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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
481

Ancient Egyptian linen : the role of natron and other salts in the preservation and conservation of archaeolgical textiles : a pilot study

Marsh-Letts, Glennda Susan, University of Western Sydney, School of Civic Engineering and Environment January 2002 (has links)
An understanding of the physical and chemical nature of archaeological textiles is an important prerequisite for their successful conservation treatment, display and storage. Ancient Egyptian linen textiles were examined through a combination of optical microscopy, environmental scanning electron microscopy (ESEM), ion chromatography (IC), and energy dispersive X-ray analysis (EDXA). These analytical techniques were used to distinguish between flax fibres, foreign matter present on and within flax fibres, and natron or other salts absorbed into the linen fibres in a form of partial mineralization. The use of ESEM enabled the observation and recording of the movement of salts, in real time, during cycles of hydration and dehydration. Few studies have been undertaken to date on the dynamics of salt crystallisation within organic archaeological materials, and none previous to this has been published showing the dynamics of salt crystallisation within archaeological textiles. Once the dynamics of salt crystallisation were viewed and recorded it became possible to investigate methods for the treatment of salt affected textiles through washing trials followed by alternative methods of drying. The release of salts from linen samples during washing in deionized water was monitored using IC and ESEM with EDXA, showing the pattern of salt removal and retention. The use of IC, ESEM and EDXA to monitor salt removal in textiles has not previously been reported. A conservation treatment for ancient Egyptian linen was developed, incorporating a long water washing to remove salts, soils and organic deposits, followed immediately by carefully controlled freeze drying. This was effective in preserving the integrity of the ancient linen. By combining archaeological, historical and chemical data, this pilot study of the effects of salts upon and within linen textiles has widened our understanding of the role played by salts in both the deterioration and the preservation of the textiles. / Doctor of Philosophy (PhD)
482

Development of a bio-preservation method for extended shelf-life cook-chill systems

Rodgers, Svetlana, University of Western Sydney, College of Science, Technology and Environment, School of Science, Food and Horticulture January 2003 (has links)
Extended shelf-life cook-chill meals can pose a potential risk of botulism if they are subjected to a temperature abuse. Spores of group II non-proteolytic Clostridium botulinum can survive the mild heat treatment typically given to these products and can grow at refrigeration temperatures. To circumvent this safety issue, existing preservation methods can either affect the sensory properties of these foods or damage their image. Therefore, additional natural preservation hurdles are needed. Thus, the aim of this study was to develop a novel bio-preservation method based on the principle of antibiosis between protective cultures (PCs) and C. botulinum. Consequently, the objectives were to select effective anti-botulinal cultures and study their inhibition pattern in microbiological media and foods, identify the conditions for effective inhibition and the nature of the antibiosis. This research demonstrates for the first time that the bacteriocinogenic protective cultures inoculated at high levels had an anti-botulinal effect in a range of commercial cook-chill products, which supported active growth of non-proteolytic C. botulinum. The protocol for commercial application of the protective cultures was developed. / Doctor of Philosophy (PhD)
483

The Influences on and Effectiveness of Environmemntal Policy-Making and Implementation in Japan: The Issue of Wildlife Preservation

Danaher, Mike, n/a January 2004 (has links)
This dissertation provides a descriptive-analytic study of the reasons and influences underlying Japan's less than progressive policy record on wildlife preservation, domestically and globally, since 1980. This research is important for a number of reasons, but mainly it helps us to test a number of theoretical models about: policy-making in Japan; Japanese environmental diplomacy; social movements; and corporatism. I hypothesise that apart from a common sense of purpose that binds the different policy actors together, Japan's poor record on wildlife preservation is a derivative of the way environmental NGOs have been marginalised and excluded from the policy process. This hypothesis links to Japan's public safety, and food and economic security concerns whereby these concerns tend to frame and guide policy-making on wildlife and nature issues. Using case study and participant observation methodologies to gather empirical evidence, this dissertation analyses both Japanese state behaviour towards global and domestic wildlife issues, and the changing relationships between the Japanese state, foreign pressure and environmental NGOs, in order to confirm or deny the hypothesis. The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) and the Ramsar Convention are the two environmental regimes which provide the context and issues for the analyses. The research concludes that there is convincing evidence to support the hypothesis. The research also reveals the positive, although subtle, sea changes which are occurring in Japanese environmental politics in the light of the continuing changes taking place in both Japan's broader political economy and in the international community.
484

Office Copying 1950-1970 : thermographic processes, their deterioration and preservation

Batterham, Ian, n/a January 2000 (has links)
This work looks at a range of copying processes used between 1950 and 1970 and which can be gathered under the heading 'Thermography'. Thermography is a broad term covering those processes which utilise heat to produce their image. The main aims of the work were: to examine how and when each process was used; to determine the chemistry of each process; to examine the permanence of existing copies produced using the various processes; and to look at possible ways of improving the preservation prospects of these copies. These aims were addressed through both primary and secondary research mechanisms. Research included examination of documentary source material, seeking out persons with first hand knowledge of the development of the processes, as well as analysis of extant copies from the various processes. Finally a series of preliminary experiments into the aging properties of the papers and the possibilities of preservation through the use of protective materials were carried out.
485

Internship in paper conservation at the National Library of Australia, Canberra, 1983-1984

