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51.
关于夏商周碳十四年代框架 总被引：6，自引：2，他引：4
中国历史教科书将翻开新的一页,因为新的夏商周三代年表公布了,它将中国有确切纪年的历史向前推进了 １２２９年。 由历史学、天文学、考古学和Ｃ测年技术等学科的２００多位专家参加的我国建国以来社会科学领域规模最大的科学研究项目—夏商周断代工程,历经４年多的时间,终于实现了既定的目标,建立了三代年表。这标志着我国在年代学方面的研究又迈上了新的台阶。 夏商周三代年表从西周共和元年的公元前８４１年到公元前２０７０年跨越中国早期的三个朝代,总年数长达１０００多年,中间涉及了许多重要的年代定点和时段。其复杂性、其… 相似文献
52.
The influence of masonry infills with openings on the seismic performance of reinforced concrete (R/C) frames that were designed in accordance with modern codes provisions is investigated. Two types of masonry infills were considered that had different compressive strength but almost identical shear strength. Infills were designed so that the lateral cracking load of the solid infill is less than the available column shear resistance. Seven 1/3 – scale, single–story, single–bay frame specimens were tested under cyclic horizontal loading up to a drift level of 40%. The parameters investigated are the opening shape and the infill compressive strength. The assessment of the behavior of the frames is presented in terms of failure modes, strength, stiffness, ductility, energy dissipation capacity, and degradation from cycling. The experimental results indicate that infills with openings can significantly improve the performance of RC frames. Further, as expected, specimens with strong infills exhibited better performance than those with weak infills. For the prediction of the lateral resistance of the studied single-bay, single-story infilled frames with openings, a special plastic analysis method has been employed. 相似文献
53.
This paper presents evidence for increased recovery of organic residues from archaeological pottery through use of a microwave‐assisted liquid chromatography protocol. C16:0 and C18:0 saturated fatty acids were obtained from archaeological potsherds recovered from nine Neolithic settlements in the Middle East dating between 4700 and 7300 cal bc , including materials that had not produced evidence for the survival of any lipid species through use of ‘conventional’ solvent extraction techniques. Compound‐specific isotopic analyses of C16:0 and C18:0 fatty acids in potsherd extracts subsequently revealed δ13C/δ12C compositions consistent with modern subcutaneous fats of wild boar and goats pastured on lands adjacent to the Jordan Valley, and residues from a modern pottery vessel used in the manufacturing of butter, cheese and yogurt in central Turkey. These results are presented as an illustration of capabilities of the microwave‐assisted recovery protocol. The reclamation of saturated and unsaturated fatty acids from archaeological pottery fragments recovered from a number of the earliest ceramic horizons in the Middle East is herewith reported, and the extraction methods and instrumental analytical techniques are described. 相似文献
54.
We have applied and refined methods for the determination of bulk hydrogen, carbon and oxygen isotope ratios in modern and archaeological resins. The modern resins have a wide range of isotopic values and vary within the same tree, between individual trees, with species and location. For all isotopes measured, there is a general trend of increasing depletion of the heavier isotope with increasing altitude. There is also a linear trend between depletion of δD and δ13C values with increasing latitude; this trend is less clear for oxygen, but is related to the meteoric water line. Two case studies using archaeological resins known or suspected to have been transported in antiquity have been investigated to determine whether isotopic signatures can assist in pinpointing the geographical origin of the resin: Pistacia sp. resin from Canaanite amphorae imported into Egypt from known geographical locations in the eastern Mediterranean during the Late Bronze Age, and Roman amphorae sherds lined with Pinus sp. resin from sites ranging from Britain to the eastern Mediterranean. These results show separate groupings between the two resin types (pine/pistacia) and between the modern/archaeological resins. Some archaeological samples are distinct from the others and the modern resins show differences between geographical areas. However, there are no clear patterns relating the different Canaanite fabrics or the suggested manufacturing site of the Roman amphorae. 相似文献
55.
This article deals with the roles of ambiguity and discretion in the governing of migration and how they contribute to the marginalisation of migrants at the borders of EUrope. Building on ethnographic research and interviews conducted in Sicily, it connects legal-institutional ambiguities of two recent policy interventions in the field of migration governance in Italy – the Security Decree-Law and the Hotspot Approach – to the discretionary practices by public officials tasked with their implementation. By theoretically and empirically tracing the co-constitutive relationship of ambiguity and discretion, the article draws on and contributes to recent inquiries into grey areas of governance, particularly in the field of (critical) border regime studies. Based on two distinct cases, it analyses how ambiguity and discretionary local practices are related both to each other and to the contemporary fragmentary reconfiguration processes of the EUropean Migration and Border Regime, and shows how they intersect to form spatio-juridical grey areas that foster the spatial and social marginalisation of migrants in EUrope. 相似文献
56.
