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991.
The transformation of yellow goethite into red hematite by heating has long been assumed for Palaeolithic red artefacts excavated close to fireplaces. However, this transformation is extremely rare. Using SEM–FEG–EDX, PIXE–PIGE, TEM and μXRD, we characterized the mineralogical and chemical compositions of four microsamples of colouring materials from the Mousterian layer B in the es‐Skhul rock‐shelter, from about 100 kya ago. For some colouring materials, the Mousterian people of es‐Skhul chose to gather remote yellow lumps for heating. Their significant transport distance provides evidence of the possible high cultural value of these colouring materials for transformation into red pigments.  相似文献   
992.
This paper is aimed at defining the artistic technique performed by the outstanding artist Isidoro Bianchi for the Baroque stucco decorations in the church of Santa Maria dei Ghirli (Campione d'Italia, Italy). Samples of stucco were examined by means of optical microscopy, scanning electron microscopy with a microprobe, X‐ray powder diffraction, Fourier transform infrared spectroscopy, gas chromatography–mass spectrometry and laser ablation mass spectrometry equipped with plasma source spectrometry. On the basis of the results obtained, art historians have made new hypotheses on the biography of the artist and on the historical location of his birthplace.  相似文献   
993.
994.
Intra‐individual variations in carbon (δ13C) and nitrogen (δ15N) isotope measurements of dentine collagen in ungulate teeth can be related to diet and environmental changes at different periods during the life of the animal. A protocol of serial sampling of first, second and third molar roots was applied to modern caribou (17–27 months old) of the Qamanirjuaq herd (Rangifer tarandus groenlandicus), Canada. Based on a previous study, we predicted that M2 would reflect winter, M3 summer and M1 a complete year in terms of the isotopic record. Relatively high δ15N values (ca. 6 to 8‰), previously attributed to winter stress, were found in different molars of different specimens, reflecting a period of growth between April 1966 to April 1967. Previous results on other teeth from the same population confirmed that a high δ15Ncoll value signal corresponded to the winter of 1966/67. This temporary increase in δ15N value was probably linked to diet and/or environmental change. Collagen from M1 reflects the first winter whereas M2 and M3 reflect the second winter of life of young caribou. A longer time record including summer is represented by the bone collagen of the mandible. Results obtained on molar roots and mandible bone of the modern caribou of Banks Island herd (Rangifer tarandus pearyi) confirmed this seasonal record. Such collagen isotopic analysis on M1, M2 and M3 roots and jawbone can be applied to reindeer found in archaeological sites. Mandibles retaining deciduous premolars are preferable to avoid the possible loss of the winter tooth signal observed in animals older than 2 years. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
995.
The elemental fluxes and heat flow associated with large aquifer systems can be significant both at local and at regional scales. In fact, large amounts of heat transported by regional groundwater flow can affect the subsurface thermal regime, and the amount of matter discharged towards the surface by large spring systems can be significant relative to the elemental fluxes of surface waters. The Narni‐Amelia regional aquifer system (Central Italy) discharges more than 13 m3 sec?1 of groundwater characterised by a slight thermal anomaly, high salinity and high pCO2. During circulation in the regional aquifer, groundwater reacts with the host rocks (dolostones, limestones and evaporites) and mixes with deep CO2‐rich fluids of mantle origin. These processes transfer large amounts of dissolved substances, in particular carbon dioxide, and a considerable amount of heat towards the surface. Because practically all the water circulating in the Narni‐Amelia system is discharged by few large springs (Stifone‐Montoro), the mass and energy balance of these springs can give a good estimation of the mass and heat transported from the entire system towards the surface. By means of a detailed mass and balance of the aquifer and considering the soil CO2 fluxes measured from the main gas emission of the region, we computed a total CO2 discharge of about 7.8 × 109 mol a?1 for the whole Narni‐Amelia system. Finally, considering the enthalpy difference between infiltrating water and water discharged by the springs, we computed an advective heat transfer related to groundwater flow of 410 ± 50 MW.  相似文献   
996.
Relying heavily on the work of Edward Shils, this paper argues that a robust sense of national identity among the peoples of East Central Europe played a crucial role in the revolutions of 1989 and the subsequent emergence of civil society in the region's countries.  相似文献   
997.
