Mild and cost-effective synthesis of iron fluoride-graphene nanocomposites for high-rate Li-ion battery cathodes

Exploring high performance cathode materials is essential to realize the adoption of Li-ion batteries for application in electric vehicles and hybrid electric vehicles. FeF3, as a typical iron-based fluoride, has been attracting considerable interest due to both the high electromotive force value of 2.7 V and the high theoretical capacity of 237 mA h g_1 (1e_ transfer). In this study, we report a facile lowtemperature solution phase approach for synthesis of uniform iron fluoride nanocrystals on reduced graphene sheets stably suspended in ethanol solution. The resulting hybrid of iron fluoride nanocrystals and graphene sheets showed high specific capacity and high rate performance for iron fluoride type cathode materials. High stable specific capacity of about 210 mA h g_1 at a current density of 0.2 C was achieved, which is much higher than that of LiFePO4 cathode material. Notably, these iron fluoride/ nanocomposite cathode materials demonstrated superior rate capability, with discharge capacities of 176, 145 and 113 mA h g_1 at 1, 2 and 5 C, respectively.

Problem and solution trees : a practical approach for identifying potential interventions to improve population nutrition

Population nutrition problems have a diversity of contributory factors and, ideally, multi-sectoral solutions should be developed by the relevant stakeholders, based on a common understanding of these factors. The problem and solution tree approach is a participatory process of working through the layers of determinants and then developing potential interventions for a specific issue, using the available data and expertise. We tailored this approach for non-communicable disease-related nutrition problems in Pacific Islands and applied it in several countries. The process led to the identification of a considerable range of determinants of unhealthy diets and potential interventions to improve the situation. This practical approach also offered the additional benefit of developing stakeholder awareness in the issues. Problem trees are a relatively simple tool to implement, easy to adapt to differing needs, can generate a wealth of information and can be more widely used.

Solution-focused work in individual academic development

There is one account in the literature of the application of a solution-focused approach to individual teaching development at university level (Devlin, 2003). The solution-focused approach is based on solution-focused brief therapy (SFBT). The current paper elaborates on the existing account, further outlining and illustrating the techniques that make up the solution-focused approach to academic development. The central tenets of SFBT-based academic development and the core components of solution-focused work are articulated. Current research in this area is outlined.

Synthesis of LiFePO4@carbon nanotube core-shell nanowires with a high-energy efficient method for superior lithium ion battery cathodes

A high-energy efficient method is developed for the synthesis of LiFePO4@CNT core-shell nanowire structures. The method consists of two steps: liquid deposition approach to prepare FePO4@CNT core-shell nanowires and solvothermal lithiation to obtain the LiFePO4@CNT core-shell nanowires at a low temperature. The solution phase method can be easily scaled up for commercial application. The performance of the materials produced by this method is evaluated in Li ion batteries. The one-dimensional LiFePO4@CNT nanowires offer a stable and efficient backbone for electron transport. The LiFePO4@CNT core-shell nanowires exhibit a high capacity of 132.8 mAh g^-1 at a rate of 0.2C, as well as high rate capability (64.4 mAh g^-1 at 20C) for Li ion storage.

Chemically induced phosphorescence from manganese(II) during the oxidation of various compounds by manganese(III), (IV) break and (VII) in acidic aqueous solutions

Chemiluminescence was observed during the manganese(III), (IV) and (VII) oxidations of sodium tetrahydroborate, sodium dithionite, sodium sulfite and hydrazine sulfate in acidic aqueous solution. From the corrected chemiluminescence spectra, the wavelengths of maximum emission were 689±5 and 734±5 nm when the reactions were performed in sodium hexametaphosphate and sodium dihydrogenorthophosphate/ orthophosphoric acid environments, respectively. The corrected phosphorescence spectrum of manganese(II) sulfate in a solution of sodium hexametaphosphate at 77 K exhibited two peaks with maxima at 688 and 730 nm. The chemical and spectroscopic evidence presented strongly supported the postulation that the emission was an example of solution-phase chemically induced phosphorescence of manganese(II) thereby, confirming earlier predictions that the chemiluminescence from acidic potassium permanganate reactions originated from an excited manganese(II) species.

