全文获取类型
收费全文 | 4147篇 |
免费 | 193篇 |
出版年
2020年 | 66篇 |
2019年 | 84篇 |
2018年 | 119篇 |
2017年 | 105篇 |
2016年 | 132篇 |
2015年 | 93篇 |
2014年 | 95篇 |
2013年 | 1163篇 |
2012年 | 119篇 |
2011年 | 131篇 |
2010年 | 124篇 |
2009年 | 113篇 |
2008年 | 121篇 |
2007年 | 98篇 |
2006年 | 87篇 |
2005年 | 64篇 |
2004年 | 45篇 |
2003年 | 58篇 |
2002年 | 49篇 |
2001年 | 74篇 |
2000年 | 57篇 |
1999年 | 61篇 |
1998年 | 53篇 |
1997年 | 36篇 |
1996年 | 39篇 |
1995年 | 48篇 |
1994年 | 44篇 |
1993年 | 37篇 |
1992年 | 42篇 |
1991年 | 35篇 |
1990年 | 35篇 |
1989年 | 30篇 |
1988年 | 39篇 |
1987年 | 47篇 |
1986年 | 36篇 |
1985年 | 48篇 |
1984年 | 48篇 |
1983年 | 50篇 |
1982年 | 51篇 |
1981年 | 46篇 |
1980年 | 39篇 |
1979年 | 33篇 |
1978年 | 37篇 |
1977年 | 41篇 |
1976年 | 32篇 |
1974年 | 37篇 |
1973年 | 21篇 |
1971年 | 22篇 |
1970年 | 24篇 |
1969年 | 20篇 |
排序方式: 共有4340条查询结果,搜索用时 15 毫秒
971.
972.
ROBERT J. C. MOWAT 《International Journal of Nautical Archaeology》2019,48(2):528-529
973.
974.
975.
New Insights into the Provenance of the Obsidian Fragments of the Island of Ustica (Palermo,Sicily) 下载免费PDF全文
F. Foresta Martin A. Di Piazza C. D'Oriano M. L. Carapezza A. Paonita S. G. Rotolo L. Sagnotti 《Archaeometry》2017,59(3):435-454
In this study we applied a multidisciplinary approach, coupling geophysical and geochemical measurements, to unveil the provenance of 170 obsidian flakes, collected on the volcanic island of Ustica (Sicily). On this island there are some prehistoric settlements dated from the Neolithic to the Middle Bronze Age. Despite not having geological outcrops of obsidian rocks, the countryside of Ustica is rich in fragments of this volcanic glass, imported from other source areas. The study of obsidian findings was carried out first through visual observations and density measurements. At least two different obsidian families have been distinguished, probably imported from Lipari and Pantelleria islands. Analysing the magnetic properties of the samples, these two main sources were confirmed, but the possibility of other provenances was inferred. Finally, we characterized the geochemical signature of the Ustica obsidians by performing microchemical analyses through electron microprobe (EMPA) and laser ablation (LA–ICP–MS). The results were compared with literature data, confirming the presence of the Lipari and Pantelleria sources (Sicily) and indicating for the first time in this part of Italy a third provenance from Palmarola island (Latium). Our results shed new light on the commercial exchanges in the peri‐Tyrrhenian area during the prehistoric age. 相似文献
976.
Lead Isotope Analyses Revealed the Key Role of Chang'an in the Mirror Production and Distribution Network During the Han Dynasty 总被引:1,自引:0,他引:1 下载免费PDF全文
Y. Z. Zhangsun R. L. Liu Z. Y. Jin A. M. Pollard X. Lu P. J. Bray A. C. Fan F. Huang 《Archaeometry》2017,59(4):685-713
Chang'an (now Xi'an) was the capital of the Western Han Dynasty and the starting point of the Silk Road. In the light of the importance of Chang'an as the centre of politics, economy and cultural interaction, the overarching question proposed in this paper is focused on its role in the mirror production and distribution network during Han period. On the basis of chemical and lead isotopic analyses of 34 Han mirrors, this paper discusses the potential existence of a mirror production centre in Chang'an. Meanwhile, a comparative study with mirrors uncovered from the south‐western frontier and from Central Asian and North‐East Asian countries offers new insight into these related issues. 相似文献
977.
