31 resultados para CASEY STATION

em Deakin Research Online - Australia


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During the 2009/2010 summer, a comprehensive environmental impact assessment (EIA) of the wastewater discharge at Davis Station, East Antarctica was completed. As part of this, histological alteration of gill and liver tissue in Antarctic Rock-cod (Trematomus bernacchii) from four sites along a spatial gradient from the wastewater outfall were assessed. All fish within 800 m of the outfall exhibited significant histological changes in both tissues. Common pathologies observed in fish closest to the outfall include proliferation of epithelial cells with associated secondary lamellar fusion in the gills and multifocal granulomata with inflammation and necrosis as well as cysts in the liver. Fish from sites >800 m from the outfall also exhibited alterations but to a lesser degree, with prevalence and severity decreasing with increasing distance from the outfall. This study highlights the value of histopathological investigations as part of EIAs and provides the first evidence of sub-lethal alteration associated with wastewater discharge in East Antarctica.

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This study investigated the role of a permanently manned Australian Antarctic research station (Casey Station) as a source of contemporary persistent organic pollutants (POPs) to the local environment. Polybrominated diphenyl ethers (PBDEs) and poly- and perfluoroalkylated substances (PFASs) were found in indoor dust and treated wastewater effluent of the station. PBDE (e.g., BDE-209 26-820 ng g(-1) dry weight (dw)) and PFAS levels (e.g., PFOS 3.8-2400 ng g(-1) (dw)) in dust were consistent with those previously reported in homes and offices from Australia, reflecting consumer products and materials of the host nation. The levels of PBDEs and PFASs in wastewater (e.g., BDE-209 71-400 ng L(-1)) were in the upper range of concentrations reported for secondary treatment plants in other parts of the world. The chemical profiles of some PFAS samples were, however, different from domestic profiles. Dispersal of chemicals into the immediate marine and terrestrial environments was investigated by analysis of abiotic and biotic matrices. Analytes showed decreasing concentrations with increasing distance from the station. This study provides the first evidence of PFAS input to Polar regions via local research stations and demonstrates the introduction of POPs recently listed under the Stockholm Convention into the Antarctic environment through local human activities.

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An overview of the design and performance of geosynthetics in composite barrier systems for biopiles used to remediate hydrocarbon-contaminated soil at Casey Station, Antarctica, is presented. Seven instrumented biopiles were constructed over three field seasons. To minimize the risk of hydrocarbon migration to groundwater, composite barrier systems were used (each using different combinations of geosynthetic clay liners (GCLs), high density polyethylene (HDPE) geomembranes (GMB), and geotextiles (GTXs)). One biopile used a co-extruded geomembrane (HDPE with an ethylene vinyl alcohol (EVOH) core). The liner system was subject to a combination of coupled phenomena that could interact and affect the GMB-GCL composite barrier performance. The exposure conditions involved potential freeze-thaw cycling, hydration-desiccation cycles, cation exchange, direct and diffusive exposure to hydrocarbons. The effect of these phenomena was investigated by monitoring GCL and GMB sacrificial coupons. GCL coupons were placed between the main GCL component and the main geomembrane component of the composite liner and GMB coupons placed between the main GMB sheet and the GTX protection layer. Coupons were exhumed from the biopiles each year. The exhumed GCL field moisture content values ranged from 162% to 22%. After three (3) years in the field, GCL coupons that had undergone at least one hydration/desiccation cycle showed no significant change in swell index values or fluid loss values. The measured hydraulic conductivity of exhumed GCL coupons from Biopiles 1 and 2 (3 × 10-11 m s-1) was within the expected range and not significantly different from the values for virgin GCL. GMB coupons exhumed after three years from Biopiles 1 and 2 showed no significant change in oxidative induction time (OIT), melt flow index or tensile properties. Diffusion tests were performed as an index test for establishing the performance of the GMBs as a diffusive barrier to hydrocarbons, with permeation parameters for BTEX contaminants ranging from P g = 0.9-9.2 × 10-13 m2 s-1 for the exhumed GMB (with values depending on the contaminant and GMB). These values were similar to the parameters obtained for virgin GMBs and there was no significant change with field exposure, with GMBs appearing to be performing well.

