988 resultados para Solution Culture
The electrochemical corrosion behaviour of quaternary gold alloys when exposed to 3.5% NaCl solution
Resumo:
Lower carat gold alloys, specifically 9 carat gold alloys, containing less than 40 % gold, and alloying additions of silver, copper and zinc, are commonly used in many jewellery applications, to offset high costs and poor mechanical properties associated with pure gold. While gold is considered to be chemically inert, the presence of active alloying additions raises concerns about certain forms of corrosion, particularly selective dissolution of these alloys. The purpose of this study was to systematically study the corrosion behaviour of a series of quaternary gold–silver–copper–zinc alloys using dc potentiodynamic scanning in saline (3.5 % NaCl) environment. Full anodic/cathodic scans were conducted to determine the overall corrosion characteristics of the alloy, followed by selective anodic scans and subsequent morphological and compositional analysis of the alloy surface and corroding media to determine the extent of selective dissolution. Varying degrees of selective dissolution and associated corrosion rates were observed after anodic polarisation in 3.5 % NaCl, depending on the alloy composition. The corrosion behaviour of the alloys was determined by the extent of anodic reactions which induce (1) formation of oxide scales on the alloy surface and or (2) dissolution of Zn and Cu species. In general, the improved corrosion characteristics of alloy #3 was attributed to the composition of Zn/Cu in the alloy and thus favourable microstructure promoting the formation of protective oxide/chloride scales and reducing the extent of Cu and Zn dissolution.
Promoting a more positive traffic safety culture in Australia : lessons learnt and future directions
Resumo:
Adopting a traffic safety culture approach, this paper identifies and discusses the ongoing challenge of promoting the road safety message in Australia. It is widely acknowledged that mass media and public education initiatives have played a critical role in the significant positive changes witnessed in community attitudes to road safety in the last three to four decades. It could be argued that mass media and education have had a direct influence on behaviours and attitudes, as well as an indirect influence through signposting and awareness raising functions in conjunction with enforcement. Great achievements have been made in reducing fatalities on Australia’s roads; a concept which is well understood among the international road safety fraternity. How well these achievements are appreciated by the general Australian community however, is not clear. This paper explores the lessons that can be learnt from successes in attitudinal and behaviour change in regard to seatbelt use and drink driving in Australia. It also identifies and discusses key challenges associated with achieving further positive changes in community attitudes and behaviours, particularly in relation to behaviours that may not be perceived by the community as dangerous, such as speeding and mobile phone use while driving. Potential strategies for future mass media and public education campaigns to target these challenges are suggested, including ways of harnessing the power of contemporary traffic law enforcement techniques, such as point-to-point speed enforcement and in-vehicle technologies, to help spread the road safety message.
Resumo:
Now is an opportune moment to consider the shifts in youth and popular culture that are signalled by texts that are being read and viewed by young people. In a world seemingly compromised by climate change, political and religious upheavals and economic irresponsibility, and at a time of fundamental social change, young people are devouring fictional texts that focus on the edges of identity, the points of transition and rupture, and the assumption of new and hybrid identities. This book draws on a range of international texts to address these issues, and to examine the ways in which key popular genres in the contemporary market for young people are being re-defined and re-positioned in the light of urgent questions about the environment, identity, one's place in the world, and the fragile nature of the world itself. The key questions are: what are the shifts and changes in youth culture that are identified by the market and by what young people read and view? How do these texts negotiate the addressing of significant questions relating to the world today? Why are these texts so popular with young people? What are the most popular genres in contemporary best-sellers and films? Do these texts have a global appeal, and, if so, why? These over-arching themes and ideas are presented as a collection of inter-related essays exploring a rich variety of forms and styles from graphic novels to urban realism, from fantasy to dystopian writing, from epic narratives to television musicals. The subjects and themes discussed here reveal the quite remarkable diversity of issues that arise in youth fiction and the variety of fictional forms in which they are explored. Once seen as not as important as adult fiction, this book clearly demonstrates that youth fiction (and the popular appeal of this fiction) is complex, durable and far-reaching in its scope.
