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61.
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   
62.
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   
63.
居民家庭旅游消费行为初探   总被引:11,自引:0,他引:11  
居民家庭旅游行为是一种特殊的消费行为,本文根据长春市居民家庭消费行为的有关调查资料对影响长春市居民家庭旅游消费行为的因素进行了分析探讨,并说明了居民家庭旅游消费行为研究的重大意义。  相似文献   
64.
This essay argues for the moral necessity of retaining connections between the practices of representation and the ideal of authenticity. Using the example of racial representation, the author finds in the political philosophy of Charles Taylor and the cultural criticism of George Steiner resources for engaging in a creative dialogue with the history of our own tradition.  相似文献   
65.
Marginal and/or resistant consumption practices have been neglected in current geographical debates on consumption and retailing. This has resulted in partial and skewed theorizations of exchange within contemporary consumption. Consumption spaces such as car boot sales represent sites in which the conventions of the marketplace are suspended or abandoned, and replaced by forms of sourcing, commodity circulation, transaction codes, pricing mechanisms and value quite different from those which typify more conventional retail malls and department stores. Drawing on the anthropological literature on traditional and peasant markets, we argue that exchange within the car boot sale is socially, culturally and geographically embedded and we emphasize the intrinsic importance of fun and sociality to such activities. Marginal spaces such as the car boot sale offer both some important clues into the potential for rethinking marketplace dynamics, notably with respect to our understandings of value, and some intriguing possibilities for consumer politics.  相似文献   
66.
Research on labour markets has often focused on the economics of work location. Far less attention has been paid to how labour markets are constructed discursively. In this paper, I analyse how the creation of rival discourses concerning traditions of work were central elements in the efforts of two unions to structure local labour markets, in order to retain work for their members in the face of technological innovation. The struggle between the two unions centred on their abilities to construct rival discourses concerning the historical geography of work in the industry. These formed the basis for judicial interpretations concerning whether the actions of the dockers' union represented a legal work preservation action or an illegal work acquisition measure. Such interpretations shaped the subsequent evolution of work and labour markets in the industry. The ability of economic actors to shape discourse in their favour can be a powerful force in the regulation of local labour markets, and thus in the production of economic landscapes.  相似文献   
67.
Scholarship concerning the lives of enslaved African Americans in southern New England has shifted rapidly from outdated models of acculturation to conflict-driven models of domination and resistance. With the assumption of conflict as the outcome of all power relations, both economic production and historical contextuality have been overlooked, with slavery systems in New England simply equated with other regions of the Atlantic world, rather than compared and contrasted. This essay reconsiders contests over power in seventeenth- and eighteenth-century New England. Drawing on the work of Greene (1966), Piersen (1988), and others, I argue that the system of slavery in the region may represent an anomalous case in terms of the means of control or the means of resistance. By examining demographic patterns, economic production, and agricultural landscapes in Rhode Island's East Bay, I argue that there may be more to be learned from William D. Piersen's (1988, p. 143) concept of resistant accommodation as a middle ground between the two extremes of the theoretical spectrum. The essay concludes with suggestions for further research on the archaeology of African-American lives in the region.  相似文献   
68.
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   
69.
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   
70.
This paper summarizes recent archaeological research efforts, and changing perspectives, about the native history of the Caddo peoples who lived in the Caddoan Archaeological Area, which centers on the Great Bend of the Red River in Oklahoma, Texas, Arkansas, and Louisiana. Of particular focus are the origins and early developments of the Caddoan tradition, regional diversity, subsistence changes and agricultural intensification, sociopolitical dynamics, and Caddoan-European interaction.  相似文献   
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