Thermophoretic control of building units in the plasma-assisted deposition of nanostructured carbon films

The role of the plasma-grown nanoparticles in the plasma-enhanced chemical vapor deposition (PECVD) of the nanostructured carbon-based films was investigated. The samples were grown in the low-pressure rf plasmas of CH 4+H2+Ar gas mixtures. The enhanced deposition of the building units from the gas phase was found to support the formation of polymorphous nanostructured carbon films. The results reveal the crucial role played by the thermophoretic force in controlling the deposition of the plasma-grown fine particles.

The association between social support and levels of psychological distress in pregnant women in Australia

The purpose of this study was to explore associations between forms of social support and levels of psychological distress during pregnancy. Methods: A cross-sectional analysis of 2,743 pregnant women from south-east Queensland, Australia, was conducted utilising data collected between 2007-2011 as part of the Environments for Healthy Living (EFHL) project, Griffith University. Psychological distress was measured using the Kessler 6; social support was measured using the following four factors: living with a partner, living with parents or in-laws, self-perceived social network, and area satisfaction. Data were analysed using an ordered logistic regression model controlling for a range of socio-demographic factors. Results: There was an inverse association between self-perceived strength of social networks and levels of psychological distress (OR = 0.77; 95%CI: 0.70, 0.85) and between area satisfaction and levels of psychological distress (OR = 0.77; 95%CI: 0.69, 0.87). There was a direct association between living with parents or in-laws and levels of psychological distress (OR = 1.50; 95%CI: 1.16, 1.96). There was no statistically significant association between living with a partner and the level of psychological distress of the pregnant woman after accounting for household income. Conclusion: Living with parents or in-laws is a strong marker for psychological distress. Strategies aiming to build social support networks for women during pregnancy have the potential to provide a significant benefit. Policies promoting stable family relationships and networks through community development could also be effective in promoting the welfare of pregnant women.

Discharge parameters and dominant electron conductivity mechanism in a low-pressure planar magnetron discharge

Parameters of a discharge sustained in a planar magnetron configuration with crossed electric and magnetic fields are studied experimentally and numerically. By comparing the data obtained in the experiment with the results of calculations made using the proposed theoretical model, conclusion was made about the leading role of the turbulence-driven Bohm electron conductivity in the low-pressure operation mode (up to 1 Pa) of the discharge in crossed electric and magnetic fields. A strong dependence of the width of the cathode sputter trench, associated with the ionization region of the magnetron discharge, on the discharge parameters was observed in the experiments. The experimental data were used as input parameters in the discharge model that describes the motion of secondary electrons across the magnetic field in the ionization region and takes into account the classical, near-wall, and Bohm mechanisms of electron conductivity.

Effect of ambipolar fluxes on nanoparticle charging in low-pressure glow discharges

The effect of ambipolar fluxes on nanoparticle charging in a typical low-pressure parallel-plate glow discharge is considered. It is shown that the equilibrium values of the nanoparticle charge in the plasma bulk and near-electrode areas are strongly affected by the ratio S ath i of the ambipolar flux and the ion thermal velocities. Under typical experimental conditions the above ratio is neither S ath i≪ 1 nor S ath i≫1, which often renders the commonly used approximations of the purely thermal or "ion wind" ion charging currents inaccurate. By using the general approximation for the ambipolar drift-affected ion flux on the nanoparticle surface, it appears possible to obtain more accurate values of the nanoparticle charge that usually deviate within 10-25 % from the values obtained without a proper accounting for the ambipolar ion fluxes. The implications of the results obtained for glow discharge modeling and nanoparticle manipulation in low-pressure plasmas are discussed.

Low-pressure diffusion equilibrium of electronegative complex plasmas

A model for electronegative plasmas containing charged dust or colloidal grains was used. Numerical solutions based on the model demonstrate how a low-pressure diffusion equilibrium of the complex electronegative plasma system is dynamically sustained through plasma particle sources.

