Metal-free graphitic carbon nitride as mechano-catalyst for hydrogen evolution reaction

Graphitic carbon nitride (g-C3N4), as a promising metal-free catalyst for photo-catalytic and electrochemical water splitting, has recently attracted tremendous research interest. However, the underlying catalytic mechanism for the hydrogen evolution reaction (HER) is not fully understood. By using density functional theory calculations, here we have established that the binding free energy of hydrogen atom (ΔGH∗0) on g-C3N4 is very sensitive to mechanical strain, leading to substantial tuning of the HER performance of g-C3N4 at different coverages. The experimentally-observed high HER activity in N-doped graphene supported g-C3N4 (Zheng et al., 2014) is actually attributed to electron-transfer induced strain. A more practical strategy to induce mechanical strain in g-C3N4 is also proposed by doping a bridge carbon atom in g-C3N4 with an isoelectronic silicon atom. The calculated ΔGH∗0 on the Si-doped g-C3N4 is ideal for HER. Our results indicate that g-C3N4 would be an excellent metal-free mechano-catalyst for HER and this finding is expected to guide future experiments to efficiently split water into hydrogen based on the g-C3N4 materials.

Towards a quantitative theory of epidermal calcium profile formation in unwounded skin

We propose and mathematically examine a theory of calcium profile formation in unwounded mammalian epidermis based on: changes in keratinocyte proliferation, fluid and calcium exchange with the extracellular fluid during these cells' passage through the epidermal sublayers, and the barrier functions of both the stratum corneum and tight junctions localised in the stratum granulosum. Using this theory, we develop a mathematical model that predicts epidermal sublayer transit times, partitioning of the epidermal calcium gradient between intracellular and extracellular domains, and the permeability of the tight junction barrier to calcium ions. Comparison of our model's predictions of epidermal transit times with experimental data indicates that keratinocytes lose at least 87% of their volume during their disintegration to become corneocytes. Intracellular calcium is suggested as the main contributor to the epidermal calcium gradient, with its distribution actively regulated by a phenotypic switch in calcium exchange between keratinocytes and extracellular fluid present at the boundary between the stratum spinosum and the stratum granulosum. Formation of the extracellular calcium distribution, which rises in concentration through the stratum granulosum towards the skin surface, is attributed to a tight junction barrier in this sublayer possessing permeability to calcium ions that is less than 15 nm/s in human epidermis and less than 37 nm/s in murine epidermis. Future experimental work may refine the presented theory and reduce the mathematical uncertainty present in the model predictions.

Boys 'doing' and 'undoing' media education : new possibilities for theory and practice

The purpose of this study is to investigate how secondary school media educators might best meet the needs of students who prefer practical production work to ‘theory’ work in media studies classrooms. This is a significant problem for a curriculum area that claims to develop students’ media literacies by providing them with critical frameworks and a metalanguage for thinking about the media. It is a problem that seems to have become more urgent with the availability of new media technologies and forms like video games. The study is located in the field of media education, which tends to draw on structuralist understandings of the relationships between young people and media and suggests that students can be empowered to resist media’s persuasive discourses. Recent theoretical developments suggest too little emphasis has been placed on the participatory aspects of young people playing with, creating and gaining pleasure from media. This study contributes to this ‘participatory’ approach by bringing post structuralist perspectives to the field, which have been absent from studies of secondary school media education. I suggest theories of media learning must take account of the ongoing formation of students’ subjectivities as they negotiate social, cultural and educational norms. Michel Foucault’s theory of ‘technologies of the self’ and Judith Butler’s theories of performativity and recognition are used to develop an argument that media learning occurs in the context of students negotiating various ‘ethical systems’ as they establish their social viability through achieving recognition within communities of practice. The concept of ‘ethical systems’ has been developed for this study by drawing on Foucault’s theories of discourse and ‘truth regimes’ and Butler’s updating of Althusser’s theory of interpellation. This post structuralist approach makes it possible to investigate the ways in which students productively repeat and vary norms to creatively ‘do’ and ‘undo’ the various media learning activities with which they are required to engage. The study focuses on a group of year ten students in an all boys’ Catholic urban school in Australia who undertook learning about video games in a three-week intensive ‘immersion’ program. The analysis examines the ethical systems operating in the classroom, including formal systems of schooling, informal systems of popular cultural practice and systems of masculinity. It also examines the students’ use of semiotic resources to repeat and/or vary norms while reflecting on, discussing, designing and producing video games. The key findings of the study are that students are motivated to learn technology skills and production processes rather than ‘theory’ work. This motivation stems from the students’ desire to become recognisable in communities of technological and masculine practice. However, student agency is not only possible through critical responses to media, but through performative variation of norms through creative ethical practices as students participate with new media technologies. Therefore, the opportunities exist for media educators to create the conditions for variation of norms through production activities. The study offers several implications for media education theory and practice including: the productive possibilities of post structuralism for informing ways of doing media education; the importance of media teachers having the autonomy to creatively plan curriculum; the advantages of media and technology teachers collaborating to draw on a broad range of resources to develop curriculum; the benefits of placing more emphasis on students’ creative uses of media; and the advantages of blending formal classroom approaches to media education with less formal out of school experiences.