Integrated Analytical Techniques for the Study of Colouring Materials from Two Megalithic Barrows 下载免费PDF全文
C. Oliveira A. M. S. Bettencourt A. Araújo L. Gonçalves I. Kuźniarska‐Biernacka A. L. Costa 《Archaeometry》2017,59(6):1065-1081
We have determined the composition of rock art pigments from two megalithic barrows located in the north of Portugal. The use of XRD, SEM–EDS and FT–IR spectroscopy confirmed the presence of hematite and kaolinite in the red pigments from the Eireira barrow, and kaolinite in the white pigment from the Leira das Mamas barrow. The organic composition of the pigments was studied by GC–MS, suggesting that the red sinuous lines and dots from the Eireira barrow were prepared with cooked or heated algae and/or aquatic plants, with egg as binder, while the white pigment from the Leira das Mamas barrow revealed a mixture of vegetable oils for kaolinite moulding, which could be stabilized by temporary exposure to high temperatures. The multi‐analytical approach used on this study of megalithic pigments allowed the recovery of important data about north‐western prehistoric communities, namely the way in which they exploited existing resources and their ability to transform them. 相似文献
978.
Was He Murdered or Was He Not?—Part II: Multi‐Elemental Analyses of Hair and Bone Samples from Tycho Brahe and Histopathology of His Bones 下载免费PDF全文
J. Kučera K. L. Rasmussen J. Kameník M. Kubešová L. Skytte C. Povýšil V. Karpenko V. Havránek P. Velemínský N. Lynnerup J. Brůžek J. Smolík J. Vellev 《Archaeometry》2017,59(5):918-933
Hair and bone samples procured from the remains of Tycho Brahe were analysed by several analytical techniques. In segmented hair samples, concentrations of Fe, As, Ag and Au at the tips exceeded values for the contemporary population; however, they decreased towards the hair bulbs, similarly to Hg, indicating that recent exposure that was discontinued ~2 months prior to Brahe's death. Several other elements did not follow this pattern. Analyses of bones revealed signs of long‐term exposure to Au, while many other elements were within expected ranges. Histopathological examination of bone sections yielded no signs of severe bone metabolic disorders. 相似文献
979.
Magnetic Alteration of Soils by Late Holocene Hunter–Gatherer Groups (Tierra Del Fuego,South America) 下载免费PDF全文
The present work aims to analyse the magnetic signature from the Late Holocene open‐air archaeological deposits of hunter–gatherer ephemeral occupations. For this purpose, two profiles were sampled at the Marazzi 2 site in the north‐western Isla Grande de Tierra del Fuego, Chile, in order to carry out studies of magnetic susceptibility, hysteresis cycles, back‐field remanent magnetization, isothermal remanent magnetization and thermal variation of magnetic susceptibility at high and low temperature. Despite short‐term occupations, the P1 profile shows a magnetic peak at a depth of ~30–70 cm due to magnetite, probably formed by anthropogenic activity related to combustion. The P2 profile instead yields an anomalous peak of coercivity (at a depth of 20–40 cm), which could also be anthropogenic, due to the presence of finely dispersed ancient ‘red ochre’. The red ochre is proposed to form anthropogenic thermal alteration of goethite associated with volcanic ash, the remnants of which were found in thin sections from the P2 subsoil. 相似文献
980.
Gnai Nishani Musafer Mery Helen Thompson Rodney C. Wolff Erhan Kozan 《Geographical analysis》2017,49(4):409-432
A novel geostatistical modeling approach is developed to model nonlinear multivariate spatial dependence using nonlinear principal component analysis (NLPCA) and pair‐copulas. In spatial studies, multivariate measurements are frequently collected at each location. The dependence between such measurements can be complex. In this article, a multivariate geostatistical model is developed that can capture both nonlinear spatial dependence across locations and nonlinear dependence between measurements at a particular location. Nonlinear multivariate dependence between spatial variables is removed using NLPCA. Subsequently, a pair‐copula based model is fitted to each transformed variable to model the univariate nonlinear spatial dependencies. NLPCA and pair‐copulas, within the proposed model, are compared with stepwise conditional transformation (SCT) and conventional kriging. The results show that, for the two case studies presented, the proposed model that utilizes NLPCA and pair‐copulas reproduces nonlinear multivariate structures and univariate distributions better than existing methods based on SCT and kriging. 相似文献