Electron beam evaporation of tungsten oxide films for gas sensors

Pure and Iron incorporated nanostructured Tungsten Oxide (WO3) thin films were investigated for gas sensing applications using noise spectroscopy. The WO3 sensor was able to detect lower concentrations (1 ppm-10 ppm) of NH3, CO, CH4 and Acetaldehyde gases at operating temperatures between 100 degrees celcius to 250 degrees celcius. The iron doped Tungsten Oxide sensor (WO3:Fe) showed some response to Acetaldehyde gas at relatively higher operating temperature (250 degrees celcius) and gas concentration of 10 ppm. The sensitivity of the WO3 sensor towards NH3, CH4 and Acetaldehyde at lower operating temperatures (50 degrees celcius - 100 degrees celcius) was significant when the sensor was photo-activated using blue-light emitting diode (Blue-LED). From the results, photo-activated WO3 thin film that operates at room temperature appeared to be a promising gas sensor. The overall results indicated that the WO3 sensor exhibited reproducibility for the detection of various gases and the WO3:Fe indicated some response towards Acetaldehyde gas.

Mechanical properties of thin sol-gel films

This thesis presents a study of the mechanical properties of thin films. The main aim was to determine the properties of sol-gel derived coatings. These films are used in a range of different applications and are known to be quite porous. Very little work has been carried out in this area and in order to study the mechanical properties of sol-gel films, some of the work was carried out on magnetron sputtered metal coatings in order to validate the techniques developed in this work. The main part of the work has concentrated on the development of various bending techniques to study the elastic modulus of the thin films, including both a small scale three-point bending, as well as a novel bi-axial bending technique based on a disk resting on three supporting balls. The bending techniques involve a load being applied to the sample being tested and the bending response to this force being recorded. These experiments were carried out using an ultra micro indentation system with very sensitive force and depth recording capabilities. By analysing the result of these forces and deflections using existing theories of elasticity, the elastic modulus may be determined. In addition to the bi-axial bending study, a finite element analysis of the stress distribution in a disk during bending was carried out. The results from the bi-axial bending tests of the magnetron sputtered films was confirmed by ultra micro indentation tests, giving information of the hardness and elastic modulus of the films. It was found that while the three point bending method gave acceptable results for uncoated steel substrates, it was very susceptible to slight deformations of the substrate. Improvements were made by more careful preparation of the substrates in order to avoid deformation. However the technique still failed to give reasonable results for coated specimens. In contrast, biaxial bending gave very reliable results even for very thin films and this technique was also found to be useful for determination of the properties of sol-gel coatings. In addition, an ultra micro indentation study of the hardness and elastic modulus of sol-gel films was conducted. This study included conventionally fired films as well as films ion implanted in a range of doses. The indentation tests showed that for implantation of H⁺ ions at doses exceeding 3x10¹⁶ ions/cm², the mechanical properties closely resembled those of films that were conventionally fired to 450°C.

Should cooking be a dietetic competency?

Aim:  There are issues surrounding the apparent decline and devaluing of cooking skills in the population, potential health impacts and the role of dietitians. The present paper aims to outline several arguments and raise questions on the relationship between cooking and dietetics.---------- Methods:  Evidence from dietetics and nutrition journals and other sources is used to develop positions for dietetics and its relationship to cooking and cooking skills. ---------- Results:  The historical relationship between dietetics and home economics has seen dietetics professionally distance itself by its scientific education on food and nutrition, rather than actual involvement with cooking. In pursuing this rational scientific approach there are concerns that dietitians have inadvertently supported the growth of the functional and convenience food market, particularly given the demise of home economics as a skill-based curricula in schools in several states. There is a need to consider what role cooking skills could have in dietetics training as a professional competency for practice, particularly for public health interventions. This is in the light of Commonwealth government funding that is legitimising cooking skill interventions as a policy response to obesity. There may be a role for dietitians to develop partnerships and train a new professional category or paraprofessionals and/or peer educators to deliver cooking skill interventions. ---------- Conclusion:  There is a need for research on dietitian's views and use of cooking skill interventions. This would help answer whether we should consider cooking and cooking skills as part of our professional practice and whether cooking should be a dietetic competency.

What's cooking for dietetics? A review of the literature

Aim: There has been no systematic research on the role of cooking skills for improving dietary intakes in Australia. Cooking skills are proposed to be declining and/or being devalued. If cooking skills have been devalued and declining, then what evidence is there for this decline and what impact might this have on dietary intakes? The aim of the present paper is to explore these assumptions with particular reference to Australia. The objectives of the present paper are to define the terms cooking and cooking skills, discuss evidence on levels of cooking skills in Australia and describe the evidence linking cooking skills to dietary intakes.---------- Methods: A review of the peer-reviewed literature using multiple databases from 1990 to September 2009.---------- Results: Cooking skills are complex and require a range of processes for people to develop efficiency or confidence in food preparation. There is little evidence on the level of cooking skills in the Australian population and how this relates to dietary intakes. The Australian Bureau of Statistic’s latest Time Use Survey and Household Expenditure Survey suggest that cooking is still a gendered activity and that the time devoted to cooking has changed little in the past 15 years, but there is an increasing use of foods prepared outside the home.---------- Conclusion: Further research is required to examine the prevalence of different types and levels of cooking skills in Australia as well as their potential effects on dietary intakes. Dietitians need evidence about the level of cooking skills people require for healthy dietary intakes.

Sound in the Aboriginal Australian Films of Rolf de Heer

Anna Hickey-Mody and Melissa Iocca invented a new name for the cinema-goer at "Bad Boy Bubby" (1993) when they wrote: "In de Heer's film, the viewer is primarily a listener, or aurator, and secondly a spectator" and I have argued the label 'aurator' can also be used for the person experiencing "Ten Canoes" (2006). This Aboriginal Australian Dreamtime fable features dialogue recorded entirely in the Ganalbingu language of the Indigenous people it stars, and is a prime example of what I would suggest can be labeled 'The Aboriginal Australian Films of Rolf de Heer'. "The Tracker" (2002) and "Dr. Plonk" (2007) have also included depictions of Aboriginal Australians and each of the trio utilizes Cat Hope's "innovative sound ideas" to present what I argue is an aural auteur's signature revealing a post-colonial Australian world-view that privileges the justice system and eco-spirituality of Aboriginal Australians.