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   617篇
  免费   23篇
  2024年   2篇
  2023年   5篇
  2022年   11篇
  2021年   8篇
  2020年   16篇
  2019年   18篇
  2018年   22篇
  2017年   18篇
  2016年   22篇
  2015年   15篇
  2014年   13篇
  2013年   45篇
  2012年   30篇
  2011年   59篇
  2010年   31篇
  2009年   46篇
  2008年   47篇
  2007年   65篇
  2006年   56篇
  2005年   39篇
  2004年   10篇
  2003年   15篇
  2002年   17篇
  2001年   11篇
  2000年   7篇
  1999年   6篇
  1998年   1篇
  1997年   2篇
  1994年   1篇
  1993年   1篇
  1979年   1篇
排序方式: 共有640条查询结果,搜索用时 15 毫秒
1.
The original fineness of coins is very important information that can help us to understand the commercial situation in a wide historical context. This paper deals with a comparison of analytical methods suitable for the evaluation of the actual and original fineness of coins based on a detailed case study of a medieval coin sample. Both non‐destructive (i.e., scanning electron microscopy/energy‐dispersive X‐ray spectroscopy, X‐ray fluorescence, atomic force microscopy and hydrostatic weighing) and destructive (i.e., inductively coupled plasma – mass spectrometry and the Volhard titration method) techniques were used. The original fineness can be also deduced from knowledge of the internal structure of the coin (limited miscibility of copper and silver). A new analytical method based on a combination of a micrograph of the metallographic cross‐section with consequent image analysis was developed for determination of the original fineness. The proposed approach is relatively simple and provides reliable values. Sample heterogeneity and its impact on the determination of fineness are also discussed.  相似文献   
2.
As social and cultural contexts change and globalization spreads, the number of transnational-marriage migrants mainly from Southeast Asia has increased in Taiwan. Using institutional ethnography, this article investigates the roles of local non-governmental organizations (NGOs) and projects aimed at helping foreign spouses to adapt to their new life. I mainly elaborate that NGOs emerge as important actors in assisting and empowering transnational spouses to ‘become locals’. In empowerment projects, foreign spouses are given a voice to elaborate themselves. However, this article elaborates that these projects are a scheme of education to shape each such migrant into a proper ‘Taiwanese wife/mother/daughter-in-law’. Also, these projects particularly promote ‘exoticism’ of migrants and become key sources of how local people understand the images of ‘foreign spouses’. As a result, though NGOs play positive roles in empowering foreign spouses, we need to be aware that NGOs’ efforts may ironically become a mechanism to strengthen transnational spouses’ gender roles and cultural stereotypes.  相似文献   
3.
4.
明代中后期,闵行镇凭借其便利的交通条件与繁荣的棉花种植业,成为上海县重要的商业市镇。近代以来,随着上海城市的发展,闵行镇与上海城区间经济联系不断密切,政治地位也日趋重要。新中国成立初期,优先发展重工业的国家政策与华东沿海地区的战略地位,使得民国时期奠定重工业基础的闵行镇备受各方重视。在国家政策、经济体制、地方利益等因素的综合作用下,闵行镇最终由江苏省上海县划归上海市。  相似文献   
5.
苏小东 《安徽史学》2007,(1):99-105
刘铭传以武将而跻身于封疆大吏之列,其一生之建树重在“事功”而非“理论”。正因为如此,他虽然也曾就海防及其相关问题有过全面系统的论说,但其认识水平显然不及同时代之佼佼者。关于台湾在中国海防中的战略地位,他也是在领导抗法保台、建台的过程中逐步加深认识的,并以首任台湾巡抚之地位不遗余力地将其思想主张付诸实践,开创了包括海防在内的台湾近代化新局面。刘铭传加速台湾建设、加强台湾海防的初衷是为了抵御日本的侵略,不料数年之后,台湾竞因北洋海防的崩溃而落入日本之手。这绝不是刘铭传个人的悲哀,实乃国家民族之大悲剧。  相似文献   
6.
In 2000, a well‐preserved, c.21 m‐long shipwreck, Doel 1, was found upside‐down in a silted‐up creek near the river Scheldt (Belgium). An interdisciplinary research project was initiated, including 3D registration of all timbers, wood species identification, dendrochronology and archaeobotanical analysis of the caulking material. Doel 1, of which 70% is preserved, displays the construction features of a cog. Unseasoned wood was used and dated by dendrochronology to AD 1325/26. Remarkable features include the symmetrical layout of the bottom planks, the atypical arrangement of the frames to the fore, and evidence of partial dissassembly of the ship after intensive use.  相似文献   
7.
This paper investigates the context of student learning in study abroad programs, drawing on ethnographic research on a semester long study abroad program in South India. We show how students use multiple constructions of time and space as a framework for understanding cultural differences and for understanding what it means for them to “experience” India. We argue that students' conceptualization of space and time in the study abroad location also impacts what kinds of activities they consider to count as valuable forms of learning. Students' ideas about India shape their expectations of what the pace, workload, and activities of the study abroad program in India should entail. Their concepts of Indian time and space lead them to privilege “experience”-based learning over classroom-based or scholarship-based learning. In conclusion, we show how these insights have implications for study abroad pedagogy. Here, we suggest that student learning that is entirely based on “experience” outside the classroom is inherently limited and that students need to contextualize their field-based learning experiences with insights from critical, historical and social science research.  相似文献   
8.
The quick and accurate identification of post-earthquake rescue objects can minimize the casualties and property loss caused by earthquakes. With the rapid development of remote sensing technology, rescue objects can be identified through high-resolution remote sensing images. There are two main categories of approaches to identify rescue object through high-resolution images: automatic extraction by a computer and visual judgment by professionals. Although results can be obtained quickly by using automatic extraction, the accuracy of the results is unacceptably low. For visual judgment, the large demands for time and professionals restrict its wide practical application. In this study, we introduce crowdsourcing into the identification of post-earthquake rescue objects. First, we integrate the advantages of the computer and crowdsourcing, which means that the computer takes advantage of the speed of information processing, while crowdsourcing makes full use of human recognition capabilities. Second, we take visual judgment tasks out of the hands of professionals and entrust the tasks to workers in a crowdsourcing platform. Not only are the human resources infinite, but we can also improve the efficiency of identifying rescue objects. Third, we propose a crowdsourcing model that improves the quality of the results and saves human resources. Finally, experimental results demonstrate that our solution is feasible.  相似文献   
9.
The Ma?agan Mikhael B shipwreck was found in 1.5m of water, beneath 1.5m of sand, 70m off the Mediterranean coast of Israel. The hull remains are in a good state of preservation, comprising the endposts, aprons, framing timbers, hull planks, stringers, and bulkheads. The finds comprise rigging elements, wooden artefacts, organic finds, animal bones, glassware, coins, bricks, stones, ceramic sherds, and complete amphoras. The shipwreck was dated to the 7th–8th centuries AD; which makes it an exceptional source of information regarding various aspects of ship construction, seamanship, and seafaring in the area in Late Antiquity.  相似文献   
10.
扎什琍玛佛像因特征明确、像式丰富、工艺精细,在故宫珍藏的佛教造像中独树一帜。清宫的扎什琍玛像多附有皇家特有的黄条题记。本文从这些黄条所记内容入手,结合档案资料,对此类造像进行来源、类型及题材风格的细化探究,并进一步说明扎什琍玛对清宫佛教造像风格的深刻影响及其在促进西藏与内地政治、经济、文化联系方面曾经发挥的历史作用。  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