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31.
西安城墙东门箭楼砖坯墙体风化因素研究报告   总被引:2,自引:2,他引:0  
论述了西安城墙东门箭楼的文化背景,实地考察了风化外状,并对风化外状进行了分类测试。通过对砖坯墙体材料进行化学全分析、X-射线衍射分析、吸水率测定(含他和系数)、冻融实验、泛霜实验、环境污染与水文气象监测资料的分析,研究了东门箭楼砖坯墙体不同风化外状的风化因素,同时对现代修缮用砖的理化性能及质量进行了评估。结果表明,温度的交替变化、水的冻结与融化使得砖坯裂解成碎块;干湿引起可溶盐的结晶与潮解以及自然界中的雨水、地面水或地下水、污染气体等通过溶解、水化、水解、碳酸化、氧化等方式,使得砖坯墙体表面酥碱粉化。同时说明研究适用于古建筑修缮使用的抗风化仿古青砖是当务之急。  相似文献   
32.
浑仪、简仪(以下简称两仪)在高PH、大气污染和日晒雨淋环境中的腐蚀是一种动态加速腐蚀过程。采用合成的双唑胺铜缓蚀剂和有机硅改性的甲基丙烯酸树脂,并分别复配成协同缓蚀剂群和含有增效稳定剂的封护剂。采用这两种材料和脱水后再防护的工艺,使带锈防护后的浑仪、简仪的腐蚀低于无污染大气中的速率。用电化学方法评价了防护技术的可行性,根据腐蚀与人工老化试验结果讨论了防护材料性能与腐蚀环境和带锈防护的关系,采用XPS分析方法探索了双唑胺比BTA更适用于两仪防护的原因。  相似文献   
33.
Much practically orientated environmental research is marked by a polarity between functionalist abstraction and ahistorical normative discourse. This paper seeks to bridge the divide between theoretical and empirical research through a case study of New York City's water supply. Current processes of socio-economic restructuring are leading to negative environmental consequences obscured by a failure to extend analysis beyond limited temporal, spatial or sectoral scales. Insights from regulationist theory show that a combination of fiscal, political and other developments are bringing about a wide-ranging reformulation of existing patterns of environmental regulation and service provision in the city. The power of the state is being radically diminished in relation to the power of capital and a plethora of different interest groups. A relatively simple centralized model of environmental regulation is being transformed into a complex decentralized pattern involving the emergence of new approaches to urban governance. Further research is needed on the contradictions between capitalist accumulation and environmental regulation at different spatial scales in order to link New York's changing role within the global economy to the declining political legitimacy and fiscal capability of the state to play an extensive role in environmental management.  相似文献   
34.
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   
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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   
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ABSTRACT

Early colonial officials and other newcomers frequently lamented the poor copra production in Wallis and Futuna, positioning the continued consumption of coconuts by Islanders as a waste. This article explores the contested uses of coconuts and the divergent visions of the islands’ landscape and future held by Islanders, officials, missionaries and traders during opening decades of French colony rule. In particular, a variety of incidents in the 1920s – from an indigenous co-operative to French expulsions – highlight the centrality of the emergent copra trade to the social and political status of these different groups. More broadly, however, the article demonstrates the failure of elites – both indigenous and newcomer – to substantially increase copra exports prior to the Depression in 1930, indicative of the limits of their ability to demand labour and transform the lifeways of the wider population.  相似文献   
39.
ABSTRACT

During a survey conducted by the authors in the eastern part of al-?arrah in Jordan in 2017,11. The term al-?arrah is used to refer to the basalt steppe-desert located in northern Jordan and southern Syria. a number of new Safaitic and Nabataean texts were found. Some of them mention events dated during the reigns of ?r?t and rb?l, others refer to the revolt of dm?y. Other Safaitic texts contain references to the Nabataeans. Three Nabataean graffiti were also found and are presented here. These sixteen new texts constitute a remarkable addition to the corpus of Safaitic and Nabatean texts found in this region.  相似文献   
40.
This article examines Rembrandt’s investigation of his own face in tandem with his studies of outcast populations in and around Amsterdam. While historians have titled these latter studies as “beggars,” I contextualize these figures within a history of migration, early modern Dutch globalization and shifting concepts of poverty and charity. Understanding these figures in a larger historical framework illustrates how Rembrandt used his own face to visualize the increasingly faceless populations passing through Amsterdam.  相似文献   
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