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   1032篇
  免费   21篇
  2024年   1篇
  2023年   13篇
  2022年   16篇
  2021年   12篇
  2020年   40篇
  2019年   13篇
  2018年   24篇
  2017年   19篇
  2016年   26篇
  2015年   20篇
  2014年   19篇
  2013年   69篇
  2012年   63篇
  2011年   95篇
  2010年   83篇
  2009年   110篇
  2008年   77篇
  2007年   68篇
  2006年   80篇
  2005年   51篇
  2004年   16篇
  2003年   22篇
  2002年   22篇
  2001年   26篇
  2000年   25篇
  1999年   9篇
  1998年   13篇
  1997年   3篇
  1996年   1篇
  1995年   2篇
  1994年   2篇
  1993年   3篇
  1992年   4篇
  1991年   2篇
  1990年   2篇
  1980年   2篇
排序方式: 共有1053条查询结果,搜索用时 250 毫秒
1.
刘扬 《丝绸之路》2009,(24):43-45
旅游能否成为一门独立学科,关键取决于能否形成一套完善的学科基础理论和方法论。本文分析了中外旅游研究方法的进展情况,对理论实证方法的优越性进行了阐释,将其在国内外旅游研究中不同应用程度作以比较,进而总结出国内旅游研究方法的方向。  相似文献   
2.
3.
Non‐invasive materials characterisation of reconstructed statues of Emperor Qin Shihuang's Terracotta Army has revealed distinct micro‐geochemical patterning within the clay paste used in their manufacture. The significance of this is explored in terms of the production sequence, logistics and supply‐chain management involved in the construction of this enormous funerary assemblage. Of particular interest is a compositional distinction between figures marked with the names ‘Gong’ (宫) and ‘Xianyang’ (咸阳). These seem to represent the products of two workshops involved in the supply of ceramic objects for this ambitious, large‐scale building project undertaken by the Qin Empire during the third century bce .  相似文献   
4.
“窜三苗于三危”的考古学研究   总被引:2,自引:0,他引:2  
本文依据考古学的发现和研究,重新探讨古史传说中的“窜三苗于三危”。为这一传说提供了一种考古学依据。  相似文献   
5.
J. Henderson  J. An  H. Ma 《Archaeometry》2018,60(1):88-104
This paper provides a new review of archaeometric research carried out on glass found in China, set in an archaeological context, from its earliest occurrence to the Song dynasty. It is set within a broad geographical context taking the terrestrial and maritime Silk Road contacts into account. We discuss chemical and isotopic compositional contrasts in glasses from different periods found in different parts of China, the glasses that were almost certainly made in China and those that were imported. A theme that runs through the paper is the problem of provenancing glass found in China, along with a lack of evidence for primary glass‐making sites and minimal evidence for secondary glass production. We discuss the glass artefacts that are of typical Chinese types and contrast these with imports; the structure reflects this contrast. We discuss potential new scientific and archaeological approaches to Chinese glass.  相似文献   
6.
Pan, Z., Zhu, M., Zhu, Y. &; Jia, L., August 2017. A new antiarch placoderm from the Emsian (Early Devonian) of Wuding, Yunnan, China. Alcheringa 42, 10–21. ISSN 0311-5518.

Wufengshania magniforaminis, a new genus and species of the Euantiarcha (Placodermi: Antiarcha), is described from the late Emsian (Early Devonian) of Wuding, Yunnan, southwestern China. The referred specimens were three-dimensionally preserved in black shales, allowing a high-resolution computed tomography reconstruction of anatomical details. The new euantiarch is characterized by a large orbital fenestra, an arched exoskeletal band around the orbital fenestra and a developed obtected nuchal area of the skull roof. Maximum parsimony analysis, using a revised data-set of antiarchs with 44 taxa and 66 characters, resolves Wufengshania gen. nov. as a member of the Bothriolepididae, which is characterized by the presence of the infraorbital sensory canal diverging on the lateral plate, and the nuchal plate with orbital facets. New analysis supports a sister group relationship between Dianolepis and the Bothriolepididae. Luquanolepis, a coeval euantiarch from the neighboring site of the new form, is referred to the Asterolepidoidei and represents the basalmost and earliest member of the Asterolepidoidei.

