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981.
Archaeological wood is usually severely degraded. The Norwegian Viking Age Oseberg find exemplifies problems arising due to past conservation treatments and the need for new types of preservatives. Phenol formaldehyde (PF) has been investigated as a consolidant for alum‐treated wood. X‐ray tomography has revealed that it is possible to obtain a porous structure inside the wood, ensuring ethical acceptability by allowing re‐treatment. In order to understand the curing mechanics, the kinetics of the initial condensation reaction were elucidated at room temperature. It was found that a second‐order reaction using both phenol and formaldehyde concentrations is the most probable mechanism.  相似文献   
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Abstract

In recent years, popular protest in China has emerged from a state of near-invisibility. Drawing on a diachronic analysis of news media coverage, this paper traces how a number of major protest events gradually entered the Chinese media’s spotlight and came to be portrayed in an increasingly protester-sympathising fashion over the course of the Hu-Wen administration. It argues that these changes were triggered by structural transformations of the Chinese public sphere, but underlines that deliberate policy choices by the political leadership served as a crucial agent of change. Facing proliferating unrest and an increasingly unimpeded flow of information, the central authorities have gradually shifted propaganda policy from a suppressive to a more proactive approach. They have thereby created critical opportunities for Internet users and investigative journalists to push the envelope further towards protester-sympathising accounts. The development is significant as there are good reasons to surmise that increased media coverage has exacerbated the dynamics of popular contention. Theoretically, it deserves to be noted that non-inevitable choices by an authoritarian leadership have led to an outcome in which media coverage of citizens who challenge the state on the streets has become substantially more frequent and positive than before.  相似文献   
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Mount Nemrut is a 2,206 m high mountain located in Adiyaman, Turkey. A number of monumental statues, a 50-m high tumulus, and a lion horoscope were constructed at the top of the mountain by King Antiochos I (69–36 bc) of the Commagene Kingdom. The site was included in the UNESCO World Heritage List in 1987 due to its unique character. However, the limestone statues located on both the east and the west terraces of the site are getting deteriorated. This study investigates the weathering of the limestone at Mount Nemrut based on field and laboratory studies. It is found that the dissolution occurs along microcracks developed in the limestone during geological time. It is more pronounced in the east terrace where freezing-thawing cycles are more than the west terrace. Furthermore, dissolution is more effective for the faces of the statues exposed to direct atmospheric contact. Due to harsh atmospheric conditions with dominant wetting-drying and freezing-thawing processes at the site, it is recommended that direct rain and snow contact with the statues should be minimized.  相似文献   
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Human-induced global threats are compelling many anthropologists to rethink roles, methods, and paradigms and engage in public debate and action on energy policies, extraction processes, commodity chains, and consumption. Laura Nader's Energy Reader embodies her decades-long engagement as a catalyst for public debate on U.S. energy issues. Tanja Winther's Impact of Electricity exemplifies ethnography informing development practice. Strauss and colleagues’ Cultures of Energy reflects diverse approaches seeking to build cultural understandings to inform energy choices. There remains a need for collaboration with anthropologists embedded in energy-related agencies—positioned where they can leverage anthropological knowledge to push policy envelopes.  相似文献   
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The thermoluminescence dating method was applied to 77 heated flints from the Mousterian layers of Hayonim Cave in order to provide a precise TL-based chronology for this important Levantine sequence. A detailed dosimetric study was performed by using 76 dosimeter capsules and revealed strong spatial dose-rate variations. In parallel, Fourier transform infrared spectrometry enabled the identification of various mineral assemblages in the sediments of the cave and to localize the boundaries of these assemblages. By comparing these two data sets, it is shown that low dose-rate values (∼500 μGy/a) are systematically recorded in areas where the calcite-dahllite (CD) assemblage is preserved, whereas higher values (up to 1300 μGy/a) are associated with the leucophosphite, montgomeryite, variscite and siliceous aggregates (LMVS) assemblage. The dosimetric and mineralogical information was combined in order to assess, where possible, the dose-rate experienced by each flint during its burial. Some of the flint samples analyzed were too close to mineral assemblage boundaries and were therefore discarded. This rigorous selection led to TL ages ranging from 230 to 140 ka for the lower part of the Mousterian sequence (layers F and Lower E), which contains lithic industries characterized by blade production using the laminar method.  相似文献   
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