全文获取类型
收费全文 | 289篇 |
免费 | 23篇 |
出版年
2023年 | 1篇 |
2021年 | 5篇 |
2020年 | 5篇 |
2019年 | 10篇 |
2018年 | 13篇 |
2017年 | 22篇 |
2016年 | 16篇 |
2015年 | 9篇 |
2014年 | 11篇 |
2013年 | 79篇 |
2012年 | 9篇 |
2011年 | 14篇 |
2010年 | 12篇 |
2009年 | 7篇 |
2008年 | 8篇 |
2007年 | 8篇 |
2006年 | 9篇 |
2005年 | 3篇 |
2004年 | 3篇 |
2003年 | 4篇 |
2002年 | 4篇 |
2001年 | 3篇 |
2000年 | 1篇 |
1999年 | 8篇 |
1998年 | 4篇 |
1997年 | 2篇 |
1996年 | 3篇 |
1995年 | 6篇 |
1994年 | 4篇 |
1993年 | 3篇 |
1991年 | 2篇 |
1989年 | 3篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 3篇 |
1984年 | 5篇 |
1983年 | 3篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1975年 | 2篇 |
排序方式: 共有312条查询结果,搜索用时 15 毫秒
251.
Timothy L. M. Sharp 《Oceania; a journal devoted to the study of the native peoples of Australia, New Guinea, and the Islands of the Pacific》2019,89(2):182-204
The rise of competitive trade practices represents a significant development in Papua New Guinea's marketplaces. Overt competition and haggling, once conspicuous by their near absence, are now commonplace in the country's betel nut marketplaces, and increasingly visible in many of the large urban fresh food marketplaces. This has emerged with the rise of long‐distance and intermediary trading, and with increasing numbers of people dependent on trade for their livelihood. This paper explores moral economy, and the interactions and negotiations around price between lowland betel nut producers and highland wholesale traders as they occur in marketplaces and in rural production areas. It documents how the moral obligations that arise from trade itself, and entangled with self‐interest, tempers competition and fosters solidarity amongst traders, redirects competition onto their interactions with producers, and in doing so reinforces existing power asymmetries. 相似文献
252.
253.
Timothy P. Topper 《Alcheringa: An Australasian Journal of Paleontology》2013,37(3):427-443
A small assemblage of isolated Microdictyon plates is described from the lower Cambrian Ajax Limestone, Mt Scott Range (Flinders Ranges), South Australia. Microdictyon plates are primarily known from single, isolated, perforated phosphatic sclerites; only one species (M. sinicum) from the Chengjiang Lagerstätte is known from soft-bodied preservation of the complete organism. The isolated plates from South Australia display a wide range of morphologies potentially reflecting: 1, considerable diversification within the group at this time; 2, extensive intraspecific morphological variation; 3, different plate morphotypes along the trunk of the animal; or 4, significant ontogenetic variation in successive growth stages. The South Australian specimens are similar to several individual sclerites described from other Cambrian palaeocontinents, but appear closest to faunas described from South China. Problems associated with the taxonomy of isolated Microdictyon plates are discussed, including the lack of knowledge associated with intraspecific and/or ontogenetic variability and how individual plate morphology may relate to size or relative position along the length of the complete organism. 相似文献
254.
