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71.
We present a new method for the obtention of the nuclear component of active galatic nuclei, that relies on the convolution
of a two-dimensional model of the host galaxy, based on seeing-free morphological parameters, with the seeing PSF. The procedure
overcomes some limitations of the methods currently in use and does not assume that the nucleus is unresolved.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Prey diversity of Homo sapiens in north Iberia exhibited shifts associated with climate warming after the Last Glacial Maximum, as deduced from animal remains obtained from Upper Palaeolithic caves in Asturias (northern Spain). Significant association of prey diversity and river proximity was found during adverse climate conditions, indicating opportunistic predation. A high increase of prey diversity was found when small animals (including fish) were taken into account in archaeological records, highlighting the importance of this type of prey in Palaeolithic diets. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
74.
Juana María Sanz Ángel de Miguel Irene de Bustamante Alberto de Tomás José Luis Goy 《Environmental Earth Sciences》2014,71(1):13-21
Conventional water treatments when downsized to cover the demands of small and scattered populations are costly and ineffective. In fact, many small towns cannot afford the high average treatment costs nor provide the skill and complex management requirements. Even when these facilities are available, waste water might not be properly treated. Land application system treatments (LAST) have been shown to be preferable on the basis of their technical effectiveness and financial viability. The recently approved Spanish regulations (RDL 1620/2007, pp 50369–50661) represent an opportunity for the implementation of well-designed LASTs. This paper presents an assessment methodology for the design of LASTs by combining technical, financial and location criteria. The method is applied to the design of LASTs to cover the water disposal demand of twelve municipalities located within the protected natural landscape, and surrounding areas of ‘El Rebollar’, Salamanca, Spain. 相似文献
75.
Takahito Mikami Tomoya Shibayama Miguel Esteban Koichiro Ohira Jun Sasaki Takayuki Suzuki Hendra Achiari Teguh Widodo 《Natural Hazards》2014,71(1):851-870
On October 25, 2010, a large earthquake occurred off the coast of the Mentawai islands in Indonesia, generating a tsunami that caused damage to the coastal area of North Pagai, South Pagai, and Sipora islands. Field surveys were conducted soon after the event by several international survey teams, including the authors’. These surveys clarified the tsunami height distribution, the damage that took place, and residents’ awareness of tsunamis in the affected islands. Heights of over 5 m were recorded on the coastal area of the Indian Ocean side of North and South Pagai islands and the south part of Sipora island. In some villages, it was difficult to evacuate immediately after the earthquake because of the lack of routes to higher ground or the presence of rivers. Residents in some villages had taken part in tsunami drills or education; however, not all villages shared awareness of tsunami threats. In the present paper, based on the results of these field surveys, the vulnerability of these islands with regards to future tsunami threats was analyzed. Three important aspects of this tsunami disaster, namely the geographic disadvantage of the islands, the resilience of buildings and other infrastructure, and people’s awareness of tsunamis, are discussed in detail, and corresponding tsunami mitigation strategies are explained. 相似文献
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Thermal expansion differences between minerals within rocks under insolation have previously been assumed to drive breakdown by means of granular disaggregation. However, there have been no definitive demonstrations of the efficacy of this weathering mechanism. Different surface temperatures between minerals should magnify thermal expansion differences, and thus subject adjacent minerals to repeated stresses that might cause breakdown through fatigue failure. This work confirms the existence of surface temperature differences between minerals in granitic rocks under simulated short-term temperature fluctuations so as to discriminate their potential for initiating granular disaggregation. The influence of colour, as a surrogate for albedo, and crystal size, as a function of thermal mass are specifically identified because of their ease of quantification. Four rock types with a range of these properties were examined, and subjected to repeated short-term temperature cycles by radiative heating and cooling under laboratory conditions. Results show that while albedo is the main control for overall and individual maximum temperatures, crystal size is the main factor controlling higher temperature differences between minerals. Thus, stones with large differences of mineral sizes can undergo magnified stresses due to thermal expansion differences. 相似文献
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Pérez-López R Nieto JM López-Cascajosa MJ Díaz-Blanco MJ Sarmiento AM Oliveira V Sánchez-Rodas D 《Marine pollution bulletin》2011,62(2):405-411
This study reports the annual amount of heavy metals discharged by industrial activity into the estuary of the Ría of Huelva (SW Spain). The findings showed that the discharged metals found in highest amounts were Fe (11 t y−1), Zn (3.4 t y−1) and Mo (0.88 t y−1). There were other metals with high pollutant charge, such as Ti (232 kg y−1), As (228 kg y−1), Ni (195 kg y−1), Pb (100 kg y−1), Cr (39 kg y−1) and Cd (33 kg y−1). These results were compared with pollutants transported via the Tinto and Odiel rivers from abandoned mining activities in the Iberian Pyrite Belt (IPB), and it was deduced that the amounts spilled exclusively by industries were less than 1% in relation to the total discharge. Hence, the treatment of residues from the IPB should be the priority goal to improve water quality in the estuary. 相似文献
80.