Resumo:
We come together as editors to prepare an introduction to this international volume at a time of economic turbulence, new uncertainties about the future, and a growing demand on the part of most governments for further alignment of education with the economy. Literacy, in particular, is in the vanguard, for literacy only too frequently is positioned as a proxy for education. What are the purposes of literacy teaching and how is it to be achieved? What counts as literacy in ‘new times,’ in ‘participatory culture’ where people ‘believe their contributions matter, and feel some degree of social connection with one another’ (Abrams and Merchant, Chapter 23)? How can everyone be included as critical citizens of the world in whatever definition of literacy we endorse? What fresh perspectives, new ways of thinking, and good ideas for the understanding of literacy are out there? What are the possibilities for the future? An exploration of these kinds of questions and their answers, however tentative, provides us, we believe, with our best defense against the uncertainties of our age. In some respects this is our overall purpose in the volume, to explore our understanding and future possibilities by bringing together critical reviews of the major theories, methods, and pedagogical advances that have taken place in the past 20 years in the field of literacy research at the primary/elementary school level. Each chapter in the volume is newly written for the Handbook while overall the book is intended to be a distillation of key thinking and theory which offers new directions for research in literacy. It aims to revisit current interpretations, make novel connections, frame new possibilities, and encourage researchers to pursue innovative and compelling lines of inquiry...
Resumo:
This paper offers a discussion on the “mundane” or quotidian aspects of that software which might at first glance seem to be a fine example of the extraordinary. It looks at game worlds in terms of an ancient human desire to articulate place in the world and pursues a design concept which resonates with this practice in order to enable a more mundane exploitation of such spatial representations: the claiming of place.
Resumo:
The Community Arts sector in Australia has a history of resistance. It has challenged hegemonic culture through facilitating grassroots creative production, contesting notions of artistic processes, and the role of the artist in society. This paper examines this penchant for resistance through the lens of contemporary digital culture, to establish that the sector is continuing to challenge dominant forms of cultural control. It then proposes that this enthusiasm and activity lacks ethical direction, describing it as feral to encompass the potential of current practices, while highlighting how a level of taming is needed in order to develop ethical approaches.
Resumo:
The application of layered double hydroxides (LDHs) and thermally activated LDHs for the removal of various fluorine (F-, BF-4), chlorine (Cl-,ClO-4), bromine (Br-, BrO-3) and iodine (I-, IO-3) species from aqueous solutions has been reviewed in this article. LDHs and thermally activated LDHs were able to significantly reduce the concentration of selected anions in laboratory scale experiments. The M2+:M3+ cation ratio of the LDH adsorbent was an important factor which influenced anion uptake. Though LDHs were able to remove some target anion species through anion exchange and surface adsorption thermal activation and reformation generally produced better results. The presence of competing anions including carbonate, phosphate and sulphate had a significant impact on uptake of the target anion as LDHs typically exhibit lower affinity towards monovalent anions compared to anions with multiple charges. The removal of fluoride and perchlorate from aqueous solution by a continuous flow system utilising fixed bed columns packed with LDH adsorbents has also been investigated. The adsorption capacity of the columns at breakpoint was heavily dependent on the flow rate and lower than result reported for the corresponding batch methods. There is still considerable scope for future research on numerous topics summarised in this article.
Resumo:
Paul O'Neill's book, 'The Culture of Curating and the Curating of Culture(s)provides a concise overview of how curating has changed art and how art has changed curating. The book is divided into three sections, each dealing with a key transitional development: (1) the historical development of curatorial discourse; (2) the influence of the Biennial phenomenon and, finally, (3) how art and curating have converged since the 1990s. This review discusses the publication as a significant contribution to the development of a curatorial history and discourse.
