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91.
Josefina Carlorosi Susana Heredia Guillermo Aceñolaza 《Alcheringa: An Australasian Journal of Paleontology》2013,37(3):299-311
Carlorosi, J., Heredia, S. & Aceñolaza, G, 2013. Middle Ordovician (early Dapingian) conodonts in the Central Andean Basin of NW Argentina. Alcheringa 37, 1–13. ISSN 0311-5518. This paper describes and analyzes the significance of a conodont fauna from the Alto del Cóndor Formation, exposed in the Los Colorados region of the Argentine Eastern Cordillera. Identified taxa are Baltoniodus triangularis, Baltoniodus sp. cf. B. triangularis, Drepanodus sp., Drepanoistodus basiovalis, Drepanoistodus sp. B., Erraticodon patu, Gothodus costulatus, Oistodus sp., Trapezognathus diprion, T. quadrangulum, Triangulodus sp. and Triangulodus? sp. The presence of Baltoniodus triangularis indicates the base of the Dapingian stage (Middle Ordovician). In addition, we report the coexistence of T. diprion and T. quadrangulum. The conodont association suggests a faunal affinity with Baltica and South China, both belonging to the Shallow-Sea Realm of the Temperate-Cold Domain. Josefina Carlorosi [josefinacarlorosi77@gmail]com], INSUGEO—Universidad Nacional de Tucumán—CONICET, Miguel Lillo 205, (4000) Tucumán, Argentina; Guillermo F. Aceñolaza [acecha@webmail.unt.edu.ar], Universidad Nacional de Tucumán—CONICET, Miguel Lillo 205, (4000) Tucumán, Argentina; Susana Heredia [sheredia@unsj.edu.ar], CONICET–CIGEOBIO and Instituto de Investigaciones Mineras, Facultad de Ingeniería, Universidad Nacional de San Juan, Urquiza y Libertador, (5400) San Juan, Argentina. Received 22.8.2012; revised 18.10.2012; accepted 24.10.12. 相似文献
92.
Arturo César Taboada Arthur J. Mory Guang-Rong Shi David W. Haig María Karina Pinilla 《Alcheringa: An Australasian Journal of Paleontology》2013,37(2):207-223
Taboada, A.C., Mory, A.J., Shi, G.R., Haig, D.W. & Pinilla, M.K., 12.11.2014. An Early Permian brachiopod–gastropod fauna from the Calytrix Formation, Barbwire Terrace, Canning Basin, Western Australia. Alcheringa 39, xxx–xxx. ISSN 0311-5518A small brachiopod–gastropod fauna from a core close to the base of the Calytrix Formation within the Grant Group includes the brachiopods Altiplecus decipiens (Hosking), Myodelthyrium dickinsi (Thomas), Brachythyrinella narsarhensis (Reed), Neochonetes (Sommeriella) obrieni Archbold, Tivertonia barbwirensis sp. nov. and the gastropod Peruvispira canningensis sp. nov. The fauna has affinities with that of the late Sakmarian?early Artinskian Nura Nura Member directly overlying the Grant Group in other parts of the basin but, as with all lower Cisuralian (and Pennsylvanian) glacial strata in Western Australia, its precise age remains poorly constrained, especially in terms of correlation to international stages. Although the Calytrix fauna lies within the Pseudoreticulatispora confluens Palynozone, the only real constraint on its age (and that of the associated glacially influenced strata) is from Sakmarian (Sterlitamakian) and stratigraphically younger faunas. A brief review of radiometric ages from correlative strata elsewhere in Gondwana shows that those ages need to be updated. The presence of Asselian strata and the position of the Carboniferous?Permian boundary remain unclear in Western Australia.Arturo César Taboada [ataboada@unpata. edu. ar], CONICET-Laboratorio de Investigaciones en Evolución y Biodiversidad (LIEB), Facultad de Ciencias Naturales, Sede Esquel, Universidad Nacional de la Patagonia ‘San Juan Bosco’, Edificio de Aulas, Ruta Nacional 259, km. 16,5, Esquel U9200, Chubut, Argentina; Arthur Mory [arthur. mory@dmp. wa. gov. au], Geological Survey of Western Australia, 100 Plain Street, East Perth, WA 6004, School of Earth and Environment, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia; Guang R. Shi [grshi@deakin. edu. au], School of Life and Environmental Sciences, Deakin University, Melbourne Burwood Campus, 221 Burwood Highway, Burwood, Victoria 3125, Australia; David W. Haig [david. haig@uwa. edu. au], School of Earth and Environment (M004), The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia; María Karina Pinilla [mkpinilla@fcnym. unlp. edu. ar], División Paleozoología Invertebrados, Museo de Ciencias Naturales de La Plata, Paseo del Bosque s/n, 1900 La Plata, Buenos Aires, Argentina. 相似文献
93.
