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161.
This paper provides the results of the dendrochronological analyses of seven wood samples from the Ottoman fortress of Seddülbahir on the Gallipoli Peninsula or Turkey. It concludes that the trees were cut in the late spring of 1656. The data collected allows the first building phase of the fortress to be securely dated. By bringing together the dendrochronological results with various archival records about the fortress, a more precise building chronology for the fortress can be reconstructed. The probable initial period of construction was between 1656 and 1661.  相似文献   
162.
The Laibin hominid represents one of the rare finds of modern Homo sapiens in China, rare for its relative completeness and well-established stratigaphic provenance. This paper presents the results of mass spectrometric U-series dating of intercalated calcite samples from the Laibin site. The capping flowstone and the calcite vein, which sandwich the hominid fossil-containing deposits, date to 38.5 ± 1.0 and 44.0 ± 0.8 ka, setting respectively the minimum and maximum ages to the fossils. The second flowstone layer is 112.0 ± 1.4 ka old, indicating that the cultural sequence may possibly extend to somewhere between 44 and 112 ka. Securely dated Laibin finds should be of importance in reconstructing human physical and cultural evolution in the region.  相似文献   
163.
Among the dating methods in archaeology, thermoluminescence (TL) is widely developed. The present research concerns the construction chronology of the citadel of Termez (Uzbekistan) in the medieval period. On the methodological side along the TL study, we had to take into account two decisive factors that are expected to affect the accuracy: control of anomalous fading on the polymineral fraction (quartz and feldspars) and the effect of thermal treatments on the luminescence properties of the dated material. With regard to the determination of the annual dose, difficulties, associated with the evolution of the radiochemical composition of the dated samples and their environment over time, were overcome.  相似文献   
164.
We analyzed two mid-Holocene (∼5000 years before present) individuals from North America that belong to mitochondrial DNA (mtDNA) haplogroup M, a common type found in East Asia, but one that has never before been reported in ancient or living indigenous populations in the Americas. This study provides evidence that the founding migrants of the Americas exhibited greater genetic diversity than previously recognized, prompting us to reconsider the widely accepted five-founder model that posits that the Americas were colonized by only five founding mtDNA lineages. Additional genetic studies of prehistoric remains in the Americas are likely to reveal important insights into the early population history of Native Americans. However, the usefulness of this information will be tempered by the ability of researchers to distinguish novel founding lineages from contamination and, as such, we recommend strategies to successfully accomplish this goal.  相似文献   
165.
The archaeological site of KHB-1, Oman, has been investigated in order to improve the chronological knowledge of the site, which is dated to the beginning of the fourth millennium B.C. on the basis of the archaeological context. Mollusc shells of the genus Anadara, coming from the uppermost layers of the site, have been dated using two different methods, radiocarbon and U-series technique. The results of the two techniques date the last occupational phase of the site from the end of the fourth millennium B.C. to the beginning of the third millennium B.C.  相似文献   
166.
UV-fluorescence microscopy provides a powerful tool for the assessment of the coherence of pollen and organic-walled microfossil assemblages in situations where recycling or the intrusion of younger pollen is suspected. It also provides sensitive information about the thermal maturity of pollen, important for assessing whether material has been heated. Examples are given from the Palaeolithic sites at Barnham, Suffolk, UK; Stanton Harcourt, Oxfordshire, UK; High Lodge, Suffolk, UK; Niah Cave, Sarawak, Malaysian Borneo; and Holocene sites at Wadi Dana, Jordan; Milldale and Creswell, Derbyshire, UK; and Dooncarton Mountain, County Mayo, Republic of Ireland.  相似文献   
167.
Radiocarbon and U-series methods (230Th/U and 231Pa/235U) for absolute age determination have been applied to some fossil samples from Grotta Juntu, in North Eastern Sardinia (Italy). The remains belong to the endemic deer species Praemegaceros cazioti, which is here represented by an almost complete skeleton. The three dating methods lead to concordant ages of about 7500 years BP, indicating that the skeleton was maintained as closed system after burial. Taking into consideration these results, Praemegaceros cazioti from Grotta Juntu is now the youngest representative of this species in Sardinia.  相似文献   
168.
《夏商周断代工程》是由人社会科学和自然科学的专家联合实施的系统工程,以多学科合作方式联合研究攻关,取得了一系列重要成果。1)根据考古系列样品的年代测定,得出考古学的^14C年代框架。2)依古献的天象记录,天计算定出懿王元年为公元前899年:武王克商年为公元前1046年;武丁登基年为公元前1250年;均与^14C测年结果相合。3)根据西周青铜器铭的纪时词语,排出金历谱,在年代框架内排出西周王年表。4)根据殷墟的甲骨和化分期,商后期的周祭祀谱,武丁年代和献记载,在年代框架内排出商后期王年的大致情况。5)商前期主要根据郑州商城和偃师商城的考古分期与年代测定,结合献,估定夏商分界的年代。6)夏代主要是根据二里头化分期和年代测定,王城岗化分期和年代测定,以及结合献和参考夏代的五星连珠、仲康日食等的天推算,估定夏代的始年。  相似文献   
169.
Tree-ring analysis provides chronological, environmental, and behavioral data to a wide variety of disciplines related to archaeology including architectural analysis, climatology, ecology, history, hydrology, resource economics, volcanology, and others. The pace of worldwide archaeological tree-ring research has accelerated in the last two decades, and significant contributions have recently been made in archaeological chronology and chronometry, paleoenvironmental reconstruction, and the study of human behavior in both the Old and New Worlds. This paper reviews a sample of recent contributions to tree-ring method, theory, and data, and makes some suggestions for future lines of research.  相似文献   
170.
Palaeomagnetic and geochemical studies of Cambrian–Ordovician serpentinite in the Highland Border Complex (HBC), a tectonic terrane along the Highland Boundary Fault (HBF) in Scotland, indicate that the HBF was a conduit for fluids in the Carboniferous–Permian. The fluids caused dolomitization, silicification, and haematite authigenesis. Both red dolomitized serpentinite and relatively unaltered serpentinite were sampled at multiple localities. The unaltered serpentinite contains a poorly defined magnetization with westerly declinations that resides in magnetite and has a pole which plots well off the apparent polar wander path. Most specimens of the red dolomitized serpentinite contain a magnetization with southerly declinations and negative inclinations that resides in haematite. A regional fold test suggests that this magnetization post‐dates tilting and the pole positions for the different locations fall on the Carboniferous to Permian part of the apparent polar wander path. In some specimens of red dolomitized serpentinite, alternating field (AF) demagnetization prior to thermal treatment removes a component with a similar direction. Dolomitized basement rocks along the fault contain a similar although apparently slightly older magnetization. Fluid inclusion and geochemical studies indicate that the fluids were hydrothermal in origin (110–240°C) and had a range of sources. The Carboniferous–Permian magnetization in haematite is interpreted as a chemical remanent magnetization that formed when warm fluids moved along the fault zone and caused haematite authigenesis. The component removed by AF treatment is interpreted as a thermal resetting of primary magnetite by the fluids. The variability of the palaeomagnetic, fluid inclusion, and stable isotope results suggests that there were probably multiple flow events that caused the alteration. The origin of the fluids could be related to the intrusion of late Carboniferous dikes in central Scotland and/or to reactivation of the HBF in the Carboniferous–Permian.  相似文献   
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