Maxillary and frontal sinusitis, cribra orbitalia and linear enamel hypoplasia were recorded as indicators of nutritional and environmentally related stress in an Early Iron Age (0–260 AD ) population from Sweden. The material comprised the skeletal remains of 99 adults and 45 subadults (aged 20 years and under). Maxillary sinusitis and cribra orbitalia were recorded in the majority of subadults and adults. In contrast, linear enamel hypoplasia was uncommon and occurred mainly in the subadults. In seven cases (12.7%) there was a clear co‐occurrence of periapical lesions and maxillary sinusitis. A significant co‐occurrence of maxillary sinusitis and frontal sinusitis was found in the adults. The least common combination in sex‐determined adults was cribra orbitalia and enamel hypoplasia, only 7.7% exhibiting both lesions. The significantly higher incidence of this combination among subadults suggests an association with life‐threatening conditions. Overall, the results showed that the Early Iron Age community studied suffered foremost from upper respiratory diseases. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
998.
The mineralized fracture system that underlay paleo‐fumarole field at Chinkuashih, Taiwan has been exposed by copper–gold mining to depths of about 550 m below the paleo‐surface. Its mineralogy and systematic variations in metal and semimetal (Fe, Cu, As, Sb, Bi, Hg, Cd, Sn, Zn, Pb, Se, Te, Au, Ag) concentrations provide insights into the chemical responses of a magmatic‐vapor phase as it expands through fracture arrays to the surface and discharges as fumaroles associated with more extensive solfatara. At Chinkuashih, following initial sealing of the fractures by silica‐alunite alteration, brittle failure reestablished discharge from an underlying reservoir of magmatic vapor. Crystalline pyrite was deposited first in the fractures and was succeeded and replaced by ‘enargite’ (Cu3(As,Sb)S4) as sulfosalt encrustations (‘sublimate’) on fracture surfaces and in extensional cracks. Subsequent recrystallization resulted in complex exsolution intergrowths with antimony fractionation to the evolving crystal–vapor interface. Heavy metal fractionation between sulfosalt and vapor enriched the vapor phase in heavy metals that subsequently precipitated as complex Bi–Hg–Sn sulfosalts in discrete areas (paleo‐fumaroles) close to the paleo‐surface in a manner analogous to modern‐day fumaroles on active volcanoes such as Vulcano, Italy. As in similar paleo‐fumaroles (e.g., El Indio, Chile and Lepanto, Philippines), the most characteristic reaction sequence is the partial replacement of the early pyrite by enargite and Fe‐tennantite. It is proposed that this reaction tracks the decrease in the pressure of the underlying magmatic‐vapor reservoir because of the sustained discharge of vapor to the surface.  相似文献   
999.
ABSTRACT. This article critiques the ‘cultural turn’ in Italian Risorgimento historiography by examining Italian Switzerland, and specifically Ticino. This area paradoxically aided and abetted Italian patriots, especially Giuseppe Mazzini, yet rejected becoming part of the Italian national project. This paradox is heightened by the fact that the vast majority of the Italian nationalist literary canon, as identified by Alberto Maria Banti, was republished in Ticino. The paradox is explained in terms of the conflict between long‐standing traditions of local autonomy and the idea of any form of uniform or centralised control, as originally represented by the Cisalpine Republic and then by both versions (Napoleonic and Piedmontese) of the Kingdom of Italy. However, I also use Banti's cultural concepts to demonstrate the creation of a powerful counter‐myth of Italian Swiss nationalism in the character of William Tell.  相似文献   
1000.
A series of radiocarbon dates for the Late Neolithic burial at Kyordyughen, Yakutia, support its association with the Ymyiakhtakh culture. The article proposes a new interpretation of the burial rite in the context of the site. Possible reasons for the disruption of the burial are presented. The presence of the dismembered remains of another body may indicate the practice of human sacrifice. The emergence of warriors as a social group is discussed, and the question is raised as to whether such a group might have been present in the Late Neolithic societies of northeast Asia on the basis of evidence favoring social differentiation with regard to military status.  相似文献   
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