39 resultados para Band gaps

em Deakin Research Online - Australia


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Optoelectronic Devices A captivating peculiarity of GaInN alloys is a tunable band gap, depending on the Ga/In ratio, where the pure nitrides are bright yellow (GaN) or dark blue (InN). Gax In1-x N nanoparticles were prepared by a bottom-up approach (the urea glass route). The incorporation of an increasing amount of indium in the GaN structure is indicated by different colors (i.e., different band gaps), and the alloys are further investigated by TEM and optical microscopy. More information can be found in the Full Paper by C. Giordano et al. on page 18976 ff.

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Two experiments were conducted to clarify the roles of grain size, solute carbon and strain in determining the recrystallization textures of cold-rolled and annealed steels. In the first experiment, samples of coarse-grained low-carbon (LC) and interstitial-free (IF) steels were cold-rolled to a 75% reduction in thickness. One sample from each steel was polished and cold-rolled an additional 5%, while the remaining samples were annealed for various times at 650°C. In the second experiment, three samples from a commercial LC steel sheet were rolled 70% at 300°C. Two of the samples were given a further rolling reduction of 5% of the original thickness, with one of the samples being given this additional reduction at 300°C and the other at room temperature. Goss recrystallization textures are strengthened by coarse initial grain sizes, the presence of solute carbon and rolling at a temperature where dynamic strain ageing occurs, but are weakened by additional rolling beyond a reduction of 70%, especially when this extra rolling is conducted at a temperature where dynamic strain ageing does not occur. Characterization of key features of the deformed and recrystallized steels using optical microscopy, scanning electron microscopy (SEM) and electron back-scatter diffraction (EBSD) supports a rationale for these effects based on the repeated activation and deactivation of shear bands and the influence of solute carbon and dynamic strain ageing on the operating life of the bands and the accumulation of strain within them.

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In recent years, organisations have been increasingly developing web systems as portals through which B2C or B2B eCommerce is conducted. Many such systems suffer from inadequacy in function, form and quality. While such deficiencies are quite commonly encountered in traditional software systems, in the case of web systems, the problems are magnified by the emerging gaps in designers' intentions and the expectation of a global, and frequently grossly misunderstood, user. In this paper we therefore present an approach to investigating the gaps in perceptions between web developer’s intentions and end-users expectations and the subsequent use of web system features. Furthermore, we empirically investigated B2C web systems and determined several useful approaches to practical evaluation of the degree of cohesion between designer and user views of the system.

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Can book debts be subject to a fixed charge? This question was considered by the House of Lords in National Westminster Bank v. Spectrum Plus Limited [2005] UKHL 41 where the full House was against the idea of a fixed charge on book debts and insisted that only a floating charge had been created. The law in this area is still vague and uncertain in Australia. This paper argues that the financiers and the companies should be given the freedom to decide how they wish to structure their charge documents. The paper sets out to argue that, in respect to the use of book debts as security for a loan, the only way for both the financiers and the companies to do business is to create a sustained workable fixed charge or even multiple fixed and floating charge on book debts. The author explains how this could be possible and how the proposed model would not deny the statutory priority rights of the preferential creditors.

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Aims & rationale/Objectives : Hypercholesterolaemia accounts for 11.6% of total deaths and 6.2% of the disability burden for the Australian population.1 This paper reports population lipid profiles for three rural Australian populations, and assesses evidence-treatment gaps against the most recent (2005-2007) Australian guidelines.

Methods :
Three population surveys were undertaken in the Greater Green Triangle. 3,320 adults aged 25-74 yrs were randomly selected using age/gender stratified electoral roll samples and of these 1563 subjects participated in the survey. Anthropometric, clinical and self-administered questionnaire data relating to chronic disease risk were collected in accordance with the WHO MONICA protocol.2 A detailed investigation of dyslipidaemia was included.

Principal findings : All required data was available for 1255 participants. Age-standardised mean total cholesterol (TC), triglycerides, LDL cholesterol and HDL cholesterol concentrations were 5.36 mmol/l, 1.42 mmol/l, 3.23 mmol/l and 1.48 mmol/l, respectively. Amongst those taking lipid-lowering medication, just 11% categorised as secondary prevention/diabetes, and 39% as primary prevention, achieved all lipid targets. In the 20% of untreated participants at high risk of a primary cardiovascular event, 26% were aware of their hypercholesterolaemia and just 2% achieved all lipid targets (2.8% achieved TC?5.5 mmol, 8.5% achieved LDL<3.5 mmol/l). 11.2% of the overall population used lipid-lowering medication (95% was statin monotherapy).

