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101.
M. Le Goff  Y. Gallet 《Archaeometry》2015,57(5):897-910
The rehydroxylation (RHX) dating method applicable to virtually all baked clay fragments still requires testing and new developments. Here, we have obtained new weighing measurements from Syrian medieval ceramic fragments. In particular, they allow us to illustrate the scatter in RHX behaviour that may exist between different potsherds of the same age and found at the same archaeological site, thus having experienced the same effective lifetime temperature, and even between samples collected from the same artefact. Thanks to a so‐called time‐span analysis, we also report on some complexities in data sets previously obtained by Wilson et al. (2009, 2012, 2014).  相似文献   
102.
The small mineral-binding bone protein, osteocalcin, has been applied in a number of studies on ancient bone due to predictions of its long-term stability. However, the intact protein has not been shown to survive in ancient bone devoid of DNA, which is a much more phylogenetically informative biomolecule. In this investigation, the survival of osteocalcin is directly compared to the amplification of mtDNA in a set of 34 archaeological samples from four sites throughout Europe. We also present unpublished osteocalcin sequences of seven mammalian species in addition to the 19 published sequences to highlight phylogenetic limitations of this protein. The results indicate that the intact osteocalcin molecule survives less in archaeological samples than mtDNA and is more subject to the temperature of the archaeological site. Amino acid analyses show the persistence of the dominant protein collagen in samples that failed both osteocalcin and mtDNA analyses. The implications these findings present for biomolecular species identification in archaeological and palaeontological material are that, although proteins do survive beyond ancient DNA, osteocalcin does not appear to be the most ideal target.  相似文献   
103.
The recovery of historic memory of the Spanish Civil War is a multilayered initiative to escape both the romanticism of the Franco era, in which only the glory of the victors was celebrated while their past atrocities were ignored, and the cautiousness of the post-Franco democracy, for which forced amnesia of the Civil War was considered a sacrifice for the greater good. In the past five years the efforts to recover historic memory have gained empirical footing by employing archaeological methods to locate, enumerate and identify the victims of extrajudicial executions. The ultimate goals of such work include the production of a more accurate historical statement of past events, the repatriation of missing persons to their families, and the documentation of physical evidence that may allow families to seek civil restitutions. While the scientific methodology is fairly straightforward, the process is nonetheless inherently political in that various government bodies can and do impede recovery efforts. This paper contextualizes the current political and social climate of human rights investigations in Spain by illustrating some of the recent recovery efforts in Catalonia and Andalucia.  相似文献   
104.
Fishing was the foundation for many of the world's foraging peoples and was undertaken using a variety of technologies. Reconstructing fishing technologies can be difficult because these tools were often made of perishable materials. Here we explore fishing technologies employed at the Ityrkhei site on Lake Baikal, Siberia. Specifically, we employ regression analyses to reconstruct the sizes of perch (Perca fluviatilis) captured through time at the site. Our analyses demonstrate that almost no juvenile perch were taken, suggesting some selectivity in harvest. We suggest this selectivity is most consistent with the use of relatively large gauge nets or traps. Such mass harvesting technologies may have been important elements of the subsistence economies of Lake Baikal's foraging peoples throughout much of the Holocene.  相似文献   
105.
Extraordinarily well-preserved organic remains from mortuary and settlement sites, including mummified bodies, are scattered along the outer, oasis-laden rim of the Tarim Basin in Xinjiang Province, China, ranging in date from about 1400 BC to the late first millennium BC. Specimens of textile finds from Chärchän, dated at about 1000 BC were selected for dye analysis using newly developed protocols employing high performance liquid chromatography with spectrophotometric and mass spectrometric detection. A single blue (from an indigo plant), a red (from madder, a Rubia species) and two yellow dyes were detected, although the exact plant source for none of them could be identified with certainty. This research offers new insights in the interpretation of textile finds from prehistoric Xinjiang, and more generally, of early Bronze Age Eurasia.  相似文献   
106.
大气颗粒物是潜在威胁遗址与文物的一种大气污染物,颗粒物沉降或吸附后覆盖文物表面细节,降低其审美价值,并带来进一步的物理或化学侵蚀。通过分析莫高窟开放洞窟(16窟、257窟)、非开放洞窟(320洞窟)和窟外大气中各粒径颗粒物(总悬浮颗粒物TSP、粗颗粒物PM10和细颗粒物PM2.5)背景和典型沙尘天气质量浓度及其碳组分和水溶性无机离子组分含量,获得文物保存环境中大气颗粒物的质量浓度及化学组成。各观测季节内,非沙尘天气窟内TSP质量浓度介于48.4~60.0μg/m3,PM10质量浓度介于13.3~61.3μg/m3,PM2.5质量浓度介于9.9~59.2 μg/m3。洞窟是否向公众开放对窟内颗粒物浓度水平和组成的影响不显著,开放和非开放洞窟颗粒物质量浓度的I/O比值多小于1,显示窟内颗粒物主要源于室外。窟内颗粒物化学组成中,地壳源矿物尘多占据主导地位,在沙尘频发的春季占比介于53.0%至80.7%之间,冬季占比介于17.1%~44.0%。其他化学组分中,细颗粒PM2.5中碳组分和总水溶性无机离子含量占比明显高于TSP和PM10。冬季窟内PM2.5质量浓度低于春季,但碳组分和无机离子浓度值和含量占比均高于春季(除去春季16洞窟),冬季碳组分和无机离子含量占比高达60%,其中酸性组分含量占比和可达30%。对莫高窟大气颗粒物的控制不能忽视细颗粒浓度及其化学组成的潜在危害。  相似文献   
107.
The effectiveness of the multi-mode control of seismically excited building installed with distributed multiple tuned mass dampers (d-MTMDs) is investigated by comparing dynamic response with the other controllers, such as passive friction dampers, semi-active dampers, single tuned mass damper (STMD), and multiple tuned mass dampers (MTMDs-all.top), both installed at the top of the building, and arbitrarily distributed MTMDs (ad-MTMDs). It is concluded that the d-MTMDs exhibit improved performance as compared with the STMD, MTMDs-all.top, and ad-MTMDs. The d-MTMDs are also convenient to install owing to the reduced space requirements, being placed at various floors.  相似文献   
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