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People, mussels, and country: using traditional ecological knowledge and western scientific techniques to Investigate human-mussel-environment relationships during the Late Quaternary on Ngintait and Latji Latji Country, South East Australia
(Australian Archaeological Association, 2024-12-03) Stringer, C; Prendergast, A; Garvey, J; May, JH; First People of the Millewa Mallee Aboriginal Corporation; Wong, HKY; Levchenko, VA; Drysdale R,
Freshwater mussel shells are commonly recorded in Aboriginal archaeological sites in the Central Murray River Basin (CMRB), on Ngintait, Latji Latji, and First People of the Millewa Mallee Country. Middens containing freshwater mussel shell are found in great number along the banks of the Millewa (Murray River) and these shells have been used to determine that CMRB has been inhabited for at least 29,000 years. Yet, so far, it has been difficult to ascertain the cultural and economic significance of this resource to the region’s inhabitants. This research aims to gain a more holistic understanding of human-mussel-environment relationships in the CMRB through the incorporation of evidence from a variety of knowledge systems and different techniques applied to two shell middens in the region: Knowledge (TEK) gained through collaboration and interviews with the Ngintait, Latji Latji, and First People of the Millewa Mallee community is combined with several Western scientific techniques. The application of sclerochronology unlocks the high-resolution climate record stored within the freshwater mussel shell itself, allowing for the seasonal climate at the time that the mussels were collected to be determined. These estimations of time-of-year of collection can provide insight into resource habits and movement of Ngintait and Latji Latji peoples across Country. Nutritional analysis of modern specimens collected throughout the year can also help us to understand whether season of collection may be linked to changes in the nutritional value of the mussels themselves. Radiocarbon dating allows for the narratives unearthed to be placed in a larger chronological context. A more holistic understanding of human-mussel-environment relationships will allow us to best interpret the cultural and economic importance of freshwater mussels in the CMRB and understand how this relationship may have changed through time. © The Authors
Hot-pressing behaviour of Synroc containing sodium-bearing nuclear wastes
(Trans Tech Publications, 1991-08) Stewart. MWA; Buykx, WJ
The hot-pressing behaviour of SYNROC powders prepared from "alkoxide-route" precursors was studied using isothermal and dilatometrical techniques. The effects of variations in the type (with and without Na) and loading of the simulated high level radioactive waste (HLW) were examined. The calculated optimum hot-pressing temperature drops by about 10 - 30°C for each 7 MPa increase in pressure and 10 % increase in the HLW loading. The presence of Na in the HLW lowers the calculated optimum hot-pressing temperature at 21 MPa by 60 - 100°C, depending upon the waste loading. At higher waste loadings, densification of Na-bearing SYNROC is inhibited by pore formation within the pellet. There is some evidence that the densification mechanisms of Na-bearing and non-Na-bearing SYNROC are different.
Energy dispersive x-ray spectroscopy in the transmission electron microscope – precision and accuracy
(ScienceOpen, 2025-02-02) Aughterson, RD; Zaluzec, NJ; Lumpkin, GR
The relative ease of using the EDS technique to analyse the elemental composition of specimens has meant that this characterisation technique is almost ubiquitous with electron microscopy. However, the depth of analysis widely ranges from qualitative to “semi-quantitative” through to quantitative. The approach to data collection and analysis will depend on the researchers’ final goal; are they looking to detect the presence or otherwise of a particular element (qualitative EDS), do they need to confirm a particular mineral phase has been formed (semi-quantitative EDS), is there an exact stoichiometry that has been targeted (quantitative EDS). It is possible to achieve a precision of measurement better than 1 % without too much work. This precision is dependent on the x-ray counts collected with high counts being readily attainable for many elements even when nano-metre thin TEM specimens are used. How “quantitative” this data is depends on the x-ray counts, the number of grains sampled, along with the relativeness of the standards to the measurement of the unknown. Another limiting factor for EDS quantitative analysis in the TEM is x-ray absorption. This is a most significant influence to x-rays of ~ 1 keV or less making analysis of elements like oxygen difficult. It is however still possible to achieve quantification of the lighter elements with a little extra work. With a focus on using k-factors for calibration the advantages / disadvantages of this technique will be discussed along with a few easy to follow tips on how best to quantify EDS data in the TEM. The precision of EDS measurements will be discussed with examples of how thickness, density and crystal structure may all create varying levels of deviations within the data. Further to this, examples of how crystal structure related channelling can affect the x-ray signals, and a novel approach, amorphisation can be used to rectify this potential issue. © 2025 The Authors.
Disposal of wastes from uranium conversion and enrichment processes
(Australian Institute of Nuclear Science and Engineering, 1981-11-12) Costello, JM
The majority of Australian uranium exports will be used to generate nuclear power in Light Water Reactors. Crude uranium ore concentrates will be refined and converted into pure natural uranium hexafluoride. This will be enriched in the uranium-235 isotope and used to manufacture enriched uranium dioxide fuel. The production of enriched uranium hexafluoride for export is a topical Australian interest in the nuclear fuel cycle. These upgrading operations give rise to solid, liquid and gaseous wastes for disposal. The wastes include chemical effluents containing small quantities of naturally occurring radioactivity, and non-radiological effluents including used cooling water stream. This paper reviews the general principles and objectives in radioactive waste management, and shows how these are applied in options for management and disposal of wastes from uranium upgrading operations. Some estimates of radiological dose commitments and health effects from LWR nuclear power and its fuel cycle have been made for US conditions. Doses from the upgrading processes of hexafluoride manufacture and enrichment were about O. 007% of the total body dose received by the US population from natural radiation background sources.
Measuring residual stress in active materials
(Australian Nuclear Science and Technology Organisation, 2012-01-10) Law, M
Nuclear technologies such as fission and fusion systems, and associated waste storage and disposal rely on advanced structural materials. ANSTO is a member of the IAEA Co-operative Research Program on “Development, Characterization and Testing of Materials of Relevance to Nuclear Energy Sector Using Neutron Beams”. A significant part of this program will be the characterisation of active materials, particularly assessing the evolution of texture and residual stress with service (typically irradiation and sometimes high stress and/or temperature). Problems to be addressed for the analysis of active samples include transport and sample preparation, mounting the sample on the instrument, and measurement (including any effects of background). Some examples of measurement of active samples will be given.

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