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Richard Casey was involved in shaping Australian foreign policy for over four decades. Casey's attitudes, ideas, policies and actions towards the rest of the world are therefore an important part of a Liberal tradition in Australian foreign policy. To examine Casey's place in the Liberal tradition this article explores Casey's positions on the great international issues of two periods: the 1930s and the 1950s. The conclusion of the article is that three key ideas shaped Casey's foreign policy, and therefore also lie at the centre of the Liberal tradition; firstly, a strong attachment to the idea of the English speaking alliance; secondly, a realist perspective on international affairs; and, thirdly, a consistent strand of anti-communism.

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In this study, Australian brown coal fly ash particles have been collected from power station and analysed by scanning electron microscopy to obtain morphological information and elemental composition of individual particles. The most common particles found to be the irregular shape particle aggregates. Other shapes include ball shape with smooth surface and with some attachments; and crystal shape fine particles. The X-ray spectra of each fly ash particle revealed five groups of elemental composition, they are Si-rich particles; Ca-rich particles; Fe-rich particles; particles with Mg-Ca Matrix and particles with Si-Ca matrix. A particle sire distribution analysis has been conducted using particle size analyser and found to have a mean particle size of 21fim. The sample then was separated into fine and coarse fractions using aerodynamic classifier, and the elemental composition of both fractions were determined by ICP-AES. Borate fusion and acid dissolution method was used for sample preparation. It is found that some environmental sensitive elements such as Zn, Pb, Ni, K and Cu are enriched in fine fly ash particles. Ca has much higher contents in fine particles as well. Si and Mg have higher concentrations in coarse particles.

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Artificial neural network (NN) is an alternative way (to conventional physical or chemical based modeling technique) to solve complex ill-defined problems. Neural networks trained from historical data are able to handle nonlinear problems and to find the relationship between input data and output data when there is no obvious one between them. Neural Networks has been successfully used in control, robotic, pattern recognition, forecasting areas. This paper presents an application of neural networks in finding some key factors eg. heat loss factor in power station modeling process. In the conventional modeling of power station, these factors such as heat loss are normally determined by experience or “rule of thumb”. To get an accurate estimation of these factors special experiment needs to be carried out and is a very time consuming process. In this paper the neural networks (technique) is used to assist this difficult conventional modeling process. The historical data from a real running brown coal power station in Victoria has been used to train the neural network model and the outcomes of the trained NN model will be used to determine the factors in the conventional energy modeling of the power stations that is under the development as a part of an on-going ARC Linkage project aiming to detail modeling the internal energy flows in the power station.

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The City of Casey is the fourth fastest growing region in Australia. Thus far its success is population driven. This paper reviews the recent trend in regional development policies in Australia with particular reference to Casey. A new model based on the Regional Innovation System framework for the analysis of development in the region is constructed. Questions are raised about whether this region can have economically sustainable and innovation driven development in the future

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It is known that the consumption of fast food is associated with obesity (Binkley 2000). Relative ease of access to fast foods compared with healthy foods may contribute to the increasing prevalence of obesity. The aim of this study was to determine and compare the access by car to fast foods and a healthy diet. The study was located in the City of Casey, a municipality in South East Melbourne with a population of 220,000. We have previously shown that ease of access to a large chain supermarket ensures access to a basket of healthy foods adequate to meet the nutritional needs of a family of 6 (Burns 2004). The City of Casey council provided location details for major fast food outlets and supermarkets. Fast food was defined as food sourced from an outlet without table service. We included only those major fast food chain outlets which had more than 10 franchises within Australia. We included the 3 major supermarket chains that account for 87% total food retailing in Victoria. Geographic details from the City of Casey were used to map the location of these outlets. Then using these locations and road network a basic cost distance model was created for either the supermarket chains or fast food chains outlets. The cost unit is (time), it was to calculate by giving the roads in the network an average travel speed depending in the type of road (minor, major or highway) and then calculating how long it would take to reach the closest outlet. Access to supermarket and fast food outlets were determined relative to population density.
Our results indicate that in the City of Casey most (> 80%) people live within an 8-10 minute car journey of a major supermarket and a fast food outlet. Fifty percent of the fast food outlets are co-located with a supermarket. We conclude that access to both healthy food and fast food in the City of Casey is good if you own a car. The increasing demand for fast food is easily met in this municipality. Obesity prevention strategies in Casey should concentrate on the food choices available at fast food outlets and town planning to ensure a mix of food outlets to maximize the likelihood of healthy food choices.

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The research aims to provide improvements to remediation practices for land contaminated by service station activities in the period 1988-2004 by assessing previous methods of remediation. Thirty-four such Queensland sites were examined. The resultes will be useful to government, developers, land holders, consultants and the community.