The Influence of Hygroscopic Materials on the Fluctuation of Relative Humidity in Museums Located in Historical Buildings

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.     

法律行为的原因浅析

法律行为的原因是法律行为所具有的法律效果之外的权利义务状态,是当事人从事财产给付行为所要达到的交易目的,不能以法律行为本身的法律效果来说明法律行为的原因。法律行为的原因与无因行为的“因”是同一概念,都是行为人所要达到的交易目的。标的与内容是同一概念,标的、合意与原因是有区别的。     

略论海事诉讼时效协议延长的法律效力

允许当事人协议延长诉讼时效是海商法特有的一项制度。自本世纪六十年代起,与国际贸易惯例的国际化相适应,这一制度历经了一个成文化的过程,在这一过程中,它同时具有国际条约、国际惯例和国内法等三种法律表现形式,从而产生了确认其法律效力的困难。本文以为,在有法律明文规定的国家,它的法律效率是当然的;在接受国际惯例之拘束力的国家,它同样可以产生法律效力。我国是明确规定可以适用国际惯例的,因而这一制度在我国也可以得到适用。     

解读名词数念的似是而非现象

英语名词单复数念变化,常常是初学者深感困扰、迷惑不解的问题,一定程度上影响其阅读和理解。本文从教学实践出发,较为详尽地总结了电大教材中常见的英语名词单复数念变化的实例,并加以条理化,旨在帮助电大学生系统地学习名词单复数变化的规律性,从而提高其阅读能力和速度。     

数字资源整合检索协议研究

简要地论述了数字资源整合检索的必要性、模式、以及联接方式和联接方法，并详细地介绍了三种数字资源整合检索的协议：Z39．50、OAI、OpenuRL。     

一类非线性系统的有限时间镇定问题

讨论了一类非线性系统的有限时间镇定问题.通过利用"加幂积分器"的方法构造出了一个部分状态反馈控制律,解决了这类非线性系统的有限时间镇定问题.     

The Decline of the ‘Elite’ Sport Officials and the Dissolution of the Israeli Sport Association

This historical study will examine the rise of a hegemonic group of sports officials in Israel during the period between 1948 and 1996. The formation of this group is a unique phenomenon of the Israeli sport society. The main argument of the study is that officials of rival sport centres, ‘Hapoel’ and ‘Maccabi’, founded a joint elite group as a side effect of the ‘fifty-fifty’ agreement, signed in 1951. The agreement stated that the Israeli Sport Association, the National Olympic Committee and the Israeli Football Association would be mutually led by officials of both organizations. The members of this elite group, who enjoyed access to economic resources and other benefits, adopted a hedonistic lifestyle, in contrast to the social ethos of Israeli society in the first and second decades of the State. Three events dismantled the group in the middle of the 1990s. The first one was the establishment of the Elite Sport Department in 1984. The second was the establishment of independent Federations by Yadin Machnes. The third was the Maliniak Commission Report. These three events led to the collapse of the Israeli Sport Association in 1996 and to the fall of the Israeli hegemonic group.     

短文改错技巧口诀

短文改错对于多数学生来说,是考试中比较困难的一部分,因为短文改错是从语法、结构、词汇等方面来全面考核学生,若你掌握了下列一则口诀,你会觉得轻松多了.     

高等教育大众化背景下的大学生稳定工作

高等教育从精英阶段向大众化阶段的转变，既为高等教育的发展提供了广阔的前景，也产生了一些影响大学生稳定的新因素，如教育资源的相对短缺，学习费用上升，毕业就业困难，特困生增多。当前，要做好大学生稳定工作，必须有针对性地加强形势政策教育，必须建立大学生的舆情调查、分析、反馈体系，必须构建强有力的就业指导，服务体系和帮困体系。     

中国文化背景下对丧失的理解与处理

丧失是人类生命历程中最为深重的情感,在不同的文化背景下,人们对丧失与哀伤有着不同的言说,每个个体对丧失的理解不同,就意味着对生命意义的理解不同,也意味着面对丧失与哀伤的方式不同。本文通过对几个有关丧失的个案,讨论了如何在中国文化容器下安放哀伤与哀悼,促进当事人的稳定化。