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991.
992.
Many caves in Sierra de Atapuerca contain archaeological and anthropological remains from the Early Pleistocene until the Holocene. The fi rst half of the Late Pleistocene (MIS 4 and 3) has only been detected in open air deposits discovered on the basis of total cover surface surveys. Excavation at one of them, Hundidero, began in 2004. The Middle Paleolithic tool record spans the period between 70 ka and 56 ka. The technological and typological features of Hundidero, along with records from 30 other contemporary open air sites at Atapuerca, suggest repeated visits by Neanderthals who shared the same cultural tradition, characterized by expedient tool production, a diversity of exploitation techniques, a microlithic tendency, a search for dorsal faces, and the reuse of previous tools. These characteristics do not seem to depend on the conditions of the raw materials, the climate or the group's activities.  相似文献   
993.
994.
María Gutiérrez 《对极》2011,43(3):639-661
Abstract: This article traces the creation of a market for carbon sequestration by trees under the Kyoto Protocol on climate change, describing the problems encountered by UN negotiators as they attempted to abstract, isolate, quantify and commodify a process akin to breathing, which takes place naturally everywhere, anyway. It starts with an overview of the history of the negotiations that defined the commodity and the rules to govern its trade, creating the scarcity conditions for the market to work. It then goes over the key problems encountered and how they were solved. The analysis draws attention to time and risk as critical elements in reproducing uneven development, and suggests that this new market can be understood as an instance of capital involution—that is, an instance where a narrow pattern persistently repeated leads to ever increasing complexity but, instead of evolving into something new, it generates further entrapment.  相似文献   
995.
Aleut population history has been a topic of debate since the earliest archaeological investigations in the region. In this paper, we use stable isotope chemistry to evaluate the hypothesis that two distinct groups of people, Paleo- and Neo-Aleut, occupied the eastern Aleutians after 1000 BP. This study focuses on 80 sets of directly dated eastern Aleutian burial assemblages from Chaluka midden, Shiprock Island and Kagamil Island. We use a linear mixing model informed by isotopic analysis of two large Aleut faunal assemblages to address temporal and spatial variation in human carbon and nitrogen stable isotope data from these sites. The patterning we report addresses both Aleut demographic and economic prehistory, illustrating a transition in both at ca. 1000 BP. Our results suggests that the Chaluka diet, dominated by Paleo-Aleut inhumations, differed in both trophic level and foraging location from the other two sites for much of the past 4000 years. Trends in our data also suggest that individuals from Shiprock and Kagamil burial caves, primarily Neo-Aleuts, had enough access to higher trophic level foods to differentiate their bone chemistries from those buried in Chaluka midden. These trends in diet, recently reported genetic differences, as well as the introduction of novel mortuary practices at ca. 1000 BP, suggest that Neo-Aleuts do represent a population new to the eastern Aleutians.  相似文献   
996.
Archaeometrological analysis has traditionally involved reconstructing the originally intended mass of a weight by hand; measuring with a calliper or a profile microscope, as well as using the artefact’s displacement in water for factors such as volume and density. Ideally, corrosion was to be left intact, which is inconsistent with the goals of the conservationist. In all, the process was time consuming and may in some cases even have accelerated the deterioration of the artefacts.  相似文献   
997.
Although there are many archaeological and ethnographic evidences for the use of slate and similar rocks for flaking purpose, they raised little interest among specialists, leading to a general ignorance of specific problems associated with these raw materials. Starting from the study of several Neolithic and Chalcolithic slate collections of the Western Iberia, the mechanical properties of slate and its impact on knapping process has been defined; subsequently, manufacturing and use of slate and phyllite projectiles have been undertaken. The results show that the ease with which these materials break into sheets of uniform thickness and morphology would provide an ideal basis for a fast and easy manufacture of arrowheads. In addition, these projectiles have shown a penetration capability and resistance statistically equivalent to those made on more standard materials (i.e. chalcedony or rock crystal). Therefore, slate and other rocks with a high degree of fissility would have been very attractive to prehistoric knappers endeavouring to make arrowheads.  相似文献   
998.
This report presents the results of using NASA/JPL airborne synthetic aperture radar data (AIRSAR) to detect ancient Maya settlements beneath jungle canopy in Guatemala. AIRSAR stands out from previous applications of radar remote sensing in the Maya lowlands because of its canopy-penetrating capabilities. The authors offer an overview of the AIRSAR technology, followed by a case study in which the AIRSAR data receive testing in the field. Reconnaissance in the region around the Maya site of El Zotz led to the discovery of two new sites, including the medium-sized settlement of La Avispa. AIRSAR also aided archaeologists in detecting zones of residential settlement around the site core of El Zotz. This research will serve as a guide for future applications of radar remote sensing in Maya archaeology.  相似文献   
999.
The small mammal accumulations in the Pleistocene deposits of Karain Cave are investigated to identify the predators and possible biases in the fossil assemblages. Seven small mammal assemblages are studied in chronological order from two chambers of the cave, the main chamber E and the side chamber B. The lowermost level within the whole sequence is Proto-Charentien, which corresponds to an early stage of the Middle Palaeolithic. The main part of the material belongs to Middle Palaeolithic layers. The most important aspect of the fossil record in the cave is the human occupation without any interruption through the Pleistocene to Holocene. The small mammal fossil evidence in the cave denotes the presence of opportunistic predators throughout the sequence with one exception, and these produce balanced samples of small mammal faunas in the habitat. The lack of bias in the small mammal faunas allow the interpretation of local environments, showing that partial steppe and arid conditions existed during deposition of the lowermost levels of the Middle Palaeolithic in Karain Cave and that these shifted into more temperate and wooded habitat in the upper levels. Evidence from the side chamber indicates some differences, with a more open grassy environment. In the Mediterranean part of Anatolia the temperate and moist conditions in the Middle Palaeolithic were superseded by more arid conditions in the Upper Palaeolithic, followed by a decrease in steppe conditions during the Epi-Palaeolithic period.  相似文献   
1000.
The use of feldspar for luminescence dating has been restricted because of anomalous fading. This has made its application to several important geological problems such as volcanic terrains difficult. Presently, two correction procedures are used to correct for anomalous fading. The present study tests these correction procedures using volcanic samples of known ages spanning the time period of 400 ka to 2.2 Ma. These correction procedures provided grossly underestimated ages (up to 60%). The possible causes for the underestimation are discussed.  相似文献   
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