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21.
14C测定判别武王克商年代范围始末   总被引:1,自引:0,他引:1  
武王克商年代是我国古代编年中的一个关键点,近年来^14C测定技术有了重要发展,我国^14C测年界在此基础上探讨了^14C方法应用于商周历史纪年的希望。1996年夏商周断代工程正式立项,利用^14C测定判别武王克商年代范围的任务得以实施。1998年初两个常规^14C实验室以3‰测定精度,前后开始对陕西丰镐遗址出土样品^14C测定,并于1998年10月6-7日先后公布了^14C数据,提出武王克商代范围应判别在公元前1050-1020年间。1998年下半年AMS室开始测定。三室测定数据对比结果基本相合,利用殷墟,琉璃河等遗址出土的样品系列作^14C测定得出的结果,与上述年代范围一致。1998年11月30日公布了天计算结果,与测定结果不谋而合,经多方面反复验证,历时近二年,都无法动摇已有的判别结果,具有较高的可信度。  相似文献   
22.
C地点共清理墓葬37座,为圆角长方形土坑竖穴墓,多数墓葬为单人仰身直肢葬。随葬品主要是陶器,器物组合以筒形罐和壶为主,还出土石器、骨器、玉器等。C地点墓葬的文化内涵与此前发掘的A、B两地点新石器时代墓葬应属同一种文化,可暂称为南宝力皋吐类型。  相似文献   
23.
This paper describes the numerical simulation of the seismic behaviour of a mock-up of a six-floor building, constituted by two parallel R/C walls and experimentally tested on a shaking table. Within the scope of an international benchmark the mock-up was submitted to three earthquakes with intensities up to 0.71 g, which induced nonlinear behaviour in the concrete and reinforcement. For the numerical simulations concrete is discretised with 2D finite elements, and its behaviour reproduced via a constitutive model with two scalar damage variables. Steel rebars are discretised with 2-noded truss elements, and their constitutive behaviour under cyclic conditions reproduced by the Menegottb-Pinto model. Specific attention is devoted to Rayleigh damping, focusing on two different strategies: (i) disregarding the damping contribution, or (ii) adopting a damping matrix that takes into account the stiffness changes during the nonlinear analyses. Main results and strategies for simulating the benchmark axe presented, with emphasis on the comparison between the numerical and the experimental results, which show good agreement when the damping contribution is neglected.  相似文献   
24.
Abstract

Middens of the southern British late Bronze and Iron Age are vast accumulations of cultural debris that can be explained as refuse dumps linked with large periodic feasting events. A distinctive feature of these sites is that their faunal assemblages invariably comprise a considerably higher proportion of pig remains than contemporaneous settlement sites. This paper presents results from a programme of stable carbon (δ13C) and nitrogen (δ15N) isotope analysis of fauna from two major midden sites, Llanmaes in South Wales and Potterne in Wiltshire. The research aim is to reconstruct husbandry strategies and foddering regimes, particularly concerning pigs, to better understand how the challenges of raising large herds were met. Analysis produced exceptionally wide-ranging results for pigs and other domesticates at both sites, particularly in terms of δ15N values, demonstrating that diverse foddering strategies were employed. Diversity in the late Bronze Age pig foddering regimes indicates that the Neolithic husbandry practices (focusing on woodland fodder) had not been abandoned, but that new husbandry methods (consumption of household waste) were also being practised, which subsequently became more widely established in the Iron Age. The heterogeneity of signatures suggests that animals may have been husbanded in a piecemeal fashion at a local, household level. This in turn hints that fauna may have been brought to these sites from households across the surrounding landscape, rather than being husbanded by specialist producers in the vicinity of the middens.  相似文献   
25.
This article deals with the translations of Old French works completed at the court of Hákon Hákonarson, king of Norway. The first one was probably completed in 1226 and some 40 followed: translations of epic poems, courtly romances and lais, adventure romances and a fabliau. In all cases, we ought to speak of adaptations and not of word-for-word translations.

