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Andreas W. Daum 《Berichte zur Wissenschaftsgeschichte》2010,33(2):214-215
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Niv Horesh John Y. Wong Hongwei Bao Harald Fischer Tiné Jim Masselos Margaret Kartomi 《亚洲研究评论》2010,34(4):513-543
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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
96.
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
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Andreas Hess 《Nations & Nationalism》2014,20(1):185-190
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A group of 400–500 m long, bedding‐parallel calcite veins are exposed in the central La Popa Basin of northeastern Mexico. These veins provide a unique opportunity to determine the kilometer‐scale fluid–rock system associated with bedding‐parallel vein formation, and to test for sampling bias in studies that often use one or two samples to constrain the characteristics of regional‐scale paleohydrogeological systems. We use fluid inclusion microthermometry in conjunction with measurements of δ13C, δ18O, and 87Sr/86Sr ratios to constrain the vein‐forming fluid temperatures, compositions and sources, and compare these values along and between the veins to establish the homogeneity of the vein‐forming fluids and fluid–rock system. The δ13C values of the veins are close to those of the host rock, and average – 3.96‰ (PDB). The δ18O values of the veins are typically 1‰ lower than those of the host rocks, and average – 9.54‰ (PDB). Fluid inclusion homogenization temperatures average 137°C and inclusion salinities are all <6 wt% NaCl equivalent. The 87Sr/86Sr ratios of the veins average 0.70731 and are substantially lower than the values expected for the host rock. Calculated fluid δ18O values range from 4 to 10‰ (SMOW). The isotopic and microthermometric data indicate the veins most likely formed at depths of 3–4 km when meteoric water mixed with upward migrating, warm basinal brines. Vein microstructures and field characteristics indicate they formed from multiple slip events that most likely were associated with transport of individual fluid pulses that migrated along bedding planes. The large‐scale homogeneity of vein geochemistry is remarkable and demonstrates that only one or two samples would be sufficient to accurately characterize the kilometer‐scale paleohydrogeological system for these veins. 相似文献
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The focus of this article is on precompetitive research and development (R&D) cooperation across Europe, as captured by R&D joint ventures funded by the European Commission in the time period 1998–2002, within the Fifth Framework Programme. The cooperations in this program give rise to a bipartite network with 72,745 network edges between 25,839 actors (representing organizations that include firms, universities, research organizations, and public agencies) and 9,490 R&D projects. Participating actors are linked only through joint projects. In this article, we describe a community‐identification problem based on the concept of modularity, use the recently introduced label‐propagation algorithm to identify communities in the network and differentiate the identified communities by developing community‐specific profiles with social network analysis and geographic visualization techniques. We expect the results to enrich our picture of the European Research Area (ERA) by providing new insights into the global and local structures of R&D cooperation across Europe. Este artículo se centra en la cooperación en investigación precompetitiva y desarrollo (I + D) en toda Europa tal y como se manifiesta en iniciativas conjuntas de I + D financiadas por la Comisión Europea durante el periodo 1998–2002, dentro del Quinto Programa Marco (5PM). La cooperación en este programa dio lugar a una red bipartita con 72.745 conexiones entre los 25.839 agentes (representando organizaciones que incluyen empresas, universidades, organizaciones de investigación y organismos públicos), y 9.490 proyectos de I + D. Los agentes participantes están vinculados sólo a través de proyectos conjuntos. En este artículo describimos un problema de identificación comunitaria basado en el concepto de modularidad, usamos el recientemente introducido algoritmo de propagación de etiquetas, Label‐propagation Algorithm (LPA) para identificar las comunidades en la red, y diferenciamos las comunidades identificadas desarrollando perfiles específicos comunitarios mediante el análisis de redes sociales y técnicas de visualización geográfica. Esperamos que los resultados enriquezcan nuestra visión del Espacio Europeo de Investigación (European Research Area, ERA), aportando nuevas perspectivas sobre las estructuras globales y locales de cooperación en I + D en Europa. 本文关注1998–2002年间在第五框架计划(FP5)下由研究与发展联合基金支持的欧盟研发计划中的竞争前欧洲研发合作。该项目合作形成一个在25839个参与者(执行组织,包括企业,大学,研究机构级公共部门)和9490个项目间拥有72745条边的双向网络,参与者仅仅通过合作项目连接。本文描述了基于模块化的社团识别问题。利用最近发展的标签传递算法(LPA)对网络群体进行识别,利用社会网络分析和地理可视化方法构建了群体专属的描述,区分识别出不同研发群体的资料。希望上述结果可以提供欧洲范围内研发合作的全局和局部结构的新视角,从而丰富欧洲研究区(ERA)的图景。 相似文献