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71.
72.
欧洲文物保护标准化技术委员会(欧盟文标委)是欧洲标准委员会(CEN)下设的一个专业技术委员会,目的是为欧洲地区制定一个协调统一的文物保护方法体系,同时为欧洲各国文物保护的科学化和规范化提供技术保障。欧盟文标委由5个专家组组成,分别开展15个类别的文物保护标准的起草工作,并与相关国际组织积极合作,其标准的制定过程科学规范,工作程序严谨,标准内容符合时代发展的需求,为世界各国的文物保护行业提供了典范。  相似文献   
73.
The Knowledge of Debt: Law, Media Technique, and Everyday Experience in Liberal Capitalism. Performing an object such as ‘the economy’ hinges on practices of formatting knowledge. The article proposes to look at such instituting moments in connection with social conflicts over the legitimate rules of exchange. This is exemplified by way of recounting the story of the codification of Swiss bankruptcy law in 1889. In order to homogenize the legal procedures of debt collection and bankruptcy, two subject categories were instituted: ‘merchants’ and ‘non-merchants’. These different categories were thought to account for the diverging temporalities and spaces of credit exchange in everyday economic life. The introduction of the commercial register, a media-technical apparatus, enabled a formal distinction between ‘merchants’ and ‘non-merchants’. However, this boundary was contested and proved to be porose.  相似文献   
74.
Luminescence dating techniques have been used extensively for archaeological and geological samples. Such techniques are based on thermally or optically stimulated signals. This paper presents simulations of several luminescence techniques for equivalent dose (ED) estimation for ceramic materials containing quartz. The simulations are carried out using a recently published comprehensive kinetic model for quartz, consisting of 11 electron and hole traps and centers. The complete sequence of the experimental protocols for several thermoluminescence (TL) and optically stimulated luminescence (OSL) techniques are simulated using the same set of kinetic parameters. The specific simulated protocols are: additive dose TL protocol, predose technique (both additive and multiple activation versions), phototransfer protocol, single aliquot regenerative optically stimulated luminescence (SAR-OSL) protocol, and SAR thermoluminescence protocol (SAR-TL). One hundred random variants of the natural samples were generated by keeping the transition probabilities between energy levels fixed, while allowing simultaneous random variations of the concentrations of the 11 energy levels. The relative intrinsic accuracy and precision of the protocols are simulated by calculating the equivalent dose (ED) within the model, for a given natural burial dose of the sample. The intrinsic accuracy of these techniques is estimated by simulating natural irradiation of the samples with a known burial dose, followed by simulation of the luminescence method used to recover the estimated dose ED. The percent difference between the burial dose and the ED value represents the simulated accuracy of the luminescence technique. The relative intrinsic precision of these techniques is estimated by fitting Gaussian probability functions to the ED values obtained with the 100 model variants. It is found that the various techniques can reproduce natural paleodoses in the range 10 mGy–10 Gy with a typical intrinsic accuracy of +1 to 10%. Techniques based on single aliquot protocols were found in general to be more precise than techniques requiring the use of multiple aliquots. In addition, techniques based on interpolation of experimental data were found to be consistently both more precise and accurate than those based on extrapolation of experimental data.  相似文献   
75.
中国古书画源远流长,在长期的收藏和传承历史中会出现各种各样的病害,传统书画修复技术因此得到发展。在书画修复中,观察和分析作品的病害情况是制定修复计划的重要前提,但保护修复中发生的脱色现象是后出现的二次病害,在修复计划中易被忽略以致画心被破坏,失去色泽变得暗淡,甚至出现部分内容缺失,对书画伤害极大,故而对修复中的二次脱色现象进行研究并优化相关修复技术是至关重要的。本工作以实践经验为基础,对古书画修复中的二次脱色现象进行全面的阐述和研究,从材料和工艺的角度分析了病害成因,将常见的修复中人为造成的脱色现象进行了分类,提出了修复中二次脱色现象发生的预防判断标准,优化了修复技术,为古书画病害的研究、书画修复技术的优化提供参考。  相似文献   
76.
利用热释光测定年代技术对青龙镇出土样品的烧造年代进行检测分析,以求帮助了解不同历史时期青龙镇瓷器贸易的发展状况。为此,本工作以青龙镇遗址出土瓷器中的67件瓷片及4件砖瓦样品为研究对象,用热释光前剂量饱和指数法测定瓷片样品古剂量;用热释光高温细颗粒技术测定砖瓦样品古剂量;用厚源α粒子计数法和X射线荧光光谱技术测量样品年剂量。瓷片样品热释光年代结果从唐代至南宋不等,砖瓦样品年代结果为北宋时期烧造,与文献记载中隆平寺塔的始建时间相符。  相似文献   
77.
近年来的分析与研究表明,海洋出水沉船的木材中普遍存在大量的以Fe S2和Fe S为代表的硫铁化合物难溶盐,它们在空气中和一定湿度条件下,会氧化生成硫酸,使木材纤维素发生快速降解,从而对木船造成毁灭性的破坏。目前,硫铁化合物的脱除仍然是世界性难题,很多国家发现的木质沉船都面临这方面的困扰。为此,本研究以宁波象山"小白礁I号"清代沉船遗址出水的船体木材构件为研究对象,研发了金属络合剂与氧化剂复配材料EDTAHO,开展了海洋出水木材中沉积的二硫化亚铁的去除技术初步研究,取得了良好的保护效果。本研究结果可为后续脱水定型和加固修复打下良好的基础,有利于海洋出水木质船体的长期保存。  相似文献   
78.
蒋刚 《江汉考古》2005,1977(4):59-68
本文对重庆、鄂西地区出土商周时期甲骨钻凿形态做了类型学分析,并与其周边地区甲骨做了比较研究,探讨了该地区在占卜上的地方特色,从而区别出了中原地区与长江流域两种不同的占卜传统.  相似文献   
79.
A new interpretation of early stone-tool use by hominins at Olduvai depicts them as involved in battering activities (using pounding tools) rather than making cutting butchering tools as is commonly inferred in most other Plio-Pleistocene sites where lithics appear associated to faunal remains. The bulk of this interpretation is based on the recognition of the stigma of percussion activities in anvils and detached by-products. Renewed excavations at BK after more than half a century of the beginning of the digging at the site by M. Leakey have produced a new and unbiased lithic assemblage. The taphonomic study of the faunal assemblage has shown that BK is an anthropogenic site where carcass butchery practices were repeatedly performed over a vast amount of time. The present analysis of the lithic artefacts supports this interpretation by showing that the obtainment of flakes was the principal aim in stone knapping. We argue that a number of technical traits observed in the lithic collection of BK can be best interpreted as the result of bipolar loading rather than the by-products of battering activities. Since BK has provided the second largest collection of hominid-modified bones from Olduvai, it is concluded that detached pieces produced in the course of bipolar reduction might have played an active role in bone modification and that active rather than passive percussion behaviors might have been responsible for the formation of the lithic assemblage. The functionality of the Oldowan stone tools are discussed under the light of the new study.  相似文献   
80.
新石器时期中原地区谷物加工技术初探   总被引:1,自引:0,他引:1  
本文从考古发现的石磨盘、石磨棒中的石磨棒的形制入手,讨论了石磨棒的使用方式,指出滚压是史前粟脱壳加工的有效方式,揭示了中国先民7000年前就已经熟练运用滚压技术的事实。  相似文献   
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