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   2521篇
  免费   428篇
  2024年   1篇
  2023年   13篇
  2022年   18篇
  2021年   60篇
  2020年   89篇
  2019年   185篇
  2018年   161篇
  2017年   162篇
  2016年   177篇
  2015年   148篇
  2014年   144篇
  2013年   431篇
  2012年   234篇
  2011年   162篇
  2010年   119篇
  2009年   94篇
  2008年   125篇
  2007年   109篇
  2006年   84篇
  2005年   63篇
  2004年   67篇
  2003年   66篇
  2002年   41篇
  2001年   55篇
  2000年   36篇
  1999年   13篇
  1997年   6篇
  1996年   5篇
  1995年   9篇
  1994年   8篇
  1993年   2篇
  1992年   13篇
  1991年   8篇
  1990年   1篇
  1989年   5篇
  1988年   5篇
  1987年   7篇
  1986年   5篇
  1985年   5篇
  1984年   10篇
  1982年   1篇
  1981年   1篇
  1980年   1篇
排序方式: 共有2949条查询结果,搜索用时 15 毫秒
101.
Because it associates animals with one of the most vital topics in human history, the historiography of the cross‐connections between race and animal‐breeding is at once controversial and inspiring. This article wishes to position this historiography in a more systematic framework than has been done thus far by examining both its merits and failings along with the more and less appropriate ways to write on the subject. The article identifies two main narratives in race–animal‐breeding historiography: the influence narrative and the projection narrative. The first reveals how perceptions of animal breeds and livestock‐breeding practices influenced the rise of racialist and eugenic worldviews. By contrast, the second shows how conceptualizations of human racial segregation contributed to the construction of ideas about the subdivision of domestic animal species into different breeds. The article argues that despite the projection narrative's inherent anthropomorphism, this perspective renders it possible to draft a nonanthropocentric history of the cross‐connections between race and animal‐breeding with a focus on human–animal relations rather than on human society.  相似文献   
102.
The Ford Nuclear Reactor operated from 1957 to 2003 on the University of Michigan's North Campus in Ann Arbor, Michigan. Over its 45‐year lifespan, the facility played a key role in archaeometric research, fostering early methodological studies using INAA and supporting archaeological materials science investigations of lithics, ceramics, metals and bone. One small part of the FNR's abundant legacy was the initiation of trace‐element studies of Oaxacan ceramics, which are now beginning to shed light on early exchange interactions and the origin of the Monte Albán state in the Valley of Oaxaca, Mexico, between 500 bce and 200 ce .  相似文献   
103.
This paper describes the archaeometric research conducted at the SLOWPOKE Reactor Facility of the University of Toronto (SLOWPOKE‐Toronto) during its existence from 1971 to 1998. The contributions to student teaching and research are described, and the total contribution of the facility to studies of an eclectic assortment of ancient and historic materials is addressed.  相似文献   
104.
Archaeological bones, found close to Mexico City (Tlatelcomila), with alterations due to probable thermal exposure attributed to a possible case of cannibalism, have been characterized by XRD, SAXS and SEM. It is shown how these non‐destructive techniques, which are not conventionally used in archaeological research, may provide useful information. The deterioration degree of the bone structure is quantified through parameters such as gyration radius or fractal dimension. As some of the reported modifications could be attributed to diagenesis, a discussion is presented in terms of bone crystallinity and ionic exchange. Furthermore, the hydroxyapatite crystallite size increased depending on colour: this feature is not explained by diagenesis—it can only be attributed to temperature. We conclude that the samples were thermally treated. Indeed, thermal treatment alters the structure and morphology of bone at a very fine level (microscopic and nanometric), while morphology follows the structural modifications. It is determined that the studied human bones were treated at three different temperatures close to 100, 250 and 600°C. Therefore, they were either boiled (barbacoa) or grilled.  相似文献   
105.
The calcareous skeletal remains of various microscopic organisms such as foraminifera and ostracods are a striking feature of thin sections of many archaeological ceramics from the Aegean Bronze Age. While the presence of these calcareous microfossils in pottery has been noted for some time, attempts to utilize them to further the aims of ceramic compositional analysis have been few in number. In the following paper, we take a first detailed look at the occurrence and utility of calcareous microfossils in archaeological ceramics. By presenting selected case studies from the Bronze Age of Crete, we demonstrate the potential of calcareous microfossils, especially the extremely small ‘nannofossils’ and the highly contextual geological information that they contain, in terms of the characterization and grouping of ceramics, the determination of their provenance and the reconstruction of ancient technology.  相似文献   
106.
