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排序方式: 共有288条查询结果,搜索用时 15 毫秒
191.
CARLOS GUTIERREZ BLANCO M. DOLORES GONZÁLEZ AZPÍROZ ADOLFO FERNÁNDEZ VALDÉS 《Archaeometry》2008,50(5):877-886
A collection of seven representative jets from Asturias (Spain) was studied. Some artisans of the Asturian jet industry established the quality criteria of the jet based on the user‐friendly properties of this material. In this work, we study the relationship between the working quality of asturian jets and their structure using parameters defined by liquid 1H‐NMR. With this aim, certain parameters calculated from the NMR results were used to provide information about the structure of compounds extracted from jets. 相似文献
192.
LAURE DUSSUBIEUX AURELIE DERAISME GÉRARD FROT CHRISTOPHER STEVENSON AMY CREECH YVES BIENVENU 《Archaeometry》2008,50(4):643-657
This study discusses the relevance of compositions obtained using laser ablation – inductively coupled plasma – mass spectrometry (LA–ICP–MS) for the purpose of identifying the provenance of copper‐based artefacts found in Virginia at Native American sites dated from the 16th to the 18th centuries. Ten artefacts were investigated by scanning electron microscopy – energy dispersive spectrometry (SEM–EDS) to visualize the corrosion and characterize the heterogeneities in the metal and electron probe micro‐analysis (EPMA) to determine separately the compositions of the intact metal and of the corrosion product. It is shown that the corroded surfaces are highly depleted in zinc but that representative concentrations can be determined by sampling the deeper, uncorroded metal. In contrast, lead values are highly variable because of the heterogeneous distribution of this metal within the bulk copper. Despite these problems, brass is easily identifiable and American native copper and European smelted copper can be unambiguously distinguished with LA–ICP–MS on unprepared artefacts using As, Ag, Ni and Sb trace elements. 相似文献
193.
194.
DAVID MARTIN JONES 《International affairs》2008,84(4):735-756
In November 2007, the heads of the ten member governments of the Association of South‐East Asian Nations (ASEAN) signed a charter that will, once ratified, give the association a legal personality. The charter, significantly, requires more of its members than a reassertion of the traditional ASEAN norm of non‐interference and the practice of consensus. The charter lists a number of novel goals among the organization's purposes: ‘to strengthen democracy, enhance good governance and the rule of law, and to promote and protect human rights and fundamental freedoms.’ In view of the wide economic and political disparities between the member states of ASEAN, this article examines whether strengthening democracy would in fact facilitate ASEAN's goal of becoming an integrated political, economic and security community. Rather than enhancing an integrated community, democratization would arguably create a faultline between the more politically mature and economically developed states and a northern tier of less developed, authoritarian single‐party dominant regimes in South‐East Asia. Moreover, given China's emerging political and economic importance to the region, such a strategy would, as if by an invisible hand, draw the more authoritarian ASEAN states into China's less than democratic embrace. This article concludes that rather than strengthening democracy, ASEAN's charter needs urgently to reinforce practices of rule governance and mechanisms of market integration to enhance both ASEAN's economic profile as well as the region's autonomy. 相似文献
195.
The year of the insurgents: the 2008 US presidential campaign 总被引:1,自引:0,他引:1
MARTIN WALKER 《International affairs》2008,84(6):1095-1107
The wars in Iraq and Afghanistan, Bush's unpopularity at home and abroad and the looming threat of recession would have made a gripping drama of the 2008 presidential election campaign even without the ground‐breaking emergence of the first credible black and female candidates for the White House. But the defeat of the Democratic establishment's front‐runner, Hillary Clinton, by a little‐known freshman Senator of mixed ancestry suggested that this was to be the year of the insurgent, just as the Republicans rallied to the least loyal and most contentious of their candidates, the maverick Senator John McCain. The extraordinarily attractive and articulate Senator Barack Obama re‐wrote the rule book on winning primaries and caucuses with the help of Silicon Valley and an unprecedented turnout among black and young voters, before veering sharply to the centre once the nomination was secured. Orthodoxy returned at the conventions, with Obama picking a safe centrist as running mate and McCain choosing a Christian conservative, although generating great excitement by nominating a woman and undermining the usual democrat advantage among female voters. And for all the talk of a ‘new politics’, the year of the insurgents came down at the end, as US elections usually do, to a handful of swing states and the money and organization to win them. 相似文献
196.
