首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   4197篇
  免费   155篇
  2023年   27篇
  2020年   57篇
  2019年   68篇
  2018年   129篇
  2017年   119篇
  2016年   150篇
  2015年   100篇
  2014年   102篇
  2013年   1158篇
  2012年   118篇
  2011年   140篇
  2010年   122篇
  2009年   100篇
  2008年   104篇
  2007年   67篇
  2006年   64篇
  2005年   63篇
  2004年   58篇
  2003年   32篇
  2002年   40篇
  2001年   61篇
  2000年   51篇
  1999年   57篇
  1998年   38篇
  1997年   43篇
  1996年   43篇
  1995年   33篇
  1994年   38篇
  1993年   44篇
  1992年   45篇
  1991年   35篇
  1990年   29篇
  1989年   36篇
  1988年   35篇
  1987年   46篇
  1986年   35篇
  1985年   50篇
  1984年   38篇
  1983年   65篇
  1982年   49篇
  1981年   56篇
  1980年   54篇
  1979年   38篇
  1978年   40篇
  1977年   59篇
  1976年   42篇
  1975年   44篇
  1974年   32篇
  1973年   30篇
  1971年   33篇
排序方式: 共有4352条查询结果,搜索用时 31 毫秒
81.
82.
The article addresses some of the problems arising from the publication of a recent numismatic catalogue including coins from all parts of the Islamic world. The problems concern in particular the coins of the medieval Yemen and the article comprises a critique of those coins listed under the Arabian peninsula and the Yemen.
Catalogue nos. 101 and 104 are dealt with in some detail since they are erroneously ascribed to mints in Mecca and Minā, respectively. The former is struck in the name of a Zaydī imam, the latter is Rasulid and labelled as having been struck "for a special occasion". The intriguing question of the mysterious Ayyubid prince, al-'Ādil Abū Bakr, arises too (nos. 125 etc.), although no definitive answer can yet be suggested. Much more information is now available on the striking of coins in Tha'bāt during Rasulid times. A number of other points bearing on the numismatics, the history, and the geography of the medieval Yemen are discussed in the article.  相似文献   
83.
The reasons why the Western Mediterranean, especially Carthage and Rome, resisted monetization relative to the Eastern Mediterranean are still unclear. We address this question by combining lead (Pb) and silver (Ag) isotope abundances in silver coinage from the Aegean, Magna Graecia, Carthage and Roman Republic. The clear relationships observed between 109Ag/107Ag and 208Pb/206Pb reflect the mixing of silver ores or silver objects with Pb metal used for cupellation. The combined analysis of Ag and Pb isotopes reveals important information about the technology of smelting. The Greek world extracted Ag and Pb from associated ores, whereas, on the Iberian Peninsula, Carthaginians and Republican‐era Romans applied Phoenician cupellation techniques and added exotic Pb to Pb‐poor Ag ores. Massive Ag recupellation is observed in Rome during the Second Punic War. After defeating the Carthaginians and the Macedonians in the late second century bce , the Romans brought together the efficient, millennium‐old techniques of silver extraction of the Phoenicians, who considered this metal a simple commodity, with the monetization of the economy introduced by the Greeks.  相似文献   
84.
85.
The standard theory of optimal jurisdictional size hinges on the existence of economies of scale in the provision of local public goods and services. However, despite its relevance for forced local amalgamation programs and related policies, the empirical evidence on the existence of such economies of scale remains elusive. The main goal of this paper is to produce an updated and comprehensive quantitative review of the existence of economies of scale in the provision of local public goods using a meta-analysis approach to systematize the wide range of empirical approaches and modeling frameworks found in the previous literature. Our analysis confirms the presence of moderately increasing to constant returns to scale in the provision of local services with no reduction in the average costs of production in the delivery of most local public services beyond a certain, modest jurisdictional size, which many studies have estimated at 10,000 residents. Also, the potential for economies of scale differs at least across three traditional services: education, water and sanitation, and garbage collection, being highest for education and lowest for garbage collection. Our analysis also offers guidelines for future empirical research in this area. Physical output and production cost data should be used, together with translog specifications for the modeling of cost functions. Last, we find evidence that the determinants of output cost elasticity include bidirectional publication bias and population density but do not include the presence or absence of modern “lean” production technologies or the (perceived) capital intensity of the sector, contrary to conventional wisdom. These findings have significant policy implications for countries considering jurisdictional consolidation programs.  相似文献   
86.
This paper analyses social transformations in the Early Iron Age based on a holistic and longue durée approach applied to the first fortified habitats in the Iberian north-west. Through a comprehensive review of two paradigmatic settlements of the EIA in the province of A Coruña (Galicia, north-west Iberia), Punta de Muros and A Graña, a comparison is drawn between the social and territorial dynamics of this period by means of an in-depth analysis of the main characteristics of both settlements. Accordingly, a greater level of social complexity during the phases of occupation of the settlement of Punta de Muros has been identified, in contrast to the resistance to change observed in A Graña. Based on these conclusions, the role of metalworking and its symbolic value in fostering and legitimizing these social and territorial transformations and in the development of Iron Age communities are analysed.  相似文献   
87.
This guest editorial reflects on the relevance of anthropology for extinction concerns, a rapidly expanding practical, ethnographic and theoretical space at a time of impending mass extinction. While biological extinction is necessarily a multispecies development (usually implicating humans), traditional species talk – focused on taxonomies, collections and classification – needs critical rethinking as it necessarily diverts attention from the vitality of life. The broad discipline of anthropology has much to offer for understanding processes of extinction and recovery, fleshing out habitat problems and prospects of extinction, and advancing meaningful environmentalist practices.  相似文献   
88.
Publications and organizational developments relating to the history of archaeology from 1989 until June 1993 are critically examined. Attention is paid to the changing motivations for producing such publications, their shifting intellectual orientation, controversies, especially as they relate to internal vs external approaches and the epistemological status of explanations, problems of verification, and the status of these studies as a subfield within archaeology.  相似文献   
89.
Discriminant analyses of distances and angles obtained from 25 coins struck by P. Crepusius in 82 BC permitted the correct chronology for five groups of closely-related dies to be obtained by the method of Carter and Frurip. Twenty distances and 15 angles were measured on 10 x projections of the coins which represented five groups of dies separated in time from each other. The use of all or many variables gave poorer results than the use of five to ten variables having a high ‘figure of merit’, defined as the maximum range of mean values for a given variable in the five groups of dies divided by the mean standard deviation of the variable in the five groups. It is recommended that chronologies of ancient coins be determined from Mahalanobis distances by using only variables of relatively high figure of merit.  相似文献   
90.
Limestone from quarries known to medieval craftsmen and from the monuments they built and embellished, as well as from carvings now in museum collections, has been characterized by neutron activation analysis. Specimens from 38 quarries in the Lutetian and Jurassic limestone formations of France and from sculptures in American and French museums have been tested, and the results have been compiled in a data base to which art historians may refer when attempting to determine provenance for sculptures. Multivariate statistical analysis of concentration data shows stone from a particular quarry in the Paris basin to be compositionally homogeneous and distinguishable from other quarries in the same formation. The same approach to data related to quarries near the Burgundian abbey of Cluny finds general agreement between classifications based on compositional and on petrographic data, but the number of samples available for analysis at the time of writing was insufficient to achieve the finer distinctions reported for the Paris basin.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号