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71.
In order to carry out strontium (Sr) isotope analysis, glass artefacts from South Asia were sampled with portable laser ablation (pLA), a relatively novel sampling technique that leaves damage invisible to the naked eye. Subsequently, thermal ionization mass spectrometry (TIMS) was used to obtain Sr isotope ratios after sample dissolution and separation. In this study, the goal was twofold: to determine whether the measurements of Sr isotope ratios were impacted by using a portable laser as a sample tool; and to assess the pertinence of using Sr isotope ratios to provenance Indian glass. Despite a deterioration in the precision of the measurement of the Sr isotope ratios for artefacts sampled with pLA compared with the traditional sampling method, the Sr isotope ratios of certain Indian glass are so different that this does not affect their separation but a comparison of data sets obtained using standard methods and pLA might be challenging.  相似文献   
72.
The reasons why the Western Mediterranean, especially Carthage and Rome, resisted monetization relative to the Eastern Mediterranean are still unclear. We address this question by combining lead (Pb) and silver (Ag) isotope abundances in silver coinage from the Aegean, Magna Graecia, Carthage and Roman Republic. The clear relationships observed between 109Ag/107Ag and 208Pb/206Pb reflect the mixing of silver ores or silver objects with Pb metal used for cupellation. The combined analysis of Ag and Pb isotopes reveals important information about the technology of smelting. The Greek world extracted Ag and Pb from associated ores, whereas, on the Iberian Peninsula, Carthaginians and Republican‐era Romans applied Phoenician cupellation techniques and added exotic Pb to Pb‐poor Ag ores. Massive Ag recupellation is observed in Rome during the Second Punic War. After defeating the Carthaginians and the Macedonians in the late second century bce , the Romans brought together the efficient, millennium‐old techniques of silver extraction of the Phoenicians, who considered this metal a simple commodity, with the monetization of the economy introduced by the Greeks.  相似文献   
73.
Prompted by a series of panel sessions at a recent American Association of Geographers annual meeting entitled “A Globe‐Shaped Crystal Ball: The Next Fifty Years of Geographical Analysis,” participants were asked to speculate on the future of the journal, which of course has broader implications for spatial and geographic analytics. In what follows, I provide my thoughts on the journal as a reader, contributor, referee, and former editor of Geographical Analysis. The major points touched upon include the following. First, application to address substantive concerns will come to dominate the field. Second, the spatial data deluge will continue unabated, but will lead to important advances because of better detail and less abstraction of reality. Third, analytical methods will evolve specifically for big data. Fourth, the point‐and‐click revolution will result in ever more use of spatial analytics, but also will lend itself to greater and more widespread abuse of these methods. Fifth, addressing assumptions and theoretical foundations of long utilized approaches will revolutionize a new generation of spatial analytics. Sixth, geographic uncertainty and bias will be more than an afterthought, and methods will emerge to support meaningful analysis. Finally, spatial optimization will have increased prominence in fundamental analysis, particularly associated with establishing and evaluating significance.  相似文献   
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The raw material used largely determines the type and quality of porcelain produced. Twenty-three raw materials used for making Ding, Xing, Gongxian and Dehua porcelain bodies were studied using principal component analysis. Results show that for Dehua wares, only one raw material was used. For Ding wares, although there were many possible raw materials, the use of one alone is unlikely. Lingshan clay was the main raw material but it has to be mixed with other raw materials: Pinjiawa clay, quartz, feldspar and dolomite. The Xing pieces can be divided into three groups and Gongxian wares into two groups, which are discussed in detail.  相似文献   
76.
Nestorian Crosses from Jabal Berri   总被引:1,自引:1,他引:0  
Two small crosses, one of bronze and the other of mother-of-pearl, from the surface of a site near Jabal Berri in northeastern Saudi Arabia are presented. They are attributed to the Nestorian community of Bet Qatraye which is known from literary sources to have flourished during the Sasanian period.  相似文献   
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Several samples of geological stones from statuary pedestals found in various archaeological sites in Cyprus have been characterized using non-contact laser infrared photothermal radiometry. Thermal diffusivities and effective optical absorption coefficients were calculated using a one-dimensional thermal-wave model. The mean values and standard deviations were tabulated and comparisons were made with lithographic and petrographic studies of the samples. Good correlations were found, thus demonstrating that laser photothermal archaeometry is a promising methodology for the accurate, potentially non-destructive and convenient characterization of the origins of ancient stones in Cyprus and other geological and archaeological sites.  相似文献   
79.
Born in Boston, Massachusetts, in 1947, Linenthal earned his bachelor's degree in religious studies at Western Michigan University, his master's degree in divinity at the Pacific School of Religion, and his Ph.D. in religious studies at the University of California, Santa Barbara. He is Professor of Religion and American Culture at the University of Wisconsin, Oshkosh. His books include: Symbolic Defense: The Cultural Significance of the Strategic Defense Initiative (1989); Sacred Ground: Americans and their Battlefields (2nd edition, 1993); Preserving Memory: The Struggle to Create America's Holocaust Museum (1995); American Sacred Space (co-editor, 1995). He is writing a history of the A-Bomb controversy that will appear in a book to be published in 1996. Linenthal has often lectured about controversial historic sites for National Park Service staff. At the USS Arizona Memorial, Linenthal delivered a commemorative address on 7 December 1994, on the 53rd anniversary of the attack on Pearl Harbor. Linenthal and his wife, with their two sons, reside in Oshkosh, Wisconsin. Linenthal was the only historian to testify before the Senate Committee on Rules and Administration about the National Air and Space Museum's ill-fated exhibit, “The Last Act: The Atomic Bomb and the End of World War II.” What follows is Linenthal's Senate statement and comments he has written for The Historian.  相似文献   
80.
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