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排序方式: 共有235条查询结果,搜索用时 15 毫秒
81.
R. E. WOOD T. F. G. HIGHAM T. DE TORRES N. TISNÉRAT‐LABORDE H. VALLADAS J. E. ORTIZ C. LALUEZA‐FOX S. SÁNCHEZ‐MORAL J. C. CAÑAVERAS A. ROSAS D. SANTAMARÍA M. DE LA RASILLA 《Archaeometry》2013,55(1):148-158
Torres et al. (2010 ) published a series of radiocarbon, AAR, ESR and OSL dates from the site of El Sidrón, northern Spain, which is notable for the discovery of the partial remains of 12 Neanderthals. Whilst the non‐radiocarbon methods suggested an age beyond 32 600–46 300 years, direct radiocarbon dates on the human fossils were inconsistent, ranging between 10 000 and 50 000 bp . This study uses the ultrafiltration pre‐treatment protocol to obtain a date of 48 400 ± 3200 bp (OxA‐21 776) on a bone fragment and confirm the antiquity of the Neanderthal assemblage. Moreover, it demonstrates the comparability of the ultrafiltration and ninhydrin bone radiocarbon pre‐treatment protocols, and highlights the need for appropriate screening methods where valuable collections with poor biomolecular preservation are sampled for collagen extraction. 相似文献
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83.
CARLOS R. GONZÁLEZ 《Alcheringa: An Australasian Journal of Paleontology》2013,37(1-2):169-185
González, C. R., Early carboniferous Bivalvia from western Argentina. Alcheringa 18, 169–185. ISSN 0311-5518. Lower Carboniferous deposits of western Argentina yield invertebrates and plant remains. In the Tournaisian epoch, a transgression from the ‘Pacific’ flooded the Rio Blanco Basin, forming a semi-restricted inland sea. Marine invertebrates of this age comprise the Malimanian fauna, which is based on the Protocanites-Rossirhynchus Assemblage. Eleven species of Bivalvia are here described Palaeoneilo subquadratum sp. nov., Malimania triangularis gen. et sp. nov., Phestia sp., Volsellina? sp. Posidoniella malimanensis sp. nov., Leptodesma? sp., Schizodus sp., Cypricardinia? sp., Edmondia? sp., Sanguinolites punillanus sp. nov., and Vacunella? sp. nov. They are accompanied by gastropods, trilobites, conularids and corals. The Malimanian fauna is regarded as a poorly to moderately varied assemblage that was influenced by some basinal restrictions. It was probably connected to faunas of Chile and Peru, and lived during a stage of mild climate before the beginning of the Late Palaeozoic ice age. 相似文献
84.
Andrej Čerňanský 《Alcheringa: An Australasian Journal of Paleontology》2013,37(1):131-136
?erňanský, A. & Hutchinson, M.N., 2012. A new large fossil species of Tiliqua (Squamata; Scincidae) from the Pliocene of the Wellington Caves (New South Wales, Australia). Alcheringa, 1–6. ISSN 0311-5518. We describe an isolated frontal bone referable to a new species, Tiliqua laticephala (Scincidae), from the Pliocene Big Sink doline of the Wellington Caves, central eastern New South Wales, Australia. The bone is very robust, is unusually broad and thick, especially around the bases of the subolfactory processes and represents a large and heavily built lizard. The fossil has multiple fragmentary osteoderms in the frontal region, showing asymmetry in shape and thickness that do not correspond to the more regularly arranged anterior head shields of other scincoids. The specimen shares two unusual character states with extant Tiliqua, especially the large armoured species, T. rugosa. Other large skinks related to T. rugosa (other Tiliqua spp., Corucia zebrata, Egernia cunninghamii, Bellatorias major, Liopholis kintorei) are less similar in terms of frontal shape, thickness, sculpture, osteoderm ornamentation, and positioning of adjacent bones. 相似文献
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This paper shows the results of two passive experiments carried out at the European Volvi test site where a scaled building has been constructed. The first experiment was performed to study the motion of the structure excited by two small earthquakes. For one month, six strong-motion recorders were installed within the structure, at the top and at the basement. The analysis of the deformation of the structure has been assessed by computing the spectral ratio between the top and the bottom, with a special focus on soil-structure interaction. An analytical model was then proposed to reproduce the structure and soil-structure system behaviour. The soil-structure interaction was accounted for by using impedance functions. During the second experiment, we concentrated our efforts on the effect of the building vibration on the surface ground motion. An explosive shot was fired and several strong-motion recorders were installed on the ground close to the structure that allowed us to clearly identify a monochromatic wave coming from the building, in the time and frequency domains. This experiment allows us to demonstrate the non-negligible effect of the soil-structure-soil interaction that may disturb the surrounding ground motion. 相似文献
88.
