全文获取类型
收费全文 | 445篇 |
免费 | 22篇 |
专业分类
467篇 |
出版年
2021年 | 2篇 |
2020年 | 7篇 |
2019年 | 15篇 |
2018年 | 15篇 |
2017年 | 15篇 |
2016年 | 25篇 |
2015年 | 14篇 |
2014年 | 11篇 |
2013年 | 134篇 |
2012年 | 17篇 |
2011年 | 13篇 |
2010年 | 8篇 |
2009年 | 16篇 |
2008年 | 6篇 |
2007年 | 7篇 |
2006年 | 8篇 |
2005年 | 4篇 |
2004年 | 10篇 |
2003年 | 6篇 |
2002年 | 8篇 |
2001年 | 2篇 |
2000年 | 5篇 |
1999年 | 5篇 |
1998年 | 6篇 |
1997年 | 5篇 |
1995年 | 7篇 |
1994年 | 4篇 |
1993年 | 3篇 |
1991年 | 5篇 |
1990年 | 2篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1986年 | 3篇 |
1985年 | 6篇 |
1984年 | 8篇 |
1983年 | 5篇 |
1982年 | 6篇 |
1981年 | 4篇 |
1980年 | 7篇 |
1979年 | 4篇 |
1978年 | 5篇 |
1977年 | 3篇 |
1976年 | 5篇 |
1975年 | 4篇 |
1974年 | 1篇 |
1973年 | 3篇 |
1972年 | 2篇 |
1971年 | 2篇 |
1970年 | 1篇 |
1969年 | 4篇 |
排序方式: 共有467条查询结果,搜索用时 15 毫秒
51.
52.
Stephen F. Poropat Jay P. Nair Caitlin E. Syme Philip D. Mannion Paul Upchurch Scott A. Hocknull 《Alcheringa: An Australasian Journal of Paleontology》2017,41(4):543-580
Poropat, S.F., Nair, J.P., Syme, C.E., Mannion, P.D., Upchurch, P., Hocknull, S.A., Cook, A.G., Tischler, T.R. &; Holland, T. XX.XXXX. 2017. Reappraisal of Austrosaurus mckillopi Longman, 1933 from the Allaru Mudstone of Queensland, Australia’s first named Cretaceous sauropod dinosaur. Alcheringa 41, 543–580. ISSN 0311-5518Austrosaurus mckillopi was the first Cretaceous sauropod reported from Australia, and the first Cretaceous dinosaur reported from Queensland (northeast Australia). This sauropod taxon was established on the basis of several fragmentary presacral vertebrae (QM F2316) derived from the uppermost Lower Cretaceous (upper Albian) Allaru Mudstone, at a locality situated 77 km west-northwest of Richmond, Queensland. Prior to its rediscovery in 2014, the type site was considered lost after failed attempts to relocate it in the 1970s. Excavations at the site in 2014 and 2015 led to the recovery of several partial dorsal ribs and fragments of presacral vertebrae, all of which clearly pertained to a single sauropod dinosaur. The discovery of new material of the type individual of Austrosaurus mckillopi, in tandem with a reassessment of the material collected in the 1930s, has facilitated the rearticulation of the specimen. The resultant vertebral series comprises six presacral vertebrae—the posteriormost cervical and five anteriormost dorsals—in association with five left dorsal ribs and one right one. The fragmentary nature of the type specimen has historically hindered assessments of the phylogenetic affinities of Austrosaurus, as has the fact that these evaluations were often based on a subset of the type material. The reappraisal of the type series of Austrosaurus presented herein, on the basis of both external morphology and internal morphology visualized through CT data, validates it as a diagnostic titanosauriform taxon, tentatively placed in Somphospondyli, and characterized by the possession of an accessory lateral pneumatic foramen on dorsal vertebra I (a feature that appears to be autapomorphic) and by the presence of a robust ventral mid-line ridge on the centra of dorsal vertebrae I and II. The interpretation of the anteriormost preserved vertebra in Austrosaurus as a posterior cervical has also prompted the re-evaluation of an isolated, partial, posterior cervical vertebra (QM F6142, the ‘Hughenden sauropod’) from the upper Albian Toolebuc Formation (which underlies the Allaru Mudstone). Although this vertebra preserves an apparent unique character of its own (a spinopostzygapophyseal lamina fossa), it is not able to be referred unequivocally to Austrosaurus and is retained as Titanosauriformes indet. Austrosaurus mckillopi is one of the oldest known sauropods from the Australian Cretaceous based on skeletal remains and potentially provides phylogenetic and/or palaeobiogeographic context for later taxa such as Wintonotitan wattsi, Diamantinasaurus matildae and Savannasaurus elliottorum.Stephen F. Poropat* [sporopat@swin. edu. au; stephenfporopat@gmail. com] Department of