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61.
甘肃酒泉、嘉峪关壁画墓霉菌分离鉴定与防治研究   总被引:1,自引:1,他引:0  
通过对墓葬壁画霉菌分离鉴定,筛选出合适的防霉材料,对壁画进行防霉处理是解决未搬迁尚很潮湿壁画墓科学保存问题的一个重要方面。  相似文献   
62.
The Revolution of 1959 brought forth changes in the mission, theoretical orientation, and organization of archaeology in Cuba and created a role for, and constraints on, the profession that are unique in the Western Hemisphere. This paper draws upon examples from substantive field and laboratory research to examine the methods and theoretical perspectives of Cuban archaeology since the Revolution, focusing on the period from 1962 until the collapse of the Soviet Union. Archaeological practice during the Revolutionary period in Cuba has reflected the aims of the Revolutionary government, the influence of Soviet archaeology, the legacy of pre-Revolutionary approaches in North American archaeology, and the Cuban sense ofpatria.  相似文献   
63.
The chronology of the period is briefly considered in the light of the dendrochronological results which have appeared in recent years. Patterns of settlement history in different parts of the area are then examined, and it is suggested that in some of them the late fourth millennium was a period of population decline which was not reversed until the Early Bronze Age, 1000 years later. Detailed information about specific local occupation patterns is provided by recent work on the circum-Alpine lake villages. Changes in cultural patterns during the period, especially the appearance of the Corded Ware, are discussed and explanations of them reviewed. It is argued that changing patterns of gender relations were a major feature of the period, linked to processes which eventually led to the development of small-scale chiefdoms. The development of copper and bronze metallurgy and its connection to these processes are discussed.  相似文献   
64.
高颐阙是东汉晚期的红色砂岩的建筑物。位于四川省雅安市。阙檐东面残缺.导致日晒雨淋加剧,苔藓丛生,从而引起严重风化。为此,对残损阙檐进行了修复。根据高颐阙的结构.雅安市的气候特征及阙石的化学组成和物理性质.讨论了薄片检查和 X 衍射分析的结果、修复残缺阙檐的理论基础以及计算、修复的程序和效果。  相似文献   
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In the last decade, conversations around queering of GIScience emerged. Drawing on literature from feminist and queer critical GIS, with special attention to the under‐examined political economy of GIS, I suggest that the critical project of queering all of GIS, both GIScience and GISystems, requires not just recognition of the labour and lives of queers and research in geographies of sexualities. Based upon a queer feminist political economic critique and evidenced in my teaching critical GIS at two elite liberal arts colleges, I argue that the “status quo” between ESRI and geography as a field must be interrupted. Extending a critical GIS focus beyond data structures and data ethics, I argue that geographic researchers and instructors have a responsibility in queering our choice and production of software, algorithms, and code alike. I call this production and choice of democratic, accessible, and useful software by, for, and about the needs of its users, good enough software.  相似文献   
69.
The original fineness of coins is very important information that can help us to understand the commercial situation in a wide historical context. This paper deals with a comparison of analytical methods suitable for the evaluation of the actual and original fineness of coins based on a detailed case study of a medieval coin sample. Both non‐destructive (i.e., scanning electron microscopy/energy‐dispersive X‐ray spectroscopy, X‐ray fluorescence, atomic force microscopy and hydrostatic weighing) and destructive (i.e., inductively coupled plasma – mass spectrometry and the Volhard titration method) techniques were used. The original fineness can be also deduced from knowledge of the internal structure of the coin (limited miscibility of copper and silver). A new analytical method based on a combination of a micrograph of the metallographic cross‐section with consequent image analysis was developed for determination of the original fineness. The proposed approach is relatively simple and provides reliable values. Sample heterogeneity and its impact on the determination of fineness are also discussed.  相似文献   
70.
G. Hervé  P. Lanos 《Archaeometry》2018,60(4):870-883
We present a new curve of the directional secular variation of the geomagnetic field in Western Europe between 1500 bce and 200 ce . Its computation relies on a Bayesian framework. The fast secular variation during the Late Bronze and Early Iron Ages makes archaeomagnetic dating efficient with a respective precision of 150–200 and 60–100 years during these periods. The Bayesian method also provides posterior date distributions that refine the dating of reference data, especially during the period of the Hallstattian radiocarbon plateau. Archaeomagnetism becomes a valuable alternative to radiocarbon and will help to improve the archaeological chronologies.  相似文献   
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