Environmentally-induced stone decay: the cumulative effects of crystallization–hydration cycles on a Lincolnshire oopelsparite limestone     

Belinda J. Colston  David S. Watt  Helen L. Munro   《Journal of Cultural Heritage》2001,2(4)

An investigation has been undertaken at St Andrew’s church, Walpole St Andrew, Norfolk, to establish the underlying causes of the observed stone decay to the upper parts of the six stone piers. The stone decay was first recorded in the early 1930s. The salt-contaminated masonry within the church has been shown to undergo severe salt decay during the summer, with little damage occurring over the winter months. The south aisle piers have been shown to decay 2.5 times faster than the north aisle piers. Although crystallization–hydration cycles have been identified, the rate of decay is at its greatest when the cycling is relatively infrequent. This was not the expected trend. Furthermore, it has been shown that during extended periods where the ambient relative humidity is less than 75%, the rate of decay reaches a maximum. It is the length of this ‘drying’ period that apparently has the greatest influence on the rate of decay and could explain the significant difference in the rate of decay between the south and north aisle piers. The results have serious implications for passive conservation, where it is often recommended to lower the ambient relative humidity to well below the equilibrium relative humidity of the salt contaminant, to avoid crystallization–hydration cycles. Since, at the time of building, the church was situated on the coast, it is possible that the sodium chloride contamination occurred during the building process (1440–1520), particularly since the area was prone to sea-flooding at this time. Alternatively, the salt could have been applied as a treatment during the general restoration of 1897. Whatever the source of the salt, it seems likely that the ambient environment was changed by the insertion of a sealed floor in 1897, which could account for the onset of the salt decay.  相似文献   

Response to Kronick     

L Heshusius 《Journal of learning disabilities》1990,23(8):458-459

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Cycles, a crystal ball, and the telecommunications- act of 1996—Been there, done that     

Robert E. Dugan  Jennifer L. Souza  Timothy V. Cash 《The Journal of Academic Librarianship》1996,22(6):457-461

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ADONIS—latest developments and its role in the changing publisher/library relationship     

HENK C. J. COMPIER  ROBERT M. CAMPBELL  B. V. ADONIS 《Health information and libraries journal》1992,9(1):3-13

Exporting the American (information) revolution: the international impact of the National Library of Medicine     

E V Smith  F S Janson 《Bulletin of the Medical Library Association》1986,74(4):339-343

The National Library of Medicine has had an enormous impact on health information services all over the world. Although NLM is primarily a national institution, it has become an important international resource by responding to requests from the international community. NLM has been influential in three major ways. First, NLM has provided a model for other national and regional health information services. Second, it has been a catalyst, in that MEDLARS and other services it provides formed the nucleus of many regional networks. NLM helped such networks get started by giving advice on how to set up services and build collections and by "training the trainers" on the MEDLARS system. Third, NLM has supported national and regional operations by providing the additional training and materials needed for day-to-day service.  相似文献   

Measures of excellence: the search for the gold standard.     

V H Holtz 《Journal of the Medical Library Association》1986,74(4):305-314

Questions concerning some of the values we hold as librarians and the goals, standards, and other evaluation tools we derive from them are discussed in the context of the history of our profession and the present period of rapid change. The concepts of stable and changing paradigms and of "scientific communities" provide the foundation for consideration of how a changing conceptual framework can affect values and their application in the evaluation process. One of many possible scenarios for the future is briefly outlined to demonstrate how some traditional values may fare.  相似文献   

The Buffalo Medical Journal: 1845-1919     

L Sentz 《Bulletin of the Medical Library Association》1985,73(3):278-282

Fielding H. Garrison's paper "The medical periodical and the scientific society" cited the Buffalo Medical Journal in the company of eminent periodicals published in Berlin, Boston, and Edinburgh. This article provides an overview of the Journal and places it in context of 19th-century medical journalism. The Journal is assessed in terms of original scientific contributions and as a source of social and local history.  相似文献   

The statistician's role in society: The institutional establishment of statistics in France     

Lécuyer BP 《Minerva》1987,25(1-2):35-55

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Summary report of a study of academic medical library statistics     

V M Pings  E E Olson  R H Orr 《Bulletin of the Medical Library Association》1969,57(3):233-238

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The MEDLARS regional center at UCLA: a progress report     

L Darling 《Bulletin of the Medical Library Association》1966,54(4):311-315

This paper supplements information given in earlier papers on the UCLA MEDLARS Search Station. Four major machine problem areas in the operation of a decentralized station are identified: adjustments required to run a large information retrieval type program in an academic computing facility serving many users; handicap in running time for COBOL programs; advent of the third generation of computers with attendant preparation; and need for constant current communication among all members of a decentralized network system. Statistics are given for the initial operating period, January-May 1966: 119 search requests received, 109 formulated, and 60 fully processed. Parallel searches with other MEDLARS installations, comparisons of MEDLARS and manual Index Medicus searches, and other search activities are reported.  相似文献