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   245篇
  免费   7篇
  2023年   1篇
  2020年   5篇
  2019年   8篇
  2018年   11篇
  2017年   9篇
  2016年   14篇
  2015年   4篇
  2014年   8篇
  2013年   66篇
  2012年   9篇
  2011年   2篇
  2010年   13篇
  2009年   8篇
  2008年   3篇
  2007年   8篇
  2006年   5篇
  2005年   3篇
  2004年   4篇
  2003年   2篇
  2002年   3篇
  2001年   5篇
  2000年   4篇
  1999年   2篇
  1998年   5篇
  1997年   3篇
  1995年   1篇
  1994年   3篇
  1993年   4篇
  1990年   1篇
  1987年   4篇
  1986年   2篇
  1984年   3篇
  1983年   3篇
  1982年   6篇
  1981年   1篇
  1980年   2篇
  1979年   5篇
  1978年   3篇
  1977年   2篇
  1976年   3篇
  1975年   1篇
  1973年   1篇
  1960年   1篇
  1950年   1篇
排序方式: 共有252条查询结果,搜索用时 15 毫秒
21.
Sixty‐four sherds and seven natural clays from prehistoric sites in northwestern Sudan have been submitted to petrological and chemical analysis using XRF spectrometry, EMPA and ICP–MS. According to their texture, the sherds form five different groups. The high contents of P2O5 (more than 0.5 wt%) discerned in 19 samples and the variation of the P2O5 content in two samples of the same vessel can be explained by post‐depositional processes or by the ancient organic contents (e.g., milk) of the vessel. Chemical classification of the pottery bulk suggests that vessels were made locally, as only sherds from the same area show homogeneity of data.  相似文献   
22.
The conduct of American military physicians in prisoner of war (POW) camps has been called into question by the abuse scandals at Abu Ghraib and Guantánamo Bay. This essay explores the experiences of the first U.S. military physicians to confront POW patients in large numbers-events that occurred during the American Civil War. While POWs received sub-standard care in camps north and south, the war also saw the issuance of the first document to outline the rights of POWs. This ambivalence toward the proper care and treatment of the POW is evident in the career of Dr. Eugene Sanger, the first Union surgeon at the prison camp in Elmira, New York. Sanger demonstrated both concern about the sanitary condition of the camp and pride in the deaths of POWs as furthering the overall war aims. His cruelty attracted some censure, but Sanger never faced disciplinary action. He was honorably discharged and went on to become the Surgeon General of his home state. This article places his actions at Elmira in the context of medical ethics, Army orders, and Northern opinion in 1864, and it will argue that the lack of Federal response to Eugene Sanger's poor record while serving at the prison set a precedent for inferior medical care of POWs by American military physicians.  相似文献   
23.
24.
There is a substantial political-science literature that discusses the notion of consensual norms in the US Supreme Court. Most of this literature assumes that consensual norms exist, rather than proving their existence. Caldeira and Zorn ( American Journal of Political Science 42: 874-902, 1998) use the method of cointegration developed in econometric time-series analysis to prove the existence of a single consensual norm in the US Supreme Court. This study applies cointegration analysis to historical time-series data on dissenting and single judgments to examine whether there is a single consensual norm in the High Court of Australia. The study finds that a single consensual norm does not underlie decision making in the High Court. This result is explained on the basis that the institutions underpinning decision making and the approach to decision making are different between the Australian High Court and the US Supreme Court.  相似文献   
25.
26.
27.
This paper presents a review and synthesis of archaeological surveys in western Syria and southern Turkey, alongside finds from recent excavations at Tell Qarqur, Syria, revealing regional patterns of late Roman settlement and land use in the lower Orontes River Valley. Survey data show that the late Roman period witnessed a peak in settlement density, with the extension of occupation into previously unoccupied areas and widespread agricultural intensification. Excavations of a typical lowland site at Tell Qarqur reveal an opulent building complex, possibly a church, with a columned hall, elaborate mosaic floor and frescoed interior. Analysis explores the process of agricultural intensification during the late Roman period, the relationship between lowland settlements and the better‐known Dead Cities of the limestone massif to the east, and the ultimate abandonment of the settlement system following the seventh century AD.  相似文献   
28.
Early medieval attitudes to dreams and visions have been seen either as negative, products of an ostensibly repressive theological tradition, or positive, as suggested by the apparent ease with which many narratives treat these phenomena. This article explores the relationship of early medieval views on dreams to those of the church Fathers and suggests that views on the value and handling of dreams vary in accordance with the probable audiences and aims of our sources. Instead of uniform views either repressive or permissive, we see a variety of attitudes and techniques, aiming to satisfy both practical needs and theological concerns.  相似文献   
29.
Urban Growth in the 1990s: Is City Living Back?   总被引:3,自引:0,他引:3  
The 1990s were an unusually good decade for the largest American cities and, in particular, for the cities of the Midwest. However, fundamentally urban growth in the 1990s looked extremely similar to urban growth during prior post–war decades. The growth of cities was determined by three main trends: (1) cities with strong human capital bases grew faster than cities without skills, (2) people moved to warmer, drier places, and (3) cities built around the automobile replaced cities that rely on public transportation. Although the negative impact of population density diminished slightly in the 1990s, there is no real evidence for a return to large, dense cities.  相似文献   
30.
Scientists from the National Institute of Standards and Technology (NIST) worked in a collaborative partnership with archaeologists from the National Park Service's (NPS) Submerged Resources Center (SRC) to develop a finite element model (FEM) of the battleship USS Arizona. An FEM is a computer-based engineering model that calculates theoretical stresses, propagation of force, and shape changes to a structure under loads using thousands or even millions of individual elements whose individual responses are well understood. NIST researchers created an FEM of an 80 ft. (25 m) midships section of the Arizona site to analyze archaeological site formation processes on the sunken battleship, in particular to determine the current condition of the wreck and predict its future strength and structural integrity as it continues to corrode. The NIST's FEM study is one aspect of a larger project under the direction of the NPS, the USS Arizona Preservation Project, whose goal is to determine the nature and rate of corrosion affecting USS Arizona, and to model its long-term structural deterioration. The FEM incorporates findings from other key components of the USS Arizona Preservation Project, such as steel hull corrosion rates, structural surveys of the vessel, sediment compaction studies, and analysis of the concretion that covers the ship's hull, into a single tool that is being used to predict how the wreck will degrade in the future.  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