全文获取类型
收费全文 | 127篇 |
免费 | 8篇 |
专业分类
135篇 |
出版年
2024年 | 1篇 |
2023年 | 2篇 |
2021年 | 1篇 |
2020年 | 1篇 |
2019年 | 5篇 |
2018年 | 5篇 |
2017年 | 10篇 |
2016年 | 9篇 |
2015年 | 7篇 |
2014年 | 6篇 |
2013年 | 15篇 |
2012年 | 4篇 |
2011年 | 5篇 |
2010年 | 6篇 |
2009年 | 2篇 |
2008年 | 6篇 |
2007年 | 2篇 |
2006年 | 4篇 |
2005年 | 5篇 |
2004年 | 2篇 |
2003年 | 5篇 |
2002年 | 3篇 |
2001年 | 3篇 |
2000年 | 3篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1996年 | 3篇 |
1995年 | 1篇 |
1994年 | 4篇 |
1993年 | 1篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1990年 | 3篇 |
1988年 | 4篇 |
1985年 | 1篇 |
排序方式: 共有135条查询结果,搜索用时 0 毫秒
61.
Andreas W. Daum 《Berichte zur Wissenschaftsgeschichte》2010,33(2):214-215
62.
Florian Ströbele Thomas Wenzel Andreas Kronz Ludwig H. Hildebrandt Gregor Markl 《Archaeological and Anthropological Sciences》2010,2(3):191-215
Here, we present detailed electron microprobe analyses and age data of high-medieval lead–silver smelting slags. The mineral
composition data provide a database of all silicate and oxide phases in the slag. Bulk chemistry as well as mineral composition
is used to reconstruct liquidus, solidus, and viscosity of the slag melt. By calculating the mass balance of the smelting
process, a mass ratio of the various compounds used in the smelting process is determined. Through this we were able to discriminate
qualitatively between non-ferrous metal smelting slags and bloomery slags. We also report a new type and process of silver
production in which argentiferous galmei (zinc carbonate) was used as a main silver ore together with galena. The results
indicate a sophisticated high-medieval smelting technology, in which a slag with a low liquidus and a low viscosity was created. 相似文献
63.
This article1 investigates public opinion on New Zealand's foreign policy, drawing on the findings of a comprehensive poll of general public and elite opinion conducted in 2008. It analyses what New Zealanders think about a range of foreign policy issues and whether public opinion matches actual foreign policy. It argues that the majority of the public support the broad parameters of official policy, but that there are significant differences of opinion in some specific areas, particularly trade agreements and defence. These differences correspond in particular to political orientation and age, gender and income level. The article also outlines the key differences between public opinion and the opinion of the positional elite. Overall, it is argued that the New Zealand public does have clear opinions on foreign policy issues and that these are generally consistent. The article proposes more frequent polling and more public debate over foreign policy. 相似文献
64.
65.
66.
Andreas Hess 《Nations & Nationalism》2014,20(1):185-190
67.
68.
69.
70.
Andreas Woyke 《Berichte zur Wissenschaftsgeschichte》2008,31(1):58-67
Reflections about an embedding of nanotechnology in a continuum of the history of science and technology. Nanotechnology is not a completely new technology, we can rather understand it as a continuation and extension of chemical technology. Along this line, it is not only problematic to characterize nanotechnology as a new ‘key technology’ but also the definition of nanotechnology as looking at a particular causality between properties and dimensions of materials seems hardly new. For embedding nanotechnology in such a greater historical context, the development of colloid chemistry at the beginning of the 20th century by Richard Zsigmondy and Wolfgang Ostwald is shown as an important reference point. Modern theories of supramolecular chemistry as those constituted by Jean‐Marie Lehn and others refer to this line of research in colloid chemistry and lead currently to scientific foundations of some nanotechnological fields. The historical embedding of nanotechnology can hence be used as a contribution for a more realistic evaluation of the technological possibilities as well as for a critical estimation of technological visions. 相似文献