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   2917篇
  免费   164篇
  2024年   13篇
  2023年   74篇
  2022年   22篇
  2021年   33篇
  2020年   135篇
  2019年   192篇
  2018年   192篇
  2017年   204篇
  2016年   168篇
  2015年   116篇
  2014年   120篇
  2013年   514篇
  2012年   168篇
  2011年   146篇
  2010年   133篇
  2009年   125篇
  2008年   119篇
  2007年   118篇
  2006年   105篇
  2005年   70篇
  2004年   43篇
  2003年   46篇
  2002年   44篇
  2001年   34篇
  2000年   33篇
  1999年   11篇
  1998年   9篇
  1997年   10篇
  1996年   10篇
  1995年   5篇
  1994年   4篇
  1993年   7篇
  1992年   4篇
  1991年   1篇
  1990年   1篇
  1988年   1篇
  1987年   1篇
  1985年   7篇
  1984年   6篇
  1983年   8篇
  1982年   7篇
  1981年   5篇
  1980年   5篇
  1979年   9篇
  1978年   3篇
排序方式: 共有3081条查询结果,搜索用时 156 毫秒
1.
In 1312, the Swedish dukes Erik and Valdemar Magnusson married the Norwegian princesses Ingeborg Haakonsdaughter and Ingeborg Eriksdaughter at a ceremony in Oslo, Norway. In 1313, the two couples were reunited at a purpose-built banquet hall, believed to have been located in the medieval Swedish town of Lödöse. The main source of information concerning these events is the Swedish medieval rhyme chronicle The Chronicle of Duke Erik. However, a closer reading of the chronicle reveals that Lödöse is never mentioned in relation to the banquet hall. The article discusses the passing down of knowledge through generations of the same professional collective, in this case the professional collective of Swedish historians during the twentieth century, and demonstrates how the validity of once-established prescientific knowledge persists. To achieve its goal, the article applies Ludwik Fleck's terms “thought collective,” “thought style,” and “tenacity in science,” as well as Thomas Kuhn's concept of the “paradigm,” to a historiographical case study of how the proto-idea of the banquet hall being located at Lödöse has survived to become an established scientific fact. The location of the banquet hall concerns but a minor detail in the turbulent political situation of the Swedish kingdom during the first decades of the fourteenth century. However, the continuing reiteration of this minor detail is evidence of a larger phenomenon, namely how contemporary historical research is influenced by scholars in the prescientific past.  相似文献   
2.
Palace lanterns were important and highly visible decorations in the imperial palace in Beijing, China, during the Qing dynasty (1636–1912). Most lanterns had colourful tassels made of fibres. The study performed a comprehensive investigation of the materials and dyes used for palace lantern tassels preserved in The Palace Museum, Beijing. Eight samples with different colours, including yellow, green and red, from five palace lanterns were analysed. By using ultra-performance liquid chromatography combined with time-of-flight mass spectrometry, the compositions of the dyes were identified quickly, and thus the dyes' origins were explored. A X-ray fluorescence spectrometer assisted in the detection of whether a mordant was used during the dyeing process. As a result, the tassels were all made of silk, discovered through the use of microscopic observation and micro-Fourier transform infrared spectrometry analysis. Different dyeing techniques were found in these tassels: yellow tassels were dyed by cork tree or turmeric by a direct dyeing method; greens were dyed by pagoda bud with an iron mordant, or by the combination of cork tree and indigo using multi-dyeing method; and red tassels were coloured with different acid red industrial dyes. These results provide valuable data for the conservation of ancient textile tassels and contribute to the investigation of other hanging tags.  相似文献   
3.
Geographic research on neoliberalism has explored the restructuring of educational landscapes wrought through marketisation of preschool, school and higher-education provision and considered the responsibilisation of parents and children for educational outcomes. This study develops understanding of the contingent emergence of neoliberal educational reform, and its progressive and regressive impacts, through an examination of the burgeoning private tuition market in England and Wales. The paper outlines the contours of the previously hidden supplementary education industry, demonstrating that it reinforces regional and classed inequalities, while opening possibilities for ethnic minority advancement. Conceptually, the paper advances debate about socio-spatial specificity in neoliberal change, showing that the intersection of policy, free markets and consumer behaviour reshapes the educational landscape in ways that extend beyond state intention and control. Through these processes, contingent market forms are produced that offer social mobility for some, but ensure the social reproduction of enduring regimes of power.  相似文献   
4.