Kristian G. Jakobsen Glenn A. Brock Arne T. Nielsen Timothy P. Topper David A.T. Harper 《Alcheringa: An Australasian Journal of Paleontology》2013,37(2):190-208
Jakobsen, K.G., Brock, G.A, Nielsen, A.T., Topper, T.P. & Harper, D.A.T., 2013. Middle Ordovician brachiopods from the Stairway Sandstone, Amadeus Basin, central Australia. Alcheringa. ISSN 0311–5518.Middle Ordovician brachiopod faunas from the Amadeus Basin, central Australia are poorly known. The Darriwilian Stairway Sandstone was sampled stratigraphically for macrofossils in order to provide new information on marine benthic diversity in this clastic-dominated, shallow-water palaeoenvironment along the margin of northeastern Gondwana. The brachiopods from the Stairway Sandstone are of low diversity and represent ca 9% of the entire shelly fauna. Five brachiopod taxa are described from the Stairway Sandstone; all are endemic to the Amadeus Basin at species level. Two new species, Amadeuphyla joanae gen. et sp. nov. and Paralenorthis luritjaorum sp. nov., are described. Unweighted cladistic analysis based on 20 characters places the new genus Amadeuphyla within the Taffinae.Kristian G. Jakobsen [kgjakobsen@snm. ku. dk] Geological Museum, Natural History Museum of Denmark, University of Copenhagen, Øster Voldgade 5–7, DK-1350 Copenhagen, Denmark & Department of Biological Sciences, Macquarie University, New South Wales 2109, Australia. Glenn A. Brock [glenn. brock@mq. edu. au] Department of Biological Sciences, Macquarie University, New South Wales 2109, Australia. Arne T. Nielsen [arnet@snm. ku. dk] Geological Museum, Natural History Museum of Denmark, University of Copenhagen, Øster Voldgade 5–7, DK-1350 Copenhagen, Denmark. Timothy P. Topper [timothy. topper@snm. ku. dk] Geological Museum, Natural History Museum of Denmark, University of Copenhagen, Øster Voldgade 5–7, DK-1350 Copenhagen, Denmark. David A. T. Harper [david. harper@durham. ac. uk] Geological Museum, Natural History Museum of Denmark, University of Copenhagen, Øster Voldgade 5–7, DK-1350 Copenhagen, Denmark & Department of Earth Sciences, Durham University, Durham, UK. Received 14.6.2013; revised 25.9.2013; accepted 8.10.2013. 相似文献
255.
Paul Bodin John Vidale Timothy Walsh Recep Çakir Mehmet Çelebi 《Journal of Earthquake Engineering》2013,17(5):607-622
The Natural Resources Building (NRB) in Olympia, Washington, was shaken by three earthquakes (Mw = 5.8, 6.8, and 5.0) between 1999 and 2001. Building motions were recorded on digital accelerographs, providing important digital recordings of repeated strong shaking in a building. The NRB has 5-stories above grade with 3 sub-grade levels and a ductile steel-frame elongated in the E-W direction. The upper two floors extend significantly beyond the lower 3 on the southern and eastern sides. N-S motions dominate the fundamental modal vibrations of the building system. In the 1999 Satsop M5.8 earthquake, the frequency of this fundamental system mode was 1.3 Hz during motions of 10% g. The frequency dropped to 0.7 Hz during the 2001 M6.8 Nisqually strong motions. Moreover, the Nisqually recordings reveal both numerous high-frequency transients of up to 0.18 g, several of which are visible on widely spaced sensors, and long-term tilts of some of the sensors. The weaker 2001 M5.0 Satsop earthquake motions showed the frequency remained depressed at less than 1 Hz for the eastern side of the structure, although the western side had recovered to 1.3 Hz. An ambient noise survey in 2008 showed the fundamental frequency of N/S vibrations remains about 1.0 Hz for the eastern side of the building and 1.3 Hz for the western side. These results suggest that in the Nisqually earthquake, the east side of the NRB suffered a permanent reduction in fundamental mode frequency of 37% due to loss of system stiffness by undetermined mechanism. 相似文献
256.
This paper analyzes institutional dynamics affecting Congress's impeachment decisions regarding the Iran-Contra Affair and the Clinton-Lewinsky scandal. While other scholars have explained the Clinton impeachment by pointing to differences in the nature of the scandals–a decoupling of public opinion from legislative action, increasing partisanship, and a new media regime–these explanations overlook the nature of impeachment as an institutional confrontation, governed by institutional choices and dynamics. Taking an institutional approach, we argue that congressional decisions were strongly affected by the institutional arrangements adopted by Congress to handle the scandals' investigations. In brief, the earlier strategic approaches of party leaders and the congressional investigatory approach restrained inclinations to impeach President Reagan, while later ones promoted President Clinton's impeachment. More broadly, this analysis demonstrates the important interaction between institutional choices and party leaders' powers and strategies in affecting congressional action. 相似文献
257.
258.
259.
260.