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41.
This paper presents 19 AMS radiocarbon dates from nine pre-Hispanic Caribbean (Taíno/Lucayan) wooden sculptures in the British Museum collections, provenanced to Jamaica, Hispaniola and the Bahamas. Together with strontium isotope results and wood and resin identifications, these data build a material and chronological context for some of the most recognised examples of Taíno art – from duhos (ceremonial seats) and cemís (free standing depictions of deities, ancestors and spirits) to canopied stands used to hold hallucinogenic drugs during the cohoba ceremony. Each sculpture widens our understanding of Caribbean carving traditions, stylistic variation, chronologies and material resource utilisation. A group of three sculptures recovered from Carpenters Mountains, Jamaica, carved by AD 1300 and brought together as a ceremonial ‘set’, each appear to have had their inlays renewed over a century later, suggesting long-term use. Three key examples of the main Caribbean duho categories (high-back, low-back and extended), provide insights into the diversity of styles present in the region post-AD 1100. The British Museum's corpus enables an exploration of regional styles, and potentially the work of individual artists.  相似文献   
42.
A combined archaeomagnetic and thermoluminescence study was carried out as part of a rescue archaeological excavation on a kiln discovered during the installation of methane gas pipelines beneath a rice field, along the southern border of Fontanetto Po village (Vercelli province, Italy). A total of 23 independent brick samples have been collected, oriented in situ with an inclinometer; the use of magnetic and sun compass was not possible due to the existence of metallic tubes beneath the kiln and a plastic cover above it. Standard archaeomagnetic procedures have been used for the determination of the archaeomagnetic inclination and absolute geomagnetic intensity. Stepwise thermal demagnetization shows a very stable characteristic remanent magnetization and the calculated mean inclination of the 23 samples is I = 65.3° with α95 = 2.4° and k = 156. Archaeointensity experiments have been performed using the classical Thellier method as modified by Coe, with regular partial thermoremanent magnetization (pTRM) checks. The cooling rate and remanence anisotropy effects upon thermoremanent magnetization (TRM) have been investigated in all the specimens. A total of 19 archaeointensity determinations (at specimen level) that correspond to linear NRM–TRM plots were used for the calculation of the site mean archaeointensity that is 46.4 ± 2.9 μT. Archaeomagnetic dating results show two possible dating intervals for the last 1000 years, calculated at 95% confidence interval: a first one from 1511 to 1614 AD, and a second one from 1768 to 1872 AD. Thermoluminescence (TL) study has been also performed on two brick samples from the kiln's internal wall, using conventional laboratory procedures. According to the thermoluminescence results the kiln's last usage lies between 1796 and 1914 AD. This age is in good agreement with the second dating interval obtained by the archaeomagnetic analysis. The combined archaeomagnetic and thermoluminescence results suggest that the last firing of the kiln could have occurred between the end of the 18th century and the beginning of 20th century.  相似文献   
43.
The Ecuadorian Formative was initially interpreted as a result of long-distance diffusion, and migration, more recent research has changed our perception of the Valdivia, Machalilla, and Chorrera culture complexes. In this analysis, these archaeological investigations are reassessed in order to reevaluate our understanding regarding the nature of these prehistoric cultures. Formative chronologies, distributions, interrelationships are reviewed in the light of Pre-Hispanic occupations in El Oro Province. Previous investigations on the Ecuadorian littoral are examined. Results indicate (1) Valdivia and Machalilla are part of the same ceramic tradition and (2) the interrelationships of these complexes to Late Formative Period ceramic sequences are more complex than previously assumed. (3) A major adaptive shift related to an increased dependence upon agriculture occurred during Valdivia VI–VIII, and continued into the Late Formative with the widespread distribution of Chorrera related material culture. (4) Long-distance interaction with the Ecuadorian highlands resulted in the spread of what may be termed a Chorrera horizon and formed the basis of subsequent Andean cosmology where it was symbolically represented according to local and regional artistic canons and over a vast area of Andean South America.  相似文献   
44.
Attempts have been made to date mortar by radiocarbon analysis. Potential problems are discussed, and the possible use of stable carbon isotopes to detect contamination by geological carbonates is investigated.  相似文献   
45.
