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151.
Jean-Baptiste Mallye Céline Thiébaut Vincent Mourre Sandrine CostamagnoÉmilie Claud Patrick Weisbecker 《Journal of archaeological science》2012,39(4):1131-1142
Retouchers are fragments of bone used during the Paleolithic to strike stone flakes in order to transform them into retouched tools. Our experiments show that the mark produced on retouchers differs depending on whether they were used to strike flint or quartzite. Our results suggest that numerous pits, most often with an ovoid form, characterize the retouching of quartzite flakes. Most of the scores produced with this material have a sinuous morphology with rough interior faces. The areas with superposed traces have a pitted appearance. On the other hand, the retouching of flint flakes, produces pits that are most often triangular in form. Most of the scores have a rectilinear morphology with smooth interior faces and their superposition results in the formation of hatch marks. There is also a relationship between the characteristics of the mark and the relative state of freshness of the retouchers. The validity of the criteria identified was confirmed by a blind test. These diagnostic criteria were applied to archaeological retouchers from the Mousterian site of Noisetier Cave. The results obtained improve our knowledge of the technical behaviors of Neanderthals and allow us to address questions concerning their techno-economic implications. 相似文献
152.
Abstract The purpose of this paper is to investigate how previous experience and location of entrepreneurs influence the survival of new tourism firms. The paper departs from recent evolutionary economic geography advancements, highlighting the importance of routines and skills as well as location-specific knowledge for firm success. While having been well-researched for manufacturing industries characterized by high entry barriers, little knowledge is currently available on the factors influencing survival rates in service sectors with low entry barriers. A quantitative approach applies hazard models to investigate the survival rates over a seven-year period of a total of 133 new micro-tourism firms started between 1999 and 2001 in the four northernmost counties of Sweden. The geo-referenced micro-database ASTRID links information on firm features (e.g. firm births and deaths, spatial coordinates and industry codes) to characteristics of entrepreneurs (e.g. age, education, previous experience). The main finding is that entrepreneurs with previous work experience in related sectors are more likely to survive and, in this case, entrepreneurs without local experience tend to be less successful. We find no evidence that new firms operating in regions specialized in tourism have a survival advantage. Our analysis also indicates that surviving firms improve performance over time. The paper thus contributes new knowledge on the determinants of micro-firm survival in tourism. 相似文献
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Patrick G. Quilty Nicola Clark Ty Hibberd 《Alcheringa: An Australasian Journal of Paleontology》2013,37(2):200-206
Quilty, P.G., Clark, N. & Hibberd, T., 21.01.2015. Crenostrea sp. cf. C. cannoni (Marwick, 1928) (Bivalvia: Ostreacea) and associated fauna from east of Heard Island, Kerguelen Plateau: age and palaeoenvironmental value. Alcheringa 39, xxx–xxx. ISSN 0311-5518A well-preserved single left valve of a large oyster embedded in coarse volcaniclastic sediment and identified as Crenostrea sp. cf. C. cannoni (Marwick, 1928) was dredged from east of Heard Island, central southern Indian Ocean. It is accompanied by a fragment of the pectinid bivalve Austrochlamys sp. indet. and foraminifera. Austrochlamys sp. indet. and other bivalve fragments were analysed for 87Sr/86Sr, δ18O and δ13C, the results yielding an age of 17.5 Ma (later early Miocene) and a water temperature of ca 10°C. Foraminifera and sediment characteristics indicate that accumulation occurred in mid-continental shelf depths, at a location where nutrient supply was good.Patrick G. Quilty [p. quilty@utas. edu. au], School of Earth Sciences (Private Bag 79) and Institute for Marine and Antarctic Studies (IMAS: Private Bag 129), University of Tasmania, Hobart, Tasmania 7001, Australia. Nicola Clark [nc118@leicester. ac. uk], Department of Geology, University of Leicester, University Road, Leicester LE1 7RH, UK. Ty Hibberd [ty. hibberd@aad. gov. au], Australian Antarctic Division, Channel Highway, Kingston, Tasmania 7050, Australia. 相似文献
156.
Patrick M. Smith Glenn A. Brock John R. Paterson 《Alcheringa: An Australasian Journal of Paleontology》2013,37(1):40-70
A new faunal assemblage is reported from the Tempe Formation (Cambrian Series 2, Stage 4; Ordian) retrieved from the Hermannsburg 41 drillcore, Amadeus Basin, central Australia. Two trilobite taxa, including one new species Gunnia fava sp. nov., four brachiopod taxa, including the age-diagnostic Karathele napuru (Kruse), Kostjubella djagoran (Kruse) and Micromitra nerranubawu Kruse, together with a bradoriid, helcionellids, hyoliths, echinoderms, chancelloriids, sponges and problematic tubes are described. The fauna has close links to those of the neighbouring Daly, Georgina and Wiso basins and suggests that the Tempe Formation correlates with the Australian Ordian stage (either the Redlichia forresti or Xystridura negrina assemblage zones). The Giles Creek Dolostone in the eastern Amadeus Basin, previously regarded as coeval with the Tempe Formation, has recently been reported to be of early Templetonian age in its type section. The described taxa from the Tempe Formation confirm that these two sedimentary units are not contemporaneous and that regional stratigraphic schemes should be amended. 相似文献
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Patrick K. O'Brien 《国际历史评论》2013,35(2):345-367
WILLIAM R. THOMPSON. The Emergence of the Global Political Economy. London and New York: Routledge, 2000. Pp. xi, 252. $25.99 (US), paper; DEREK H. ALDCROFT and ANTHONY SUTCLIFFE, eds. Europe in the International Economy, 1500–2000. Cheltenham and Northampton, Mass.: Edward Elgar Publishing, 1999. Pp. xi, 289. $90.00 (US); KENNETH POMERANZ. The Great Divergence: Europe, China, and the Making of the Modern World Economy. Princeton: Princeton University Press, 2000. Pp. x, 382. $39.95 (US). 相似文献
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