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   959篇
  免费   23篇
  2024年   1篇
  2023年   2篇
  2022年   9篇
  2021年   23篇
  2020年   21篇
  2019年   10篇
  2018年   17篇
  2017年   15篇
  2016年   16篇
  2015年   21篇
  2014年   11篇
  2013年   41篇
  2012年   48篇
  2011年   87篇
  2010年   76篇
  2009年   107篇
  2008年   81篇
  2007年   75篇
  2006年   90篇
  2005年   60篇
  2004年   33篇
  2003年   23篇
  2002年   25篇
  2001年   15篇
  2000年   29篇
  1999年   12篇
  1998年   4篇
  1997年   9篇
  1996年   3篇
  1995年   3篇
  1994年   5篇
  1993年   4篇
  1992年   3篇
  1991年   2篇
  1990年   1篇
排序方式: 共有982条查询结果,搜索用时 31 毫秒
1.
水资源短缺一直制约着京津唐地区经济和社会的发展。20世纪70年代,因缺水引发的经济、社会问题逐渐凸显,促使中央和地方政府开始考虑实施跨流域调水工程。引滦工程作为北方最大的跨流域调水工程,其决策经历了曲折的过程。1958年,北京和唐山曾分别提出引滦河水的设想,唐山还实施了引滦入还和引还入陡工程。1972年,海河流域大旱促使中央做出加快实施引滦工程的决定,但由于地质情况复杂等原因,引滦工程设计方案被反复修改。1981年,天津提出了单独引滦济津路线并得到了中央的支持。引滦工程对缓解京津唐用水紧张发挥了重要作用,天津是引滦工程受益最大的地区。  相似文献   
2.
兵团文化研究综述   总被引:1,自引:0,他引:1  
郭换平 《丝绸之路》2010,(10):34-37
兵团文化是兵团人在屯垦戍边的过程中所创造的独具特色的文化,具有巨大的感召力和凝聚力,对于传播中华文化、吸收各民族的优秀文化、维稳固边、促进兵团和谐社会的构建都发挥了重大的作用。目前,学术界对于兵团文化研究的成果颇丰,本文从兵团文化的内涵、内容、特征、作用以及如何发展兵团文化着手,对以往的研究成果进行梳理。  相似文献   
3.
吴密 《文献》2021,(2):167-176,F0002
《河南卢氏曹先生教泽碑文》是鲁迅为曹靖华之父曹植甫撰写的一篇碑文,碑文原稿连同附带的一封书信一直没有被外界发现和披露。近日碑文和书信手稿首度现身公众视野,从其内容、特征和相关记载分析,可以确定为鲁迅手书原稿无疑。这两件手稿的发现,为我们对比研究《教泽碑文》的原稿、清稿、初刊本、文集本、全集本等诸多版本提供了重要依据,解决了1986年所立碑文石刻文字的底本问题,同时也廓清了包括曹靖华本人在内对这篇碑文手稿回忆的不准确之处。  相似文献   
4.
5.
汉代漆器的剖析   总被引:2,自引:2,他引:0  
通过制备并分析一系列模拟漆膜样品。建立了有助于鉴定汉代漆器成分的剖析方法。经裂解气相色谱、差热分析、色谱一红外联用等现代分析技术对出土的汉代漆器残片样品的综合分析,证实在西汉漆器制造中已使用桐油或其它的添加剂,并依据剖析的结果,对某些汉代漆器的原材料差异作了初步探讨。  相似文献   
6.
7.
本文论述了图们江地区国际性城市体系建设的必要性,提出了城市体系等级结构、职能结构和空间结构的构建设想及管理原则,并初步估算了城市体系发展各项基础设施建设及投资规模。  相似文献   
8.
The bodies and glazes of 27 early Western Zhou proto‐porcelain samples from Yejiashan cemetery, Hubei Province, were analysed using LA‐ICP–AES, SEM, XRD, a thermal expansion instrument and other analytical methods. The results indicated that the bodies of all samples were characterized by high silicon and low aluminium, and were made with porcelain stone raw materials found in the south of China. The glazes are typical of high‐temperature calcium glazes of the CaO (MgO) – K2O (Na2O) – Al2O3 – SiO2 series, with relatively high Mn and P content, which was probably caused by the addition of plant ashes. The physical properties and phase compositions of Yejiashan proto‐porcelain show that firing processes were still in the early stages of development in ancient China. Multivariate statistical analyses indicated that Yejiashan proto‐porcelain might have come from the Deqing area, in Zhejiang Province. These results provide new archaeological evidence for research on issues related to material flow in the Western Zhou dynasty.  相似文献   
9.
Yelang (夜郎), a mysterious state located in the south‐western area of early China and dating from the Bronze Age to the Early Iron Age (1300 bc – ad 25), is a cultural interactive junction between the Yunnan–Guizhou Plateau and the Yangtze River Basin. The Zhongshui Basin in Weining County, Guizhou Province, was one of the important distribution areas of the Yelang civilization. This area, which includes sites at Jigongshan (鸡公山; 1300 – 800 bc ), Hongyingpan (红营盘; 700 – 400 bc ) and Yinzitan (银子坛; 400 bc – ad 25), has provided a very integrated chronology, spanning from the Bronze Age to the Early Iron Age in the eastern Yunnan – western Guizhou area. To investigate human migration and horse‐trading at these Yelang sites, we conducted a strontium isotopic analysis on the teeth enamel of humans and horses unearthed from these three sites. The results indicated the following: (1) people at the earlier sites (Jigongshan and Hongyingpan) were all indigenous, whereas in the Yinzitan cemetery, there was a more immigrant population, and all the people who were buried in an upper limb flexed supine position were non‐local; and (2) most of the horses found at the Jigongshan and Yinzitan sites show different provenances, probably related to the famous Dian (滇) and Zuo (筰) horses recorded in historical documents, providing more clues for further study on horse‐trading in South‐West China during the Bronze Age and the Early Iron Age.  相似文献   
10.
A human skull, buried about 2500 years ago in a Bronze Age cemetery at Jinggouzi, a site of an important ethnic group in ancient China, appeared to have characteristics of fibrous dysplasia. The CT images indicated a reduction in bone density and relatively homogeneous lesions. More features were revealed using CT reconstruction techniques. Lesions seen in low‐magnification images using a 3D deep‐field microscope had an irregular honeycomb‐like structure. At higher magnification, the trabeculae morphology and the gaps between the trabeculae were irregular and varied in size and shape. Paraffin‐embedded specimens stained with HE showed trabeculae with tortuous irregular arrangements varying in shape and width. The irregular trabeculae of woven bone has been described as having fibrous dysplasia. Molecular analysis of the GNAS gene indicated no mutation. This provides a non‐invasive approach for us to make more comprehensive diagnoses and to assist research into ancient human diseases.  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