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81.
为了探讨文物岩石材料劣化结垢病害的特征和形成机理,以洛阳龙门石窟和北京西黄寺清净化城塔塔基砂岩条石为研究对象,采用全岩化学全分析和X射线衍射测试技术对两类结垢物质的成分和形成过程进行了系统分析和研究。研究结果表明,龙门石窟的结垢物是在水长期渗漏过程中对碳酸盐岩溶蚀改造沉淀后而形成的;而西黄寺清净化城塔塔基砂岩条石上的结垢物来源于砌筑砂浆(其主要物质成分为方解石),白色结垢物的形成机理为,砌缝砂浆在水渗流作用下发生溶蚀,溶蚀形成的溶液流至其下砂岩条石上经沉淀及重结晶形成结垢物。  相似文献   
82.
This paper presents results of the use-wear analysis of Chalcolithic copper-base metalwork from the Italian peninsula. Previous research led to contrasting scholarly opinions regarding the function of early metal axes, daggers and halberds from this region. Whilst some authors interpreted these objects as utilitarian tools and weapons, others saw them as symbolic signifiers of social status and personhood. The analysis conducted here shows that this is a false dichotomy as all classes of metalwork seem to embody to some extent both utilitarian and non-utilitarian values. In particular, axes were primarily used for woodworking and other practical tasks, but were mostly withdrawn from circulation when still usable. This suggests that deposition practices bore a loose relationship, if any, with the functional value of the tools. Daggers were employed in a range of symbolically charged practices that left little wear on cutting edges. These probably included the sacrificial slaughtering and skinning of large animals such as cattle and horses. Halberds were utilised as weapons in champion’s duels in which display of combative skills and prowess would have been far more important than killing the opponent. This explains the relatively low rate of damaged blades in the record. Regardless of their practical function in lifetime settings, these objects were all similarly employed in burial to reproduce core social values such as gender and age. Importantly, this study contributes to debunking undemonstrated assumptions concerning the function of early metalwork in European prehistory. It also defines a replicable analytical protocol for the use-wear analysis of ancient copper-alloy artefacts.  相似文献   
83.
The conservation of historic stone buildings and sculptures is recently receiving growing attention and becoming a focus of research because of rapid changes in weather conditions (pollution, acid rain, etc.). Presently, techniques for stone conservation primarily involve the use of organic coating treatments, but their side effects have been recognized. In contrast, some traditional materials used in historic stone buildings function well for thousands of years. In this paper, we report our research on the reasons why traditional protective materials can provide an unexpected long-term protection. First, calcium carbonate was prepared according to a formula for making Chinese traditional consolidating materials, and its structure and morphology were examined by different instruments. Second, the reinforcing effectiveness of the prepared CaCO3 powders was tested and analyzed by investigating its surface characteristics. The experimental results reveal that a biocontrolled process occurs, in which an organic template can induce the precipitation of a mineral structure, which in turn results in a great improvement in the conservation of the historic stone buildings protected by these traditional protective materials. This provides a contribution toward the development of new researches on biocontrolled processes and on some protective materials with excellent performance through biocontrolled synthesis.  相似文献   
84.
2003年底,湖北省恩施自治州博物馆考古队对巴东县张家坟墓群进行发掘,发现古墓3座,其中M1墓道出土有一块石板,上刻有136字,内容十分重要。《巴东县张家坟墓群2003年发掘简报》(下称《简报》)进行了介绍并录有释文[1]。《中国书法》2010年第4期刊有该刻石彩色照片,并附有陆  相似文献   
85.
