首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   344篇
  免费   20篇
  2024年   2篇
  2023年   4篇
  2022年   2篇
  2021年   4篇
  2020年   6篇
  2019年   12篇
  2018年   33篇
  2017年   30篇
  2016年   22篇
  2015年   20篇
  2014年   14篇
  2013年   69篇
  2012年   11篇
  2011年   13篇
  2010年   12篇
  2009年   13篇
  2008年   5篇
  2007年   4篇
  2006年   1篇
  2005年   3篇
  2004年   2篇
  2003年   2篇
  2002年   4篇
  2001年   3篇
  2000年   4篇
  1999年   2篇
  1998年   2篇
  1997年   6篇
  1996年   4篇
  1995年   5篇
  1994年   5篇
  1993年   3篇
  1992年   4篇
  1991年   3篇
  1990年   6篇
  1989年   7篇
  1988年   3篇
  1987年   4篇
  1986年   8篇
  1985年   1篇
  1984年   1篇
  1983年   1篇
  1982年   2篇
  1981年   1篇
  1975年   1篇
排序方式: 共有364条查询结果,搜索用时 178 毫秒
101.
102.
The role of coastal resources in the subsistence strategies of Palaeolithic human populations has only recently become an important topic in Old World archaeology. Information on the exploitation of these resources, both as foodstuffs and symbolic elements, can be used to infer the emergence of modern human behaviour as well as to track the diversification and intensification of human diet over time. The excavations carried out at El Cuco rockshelter, located in northern Spain have provided evidence for the exploitation of marine resources during the Early Upper Palaeolithic. The accumulation of Patella shells at El Cuco provides the largest accumulation and the first clear evidence of collection and consumption of molluscs during the Aurignacian on the Atlantic Façade of Europe. A deposit of ornamental shells appeared in a very homogeneous context dated to the Gravettian, suggesting that the shells belonged to the same item. The analysis of this evidence has allowed us to conclude that marine resources were systematically used at least from the beginning of the Upper Palaeolithic in the region. However, a comparison with the Mesolithic shows that intensive shellfish gathering did not occur until the end of the Upper Palaeolithic. Regarding the ornaments, it is interpreted that the identified shell beads were used as social or personal status markers.  相似文献   
103.
In 2009, an archaeological intervention in the Valle da Gafaria (Lagos, Portugal) allowed the excavation of part of a leprosarium and an associated necropolis (15th–17th centuries). The individuals recovered were buried directly in the soil, in positions and orientations discordant to the prevailing Christian rules. The sample is made up of eleven adult individuals of both sexes.  相似文献   
104.
Two equid species have been documented in the Pleistocene of the Iberian Peninsula, the horse Equus caballus, and the Eurasian hemione Equus hydruntinus. While the former survived the Holocene–Pleistocene until now, the timing for the extinction of the latter is unclear. Scarce, fragmented archaeological remains assess the presence of small equids living in the Holocene of Iberia. Those could possibly correspond to the Eurasian hemione although unambiguous morphological identification is often not possible. With the find of an equid tooth from Leceia, a Chalcolithic fortified site in Portugal, and using both morphological and mitochondrial genome analyses, we demonstrate for the first time the presence of a new equid species in Holocene Iberia, namely a donkey (Equus asinus). Radiocarbon dating of the tooth to Cal 2340–2130, and 2080–2060 BC with 95% probability, demonstrates that donkeys were present in Iberia well before the arrival of Phoenicians in the first quarter of the first millennium BC (900–750 years BC), which were considered so far as the first who introduced donkeys in the region.  相似文献   
105.
In this paper, the infrared stimulated luminescence (IRSL) property of naturally corroded aluminum and its possible applications in retrospective dosimetry have been briefly studied. Results are interesting, in particular with regard to the efforts of finding new and widely available materials for accident dosimetry. For aluminum corrosion, the dose response was found to be approximately linear between 2–80 Gy and to reach saturation before 300 Gy. The signal also showed good repro-ducibility without significant fading over storage durations of up to four mounts at room temperature. In addition to the luminescence, the corrosion samples were also analysed by X-ray Fluorescence (XRF) and X-ray Diffraction (XRD), but conclusive identification of the luminescent phase could not be made. It is concluded that the IRSL signals of this material can be favourable for dosimetry research.  相似文献   
106.
107.
This article describes the dynamical behavior of free-standing block structures under seismic loading. A comprehensive experimental investigation has been carried out to study the rocking response of four single blocks of different geometry and associations of two and three blocks. The blocks, which are large stones of high strength blue granite, were subjected to free vibration, and harmonic and random motions of the base. In total, 379 tests on a shaking table were carried out in order to address the issues of repeatability of the results and stability of the rocking motion response. Significant understanding of the rocking motion mechanism is possible from the high quality experimental data. Extensive experimental measurements allowed to discuss the impulsive forces acting in the blocks and the three-dimensional effects presented in the response.  相似文献   
108.
Performance-based earthquake engineering methodologies often require a probabilistic model of structural demand. Since observations masking the probability distribution of the majority of the data are frequently found, robust estimation methods are proposed to estimate the probabilistic model parameters (i.e., central value and dispersion). The performance of thirty-three robust dispersion estimators is evaluated, for different sample sizes, using the chord rotation, curvature, shear force, and inter-story drift demands obtained after analyzing five reinforced concrete structures under real earthquake records scaled to several intensities. Based on the results, combinations involving dispersion and central value (defined in a companion article) estimators are proposed.  相似文献   
109.
110.
This article investigates consumers’ perceptions of three types of sponsors that play a role in backing financially Canadian artistic and cultural organisations: government ministries (or departments), Crown corporations and private companies. In addition to the type of sponsor and the nature of the sponsorship (philanthropic or commercial), the perceived congruence between the sponsor and the sponsored event (strong as opposed to weak), and the form of arts and cultural events (high art versus popular art and performing arts versus heritage arts) are explored in an experimental setting combining within‐subjects and between‐subjects factors. The main hypothesis of this research was that consumers’ perceptions are not the same when it comes to the different kinds of sponsors that evolve in the cultural and art fields. As the researchers explored this issue, they observed that significant differences do exist. It is believed that the rich findings of this study will be useful to civil servants.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号