Zhaohui Pan* [], Min Zhu* [], You’an Zhu? [] and Liantao Jia [] Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, PO Box 643, Beijing 100044, PR China. *Also affiliated with University of Chinese Academy of Sciences, Beijing, 100049, PR China. ?Also affiliated with Uppsala University, PO Box 256, 751 05 Uppsala, Sweden.  相似文献   
7.
杨天石 《近代史研究》2015,(2):53-66,160
美国长期大量向日本出售钢铁、石油等战略物资,助长其侵华实力。1939年7月,蒋介石致电罗斯福,建议美国采取办法,削弱日本的战斗力与经济力。同月,美国政府宣布废止美日商约,对日实行经济制裁。1941年4月,日本向美国提出《日美谅解案》,企图通过谈判,减轻美国对日本的经济压力。罗斯福为避免美国过早陷入大西洋和太平洋同时两面作战的不利局面,提出退让、妥协方案,企图在一定时间内放松对日本的经济封锁。蒋介石坚决反对美国政府改变对日政策,愤而以"国际信义"与"人类道德"相责,胡适、宋子文也积极与美方交涉,最终,美国对日政策由有限度的妥协恢复为全面强硬,美日谈判破裂。日本指责美国已彻头彻尾地成为蒋介石的代言人,于12月初突袭珍珠港等地,太平洋战争爆发。  相似文献   
8.
This article aims at presenting and discussing the strategies for updating the finite element numerical modeling of stone masonry arch bridges using operational modal analysis. The study comprehended three bridges: two old ones, the St. Lázaro and the Lagoncinha bridges, and a recently constructed bridge in Vila Fria, Portugal. Updating of the bridge models is performed by comparing the numerical and experimental modal parameters. Three-dimensional detailed numerical models are used to perform modal analysis of the bridges. Experimental modal identification of the bridges is based on the measurement of their acceleration responses during normal operation. The assigned material properties are also based on available results obtained from in situ and laboratory tests and on the results of visual inspection and historical research carried out for both old bridges.  相似文献   
9.
黄洋 《东南文化》2015,(2):13-18,127,128
考古工作为考古遗址博物馆提供藏品、展品和丰富的考古信息,而考古遗址博物馆是进行考古宣传与教育的重要阵地。在考古遗址博物馆中,为了更好地展示并传播考古信息,考古人应改变以往的工作方式,树立展示传播的意识,不是"窄播"意识,而是"广播"意识,并非只考虑将考古成果"窄播"给考古圈内的学者,也要"广播"给博物馆展览策划师、广大公众;而且考古人应该从田野考古、发掘报告、科学研究三个方面为考古遗址博物馆提供强有力的支撑。  相似文献   
10.
This article introduces latent trajectory models (LTMs), an approach often employed in social sciences to handle longitudinal data, to the arena of GIScience, particularly space‐time analysis. Using the space‐time data collected at county level for the whole United States through webpage search on the keyword “climate change,” we show that LTMs, when combined with eigenvector filtering of spatial dependence in data, are very useful in unveiling temporal trends hidden in such data: the webpage‐data derived popularity measure for climate change has been increasing from December 2011 to March 2013, but the increase rate has been slowing down. In addition, LTMs help reveal potential mechanisms behind observed space‐time trajectories through linking the webpage‐data derived popularity measure about climate change to a set of socio‐demographic covariates. Our analysis shows that controlling for population density, greater drought exposure, higher percent of people who are 16 years old or above, and higher household income are positively predictive of the trajectory slopes. Higher percentages of Republicans and number of hot days in summer are negatively related to the trajectory slopes. Implications of these results are examined, concluding with consideration of the potential utility of LTMs in space‐time analysis and more generally in GIScience.  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