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)

Thesis (Ph.D.) -- University of Western Sydney, 2002. / A thesis submitted in fulfilment of the requirements for the degree of Doctor of Philosophy, 2002. Bibliography : leaves 287-331.

Diploma thesis studies historical bonding agents on the base of geopolymers. The aim of the thesis is to find a proper material composition, especially made of natural clay materials (kaolinite, bentinite) and their modifications (metakaoline). These bonding agents have to have a suitable type of an activator that guarantees good bonding properties. Therefore testing of various kinds of alkaline activating ingredients on the same mineral composition was done. Except of usual hydroxides and a water glass, ancient natrons (mixtures of alkaline carbonate with addition of appropriate chlorides) and a lime mash were used as the activators. From the above mentioned mixtures, series of samples (columns 20 x 20 x 100 mm) stored at the laboratory temperature were prepared. In the prepared mashes, their workableness and moulding were investigated. In the developed samples, their surface appearance was observed together with a number of efflorescence and its types. An indivisible part of the research was formed by determination of mechanical properties of the experimental columns such as a compressive strength and a tensile strength in bending. Furthermore, phase composition of the samples and its changes with a temperature increase were investigated. For these tests, XRD and TG – DTA methods were used. A multi-seat isoperbolic calorimeter was used to study hydratation that was also the important part of the general evaluation of designed mixtures.

The East African Rift System diverges in the Lake Natron Basin of Northern Tanzania and is a major zone of continental extension and crustal thinning with resulting in active tectonics and volcanism. The discovery of Acheulean technology in Olduvai Gorge and Peninj as well as the presence of significant volcanic centers, has made in the region subject to studies in various disciplines. However, lack of precise radiometric age constraints due to the complex geology of the region is a major drawback. The basin is bordered on the western side by an escarpment that contains thick sequences of volcanic (nephelinites, basanites, hawaiites, alkali basalts), volcaniclastic and lacustrine strata that predates 1.2 Ma. This thesis is based on 41 rock samples that were collected from two geological sections, the Endukai Kete (EK) and Waterfall (WF) sections and aims to establish a preliminary geomagnetic polarity time scale (GPTS) for the Natron Escarpment, together with establishing possible flow directions of the volcanic lavas within these sections. Nephelinites of EK section have an inferred NW-SE direction of flow, based on study of anisotropy of magnetic susceptibility. They record a normal polarity that most likely correspond to the Cobb Mountain Event (CMT; 1.187-1.208 Ma), although there is an 80-ka discrepancy between the CMT event and the dated lavas. The most probable source is the Mosonik that erupted nephelinitic lavas 1.28 Ma ago. The palagonitic tuff layer below the nephelinites displays reverse polarity and a NE-SW direction of flow. Due to the absence of approximately 200 m strata within the basanite series of the section, regional lithological correlation is used to constrain the GPTS pattern. Hajaro Beds of the Peninj Group to the north of the escarpment, postdates the Olduvai Event (1.71 to 1.86 Ma) and lacustrine strata of the escarpment for EK and WF sections are deposited over the same unconformity and share depositional similarities. Therefore, the lacustrine strata are correlative to Hajaro beds and the normal event observed within the basanite series of both sections is attributed to the Réunion Event (2.116 – 2.137 Ma). The establishment of a preliminary magnetostratigraphic sequence presented in this thesis demonstrate that the rift escarpment in northern Tanzania is suitable for paleomagnetic dating. Future studies should be conducted to establish a more detailed and constrained magnetostratigraphic section, which will be of great use in this part of the African Rift where radiometric dating has been challenging.