Application of a continuum theory to vertical vibrations of a layer of granular material

Many interesting phenomena have been observed in layers of granular materials subjected to vertical oscillations; these include the formation of a variety of standing wave patterns, and the occurrence of isolated features called oscillons, which alternately form conical heaps and craters oscillating at one-half of the forcing frequency. No continuum-based explanation of these phenomena has previously been proposed. We apply a continuum theory, termed the double-shearing theory, which has had success in analyzing various problems in the flow of granular materials, to the problem of a layer of granular material on a vertically vibrating rigid base undergoing vertical oscillations in plane strain. There exists a trivial solution in which the layer moves as a rigid body. By investigating linear perturbations of this solution, we find that at certain amplitudes and frequencies this trivial solution can bifurcate. The time dependence of the perturbed solution is governed by Mathieu’s equation, which allows stable, unstable and periodic solutions, and the observed period-doubling behaviour. Several solutions for the spatial velocity distribution are obtained; these include one in which the surface undergoes vertical velocities that have sinusoidal dependence on the horizontal space dimension, which corresponds to the formation of striped standing waves, and is one of the observed patterns. An alternative continuum theory of granular material mechanics, in which the principal axes of stress and rate-of-deformation are coincident, is shown to be incapable of giving rise to similar instabilities.

Questions of English : ethics, aesthetics, rhetoric, and the formation of the subject in England, Australia and the United States

The impact and content of English as a subject on the curriculum is once more the subject of lively debate. Questions of English sets out to map the development of English as a subject and how it has come to encompass the diversity of ideas that currently characterise it. Drawing on a combination of historical analysis and recent research findings Robin Peel, Annette Patterson and Jeanne Gerlach bring together and compare important new insights on curriculum development and teaching practice from England, Australia and the United States. They also discuss the development of teacher training, highlighting the variety of ways in which teachers build their own beliefs and knowledge about English.

A grounded theory study of technology appropriation in anaesthesia

The human-technology nexus is a strong focus of Information Systems (IS) research; however, very few studies have explored this phenomenon in anaesthesia. Anaesthesia has a long history of adoption of technological artifacts, ranging from early apparatus to present-day information systems such as electronic monitoring and pulse oximetry. This prevalence of technology in modern anaesthesia and the rich human-technology relationship provides a fertile empirical setting for IS research. This study employed a grounded theory approach that began with a broad initial guiding question and, through simultaneous data collection and analysis, uncovered a core category of technology appropriation. This emergent basic social process captures a central activity of anaesthestists and is supported by three major concepts: knowledge-directed medicine, complementary artifacts and culture of anaesthesia. The outcomes of this study are: (1) a substantive theory that integrates the aforementioned concepts and pertains to the research setting of anaesthesia and (2) a formal theory, which further develops the core category of appropriation from anaesthesia-specific to a broader, more general perspective. These outcomes fulfill the objective of a grounded theory study, being the formation of theory that describes and explains observed patterns in the empirical field. In generalizing the notion of appropriation, the formal theory is developed using the theories of Karl Marx. This Marxian model of technology appropriation is a three-tiered theoretical lens that examines appropriation behaviours at a highly abstract level, connecting the stages of natural, species and social being to the transition of a technology-as-artifact to a technology-in-use via the processes of perception, orientation and realization. The contributions of this research are two-fold: (1) the substantive model contributes to practice by providing a model that describes and explains the human-technology nexus in anaesthesia, and thereby offers potential predictive capabilities for designers and administrators to optimize future appropriations of new anaesthetic technological artifacts; and (2) the formal model contributes to research by drawing attention to the philosophical foundations of appropriation in the work of Marx, and subsequently expanding the current understanding of contemporary IS theories of adoption and appropriation.