María Jimena Franco Mariana Brea Ana María Zavattieri 《Alcheringa: An Australasian Journal of Paleontology》2013,37(1):8-23
The first Miocene records of silicified fossil woods from the Mariño Formation, Potrerillos area, Andes Precordillera, Mendoza province, Argentina are described. Rhaphithamnoxylon artabeae gen. et sp. nov. is described as the first fossil wood referable to Verbenaceae from Argentina. This new fossil species is related to extant Rhaphithamnus Miers, sharing the following anatomical features: diffuse porosity, distinct growth ring boundaries, numerous small to very small vessels, commonly in radial multiples, 1–3 seriate rays, and heterocellular and scarce paratracheal axial parenchyma. Rhaphithamnus contains only two extant species: R. spinosus (A.L. Juss.) Moldenke, which occurs in the Valdivian forests of Chile and Argentina, and R. venustus (Philippi) Robinson, which is endemic to the Juan Fernández Islands. Representatives of Verbenaceae are distributed predominantly in the Americas from Patagonia (Argentina) to Canada, and they are inferred to have originated in South America. The fossil wood described herein provides new age and geographical constraints on the raphithanoid lineage within Verbenaceae. Other fossil woods recorded from the Mariño level are retained under open nomenclature, as they possess a combination of mostly solitary broad vessels, and smaller vessels in radial multiples or in clusters, with numerous, vasicentric to confluent axial parenchyma, and heterocellular, high rays. Thus, they have features akin to dicotyledonous lianas or vine-like or small shrub species. 相似文献
94.
M. Lucía Balarino 《Alcheringa: An Australasian Journal of Paleontology》2013,37(3):317-337
The first palynozonation for Permian strata of the Claromecó Basin (Argentina) is formally proposed, based on palynological assemblages recovered from the UTAL.CMM1 La Estrella.x-1 and UTAL.CMM1 Cruz de Sur.x-1 boreholes, drilled on the Argentinian Continental Platform and correlation with established zones from neighbouring basins. Fifty-five samples were analyzed and 131 species identified from two biozones. The lower Converrucosisporites confluens–Vittatina vittifera (CV) Zone occurs in the Piedra Azul and Bonete formations of both boreholes. This zone can be assigned a Cisuralian–Guadalupian age. The upper Tornopollenites toreutos–Reduviasporonites chalastus (TC) Zone registered in the Tunas Formation can be assigned a Guadalupian–Lopingian age. The CV Zone is dominated by diverse non-taeniate bisaccate, plicate and taeniate pollen. Monosaccate and monosulcate pollen, algae and acritarchs are poorly represented in both biozones. The composition of the TC Zone is broadly similar to the CV Zone, but bisaccate pollen grains are markedly more diverse and abundant in the former. 相似文献
95.
Adriana María Albino 《Alcheringa: An Australasian Journal of Paleontology》2013,37(3):412-421
Squamata are known from South America since the Cretaceous, but their fossil record has an occurrence gap between the late Eocene and early Miocene. Fossils recovered from the Sarmiento Formation (Deseadan South American Land Mammal Age, late Oligocene) at Cabeza Blanca (45°S) partially fill this interval. The squamates recovered from Cabeza Blanca include both lizards (an indeterminate Iguanidae and a probable Iguaninae) and snakes (Madtsoiidae). If these taxonomic assignments are correct, the presence of an Iguaninae at such a latitude is unexpected because these lizards are presently absent from Argentine territory. The madtsoiid, here referred to Madtsoia, would extend the Cenozoic record of this genus back to around 16?Ma. The squamate fauna from Cabeza Blanca is compatible with warm and humid environments inferred for the Patagonian Deseadan. 相似文献
96.
Enrique Suárez-Iñiguez 《Perspectives on Political Science》2013,42(1):31-35
Abstract Through a critical consideration of recent proposals urging the use of “citizen forums” or “mini-publics” on issues involving science, this article reflects on the challenge posed to democracy and democratic decision making by the intellectual authority of modern science. Though the danger of a descent into technocracy is real and pressing, arguably the most serious challenge to democracy today, these novel “deliberative democratic” institutions are unpromising as a corrective beyond the local level, and may actually exacerbate the problem. The article concludes with a consideration of alternatives. 相似文献
97.
A solid‐phase, non‐chemical processing protocol was recently developed as a means of chemically characterizing archaeological ceramics by total reflection X‐ray fluorescence (TXRF). Following this methodology, TXRF can provide semi‐quantitative determinations for 18 elements with comparable levels of precision and accuracy for the majority of them in comparison with a clay reference material analysed by instrumental neutron activation (INAA). In order critically to assess the analytical capabilities of TXRF, a large sample set of Late Iron Age Spanish Celtiberian ceramics and modern clays was analysed both by TXRF and INAA. Semi‐quantitative chemical data provided by TXRF and quantitative data provided by INAA were subjected to commonly used multivariate statistical methods as a way of evaluating the ability of the new technique to discriminate among different compositional groups. The comparison of the two data sets shows no significant discrepancies, thereby allowing support for the same archaeological interpretation. These results suggest that TXRF has potential applicability for compositional characterization of archaeological ceramics, providing data that are useful for provenance studies. 相似文献
98.
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100.
Lauren Cadwallader David G. Beresford-Jones Fraser C. Sturt Alexander G. Pullen Susana Arce Torres 《Journal of Field Archaeology》2018,43(4):316-331
This paper presents new information from funerary contexts in the lower Ica Valley, on the south coast of Peru, spanning two millennia from the end of the Early Horizon to the Late Intermediate Period. Although severely looted, these sites can still yield valuable information. We discuss their architecture and material culture in the context of radiocarbon dates. Among other findings, these cast new light on the poorly understood transition from the Middle Horizon to the Late Intermediate Period, for which a paucity of archaeological data from ca. a.d. 1000–1250 has long been taken as evidence of an environmentally- or socially-induced demographic collapse. Yet the data we present here suggest that the basins of the lower Ica Valley were likely occupied continuously over this period, and that the echoes of Wari influence here may have lasted longer than previously thought. 相似文献