New light from an old reagent: chemiluminescence from the reaction of potassium permanganate with sodium borohydride

When aqueous sodium borohydride (50 mM) is added to a solution of potassium permanganate (1mM, in sodium hexametaphosphate) at acidic pH, bright red-orange emission is easily visible in a darkened room. This chemiluminescence emission is due to an excited state of manganese (II) that undergoes solution phase phosphorescence and provides an excellent opportunity for students to explore the relationship between the initial oxidation state of the manganese and the likelihood of luminescence. Not surprisingly Mn(VII), Mn(IV) and Mn(III) all give rise to chemiluminescence where as Mn(II) fails to react.

Chemistry, spectroscopy and analytical applications of certain chemiluminescent reactions

Chemiluminescence, the production of light from a chemical reaction, has found widespread use in analytical chemistry. Both tris (2, 2’-bipyridyl) ruthenium (II) and acidic potassium permanganate are chemiluminescence reagents that have been employed for the determination of a diverse range of analytes. This thesis encompasses some fundamental investigations into the chemistry and spectroscopy of these chemiluminescence reactions as well as extending the scope of their analytical applications. Specifically, a simple and robust capillary electrophoresis chemiluminescence detection system for the determination of codeine, O6-methylcodeine and thebaine is described, based upon the reaction of these analytes with chemically generated tris(2,2'-bipyridyl)ruthenium(III) prepared in sulfuric acid (0.05 M). The reagent solution was contained in a glass detection cell, which also held both the capillary and the cathode. The resultant chemiluminescence was monitored directly using a photomultiplier tube mounted flush against the base of the detection cell. The methodology, which incorporated a field amplification sample introduction procedure, realised detection limits (3a baseline noise) of 5 x 10~8 M for both codeine and O6-methylcodeine and 1 x 10~7 M for thebaine. The relative standard deviations of the migration times and the peak areas for the three analytes ranged from 2.2 % up to 2.5 % and 1.9 % up to 4.6 % respectively. Following minor instrumental modifications, morphine, oripavine and pseudomorphine were determined based upon their reaction with acidic potassium permanganate in the presence of sodium polyphosphate. To ensure no migration of the permanganate anion occurred, the anode was placed at the detector end whilst the electroosmotic flow was reversed by the addition of hexadimethrine bromide (0.001% m/v) to the electrolyte. The three analytes were separated counter to the electroosmotic flow via their interaction with a-cyclodextrin. The methodology realised detection limits (3 x S/N) of 2.5 x 10~7 M for both morphine and oripavine and 5 x 10~7 M for pseudomorphine. The relative standard deviations of the migration times and the peak heights for the three analytes ranged from 0.6 % up to 0.8 % and 1.5% up to 2.1 % respectively. Further improvements were made by incorporating a co-axial sheath flow detection cell. The methodology was validated by comparing the results realised using this technique with those obtained by high performance liquid chromatography (HPLC), for the determination of both morphine and oripavine in seven industrial process liquors. A complimentary capillary electrophoresis procedure with UV-absorption detection was also developed and applied to the determination of morphine, codeine, oripavine and thebaine in nine process liquors. The results were compared with those achieved using a standard HPLC method. Although over eighty papers have appeared in the literature on the analytical applications of acidic potassium permanganate chemiluminescence, little effort has been directed towards identifying the origin of the luminescence. It was found that chemiluminescence was generated during the manganese(III), manganese(IV) and manganese(VII) oxidations of sodium borohydride, sodium dithionite, sodium sulfite and hydrazine sulfate in acidic aqueous solution. From the corrected chemiluminescence spectra, the wavelengths of maximum emission were 689 ± 5 nm and 734 ± 5 nm when the reactions were performed in sodium hexametaphosphate and sodium dihydrogenorthophosphate or orthophosphoric acid environments respectively. The corrected phosphorescence spectrum of manganese(II) sulfate in a solution of sodium hexametaphosphate at 77 K, exhibited two peaks with maxima at 688 nm and 730 nm. The chemical and spectroscopic evidence presented strongly supported the postulation that the emission was an example of solution phase chemically induced phosphorescence of manganese(II). Thereby confirming earlier predictions that the chemiluminescence from acidic potassium permanganate reactions originated from an excited manganese(II) species. Additionally, these findings have had direct analytical application in that manganese(IV) was evaluated as a new reagent for chemiluminescence detection. The oxidations of twenty five organic and inorganic species, with solublised manganese(IV), were found to elicit analytically useful chemiluminescence with detection limits (3 x S/N) for Mn(II), Fe(II), morphine and codeine of 5 x 10-8 M, 2.5 x 10-7 M, 7.5 x 10-8 M and 5 x 10-8M, respectively. The corrected emission spectra from four different analytes gave wavelengths of maximum emission in the range from 733 nm up to 740 nm indicating that these chemiluminescence reactions also shared a common emitting species, excited manganese(II). Whilst several analytical problems were addressed in this thesis and answers to certain questions regarding the fundamentals of acidic potassium permanganate chemiluminescence were proposed, there are several areas that would benefit from further research. These are outlined in the final chapter of this thesis.

