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This article describes a novel, small-scale nonlinear beam-column connection and an associated six-story frame test structure for the experimental dynamic response investigation of multi-story buildings subjected to earthquake loading. The objective is to create a re-configurable, reusable experimental platform on which several aspects of nonlinear dynamic response can be investigated through successive, exhaustive testing under suites of earthquake records. Static and dynamic calibration tests demonstrate excellent test-to-test repeatability of four structure configurations. These results confirm that the properties of each configuration (period, strength, energy dissipation) remain invariant, thus allowing future experimental investigations (e.g., of peak engineering demands) under earthquake loading. 相似文献
364.
C. Tribolo N. Mercier E. Douville J.-L. Joron J.-L. Reyss D. Rufer N. Cantin Y. Lefrais C.E. Miller G. Porraz J. Parkington J.-P. Rigaud P.-J. Texier 《Journal of archaeological science》2013
Diepkloof Rock Shelter offers an exceptional opportunity to study the onset and evolution of both Still Bay (SB) and Howiesons Poort (HP) techno-complexes. However, previous age estimates based on luminescence dating of burnt quartzites (Tribolo et al., 2009) and of sediments (Jacobs et al., 2008) were not in agreement. Here, we present new luminescence ages for 17 rock samples (equivalent dose estimated with a SAR-ITL protocol instead of classical MAAD-TL) as well as for 5 sediment samples (equivalent dose estimated with SAR-single grain OSL protocol) and an update of the 22 previous age estimates for burnt lithics (modified calibration and beta dose estimates). While a good agreement between the rock and sediment ages is obtained, these estimates are still significantly older than those reported by Jacobs et al. (2008). After our own analyses of the sediment from Diepkloof, it is suspected that these authors did not correctly chose the parameters for the equivalent dose determination, leading to an underestimate of the equivalent doses, and thus of the ages. 相似文献
365.
Lauren M. Cleeland Mason V. Reichard Raul Y. Tito Karl J. Reinhard Cecil M. Lewis Jr. 《Journal of archaeological science》2013
This paper reports an approach to the identification of prehistoric parasitic infection, which integrates traditional morphological methods with molecular methods. The approach includes the strengths of each method while mitigating the limitations. Demonstrating the efficacy of this approach, we provide a case study from a 1400 year old desiccated fecal sample from La Cueva de los Muertos Chiquitos, archaeological site, near Rio Zape, Durango, Mexico. Traditionally prepared microscope slides were processed via microscopy and tentative ascarids were identified. Information regarding the parasites' developmental stage was recorded. DNA was then extracted directly from the slide material. From this DNA extract, a small segment of the 18S ribosomal RNA gene variant that is specific to Ascaris, and its phylogenetically close relatives, was targeted for PCR amplification and sequencing. Phylogenetic analysis of the DNA sequence best matched a member of physalopterids, rather than ascarids, with a single exception of a match to Contracaecum spiculigerum. Subsequent extractions, amplifications and sequencing of the original rehydrated coprolite material confirmed these results. The C. spiculigerum sequence represented a phylogenetic anomaly and subsequent analysis determined the sequence was an error in the BLAST database, likely attributable to misidentification of juvenile specimens prior to sequencing and submission. Physaloptera are a difficult genus to identify morphologically and can carry major health burdens. They may be underreported in humans, in part, because of morphological similarities to the more common human parasites belonging to ascarids. We conclude that integrating traditional morphological methods with molecular methods can help resolve this issue, in both contemporary and prehistoric populations. 相似文献
366.
Y.S. Volkova 《Archaeology, Ethnology and Anthropology of Eurasia》2013,41(3):33-39
Principal stages in the manufacture of zoomorphic, polyiconic, and anthropomorphic Upper Paleolithic figurines are reconstructed. General factors determining their characteristics include universal conventions of representation and the limited set of technological operations available, whereas local factors include specific ways of processing materials and combining artistic techniques, the manner of individual masters, technological faults and accidents, as well as taphonomic processes. 相似文献
367.