I. K. BAILIFF 《Archaeometry》2007,49(4):827-851
Fired clay brick samples, obtained from a group of seven high‐status late‐medieval and post‐medieval buildings in England ranging in age from c. ad 1390 to 1740, were dated by the luminescence method using an optically stimulated luminescence (OSL) technique. The results obtained indicate that, when applied to quartz extracted from brick, the technique is capable of producing dates that are in consistently good agreement with independent dating evidence for the buildings. For six samples taken from a group of four dating ‘control’ buildings the mean difference between the central values of luminescence and assigned ages was 5 ± 10 years (SD, n = 6). The methodology used is appropriate for application to other standing buildings in other temporal and geographic regions, and may be used with confidence where conventional dating methods are less certain. The study also examines the luminescence characteristics of quartz and the characteristics of the lithogenic radionuclides in brick samples and identifies various aspects related to the assessment of experimental uncertainty in testing the reliability of the method.  相似文献   
107.
Voluntary environmental programs (VEPs) have been used as a policy tool in the United States since the early 1990s and come in many forms. Early assessments of VEPs targeting changes in production processes showed that industrial participants improved their environmental performance and VEPs were celebrated as a viable alternative to more traditional regulation. Recent analyses using more sophisticated techniques, however, paint a less favorable picture. On the one hand, firms appear willing to sign up to VEPs, and in some cases, participants may be able to create a shield against future losses in shareholder value. On the other hand, these VEPs targeting production processes appear not to generate significant pollution abatement. The latter finding is particularly disturbing and this article discusses various explanations, including institutional failure and participant motivations. Future research needs to focus on understanding the firm motivation to invest in production‐related pollution abatement under a VEP. For policymakers, the research offers a warning on the limited impact to date of VEPs targeting production processes. However, the multitude of other VEPs, such as those which target new product development and changing market demands, merit a closer look to determine the overall potential of VEPs to engender positive environmental change.  相似文献   
108.
Science Cities: What the Concept of the Creative City Means for Knowledge Production. – The article aims to show that the relationship of science and the city has changed since the 1970s in the context of the knowledgeable society. While cities have principally been regarded as the typical space of science, of new ideas and innovation for centuries, since the 1960s and 1970s universities, research institutes as well as industrial research institutes have relocated to the periphery of cities. There, however, these sites of knowledge have been organized in an ‘urban mode’. That means that the concept of the city as a place of science and innovation has determined the architectural, spatial, and social organization of these sites on the periphery of cities. Certain features of the city have been copied, such as social infrastructures, places of communication, restaurants, cafes etc., while others have been left out – housing, cinema, theatre etc. An ‘urban mode of knowledge production’ in the sense of a very stylized model of the city has become a tool to enhance the production of scientific and technological knowledge. – The article exemplifies this by focusing on a case study, namely of the so‐called ‘Science City’ of the Siemens Company in Munich‐Neuperlach.  相似文献   
109.
肯尼迪在美国面临巨额国际收支逆差的背景下入主白宫。严重的逆差导致美国的黄金大量外流,引起西方世界对美元信用的置疑。因此,调节逆差成为肯尼迪政府的重要使命。肯尼迪政府调节逆差的政策主要体现在肯尼迪提交给国会的两份特别咨文中,即1961年2月6日的“黄金和国际收支逆差特别咨文”和1963年7月18日的“国际收支特别咨文”。以两份咨文为蓝本,有关部门展开了系列的开源节流行动。美国的逆差调节行动使美国政府内部和北约盟国间的斗争起伏跌宕,充分暴露出权力政治的实质。  相似文献   
110.
"承负说"与两汉灾异论   总被引:2,自引:0,他引:2  
韩吉绍 《史学月刊》2007,1(12):29-36
作为《太平经》基础理论的"承负"说主要有两层含义:一是善恶报应,继承汉代之前中国本土的善恶报应思想;二是对汉代社会危机提出的一套解释系统,此与灾异论的盛行具有重要关联。前者为《太平经》对下层民众进行宗教教化准备了前提,后者为其政治改良方案的提出铺平了道路。尤其后者,对两汉之际不同派别的道教运动产生了革命性的影响,进而深刻影响了后汉之政治变迁。  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