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Desalination is a relatively new intervention in the field of conservation of architectural heritage. Especially the desalination of immovable objects, such as masonry structures, is still a trial-error practice. In the field, different desalination materials and methods are used, sometimes with unsatisfactory results. Better understanding of the desalination process is needed in order to support the conservator with clear guidelines for choosing a suitable desalination material and method. The research presented in this paper constitutes the first step towards the development of a modular system of poultices, which can be adapted, i.e. fine-tuned to different types of substrates. Starting point is to make use of advection, i.e. the transport of salt ions with water flow. This transport mechanism is faster than diffusion and the application on immovable objects is relatively easy. In order to optimize salt extraction, a poultice working by advection should have smaller pores than the substrate. Starting from this principle the pore sizes of different desalination materials (sand, cellulose, kaolin and bentonite) mixed in different proportions, have been measured. Interesting results were obtained, showing that the desalination materials commonly used in the field are often not the most suitable ones. On the basis of the results, recipes for poultices, adapted to a specific substrate, can be formulated. 相似文献
964.
Deterioration of Yungang Grottoes: Diagnosis and research 总被引:2,自引:0,他引:2
Yungang Grottoes, in Datong City of Shanxi Province, China, as the state-level key cultural relic preservation organ, have been subjected to severe degradation due to natural and human factors over the years. Since January 2010, site investigation and research on Yungang Grottoes, assisted by the Xi’an Relics Protection Center and Yungang Grottoes Cultural Research Institute, have been carried out in the laboratory of cultural relics conservation materials in Zhejiang University. Our investigation of the deterioration characteristics of these grottoes is presented here. The paper describes about 12 types of diseases in detail represented by dust deposit, salt crystallization and black crust. Relevant samples have been collected and analyzed by means of SEM, FT-IR, XRD and EDAX to study the potential hazard to the sandstones and conservation methods, which could be used to help guide remediation efforts directed at reducing the weathering problem. 相似文献
965.
Shi Yuewen 《中外文化交流(英文版)》2010,(1):32-33
On December 7, 2009, visiting Chinese Premier Wen Jiabao visited China Culture Center in Cairo, Eygpt and granted awards to nine Egyptians who had made outstanding contribution to China-Egypt cultural exchange, it was the first time that Chinese state leaders visited this cultural center since its inauguration 8 years ago. 相似文献
966.
J. Stanley Metcalfe 《Minerva》2010,48(1):5-33
It is commonplace to say that the modern economy is knowledge based but a moment’s reflection points to the vacuity of this notion. For all economies are knowledge based and could not be otherwise. The question is rather how is one kind of knowledge based economy to be distinguished from another? This essay proposes that the answer may lie in three directions: (1) in terms of the variety of knowledge that is engaged; (2) in terms of the processes by which the production of knowledge is organised, and its corollary the resources devoted to knowledge production and dissemination; and, (3) in terms of the purposes to which knowledge is put. In respect of each of these dimensions, the rise of the modern university as a custodian of knowledge in Western economy and society has been of central importance; but universities are not alone in this role, a wide range of other agencies, private firms, public research laboratories for instance play an important role in defining a knowledge economy and have done so increasingly since the turn of the nineteenth century—a first indication of the systemic dimensions of a modern knowledge economy. 相似文献
967.
José A. Montelongo Anita C. Hernández Roberta J. Herter 《Multicultural Perspectives》2014,16(3):170-177
English-Spanish cognates are an important subset of words in both the English and Spanish languages. Cognates are words that possess identical or nearly identical spellings and meanings in both languages as a result of being derived from Latin and Greek. Of major importance is the fact that many of the more than 20,000 cognates in English are academic vocabulary words, terms essential for comprehending school texts.?The Pura Belpré Children's Book Award has been given since 1996 to outstanding children's and young adult literature that represents, affirms, and celebrates the Latino cultural experience. The books are judged for their literary and artistic quality.?There are many English-Spanish cognates in each of the Pura Belpré picture books. The purpose of this article is to introduce the Pura Belpré Cognate Database, which lists all of the English-Spanish cognates for each of the children's picture books that have won the award or have been designated as honor books. Ideas for vocabulary, spelling, and morphology lessons or mini-lessons are also presented. 相似文献
968.
石坤 《吉林体育学院学报》2009,25(4):14-15
我国优秀运动员文化教育模式目前仍以运动技术学院为主体,根据不同的标准可以分为不同的类型,存在着竞技体育与非体育院校相结合的发展模式、竞技体育与体育院校相结合的发展模式、非体育院校办高水平运动队,创建“一条龙”的竞技体育体系发展模式等发展趋势。 相似文献
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