Chemistry and Biotechnology, Swinburne University of Technology, John St, Hawthorn, Victoria 3122, Australia; Jay P. Nair [j. nair@uq. edu. au; jayraptor@gmail. com] School of Biological Sciences, The University of Queensland, St Lucia, Queensland 4072, Australia; Caitlin E. Syme [caitlin. syme@uqconnect. edu. au] School of Biological Sciences, The University of Queensland, St Lucia, Queensland 4072, Australia; Philip D. Mannion [philipdmannion@gmail. com] Department of Earth Science and Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ, UK; Paul Upchurch [p. upchurch@ucl. ac. uk] Department of Earth Sciences, University College London, Gower Street, London WC1E 6BT, UK; Scott A. Hocknull [scott. hocknull@qm. qld. gov. au] Geosciences, Queensland Museum, 122 Gerler Rd, Hendra, Queensland 4011, Australia; Alex G. Cook [alex. cook@y7mail. com] School of Earth Sciences, The University of Queensland, St Lucia, Queensland 4072, Australia; Travis R. Tischler [travisr. tischler@outlook. com] Australian Age of Dinosaurs Museum of Natural History, Lot 1 Dinosaur Drive, PO Box 408, Winton, Queensland 4735, Australia; Timothy Holland [drtimothyholland@gmail. com] Kronosaurus Korner, 91 Goldring St, Richmond, Queensland 4822, Australia. *Also affiliated with: Australian Age of Dinosaurs Museum of Natural History, Lot 1 Dinosaur Drive, PO Box 408, Winton, Queensland 4735, Australia. 相似文献
53.
54.
55.
56.
57.
58.
59.
The coverage provided by the existing solar radiation monitoring network for British Columbia and adjacent areas in western Canada is assessed and found to be inadequate. It is generally advantageous to use a numerical solar radiation model at available sites to augment the observed values, although this is not a complete solution to the problem. It is also shown that the ability to extrapolate solar radiation data from measurement and modelling locations is strongly determined by the general nature of the synoptic weather conditions. In addition, the use of solar radiation extrapolations is restricted by problems involving homogeneity and isotropy assumptions.
Les auteurs presentent une evaluation de la distribution des stations en Colombie britannique et les aires adjacents du Canada de I'ouest mesurant la radiation solaire; ils en concluent que le reseau actuel est inadequat. 11s soulignent I'avantage d'emprunter un modele numerique pour caracteriser la radiation solaire aux sites disponibles, afin d'aug-menter les donnees observees. Neanmoins, cela ne represente pas pour les auteurs une solution complete du probleme. 11s demontrent que le caractere general des conditions meteorologiques synoptiques determine fortement la possibilite d'une extrapolation de la distribution de la radiation solaire, derivee des donnees mesurees et des modeles adoptes aux sites specifiques. Finalement, ils etablissent que certains problemes concernant les hypo-theses d'homogeneite et d'isotropie imposent leur tour des limites a I'utilite de la methoded'extrapolation pour decrire la radiation solaire. 相似文献
Les auteurs presentent une evaluation de la distribution des stations en Colombie britannique et les aires adjacents du Canada de I'ouest mesurant la radiation solaire; ils en concluent que le reseau actuel est inadequat. 11s soulignent I'avantage d'emprunter un modele numerique pour caracteriser la radiation solaire aux sites disponibles, afin d'aug-menter les donnees observees. Neanmoins, cela ne represente pas pour les auteurs une solution complete du probleme. 11s demontrent que le caractere general des conditions meteorologiques synoptiques determine fortement la possibilite d'une extrapolation de la distribution de la radiation solaire, derivee des donnees mesurees et des modeles adoptes aux sites specifiques. Finalement, ils etablissent que certains problemes concernant les hypo-theses d'homogeneite et d'isotropie imposent leur tour des limites a I'utilite de la methoded'extrapolation pour decrire la radiation solaire. 相似文献
60.