,局部空间呈差异化的竞合态势。  相似文献   
13.
In the late Middle Ages there are two different conceptions of experience: a non-religious, exterior experience, derived from physical perceptions: the Aristotelian conception, and a religious, interior experience: the conception of monastic theology, represented by Bernhard of Clairvaux. In the transition from Middle Ages to modern times the distinction between exterior and interior experience is transferred into the religious experience.  相似文献   
14.
The chemical and mineralogical characterization of seven ceramic fragments produced within Tiwanaku state (c.500–1000 ce ) is reported. The instrumental techniques used included X‐ray elemental and mineralogical chemical analysis, Raman spectroscopy, and scanning and light microscopy. The results indicate there are several clay types, although they show similarities, such as the use of a plant‐based temper. The red colour of the decoration is hematite, and manganese oxides such as jacobsite are present in the black. The white colour is a mixture of gypsum and clay, and the orange is a mixture of hematite and clay. The use of colours, the quality of the clays and the temperatures reached during pottery firing point to expertise in ceramic production and to complex decision‐making processes. The multi‐elemental archaeometric approach documented here could become an important tool to shed a light on ancient ceramic technology and the internal variance of Tiwanaku pottery.  相似文献   
15.
Most research on urban planning, policy and development only considers legal practices and actors, and treats illegal ones as insignificant anomalies, unable to structurally affect the governance of urban space. However, this approach is inadequate for explaining urban governance in contexts (e.g. several countries in the Global South, the former Soviet bloc and Southern Europe) where illegal practices such as corruption and organized crime infiltration are widespread in many public and economic sectors. This paper addresses the role of illegal actors and practices in urban governance in the Italian context, using urban regime theory as the theoretical frame of reference. The research centres on the analysis of two case studies in the city of Rome (the In-between world investigation of a criminal network that had infiltrated the local administration and shaped several urban policies, and the investigation of episodes of corruption related to the project for the new A.S. Roma soccer stadium). It shows the existence of two shades of ‘grey urban governance’: firstly, the presence of a dark urban regime, centred on a criminal organisation and parallel to the ‘regular’ one; secondly, the use of corruption as a customary practice with which real estate entrepreneurs influence municipal decisions. Overall, this research contributes to moving away from a rhetoric of ‘gentlemanly’ urban capitalism and politics, and suggests the need to revise several aspects of urban regime theory – as well as other approaches to urban governance dynamics in general – in order to incorporate the role of illegal actors and practices.  相似文献   
16.
Based on qualitative data collected in two different Belgian cities (Brussels and Liège), this article focuses on the emergence of civil society initiatives to address the grey zones of migration and integration governance in the country. We define the concept of grey zones as situations that appear in specific time-spaces where problematic issues arise and the state fails to intervene. This triggers the intervention of civil society to deal with specific governance issues. In Belgium, the state – through an indifference-as-policy approach – delegates the responsibilities of reception and integration policies to multiple actors and leaves space for a variety of citizens’ initiatives to emerge. The grey zones of government policies become spaces for possible citizen-organised actions aimed at both providing initial reception and legal support to migrants, and denouncing the absence of state intervention. These citizen actions operate in particular on the issue of housing and reception of forced migrants with different legal status and migration aspirations. We also highlight the ambivalent relations emerging between civil society actors and the state. Through the analysis of two situated case studies, this article aims to provide evidence on how these civil society initiatives develop and how their humanitarian approach becomes political.  相似文献   
17.
This article examines the intense debates over the New Criminal Code of Great Qing (Da-Qing xin xinglü) in the National Assembly (Zizheng yuan) during the Qing empire’s New Policy Reform (1901–11). The focus is on the conflict between those who drafted and supported the new code and those who expressed reservations, especially over reform of the laws on filial piety and fornication. The issue of reconfiguring the family and social order through law was closely related to the overarching agenda of twentieth century legal reform in China—making an empire that “ruled through the principle of filial piety” into a modern nation-state that had direct relationships with its citizens. More importantly, an analysis of the late Qing debate over family law enables this article to problematize such concepts as “Chinese” and “Western” during this crucial moment of China’s empire-to-nation transformation. It showcases the paradox of China’s modern-era reforms—a contradiction between imposing Western-inspired order with a largely indigenous logic and maintaining existing sociopolitical order in the name of preserving national identity.  相似文献   
18.
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   
19.
聚醋酸乙烯酯(PVAc)乳液是常见的彩绘类文物保护材料。采用激光粒度仪、热重/差热分析、红外光谱、X-射线衍射、扫描电镜、透射电镜等表征了PVAc乳液的粒径以及胶膜的热稳定性、结构和形貌;采用粘度计、表面张力仪、pH计、电导率仪等研究了乳液浓度与其粘度、表面张力、pH、电导率的关系;通过冻融、室温-高温放置、离心分离研究了乳液的稳定性;同时用PVAc乳液对模拟起甲和酥碱的壁画进行了修复。结果表明,PVAc乳液粒径呈双峰分布,小粒子的平均粒径为380 nm,大粒子的平均粒径为5.85μm;乳液胶膜为非结晶物质,胶膜热重的最终质量残留为1.54%,335℃出现放热峰。PVAc乳液的电导率随浓度的增大而增大,pH随浓度的增大而下降;相同温度下表面张力随浓度的增大而基本呈现低浓度下降,高浓度上升的趋势。相同浓度下,表面张力随温度升高而无显著变化,表明PVAc乳液的表面张力受温度变化影响不大。相同温度下,乳液粘度随浓度的增大而增大;相同浓度下,乳液的粘度随温度的升高而降低。冻融、离心分离和不同温度下静置发现,该乳液出现分层。用该乳液对模拟起甲和酥碱壁画修复后,再分别老化20个循环和12个循环,发现颜料层再次空鼓、起甲。综合分析,说明实验中所使用的该种PVAc稳定性和抗老化能力较弱,在修复彩绘类文物中应慎重选择PVAc的种类,综合考虑PVAc的使用浓度、环境因素对其性能的影响,以达到最佳使用效果。  相似文献   
20.
The selection of a non-shattering phenotype is a pivotal change in the process of rice domestication. However, current research is heavily restricted by the preservation conditions of macro-plant remains in early and middle Neolithic sites, as very limited well-preserved rice spikelet bases could be retrieved. We present a non-destructive method based on micro-computed tomographic (CT) scanning, which could provide detailed visualization of the internal structures of charred spikelet bases and efficiently discriminate the shattering and non-shattering phenotypes of rice spikelet bases according to the abundance of fusiform echinate phytoliths. It could be widely applied in different contexts, especially those poorly preserved specimens and tempers in pottery sherds, greatly improving our knowledge of rice domestication.  相似文献   
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