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41.
Danuta Michalska Anna Pazdur Justyna Czernik Małgorzata Szczepaniak Marta Żurakowska 《Geochronometria》2012,40(1):33-41
Lime mortars may contain carbon from different origins. If the mortars are made of totally burnt lime, radiocarbon dating yields the true age of building construction. The presence of carbonaceous aggregates gives the so-called dead carbon effect, which may generate older ages. Another source of carbon is charcoal present in mortars. An attempt has been made to apply the radiocarbon method to mortars of archaeologically estimated age from the Dead Sea region. Petrographical analyses of these samples show the carbonaceous character of the binder and large amounts of limestone aggregate. Determination of the mineral composition of the mortars and comparison with the geology of the surrounding, allows the provenance of the raw materials to be identified. They probably represent the Cretaceous rocks of the Judea Group. Separate radiocarbon dates were made on bulk mortar samples, binder, charcoal fragments and separated fractions from mortars. In the case of binder-aggregate mixture the reservoir effect correction has been applied. 相似文献
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Abstract: This paper is concerned with the social and spatial processes adopted by workers who face problems at work. Using interview data with minority ethnic workers in three local communities in London, the paper explores the mechanism people use to seek help and advice and what resources are available from local community organisations. Key findings suggest that many workers, both unionised and non‐unionised find themselves isolated and unable to access the support they need. 相似文献
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We present the first analysis of the influence of climate change on carbon and oxygen isotope fractionation factors for two saccharides (glucose and α-cellulose) of pine wood. The conifers grew in the Niepo?omice Forest in Poland and the annual rings covered a time span from 1935 to 2000 AD. Glucose samples from acid hydrolysis of α-cellulose were extracted from annual tree rings. The carbon and oxygen isotope fractionation factors between glucose and α-cellulose were not stable over time. The mean value for the carbon isotope fractionation factors between glucose and α-cellulose was greater than unity. The mean value for the oxygen isotope fractionation factors between glucose and α-cellulose was lower than unity. We established, with respect to climate change, the significance of the interannual and intraannual variation in the carbon and oxygen isotope fractionation factors between both saccharides. We used moving interval correlation results for May of the previous year through September of the current year using a base length of 48 years. The relationship with summer temperature is the main climate signal in the carbon isotope fractionation factor between glucose and α-cellulose. The relationship with autumn sunshine is the main climate signal in the oxygen isotope fractionation factor between glucose and α-cellulose for the tree ring chronology. 相似文献
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Anna M. Cienciala 《国际历史评论》2013,35(1):129-145
The Activities of Polish Communists as a Source for Stalin's Policy Towards Poland in the Second World War 相似文献
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Emilie-Pauline Gallié Anna Glaser Valérie Mérindol Thierry Weil 《European Planning Studies》2013,21(10):1653-1675
This article explores the diversity of 66 French competitiveness clusters, which were all accredited in 2005 according to the same specifications, by characterizing the initial context in which they emerged and taking a close look at the link between this initial context and their current performance. Since French competitiveness cluster policy is based on state co-funding of R&D projects, we establish a typology based on a multiple component analysis and a hierarchical ascending classification of the R&D potential of the cluster's territory, the respective R&D efforts of companies and academic laboratories, the kinds of actors setting up the cluster and their pre-existing relationships. We then measure the differences among the five classes relating to their clusters' capacity to obtain state funding for their projects. Our results show that initial context can partially explain competitiveness clusters' performance. Competitiveness clusters in territories possessing significant R&D resources, and involving large companies capable of organizing projects, are the most efficient in obtaining state funding. In contrast, competitiveness clusters without prior cooperation experience perform poorly. 相似文献
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Drawing on theories of space, gender, and participatory learning, central concepts in feminist pedagogy, the author designed a university-level general-education course that took the Twenty-Five Ladies Tomb in southern Taiwan as the focus of a field study and class discussion. This local gendered site, which commemorates a 1973 ferry accident that killed 25 unmarried young women working in Kaohsiung, raises issues about patriarchy in Taiwan, gender inequities in traditional Han customs, and women's labor. The course relied on guided class discussions and focus-group discussions, culminating in a visit to the site. Face to face with the researched, the author not only built an inclusive and supportive relationship with students in the classroom, but also put her researcher's reflexivity into teaching practice. Research results indicate that the freedom of the class discussion format succeeded in breaking down the logic of binary opposition that accompanies the traditional gender duality of male/female. Avoiding a top-down teaching style also minimized students' resistance to perspectives emphasizing gender equality. 相似文献