Exercise dependence and elite Australian athletes

This thesis provides an examination of exercise dependence (EXD) among elite Australian athletes. The research identifies the main symptoms of EXD among elite athletes as excessive training, withdrawal, and continuance behaviours. EXD was found to be associated with irrational beliefs relating to training, low self esteem, and limited social support. The portfolio presents four case studies illustrating the use of solution focused brief counselling with athletes and drawing attention to the utility of a solution focused approach as an effective tool in sport psychology consultancy.

Synthesis of a novel pyrrole oxazole analogue of the insecticide pirate

The pyrrole oxazole 4 is a novel analogue of the broad-spectrum insecticide and miticide pirate 2. The expedient synthesis of pyrrole oxazole 4 in six steps from pyrrole is reported using a synthetic route that could have potential for the solution-phase combinatorial synthesis of analogues. Preliminary biological evaluation of the protected pyrrole oxazole 4 (LD₅₀ 1.13 μg mL^–1) and the deprotected pyrrole oxazole 5 (LD₅₀ 1.06 μg mL^–1) for potential cytotoxicity was carried out.

The facet selectivity of inorganic ions on silver nanocrystals in etching reactions

The facet selectivity of the halide ions and chlorauric acid for several shaped silver nanocrystals is presented in this paper. Two inorganic ions show different representations when they are used for etching silver nanocrystals in the self-sacrificial template reaction. The morphological changes of the silver nanocrystals indicate that the halide ions prefer to etch the (110) facets of silver nanocrystals, while in the chlorauric acid etching reaction, gold first modifies the (110) facets and then lets chlorauric acid etch the (111) facets instead. The selective facet etching on individual nanoparticles in the solution phase has crucial significance in the control-synthesis of nanocrystals and the facet asymmetric reaction.

One-dimensional polyelectrolyte/polymeric semiconductor core/shell structure : sulfonated poly(arylene ether ketone)/polyaniline nanofibers for organic field-effect transistors

A polyelectrolyte/polymeric semiconductor core/shell structure is developed for organic field-effect transistors (OFETs) based on sulfonated poly(arylene ether ketone)/polyaniline core/shell nanofibers via electrospinning and solution-phase selective polymerization. The polyelectrolyte does not work as a gate dielectric, but can provide an internal modulation from the nanointerface of the 1D core/shell nanostructure. The transistor devices display very high mobilities.