Implications : Most adults do not achieve their target lipid profile. This paper identifies the subpopulations and lipid components which need to be targeted for future interventions. It also identifies substantial evidence-treatment gaps which should be addressed to help improve lipid profiles at a population level.

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Aims & Rationale/Objectives
The aim is to establish the frequency of counselling by general practitioners (GPs) and community pharmacists (CPs) for patients with uncontrolled CVD risk factors. This will identify conditions for which CPs might collaborate with GPs in addressing evidence-treatment gaps.

Methods
A population survey undertaken in the Wimmera region of Victoria in 2006. 1425 adults aged 25-84 yrs were randomly selected using age/sex stratified electoral role samples. A representative 723 participants were recruited.

Principal Findings
Data on GP and CP visits were available for 694 participants. Overall, participants visited GPs 4.6 times and CPs 6.0 times/annum. However, one third of participants never consulted a pharmacist in 12 months compared to just 11.5% for GPs. Among obese patients (BMI ?? 30), the average number of visits/annum was 4.5 to GPs and 6.8 to CPs. The equivalent numbers were 5.6 and 8.6 respectively for those with systolic BP ?? 140 mmHg; 3.7 and 5.5 for total cholesterol > 5.0 mmol/L; and, 6.7 and 14.6 for patients with random blood glucose concentrations ?? 7.0 mmol/L.

Implications

People with suboptimal status for most common CVD risk factor are counselled frequently by CPs. A coordinated approach with GPs to the delivery of cardiovascular health promotion could provide valuable reinforcement of key messages and offers greater opportunity to identify at-risk individuals. Acknowledgements: KM is a pharmacist-academic at Greater Green Triangle UDRH, a position funded by the Department of Health and Ageing through the Rural and Remote Pharmacy Workforce Development Program

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The Osoyoos Indian Band case study signals the beginning of a PhD research project that will take approximately three years to complete. Taken in isolation, the objectives for the Osoyoos case study are modest. We want to refine our theoretical model and improve the case study protocol before embarking on a set of 5 case studies to explore Indigenous entrepreneurship; what it is, what communities do to succeed and a generalized definition of a successful venture from an Indigenous Canadian perspective.

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Zebra finches have previously been found to have preferences for particular colours of both natural and artificial traits among opposite sex conspecifics. For example, in some studies female zebra finches preferred males wearing red leg bands to orange-banded and unbanded birds and rejected light green-banded males. In other studies, females also preferred males with red beaks to orange-beaked males. However, several authors have failed to replicate these results. We show that females may fail to show a colour preference because of the absence or removal of ultraviolet light under experimental conditions. In mate-choice trials, females observing males through filters that transmitted ultraviolet preferred red-banded males but where females viewed males through ultraviolet-blocking filters, no such preference was observed. Further investigation revealed that the lack of a colour preference when ultraviolet was absent was probably due to the change in overall appearance of the bird, rather than the change in appearance of the rings themselves. This work highlights the importance of proper consideration of the sensory capabilities of animals in experimental design, particularly with regard to the role of ultraviolet light in avian colour perception. (C) 1997 The Association for the Study of Animal Behaviour.

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This dissertation reports on a study of music making in a band of the Australian Army Band Corps. The thesis of the dissertation is how the world views of the soldier-musicians of the Australian Army Band, Kapooka, are constructed in the context of their work in military music performance. In arguing this thesis, the author provides a brief history of military music in Australia, and - demonstrates how rank and military discipline intersect with music making in the lived experience of the soldier-musicians; - explores how the dichotomy between music making as a craft and music making as art is resolved in a setting where the employer regards music making as a trade, while the soldier-musicians strive to meet artistic goals; - demonstrates how successful music making and successful soldiering are both forms of work which depend upon effective collective action; - demonstrates that while military bands play the widest repertoire of musical styles of any Western music ensemble, the styles converge toward a homogenous, eclectic, military band performance style: and - explores how military music, which may have limited intrinsic interest, in certain ceremonial settings may link with other visual and auditory symbol systems to generate profound meaning both for the soldier-musicians themselves and for their audiences. The study examines the processes by which the world views of soldier-musicians are shaped by the institutional context in which they work, as they participate in a music tradition which has been a powerful agent in the shaping of Australian patriotic traditions. The study uses a naturalistic participant observation methodology. The author worked as an honorary guest civilian member of the band’s trombone section to collect data in the form of fieldnotes and interviews. Data analysis and interpretation was made according to the tenets of grounded theory. Evidence in the form of first hand accounts from the perspective of the researcher and from the soldier-musicians themselves is employed to generate both emic and etic understandings. An understanding of a music culture from the participant's point of view is a central concern of the study.