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This paper presents a critical review of the reasons behind the initiation of this project to find a more sustainable, cost efficient, and safer form of chloride extraction that would result in stabilisation of archaeological copper and its alloys with tin and zinc. The imperative has become increasingly strident with cutbacks in funding for museum conservation facilities and with the reduction in staff, leaving less time for routine analyses of traditional immersive washing treatments that could take several years to effect. Owing to the faster oxidation and reduction kinetics of copper, compared with tin and zinc ions, the problems of uncontrolled corrosion of copper alloys in a chloride-rich environment have led to unacceptable levels of decay in heritage collection items. This study looked at the chloride extraction rates under subcritical conditions for both primary and secondary chloride-rich mineral species nantokite, clinoatacamite, and atacamite and determined the impact of changing the solution pH from 8 to 10, while also addressing the impact of temperature. The range of temperatures between 130 and 230°C was assessed at 50°C intervals at both levels of acidity of the leaching liquors. For the nantokite treatment, the formation of a cuprite patina which replaced the waxy-grey initial corrosion products was regarded as a bonus. The nature of the patina and changes in surface textures resulting from the treatment are critically reviewed and a series of recommendations for future work are included in the conclusion. [ABSTRACT FROM AUTHOR]

During the past 50 years the amount of chemistry applied to the preservation of all sorts of materials, from wood, to ceramics, glass and metallic objects has increased dramatically as materials conservation laboratories became established around the world. In Australia, the finding of a series of historic shipwrecks of ships from the Dutch Vereenigde Oostindische Compagnie (VOC) that operated in the 17th and 18th centuries catalysed activities in the Western Australian Museum. Since many of the forms of decay were peculiar to the well oxygenated, warm sub-tropical waters of Western Australia, new methods had to be developed to successfully stabilise these historic objects. Having developed research skills in producing new methods to stabilise shipwreck materials, the museum work program was extended to include Aboriginal rock art sites and historical objects of value to the WA community. Part of the success of the WA Museum in managing these and related issues is summarised in the three case histories highlighted in this article which reflect the diversity of cultural experiences found in this state. Dr Ian D MacLeod is an electrochemist who has pioneered in-situ conservation and corrosion studies on historic shipwrecks off the Western Australian coast. In this article, he provides an overview of his fascinating work in preserving some of Australia's rich cultural heritage through applied chemistry.

Compares two models used for text storage and retrieval systems, the text model and the relational model. Characteristics of documents and document collections are discussed, trends in document processing are described, and future directions of document management systems are suggested. (20 references) (LRW)

Describes a conceptual model for bibliographic data called Maestro (Management Environment for Structured Text Retrieval and Organization) that is being developed both to support structured documents in databases, and to provide a query language to link information contained in these structures. Traditional text retrieval systems are discussed, and implementation strategies are described. (22 references) (LRW)