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991.
JEAN‐YVES HAINE 《International affairs》2015,91(5):991-1008
The transatlantic partnership needs to be reassessed. Since the end of the Cold War, Europe has chosen to bandwagon with the United States and to outsource its security to Washington. Bandwagoning has serious consequences when the use of force is at stake: it may lead to entrapment, where weaker allies may be involuntarily dragged into a conflict. It may also lead to abandonment, where the dominant ally may choose to discard their vital security concerns. With the evolution of the international system towards a multipolar configuration, this strategy of bandwagoning is becoming increasingly costly for Europe while the dominant power, the United States, is progressively confronted by other competitors at the systemic level. These classic dilemmas attached to an asymmetric partnership are exacerbated in a multipolar configuration. In particular, the abandonment scenario may become more and more frequent precisely because there is competition—and thus potential costs—at the international level: the United States may leave Europe alone, not by choice but by necessity. The current crisis in Ukraine illustrates this shift: while some American leaders were keen to escalate the conflict by arming Ukraine, the Obama administration's commitment to the defence of Europe has been minimal and it has largely delegated the management of the crisis to the Europeans themselves. Washington had other and more important priorities. Strategic autonomy is not an option for Europe; it has become a reality, a Gaullist moment where Europeans will have to learn to think and act strategically for themselves. 相似文献
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RHX Dating: measurement of the Activation Energy of Rehydroxylation for Fired‐Clay Ceramics 下载免费PDF全文
In rehydroxylation (RHX) dating, the activation energy of the rehydroxylation reaction is required first in the estimate of a material's effective lifetime temperature (ELT), and second to correct the RHX rate constant obtained at a given measurement temperature to that at the ELT. Measurement of the activation energy is thus integral to the RHX methodology. In this paper, we report a temperature‐step method for the measurement of activation energy and develop fully the underlying theoretical basis. In contrast to obtaining the activation energy from a series of separate experiments (each of which requires the sample to be dehydroxylated prior to measuring the RHX rate constant), the temperature‐step method not only requires a single dehydroxylation at 500°C but also eliminates repeated acquisition of Stage I data, which are not required for dating purposes. Since the first temperature step is set to correspond to the temperature at which a dating determination is carried out, the measurement of rate constants at higher temperatures simply becomes an extension of dating. Consequently, the logistics of obtaining the activation energy of rehydroxylation are greatly simplified. 相似文献
993.
A Preliminary Study on the Loss of Iron and Arsenic in the Re‐Melting of Iron‐Bearing Arsenical Copper 下载免费PDF全文
Re‐melting experiments were conducted with specimens made of high‐arsenic copper alloys containing lead, iron and sulphur. The melting treatment at 1000°C in ambient conditions for 5 min was found to cause an almost complete removal of iron and sulphur along with a notable reduction of arsenic levels. Evidence was found that the preferential oxidation of iron and arsenic was responsible for this change in composition. The treatment also brought about perfect dissolution of speiss particles scattered throughout the original specimen, suggesting the possibility of the addition of speiss to molten copper for the production of arsenical copper. 相似文献
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Early pan‐Arabism in Egypt's July revolution: the Free Officers' political formation and policy‐making, 1946–54 下载免费PDF全文
Reem Abou‐El‐Fadl 《Nations & Nationalism》2015,21(2):289-308
Between 1952 and 1970, Gamal Abdel Nasser and Egypt's Free Officers Movement established the paradigmatic pan‐Arabist revolution from above. Yet it has become something of a cliché to maintain that the Free Officers had no blueprint of action before seizing power and that they later instrumentalised pan‐Arabism in their foreign policy, thinly veiling their actual commitments to Egyptian nationalism and imperialism. By contrast, this contribution underlines the impact of the British colonial context on the Free Officers' political formation and their early identification with pan‐Arabism in turn. Drawing on pamphlets, speeches, media output and memoirs, it shows that the Free Officers developed a distinctive form of anticolonial nationalism that emphasised social justice and invoked overlapping Egyptian and Arab identities. Their aspirations for liberation thus entailed a connected foreign policy and nation building programme in which pan‐Arabism was a prime – and early – component. 相似文献
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Practical Knowledge in the Viking Age: the use of mental templates in clinker shipbuilding 下载免费PDF全文
It has long been recognized that ships built according to the Nordic clinker tradition during the Viking Age were conceived and constructed simultaneously by eye, in a shell‐first manner, and using rules‐of‐thumb to control both the longitudinal and transversal shape of the hull. While a lot of attention has been paid to the conceptual definition of the keel and stems, far less research has explored how such rules would have worked while planking the hull. Two cargo‐ships, Skuldelev 3 and Skuldelev 1, are used to argue for pre‐design and the use of mental templates. This highlights a cognitive dimension of practical knowledge, in particular how it was accumulated, stored and transmitted. 相似文献