Coming into an inheritance : family support and Chinese heritage language learning

The critical role that family plays in Chinese Heritage Language learning has gained increasing attention from psychological, political and sociological scholarship. Guided by Bourdieu’s notion of ‘habitus’, our mixed methods sociological study firstly addresses the need for quantitative evidence on the relationship between family support and Chinese Heritage Language proficiency through a survey of 230 young Chinese Australians; and then explores the dynamics of family support of Chinese Heritage Language learning through multiple interviews with five participants. The interview data demonstrate ongoing intergenerational reproduction of Chinese Heritage Language through various forms of family inculcation. Learners’ transition from resistance to commitment is a focus of the analysis. Extant research struggles to theorise the reasons behind this transition. We offer a Bourdieusian explanation that construes the transition as ‘habitus realisation’. Our study has implications for Chinese Heritage Language researchers, Chinese immigrant parents and Chinese teachers.

Electron energy distribution function in low-pressure complex plasmas

The effect of density and size of dust grains on the electron energy distribution function (EEDF) in low-temperature complex plasmas is studied. It is found that the EEDF depends strongly on the dust density and size. The behavior of the electron temperature can differ significantly from that of a pristine plasma. For low-pressure argon glow discharge, the Druyvesteyn-like EEDF often found in pristine plasmas can become nearly Maxwellian if the dust density and/or sizes are large. One can thus control the plasma parameters by the dust grains.

Organizational support and enterprise web 2.0 adoption : a qualitative study

The emerging growth of Web 2.0 has been observed by users in the workplace, and has therefore encouraged organisations to introduce Web 2.0 technologies in their businesses. Although its adoption is beneficial, it could meets with employees resistance due to some organisational factors. The successful implementation of Enterprise Web 2.0 is based on employee adoption of such social technology. Using a qualitative study, this research explores how organizational support can influence employees’ adoption of Enterprise Web 2.0. The findings show that organisational support encourages and facilitates a smooth adoption. Such support can be provided by management and colleagues in several forms: developing a Web 2.0 strategy, providing required resources for such training, recognising and encouraging adopters, and involving managers in the adoption.

Atmospheric-pressure plasma jets : effect of gas flow, active species, and snake-like bullet propagation

Cold atmospheric-pressure plasma jets have recently attracted enormous interest owing to numerous applications in plasma biology, health care, medicine, and nanotechnology. A dedicated study of the interaction between the upstream and downstream plasma plumes revealed that the active species (electrons, ions, excited OH, metastable Ar, and nitrogen-related species) generated by the upstream plasma plume enhance the propagation of the downstream plasma plume. At gas flows exceeding 2 l/min, the downstream plasma plume is longer than the upstream plasma plume. Detailed plasma diagnostics and discharge species analysis suggest that this effect is due to the electrons and ions that are generated by the upstream plasma and flow into the downstream plume. This in turn leads to the relatively higher electron density in the downstream plasma. Moreover, high-speed photography reveals a highly unusual behavior of the plasma bullets, which propagate in snake-like motions, very differently from the previous reports. This behavior is related to the hydrodynamic instability of the gas flow, which results in non-uniform distributions of long-lifetime active species in the discharge tube and of surface charges on the inner surface of the tube.

Computational fluid dynamics simulation and turbomachinery code validation of a high pressure ratio radial-inflow turbine

The present study explores reproducing the closest geometry of a high pressure ratio single stage radial-inflow turbine applied in the Sundstrans Power Systems T-100 Multipurpose Small Power Unit. The commercial software ANSYS-Vista RTD along with a built in module, BladeGen, is used to conduct a meanline design and create 3D geometry of one flow passage. Carefully examining the proposed design against the geometrical and experimental data, ANSYS-TurboGrid is applied to generate computational mesh. CFD simulations are performed with ANSYS-CFX in which three-dimensional Reynolds-Averaged Navier-Stokes equations are solved subject to appropriate boundary conditions. Results are compared with numerical and experimental data published in the literature in order to generate the exact geometry of the existing turbine and validate the numerical results against the experimental ones.

SWCNT networks on nanoporous silica catalyst support : morphological and connectivity control for nanoelectronic, gas-sensing, and biosensing devices