Minimising transport disadvantage to support knowledge city formation : applying the capability approach to select indicators

Purpose–The aims of this paper are to demonstrate the application of Sen’s theory of well-being, the capability approach; to conceptualise the state of transportation disadvantage; and to underpin a theoretical sounds indicator selection process. Design/methodology/approach–This paper reviews and examines various measurement approaches of transportation disadvantage in order to select indicators and develop an innovative framework of urban transportation disadvantage. Originality/value–The paper provides further understanding of the state of transportation disadvantage from the capability approach perspective. In addition, building from this understanding, a validated and systematic framework is developed to select relevant indicators. Practical implications –The multi-indicator approach has a high tendency to double count for transportation disadvantage, increase the number of TDA population and only accounts each indicator for its individual effects. Instead, indicators that are identified based on a transportation disadvantage scenario will yield more accurate results. Keywords – transport disadvantage, the capability approach, accessibility, measuring urban transportation disadvantage, indicators selection Paper type – Academic Research Paper

The formation of, and change in, the psychological contracts of graduates entering the Queensland public sector

The workplace is evolving and the predicted impact of demographic changes (Salt, 2009; Taylor, 2005) has seen organisations focus on strategic workforce planning. As part of this, many organisations have established or expanded formalised graduate programs to attract graduates and transition them effectively into organisations (McDermott, Mangan, & O'Connor, 2005; Terjesen, Freeman, & Vinnicombe, 2007). The workplace context is also argued to be changing because of the divergence in preferences and priorities across the different generations in the workplace - a topic which is prolific in the popular culture media but is yet to be fully developed in the academic literature (Jorgenson, 2003). The public sector recruits large numbers of graduates and maintains well established graduate programs. Like the workplace context, the public sector is seen to be undergoing a transition to more closely align its practices and processes with that of the private sector (Haynes & Melville Jones, 1999; N. Preston, 1995). Consequently, questions have been raised as to how new workforce entrants see the public sector and its associated attractiveness as an employment option. This research draws together these issues and reviews the formation of, and change in, the psychological contracts of graduates across ten Queensland public sector graduate programs. To understand the employment relationship, the theories of psychological contract and public service motivation are utilised. Specifically, this research focuses on graduates' and managers' expectations over time, the organisational perspective of the employment relationship and how ideology influences graduates' psychological contract. A longitudinal mixed method design, involving individual interviews and surveys, is employed along with significant researcher-practitioner collaboration throughout the research process. A number of important qualitative and quantitative findings arose from this study and there was strong triangulation between results from the two methods. Prior to starting with the organisation, graduates found it difficult to articulate their expectations; however, organisational experience rapidly brought these to the fore. Of the expectations that became salient, most centred on their relationship with their supervisor. Without experience and quality information on which to base their expectations, graduates tended to over-rely on sectoral stereotypes which negatively impacted their psychological contracts. Socialisation only limited affected graduates' psychological contracts and public service motivation. The graduate survey, measured thrice throughout the first 12 months of the graduate program, revealed that the psychological contract and public service motivation results followed a similar trajectory of beginning at mediocre levels, declining between times one and two and increasing between times two and three (although this is not back to original levels). Graduates attributed these to a number of sectoral, organisational, team, supervisory and individual factors. On a theoretical level, this research provides support for the notion of ideology within the psychological contract although it raises some important questions about how it is conceptualised. Additionally, support is given for the manager to be seen as the primary organisational counterpart to the employee in future theoretical and practical work. The research also argues to extend current notions of time within the psychological contract as this seems to be the most divergent and combustible issue across the generations in terms of how the workplace is perceived. A number of practical implications also transpire from the study and the collaborative foundation was highly successful. It is anticipated that this research will make a meaningful contribution to both the theory and practice of the employment relationship with particular regard to graduates entering the public sector.