It has been suggested that between 80 and 35 ka the Middle Stone Age record of South Africa reveals episodes of inventiveness and innovation, punctuated by apparent returns to more conventional technologies. One such episode is the Howiesons Poort (HP). The appearance of a range of small geometric forms, apparently used as insets in multi-component tools, has been considered as evidence of improved hunting weapons, with possible social and symbolic connotations. On the basis of evidence such as backed tool production, small blade technology, the occurrence of typical end-scrapers and burins similar to those encountered in the European Upper Paleolithic, long-distance transport of fine-grained raw materials, and non-lithic novelties, the HP is associated with increased levels of technological efficiency and with behavioral innovations that could have allowed the expansion of African populations to other regions. Yet our knowledge of HP technology and tool production is limited to the analysis of Klasies River Main site by Singer and Wymer and Sarah Wurz, and a few preliminary reports from other sites. This is why we present here a detailed technological and typological analysis of several HP and post-HP assemblages from the well-excavated, well-dated and well-stratified site of Rose Cottage. Our analysis shows: (a) that the HP blade production was a real technical innovation, but was not based on indirect percussion, as often suggested; (b) that blade production was based on the use of marginal percussion which does not occur in the blade production of the Eurasian Middle Paleolithic; (c) that the tool kit was dominated by backed pieces, but not all can be considered as hunting weapons; (d) that neither end-scrapers nor burins are typical of this industry and are no more an antecedent to the European Upper Paleolithic than the end-scrapers and burins of the Middle Paleolithic; (e) that patterns of raw material procurement do not conform to models based on evidence from Klasies; (f) that diachronic changes within the Rose Cottage sequence indicate slow, gradual abandonment of the technological style of the HP; (g) that the post-HP assemblages are of MSA character and are typologically and technologically quite similar to the European Middle Paleolithic; (h) that the lack of persistence of the HP innovations is in need of an explanation. The HP is not a monolithic entity. Implications for the symbolic interpretations of the HP phenomenon are discussed.  相似文献   
86.
以新兴的网络传播手段——博客作为切入点,分析了海外华人新移民博客社区的种类和组织形态;阐述了海外华人新移民通过博客与中国社会互动的意义、方式及影响。通过博客这一新的互动工具和平台,海外新移民可更加直接而生动地了解中国变化,了解中国人的最新思维、心态和社会变迁;拓宽自身更大的社会交往空间、话语渠道、传播途径和社会影响;与中国原住地的原有关系保持思想上的无边界的联系,甚至参与中国的改变进程。  相似文献   
87.
Since the initial ‘discovery’ and explanation of the Soanian industry by H. de Terra and T.T. Paterson in the 1930s, multiple interpretations have been offered by various investigators on its chronology, geographical distribution, relationship with the Acheulian, and technological progression. In most cases, the presence of explicit tool-types and the absence of Acheulian bifaces were the distinguishing features utilized to recognize the industry as well as delineate its technological development through time and space. However, in light of recent intra-regional geoarchaeological investigations and the analyses of a large surface assemblage by the author, the existing framework for Soanian typology is in need of judicious revision. In this paper, some of the methodological and interpretative problems are briefly discussed from a historical perspective and the technological organization of cores and core-based tools from Toka, a rich factory site, is described. Essentially, the Toka assemblage comprises a dynamic range of non-biface tool-types on quartzite, which possess varying patterns of core reduction techniques, edge retouch, and associated use-wear. The study also introduces a modified typological classification of specific chopper morphologies, which may be broadly applicable in global context.  相似文献   
88.
An experimental approach was used to determine how stone tool materials affect the frequency of observed cutmarks. Five whitetail deer were butchered by an expert butcher using flint and obsidian tools and the skeletons were prepared and analyzed. The authors found that the deer butchered with obsidian tools generally displayed fewer incidents of cutmarks than their flint-butchered counterparts. Consideration of this variable may prove to be important to archaeologists attempting to answer questions of specialization or when making comparisons of cutmark data between sites.  相似文献   
89.
ABSTRACT

Considerable change occurred in the Late Holocene Later Stone Age of Namaqualand, northwestern South Africa. Focusing on stone artifacts, pottery, and ostrich eggshell beads, the cultural sequence for the area is described. Two additions are identified, complicating the traditional model for the introduction of herding into the country. From the mid-Holocene onward, lithic assemblages are based on milky and/or clear quartz and cryptocrystalline silica and initially contain many backed tools with scrapers more common during the first millennium BC. These are hunter-gatherer assemblages. During the final centuries BC, backed bladelet-rich assemblages based on clear quartz appear, with the earliest examples demonstrating typological continuity with the existing assemblages. About 1,500 years ago, expedient assemblages lacking retouch and based on poorer quality quartz appear. The three types co-occur during the last 1,500 years, occasionally in combination with one another. This contrasts strongly with other parts of South Africa where just two distinct assemblage types are identified, suggesting that the hunter-gatherer-herder dichotomy is not universally valid. The artifact patterns between about 200 cal BC and cal AD 500 and the introduction of livestock suggest considerable cultural and social change, heralding the onset of a local Neolithic, but the exact mechanisms remain unclear.  相似文献   
90.
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