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991.
豫东商丘考古调查与南亳问题   总被引:1,自引:0,他引:1  
文献记载,商丘地区为汤都南亳所在地。本文根据对考古调查材料的分析,认为,邹衡先生从考古学角度否定南亳是有道理的,商汤亳都只有一处即郑州商城。  相似文献   
992.
本文把近代以来新疆艺术发展划分成三个阶段,对各艺术种类在不同时期的演变进行了概括性的研究,认为新疆艺术和中国政治社会变化密切相关,各阶段的新疆艺术既有其鲜明的时代烙印,也深刻地体现着其独具的传统特点;虽然新疆艺术受东、西方文化和艺术潮流的影响,但是此期中国内地艺术的影响深刻而全面。  相似文献   
993.
略论花园口决堤与泛区生态环境的恶化   总被引:4,自引:1,他引:3  
花园口决堤,造成黄河历史上第一次人为的改道。黄河在夺淮入海途中,挟带巨量泥沙肆意漫决,形成了大范围的黄泛区,严重破坏了泛区原有的生态环境。生态环境的恶化给泛区的经济、社会生活造成了长期的负面影响。  相似文献   
994.
Tantura B is by far the first early Islamic shipwreck to be discovered off the Palestinian coast. Scientific evidence indicates that this vessel sank some time between the mid-8th and the mid-9th centuries. Neither archaeological remains nor historical sources can ascertain its exact function and origin due to the lack of circumstantial documentary evidence. However, it has been argued that the vessel could be either a coaster, capable of entering rivers or estuaries, or a support vessel operating in the Arab fleet, i.e. , it may have had been used for either military or civil purposes, or both.
© 2005 The Nautical Archaeology Society  相似文献   
995.
996.
The paper presents proxies from an interdisciplinary geoarchaeological working group. Sediment analyses and geomorphological studies, radiocarbon ages of snail shells and luminescence dating of loess allow a preliminary chronology of the environmental evolution of the eastern Atacama desert, Nazca–Palpa region (southern Peru). Until now, typical desert loess was unknown from the arid western flank of the Andes (southern Peru). The loess points to periods of more humid conditions with open grasslands at the eastern Atacama desert margin in the early and middle Holocene. In the footzone of the Andes, aridification set in before the Paracas Culture (c. 800–200 bc ) evolved, but the Cordillera Occidental remained semi‐arid. A second push of increasing aridity started at the latest in the Middle Nazca Period (after ad 250). During this time, the Nazca settlement centres moved upstream through the river oasis, following the eastward‐shifting desert margin. It is possible that culminating aridity after ad 600 caused the collapse of the Nazca civilization. During the Late Intermediate Period (ad 1000–1400), more humid conditions favoured the massive reoccupation of the eastern Atacama up to a distance of about 40 km from the Pacific coast. Since the 14th and 15th centuries, the Palpa region has again been part of the hyper‐arid Atacama. The study shows that in the Nazca–Ica region, the deep cultural changes of Pre‐Columbian civilizations were not caused by catastrophic run‐off of El Niño events, but by a shifting eastern desert margin due to the changing monsoonal influence.  相似文献   
997.
The Republican and early Imperial monuments of Rome are, for the most part, built of tuffs quarried from at least seven pyroclastic deposits erupted from nearby Monti Sabatini and Alban Hills volcanoes. Remarks by Vitruvius (2.7.1–5), field observations of the monuments, and petrographic and rock testing studies of samples from Roman quarries demonstrate that Roman builders developed a good knowledge of the diverse material properties of the tuffs over centuries of use and exposure. Measurements of compressive strength, specific gravity, water absorption and adsorption of water vapour confirm that the petrographic characteristics of each tuff lithology strongly influence its strength and durability. Early construction utilized weakly durable, soft or vitric tuffs such as Tufo del Palatino or Tufo Giallo della Via Tiberina that are susceptible to decay, as at Temple C (290 bc ) of the Largo Argentina Sacred Area. Late Republican structures, such as the Temple of Portunus (80–90 bc ), employed somewhat durable, vitric–lithic Tufo Lionato reinforced with travertine, a durable limestone quarried near Tivoli. Roman builders selected the material properties of the tuffs to advantage for specific structural elements within large public monuments of the first century bc and the first century ad , as at the tabernae of the Forum of Caesar (46 bc ), where an upper storey of lightweight Tufo Lionato is supported by robust, lithic–crystal Lapis Gabinus pillars and flat arches reinforced with travertine. The tuffs are not very durable building stones; Romans preserved them with protective stucco, and travertine and marble cladding. Their high water intake, coupled with direct exposure to rain, daily fluctuations in relative humidity and urban weathering at present makes them especially vulnerable to decay.  相似文献   
998.
A novel luminescence methodology for dating surfaces of granitoid rocks is presented, with encouraging results for archaeological stone structures. It is based on the zeroing of the latent signal of optically stimulated luminescence (OSL) in feldspar and quartz grains of the stone surface during exposure to daylight. When after bleaching the surface is shielded from light, the OSL signal builds up again, such that its intensity provides an age for the event of the last exposure to light. This event could be the construction or the destruction of stone structures or, for example, sedimentary deposition of granitic boulders, such as in fan deposits. The experimental approach utilizes a high spatial resolution detection technique (HR‐OSL) for OSL of minerals that are left in their original petrological context; that is, without any mineral separation. With this approach, steep gradients in microdosimetry at the surface and at grain boundaries become important and are discussed in detail. The new dating technique is successfully applied to a stone wall of the medieval castle of Lindenfels in southwestern Germany and the pre‐Columbian Nasca lines (geoglyphs) around Palpa in southern Peru.  相似文献   
999.
This paper reports on the comparative evaluation of traditional and innovative methods for the investigation of mortar technology. Preliminary results of various approaches to determining the mix proportions in lime mortars with carbonate aggregate are presented. Quantitative analysis was tested on ad hoc prepared mortars of known composition containing carbonate aggregates of different origin (travertine and Bath limestone). Wet chemical methods, manual disaggregation and Digital Image Analysis of thin sections and cross‐sections stained with Alizarin Red S were tested. The advantages and drawbacks of the different approaches are discussed, and applications to the analysis of archaeological mortars and plasters are highlighted.  相似文献   
1000.
Work hard, play hard: selling Kelowna, BC, as year-round playground   总被引:1,自引:1,他引:0  
A keen interest in place making and place selling is widespread in contemporary society. While the bulk of academic research has focused on studying the restructuring of large urban conglomerates, places beyond the exploding metropolis, by comparison, have received little attention, especially when it concerns Canadian landscapes. In an attempt to study the particularities of place making in contemporary smaller, more isolated communities—hinterlands—this work analyses the city of Kelowna, in British Columbia, Canada. We argue that historically Kelowna, a small rural community specialising in ranching, forestry and fruit production, since the early 1980s, has been re-imagined and re-designed, on the one hand as an all-year playground and as an innovative frontier for high-tech industries; on the other hand, this post-Fordist reinvention contains a discourse of 'whiteness', one that entices by packaging 'place' in terms of 'sameness' and 'familiarity'. In contrast to large cosmopolitan post-industrial cities, hinterland-type cities are invented, sought and lived as geographies cleared from the 'elements' that make cities 'unsafe'.  相似文献   
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