Theoretical analysis of serrated chip formation based on ideal models in high speed cutting

In this paper, two ideal formation models of serrated chips, the symmetric formation model and the unilateral right-angle formation model, have been established for the first time. Based on the ideal models and related adiabatic shear theory of serrated chip formation, the theoretical relationship among average tooth pitch, average tooth height and chip thickness are obtained. Further, the theoretical relation of the passivation coefficient of chip's sawtooth and the chip thickness compression ratio is deduced as well. The comparison between these theoretical prediction curves and experimental data shows good agreement, which well validates the robustness of the ideal chip formation models and the correctness of the theoretical deducing analysis. The proposed ideal models may have provided a simple but effective theoretical basis for succeeding research on serrated chip morphology. Finally, the influences of most principal cutting factors on serrated chip formation are discussed on the basis of a series of finite element simulation results for practical advices of controlling serrated chips in engineering application.

To bound or not to bound: preliminary Theory of Time Bounds Specification in strategic alliances

This article augments Resource Dependence Theory with Real Options reasoning in order to explain time bounds specification in strategic alliances. Whereas prior work has found about a 50/50 split between alliances that are time bound and those that are open-ended, their substantive differences and antecedents are ill understood. To address this, we suggest that the two alliance modes present different real options trade-offs in adaptation to environmental uncertainty: ceteris paribus, time-bound alliances are likely to provide abandonment options over open-ended alliances, but require additional investments to extend the alliance when this turns out to be desirable after formation. Open-ended alliances are likely to provide growth options over open-ended alliances, but they demand additional effort to abandon the alliance if post-formation circumstances so desire. Therefore, we expect time bounds specification to be a function of environmental uncertainty: organizations in more uncertain environments will be relatively more likely to place time bounds on their strategic alliances. Longitudinal archival and survey data collected amongst 39 industry clusters provides empirical support for our claims, which contribute to the recent renaissance of resource dependence theory by specifying the conditions under which organizations choose different time windows in strategic partnering.

Scenes, quarters and clusters : new experiments in the formation and governance of creative places in China

This thesis examines the formation and governance patterns of the social and spatial concentration of creative people and creative business in cities. It develops a typology for creative places, adding the terms 'scene' and 'quarter' to 'clusters', to fill in the literature gap of partial emphasis on the 'creative clusters' model as an organising mechanism for regional and urban policy. In this framework, a cluster is the gathering of firms with a core focus on economic benefits; a quarter is the urban milieu usually driven by a growth coalition consisting of local government, real estate agents and residential communities; and a scene is the spontaneous assembly of artists, performers and fans with distinct cultural forms. The framework is applied to China, specifically to Hangzhou – a second-tier city in central eastern China that is ambitious to become a 'national cultural and creative industries centre'. The thesis selects three cases – Ideal & Silian 166 Creative Industries Park, White-horse Lake Eco-creative City and LOFT49 Creative Industries Park – to represent scene, quarter and cluster respectively. Drawing on in-depth interviews with initiators, managers and creative professionals of these places, together with extensive documentary analysis, the thesis investigates the composition of actors, characteristics of the locality and the diversity of activities. The findings illustrate that, in China, planning and government intervention is the key to the governance of creative space; spontaneous development processes exist, but these need a more tolerant environment, a greater diversity of cultural forms and more time to develop. Moreover, the main business development model is still real estate based: this model needs to incorporate more mature business models and an enhanced IP protection system. The thesis makes a contribution to literature on economic and cultural geography, urban planning and creative industries theory. It advocates greater attention to self-management, collaborative governance mechanisms and business strategies for scenes, quarters and clusters. As intersections exist in the terms discussed, a mixed toolkit of the three models is required to advance the creative city discourse in China.