Y.S. Hudiakov K.Sh. Tabaldiev A.Y. Borisenko K.T. Akmatov 《Archaeology, Ethnology and Anthropology of Eurasia》2013,41(3):81-86
The article addresses the topic of composite bows from nomadic sites in Tien Shan and Zhetysu. Horn plates from bows discovered in 2008–2009 at Uch-Kurbu on the Tosor River, the Issyk-Kul Depression (Kyrgyzstan), are described and analyzed. The original design of the wooden core of the bow and the location of horn plates thereon are reconstructed. Based on our earlier classification of weapons, these are composite bows of the Xiongnu-Xianbei period. Two subtypes are identified, based on the design of plates at the ends of the bow. Evidently, composite bows with end, medio-lateral, and medio-frontal plates were the most efficient range weapon of the period. 相似文献
368.
Y.S. Hudiakov S.G. Skobelev O.A. Mitko A.Y. Borisenko Zh. Orozbekova 《Archaeology, Ethnology and Anthropology of Eurasia》2013,41(1):104-113
Excavations at the Bai-Dag I cemetery, the Eerbek River valley, Tuva, have revealed a burial rite typical of the Aldy-Bel culture, Early Scythian period. Above-ground and underground structures, principal features of the burial rite, and burial goods are described with regard to sex and age. Basic trends in the evolution of early nomadic funerary ritualism in Tuva are reconstructed. 相似文献
369.
The salt chimney effect: delay of thermal evolution of deep hydrocarbon source rocks due to high thermal conductivity of evaporites
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Half of the topseals to the world's largest oilfields are evaporites. Rock salt has a thermal conductivity two to four times greater than that of other sedimentary rocks found in oil‐ and gas‐bearing basins. Strong heat conduction through evaporites can increase the geothermal gradient above evaporite deposits, resulting in a positive thermal anomaly and above‐average temperature while simultaneously decreasing the geothermal gradient below evaporites, resulting in a negative thermal anomaly. Most Triassic–Jurassic hydrocarbon source rocks in the Kuqa Basin, western China, are overlain by ~1500‐m‐thick Tertiary evaporites with underlying Cretaceous sandstones and mudstones. Directly measured strata temperatures indicate an obvious break in the steepness of the geothermal gradient above and below Paleogene evaporites, with a significantly steeper geothermal gradient above the evaporites. Simulations of the thermal evolution of source rocks based on data collected from well Kela‐2 indicate that if the thickness of evaporites (mainly rock salt and anhydrite rock) in overlying rocks above source rocks increases compared with the thickness of siliciclastic rocks in the overlying rocks, then strata temperatures and vitrinite reflectance in Jurassic source rocks will decrease accordingly. Our thermal simulations based on the thickness and thermal conductivity of evaporites accurately coincide with previous studies based on homogenization temperatures, hydrocarbon–water contact retrospection, and carbon isotope results from natural gases. The gas generation center located in the Kalasu Tectonic Belt today is also sealed in an evaporite‐related structural trap that formed at this time. Therefore, the speculated natural gas generation times not only correlate with the evaporite‐related structural trap formation, but the calculated maturity of deep source rocks below the evaporites also coincides with current gas reserves. And our studies can help to find the deep oils and gases under thick evaporites. 相似文献
370.
Comparison of the Different Types of Qinghua Porcelain from Jingdezhen in the Yuan Dynasty of China (ad 1271–1368) by Micro X‐ray Fluorescence Spectroscopy (μ‐XRF) and Microscopy
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The Yuan Qinghua porcelain produced in the city of Jingdezhen, in China, mainly includes the gaudy blue type, a blue–grey or grey‐coloured type and the type featuring a blue colour with a slight amount of grey. For a long time, only the gaudy blue type was focused on and discussed, while the other two types, which contain equally important information with regard to recovering the manufacturing technology of Yuan Qinghua, were always ignored by scientific researchers. In this paper, by using micro X‐ray fluorescence spectroscopy (μ‐XRF), spectrophotometry and optical microscopy, all three different types of Yuan Qinghua porcelain are analysed systemically and, based on the analyses of the body, the glaze and the blue decoration, the differences in the materials and the manufacturing technologies of the three different types are discussed. This not only provides a good basis for the reconstruction of the whole picture of the manufacturing process of Yuan Qinghua porcelains in Jingdezhen, but also contributes to database‐building for the identification of Qinghua porcelain. 相似文献