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91.
Anna Sandak Jakub Sandak Magdalena Zborowska Włodzimierz Prądzyński 《Journal of archaeological science》2010
Archaeological wood, as most of natural materials, is slowly decomposing on the archaeological site due to various biological factors. Rapid and accurate estimation of the degradation level is extremely important for optimal restoration and conservation. The goal of this research was to verify the effectiveness of Fourier transform near infrared (FT-NIR) spectroscopy for archaeometry. The important advantage of the NIR spectroscopy is its accuracy, simplicity and ability to perform very high number of tests without needs of any destruction to the workpiece. Five oak pieces of the archaeological wood collected from waterlogged sites in Poland have been used. Cellulose and lignin contents, as well as crystallinity and the degree of polymerization were measured with standard reference methods and compared to the contemporary wood. The near infrared spectra represent all the physical/chemical changes of the wood due to waterlogging. This technique was successfully validated in rapid estimation of the cellulose and lignin contents. The method explored in this research might be a novel tool assisting experts in evaluation of the degradation state of archaeological and historical wooden materials. 相似文献
92.
Paul Robbins Najeeb Jan Sarah Moore Anna J. Secor Joel Wainwright 《Political Geography》2010,29(6):343-351
93.
ABSTRACT The twenty‐first century will be one of intensified urbanization, on a scale never before experienced. How do urban systems and individual cities change and develop? The social sciences have many different approaches to analyzing the economic, social, and spatial dimensions of urban change. We inventory some of these approaches and their implications for public policy toward cities, urban change, and economic development. 相似文献
94.
Anna Newby 《Domes : digest of Middle East studies》2012,21(2):327-352
The interim Egyptian government's excoriation of U.S. support for nongovernmental organizations (NGOs) in the country has sparked a crisis that some analysts have called the worst deterioration of United States–Egypt relations in history. As Cairo's smear campaigns against the civil society community foment public mistrust among many Egyptians of NGO activity and foreign funding, U.S. policymakers and practitioners face new challenges in supporting civil society work in Egypt. For a number of reasons, however, Washington's assistance to Egypt should and almost certainly will continue, even if the environment for civil society activity in the country does not improve. Grantors and implementers must think seriously, therefore, about long‐term strategies for assisting civil society development in Egypt, which will require at least some coordination with a government that may be suspicious of U.S. efforts. By standing firm on red lines, improving public messaging in Egypt, carefully fostering local ownership of projects, remaining strictly neutral in identifying grantees and diversifying partnerships, distinguishing between short‐term foreign policy objectives and long‐term efforts to assist civil society development, and using varied democracy assistance tools appropriately, the United States can assist NGOs in Egypt in a way that gives them—and democracy—the best chance for success. 相似文献
95.
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
96.
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
97.
Martin van Gelderen 《History of European Ideas》2011,37(2):154-159
Through a discussion of Hugo Grotius’ conception of just war, this essay shows that within his critique of liberalism, Schmitt clashed with the very intellectual tradition he claimed to represent. Both historically and philosophically Schmitt's concept of the Ius Publicum Europaeum was a mirage. Indeed, his concept of the political was a rejection of the moral and civil philosophy that sees politics as the world of active citizens and commonwealths arguing with each other about fundamental questions of justice and equity. 相似文献
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100.
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