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   1297篇
  免费   49篇
  1346篇
  2023年   14篇
  2020年   39篇
  2019年   36篇
  2018年   50篇
  2017年   61篇
  2016年   67篇
  2015年   39篇
  2014年   45篇
  2013年   333篇
  2012年   41篇
  2011年   35篇
  2010年   41篇
  2009年   40篇
  2008年   38篇
  2007年   49篇
  2006年   30篇
  2005年   34篇
  2004年   28篇
  2003年   21篇
  2002年   17篇
  2001年   20篇
  2000年   10篇
  1999年   18篇
  1998年   6篇
  1997年   7篇
  1996年   11篇
  1995年   7篇
  1994年   9篇
  1993年   6篇
  1992年   6篇
  1990年   8篇
  1989年   7篇
  1988年   5篇
  1987年   8篇
  1986年   10篇
  1985年   11篇
  1984年   7篇
  1983年   5篇
  1982年   6篇
  1981年   7篇
  1980年   6篇
  1979年   11篇
  1978年   11篇
  1977年   6篇
  1976年   6篇
  1975年   8篇
  1973年   6篇
  1972年   9篇
  1970年   5篇
  1969年   5篇
排序方式: 共有1346条查询结果,搜索用时 0 毫秒
81.
82.
Investment is an important decision for economic development, balanced growth and public welfare. There are many factors influencing investment. Thus, investment must be evaluated with multidimensional methods. Using taxonomy and principal component analysis this study attempts to determine appropriate investment areas in planned provinces in the Black Sea Region. Analyses were based on a number of demographic, economic, health, education, employment and cultural indicators. Results indicated that provinces were grouped into four clusters. Gümü?hane and Bayburt were determined to have the highest priority for investment in the manufacturing industry.  相似文献   
83.
Verglichen mit vielen anderen, auch europ?ischen L?ndern, existiert in der Bundesrepublik Deutschland seit vielen Jahren ein ausgeklügeltes und komplexes System der Raumordung. Seit den ersten Anf?ngen hat sich viel ver?ndert. DIPL.-GEOGR. UTE C. BAUER sprach mit PROF. DR. DIETRICH FüRST, früher Professor für Landesplanung und Regionalforschung an der Universit?t Hannover, über den Wandel, den die Raumordnung in den letzten Jahrzehnten durchgemacht hat. Als Experte für Regionalentwicklung und -?konomie erl?utert er die wichtigsten Tendenzen und Aufgaben, denen sich die Disziplin heute stellen mu?.  相似文献   
84.
Uganda faces continual challenges as a low‐income nation reliant on international donors and non‐state actors. It was also one of the first countries to face a population‐wide HIV epidemic, a disease that can strain state capacity to its limits. One would expect that such a combination would weaken the governance structures in a developing country; yet, if anything, the Ugandan state has emerged from its HIV crisis with its legitimacy bolstered. This article reviews the Ugandan response to HIV/AIDS, analysing the ways in which the epidemic has provided a new arena for the Ugandan state to engage with international actors.  相似文献   
85.
86.
G. HADAS  I. SEGAL  O. YOFFE  M. STEIN 《Archaeometry》2009,51(6):1008-1014
A wooden Roman anchor was discovered at the retreating shore of the Dead Sea, north of Ein Gedi. The anchor's wood material was coated by a thick veneer of aragonite and gypsum crusts. The wood was dated by radiocarbon to the early Roman time in the Levant. Lead isotope analyses carried out on the Pb–Fe–Cu anchor material (remains of the anchor's metal parts) yielded ratios that indicate origin of the metal in Italian ores (maybe Tuscan). For the wooden part of the anchor a local tree was used.  相似文献   
87.
88.
Michael Schiffer’s theoretical and methodological contributions to archaeology are substantial. For the last two decades, Schiffer has become increasingly interested in the history of electrical technology, including portable radios, electric automobiles, eighteenth-century electrostatic technology, and, most recently, nineteenth-century electric light and power systems. Schiffer has long held a behavioral view, which focuses analytical attention on interactions between humans and material things, including complex technological systems (CTSs). For Schiffer, two key aspects of the evolution of CTSs are stimulated variation, defined as an increase in invention resulting from changing selective conditions, and cascading, defined as sequential spurts of invention that occur through the recognition of emergent performance problems in a CTS. To attain maximum usefulness, these concepts should be placed in a modern evolutionary framework that correctly identifies, and does not oversell, the role played by cultural selection. Research on individual and social learning provides the critical link between Schiffer’s stimulated variation and cascade models and the diffusion of CTSs.  相似文献   
89.
90.
This article analyzes the role that commercial interests played in Swiss perceptions of informal imperialism in China during the 1920s. Commercial interests were the driving force behind the establishment of Swiss relations with China in 1918 and Swiss rejections of Chinese demands to abolish extraterritoriality in the 1920s. Swiss commercial relations with China were deeply rooted in the social, economic, and political institutions and processes developed by informal imperialism in China. During the Chinese antiforeign agitation in the 1920s, the Swiss press criticized the unequal treaties as an example of imperialism in China but ignored Switzerland’s participation in it. This discrepancy between the official and media perceptions of Swiss commercial interests in China was caused by the fact that Switzerland’s dependence on privileges connected to the unequal treaties clashed with Swiss national mythology, which was based on neutrality and anti-imperial narratives. Moreover, the negligible importance attributed to Swiss trade with China and the increasing focus on the nationality of foreign companies in China allowed the Swiss media to ignore Swiss commercial interests in China. As a result, Swiss complicity in informal imperialism was downplayed by the Swiss press, which ignored the importance of Swiss commerce to Sino–Swiss relations.  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