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331.
332.
The Conway granite of New Hampshire is a highly radioactive intrusive into which a 1-km deep borehole was drilled and continuously cored. The formation is composed of two major granitic units, the Osceola and the Conway; and it is cut by three lamprophyre dikes. The suite of rocks used in this paper contained eight granitic and two lamprophyre samples on which acoustic and strain measurements were performed over the pressure range of 1 atm. to 0.4 GPa. The Vp data were subjected to cluster analyses to determine what, if any, similarities in pressure-dependence existed among the samples. Three distinct similarity groupings were found: the lamprophyre dike rocks and two groups each of which contains samples from both granitic units. These groupings by Vp behavior were also found to correlate exactly with sample similarity groupings formed by dynamic and static moduli data, crack spectra, and rock texture. Such sample similarities in the functional forms of the pressure-dependence were found not to correlate with mineral modes nor with original in situ depth, but rather with grain size and the degree to which the mineral phases were homogeneously mixed. A consideration of the results suggests that for these rocks, grain size and mineral phase homogeneity exerted a dominant influence on crack population formation. Further, it appears that the exhumation and coring of these samples may have intensified the amount of cracking over that in situ but it did not necessarily introduce any individual distinct crack populations.  相似文献   
333.
This paper tracks changes in relative centralisation and relative concentration of poverty for the 25 largest British cities, analysing change for poor and non-poor groups separately, and examining parallel changes in spatial segregation. The paper confirms that poverty is suburbanising, at least in the larger cities, although poverty remains over-represented in inner locations. Suburbanisation is occurring through both the reduction in low income populations in inner locations and the growth non-poor groups in these places, consistent with a process of displacement. Relative centralisation of poverty has fallen more stronglythan relative concentration of poverty, as the outward shift of poorer groups leaves them still living in denser neighbourhoods on average. The paper also shows that spatial segregation (unevenness) declined at the same time although it remains to be seen whether this indicates a long-term shift to less segregated urban forms or a transitional outcome before new forms of segregation emerge around suburban poverty concentrations.  相似文献   
334.
Effective national and regional policy guidance on climate change adaptation relies on robust scientific evidence. This two-part series of papers develops and implements a novel scenario-neutral framework enabling an assessment of the vulnerability of flood flows in British catchments to climatic change, to underpin the development of guidance for the flood management community. In this first part, the sensitivity of the 20-year return period flood peak (RP20) to changes in precipitation (P), temperature (T) and potential evapotranspiration (PE) is systematically assessed for 154 catchments. A sensitivity domain of 4,200 scenarios is applied combining 525 and 8 sets of P and T/PE mean monthly changes, respectively, with seasonality incorporated using a single-phase harmonic function. Using the change factor method, the percentage change in RP20 associated with each scenario of the sensitivity domain is calculated, giving flood response surfaces for each catchment. Using a clustering procedure on the response surfaces, the 154 catchments are divided into nine groups: flood sensitivity types. These sensitivity types show that some catchments are (very) sensitive to changes in P but others buffer the response, while the location of catchments of the same type does not show any strong geographical pattern. These results reflect the range of hydrological processes found in Britain, and demonstrate the potential importance of catchment properties (physical and climatic) in the propagation of change in climate to change in floods, and so in characterising the sensitivity types (covered in the companion paper).  相似文献   
335.
This article examines the effect of the Kyoto Protocol's Clean Development Mechanism (CDM) on the international transfer of wind power technologies. The analysis is conducted using patent data from over 100 countries during the period 1988–2008. It is found that transfers from Annex I countries to non-Annex I countries are significantly affected by the contemporaneous establishment of projects under the CDM. However, when taking into account the cumulative effect of CDM projects, the effect is negative. Finally, the effect of domestic absorptive capacity in the host country is positive and significant. Because involvement with the CDM may increase the latter, this is an important area for further research.  相似文献   
336.
<正>In the last decade there has been a considerable effort to better understand the joint evolution of mafic and ultramafic magmatic systems and their deep mantle roots,through integrated petrological and thermo-barometric studies.Magma generation is regarded as the result of complex processes including melting,creation of channels for melt transfer,and interaction with the wall-rocks.Complexities in magmatic systems involve metasomatism and the creation of metasomatic fronts,branching and splitting of magma volumes during their evolution,and vat-  相似文献   
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