A report on the sisal language project

Sisal (Streams and Iterations in Single Assignment Language) is a general-purpose applicative language intended for use on both conventional and novel multiprocessor systems. In this report we discuss the project's objectives, philosophy, and accomplishments and state our future plans. Four significant results of the Sisal project are compilation techniques for high-performance parallel applicative computation, a microtasking environment that supports dataflow on conventional shared-memory architectures, execution times comparable to those of Fortran, and cost-effective speedup on shared-memory multiprocessors.     

Computational fluid dynamics and electrostatic modeling of polymerization fluidized-bed reactors

Electrostatics plays an important role in gas-solid polymerization fluidized-bed reactors. Agglomeration of polymer particles can occur due to either electrostatic and/or thermal effects, and can lead to reactor operability problems if not properly mitigated. In this work a first-principles electrostatic model is developed and coupled with a multi-fluid computational fluid dynamic (CFD) model to understand the effect of electrostatics on the bulk polymer, polymer fines, and catalyst particles. The multi-phase CFD model for gas-solid flow is based on the kinetic theory of granular flows and the frictional theory. The electrostatic model is developed based on a fixed, size-dependent charge for each type of particle (catalyst, polymer fines and polymer). The combined CFD model is first verified using simple test cases and then applied to a pilot-plant-scale polymerization fluidized-bed reactor. The multi-phase CFD model is applied to reproduce qualitative trends in particle segregation and entrainment due to electrostatic charges observed in experiments.     

Preparation of activated graphene and effect of activation parameters on electrochemical capacitance

Activation parameters such as temperature and the amount of potassium hydroxide (KOH) were varied during the synthesis of activated microwave-exfoliated graphite oxide (a-MEGO) and the effects of these parameters on the specific surface area of a-MEGO and electrochemical capacitance of a-MEGO electrodes were investigated. At 800 °C and a KOH/MEGO mass ratio of 6.5, a maximum specific surface area of 3100 m²/g was obtained and a high specific capacitance of 172 F/g (at 1 A/g constant current and 3.5 V maximal voltage) was measured in a two-electrode cell with a-MEGO electrodes in an organic electrolyte.     

Enhancement of β phase crystals formation with the use of nanofillers in PVDF films and fibres

Nanoclay and carbon nanotubes (CNT) have been in focus recently as means of enhancing β phase crystals formation in poly(vinylidene fluoride)(PVDF). Dominantly, the so-far work has been carried out on films/thin sheets filled with nanoclay. It has been found, mainly from combined XRD and DSC data, that nanoclay influences the PVDF structure, and particularly the β phase crystals formation is enhanced. Results published by various groups are in fairly good agreement. There are no results for nanoclay filled melt-spun PVDF fibres.The influence of CNT on PVDF structure has been less studied. XRD data indicating an enhancing role of multi-wall carbon nanotubes (MWNT) on β phase crystals formation in solution compounded PVDF films are available. Published results for MWNT/PVDF films are not in good agreement. The only study into single-wall carbon nanotube (SWNT)/PVDF has been made on electrospun nanofibres.We explore above findings towards melt-spun nanofilled PVDF fibres. We present new results obtained by us for melt-spun PVDF fibres containing non-functionalized and amino-functionalized double-wall carbon nanotubes (DWNT). The key finding is that amino-DWNT can influence the β to α polymorphic balance.     

Investigation of reactions between vanadium oxide and plasma-sprayed yttria-stabilized zirconia coatings

The phase evolution occurring during the reaction between corrosive V₂O₅ (T_m = 690 °C) and a plasma-sprayed 7 wt.% Y₂O₃–ZrO₂ (YSZ) coating from 700 to 900 °C has been investigated in situ by X-ray diffraction. The temperature and time of interaction between the V₂O₅ and YSZ coating determines the phases observed. Between 700 and 750 °C, reaction products of ZrV₂O₇ and YVO₄ were observed within minutes of reaching the test temperature. m-ZrO₂ was observed after 220 and 60 min at 700 and 750 °C, respectively. The simultaneous formation of both ZrV₂O₇ and YVO₄ at the beginning of the reaction along with the delay of the m-ZrO₂ formation suggests similar reactivity between both Zr and Y with V₂O₅. The weight percent of the ZrV₂O₇ phase began to diminish after 150 and 60 min at 700 and 750 °C, respectively. For reaction temperatures of 800 and 900 °C, there is a rapid decrease in the amount of t′-ZrO₂ and a rapid increase in the amount of m-ZrO₂ with reaction time. YVO₄ was also observed at these reaction temperatures. SEM and TEM microstructural observations confirmed the phases detected from the in situ XRD experiments. Reactions between YSZ and V₂O₅ suggest that the formation of a liquid phase due to the high solubility of both zirconia and yttria in vanadia is the dominate mechanism that damages the coating. The thermal conductivity of a plasma-sprayed YSZ coating reacted with up to 1 wt.% V₂O₅ did not significantly change due to the small volume affected.     

Critical pathways to enhanced innovation diffusion and business performance in Australian design firms

This paper presents a study that extends on previous empirical research, which examined the role of enabling ‘climate for innovation’ constructs in determining the level of innovation diffusion outcomes, and subsequent business performance in architectural and engineering design (AED) firms. Whilst this previous study elucidated the relationships between broad theoretical constructs, the present study was focused on targeting the significant enabling factor interrelationships with the core outcomes that result from the innovation diffusion process. To achieve this objective, a sequential mixed-method research design combining quantitative and qualitative analysis techniques was employed. The quantitative techniques included a correlation analysis to identify the strong factor relationships, followed by Structural Equation Modelling (SEM) to determine the critical pathways for enhancing innovation diffusion and ultimately heightened levels of client satisfaction. Following path model extraction, qualitative interviews with five Australian AED firms were conducted. The interview findings confirmed the uncovered significant pathways, and provided in-depth insights into how the improvement of critical enabling factors could leverage improved innovation diffusion outcomes and business performance.