Effective control of morphology and electrical connectivity of networks of single-walled carbon nanotubes (SWCNTs) by using rough, nanoporous silica supports of Fe catalyst nanoparticles in catalytic chemical vapor deposition is demonstrated experimentally. The very high quality of the nanotubes is evidenced by the G-to-D Raman peak ratios (>50) within the range of the highest known ratios. Transitions from separated nanotubes on smooth SiO2 surface to densely interconnected networks on the nanoporous SiO2 are accompanied by an almost two-order of magnitude increase of the nanotube density. These transitions herald the hardly detectable onset of the nanoscale connectivity and are confirmed by the microanalysis and electrical measurements. The achieved effective nanotube interconnection leads to the dramatic, almost three-orders of magnitude decrease of the SWCNT network resistivity compared to networks of similar density produced by wet chemistry-based assembly of preformed nanotubes. The growth model, supported by multiscale, multiphase modeling of SWCNT nucleation reveals multiple constructive roles of the porous catalyst support in facilitating the catalyst saturation and SWCNT nucleation, consistent with the observed higher density of longer nanotubes. The associated mechanisms are related to the unique surface conditions (roughness, wettability, and reduced catalyst coalescence) on the porous SiO2 and the increased carbon supply through the supporting porous structure. This approach is promising for the direct integration of SWCNT networks into Si-based nanodevice platforms and multiple applications ranging from nanoelectronics and energy conversion to bio- and environmental sensing.

High-yield atmospheric-pressure CVD of highly-uniform carbon nanocoils using Co–P catalyst nanoparticles prepared by electroless plating

A simple, fast and low-cost atmospheric-pressure chemical vapor deposition technique is developed to synthesize high-yield carbon nanocoils (CNCs) using amorphous Co–P alloy as catalyst and thiophene as nucleation agent. The uniform catalyst pattern with the mean particle size of 350 nm was synthesized using a simple electroless plating process. This uniformity of the Co–P nanoparticles results in a high yield, very uniform size/shape distribution and regular structure of CNCs at the optimum growth temperature of 800 ◦C. The yield of CNCs reaches ∼76%; 70% of the CNCs have fiber diameters approximately 250 nm. The CNC coil diameters and lengths are 450–550nm and 0.5–2mm, respectively. The CNC nucleation and growth mechanism are also discussed.

A digital airport experience : design-led innovation in support of airport strategy

The digital era is proving to be one of disruption, where new technologies matched with innovative business models can be harnessed to attack even the most established of companies. For businesses with the relative certainty of captive customer bases, such as airports, the ability to digitally diversify offers the opportunity to venture into new modes of operation. For an airport, this opportunity can also be leveraged to sustain superior customer support regardless of a customer’s location in the world. This research paper presents a case study of the development of an Australian Airport Corporation’s mobile application as part of a greater digital strategy initiative using a design-led approach to innovate. An action research method provides the platform for an intensive embedded practice and study of design-led innovation within the major Australian Airport Corporation. The findings reveal design-led innovation to be a crucial in-house idea generation and concept development capability enabling the bridging of distinct corporate domains associated with commercialisation, operations and customer experience. A Digital Innovation Checklist is presented as an output of this research which structures an organizational approach toward digital channel innovation. The practitioner’s checklist is designed to aid in the future development of digital channels within the broader spectrum of strategy by addressing business assumptions.

The knowledge of doing: Exploring the knowledge of support to older people with an intellectual disability

This ethnography presents a contextualised understanding of frontline knowledge used in the support to people ageing with an intellectual disability who live in accommodation and support services in south-east Queensland. The study identified that disability support workers accessed a range of knowledges which they synthesised into a dynamic and responsive locale knowledge, and subsequently translated into everyday acts of support within contexts of multi-faceted complexity. Findings from the study have numerous implications for the knowledge development activities of formal service and educational systems within Australia's newly implemented National Disability Insurance Scheme.

E-mail in the workplace : the role of stress appraisals and normative response pressure in the relationship between email stressors and employee strain

In many organizations, e-mail is an effective and dominant workplace application tool; however, research identifying its role as a potential workplace stressor remains limited. Utilizing the Transactional Model of Stress (Lazarus & Folkman, 1984), 215 full-time administrative and academic staff at a university were surveyed about workplace e-mail. The aim was to study the effects of potential e-mail stressors on emotional exhaustion as mediated and moderated by person and situation variables. Results indicated that 2 distinct e-mail stressors—high quantity and poor quality (in terms of high emotionality and ambiguity) of workplace e-mail—were associated both with stress appraisals (e-mail overload and e-mail uncertainty) and with emotional exhaustion. Furthermore, the effects of the 2 e-mail stressors on emotional exhaustion were mediated by appraised e-mail overload. Perceived normative response pressure—a relevant aspect of the specific work environment—added to the explanation of emotional exhaustion and accentuated the positive effect of e-mail ambiguity on emotional exhaustion, although effects involving normative response pressure were not explained by the stress appraisals.