Together, these literary works form an outstanding corpus, elaborated mainly for didactical purposes and in order to support Hákon Hákonarson's project to build a monarchy à l'européenne. For that, some literary works were selected and – in their adaptations – some ethical and social values promoted while some others were not; and some great literary works were intentionally ignored and remained untranslated.  相似文献   
26.
This paper presents direct evidence of subsistence practices and pottery use at a Late Neolithic site at al-Basatîn, northern Jordan. Measurable concentrations of C16:0 and C18:0 were recovered from 8 of 10 archaeological pottery fragments through use of a microwave-assisted silica gel and aminopropyl solvent protocol developed for the isolation and concentration of free fatty acids in marine sediments. Subsequent isotopic analysis of the surviving C16:0 and C18:0 saturated fatty acids revealed ∂13C ratios consistent with those of adipose fats of ruminant and non-ruminant animals pastured on lands adjacent to the Jordan Valley. The high recovery of diagnostic compounds from the al-Basatîn material is discussed in context of a wider examination of the initial development and use of pottery in the Fertile Crescent, and the emerging debate concerning the efficacy of stable carbon isotope values in characterizing organic residues embedded in pottery fragments recovered from the earliest ceramic horizons in the Middle East and Europe.  相似文献   
27.
新中国诞生后,百废待兴。冀朝鼎在帝国主义实施禁运和经济封锁的困难面前,积极探索中国外经贸的新体制,加强外汇管理,以灵活的外交,与11个国家签定了外贸协定,还成功地与日本、英国等未建交国家进行“民间贸易”.打破西方列强的孤立政策.开创了中国对外交往与贸易的新局面。  相似文献   
28.
科默·V.伍德沃德在美国是享有盛誉的南部史专家,同时也是一位非常活跃的社会活动家。在长期的学术实践中他形成了注重史学的社会功能、强调历史发展的非连续性和善用反讽的史学研究风格。他以自己对美国南部历史与现实的深切关怀,积极推动了南部史的研究。其贡献既表现在对新的史学领域和问题的开拓,也体现在围绕他的著述所展开的学术商榷、学术批评中,以及由此而形成的良性的学术研究氛围上。  相似文献   
29.
本报告发表的是中国社会科学院考古研究所考古科技实验研究中心碳十四实验室和中国科学院地球环境研究所西安加速器质谱测试中心在2007~2011年期间测定的40个考古数据。数据表示方式与以往所发报告相同。为方便应用另做如下几点说明。1.碳十四年代半衰期按5568年计算。2.校正年代所用程序为OxCal,校正曲线为1998年公布版本。3.与以往报告相同,所给年代误差范围均为±16,年代范围的概率分布为68.2%。4.由于树轮年代校正曲线各区段形状不同,校正后年代范围可能形成几组,总合概率为68.2%(与过去报告中总合概率表示为100%相同)。5.校正均按单一样品方式处理。6.数据均作碳十三  相似文献   
30.
It is now three decades since Waterbolk introduced evaluation criteria to 14C chronology. Despite this, and other subsequent attempts to introduce quality control in the use of 14C data, no systematic procedure has been adopted by the archaeological community. As a result, our databases may be significantly weakened by questionable dates and/or questionable associations between dated samples and the archaeological phenomena they are intended to represent. As the use of chronometric data in general becomes more ambitious, we must pause and assess how reliable these data are. Here, we forward a set of evaluation criteria which take into account archaeological (e.g. associational, stratigraphic) and chronometric (e.g. pre-treatment and measurement) criteria. We intend to use such criteria to evaluate a large 14C dataset we have assembled to investigate Late Glacial settlement in Europe, the Near East and North Africa, supported by the Leverhulme Trust. We suggest that the procedure presented here may at least form the basis of the development of more rigorous, scientific use of 14C dates.  相似文献   
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