Smith, Wendy, n/a January 1984 (has links)
This dissertation describes the work carried out by me in the Preservation Services Branch of the National Library of Australia during the period 1983 to early 1984. Conservation activities at the Library are organised in three broad categories, with the following goals: . preparation for exhibitions . ongoing full conservation of the Library collections, in a staged process . methods development and materials investigation. The internship program was devised to allow time to be spent in each of these three areas. The amount of time spent in each area roughly reflected the allocation of conservation staff resources to each section at that time. In the exhibitions program, objects were prepared for display at the National Gallery of Australia. These included watercolours and hand-coloured prints. Under the ongoing conservation program, a wide range of paper objects were treated. Objects from the Library's Special Collections are treated in order of priority determined by Librarian staff. Works treated included newspapers, both bound and unbound, movie posters, and magazines. Work in the third area involved both routine testing method's of conservation materials, involvement in a phase preservation project, and investigations into new methods of preventive conservation.
486

The identification of traditional binders used on Australian Aboriginal painted objects prior to 1970

Gatenby, Susannah Lija, n/a January 1996 (has links)
Many painted objects within ethnographic collections suffer from paint loss. In the past, assumptions have been made that this phenomenon was caused by a low binder concentration, although binder presence had not been investigated, confirmed or it's type identified. Simple laboratory methods which can detect the presence of binders on a painted object are outlined. They are based on tests developed for the medical industry and modified by the author for routine use in conservation. Methods presented outline procedures to identify three broad chemical groups of binders used in the manufacture of traditional Australian Aboriginal painted objects : 1. lipids (fats and/or oils) using Sudan Black B Bromination test and the Sigma GCI Triglyceride test; 2. proteins (egg and blood) using Sulphosalicylic Acid test, Sigma GCI Protein test and the GCI Heme test; 3. carbohydrates (honey and orchid juice) using the Sigma GCI Glucose test. Close comparison was found between the reported binders used on certain object types and those identified. Literature findings based on anthropological information on binders and pigments are summarised. They indicated that fat or oil binders have higher binder concentrations than originally expected. Rapid lipid binder deterioration has lead to their present matte appearance. Compared to protein and carbohydrate binders, used as a paint vehicle or facilitator and/or for symbolic representation (blood), where used on a range of ceremonial objects with no long term expectancy and therefore no requirement to adhere or bind the pigment. The concept of "effective" binder concentration as opposed to low binder concentration is discussed. Implications of these findings of binder presence are discussed and considerations for preservation and conservation treatments, which involve consolidation are outlined.
487

Sampling and management of garden symphylans (Scutigerella immaculata Newport) in western Oregon

Umble, Jon R. 25 October 2002 (has links)
Garden symphylans (Scutigerella immaculata Newport) are increasingly important pests of below-ground parts of over 100 crops in Oregon. The focus of our work was to improve S. immaculata management through 1) development of a bait sampling method, 2) examination of the susceptibility of selected crops to S. immaculata feeding in the field and laboratory and a reanalysis of previously published results, and 3) investigation of the suitability of selected crops and soil for the development of S. immaculata populations in the field and laboratory. Sample size requirements were developed for the bait and soil sampling methods. Estimating densities of 1 to 20 S. immaculata at fixed precision levels required 1.5 times more sample units for the baiting method than the soil method. Sampling recommendations for the baiting method performed well when validated by resampling a large independent data set. The bait sampling method provides an effective reliable alternative to the standard soil sampling method. In the laboratory, as S. immaculata densities increased, dry weight of spinach (Spinacia oleracea L.) and tomato (Lycopersicon esculentum L.) seedlings were significantly reduced from 85 to 89%, whereas corn (Zea mays L.) and potato (Solanum tuberosum L.) dry weight were not reduced. As S. immaculata densities increased in the field, the normalized difference vegetation index (NDVI) of squash (Cucurbita pepo L.) and broccoli (Brassica oleracea L.) crops sharply decreased, while the NDVI of corn and potato crops was only slightly reduced. In reanalysis of previously published data, the stand counts of crops seeded into S. immaculata infested soil appeared to increase as seed size increased. These findings will be used to help develop action thresholds and sample size requirements, and reduce S. immaculata damage. In the laboratory, S. immaculata population growth was significantly greater on spinach than on tomato, sweet corn, potato, or soil alone, and significantly lower on potato than on spinach, corn, tomato, or soil alone. In the field, greater S. immaculata population decreases were observed in potatoes than in sweet corn or clean fallow. These results provide strong evidence that crop rotation may significantly influence S. immaculata population levels. / Graduation date: 2003
488

Statistical design and analysis of sonic wave pressure treatment of wood

Nair, Hari U. 22 June 1994 (has links)
Literature reports have indicated that application of sonic pressure waves enhances the rate of impregnation of preservatives in wood. However, these studies have been limited and inconclusive. The technique or process is not in commercial use. In this study a laboratory scale treating cylinder connected to a mechanical sonic wave generator was used to measure the rate of impregnation of water in ponderosa pine at pressures of 0.28, 0.55 and 0.69 MPa and Douglas-fir at pressures of 0.55 and 0.69 MPa at a frequency of 30 Hz. Results were compared with those obtained at the same conditions of static hydraulic pressure. Statistical analysis showed that sonic treatments were at least as effective as, but not consistently superior to, hydraulic pressure treatments in the case of ponderosa pine. Statistical analysis of the results from Douglas-fir treatment showed that sonic treatment was superior than hydraulic treatment. / Graduation date: 1995
489

Deposition of chemicals in semi-porous solids using supercritical fluid carriers

Sahle-Demessie, Endalkachew 06 May 1994 (has links)
Graduation date: 1994
490

Effects of propionibacterial metabolites on spoilage and pathogenic bacteria in dairy products

Teo, Alex Yeow-Lim 28 October 1993 (has links)
Graduation date: 1994

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