Process for the production of ultrafine plate-like alumina particles

A process for producing plate-like alumina particles with a high aspect ratio is described. Nano-sized particles of an aluminium precursor compound, optionally formed by milling, are mixed with a sufficient volume fraction of a diluent and heat treated to form substantially discrete plate-like alpha alumina particles dispersed in the diluent. A mineraliser may be added to lower the effective melting point of the system. Substantially discrete plate-like particles may be formed without agitation when the heat treatment is conducted below the melting point of the diluent.

Process for the production of ultrafine powders

A process for the production of ultrafine powders consisting of individual particles with sizes in the range of 1 nm to 200 nm, which is based on the mechanical milling of two or more non-reacting powders. The process includes subjecting a suitable precursor metal compound and a non-reactant diluent phased to mechanical milling which through the process of mechanical activation reduces the microstructure of the mixture of the form of nano-sized grains of the metal compound uniformly dispersed in the diluent phase. Heat treating the milled powder converts the nano-sized grains of the precursor metal compound into a desired metal oxide phase. Alternatively, the precursor metal compound may itself be an oxide phase which has the requisite milling properties to form nanograins when milled with a diluent. An ultrafine powder is produced by removing the diluent phase such that nano-sized grains of the desired metal oxide phase are left behind. The process facilitates a significant degree of control over the particle size and size distribution of the particles in the ultrafine powder by controlling the parameters of mechanical activation and heat treatment.

The effects of speech production and vocabulary training on different components of spoken language performance

A group of 21 hard-of-hearing and deaf children attending primary school were trained by their teachers on the production of selected consonants and on the meanings of selected words. Speech production, vocabulary knowledge, reading aloud, and speech perception measures were obtained before and after each type of training. The speech production training produced a small but significant improvement in the percentage of consonants correctly produced in words. The vocabulary training improved knowledge of word meanings substantially. Performance on speech perception and reading aloud were significantly improved by both types of training. These results were in accord with the predictions of a mathematical model put forward to describe the relationships between speech perception, speech production, and language measures in children (Paatsch, Blamey, Sarant, Martin, & Bow, 2004). These training data demonstrate that the relationships between the measures are causal. In other words, improvements in speech production and vocabulary performance produced by training will carry over into predictable improvements in speech perception and reading scores. Furthermore, the model will help educators identify the most effective methods of improving receptive and expressive spoken language for individual children who are deaf or hard of hearing.

Separating the contributions of hearing, lexical knowledge and speech production to speech perception scores in children with hearing impairments.

Open-set word and sentence speech-perception test scores are commonly used as a measure of hearing abilities in children and adults using cochlear implants and/or hearing aids. These tests are usually presented auditorily with a verbal response. In the case of children, scores are typically lower and more variable than for adults with hearing impairments using similar devices. It is difficult to interpret children's speech-perception scores without considering the effects of lexical knowledge and speech-production abilities on their responses. This study postulated a simple mathematical model to describe the effects of hearing, lexical knowledge, and speech production on the perception test scores for monosyllabic words by children with impaired hearing. Thirty-three primary-school children with impaired hearing, fitted with hearing aids and/or cochlear implants, were evaluated using speech-perception, reading-aloud, speech-production, and language measures. These various measures were incorporated in the mathematical model, which revealed that performance in an open-set word-perception test in the auditory-alone mode is strongly dependent on residual hearing levels, lexical knowledge, and speech-production abilities. Further applications of the model provided an estimate of the effect of each component on the overall speech-perception score for each child.

Practice chains of production and consumption : mediatized practices across social fields

The argument developed in this paper is that a focus on practice provides some resolutions to methodological problems facing Bourdieuian scholarship in education. In order to develop Bourdieu's work on practice to account for the interactions between practices, this paper presents a conceptualization of practice as chains of production and consumption. The first part of the paper reviews the account of practice offered by Bourdieu both embedded in practice games and as field effects. The second part of the paper introduces practice chains of production and consumption as a way to conceptualize practice by drawing on a case involving print journalists' involvement with policy makers over the course of an Australian policy review. The final section presents a discussion of this conceptualization and highlights the potential of the concept for further research in understanding the processes of educational policy development.

Development of strategies to increase commercial production of mohair and cashmere in Australia

We aimed to identify impediments to investing into mohair and cashmere production and to suggest programs and strategies to attract investors. Targeted interviews of people focussed on attributes of an investment opportunity. Analysis differentiated views of small and large-scale producers and those not involved in these industries. Potential investors into mohair and cashmere make decisions based on the compatibility of the enterprise to their farm system, the technical, financial and market feasibility of the enterprise and its comparative advantage with other possible courses of action. They are sceptical of information coming from within these industries that is not sufficiently supported by fact. There are many implications from these findings including the need for the industries to: understand the investment decision process; provide objective financial and benchmarking data; make information more accessible; overcome resistance to these industries; and increase the visibility of the industries.

Water quality, bacterial flora and production in shrimp farms in Sri Lanka

This study investigated the possibilities of improvement in the brackish water shrimp culture industry in Sri Lanka. Feeding rates could be further reduced without negative effect on shrimp growth while improving effluent water quality. Improvements of feed quality and pond management practices were also suggested.

Culture clash : artistic production and the school environment

Artists-in-schools programs involving contemporary art practices can be transformational for the participants when environmental considerations are integral to the planning and structure of the project and both the form and content of the program are reflected upon critically.

MRP-production planning in agile manufacturing

The research studied a production planning problem in a manufacturing firm. Some production planning software was developed that enabled the efficient and rapid reproduction of an optimum production forecast. Not only was the production cost reduced but a significant length of planning time cn be saved using the software.

Decision support tool for production planning of a machining line

A decision support tool for production planning was developed to perform the difficult and time consuming task of allocating resources within the industrial partner's machining line, consisting of identical Computerized Numerically Controlled machines. The production-planning tool identified significant labour savings in a number of the industrial partner's production plans.

The viability of commercial tomato production in the Autopot system

An investigation of the viability of commercial tomato production using the Autopot growing system in Australia. The Autopot system is a relatively new hydroponic production system technology that is being introduced onto the market in competition with traditional systems. Although commercial tomato production was found to be significantly more water and nutrient efficient in the Autopot system than in a traditional open system, yields were significantly lower. Financial modelling shows that tomato production in this system would not be commercially viable in Australia for a typical tomato growing venture under current conditions.

Innovative analytical chemistry for monitoring wine production

This study monitored concentration changes in the major constituents of wine during its production, through the development of new and innovative methodologies for a range of analytical instrumentation. Chemometrics (statistical analysis) was employed to enhance data interpretation, which provided insight into the reactions occurring between the key chemical species present.

Dynamics of endogenous food production in Cherax destructor Clark culture ponds

This study examined endogenous food production in crayfish culture ponds and the pond dynamics resulting from the interactions of pond bottom and water column parameters under a crop flooding strategy.