Sulfonated poly(ether ether ketone)/polypyrrole core–shell nanofibers : a novel polymeric adsorbent/conducting polymer nanostructures for ultrasensitive gas sensors

Conducting polymers-based gas sensors have attracted increasing research attention these years. The introduction of inorganic sensitizers (noble metals or inorganic semiconductors) within the conducting polymers-based gas sensors has been regarded as the generally effective route for further enhanced sensors. Here we demonstrate a novel route for highly-efficient conducting polymers-based gas sensors by introduction of polymeric sensitizers (polymeric adsorbent) within the conducting polymeric nanostructures to form onedimensional polymeric adsorbent/conducting polymer core−shell nanocomposites, via electrospinning and solution-phase polymerization. The adsorption effect of the SPEEK toward NH3 can facilitate the mass diffusion of NH3 through the PPy layers, resulting in the enhanced sensing signals. On the basis of the SPEEK/PPy nanofibers, the sensors exhibit large gas responses, even when exposed to very low concentration of NH3 (20 ppb) at room temperature.

Scalable Solid-Template Reduction for Designed Reduced Graphene Oxide Architectures

Herein, we report a solid-state reduction process (in contrast to solution-based approach) by using an environmentally friendly reductant, such as vitamin C (denoted VC), to be directly employed to solid-state graphene oxide (GO) templates to give the highly active rGO architecture with a sheet resistance of as low as 10 Ω sq–1. In addition, predesigned rGO patterns/tracks with tunable resistivity can be directly “written” on a preprepared solid GO film via the inkjet-printing technique using VC/H2O as the printing-ink. This advanced reduction process allows foreign active materials to be preincorporated into the GO matrix to form quality active composite architectures.

A review of the game-centred approaches to teaching and coaching literature since 2006

Background: In 2006, Oslin and Mitchell published a review of the game-centred approaches (GCAs) to teaching and coaching literature highlighting a number of core concepts thought to provide justification for the use of GCAs including (a) its potential to enhance participant motivation, (b) potential for tactical transfer, and (c) development of decision-making skills and effective decision-makers. Oslin and Mitchell also suggested recommendations for future GCA research.Purpose: The purpose of this paper was threefold: (a) to present a review of Anglophone research into GCAs building on the previous review of Oslin and Mitchell published in 2006; (b) to identify new trends in research since 2006; and (c) to investigate the extent to which the initial suggestions and future research directions suggested by Oslin and Mitchell have been addressed.Data collection: GCA literature since 2006 was searched systematically using a three-phase approach. Phase 1 included initial searches of the EBSCO database using terms associated with GCAs and their acronyms (e.g. TGfU (teaching games for understanding), GS (Game Sense), etc.). Phase 2 expanded the search adopting more generic terms from keywords located in the recent literature (e.g. teaching games, tactical development, game performance, etc.). Multiple searches through the EBSCO database were conducted, whereby key terms were cross-referenced until a saturation point was reached. Phase 3 involved removing those publications that were not empirical, peer reviewed, intervention studies or published in English.Findings: Forty-four studies on GCA implementation were identified and the methodological and substantive nature of these studies was examined. The review noted two positive trends: (a) the expansion of research which included the growth of research on GCAs in Europe and Southeast Asia and (b) an increased amount of research in the affective domain. The review found, however, that a number of key challenges remain within GCA research, which include (a) the need for improved articulation of GCA verification procedures; (b) further assessment of tactical awareness development; (c) extended inquiry about GCAs in coaching contexts; (d) more research into ‘newer’ GCAs (i.e. PP (play practice), IGCM (invasion game competence model) and TDLM (tactical decision learning model)); (e) use of longitudinal research designs; (f) inadequate length of GCA induction and training for teachers and coaches, and (g) examination of GCAs in terms of fitness and special populations.Conclusions: GCA pedagogies are of significant importance as they have the potential to promote change within current adult-centric cultures of youth sport and encourage engagement in physical activity over the life course. To meet these needs, it is recommended that GCA research undergo continued expansion with the use of research designs and data collection techniques that aid the examination of different philosophical understandings of GCAs (e.g. ethnographic, phenomenological and psycho-phenomenological). These are paramount to the exploration of ‘who the individual is’ and ‘how the learner is motivated to continue to participate’ and further permit the in-depth, contextual and ecological analysis of GCA interventions that Oslin and Mitchell recommended in their previous review.