ABSTRACT In this paper, we analyze the isotopic niche and resource use of the guanaco (Lama guanicoe), pampas deer (Ozotoceros bezoarticus) and marsh deer (Blastocerus dichotomus) on the temperate plain of the northern Pampa region in the southeast of South America. The measured stable isotope compositions in bone tissue are δ13C, δ15N and δ18O. All the analyzed samples were recovered from different archaeological sites from the late Holocene. According to the results, the guanaco was strictly confined to the Pampa plain environment, developing a broad niche based on C3 plants and a variable contribution of C4 grasses within a grazing trend. The pampas deer preferentially used the Pampa plain, but also the prairies on the borders of the wetland, showing eurioic characteristics and a narrower niche based on C3 plants. In turn, the marsh deer was strictly confined to wetland environments, developing a C3 diet–base, within a narrow isotopic niche and stenoic characteristics. The three mammals showed a wide range of intraspecific variability, which was a key factor in their adaptability to spatial and temporal changes in the vegetation coverage. In fact, the temporal trends of their isotopic values were concurrent with the major climatic variations of the Holocene. Differences in the correlations between the values of both carbon sources in both deer species compared with the guanaco suggest a distinct chemical composition of their diet and/or differences in the allocation of nutrients. The isotopic values of nitrogen and spacing of the carbon sources in guanaco (pseudoruminant) and both deer species (ruminants) show no significant differences between them, thus establishing the values for local large herbivores. Significant correlations between δ13C and δ15N were found in the guanaco and marsh deer. The regional and extra–regional variability in the guanaco's δ13Ccollagen and δ15N probably reflect the clinal variations in the vegetation coverage and the amount of rainfall. The collagen isotope values in the guanaco throughout the entire Holocene show that the humid Pampa would have shifted between being a more recurrent mesic and temperate plain with minor phases of dry–mesic conditions like during the Little Ice Age, and a humid and warm one at the peaks of the Holocene Thermal Maximum and the Medieval Climatic Anomaly. The guanaco and the pampas deer adapted to all the climatic changes that happened on the humid Pampa until the biological invasions of large European mammals changed the herbivores’ guild composition of this vast plain, pushing them into peripheral habitats due to competition. The within–species variability in isotopic signals through time and space make it necessary to carry out adequate sampling before reconstructing the diets of local past populations. 相似文献
57.
Tamer Koralay Mehmet Oruç Baykara Kıymet Deniz Yusuf Kağan Kadioğlu Bahadır Duman Chuan-Chou Shen 《Environmental Archaeology》2019,24(3):317-336
The coloured stones used in buildings and monuments were an indicator of power and wealth during the ancient times. In this study, Tripolis city samples have been compared with Tripolis quarry samples in order to recognise the provenance of the banded travertine blocks in the ancient city. The banded travertine samples have similar mineral compositions and mainly consist of calcite with minor amounts of dolomite, aragonite, clay and iron oxide minerals. These results are also supported by CRS studies. Calcite is in the form of needle-shaped crystals ranging between 0.163–1.418?mm (in city) and 0.303–1.270?mm (in quarry). Tripolis banded travertine samples show the similar compositional spread in terms of major oxide, trace elements. δ13CV-PDB values of banded travertines range from 1.93 to 5.25‰ (in city) and 2.99 to 3.99‰ (in quarry), δ18OV-PDB values change between (?16.93)–(?10.08) ‰ and (?15.93)–(?13.01)‰, respectively. The U–Th radiometric ages are determined between ～267 and 9?ka in Tripolis city samples and ～350 and 2?ka in Tripolis quarry samples. The minero-petrographic, geochemical, C–O and U–Th isotope results fairly matched with each other. It seems highly probable that the banded travertines in Tripolis city were extracted from the Tripolis quarry, which is located at the northeast of the antique city with a distance of 3?km. 相似文献
58.
The region of the Central and South Andes was, in about the ninth and 15th centuries ad , the stage for the development of political systems tending towards demographic centralization in villages with defensive structures, known as Pucará. The chronological accuracy for these phenomena still remains uncertain, mainly because it involves intervals of long and superimposed occupations, masked by the Inca domination. Thus, this paper analyses the history of the occupation at Pucará de Tilcara, one of the biggest populated centres of the Humahuaca Gorge (Quebrada de Humahuaca, Argentina). Twenty‐five radiocarbon dates are critically evaluated to judge its reliability. The Bayesian statistics show that all the dated spaces were used on a long‐term basis. The most ancient signs are in the middens and relate at least to the 10th century ad , and the occupation of the housing areas could be calculated to the 13th and 16th centuries. A phase of higher intensity of occupation is observed during the Inca period. This redefinition of this site occupation shows the need to statistically analyse the dates in order to differentiate the phases of occupation. 相似文献
59.
Martin Rudwick 《Interdisciplinary science reviews : ISR》2016,41(2-3):268-277
Beginning with my recollection of hearing C. P. Snow's ‘Two Cultures’ lecture, I sketch my experience of building two academic careers in succession, first in one of the natural sciences and later in the history of such sciences. I outline both the difficulties and the rewards that I encountered in crossing the alleged gulf between the sciences and the humanities, but also emphasise the diversity of cultures that I experienced within each. I describe my own encounter with the academic culture of continental Europe, within which the concept of a monolithic singular ‘Science’ could be dismissed as an ‘anglophone heresy’, and viewed from which the Two Cultures debate could seem both provincial and redundant. 相似文献
60.
Frank A. J. L. James 《Interdisciplinary science reviews : ISR》2016,41(2-3):107-117
The notion of the existence of two opposed cultures, one literary and one scientific, has a long pedigree going back to nineteenth century. However, it was C.P. Snow's formulation of the idea in 1959 and F.R. Leavis's 1962 critique, which brought it to the fore in cultural discourse, where it has more or less remained ever since. The papers in this special double issue of Interdisciplinary Science Reviews examine the debate and its legacies from a variety of perspectives, while this introduction seeks to contextualise the issues raised and draw some contemporary lessons. 相似文献