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Yeha, in Tigray, is the most impressive site with evidence for South Arabian influence dating to the first millennium BC in the northern Horn of Africa (Eritrea and northern Ethiopia). The evidence from this site was used to identify a ‘Pre-Aksumite’ or ‘Ethiopian-Sabean’ Period (mid-first millennium BC) when an early Afro-Arabian state apparently arose in the region. A ‘Pre-Aksumite Culture’, characterised by South Arabian elements, was also suggested as a distinctive archaeological culture in northern Ethiopia and Eritrea. However, recent fieldwork in these countries suggests that a Pre-Aksumite culture actually did not exist and South Arabian features were restricted to a few sites, which were scattered in a mosaic of different archaeological cultures in the first millennium BC. This hypothesis is tested through a comparison between the ceramics from Yeha and those from Matara and other sites of the first millennium BC in Tigray and Eritrea.  相似文献   
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Several decades after the discovery of the spectacular Nahal Mishmar Hoard (a collection of cast metal goods, some quite ornate, found in a cave high in the cliffs of the Judean Desert) many important questions about Chalcolithic metallurgy in the southern Levant remain unanswered. What is the origin of the materials used? Where were the final goods produced and what were the dynamics of production? In fact, new questions have also arisen as recent discoveries force us to reconsider previous interpretations of Chalcolithic metallurgy and the societies within which it evolved. Such will be the focus of this paper.  相似文献   
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The interim Egyptian government's excoriation of U.S. support for nongovernmental organizations (NGOs) in the country has sparked a crisis that some analysts have called the worst deterioration of United States–Egypt relations in history. As Cairo's smear campaigns against the civil society community foment public mistrust among many Egyptians of NGO activity and foreign funding, U.S. policymakers and practitioners face new challenges in supporting civil society work in Egypt. For a number of reasons, however, Washington's assistance to Egypt should and almost certainly will continue, even if the environment for civil society activity in the country does not improve. Grantors and implementers must think seriously, therefore, about long‐term strategies for assisting civil society development in Egypt, which will require at least some coordination with a government that may be suspicious of U.S. efforts. By standing firm on red lines, improving public messaging in Egypt, carefully fostering local ownership of projects, remaining strictly neutral in identifying grantees and diversifying partnerships, distinguishing between short‐term foreign policy objectives and long‐term efforts to assist civil society development, and using varied democracy assistance tools appropriately, the United States can assist NGOs in Egypt in a way that gives them—and democracy—the best chance for success.  相似文献   
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The loess site at Boynychi (the Volyn Upland) is of essential importance for the stratigraphy of Middle and Upper Pleistocene in Central Europe. The profile was recently dated by Fedorowicz and Prylypko in 2007 (parallel dating), and by Kusiak in 2009. The Upper Vistulian loesses are much thicker in the exposure from 2009 than in the earlier examined one (2007). The list of results obtained in the Gdańsk, Kiev and Lublin laboratories, respectively, can be divided in two. The first group contains the results obtained for the Horohiv and Korshiv pedocomplexes and for the loess from the penultimate glacial, which separates these pedocomplexes. The results from all laboratories are very similar and rather well describe the real age of dated deposits. The second group contains the widely differing results of dating of the Vistulian loesses. The TL ages obtained by Fedorowicz and Prylypko are considerably older than those obtained by Kusiak in the new exposure. The latter ones excellently correspond to the geologic-stratigraphic interpretation of the profile. Two incompatible series of TL dating results indicate that local variability of loess accumulation conditions in different stages of their formation may have resulted in incomplete luminescence zeroing of mineral material before deposition.  相似文献   
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Lime mortars may contain carbon from different origins. If the mortars are made of totally burnt lime, radiocarbon dating yields the true age of building construction. The presence of carbonaceous aggregates gives the so-called dead carbon effect, which may generate older ages. Another source of carbon is charcoal present in mortars. An attempt has been made to apply the radiocarbon method to mortars of archaeologically estimated age from the Dead Sea region. Petrographical analyses of these samples show the carbonaceous character of the binder and large amounts of limestone aggregate. Determination of the mineral composition of the mortars and comparison with the geology of the surrounding, allows the provenance of the raw materials to be identified. They probably represent the Cretaceous rocks of the Judea Group. Separate radiocarbon dates were made on bulk mortar samples, binder, charcoal fragments and separated fractions from mortars. In the case of binder-aggregate mixture the reservoir effect correction has been applied.  相似文献   
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