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   

„Karrieren“ von Mädchen und Frauen im Sport     

S. Keck 《Sportwissenschaft》1995,25(2):206-210

  相似文献   

Journal notes     

Beatty WK 《Bulletin of the Medical Library Association》1989,77(1):101-103

  相似文献   

Irwin h. Pizer, twentieth editor of the bulletin     

Crawford S 《Bulletin of the Medical Library Association》1989,77(1):77-78

  相似文献   

Acquiring unpublished population documents in Africa: a personal experience     

Kwafo-akoto KO 《Aslib proceedings》1988,40(4):105-110

Acquiring both published and unpublished documents produced in Africa is, generally, a difficult task due to the existing poor state of bibliographic control and the publishing industry. It is even more difficult to obtain unpublished documents in a specialized area of study such as demography--a diffuse area which cuts across several disciplines. This paper discusses the problems encountered on acquisition trips to some African countries to acquire unpublished population material. To help solve the problems, the Population Association of Africa must persuade its members to send copies of their publications to population libraries and documentation centers in their individual countries for dissemination to the other users in Africa. The various organizations and institutions in Africa engaged in the teaching and research of population studies should have an agreement to exchange copies of their theses. The Economic Commission for Africa (ECA) and the Organization of African Unity (OAU) should make representations to the various African member countries on the need to disseminate the results of vital censuses and surveys conducted. Finally, the Population Information Network for Africa (POPIN-AFRICA) with its coordinating unit at the population division of ECA should ensure that all the nodes of the network have the financial and other resources to be able to acquire the relevant documents needed for their operations.  相似文献   

Introducing computer literacy skills for physicians     

Collins B  Linton A  Merril J  Pomerantz K  Winthrop S 《Medical reference services quarterly》1992,11(4):1-9

Computers are integral to medical practice, education, and research. While medical students learn computer skills during their training, many practicing physicians do not have the same computer experience. To familiarize this group with the exciting developments in medical informatics, the Himmelfarb Health Sciences Library and Department of Computer Medicine at the George Washington University Medical Center organized a workshop "Introducing Your Office Computer!" for attending physicians. The workshop featured a short lecture/video presentation on computer applications in medicine followed by a "computer fair" of five computer applications. Eleven physicians attended the workshop. Feedback was very positive; many called later to request more detailed instructions on using the programs demonstrated. It was a valuable experience for the staff, and new bridges were built between departments and clients.  相似文献   

The standard issues     

Wallace S 《Inform (Silver Spring, Md.)》1992,6(1):14-6, 18-9

  相似文献   

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   

Journal notes     

Beatty WK 《Bulletin of the Medical Library Association》1986,74(3):284-287

  相似文献   

Introduction     

Mayfield K 《Bulletin of the Medical Library Association》1986,74(2):139-141

  相似文献