This paper presents the first results of a new project investigating the provincial structure of the eastern Caucasus region in the late Antique and early Islamic periods. Excavations at the newly discovered rural archaeological site of Qarat?p? have so far revealed two phases of use: a burial ground dating to the 12th century a.d. and an unusually large earthen structure burnt in a catastrophic fire. Owing to the rapid abandonment of this building, whole ceramic and glass vessels were recovered from the fill of one of the rooms. The presence of charred seeds and roof timbers allowed for the acquisition of radiocarbon dates for the construction and abandonment of the building, placing the latter at the end of the 6th century a.d. These findings reveal crucial clues as to the transformation of the rural zone prior to the expansion of Islam, and a unique material assemblage dating from this period.  相似文献   
46.
In this article we address comments made by Bradley Lepper concerning our previously published article, “Radiocarbon Dates Reveal Serpent Mound is More than Two Thousand Years Old” (Romain, Herrmann, Monaghan, and Burks 2017). Further we offer commentary on the new radiocarbon dates provided by Lepper (this volume).  相似文献   
47.
Little is known of hard-rock coastal landsliding in Scotland. We identify 128 individual coastal landslides or landslide complexes >50 m wide along the coasts of Shetland. Most are apparently translational slides characterized by headscarps, displaced blocks and/or debris runout, but 13 deep-seated failures with tension cracks up to 200 m inland from cliff crests were also identified. Thirty-one sites exhibit evidence of at least localized recent activity. Landslide distribution is primarily determined by the distribution of coastal cliffs >30 m high, and they are preferentially developed on metasedimentary rocks. Analysis of 16 landslides on Fetlar (NE Shetland) indicates that most are translational dip-slip failures; 3 represent deep-seated failures and several exhibit active frontal erosion attributable to basal sapping by storm waves. As these landslides terminate in shallow water, failure was probably initiated when rising sea level resulted in footslope erosion and upslope propagation of instability, causing downslope displacement of landslide blocks on upper slopes. 10Be exposure dating of two headscarps yielded ages of 4.8?±?0.2 ka and 4.4?±?0.2 ka, consistent with the onset of footslope erosion as sea level rose. Our results suggest that landslides have played a hitherto undocumented but important role in retreat of cliffed coastlines in Scotland.  相似文献   
48.
Evidence of agricultural activity in Scotland during the Bronze Age is sparse. A bank system of that date, covered by a deep peat accumulation, in Argyllshire, Scotland has preserved a podzolic palaeosol. Palynological investigation of the palaeosol allows a consideration of potential prehistoric land use. The existence of a well developed iron pan in the palaeosol divides the soil pollen into two contrasting groups, suggesting two quite distinctive periods of land use. Also discussed are the problems which the processes of podzolization cause pollen analysts, the dating of buried soils and the possibility of periodicity in pollen movement through a soil.  相似文献   
49.
In the early 1900s shells of a large freshwater mussel, Margaritifera auricularia (Spengler), were discovered in calcreted gravel dredged from the channel of the Thames at several sites between Mortlake and Battersea in west London. These specimens were said to have been associated with Neolithic polished stone axes, supposedly as food remains. M. auricularia is now extinct in Britain, but it has been reported living in several large rivers in southern Europe although apparently not in recent years. Three radiocarbon dates of 4140±50, 4340±45 and 4860±40 bp have been obtained from Thames specimens, supporting a Neolithic age for these shells. The theory that the shells represent debris from imported human food is discounted and it is considered more likely that M. auricularia was actually living in the Thames in Neolithic times. Its extinction in Britain should be seen as part of a general recession during the Post-glacial, as revealed by fossil occurrences to the north and east of its present-day range.  相似文献   
50.
Over a period of some 100 years it has gradually been accepted that the human skeletal remains found in the late nineteenth century in ancient gravels at Galley Hill, Kent are not those of early man, but are of much more recent date. This conclusion was finally verified by means of relative (N, F) and absolute (14C) dating. Here we present the results of further analysis of the remains from Galley Hill for their uranium content by a method having general application to the relative dating of fossil human and other mammalian bone.  相似文献   
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