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241.
Jeffrey D. Stilwell Jesse J. Vitacca Chris Mays 《Alcheringa: An Australasian Journal of Paleontology》2016,40(4):502-508
Stilwell, J.D., Vitacca, J. & Mays, C., April 2016. South polar greenhouse insects (Arthropoda: Insecta: Coleoptera) from the mid-Cretaceous Tupuangi Formation, Chatham Islands, eastern Zealandia. Alcheringa 40, xxx–xxx. ISSN 0311-5518Rare insect body fossils have been discovered for the first time after 175 years of research on the Chatham Islands, eastern ‘Zealandia’. The coleopteran (beetle) insects, dated to ca 95 Ma and extracted from fine-grained, upper delta plain facies in the lower Upper Cretaceous (Cenomanian–lowermost Turonian) Tupuangi Formation at Waihere Bay on the remote Pitt Island, represent the most southern, polar-latitude (ca 70–80°S) faunal assemblage from the Cretaceous recorded to date. Three species are represented in the insect fauna: a portion of a segmented abdomen of a probable carabid? ground beetle and two distinct coleopteran elytra, one preserved with a brilliantly iridescent carapace upon discovery, comparable with Cretaceous taxa within the Buprestidae (metallic wood borers), but identification with the Chrysomelidae (leaf beetles) or Tenebrionidae (darkling beetles) can not be discounted entirely. Another specimen has more weakly preserved greenish iridescence and has a morphology consistent with Carabidae; given the preservational deficiencies and rarity of material, the specimens are attributed to Buprestidae? genus et species indeterminate and Carabidae? genus et species indeterminate A and B, respectively. These coleopteran fossils represent the only recorded iridescence in Mesozoic invertebrates from Zealandia. Importantly, these mid-Cretaceous insects existed in South Polar forests near the height of the ‘hothouse’ phase of relatively warm, alternating intervals of full daylight in the summer months and total darkness during the winter, before eastern Zealandia diverged at ca 83 Ma from the Marie Byrd Land region of West Antarctica, as part of the final break-up of Gondwana.Jeffrey D. Stilwell* [jeffrey. stilwell@monash. edu], Jesse V. Vitacca [jesse. vitacca@gmail. com] & Chris Mays [chris. mays@monash. edu], School of Earth, Atmosphere and Environment, Monash University, Clayton VIC 3800, Australia. *Also affiliated with the Australian Museum, 6 College Street, Sydney NSW 2000, Australia. 相似文献
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Chris Eipper 《Oceania; a journal devoted to the study of the native peoples of Australia, New Guinea, and the Islands of the Pacific》1983,54(1):73-75
Minangkabau Social Formations.: By Joel S. Kahn. Cambridge University Press 1980. Price £UK15.00. 相似文献
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Elise Dufour Chris Holmden Wim Van Neer Antoine Zazzo William P. Patterson Patrick Degryse Eddy Keppens 《Journal of archaeological science》2007
In this paper, we investigate the potential use of oxygen and strontium isotope ratios (δ18Op and 87Sr/86Sr) measured in archaeological fish enamel as provenance indicators. δ18Op and 87Sr/86Sr were measured in a suite of archaeological carp remains recovered from the Anatolian townsite of Sagalassos dated to the Early Byzantine period (AD 450–650) and compared to that of modern fish, river and lake waters from the Anatolian region. We used sequential leaches in weak acetic acid to remove diagenetic Sr from fossil tooth enamel, monitoring the effectiveness of this approach by measuring the Sr/Ca ratios of the leachates via an isotope dilution thermal ionization mass spectrometry method (ID-TIMS). δ18Op values mostly excluded a riverine origin. 87Sr/86Sr ratios of one fish overlapped with the 87Sr/86Sr signatures of two lakes in the Anatolian region, and at least one lake (Gölcük) could be removed as a candidate owing to a very distinctive 87Sr/86Sr signature not found in any of the fish remains. Most of the tooth samples analyzed could not be assigned a precise geographical origin since the 87Sr/86Sr ratios measured in enamel did not match that of any of the local lakes selected as potential origin. This result suggests that carp may have originated from lakes that have not yet been sampled, although this conclusion is not supported by other archaeological evidence. Alternatively, the lack of correspondence between lakes and fish Sr isotope ratios highlights several possible sources of uncertainties including spatial heterogeneity in 87Sr/86Sr ratio within a lake, the contribution of dietary strontium to the 87Sr/86Sr ratio of fish tooth enamel, and post-mortem alteration of the tooth Sr isotope signal during fossilization. In spite of the high precision of the strontium isotope analyses and the wide range of variation in the surface waters of the Anatolian lakes and rivers, this method may remain limited to distinguishing between lakes situated in regions of bedrock of very distinct age and geology until these sources of uncertainty are more fully investigated. 相似文献
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This article examines the role of the institutional power of executives in public budgeting; specifically, how executives change spending on particular budget items. Leveraging extant theories of the policy process concerning preference expression, attention, and institutions, we argue that executives deepen large cuts and boost large increases in budgetary change. The strictures of the budgetary process force trade-offs for executives in preference expression such that increases to preferred categories typically require decreases in other categories. Literatures in public policy and political representation suggest that all executives would like to express fiscal preferences, thereby contributing to categorical budget oscillations; however, not all executives are created equal. We employ quantile regression to examine whether the institutional strength of governors determine cuts, stasis, and expansion in spending across all budget functions in the American states between 1985 and 2009. Our model includes a host of political and economic variables found in the literature of fiscal policymaking, such as partisanship and divided government. The desire to change policy may be widely shared across executives, but we find that the ability to “top off” categorical increases and bottom out categorical decreases is a function of an executive's capacity to call attention to preferred categories via agenda-setting power and to secure those changes via veto power. The findings show strong governors are well positioned to influence public policy through the budgetary process. 相似文献