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11.
ABSTRACT

The 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   
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Young children show social preferences for resource-rich individuals, although few studies have explored the causes underlying such preferences. We evaluate the viability of one candidate cause: Children believe that resource wealth relates to behavior, such that they expect the resource rich to be more likely to materially benefit others (including themselves) than the resource poor. In Studies 1 and 2 (ages 4–10), American children from predominantly middle-income families (= 94) and Indian children from lower income families (= 30) predicted that the resource rich would be likelier to share with others than the resource poor. In Study 3, American children (= 66) made similar predictions in an incentivized decision-making task. The possibility that children's expectations regarding giving contribute to prowealth preferences is discussed.  相似文献   
14.
ABSTRACT

This forum brings together food, (in)security, and communication. The authors participating in this forum center communication as both process and tool for understanding, mitigating, and making meaning of food (in)security. The nine authors together discuss the role of communication in food (in)security, the central challenges for scholars and practitioners working on food (in)security, and the creative possibilities and impacts influencing the future of food (in)security. The forum produces a call for applied scholars to re-imagine communication frameworks in order to make meaningful differences in their communities.  相似文献   
15.
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   
16.
体育真义论   总被引:7,自引:0,他引:7  
首先对体育能够增强体质,祛病保健,益寿延年的传统信条提出质疑,通过对体育的基本属性和两大种差特点的分析,提出体育是旨在强化体能的非生产性人体活动这一新概念。  相似文献   
17.
论高校体育教学的创新与大学生负性情绪的调控   总被引:1,自引:0,他引:1  
关注学生的心理问题,是创新高校体育教学的又一核心问题。笔者拟透视“情绪”这一视角,来分析当前高校体育教学对大学生情绪的影响,以求切准大学生带有社会性的整体情绪状态,来创新高校体育教学,以实现大学生身、心、群的全面发展。  相似文献   
18.
“说课”是授课者在有限的时间内,将一节体育课的教学内容、方法,课的组织形式、练习步骤以及场地、器材等运用情况,用简练准确的语言并配合清晰、简单的动作示范向听课者展现出来。实习生课前采用“说课”,能使各教学环节在头脑中加深印象,加快向教师角色意识转换的速度,有利于教学基本功的掌握,此方法具有可操作性和实用性。  相似文献   
19.
高原训练的生物学效应   总被引:2,自引:1,他引:1  
高原训练对人体有着复杂的生理学效应和训练学效应,是提高运动员运动能力的一种较好的赛前训练方法。对高原训练的起源及对人体呼吸、心血管、血液、骨骼肌、中枢神经等系统的影响进行了分析,为科学认识和实施高原训练提供参考。  相似文献   
20.
新世纪我国老年体育发展的困境与出路   总被引:1,自引:0,他引:1  
通过对新世纪我国老年体育发展所面临的主要困境与产生困境的社会背景进行分析和讨论,指出应加大政府宏观指导的力度、完善老年体育管理体制,注重老年体育消费市场的开发,加大老年体育专业指导人员的培养力度,拓宽筹集老年体育活动资金的渠道,丰富老年体育活动内容等。  相似文献   
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