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1.
高颐阙是东汉晚期的红色砂岩的建筑物。位于四川省雅安市。阙檐东面残缺.导致日晒雨淋加剧,苔藓丛生,从而引起严重风化。为此,对残损阙檐进行了修复。根据高颐阙的结构.雅安市的气候特征及阙石的化学组成和物理性质.讨论了薄片检查和 X 衍射分析的结果、修复残缺阙檐的理论基础以及计算、修复的程序和效果。  相似文献   
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We use trace element discrimination diagrams to provide a geochemical fingerprint for Tufo Lionato, the volcanic rock most commonly used in the ancient Roman dimension stone technique. Based on the comparison of their geochemical signatures, we identify different rock facies of Tufo Lionato employed since the fourth to third centuries and through the second century bce in the construction of the temples of the Area Sacra di Largo Argentina. These rock facies correspond to two previously identified building stones: Aniene Tuff and Monteverde Tuff, named after their supposed source areas located in the Aniene River Valley and in the homonymous locality of the Tiber River Valley, respectively. However, the results of our study demonstrate previous misidentification of these volcanic rocks in the different construction phases of Temple C, providing a revision of the dating system currently accepted for the diffusion of Tufo Lionato architecture. We show that the Aniene facies has been exploited since the end of the fourth century bce and that it was employed along with Tufo Giallo della Via Tiberina in the podium and staircase of Temple C, whereas observations at Largo Argentina suggest that the ‘Monteverde Tuff’ was only sporadically used in the early phases of the dimension stone construction technique.  相似文献   
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Palaeohistology as a valuable diagnostic instrument is dependent on the production of high‐quality thin‐ground sections from dry bone. The objective of this study was to consider technical differences and assess the qualitative outcomes of five techniques for preparing thin‐ground sections from dry archaeological bone. Established techniques with long follow‐up times and excellently documented results were compared with simpler and cheaper time‐saving techniques. Evaluations were made of the quality of thin sections obtained by one classical machine‐based embedding technique, two revised versions of the same technique, one manual moulding technique based on Frost's rapid technique and one manual hybrid technique. Five osteological specimens of differing quality were prepared following the manuals for these five techniques and examined microscopically with respect to a list of standardised histological and diagenetic parameters. Alterations in the specimens attributable to preparation effects were recorded, and observations were scored with reference to three criteria: section quality, technical quality and staining. The results show that embedding techniques are to prefer. Superglue should not be used as a mounting or embedding medium. Manual grinding comes with several limitations, and machine cutting and grinding are preferred. Haematoxylin staining can be successfully applied to embedded specimens, giving more information on microscopic diagenetic processes. A stepwise manual for a revision of the classical embedding technique is presented. The time required for producing sections using classical embedding techniques is shortened from 6 weeks to 3.7 days by refining the preparation/polymerization processes involved with no loss of osteological data. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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考古出土实物研究表明,商周青铜器铭文制作,通常是先雕刻正阴字铭文模,然后翻制反阳字铭文活块泥芯,镶嵌于主体泥芯合适位置组成复合泥芯,最后在浇铸青铜器时一并铸成于器物内壁上。复制具有151字铭文的西周晚期青铜颂鼎,整体采用失蜡铸造工艺,铭文制作借鉴商周青铜器陶范铸造的相关工艺,多次翻制制作一块铭文蜡片,嵌入模具型腔后翻制整体硅橡胶泥芯,获得了理想的效果。  相似文献   
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商前期青铜斝的制模工艺初步研究   总被引:1,自引:0,他引:1  
制模是青铜铸造工艺的第一道工序,也是关键工艺之一,其重要性不言而喻。而文献记载的缺乏,考古实物资料的限制,严重影响了学界对陶模制作工艺的认识。近年来,我们通过对大量青铜实物的细致考察,发现大多青铜器上都有明确、整齐的范缝。为研究夏商之际的范铸技术,我们对商前期青铜斝进行了模拟制备,发现分型制模才是其制模工艺的主流,用此种工艺制模更加符合器物上的范铸特征。  相似文献   
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前剂量饱和指数法测定瓷器的热释光年代   总被引:2,自引:2,他引:0  
用前剂量饱和指数法测定39件历代瓷器的热释光年代。结果表明,热释光年代与考古年代在一个标准偏差(±1σ)为29%以内的一致性非常良好。这样的误差在瓷器年代测定中是可以接受的。  相似文献   
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The quantitative assessment of COH fluids is crucial in modeling geological processes. The composition of fluids, and in particular their H2O/CO2 ratio, can influence the melting temperatures, the location of hydration or carbonation reactions, and the solute transport capability in several rock systems. In the scientific literature, COH fluids speciation has been generally assumed on the basis of thermodynamic calculations using equations of state of simple H2O–nonpolar gas systems (e.g., H2O–CO2–CH4). Only few authors dealt with the experimental determination of high‐pressure COH fluid species at different conditions, using diverse experimental and analytical approaches (e.g., piston cylinder + capsule piercing + gas chromatography/mass spectrometry; cold seal + silica glass capsules + Raman). In this contribution, we present a new methodology for the synthesis and the analysis of COH fluids in experimental capsules, which allows the quantitative determination of volatiles in the fluid by means of a capsule‐piercing device connected to a quadrupole mass spectrometer. COH fluids are synthesized starting from oxalic acid dihydrate at = amb and = 250°C in single capsules heated in a furnace, and at = 1 GPa and = 800°C using a piston‐cylinder apparatus and the double‐capsule technique to control the redox conditions employing the rhenium–rhenium oxide oxygen buffer. A quantitative analysis of H2O, CO2, CH4, CO, H2, O2, and N2 along with associated statistical errors is obtained by linear regression of the m/z data of the sample and of standard gas mixtures of known composition. The estimated uncertainties are typically <1% for H2O and CO2, and <5% for CO. Our results suggest that the COH fluid speciation is preserved during and after quench, as the experimental data closely mimic the thermodynamic model both in terms of bulk composition and fluid speciation.  相似文献   
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随着旅游市场竞争日趋激烈,目的地定位的重要性愈加突出。然而,国内研究和实践对"把握旅游者兴趣和需求"这一定位首要工作普遍认识不足,且实施不到位。鉴于此,本研究对目的地定位中"击中消费者心灵"这一关键环节的实施从理论和实证上进行了阐释。理论上,分析了目的地突出属性与定位之间的关系及当前国内误区。实证上,引入轮换方格分析法,以国内十大海滨城市目的地为要素,阐释了识别旅游者对竞争目的地相比较的目的地突出属性的方法程序。此外,对旅游者访谈结果与目的地业界代表访谈结果的比较发现,供需双方在旅游者需求的认识上不吻合。文章最后还对本研究的应用价值和局限做了总结。  相似文献   
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