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María Barajas Enrique Lima Victor Hugo Lara Javier Vzquez Negrete Cristina Barragn Claudia Malvez Pedro Bosch 《Journal of archaeological science》2009,36(10):2244-2252
A huge monolithic piece corresponding to the first years of the sixteenth century has been discovered in Mexico City. It represents the earth goddess Tlaltecuhtli. The preservation of such a magnificent piece is imperative. Therefore, the surface has to be characterized and the interaction of consolidants with the rock has to be understood.Some of the consolidation methods are impregnation of the mineral with nopal or silicic acid derivatives. In this work we compare the physico-chemical effects of organic and inorganic consolidants. Original and impregnated samples are characterized with a series of original techniques: X-ray diffraction, nuclear magnetic resonance, nitrogen adsorption and small angle X-ray scattering. Fractal dimension, specific surface area and pore size distribution clearly differentiated the samples. The organic materials, nopal gum or slobber, cover the mineral particles with a smooth layer. The KSE solutions react and lead to microporosity. 相似文献
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Maria Rosa Guasch-Jané Cristina Andrés-Lacueva Olga Jáuregui Rosa M. Lamuela-Raventós 《Journal of archaeological science》2006
Ancient Egyptians were buried with the most precious food and drink as sustenance for their afterlife. One of these was Shedeh, the most valued and appreciated beverage in ancient Egypt. The botanic origin of Shedeh remains unclear as no mention of its raw material has survived. Some scholars have proposed that Shedeh was a pomegranate wine, while others, a grape wine. Presented here is the first ever analytical evidence of Shedeh's origin through the analysis of a sample of a residue from an extraordinarily well preserved Shedeh amphora from King Tutankhamun's collection. The previously developed LC/MS/MS wine markers method for archaeological samples was used and our results reveal Shedeh had a red grape origin. 相似文献
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Do Regions Make a Difference? Regional Innovation Systems and Global Innovation Networks in the ICT Industry 总被引:1,自引:0,他引:1
Cristina Chaminade 《European Planning Studies》2015,23(2):215-237
Access to global innovation networks (GINs) has been unequal across the regions of the world. While certain regions are considered knowledge hubs in GINs, others still remain marginalized; this points to the role of regional innovation systems (RISs) in the emergence and development of GINs. Using firm-level data collected through a survey and case studies in 2009–2010, this paper systematically compares the patterns of global networks in the information and communications technology industry in a selection of European, Chinese and Indian regions. The results show that GINs are more common in regions which are not organizationally and institutionally thick, suggesting that GINs may be a compensatory mechanism for weaknesses in the RIS. 相似文献
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With the violent clashes that took place in May 2010 during the attempt by the Free Gaza movement flotilla to break the blockade of the Gaza Strip, the remarkable strength of pro‐Palestinian networks became globally apparent. Drawing on an ethnography of political activism in the Israeli‐Palestinian space, we suggest that the striking visibility of these networks does not exclusively derive from the prominence of the Israeli‐Palestinian conflicts, but is also a consequence of the activists’ ability to produce innovative forms of sociality. However, some of the approaches taken can exist in problematic relation to the experiences of people who live with the conflict. In this context, the issue is not so much the precise relationships between indigenous ‘truths’ in Palestine and their foreign representations, but the way in which encounters redefine the conflicts that activist networks seek to represent. 相似文献
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