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The spectre of American decline is once again animating both observers and practitioners of US foreign policy. The global financial crisis, a faltering American economy and continued costly and controversial military engagements overseas have been presented as conclusive proof that American foreign policy will soon lack the resources needed to sustain its previous international hegemony. Arguments of domestic weakness have been linked to analyses of the economic vitality of America's competitors to demonstrate a seemingly watertight case for relative decline. The inexorable rise of China has been presented from various quarters as evidence that the American era will soon be drawing to a close. Yet, such declinist arguments continue to suffer from fundamental weaknesses, overestimating the likely future strength of America's rivals while concurrently downplaying the capacity of the US to rejuvenate its economy and thus revivify its liberal universalist creed. The most interesting development in this regard has been the sudden resurgence of the US energy sector. Written off less than a decade ago as being in terminal decline, the American oil and gas industry has staged a remarkable recovery. Vast reserves of shale gas and accompanying tight oil offer the potential to aid the revival of the American economy, with some forecasts pointing to US energy self‐sufficiency within two decades. Notions of US relative decline may yet prove premature. The geopolitical impact of American energy self‐sufficiency is likely to be very significant, making an important contribution to a reversal of the US trade deficit, a revival of America's industrial base, and the possibility of a corresponding relative decline in power for conventional fossil fuel exporters.  相似文献   

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There is considerable interest in the use of thick argillaceous geologic formations to contain nuclear waste. Here, we show that diffusion can be the controlling transport process in these formations and diffusional time scales for δ18O and δ2H in water, dissolved He, and Cl transport in shale‐dominated aquitards are typically over 106 years, well exceeding the regulatory requirements for isolation in most countries. Our scientific understanding of diffusive solute transport processes through argillaceous formations would benefit from the application of additional isotopic tracers (e.g., using new 4He sampling technology), multidimensional diffusive‐dispersive modeling of groundwater flow and diffusive‐dispersive solute transport over long geologic time scales, and an improved understanding of spatial heterogeneity as well as time‐dependent changes in the subsurface conditions and properties of argillaceous formations in response to events such as glaciation. Based on our current isotopic and geochemical understanding of transport, we argue that argillaceous formations can provide favorable long‐term conditions for isolating nuclear wastes.  相似文献   

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The identification of the organic residues preserved in archaeological materials yields good insights into understanding food production, trade and consumption. Wine is one of the most important beverages produced, traded and consumed in the Mediterranean area. Consequently, it is important to identify its presence in ancient materials. Nevertheless, the identification of wine markers is still an object of discussion. We present here the results obtained from analysing different materials using gas chromatography/mass spectrometry (GC/MS), which allowed for the identification of tartaric acid and other markers of wine. The method was first tested on experimental and traditional materials that have been used until recently to store and/or produce wine and was then used for investigating archaeological materials. The experiments also involved the degradation of wine through cooking, drastic heating and burial for seven years. The results from the analysis of ceramic and plaster materials are discussed.  相似文献   

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Planning systems developed through the period of ‘normative’, ‘third way’ neoliberalism were critiqued as being ‘post-political’. Planning systems were developed that bypassed political conflicts through technocratic and consensus-seeking approaches following a so-called ‘end of history’ in which left/right ideological conflicts were deemed settled. Following the North Atlantic financial crisis of 2007/8 though, scholars have begun to question whether this is a suitable critique of planning, and state institutions more generally, as political and economic conditions shift. This paper examines a case of an exemplar post-political planning system: England. The paper identifies three key logics of a ‘post-political regime’ for planning: techno-managerialism, consensus and participation. Through an analysis of texts and interviews of contested planning decisions made over shale gas fracking sites, this paper shows a ‘post-political regime’ for planning facing a crisis of legitimacy as it is challenged by an anti-fracking movement and reactionary interventions from central government. The paper provides an institutional level analysis of the crisis of post-political planning, which has lost legitimacy amidst the slow collapse of normative neoliberalism.  相似文献   

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Plant and particularly non-wood forest products have played an important role in the evolution of human cultures all over the world, as source of food but also of raw substances fulfilling material, spiritual, and medicinal requirements. Plant exudates and particularly dammar resins (Dipterocarpaceae family) were widely used in the past in Asia notably as waterproofing and caulking materials. This study focuses on the GC–MS chemical characterisation of freshly collected dammars and establishes new molecular parameters enabling discrimination between dammars and other types of plant resin, whatever their botanical origin. Such analyses provide clues for a precise identification (taxonomy, occurrence of other material in addition to the resin, alteration state) of unknown resinous material discovered in archaeological contexts. The value of our approach is illustrated by the taxonomic characterisation of two samples collected in jars from the Brunei wreck and a Chinese junk lost more than 40 km off the Sultanate of Brunei during the end of the fifteenth century or the early beginning of the sixteenth century.  相似文献   

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The analysis of the composition of organic residues present in ancient pottery are an important source of information for archaeologists. The chemical characterisation of these materials gives information on diets, habits, technologies and original use of the vessels.  相似文献   

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