Resumo:
A recent success story of the Australian videogames industry is Brisbane based Halfbrick Studios, developer of the hit game for mobile devices, Fruit Ninja. Halfbrick not only survived the global financial crisis and an associated downturn in the Australian industry, but grew strongly, moving rapidly from developing licensed properties for platforms such as Game Boy Advance, Nintendo DS, and Playstation Portable (PSP) to becoming an independent developer and publisher of in-house titles, generating revenue both through App downloads and merchandise sales. Amongst the reasons for Halfbrick’s success is their ability to adaptively transform by addressing different technical platforms, user dynamics, business models and market conditions. Our ongoing case-study research from 2010 into Halfbrick’s innovation processes, culminating with some 10 semi-structured interviews with senior managers and developers, has identified a strong focus on workplace organisational culture, with staff reflecting that the company is a flat, team-based organisation devolving as much control as possible to the development teams directly, and encouraging a work-life balance in which creativity can thrive. The success of this strategy is evidenced through Halfbrick’s low staff turnover; amongst our interviewees most of the developers had been with the company for a number of years, with all speaking positively of the workplace culture and sense of creative autonomy they enjoyed. Interviews with the CEO, Shainiel Deo, and team leaders highlighted the autonomy afforded to each team and the organisation and management of the projects on which they work. Deo and team leaders emphasised the collaboration and communication skills they require in the developers that they employ, and that these characteristics were considered just as significant in hiring decisions as technical skills. Halfbrick’s developers celebrate their workplace culture and insist it has contributed to their capacity for innovation and to their commercial success with titles such as Fruit Ninja. This model of organisational management is reflected in both Stark’s (2009) idea of heterarchy, and Neff’s (2012) concept of venture labour, and provides a different perspective on the industry than the traditional political economy critique of precarious labour exploited by gaming conglomerates. Nevertheless, throughout many of the interviews and in our informal discussions with Halfbrick developers there is also a sense that this rewarding culture is quite tenuous and precarious in the context of a rapidly changing and uncertain global videogames industry. Whether such a workplace culture represents the future of the games industry, or is merely a ‘Prague Spring’ before companies such as Halfbrick are swallowed by traditional players’ remains to be seen. However, as the process of rapid and uncertain transformation plays out across the videogames industry, it is important to pay attention to emerging modes of organisation and workplace culture, even whilst they remain at the margins of the industry. In this paper we investigate Halfbrick’s workplace culture and ask how sustainable is this kind of rewarding and creative workplace?
Resumo:
We have developed a method to test the cytotoxicity of wound dressings, ointments, creams and gels used in our Burn Centre, by placing them on a permeable Nunc Polycarbonate cell culture insert, incubated with a monolayer of cells (HaCaTs and primary human keratinocytes). METHODS: We performed two different methods to determine the relative toxicity to cells. (1) Photo visualisation: The dressings or compounds were positioned on the insert's membrane which was placed onto the monolayer tissue culture plate. After 24 h the surviving adherent cells were stained with Toluidine Blue and photos of the plates were taken. The acellular area of non-adherent dead cells which had been washed off with buffer was measured as a percentage of the total area of the plate. (2) Cell count of surviving cells: After 24 h incubation with the test material, the remaining cells were detached with trypsin, spun down and counted in a Haemocytometer with Trypan Blue, which differentiates between live and dead cells. RESULTS: Seventeen products were tested. The least cytotoxic products were Melolite, White soft Paraffin and Chlorsig1% Ointment. Some cytotoxicity was shown with Jelonet, Mepitel((R)), PolyMem((R)), DuoDerm((R)) and Xeroform. The most cytotoxic products included those which contained silver or Chlorhexidine and Paraffin Cream a moisturizer which contains the preservative Chlorocresol. CONCLUSION: This in vitro cell culture insert method allows testing of agents without direct cell contact. It is easy and quick to perform, and should help the clinician to determine the relative cytotoxicity of various dressings and the optimal dressing for each individual wound.