Formation of single-walled carbon nanotube via the interaction of graphene nanoribbons : ab initio density functional calculations

The interaction of bare graphene nanoribbons (GNRs) was investigated by ab initio density functional theory calculations with both the local density approximation (LDA) and the generalized gradient approximation (GGA). Remarkably, two bare 8-GNRs with zigzag-shaped edges are predicted to form an (8, 8) armchair single-wall carbon nanotube (SWCNT) without any obvious activation barrier. The formation of a (10, 0) zigzag SWCNT from two bare 10-GNRs with armchair-shaped edges has activation barriers of 0.23 and 0.61 eV for using the LDA and the revised PBE exchange correlation functional, respectively, Our results suggest a possible route to control the growth of specific types SWCNT via the interaction of GNRs.

Reconnection : a contemporary development in cultural landscape theory contributing to rehabilitation strategies for Australian open-cut coal mining landscapes

A value-shift began to influence global political thinking in the late 20th century, characterised by recognition of the need for environmentally, socially and culturally sustainable resource development. This shift entailed a move away from thinking of ‘nature’ and ‘culture’ as separate entities – the former existing to serve the latter – toward the possibility of embracing the intrinsic worth of the nonhuman world. Cultural landscape theory recognises ‘nature’ as at once both ‘natural’, and a ‘cultural’ construct. As such, it may offer a framework through which to progress in the quest for ‘sustainable development’. This study makes a contribution to this quest by asking whether contemporary developments in cultural landscape theory can contribute to rehabilitation strategies for Australian open-cut coal mining landscapes. The answer is ‘yes’. To answer the research question, a flexible, ‘emergent’ methodological approach has been used, resulting in the following outcomes. A thematic historical overview of landscape values and resource development in Australia post-1788, and a review of cultural landscape theory literature, contribute to the formation of a new theoretical framework: Reconnecting the Interrupted Landscape. This framework establishes a positive answer to the research question. It also suggests a method of application within the Australian open-cut coal mining landscape, a highly visible exemplar of the resource development landscape. This method is speculatively tested against the rehabilitation strategy of an operating open-cut coal mine, concluding with positive recommendations to the industry, and to government.

Governing self : SNSs as tools for self-formation

This thesis investigates how modern individuals relate to themselves and others in the service of shaping their ethical conduct and governing themselves. It considers the use of online social networking sites (SNSs) as one particular practice through which people manage their day-to-day conduct and understandings of self. Current research on the use of SNSs has conceptualised them as tools for communication, information-sharing and self-presentation. This thesis suggests a different way of thinking about these sites as tools for self-formation. A Foucaultian genealogical, historical and problematising approach is applied in order to explore processes of subjectivation and historical backgrounds involved in the use of SNSs. This is complimented with an ANT-based understanding of the role that technologies play in shaping human action. Drawing new connections between three factors will show how they contribute to the ways in which people become selves today. These factors are, one, the psychologisation and rationalisation of modern life that lead people to confess and talk about themselves in order to improve and perfect themselves, two, the transparency or publicness of modern life that incites people to reveal themselves constantly to a public audience and, three, the techno-social hybrid character of Western societies. This thesis will show how some older practices of self-formation have been translated into the context of modern technologised societies and how the care of self has been reinvigorated and combined with the notion of baring self in public. This thesis contributes a different way of thinking about self and the internet that does not seek to define what the modern self is and how it is staged online but rather accounts for the multiple, contingent and historically conditioned processes of subjectivation through which individuals relate to themselves and others in the service of governing their daily conduct.

Formation energies of low-indexed surfaces of tin dioxide terminated by nonmetals

The surface formation energies of four low-indexed surfaces, including (001), (100), (110) and (011), of tin dioxide (SnO2) terminated by nonmetals (H, N, O, F, Cl, Br, and I) have been studied with the frameworks of density functional theory. A strong dependence of relative surface stabilities on surface atoms has been presented based on the calculations. Several instructions, in particular the selection of specific precursors and morphology controlling agents, have been further illustrated as a guideline for experimentalists.