The time dimension has not attracted enough attention in policy process research in China, yet speed is the most distinctive feature of China’s recent development. This article, based on observations of China’s policy practices, proposes a new research perspective for understanding how the Chinese government has been able to address policy challenges in an era of rapid transition. The approach adopted by the government allows decision makers to respond quickly to serious problems with a truncated decision-making process, and then implement the decisions through a more gradual deliberative process. The article examines China’s coal-mining industry reform as an empirical case to illustrate how this governance approach has been used to achieve major policy reform, namely property rights reform for coal mines, while simultaneously maintaining stability, regulating production safety, and stimulating industrial development. The article concludes with a discussion of the broad implications of this pattern for improving the effectiveness of public policy both in and outside China.  相似文献   
5.
The concentrations of two major elements and thirteen trace elements in 73 selected sherds of fine grey ware from the Iron Age and Roman period, excavated at Conimbriga, Santa Olaia and Tavarede, Portugal, were determined by instrumental neutron activation analysis. These concentrations were used to calculate distance matrices which were then subjected to cluster analysis employing SAHN and k-means methods, as well as to principal components analysis, to group the sherds according to the overall similarity of their compositional characteristics. The results showed that equivalent groupings appeared regardless of the taxonomic method used. Two major clusters were recognized corresponding to two different sites, namely Conimbriga and Santa Olaia, suggesting that the ceramics from these sites were made locally. No significant differences in compositional patterns were observed between iron age and roman sherds from Conimbriga.  相似文献   
6.
A problem which has arisen in discussions of an elm-disease explanation for the Neolithic elm decline has been the lack of fossil records of Scolytus scolytus (F.) (elm bark beetle), which is the main carrier of the fungus which causes the present epidemic of Dutch Elm Disease. Now, the discovery of wing cases of two individuals from elm decline deposits at Hampstead Heath, London, proves that the beetle was present in Britain during this episode. The deposits in which it occurs are described, and the various implications for elm disease causing, aiding or at least occurring during this stage of the early Neolithic are discussed.  相似文献   
7.
丁晓杰 《史学月刊》2007,(10):73-80
日本树立伪蒙疆政权后,为了掠夺该地区丰富的畜产资源,实行畜产统制政策。羊毛统制是畜产统制的核心,即对绵羊的增产改良、羊毛的收购、对外输出等,实行强制性的政府指导、控制措施。其中,绵羊改良是羊毛统制政策的重点之一。为了获取重要战略资源羊毛,日本将该地域作为大陆绵羊改良的基地,通过伪蒙疆政府、日系企业、蒙古绵羊协会等组织对肉、皮兼用型的蒙古原种绵羊进行改良,实质是为日本的对外侵略扩张提供羊毛这一急需的战略资源。  相似文献   
8.
The presence of DNA has been demonstrated in the cell nuclei of an ancient Egyptian mummy fragment. When extracted, this DNA proved to be degraded to a considerable extent and chemically modified. However, the preservation of nucleic acids in this specimen suggests that applying recombinant DNA techniques to the study of ancient mummified tissues might prove to be a fruitful future area of research.  相似文献   
9.
周滔  张璞洁 《人文地理》2023,38(1):118-129+157
乡村振兴要求走乡村内生性发展道路,客观认知乡村发展能力的时空分异格局和交互关系对乡村振兴战略实施具有重要意义。本文从农业产业发展、农村基础建设和农民社会生活三个维度构建测度指标体系,并引入面板向量自回归模型识别影响乡村发展能力的敏感因素,以此测度乡村发展能力指数,进而采用探索性时空数据分析方法揭示乡村发展能力的时空交互特征。结果表明:(1)我国中部地区多维乡村发展能力提升,但呈明显的空间异质性,不同维度间差异化显著;(2)中部地区多维乡村发展能力局域空间格局呈现较强的动态性并整体表现出较强的空间依赖关系;(3)邻接地级市多维乡村发展能力的时空交互网络以正向关联为主,局部空间呈差异化的竞合态势。  相似文献   
10.
As science becomes an increasingly crucial resource for addressing complex challenges in society, extensive demands are placed upon the researchers who produce it. Creating valuable expert knowledge that intervenes in policy or practice requires knowledge brokers to facilitate interactions at the boundary between research and policy. Yet, existing research lacks a compelling account of the ways in which brokerage is performed to gain credibility. Drawing on mixed‐method analysis of 12 policy research settings, I outline a novel set of strategies for attaining symbolic power, whereby policy experts position themselves and others via conceptual distances drawn between the “world of ideas” and the “world of policy and practice.” Disciplinary distance works to situate research as either disciplinary or undisciplinary, epistemic distance creates a boundary between complex specialist research and direct digestible outputs, temporal distance represents the separation of slow rigorous research and agile responsive analysis, and economic distance situates research as either pure and intrinsic or marketable and fundable. I develop a theoretical account that unpacks the boundaries between research communities and shows how these boundaries permit policy research actors to achieve various strategic aims.  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