This article provides a synthetic account of the historical development of London's water supply system within its wider national context, and addresses the current organizational setting of the water sector. Particular attention is paid to the post-Second World War period, which marked a transition towards integrated water management in England and Wales, a trend that has been consolidated since the 1970s. The article emphasizes the continuities and contradictions arising from the different combinations of public and private management strategies characterizing the UK water sector, and their implications for the sustainable management of water resources. It argues that there exists an in-built contradiction in the current institutional framework between the profit-oriented rationale of the private operators and the goals of efficiency, equity, and environmental sustainability pursued by the water regulators. Within this framework, it highlights the key policy issues facing the metropolitan water systems, and suggests what their most likely trajectories might be in the foreseeable future. 相似文献
197.
Michel Rochefort Thi-Thanh-Hiên Pham Paul-Émile Tchinda Logan Penvern 《The Canadian geographer》2024,68(1):101-114
When it comes to making planning and development decisions, the concepts of small, medium-sized, or large cities are sometimes used to adapt public policies and instruments, or even to highlight challenges that are specific to certain categories of city. In this article, we take a look at the various dimensions that can be used to characterize cities, so as to empirically test a multi-criteria approach and build a typology of Quebec cities. Using an ascending hierarchical classification, we derive 11 classes of cities, whose conceptualization and graphic representation enable us to highlight their role and, in part, to localize their polarized area. This article complements and adds to works undertaken by other researchers over the last 20 years. Although it does not aim to propose specific changes to public policies and instruments, this article may serve to inform public decision makers in the development of such policies and instruments, and to enrich academic debates on the nature of small and medium-sized towns in particular. 相似文献
198.
199.
VAHÉ TACHJIAN 《Nations & Nationalism》2009,15(1):60-80
ABSTRACT. This essay focuses on the process of ‘rebuilding’ the Armenian nation in the newly constituted states of the Middle East (Syria, Lebanon, Palestine, and Iraq) in the immediate aftermath of World War I. These efforts were centred on the two largest sectors of the population to have survived the Catastrophe, orphans and familyless (or widowed) women. The essay examines the ideology of ‘national reconstruction’ and some of its internal contradictions. It pays particular attention to both Armenian women who married Muslims during the deportations and the children born of these marriages, as well as to Armenians who turned to prostitution to survive in the complex conditions prevailing in this period. The author makes use of extensive, previously neglected archival material: for example, correspondence by some of the principal actors, reports written during the process of locating and rounding up Armenian orphans, and documents that shed light on life within the walls of orphanages and women's shelters. The author assembled this archival material in Paris, Beirut, Aleppo, and Cairo, after surveying the contents of various archives. 相似文献
200.
Spring temperatures in the Sagehen Basin, Sierra Nevada, CA: implications for heat flow and groundwater circulation 总被引:1,自引:0,他引:1
Heat flow in the Sierra Nevada, CA, is low despite its young geologic age. We investigate the possibility that advective heat transport by groundwater flow leads to an underestimate of heat flow in the Sierras based purely on borehole measurements. Using temperature and discharge measurements at springs in Sagehen Basin, we find that groundwater removes the equivalent of approximately 20–40 mW m−2 of geothermal heat from the basin. This is comparable with other heat flow measurements in the region and indicates that, in this basin, at least, groundwater does transport a significant amount of geothermal heat within the basin. Additionally, we use estimates of the mean residence time of water discharged at the springs along with hourly temperature records in springs to provide constraints on groundwater flow depths within the basin. An analytical model based on these constraints indicates that the heat removed by groundwater may represent 20% to >90% of the total heat flow in the basin. Without better constraints on the regional hydrogeology and the depth of circulation, we cannot determine whether the heat discharged at the springs represents a change in the mode of heat transfer, i.e. from conduction to advection at shallow depths (<100 m) or whether this is a component of heat transfer that should be added to measured conductive values. If the latter is true, and Sagehen Basin is representative of the Sierras, basal heat flow in the Sierra Nevada may be higher than previously thought. 相似文献