YOSHIMITSU FUKUSHIMA CATHERINE BERGE-THIERRY PHILIPPE VOLANT DAPHNÉ-ANNE GRIOT-POMMERA FABRICE COTTON 《Journal of Earthquake Engineering》2013,17(4):573-598
Strong ground motion close to a fault can be expected to be very large, so its estimation is essential for human safetv. Although a few strong-motion data exist for the west Eurasian region, we proposed in a previous work [Berge-Thierry et al., 2003] an attenuation relation for spectral acceleration using strong-motion data recorded in west Eurasia (mainly in Europe) and some in the western United States: this relationship was derived for the French Safety Rule, which is applied for seismic hazard assessment at nuclear power plants. In this study, we propose a constraining of the amplitude saturation term related to the proximity of the fault, and an adding of an amplitude saturation term in the regression model. We add, to the data-set previously used to derive the west Eurasian attenuation relationship strong-motions recorded during recent large earth-quakes: the 1995 Hyogo-ken Nanbu (Kobe) event in Japan and the 1999 Kocaeli (Izmit) event in Turkey. The regression analysis, adopted from Fukushima and Tanaka [1990], is non-linear, so an iterative procedure is applied. The determined regression coefficients lead to a prediction of a peak ground acceleration of about 0.7 g for soil site conditions at a fault distance of 0.5 km. The Q coefficient deduced, from the distance coefficient is in agreement with scattering Q models. The introduction of the saturation term leads to significantly lower predictions of average spectral accelerations at short distances as compared with using the Berge-Thierry et al. [2003] empirical model. 相似文献
89.
Mohammad Ghavidel-Syooki David H. Evans Mansoureh Ghobadi Pour Leonid E. Popov J. Javier Álvaro Utkyr Rakhmonov 《Alcheringa: An Australasian Journal of Paleontology》2013,37(4):530-549
Ghavidel-Syooki, M., Evans, D.H., Ghobadi Pour, M., Popov, L.E., Álvaro, J.J., Rakhmonov, U., Klishevich, I.A. & Ehsani, M.D., 15.5.2015. Late Ordovician cephalopods, tentaculitides, machaeridians and echinoderm columnals from Kuh-e Faraghun, High Zagros, Iran. Alcheringa 39, 530–549. ISSN 0311-5518.Late Ordovician (Katian, uppermost Acanthochitina barbata to Armoricochitina nigerica chitinozoan zones) cephalopods, tentaculitides, machaeridians and echinoderms are documented for the first time from the southern Zagros Ranges. A low-diversity cephalopod fauna includes Geisonocerina dargazense sp. nov., Isorthoceras sp. cf. I. bisignatum (Barrande) and other undetermined orthoceratides. The presence of Late Ordovician tentaculitides in the high- to mid-latitude margins of Gondwana has been documented previously, but no examples have been described in detail. Thus, Costatulites kimi sp. nov., which currently occurs associated with brachiopods characteristic of the Svobodaina havliceki (brachiopod) Association, represents the earliest undoubted record of tentaculitides in Gondwana. Machaeridians constitute a relatively common component of the Late Ordovician benthic faunas from the Mediterranean margin of Gondwana, but no previous records on the Gondwanan Iranian-Arabian segment have been reported. Three echinoderm taxa based on dissociated columnals are documented from the Armoricochitina nigerica chitinozoan Zone, including Sumsaricystis radiatus Stukalina, Ristnacrinus sp. and Rosulicrinus rosulus Stukalina.Mohammad Ghavidel-Syooki [m_ghavidelsyooki@yahoo. com] Institute of Petroleum Engineering, Technical Faculty of Tehran University, PO Box 11365-4563, Tehran, Iran; David H. Evans [david. evans@naturalengland. org. uk], Natural England, Suite D, Unex House, Bourges Boulevard, Peterborough PE1 1NG, UK; Mansoureh Ghobadi Pour* [mghobadipour@yahoo. co. uk], Department of Geology, Faculty of Sciences, Golestan University, Gorgan, Iran; Leonid E. Popov [leonid. popov@museumwales. ac. uk], Department of Geology, National Museum of Wales, Cathays Park, Cardiff CF10 3NP, UK; J. Javier Álvaro [jj. alvaro@csic. es], Instituto de Geociencias (CSIC-UCM), c/ José Antonio Novais 2, 28040 Madrid, Spain; Utkyr Rakhmonov, Kitab State Geological Reserve, 9 Ipak Yuli Street, Sakhrisabz, Uzbekistan; Inna A. Klishevich, Department of Historical Geology, Geological Faculty, St Petersburg State University, Universitetskaya Naberezhnaya 7/9, 199034 St Petersburg, Russia [inna@IK4848. spb. edu]; Mohammad H. Ehsani [mh_ehsani@hotmail. com], Institute of Petroleum Engineering, Technical Faculty of Tehran University, PO Box 11365-4563, Tehran, Iran. *Also affiliated with Department of Geology, National Museum of Wales, Cathays Park, Cardiff CF10 3NP, UK. 相似文献
90.
Jaume Valentines–Álvarez 《History & Technology》2013,29(3-4):235-258
ABSTRACTThis paper explores the role of Catalan industrial engineers in the making of a stateless nation (within Spain) in the interwar period. After the proclamation of the Second Spanish Republic (1931–1939), a home rule for Catalonia was established. In this context, the members of the Barcelona Association of Industrial Engineers developed a techno–nationalist program with the double goal of both making technology Catalan and making Catalonia technological. As an alleged ‘third class’ between the working and ruling classes, industrial engineers sought to use their expertise in scientifically managing the workshop to organize the whole nation. They participated in professional initiatives and official institutions from which they spread the ‘factory ideals’ beyond the factory, such as efficiency, rationalization and statistical monitoring. This paper focuses on the nationalist and technocratic engagement of two leading (and politically diverging) industrial engineers: socialist Estanislau Ruiz-Ponsetí and liberal Josep M. Tallada. 相似文献