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11.
ABSTRACTThe preservation of artefacts in museum collections is profoundly affected by fluctuations in temperature and, especially, relative humidity (RH). Since the late nineteenth century, many studies have been carried out on the best way to control hygrothermal conditions. In old buildings located in maritime temperate climate zones (such as Portugal) with strong thermal inertia, and which have low ventilation rate (relative to the volume and number of visitors), daily and seasonal hygroscopic inertia may help to assure the maintenance of RH stabilization conditions. The use of expensive active systems may be minimized through the passive behaviour of internal finishing building materials. This work presents the results of an experimental laboratory study conducted in a flow chamber to demonstrate the enormous potential of hygroscopic materials in stabilizing interior relative humidity. Based in these results and in-situ monitoring in a museum housed in a building, located in Porto, with a typical construction of the 1950s (granite masonry and reinforced concrete slabs), a numerical analysis was done to quantify the influence of hygroscopic materials in stabilizing the interior relative humidity. 相似文献
12.
AbstractIn an economic climate when colleges can no longer presume that legislators see institutions of higher learning as tacit public goods, institutions around the country are facing budget cuts. This article presents a case study of the experience of a mid-sized public state university and its Library in a budget crisis undergoing a university-wide program prioritization process. The authors review the process of writing three reports on the Library’s value, along with the approach to engaging staff in the process including a retreat. This article raises questions about what every library should consider assessing and provide tools for libraries navigating similar terrain. 相似文献
13.
U. Casellato F. Fenzi P. Guerriero S. Sitran P. A. Vigato U. Russo M. Galgani M. Mendera A. Manasse 《Journal of Cultural Heritage》2003,4(4):337-353
A significant number of archaeological finds of the 13th–16th century from the Tuscan sites of Germagnana and Gambassi in Valdelsa—FI, was studied by different physico-chemical investigations (SEM–EDS, ICP, Mössbauer spectroscopy, XRD, XRF, TG-DTA) in order to contribute to clarify the production methodology and the pre-industrial glass manufacture technology. The studied samples are mainly non-vitreous finds as production waste, refractory materials, crucibles and raw materials; also vitreous finds as frits, skims, glasses (glass masses, glass working waste and finished products) have been taken into consideration. The obtained petrographic and physico-chemical data strongly suggest that both Gambassi and Germagnana glass manufactures were strictly connected with the sources of vitrifiable materials, situated in Tuscan sand quarries. In particular a comparison between sands from the neighbouring quarries and appropriate finds of the two archaeological sites evidences that the employed vitrifiable materials possibly belong to La Casina La Cava resort. The archaeological classification, based on macroscopic observation and stratigraphic position, was compared and verified with the scientific classification of the examined finds of Germagnana and Gambassi sites based on their composition, morphology and physico-chemical properties. 相似文献
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浅谈如何上好艺术体操选修课 总被引:1,自引:1,他引:0
对普通高校艺术体操选修课教学从形体姿态的培养、教学成套动作的编排,音乐的选择及口令、手势的运用等,进行了分析探讨. 相似文献
16.
David C. Berliner 《Journal of Personnel Evaluation in Education》1990,4(1):75-90
17.
论高校体育教学中学生创新思维能力的培养 总被引:3,自引:0,他引:3
通过树立现代体育教学观念、优化体育课堂教学、优选体育教学法等几个方面论述了学生创新思维能力的培养。 相似文献
18.
浅析足球运动员意志品质及培养方法 总被引:1,自引:1,他引:0
阐述了足球运动中意志品质的作用和地位、培养足球运动员意志品质的意义及各种方法. 相似文献
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采用录像观察法、数理统计法和文献资料法对中国队在亚洲杯期间主力阵容与98世界杯前3强主力阵容变化进行比较研究.结果表明:98世界杯前3强队伍主力阵容在比赛期间基本保持完整,而中国队主力阵容在最后一场比赛中极不完整.研究认为:影响中国队比赛阵容完整性的主要因素是战斗性减员和非战斗性减员.建议国家队应配备体能教练和心理学、运动医学、营养学专家;加强运动员的自我保护意识,使运动损伤最小化;合理运用技术动作减少红黄牌的发生. 相似文献